WorldWideScience

Sample records for altitude research aircraft

  1. NASA/USRA high altitude research aircraft. Gryphon: Soar like an eagle with the roar of a lion

    Science.gov (United States)

    Rivera, Jose; Nunes, Anne; Mcray, Mike; Wong, Walter; Ong, Audrey; Coble, Scott

    1991-01-01

    At the equator, the ozone layer ranges from 65,000 to 130,000+ feet. This is beyond the capabilities of the ER-2, which is NASA's current high altitude reconnaissance aircraft. The Universities Space Research Association, in cooperation with NASA, is sponsoring an undergraduate program which is geared to designing an aircraft that can study the ozoned layer at the equator. This aircraft must be able to satisfy four mission profiles. Mission one is a polar mission which ranges from Chile to the South Pole and back to Chile, a total range of 6000 n. mi. at 100,000 feet with a 2500 lb. payload. The second mission is also a polar mission with a decreased altitude of 70,000 feet and an increased payload of 4000 lb. For the third mission, the aircraft will take-off at NASA Ames, cruise at 100,000 feet carrying a 2500 lb. payload, and land in Puerto Montt, Chile. The final mission requires the aircraft to take-off at NASA Ames, cruise at 100,000 feet with a 1000 lb. payload, make an excursion to 120,000 feet, and land at Howard AFB, Panama. All three missions require that a subsonic Mach number be maintained due to constraints imposed by the air sampling equipment. The aircraft need not be manned for all four missions. Three aircraft configurations were determined to be the most suitable for meeting the above requirements. The performance of each configuration is analyzed to investigate the feasibility of the project requirements. In the event that a requirement can not be obtained within the given constraints, recommendations for proposal modifications are given.

  2. High altitude aircraft flight tests

    Science.gov (United States)

    Helmken, Henry; Emmons, Peter; Homeyer, David

    1996-03-01

    In order to make low earth orbit L-band propagation measurements and test new voice communication concepts, a payload was proposed and accepted for flight aboard the COMET (now METEOR) spacecraft. This Low Earth Orbiting EXperiment payload (LEOEX) was designed and developed by Motorola Inc. and sponsored by the Space Communications Technology Center (SCTC), a NASA Center for the Commercial Development of Space (CCDS) located at Florida Atlantic University. In order to verify the LEOEX payload for satellite operation and obtain some preliminary propagation data, a series of 9 high altitude aircraft (SR-71 and ER-2) flight tests were conducted. These flights took place during a period of 7 months, from October 1993 to April 1994. This paper will summarize the operation of the LEOEX payload and the particular configuration used for these flights. The series of flyby tests were very successful and demonstrated how bi-directional, Time Division Multiple Access (TDMA) voice communication will work in space-to-ground L-band channels. The flight tests also acquired propagation data which will be representative of L-band Low Earth Orbiting (LEO) communication systems. In addition to verifying the LEOEX system operation, it also uncovered and ultimately aided the resolution of several key technical issues associated with the payload.

  3. Energy management strategy for solar-powered high-altitude long-endurance aircraft

    International Nuclear Information System (INIS)

    Highlights: ► A new Energy Management Strategy (EMS) for high-altitude solar-powered aircraft is purposed. ► The simulations show that the aircraft can always keep the altitude above 16 km with the proposed EMS. ► The proposed EMS is capable to alleviate the power consumed for aircraft during night. ► The main technologies to improve the flight performance of aircraft are analyzed. - Abstract: Development of solar-powered High-Altitude Long-Endurance (HALE) aircraft has a great impact on both military and civil aviation industries since its features in high-altitude and energy source can be considered inexhaustible. Owing to the development constraints of rechargeable batteries, the solar-powered HALE aircraft must take amount of rechargeable batteries to fulfill the energy requirement in night, which greatly limits the operation altitude of aircraft. In order to solve this problem, a new Energy Management Strategy (EMS) is proposed based on the idea that the solar energy can be partly stored in gravitational potential in daytime. The flight path of HALE aircraft is divided into three stages. During the stage 1, the solar energy is stored in both lithium–sulfur battery and gravitational potential. The gravitational potential is released in stage 2 by gravitational gliding and the required power in stage 3 is supplied by lithium–sulfur battery. Correspondingly, the EMS is designed for each stage. The simulation results show that the aircraft can always keep the altitude above 16 km with the proposed EMS, and the power consumed during night can be also alleviated. Comparing with the current EMS, about 23.5% energy is remained in batteries with the proposed EMS during one day–night cycle. The sensitivities of the improvement of crucial technologies to the performance of aircraft are also analyzed. The results show that the enhancement of control and structural system, lithium–sulfur battery, and solar cell are ranked in descending order for the

  4. Analysis of the Hybrid Power System for High-Altitude Unmanned Aircraft

    Directory of Open Access Journals (Sweden)

    Kangwen Sun

    2015-01-01

    Full Text Available The application of single solar array on high-altitude unmanned aircraft will waste energy because of its low conversion efficiency. Furthermore, since its energy utilization is limited, the surface temperature of solar array will rise to 70°C due to the waste solar energy, thus reducing the electrical performance of the solar array. In order to reuse the energy converted into heat by solar array, a hybrid power system is presented in this paper. In the hybrid power system, a new electricity-generating method is adopted to spread the photovoltaic cell on the wing surface and arrange photothermal power in the wing box section. Because the temperature on the back of photovoltaic cell is high, it can be used as the high-temperature heat source. The lower wing surface can be a low-temperature cold source. A high-altitude unmanned aircraft was used to analyze the performances of pure solar-powered aircraft and hybrid powered aircraft. The analysis result showed that the hybrid system could reduce the area of wing by 19% and that high-altitude unmanned aircraft with a 35 m or less wingspan could raise the utilization rate of solar energy per unit area after adopting the hybrid power system.

  5. Effect of power system technology and mission requirements on high altitude long endurance aircraft

    Science.gov (United States)

    Colozza, Anthony J.

    1994-01-01

    An analysis was performed to determine how various power system components and mission requirements affect the sizing of a solar powered long endurance aircraft. The aircraft power system consists of photovoltaic cells and a regenerative fuel cell. Various characteristics of these components, such as PV cell type, PV cell mass, PV cell efficiency, fuel cell efficiency, and fuel cell specific mass, were varied to determine what effect they had on the aircraft sizing for a given mission. Mission parameters, such as time of year, flight altitude, flight latitude, and payload mass and power, were also altered to determine how mission constraints affect the aircraft sizing. An aircraft analysis method which determines the aircraft configuration, aspect ratio, wing area, and total mass, for maximum endurance or minimum required power based on the stated power system and mission parameters is presented. The results indicate that, for the power system, the greatest benefit can be gained by increasing the fuel cell specific energy. Mission requirements also substantially affect the aircraft size. By limiting the time of year the aircraft is required to fly at high northern or southern latitudes, a significant reduction in aircraft size or increase in payload capacity can be achieved.

  6. Cosmic-radiation dosimetry using electronic personal dosemeter (EPD) at commercial aircraft altitude

    International Nuclear Information System (INIS)

    Electronic Personal Dosemeter (EPD) was examined for effectiveness in cosmic radiation dosimetry at aircraft altitude through the measurements in a Japan-US round trip. The EPD value (Hepd) of individual dose equivalent, penetrating, Hp(10), was considered to be almost equal the deep absorbed dose attributed to electrons at the aircraft altitude. By assuming the fractions and the effective quality factors for other components (muons, protons, and neutrons) based on model-calculation data, an empirical equation to estimate a conservative deep dose-equivalent at 5 cm-tissue depth, H(50), was given as H(50)=3.1 x Hepd. Estimated H(50) values in the international flights were 4.9 μSv h-1 from Tokyo to New York and 3.6 μSv h-1 from Los Angeles to Tokyo. These values agreed well with the predicted values presented by NCRP. (author)

  7. The equivalence of gravitational potential and rechargeable battery for high-altitude long-endurance solar-powered aircraft on energy storage

    International Nuclear Information System (INIS)

    Highlights: • The scope of this paper is to apply solar energy to achieve the high-altitude long-endurance flight. • The equivalence of gravitational potential and rechargeable battery is discussed. • Four kinds of factors have been discussed to compare the two method of energy storage. • This work can provide some governing principles for the application of solar-powered aircraft. - Abstract: Applying solar energy is one of the most promising methods to achieve the aim of High-altitude Long-endurance (HALE) flight, and solar-powered aircraft is usually taken by the research groups to develop HALE aircraft. However, the crucial factor which constrains the solar-powered aircraft to achieve the aim of HALE is the problem how to fulfill the power requirement under weight constraint of rechargeable batteries. Motivated by the birds store energy from thermal by gaining height, the method of energy stored by gravitational potential for solar-powered aircraft have attracted great attentions in recent years. In order to make the method of energy stored in gravitational potential more practical in solar-powered aircraft, the equivalence of gravitational potential and rechargeable battery for aircraft on energy storage has been analyzed, and four kinds of factors are discussed in this paper: the duration of solar irradiation, the charging rate, the energy density of rechargeable battery and the initial altitude of aircraft. This work can provide some governing principles for the solar-powered aircraft to achieve the unlimited endurance flight, and the endurance performance of solar-powered aircraft may be greatly improved by the application of energy storage using gravitational potential

  8. Experimental characterization of the COndensation PArticle counting System for high altitude aircraft-borne application

    Directory of Open Access Journals (Sweden)

    R. Weigel

    2008-11-01

    Full Text Available This study aims at a detailed characterization of an ultra-fine aerosol particle counting system for operation on board the Russian high altitude research aircraft M-55 "Geophysica" (maximum ceiling of 21 km. The COndensation PArticle counting Systems (COPAS consists of an aerosol inlet and two dual-channel continuous flow Condensation Particle Counters (CPCs.

    The aerosol inlet, adapted for COPAS measurements on board the M-55 "Geophysica", is described concerning aspiration, transmission, and transport losses. The counting efficiencies of the CPCs using the chlorofluorocarbon FC-43 as the working fluid are studied experimentally at two pressure conditions, 300 hPa and 70 hPa. Three COPAS channels are operated with different temperature differences between the saturator and the condenser block yielding smallest detectable particle sizes (dp50 – as 50% detection "cut off" diameters of 6 nm, 11 nm, and 15 nm, respectively, at ambient pressure of 70 hPa. The fourth COPAS channel is operated with an aerosol heating line (250°C for a determination of the non-volatile number of particles. The heating line is experimentally proven to volatilize pure H2SO4-H2O particles for a particle diameter (dp range of 11 nm<dp<200 nm.

    Additionally this study includes investigation to exclude auto-nucleation of the working fluid inside the CPCs. An instrumental inter-comparison (cross-correlation has been performed for several measurement flights and mission flights in the Arctic and the Tropics are discussed. Finally, COPAS measurements are used for an aircraft plume crossing analysis.

  9. Experimental characterization of the COndensation PArticle counting System for high altitude aircraft-borne application

    Directory of Open Access Journals (Sweden)

    S. Borrmann

    2009-06-01

    Full Text Available A characterization of the ultra-fine aerosol particle counter COPAS (COndensation PArticle counting System for operation on board the Russian high altitude research aircraft M-55 Geophysika is presented. The COPAS instrument consists of an aerosol inlet and two dual-channel continuous flow Condensation Particle Counters (CPCs operated with the chlorofluorocarbon FC-43. It operates at pressures between 400 and 50 hPa for aerosol detection in the particle diameter (dp range from 6 nm up to 1 μm. The aerosol inlet, designed for the M-55, is characterized with respect to aspiration, transmission, and transport losses. The experimental characterization of counting efficiencies of three CPCs yields dp50 (50% detection particle diameter of 6 nm, 11 nm, and 15 nm at temperature differences (ΔT between saturator and condenser of 17°C, 30°C, and 33°C, respectively. Non-volatile particles are quantified with a fourth CPC, with dp50=11 nm. It includes an aerosol heating line (250°C to evaporate H2SO4-H2O particles of 11 nm<dp<200 nm at pressures between 70 and 300 hPa. An instrumental in-flight inter-comparison of the different COPAS CPCs yields correlation coefficients of 0.996 and 0.985. The particle emission index for the M-55 in the range of 1.4–8.4×1016 kg−1 fuel burned has been estimated based on measurements of the Geophysika's own exhaust.

  10. Hydrogen Fuel System Design Trades for High-Altitude Long-Endurance Remotely- Operated Aircraft

    Science.gov (United States)

    Millis, Marc G.; Tornabene, Robert T.; Jurns, John M.; Guynn, Mark D.; Tomsik, Thomas M.; VanOverbeke, Thomas J.

    2009-01-01

    Preliminary design trades are presented for liquid hydrogen fuel systems for remotely-operated, high-altitude aircraft that accommodate three different propulsion options: internal combustion engines, and electric motors powered by either polymer electrolyte membrane fuel cells or solid oxide fuel cells. Mission goal is sustained cruise at 60,000 ft altitude, with duration-aloft a key parameter. The subject aircraft specifies an engine power of 143 to 148 hp, gross liftoff weight of 9270 to 9450 lb, payload of 440 lb, and a hydrogen fuel capacity of 2650 to 2755 lb stored in two spherical tanks (8.5 ft inside diameter), each with a dry mass goal of 316 lb. Hydrogen schematics for all three propulsion options are provided. Each employs vacuum-jacketed tanks with multilayer insulation, augmented with a helium pressurant system, and using electric motor driven hydrogen pumps. The most significant schematic differences involve the heat exchangers and hydrogen reclamation equipment. Heat balances indicate that mission durations of 10 to 16 days appear achievable. The dry mass for the hydrogen system is estimated to be 1900 lb, including 645 lb for each tank. This tank mass is roughly twice that of the advanced tanks assumed in the initial conceptual vehicle. Control strategies are not addressed, nor are procedures for filling and draining the tanks.

  11. Calculations and observations of solar particle enhancements to the radiation environment at aircraft altitudes

    Science.gov (United States)

    Dyer, C. S.; Lei, F.; Clucas, S. N.; Smart, D. F.; Shea, M. A.

    Solar particle events can give greatly enhanced radiation at aircraft altitudes, but are both difficult to predict and to calculate retrospectively. This enhanced radiation can give significant dose to aircrew and greatly increase the rate of single event effects in avionics. Validation of calculations is required but only very few events have been measured in flight. The CREAM detector on Concorde detected the event of 29 September 1989 and also four periods of enhancement during the events of 19-24 October 1989. Instantaneous rates were enhanced by up to a factor ten compared with quiet-time cosmic rays, while flight-averages were enhanced by up to a factor six. Calculations are described for increases in radiation at aircraft altitudes using solar particle spectra in conjunction with Monte Carlo radiation transport codes. In order to obtain solar particle spectra with sufficient accuracy over the required energy range it is necessary to combine space data with measurements from a wide range of geomagnetically dispersed, ground-level neutron monitors. Such spectra have been obtained for 29 September 1989 and 24 October 1989 and these are used to calculate enhancements that are compared with the data from CREAM on Concorde. The effect of cut-off rigidity suppression by geomagnetic activity is shown to be significant. For the largest event on record on 23 February 1956, there are no space data but there are data from a number of ground-level cosmic-ray detectors. Predictions for all events show very steep dependencies on both latitude and altitude. At high latitude and altitude (17 km) calculated increases with respect to cosmic rays are a factor 70 and 500 respectively for 29 September 1989 and 23 February 1956. The levels of radiation for high latitude, subsonic routes are calculated, using London to Los Angeles as an example, and can exceed 1 mSv, which is significantly higher than for Concorde routes from Europe to New York. The sensitivity of the calculations

  12. Supercharging system behavior for high altitude operation of an aircraft 2-stroke Diesel engine

    International Nuclear Information System (INIS)

    Highlights: • Different supercharging architectures have been compared for an aircraft 2T engine. • The supercharging architectures are compared to minimize the fuel consumption. • The architecture with the highest conversion efficiency was determined. - Abstract: Different studies on both 2- and 4-stroke engines have shown how the choice of different supercharging architectures can influence engine performance. Among them, architectures coupling one turbocharger with a mechanical compressor or two turbochargers are found to be the most performing in terms of engine output power and efficiency. However, defining the best supercharging architecture for aircraft 2-stroke engines is a quite complex task because the supercharging system as well as the ambient conditions influence the engine performance/efficiency. This is due to the close interaction between supercharging, trapping, scavenging and combustion processes. The aim of the present work is the comparison between different architectures (single turbocharger, double turbocharger, single turbocharger combined with a mechanical compressor, single turbocharger with an electrically-assisted turbocharger, with intercooler or aftercooler) designed to supercharge an aircraft 2-stroke Diesel engine for general aviation and unmanned aerial vehicles characterized by a very high altitude operation and long fuel distance. A 1D model of the engine purposely designed has been used to compare the performance of the different supercharging systems in terms of power, fuel consumption, and their effect on trapping and scavenging efficiency at different altitudes. The analysis shows that the engine target power is reached by a 2 turbochargers architecture; in this way, in fact, the cylinder filling, and consequently the engine performance, are maximized. Moreover, it is shown that the performance of a 2 turbochargers architecture performance can be further improved connecting electrically and not mechanically the low

  13. Nitrogen oxides at the UTLS: Combining observations from research aircraft and in-service aircraft

    Science.gov (United States)

    Ziereis, Helmut; Stratmann, Greta; Schlager, Hans; Gottschaldt, Klaus-Dirk; Rauthe-Schöch, Armin; Zahn, Andreas; Hoor, Peter; van, Peter

    2016-04-01

    Nitrogen oxides have a decisive influence on the chemistry of the upper troposphere and lower stratosphere. They are key constituents of several reaction chains influencing the production of ozone. They also play an essential role in the cycling of hydroxyl radicals and therefore influence the lifetime of methane. Due to their short lifetime and their variety of sources there is still a high uncertainty about the abundance of nitrogen oxides in the UTLS. Dedicated aircraft campaigns aim to study specific atmospheric questions like lightning, long range transport or aircraft emissions. Usually, within a short time period comprehensive measurements are performed within a more or less restricted region. Therefore, especially trace constituents like nitrogen oxides with short lifetime and a variety of different sources are not represented adequately. On the other hand, routine measurements from in-service aircraft allow observations over longer time periods and larger regions. However, it is nearly impossible to influence the scheduling of in-service aircraft and thereby time and space of the observations. Therefore, the combination of dedicated aircraft campaigns and routine observations might supplement each other. For this study we combine nitrogen oxides data sets obtained with the IAGOS-CARIBIC (Civil Aircraft for the Regular Investigation of the Atmosphere Based on an Instrument Container) flying laboratory and with the German research aircraft HALO (High altitude and long range research aircraft). Data have been acquired within the IAGOS-CARIBIC project on a monthly base using a Lufthansa Airbus A340-600 since December 2004. About four flights are performed each month covering predominantly northern mid-latitudes. Additional flights have been conducted to destinations in South America and South Africa. Since 2012 HALO has been operational. Nitrogen oxides measurements have been performed during six missions covering mid latitudes, tropical as well as Polar

  14. HAMP - the microwave package on the upcoming High Altitude and LOng range aircraft HALO

    Science.gov (United States)

    Mech, M.; Crewell, S.; Peters, G.; Hirsch, L.

    2009-04-01

    New cloud observation techniques are needed to improve our understanding of the impact of clouds on the earth's water cycle and radiation budget, which represents still one of the largest uncertainties in global and regional climate modeling. An airborne platform for such observation techniques will be provided by the new German research aircraft HALO (High Altitude Long Range) that will be commissioned in 2009. HALO will open a new dimension for climate and atmospheric research. By HALO it will be possible to survey the atmosphere on continental scales but with much finer resolution and with more powerful instrumentation than feasible on space borne platforms. An advanced set of microwave remote cloud sensing instruments (HAMP - HALO Microwave Package) will be operated on board of HALO. It consists of a cloud radar and a suite of passive radiometers in different frequency bands. The radar MIRA-36 operates at 36.5 GHz. Although this is an unusual low frequency, it benefits from the wider range of applications due to less signal attenuation in deep clouds and rain, compared to the 94 GHz radar operated on CloudSat. The frequencies for the passive microwave radiometers were selected in allusion to the AMSU-A and -B sounder. Thereby the 150 GHz channel of AMSU-B has been replaced by frequencies in the 118 GHz oxygen band. In combination with the 60 GHz oxygen complex channels, this frequencies can be used for precipitation retrieval after Bauer and Mugnai (2003). Furthermore by including channels in the water vapor lines at 22.235 GHz and 183.31 GHz and higher microwave channels sensitive to scattering in the ice phase, various precipitation retrieval algorithms can be compared by measurements with HAMP. This presentation introduces the microwave package on HALO. It further shows the potential of the observations by presenting results of a simulation study for the selected microwave frequencies and the cloud radar. The potential of the selected frequencies for

  15. Weather Avoidance Guidelines for NASA Global Hawk High-Altitude Unmanned Aircraft Systems (UAS)

    Science.gov (United States)

    Cecil, Daniel J.; Zipser, Edward J.; Velden, Chris S.; Monette, Sarah A.; Heymsfield, Gerald M.; Braun, Scott A.; Newman, Paul A.; Black, Peter G.; Black, Michael L.; Dunion, Jason P.

    2014-01-01

    The current Global Hawk flight rules would probably not have been effective in the single event of greatest concern (the Emily encounter). The cloud top had not reached 50,000 ft until minutes before the encounter. The TOT and lightning data would not have been available until near the overflight time since this was a rapidly growing cell. This case would have required a last-minute diversion when lightning became frequent. Avoiding such a cell probably requires continual monitoring of the forward camera and storm scope, whether or not cloud tops have been exceeding specific limits. However, the current overflight rules as strictly interpreted would have prohibited significant fractions of the successful Global Hawk overpasses of Karl and Matthew that proved not to be hazardous. Many other high altitude aircraft (ER-2 and Global Hawk) flights in NASA tropical cyclone field programs have successfully overflown deep convective clouds without incident.The convective cell that caused serious concern about the safety of the ER-2 in Emily was especially strong for a tropical cyclone environment, probably as strong or stronger than any that was overflown by the ER-2 in 20 previous flights over tropical cyclones. Specifically, what made that cell a safety concern was the magnitude of the vertical velocity of the updraft, at least 20 m/s (4000 ft/minute) at the time the ER-2 overflew it. Such a strong updraft can generate strong gravity waves at and above the tropopause, posing a potential danger to aircraft far above the maximum altitude of the updraft itself or its associated cloud top. Indeed, the ER-2 was probably at least 9000 ft above that cloud top. Cloud-top height, by itself, is not an especially good indicator of the intensity of convection and the likelihood of turbulence. Nor is overflying high cloud tops (i.e. > 50,000 ft) of particular concern unless there is other evidence of very strong convective updrafts beneath those tops in the path of the aircraft

  16. Research on Emerging and Descending Aircraft Noise

    Directory of Open Access Journals (Sweden)

    Monika Bartkevičiūtė

    2013-12-01

    Full Text Available Along with an increase in the aircraft engine power and growth in air traffic, noise level at airports and their surrounding environs significantly increases. Aircraft noise is high level noise spreading within large radius and intensively irritating the human body. Air transport is one of the main sources of noise having a particularly strong negative impact on the environment. The article deals with activities and noises taking place in the largest nationwide Vilnius International Airport.The level of noise and its dispersion was evaluated conducting research on the noise generated by emerging and descending aircrafts in National Vilnius Airport. Investigation was carried out at 2 measuring points located in a residential area. There are different types of aircrafts causing different sound levels. It has been estimated the largest exceedances that occur when an aircraft is approaching. In this case, the noisiest types of aircrafts are B733, B738 and AT72. The sound level varies from 70 to 85 dBA. The quietest aircrafts are RJ1H and F70. When taking off, the equivalent of the maximum sound level value of these aircrafts does not exceed the authorized limits. The paper describes the causes of noise in aircrafts, the sources of origin and the impact of noise on humans and the environment.Article in Lithuanian

  17. Space life sciences: structure and dynamics of the global space radiation field at aircraft altitudes.

    Science.gov (United States)

    2003-01-01

    This issue is devoted to research papers on the radiation environment encountered by aircraft crew members and the flying public, both of which are exposed to a higher than average radiation dose. Two types of space radiation are considered: galactic cosmic radiation and solar activity. The papers include reviews on atmospheric ionization radiation, the factors controlling this radiation, the modeling of this radiation, and measurements made on board specific aircraft flights during solar minimum and solar maximum conditions, and during the major solar proton events that occurred in 1989 and 2001.

  18. Tropical Cyclone Precipitation Types and Electrical Field Information Observed by High Altitude Aircraft Instrumentation

    Science.gov (United States)

    Hood, Robbie E.; Blakeslee, Richard; Cecil, Daniel; LaFontaine, Frank J.; Heymsfield, Gerald; Marks, Frank

    2004-01-01

    During the 1998 and 200 1 hurricane seasons of the Atlantic Ocean Basin, the Advanced Microwave Precipitation Radiometer (AMPR), the ER-2 Doppler (EDOP) radar, and the Lightning Instrument Package (LIP) were flown aboard the National Aeronautics and Space Administration (NASA) ER-2 high altitude aircraft as part of the Third Convection And Moisture Experiment (CAMEX-3) and the Fourth Convection And Moisture Experiment (CAMEX-4). Several hurricanes and tropical storms were sampled during these experiments. A rainfall screening technique has been developed using AMPR passive microwave observations of these tropical cyclones (TC) collected at frequencies of 10.7, 19.35,37.1, and 85.5 GHz and verified using vertical profiles of EDOP reflectivity and lower altitude horizontal reflectivity scam collected by the National Oceanic and Atmospheric Administration (NOM) P-3 radar. Matching the rainfall classification results with coincident electrical field information collected by the LIP readily identifl convective rain regions within the TC precipitation fields. Strengths and weaknesses of the rainfall classification procedure will be discussed as well as its potential as a real-time analysis tool for monitoring vertical updrafl strength and convective intensity from a remotely operated or uninhabited aerial vehicle.

  19. Dynamics modeling and control of a transport aircraft for ultra-low altitude airdrop

    Directory of Open Access Journals (Sweden)

    Liu Ri

    2015-04-01

    Full Text Available The nonlinear aircraft model with heavy cargo moving inside is derived by using the separation body method, which can describe the influence of the moving cargo on the aircraft attitude and altitude accurately. Furthermore, the nonlinear system is decoupled and linearized through the input–output feedback linearization method. On this basis, an iterative quasi-sliding mode (SM flight controller for speed and pitch angle control is proposed. At the first-level SM, a global dynamic switching function is introduced thus eliminating the reaching phase of the sliding motion. At the second-level SM, a nonlinear function with the property of “smaller errors correspond to bigger gains and bigger errors correspond to saturated gains” is designed to form an integral sliding manifold, and the overcompensation of the integral term to big errors is weakened. Lyapunov-based analysis shows that the controller with strong robustness can reject both constant and time-varying model uncertainties. The performance of the proposed control strategy is verified in a maximum load airdrop mission.

  20. Development of High Altitude UAV Weather Radars for Hurricane Research

    Science.gov (United States)

    Heymsfield, Gerald; Li, Li-Hua

    2005-01-01

    A proposed effort within NASA called (ASHE) over the past few years was aimed at studying the genesis of tropical disturbances off the east coast of Africa. This effort was focused on using an instrumented Global Hawk UAV with high altitude (%Ok ft) and long duration (30 h) capability. While the Global Hawk availability remains uncertain, development of two relevant instruments, a Doppler radar (URAD - UAV Radar) and a backscatter lidar (CPL-UAV - Cloud Physics Lidar), are in progress. The radar to be discussed here is based on two previous high-altitude, autonomously operating radars on the NASA ER-2 aircraft, the ER-2 Doppler Radar (EDOP) at X-band (9.6 GHz), and the Cloud Radar System (CRS) at W- band (94 GHz). The nadir-pointing EDOP and CRS radars profile vertical reflectivity structure and vertical Doppler winds in precipitation and clouds, respectively. EDOP has flown in all of the CAMEX flight series to study hurricanes over storms such as Hurricanes Bonnie, Humberto, Georges, Erin, and TS Chantal. These radars were developed at Goddard over the last decade and have been used for satellite algorithm development and validation (TRMM and Cloudsat), and for hurricane and convective storm research. We describe here the development of URAD that will measure wind and reflectivity in hurricanes and other weather systems from a top down, high-altitude view. URAD for the Global Hawk consists of two subsystems both of which are at X-band (9.3-9.6 GHz) and Doppler: a nadir fixed-beam Doppler radar for vertical motion and precipitation measurement, and a Conical scanning radar for horizontal winds in cloud and at the surface, and precipitation structure. These radars are being designed with size, weight, and power consumption suitable for the Global Hawk and other UAV's. The nadir radar uses a magnetron transmitter and the scanning radar uses a TWT transmitter. With conical scanning of the radar at a 35" incidence angle over an ocean surface in the absence of

  1. Airborne remote sensing of cloud properties with the German research aircraft HALO

    OpenAIRE

    Van Hagen, Martin; Hirsch, Lutz; Konow, Heike; Mech, Mario; Orlandi, Emiliano; Crewell, Susanne; Groß, Silke; Fix, Andreas; Wirth, Martin

    2014-01-01

    The new German research aircraft HALO (High Altitude Long range) can be equipped with a remote sensing payload to study cloud properties and water vapor profiles of the atmosphere. This package, first flown during the NARVAL (Next‐generation Aircraft Remote sensing for VALidation studies) mission in December 2013 and January 2014, consists of a cloud radar, microwave radiometers and a lidar system. HALO is a for atmospheric measurements modified Gulfstream G550 business jet with a...

  2. Aircraft

    Science.gov (United States)

    Hibbs, Bart D.; Lissaman, Peter B. S.; Morgan, Walter R.; Radkey, Robert L.

    1998-01-01

    This disclosure provides a solar rechargeable aircraft that is inexpensive to produce, is steerable, and can remain airborne almost indefinitely. The preferred aircraft is a span-loaded flying wing, having no fuselage or rudder. Travelling at relatively slow speeds, and having a two-hundred foot wingspan that mounts photovoltaic cells on most all of the wing's top surface, the aircraft uses only differential thrust of its eight propellers to turn. Each of five sections of the wing has one or more engines and photovoltaic arrays, and produces its own lift independent of the other sections, to avoid loading them. Five two-sided photovoltaic arrays, in all, are mounted on the wing, and receive photovoltaic energy both incident on top of the wing, and which is incident also from below, through a bottom, transparent surface. The aircraft is capable of a top speed of about ninety miles per hour, which enables the aircraft to attain and can continuously maintain altitudes of up to sixty-five thousand feet. Regenerative fuel cells in the wing store excess electricity for use at night, such that the aircraft can sustain its elevation indefinitely. A main spar of the wing doubles as a pressure vessel that houses hydrogen and oxygen gasses for use in the regenerative fuel cell. The aircraft has a wide variety of applications, which include weather monitoring and atmospheric testing, communications, surveillance, and other applications as well.

  3. Tropical deep convective life cycle: Cb-anvil cloud microphysics from high altitude aircraft observations

    Directory of Open Access Journals (Sweden)

    W. Frey

    2014-05-01

    Full Text Available The case study presented here focusses on the life cycle of clouds in a tropical deep convective system. During the SCOUT-O3 campaign from Darwin, Northern Australia, the Hector storm system has been probed by the Geophysica high altitude aircraft. Clouds were observed by in situ particle probes, a backscatter sonde, and a miniature lidar. Additionally, aerosol number concentrations have been measured. On 30 November 2005 a double flight took place and Hector was probed throughout its life cycle in its developing, mature, and dissipating stage. The two flights were four hours apart and focussed on the anvil region of Hector in altitudes between 10.5 km and 18.8 km (i.e. above 350 K potential temperature. Trajectory calculations and ozone measurements have been used to identify that the same cloud air masses have been probed in both flights. The size distributions derived from the measurements not only show a change with increasing altitude but also with the evolution of Hector. Clearly different aerosol to cloud particle ratios as well as varying ice crystal morphology have been found for the different development stages of Hector, indicating a change in freezing mechanisms. The development phase exhibits the smallest ice particles (up to 300 μm with a rather uniform morphology. This is indicative for rapid glaciation during Hector's development. Sizes of ice crystals are largest in the mature stage (larger 1.6 mm and even exceed those of some continental tropical deep convective clouds, also in their number concentrations. The backscatter properties and particle images show a change from frozen droplets in the developing phase to rimed and aggregated particles. The clouds in the dissipating stage have a large vertical extend (roughly 6 km though optically thin and persist for at least 6 h. This poses a high potential for affecting the tropical tropopause layer background conditions regarding humidity, e.g. through facilitating subvisible

  4. Ageing aircraft research in the Netherlands

    Science.gov (United States)

    Dejonge, J. B.; Bartelds, G.

    1992-01-01

    The problems of aging aircraft are worldwide. Hence, international cooperative actions to overcome or prevent problems should be taken. The Federal Aviation Administration (FAA) and the Netherlands Civil Aviation Department (RLD) signed a Memorandum of Cooperation in the area of structural integrity, with specific reference to research on problems in the area of aging aircraft. Here, an overview is given of aging research that is going on in the Netherlands. The work described is done largely at the National Aerospace Laboratory; much of the research is part of the forementioned cooperative agreement.

  5. The NASA Airborne Tropical TRopopause EXperiment (ATTREX):High-Altitude Aircraft Measurements in the Tropical Western Pacific

    Science.gov (United States)

    Jensen, E. J.; Pfister, L.; Jordan, D. E.; Bui, T. V.; Ueyama, R.; Singh, H. B.; Lawson, P.; Thornberry, T.; Diskin, G.; McGill, M.; Pittman, J.; Atlas, E.; Kim, J.

    2016-01-01

    The February through March 2014 deployment of the NASA Airborne Tropical TRopopause EXperiment (ATTREX) provided unique in situ measurements in the western Pacific Tropical Tropopause Layer (TTL). Six flights were conducted from Guam with the long-range, high-altitude, unmanned Global Hawk aircraft. The ATTREX Global Hawk payload provided measurements of water vapor, meteorological conditions, cloud properties, tracer and chemical radical concentrations, and radiative fluxes. The campaign was partially coincident with the CONTRAST and CAST airborne campaigns based in Guam using lower-altitude aircraft The ATTREX dataset is being used for investigations of TTL cloud, transport, dynamical, and chemical processes as well as for evaluation and improvement of global-model representations of TTL processes.

  6. The NASA Earth Research-2 (ER-2) Aircraft: A Flying Laboratory for Earth Science Studies

    Science.gov (United States)

    Navarro, Robert

    2007-01-01

    The National Aeronautics and Space Administration Dryden Flight Research Center, Edwards, California, has two Lockheed Martin Corporation (Bethesda, Maryland) Earth Research-2 (ER2) aircraft that serve as high-altitude and long-range flying laboratories. The ER-2 aircraft has been successfully utilized to conduct scientific studies of stratospheric and tropospheric chemistry, land-use mapping, disaster assessment, preliminary testing and calibration and validation of satellite sensors. The research missions for the ER-2 aircraft are planned, implemented, and managed by the Dryden Flight Research Center Science Mission Directorate. Maintenance and instrument payload integration is conducted by Dryden personnel. The ER-2 aircraft provides experimenters with a wide array of payload accommodations areas with suitable environment control with required electrical and mechanical interfaces. Missions may be flown out of Dryden or from remote bases worldwide, according to research requirements. The NASA ER-2 aircraft is utilized by a variety of customers, including U.S. Government agencies, civilian organizations, universities, and state governments. The combination of the ER-2 aircraft s range, endurance, altitude, payload power, payload volume and payload weight capabilities complemented by a trained maintenance and operations team provides an excellent and unique platform system to the science community and other customers.

  7. Solar Radiation Measurements Onboard the Research Aircraft HALO

    Science.gov (United States)

    Lohse, I.; Bohn, B.; Werner, F.; Ehrlich, A.; Wendisch, M.

    2014-12-01

    Airborne measurements of the separated upward and downward components of solar spectral actinic flux densities for the determination of photolysis frequencies and of upward nadir spectral radiance were performed with the HALO Solar Radiation (HALO-SR) instrument package onboard the High Altitude and Long Range Research Aircraft (HALO). The instrumentation of HALO-SR is characterized and first measurement data from the Next-generation Aircraft Remote-Sensing for Validation Studies (NARVAL) campaigns in 2013 and 2014 are presented. The measured data are analyzed in the context of the retrieved microphysical and optical properties of clouds which were observed underneath the aircraft. Detailed angular sensitivities of the two optical actinic flux receivers were determined in the laboratory. The effects of deviations from the ideal response are investigated using radiative transfer calculations of atmospheric radiance distributions under various atmospheric conditions and different ground albedos. Corresponding correction factors are derived. Example photolysis frequencies are presented, which were sampled in the free troposphere and lower stratosphere over the Atlantic Ocean during the 2013/14 HALO NARVAL campaigns. Dependencies of photolysis frequencies on cloud cover, flight altitude and wavelength range of the photolysis process are investigated. Calculated actinic flux densities in the presence of clouds benefit from the measured spectral radiances. Retrieved cloud optical thicknesses and effective droplet radii are used as model input for the radiative transfer calculations. By comparison with the concurrent measurements of actinic flux densities the retrieval approach is validated. Acknowledgements: Funding by the Deutsche Forschungsgemeinschaft within the priority program HALO (BO 1580/4-1, WE 1900/21-1) is gratefully acknowledged.

  8. An empirical approach to the measurement of the cosmic radiation field at jet aircraft altitudes

    CERN Document Server

    Green, A R; Lewis, B J; Kitching, F; McCall, M J; Desormeaux, M; Butler, A A

    2005-01-01

    Researchers at the Royal Military College of Canada have accumulated extensive dose measurements performed at jet altitudes on over 160 flights and with a wide variety of detectors including a tissue equivalent proportional counter (TEPC), a smart wide energy neutron detection instrument (SWENDI), bubble detectors, thermoluminescent detectors (TLD) and an ion chamber. The summation of the individual low and high LET results from the latter equipment compared successfully to those from the TEPC on each flight. The data from these numerous worldwide flights have been encapsulated into a program that calculates the radiation dose for any flight in the world at any period in the solar cycle. This experimentally based program, Predictive Code for AIRcrew Exposure (PCAIRE) has been designed to be used by the airline industry to meet national dosimetry requirements. In Canada, for example, such a code can be used, supported by periodic measurements. With this latter requirement in mind and a desire to decrease equip...

  9. Impacts of alternative fuels in aviation on microphysical aerosol properties and predicted ice nuclei concentration at aircraft cruise altitude

    Science.gov (United States)

    Weinzierl, B.; D'Ascoli, E.; Sauer, D. N.; Kim, J.; Scheibe, M.; Schlager, H.; Moore, R.; Anderson, B. E.; Ullrich, R.; Mohler, O.; Hoose, C.

    2015-12-01

    In the past decades air traffic has been substantially growing affecting air quality and climate. According to the International Civil Aviation Authority (ICAO), in the next few years world passenger and freight traffic is expected to increase annually by 6-7% and 4-5%, respectively. One possibility to reduce aviation impacts on the atmosphere and climate might be the replacement of fossil fuels by alternative fuels. However, so far the effects of alternative fuels on particle emissions from aircraft engines and their ability to form contrails remain uncertain. To study the effects of alternative fuels on particle emissions and the formation of contrails, the Alternative Fuel Effects on Contrails and Cruise Emissions (ACCESS) field experiment was conducted in California. In May 2014, the DLR Falcon 20 and the NASA HU-25 jet aircraft were instrumented with an extended aerosol and trace gas payload probing different types of fuels including JP-8 and JP-8 blended with HEFA (Hydroprocessed Esters and Fatty Acids) while the NASA DC8 aircraft acted as the source aircraft for ACCESS-2. Emission measurements were taken in the DC8 exhaust plumes at aircraft cruise level between 9-12 km altitude and at distances between 50 m and 20 km behind the DC8 engines. Here, we will present results from the ACCESS-2 aerosol measurements which show a 30-60% reduction of the non-volatile (mainly black carbon) particle number concentration in the aircraft exhaust for the HEFA-blend compared to conventional JP-8 fuel. Size-resolved particle emission indices show the largest reductions for larger particle sizes suggesting that the HEFA blend contains fewer and smaller black carbon particles. We will combine the airborne measurements with a parameterization of deposition nucleation developed during a number of ice nucleation experiments at the AIDA chamber in Karlsruhe and discuss the impact of alternative fuels on the abundance of potential ice nuclei at cruise conditions.

  10. Aviation industry-research in aircraft finance

    OpenAIRE

    Ehrenthal, Joachim C.F.

    2010-01-01

    Aircraft values are key to aircraft financing decisions: Aircraft values act as a source of security for providers of debt capital and lessors failing to re-place aircraft, and as a source of upside potential to equity investors. Yet, aircraft values cannot be precisely and continuously monitored. This is because neither actual primary nor secondary aircraft transaction prices are disclosed. Various types of third party valuation estimates exist, but relying solely on third party appraisa...

  11. Neutrons from thunderstorms at low atmospheric altitudes and related doses at aircraft

    International Nuclear Information System (INIS)

    We conduct a simulation of thunderstorm neutron flashes at the lowest atmospheric altitudes below 10 km. The neutron generation mechanism is based on the nowadays conventional idea of possibility for photonuclear reactions to proceed on the atmospheric components owing to TGF photons. Our modeling includes generation of neutrons from TGF and their further propagation with account of interaction with background nuclei. Using the calculation results we investigate the neutron flux properties with respect to problem of their registration, and predict the radiation environment caused by thunderstorm neutrons on altitudes of civil airflights. It is shown, that good conditions for the neutron flashes observation are provided from the 3 km altitude, and, possibly, the neutrons can be registered at ground level. We also found that thunderstorm-neutron-related effective dose can reach the value of 0.5 mSv in the region close to the TGF source if it is located at an altitude of 10 km.

  12. Recent Progress in Aircraft Noise Research

    Science.gov (United States)

    Envia, Edmane; Thomas, Russell

    2007-01-01

    An overview of the acoustics research at NASA under the Subsonic Fixed Wing project is given. The presentation describes the rationale behind the noise reduction goals of the project in the context of the next generation air transportation system, and the emphasis placed on achieving these goals through a combination of the in-house and collaborative efforts with industry, universities and other government agencies. The presentation also describes the in-house research plan which is focused on the development of advanced noise and flow diagnostic techniques, next generation noise prediction tools, and novel noise reduction techniques that are applicable across a wide range of aircraft.

  13. Correction of static pressure on a research aircraft in accelerated flight using differential pressure measurements

    Directory of Open Access Journals (Sweden)

    A. R. Rodi

    2012-11-01

    Full Text Available A method is described that estimates the error in the static pressure measurement on an aircraft from differential pressure measurements on the hemispherical surface of a Rosemount model 858AJ air velocity probe mounted on a boom ahead of the aircraft. The theoretical predictions for how the pressure should vary over the surface of the hemisphere, involving an unknown sensitivity parameter, leads to a set of equations that can be solved for the unknowns – angle of attack, angle of sideslip, dynamic pressure and the error in static pressure – if the sensitivity factor can be determined. The sensitivity factor was determined on the University of Wyoming King Air research aircraft by comparisons with the error measured with a carefully designed sonde towed on connecting tubing behind the aircraft – a trailing cone – and the result was shown to have a precision of about ±10 Pa over a wide range of conditions, including various altitudes, power settings, and gear and flap extensions. Under accelerated flight conditions, geometric altitude data from a combined Global Navigation Satellite System (GNSS and inertial measurement unit (IMU system are used to estimate acceleration effects on the error, and the algorithm is shown to predict corrections to a precision of better than ±20 Pa under those conditions. Some limiting factors affecting the precision of static pressure measurement on a research aircraft are discussed.

  14. the APL Balloonborne High Altitude Research Platform (HARP)

    Science.gov (United States)

    Adams, D.; Arnold, S.; Bernasconi, P.

    2015-09-01

    The Johns Hopkins University Applied Physics Laboratory (APL) has developed and demonstrated a multi-purpose stratospheric balloonborne gondola known as the High Altitude Research Platform (HARP). HARP provides the power, mechanical supports, thermal control, and data transmission for multiple forms of high-altitude scientific research equipment. The platform has been used for astronomy, cosmology and heliophysics experiments but can also be applied to atmospheric studies, space weather and other forms of high altitude research. HARP has executed five missions. The first was Flare Genesis from Antarctica in 1993 and the most recent was the Balloon Observation Platform for Planetary Science (BOPPS) from New Mexico in 2014. HARP will next be used to perform again the Stratospheric Terahertz Observatory mission, a mission that it first performed in 2009. The structure, composed of an aluminum framework is designed for easy transport and field assembly while providing ready access to the payload and supporting avionics. A light-weighted structure, capable of supporting Ultra-Long Duration Balloon (ULDB) flights that can last more than 100 days is available. Scientific research payloads as heavy as 600 kg (1322 pounds) and requiring up to 800 Watts electrical power can be supported. The platform comprises all subsystems required to support and operate the science payload, including both line-of-sight (LOS) and over-the-horizon (0TH) telecommunications, the latter provided by Iridium Pilot. Electrical power is produced by solar panels for multi-day missions and batteries for single-day missions. The avionics design is primarily single-string; however, use of ruggedized industrial components provides high reliability. The avionics features a Command and Control (C&C) computer and a Pointing Control System (PCS) computer housed within a common unpressurized unit. The avionics operates from ground pressure to 2 Torr and over a temperature range from —30 C to +85 C

  15. UNOLS now oversees research aircraft facilities for ocean science

    OpenAIRE

    Bane, John M.; Bluth, Robert; Flagg, Charles; Jonsson, Haflidi; Melville, W. Kendall; Prince, Mike; Riemer, Daniel

    2004-01-01

    In recognition of the increasing importance and value of aircraft as observational platforms in oceanographic research, the University National Oceanographic Laboratory System (UNOLS) has established the Scientific Committee for Oceanographic Aircraft Research (SCOAR).SCOAR aims to establish procedures for research aircraft that follow the present UNOLS practices for research vessel use, with the goal of making it understandable, and easy, and thus desirable, for...

  16. An Undergraduate-Built Prototype Altitude Determination System (PADS) for High Altitude Research Balloons.

    Science.gov (United States)

    Verner, E.; Bruhweiler, F. C.; Abot, J.; Casarotto, V.; Dichoso, J.; Doody, E.; Esteves, F.; Morsch Filho, E.; Gonteski, D.; Lamos, M.; Leo, A.; Mulder, N.; Matubara, F.; Schramm, P.; Silva, R.; Quisberth, J.; Uritsky, G.; Kogut, A.; Lowe, L.; Mirel, P.; Lazear, J.

    2014-12-01

    In this project a multi-disciplinary undergraduate team from CUA, comprising majors in Physics, Mechanical Engineering, Electrical Engineering, and Biology, design, build, test, fly, and analyze the data from a prototype attitude determination system (PADS). The goal of the experiment is to determine if an inexpensive attitude determination system could be built for high altitude research balloons using MEMS gyros. PADS is a NASA funded project, built by students with the cooperation of CUA faculty, Verner, Bruhweiler, and Abot, along with the contributed expertise of researchers and engineers at NASA/GSFC, Kogut, Lowe, Mirel, and Lazear. The project was initiated through a course taught in CUA's School of Engineering, which was followed by a devoted effort by students during the summer of 2014. The project is an experiment to use 18 MEMS gyros, similar to those used in many smartphones, to produce an averaged positional error signal that could be compared with the motion of the fixed optical system as recorded through a string of optical images of stellar fields to be stored on a hard drive flown with the experiment. The optical system, camera microprocessor, and hard drive are enclosed in a pressure vessel, which maintains approximately atmospheric pressure throughout the balloon flight. The experiment uses multiple microprocessors to control the camera exposures, record gyro data, and provide thermal control. CUA students also participated in NASA-led design reviews. Four students traveled to NASA's Columbia Scientific Balloon Facility in Palestine, Texas to integrate PADS into a large balloon gondola containing other experiments, before being shipped, then launched in mid-August at Ft. Sumner, New Mexico. The payload is to fly at a float altitude of 40-45,000 m, and the flight last approximately 15 hours. The payload is to return to earth by parachute and the retrieved data are to be analyzed by CUA undergraduates. A description of the instrument is presented

  17. Correction of static pressure on a research aircraft in accelerated flight using differential pressure measurements

    Directory of Open Access Journals (Sweden)

    A. R. Rodi

    2012-05-01

    Full Text Available Geometric altitude data from a combined Global Navigation Satellite System (GNSS and inertial measurement unit (IMU system on the University of Wyoming King Air research aircraft are used to estimate acceleration effects on static pressure measurement. Using data collected during periods of accelerated flight, comparison of measured pressure with that derived from GNSS/IMU geometric altitude show that errors exceeding 150 Pa can occur which is significant in airspeed and atmospheric air motion determination. A method is developed to predict static pressure errors from analysis of differential pressure measurements from a Rosemount model 858 differential pressure air velocity probe. The method was evaluated with a carefully designed probe towed on connecting tubing behind the aircraft – a "trailing cone" – in steady flight, and shown to have a precision of about ±10 Pa over a wide range of conditions including various altitudes, power settings, and gear and flap extensions. Under accelerated flight conditions, compared to the GNSS/IMU data, this algorithm predicts corrections to a precision of better than ±20 Pa. Some limiting factors affecting the precision of static pressure measurement on a research aircraft are examined.

  18. HAI: A new TDLAS hygrometer for the HALO research aircraft

    Science.gov (United States)

    Klostermann, Tim; Afchine, Armin; Barthel, Jochen; Höh, Matthias; Wagner, Steven; Witzel, Oliver; Saathoff, Harald; Schiller, Cornelius; Ebert, Volker

    2010-05-01

    Water vapor is the most important greenhouse gas in the Earth's atmosphere and a key component for several physical and chemical processes. Therefore it is a key parameter to be measured during most research campaigns. The Hygrometer for Atmospheric Investigations (HAI) is especially designed for operations on the research aircraft HALO (High Altitude and LOng range research aircraft). HAI permits both, the in-situ measurement of water vapor with an open-path cell and the measurement of total water with an extractive close-path absorption cell. We are using TDLAS (Tunable Diode Laser Absorption Spectroscopy) in two water absorption bands with different line strength to increase the dynamical range. With this concept it is possible to measure from the middle troposphere up to the stratosphere. The open-path cell outside of the fuselage consists of a robust, aerodynamically designed aluminum structure with a single integrated White-cell for both laser beams. Although the mirror separation is only 15cm the cell allows an open absorption path of 4.8m. The detection of higher H2O concentrations is realized with a fiber coupled 1.4µm DFB diode laser. Inside the UTLS layer were small concentrations in the low ppm range are common, we employ up to 20 times stronger fundamental ro-vibration lines of the water molecule near 2.6µm. To supply this, the fiber coupled 2.6µm laser setup was developed and is a part of the HAI. Both detection wavelengths are introduced in the same open path cell via glass fibers which provide water measurements with a minimum of parasitic absorption. We will present the spectrometer design for high-quality airborne water measurements. Furthermore, first laboratory measurements will be shown.

  19. An Overview of NASA's Subsonic Research Aircraft Testbed (SCRAT)

    Science.gov (United States)

    Baumann, Ethan; Hernandez, Joe; Ruhf, John C.

    2013-01-01

    National Aeronautics and Space Administration Dryden Flight Research Center acquired a Gulfstream III (GIII) aircraft to serve as a testbed for aeronautics flight research experiments. The aircraft is referred to as SCRAT, which stands for SubsoniC Research Aircraft Testbed. The aircraft's mission is to perform aeronautics research; more specifically raising the Technology Readiness Level (TRL) of advanced technologies through flight demonstrations and gathering high-quality research data suitable for verifying the technologies, and validating design and analysis tools. The SCRAT has the ability to conduct a range of flight research experiments throughout a transport class aircraft's flight envelope. Experiments ranging from flight-testing of a new aircraft system or sensor to those requiring structural and aerodynamic modifications to the aircraft can be accomplished. The aircraft has been modified to include an instrumentation system and sensors necessary to conduct flight research experiments along with a telemetry capability. An instrumentation power distribution system was installed to accommodate the instrumentation system and future experiments. An engineering simulation of the SCRAT has been developed to aid in integrating research experiments. A series of baseline aircraft characterization flights has been flown that gathered flight data to aid in developing and integrating future research experiments. This paper describes the SCRAT's research systems and capabilities.

  20. Aircraft Turbine Engine Control Research at NASA Glenn Research Center

    Science.gov (United States)

    Garg, Sanjay

    2014-01-01

    This lecture will provide an overview of the aircraft turbine engine control research at NASA (National Aeronautics and Space Administration) Glenn Research Center (GRC). A brief introduction to the engine control problem is first provided with a description of the current state-of-the-art control law structure. A historical aspect of engine control development since the 1940s is then provided with a special emphasis on the contributions of GRC. The traditional engine control problem has been to provide a means to safely transition the engine from one steady-state operating point to another based on the pilot throttle inputs. With the increased emphasis on aircraft safety, enhanced performance and affordability, and the need to reduce the environmental impact of aircraft, there are many new challenges being faced by the designers of aircraft propulsion systems. The Controls and Dynamics Branch (CDB) at GRC is leading and participating in various projects in partnership with other organizations within GRC and across NASA, other government agencies, the U.S. aerospace industry, and academia to develop advanced propulsion controls and diagnostics technologies that will help meet the challenging goals of NASA programs under the Aeronautics Research Mission. The second part of the lecture provides an overview of the various CDB technology development activities in aircraft engine control and diagnostics, both current and some accomplished in the recent past. The motivation for each of the research efforts, the research approach, technical challenges and the key progress to date are summarized. The technologies to be discussed include system level engine control concepts, gas path diagnostics, active component control, and distributed engine control architecture. The lecture will end with a futuristic perspective of how the various current technology developments will lead to an Intelligent and Autonomous Propulsion System requiring none to very minimum pilot interface

  1. The Eddy Experiment: accurate GNSS-R ocean altimetry from low altitude aircraft

    CERN Document Server

    Ruffini, G; Caparrini, M; Germain, O; Martin-Neira, M

    2004-01-01

    During the Eddy Experiment, two synchronous GPS receivers were flown at 1 km altitude to collect L1 signals and their reflections from the sea surface for assessment of altimetric precision and accuracy. Wind speed (U10) was around 10 m/s, and SWH up to 2 m. A geophysical parametric waveform model was used for retracking and estimation of the lapse between the direct and reflected signals with a 1-second precision of 3 m. The lapse was used to estimate the SSH along the track using a differential model. The RMS error of the 20 km averaged GNSS-R absolute altimetric solution with respect to Jason-1 SSH and a GPS buoy measurement was of 10 cm, with a 2 cm mean difference. Multipath and retracking parameter sensitivity due to the low altitude are suspected to have degraded accuracy. This result provides an important milestone on the road to a GNSS-R mesoscale altimetry space mission.

  2. Reference energy-altitude descent guidance: Simulator evaluation. [aircraft descent and fuel conservation

    Science.gov (United States)

    Abbot, K. H.; Knox, C. E.

    1985-01-01

    Descent guidance was developed to provide a pilot with information to ake a fuel-conservative descent and cross a designated geographical waypoint at a preselected altitude and airspeed. The guidance was designed to reduce fuel usage during the descent and reduce the mental work load associated with planning a fuel-conservative descent. A piloted simulation was conducted to evaluate the operational use of this guidance concept. The results of the simulation tests show that the use of the guidance reduced fuel consumption and mental work load during the descent. Use of the guidance also decreased the airspeed error, but had no effect on the altitude error when the designated waypoint was crossed. Physical work load increased with the use of the guidance, but remained well within acceptable levels. The pilots found the guidance easy to use as presented and reported that it would be useful in an operational environment.

  3. Research on aircraft emissions. Need for future work

    Energy Technology Data Exchange (ETDEWEB)

    Schmitt, A. [German Aerospace Establishment, Cologne (Germany). Transport Research Div.

    1997-12-31

    Reflecting the present status of the research on aircraft emissions and their impacts upon the atmosphere, task-fields for a work programme for the research on aircraft emissions can be derived. Most important measures are to support the efforts to define adequate reduction measures, and (with highest priority) scenario-writing for the long-term development in aircraft emissions, to be able to include into the decision making process the aspect of in-time-reaction against unwanted future. Besides that, a steady monitoring of global aircraft emissions will be necessary. (author) 5 refs.

  4. The GNSS-R Eddy Experiment I: Altimetry from Low Altitude Aircraft

    CERN Document Server

    Ruffini, G; Caparrini, M; Germain, O; Martin-Neira, M

    2003-01-01

    We report results from the Eddy Experiment, where a synchronous GPS receiver pair was flown on an aircraft to collect sampled L1 signals and their reflections from the sea surface to investigate the altimetric accuracy of GNSS-R. During the experiment, surface wind speed (U10) was of the order of 10 m/s, and significant wave heights of up to 2 m, as discussed further in a companion paper. After software tracking of the two signals through despreading of the GPS codes, a parametric waveform model containing the description of the sea surface conditions has been used to fit the waveforms (retracking) and estimate the temporal lapse between the direct GPS signals and their reflections. The estimated lapses have then been used to estimate the sea surface height (SSH) along the aircraft track using a differential geometric model. As expected, the precision of GNSS-R ranges was of 3 m after 1 second integration. More importantly, the accuracy of the GNSS-R altimetric solution with respect to Jason-1 SSH and in situ...

  5. Unmanned Aircraft System (UAS) Traffic Management (UTM): Enabling Civilian Low-Altitude Airspace and Unmanned Aerial System Operations

    Science.gov (United States)

    Kopardekar, Parimal Hemchandra

    2016-01-01

    Just a year ago we laid out the UTM challenges and NASA's proposed solutions. During the past year NASA's goal continues to be to conduct research, development and testing to identify airspace operations requirements to enable large-scale visual and beyond visual line-of-sight UAS operations in the low-altitude airspace. Significant progress has been made, and NASA is continuing to move forward.

  6. High altitude, a natural research laboratory for the study of cardiovascular physiology and pathophysiology.

    Science.gov (United States)

    Scherrer, Urs; Allemann, Yves; Jayet, Pierre-Yves; Rexhaj, Emrush; Sartori, Claudio

    2010-01-01

    High altitude constitutes an exciting natural laboratory for medical research. Although initially, the aim of high-altitude research was to understand the adaption of the organism to hypoxia and find treatments for altitude-related diseases, during the past decade or so, the scope of this research has broadened considerably. Two important observations led the foundation for the broadening of the scientific scope of high-altitude research. First, high-altitude pulmonary edema represents a unique model that allows studying fundamental mechanisms of pulmonary hypertension and lung edema in humans. Second, the ambient hypoxia associated with high-altitude exposure facilitates the detection of pulmonary and systemic vascular dysfunction at an early stage. Here, we will review studies that, by capitalizing on these observations, have led to the description of novel mechanisms underpinning lung edema and pulmonary hypertension and to the first direct demonstration of fetal programming of vascular dysfunction in humans.

  7. Vertical Cloud Climatology During TC4 Derived from High-Altitude Aircraft Merged Lidar and Radar Profiles

    Science.gov (United States)

    Hlavka, Dennis; Tian, Lin; Hart, William; Li, Lihua; McGill, Matthew; Heymsfield, Gerald

    2009-01-01

    Aircraft lidar works by shooting laser pulses toward the earth and recording the return time and intensity of any of the light returning to the aircraft after scattering off atmospheric particles and/or the Earth s surface. The scattered light signatures can be analyzed to tell the exact location of cloud and aerosol layers and, with the aid of a few optical assumptions, can be analyzed to retrieve estimates of optical properties such as atmospheric transparency. Radar works in a similar fashion except it sends pulses toward earth at a much larger wavelength than lidar. Radar records the return time and intensity of cloud or rain reflection returning to the aircraft. Lidar can measure scatter from optically thin cirrus and aerosol layers whose particles are too small for the radar to detect. Radar can provide reflection profiles through thick cloud layers of larger particles that lidar cannot penetrate. Only after merging the two instrument products can accurate measurements of the locations of all layers in the full atmospheric column be achieved. Accurate knowledge of the vertical distribution of clouds is important information for understanding the Earth/atmosphere radiative balance and for improving weather/climate forecast models. This paper describes one such merged data set developed from the Tropical Composition, Cloud and Climate Coupling (TC4) experiment based in Costa Rica in July-August 2007 using the nadir viewing Cloud Physics Lidar (CPL) and the Cloud Radar System (CRS) on board the NASA ER-2 aircraft. Statistics were developed concerning cloud probability through the atmospheric column and frequency of the number of cloud layers. These statistics were calculated for the full study area, four sub-regions, and over land compared to over ocean across all available flights. The results are valid for the TC4 experiment only, as preferred cloud patterns took priority during mission planning. The TC4 Study Area was a very cloudy region, with cloudy

  8. Wide range operation of advanced low NOx combustors for supersonic high-altitude aircraft gas turbines

    Science.gov (United States)

    Roberts, P. B.; Fiorito, R. J.

    1977-01-01

    An initial rig program tested the Jet Induced Circulation (JIC) and Vortex Air Blast (VAB) systems in small can combustor configurations for NOx emissions at a simulated high altitude, supersonic cruise condition. The VAB combustor demonstrated the capability of meeting the NOx goal of 1.0 g NO2/kg fuel at the cruise condition. In addition, the program served to demonstrate the limited low-emissions range available from the lean, premixed combustor. A follow-on effort was concerned with the problem of operating these lean, premixed combustors with acceptable emissions at simulated engine idle conditions. Various techniques have been demonstrated that allow satisfactory operation on both the JIC and VAB combustors at idle with CO emissions below 20 g/kg fuel. The VAB combustor was limited by flashback/autoignition phenomena at the cruise conditions to a pressure of 8 atmospheres. The JIC combustor was operated up to the full design cruise pressure of 14 atmospheres without encountering an autoignition limitation although the NOx levels, in the 2-3 g NO2/kg fuel range, exceeded the program goal.

  9. High Altitude Long Endurance (HALE) Unmanned Aircraft System (UAS): Pilot Knowledge, Skills and Abilities

    Science.gov (United States)

    2005-01-01

    This report summarizes the initial work accomplished by the ACCESS 5 Human System Integration (HSI) team to identify Unmanned Aircraft System (UAS) Pilot Knowledge, Skill and Ability (KSA), Training and Medical requirements. To derive this information the following tasks were accomplished: a) Mission and Function analyses were performed; b) Applicable FARs and FAA Advisory Circulars (ACs) were reviewed; c) Meetings were conducted with NASA and FAA Human Factors personnel; d) Surveys were completed by ACCESS 5 HSI Working group UA Pilots; e) Coordination meetings were conducted with the ACCESS 5 Policy IPT. The results of these efforts were used to develop a summary of the current qualifications. for an individual to function as a Pilot In Command (PIC) for UAs currently flown by UNITE companies, to develop preliminary Pilot KSAs for each phase of flight, and to delineate preliminary Pilot Training and Medical requirements. These results are to be provided to the Policy IPT to support their development of recommendations for UA Pilot Rating Criteria, training and medical qualifications. It is expected that the initially an instrument rated pilot will be required to serve as the PIC. However, as operational experience is gained, and automation is applied to accomplish various system functions, it is expected that pilot rating criteria could be lessened.

  10. Research on Emerging and Descending Aircraft Noise

    OpenAIRE

    Monika Bartkevičiūtė; Raimondas Grubliauskas

    2013-01-01

    Along with an increase in the aircraft engine power and growth in air traffic, noise level at airports and their surrounding environs significantly increases. Aircraft noise is high level noise spreading within large radius and intensively irritating the human body. Air transport is one of the main sources of noise having a particularly strong negative impact on the environment. The article deals with activities and noises taking place in the largest nationwide Vilnius International Airport.T...

  11. Potential uses of small unmanned aircraft systems (UAS) in weed research

    DEFF Research Database (Denmark)

    Rasmussen, Jesper; Nielsen, Jon; Garcia Ruiz, Francisco Jose;

    2013-01-01

    Small unmanned aerial systems (UAS) with cameras have not been adopted in weed research, but offer low-cost sensing with high flexibility in terms of spatial resolution. A small rotary-wing UAS was tested as part of a search for an inexpensive, user-friendly and reliable aircraft for practical...... in the range from 0.3 to 17.1 mm per pixel. This finding is important because spatial resolution is inversely related to sensing capacity. We captured 20 plots comprising a total of about 0.2 ha in one image at 50 m altitude without losing information about the cultivation impacts on vegetation compared...

  12. Prototype-Technology Evaluator and Research Aircraft Project

    Data.gov (United States)

    National Aeronautics and Space Administration — The Area-I team has developed and flight tested the unmanned Prototype-Technology Evaluation and Research Aircraft or PTERA ("ptera" being Greek for wing, or...

  13. The rotor systems research aircraft - A flying wind tunnel

    Science.gov (United States)

    Linden, A. W.; Hellyar, M. W.

    1974-01-01

    The Sikorsky Aircraft division of United Aircraft Corporation is constructing two uniquely designed Rotor Systems Research Aircraft (RSRA). These aircraft will be used through the 1980's to comparatively test many different types of rotors - articulated, hingeless, teetering, and gimballed, as well as advanced rotor concepts, such as reverse velocity and variable diameter rotors. The RSRA combines a new airframe with existing Sikorsky H-3 (S-61) dynamic components. A force measurement system is incorporated to permit accurate evaluation of significant rotor characteristics. Both rotor and fixed-wing control systems are provided, appropriately integrated for operation in the pure helicopter mode, compound helicopter mode, and fixed-wing mode. The RSRA is the first rotary wing aircraft designed with a crew escape system, including a pyrotechnic system to sever the main rotor blades.

  14. V/STOL tilt rotor aircraft study. Volume 2: Preliminary design of research aircraft

    Science.gov (United States)

    1972-01-01

    A preliminary design study was conducted to establish a minimum sized, low cost V/STOL tilt-rotor research aircraft with the capability of performing proof-of-concept flight research investigations applicable to a wide range of useful military and commercial configurations. The analysis and design approach was based on state-of-the-art methods and maximum use of off-the-shelf hardware and systems to reduce development risk, procurement cost and schedules impact. The rotors to be used are of 26 foot diameter and are the same as currently under construction and test as part of NASA Tilt-Rotor Contract NAS2-6505. The aircraft has a design gross weight of 12,000 lbs. The proposed engines to be used are Lycoming T53-L-13B rated at 1550 shaft horsepower which are fully qualified. A flight test investigation is recommended which will determine the capabilities and limitations of the research aircraft.

  15. NARVAL North - Remote Sensing of Postfrontal Convective Clouds and Precipitation over the North Atlantic with the Research Aircraft HALO

    Science.gov (United States)

    Klepp, Christian; Ament, Felix; Bakan, Stephan; Crewell, Susanne; Hagen, Martin; Hirsch, Lutz; Jansen, Friedhelm; Konow, Heike; Mech, Mario; Pfeilsticker, Klaus; Schäfler, Andreas; Stevens, Bjorn

    2014-05-01

    The new German research aircraft HALO (High Altitude and Long Range Research Aircraft) became recently available for measurement flights in atmospheric research. It's capacity of measuring from a high altitude vertical profiles of all components of atmospheric water - like vapor, liquid and ice, in both cloud and precipitation forms, as well as the aerosol particles upon which cloud droplets form - makes it a unique research platform. The aircraft, equipped with advanced radiometers, radar and lidar technology, the HALO Microwave Package (HAMP), is an initiative by German climate and environmental research institutions and is operated by the German Aerospace Center (DLR). One of the first major missions to exploit the capabilities of HALO was conducted for the NARVAL project (Next-generation Aircraft Remote-Sensing for Validation Studies) during January 2014. After studying subtropical clouds one month before in the first NARVAL phase, the interest of NARVAL North focused on the study of cold air convection and precipitation in the form of rain and snow. Based at Keflavik airport (Iceland), several flights were conducted to examine the specific small-scale precipitation structures behind the backsides of cold fronts over the North Atlantic. This should help to narrow the gap in the understanding of substantial differences between satellite observations and model calculations in such situations. First data analysis of these measurements indicate promising results. The poster will describe the HALO instrument packages as well as the collected observations during the campaign and will present preliminary scientific findings.

  16. Ecological Risk Assessment Framework for Low-Altitude Overflights by Fixed-Wing and Rotary-Wing Military Aircraft

    Energy Technology Data Exchange (ETDEWEB)

    Efroymson, R.A.

    2001-01-12

    This is a companion report to the risk assessment framework proposed by Suter et al. (1998): ''A Framework for Assessment of Risks of Military Training and Testing to Natural Resources,'' hereafter referred to as the ''generic framework.'' The generic framework is an ecological risk assessment methodology for use in environmental assessments on Department of Defense (DoD) installations. In the generic framework, the ecological risk assessment framework of the US Environmental Protection Agency (EPA 1998) is modified for use in the context of (1) multiple and diverse stressors and activities at a military installation and (2) risks resulting from causal chains, e.g., effects on habitat that indirectly impact wildlife. Both modifications are important if the EPA framework is to be used on military installations. In order for the generic risk assessment framework to be useful to DoD environmental staff and contractors, the framework must be applied to specific training and testing activities. Three activity-specific ecological risk assessment frameworks have been written (1) to aid environmental staff in conducting risk assessments that involve these activities and (2) to guide staff in the development of analogous frameworks for other DoD activities. The three activities are: (1) low-altitude overflights by fixed-wing and rotary-wing aircraft (this volume), (2) firing at targets on land, and (3) ocean explosions. The activities were selected as priority training and testing activities by the advisory committee for this project.

  17. NASA Glenn's Contributions to Aircraft Engine Noise Research

    Science.gov (United States)

    Huff, Dennis L.

    2014-01-01

    This presentation reviews engine noise research conducted at the NASA Glenn Research Center over the past 70 years. This report includes a historical perspective of the Center and the facilities used to conduct the research. Major noise research programs are highlighted to show their impact on industry and on the development of aircraft noise reduction technology. Noise reduction trends are discussed, and future aircraft concepts are presented. Since the 1960s, research results show that the average perceived noise level has been reduced by about 20 decibels (dB). Studies also show that, depending on the size of the airport, the aircraft fleet mix, and the actual growth in air travel, another 15 to 17 dB reduction will be required to achieve NASAs long-term goal of providing technologies to limit objectionable noise to the boundaries of an average airport.

  18. Design and simulation of solar powered aircraft for year-round operation at high altitude; Auslegung und Simulation von hochfliegenden, dauerhaft stationierbaren Solardrohnen

    Energy Technology Data Exchange (ETDEWEB)

    Keidel, B.

    2000-05-18

    An unmanned solar powered aircraft configuration called SOLITAIR has been designed. This aircraft is intended to be used as an high altitude long endurance (HALE) sensor platform for year-round operation at intermediate latitudes up to about {+-}55 . For the design studies leading to this aircraft configuration, a software package has been developed which enables an effective design and a proper simulation of the entire solar aircraft system for various flight missions. The performance analysis and the mission simulation showed, that a configuration with large additional solar panels, that can be tilted in order to follow the sun angle during daytime operation appears to be superior to aircraft configurations with wing-mounted solar cells for the desired operational area. In order to examine the basic flight characteristics of the SOLITAIR configuration a remote controlled demonstration model has been built and test flown. [German] In der vorliegenden Arbeit wurden Moeglichkeiten geschaffen, um Gesamtsystemkonfigura-tionen unbemannter hochfliegender Solarflugzeuge fuer unterschiedliche Anwendungsfaelle auszulegen und die Flugleistungen sowie die Missionsfaehigkeit dieser Konfigurationen aufzuzeigen. Mit den geschaffenen und verifizierten Entwicklungswerkzeugen wurde eine Solarflugzeugkonfiguration entworfen und mittels eines Demonstrationsmodells erprobt. Mit dieser Konfiguration kann eine dauerhafte Stationierbarkeit von ca. 55 suedlicher bis 55 noerdlicher Breite erreicht werden. Dies stellt eine bedeutende Erweiterung des bisher fuer moeglich gehaltenen Nutzungsbereiches solcher Flugzeuge dar.

  19. Exploratory flight investigation of aircraft response to the wing vortex wake generated by the augmentor wing jet STOL research aircraft

    Science.gov (United States)

    Jacobsen, R. A.; Drinkwater, F. J., III

    1975-01-01

    A brief exploratory flight program was conducted at Ames Research Center to investigate the vortex wake hazard of a powered-lift STOL aircraft. The study was made by flying an instrumented Cessna 210 aircraft into the wake of the augmentor wing jet STOL research aircraft at separation distances from 1 to 4 n.mi. Characteristics of the wake were evaluated in terms of the magnitude of the upset of the probing aircraft. Results indicated that within 1 n.mi. separation the wake could cause rolling moments in excess of roll control power and yawing moments equivalent to rudder control power of the probe aircraft. Subjective evaluations by the pilots of the Cessna 210 aircraft, supported by response measurements, indicated that the upset caused by the wake of the STOL aircraft was comparable to that of a DC-9 in the landing configuration.

  20. 2D雷达情报组网目标高度估计%Estimation of Aircraft Altitude with 2D Radar Intelligence Networking

    Institute of Scientific and Technical Information of China (English)

    雷雨; 冯新喜; 朱灿彬; 李彬彬

    2011-01-01

    基于WGS-84地球等效参考椭球,构建了较为实际的两部2D雷达组网目标高度观测模型,提出了一种新的雷达情报组网目标高度估计方法,并通过大量仿真分析和对比了该算法的性能.理论分析与仿真证明,该算法模型考虑了雷达电磁波信号在大气中的传播折射问题,以及地球曲率对雷达观测的影响,充分利用了各雷达的量测信息,更贴近雷达观测的实际,能显著提高目标高度估计的精度,并且计算量小、运算速度快,具有一定的工程应用价值.%An effective measurement model of altitude estimation in 2D radar network with 2 sensors which is based on the WGS-84 ellipsoid earth is designed, and a new algorithm of aircraft altitude estimation with 2D radar intelligence networking is presented. Through a lot of simulations and academic analysis, the performance of the algorithm is analyzed thoroughly. The simulation and analysis result shows that the proposed algorithm considers the refraction of electromagnetic wave in the atmosphere, and the effect of the earth curvature to the observations. This algorithm accords to the fact of observation, and made full use of the measurement, so the estimation of Aircraft altitude was improved; together with the less quantity of calculations and the rapid operations, the proposed algorithm has fairly great practical value in engineering application.

  1. Research on uncertainty in measurement assisted alignment in aircraft assembly

    Institute of Scientific and Technical Information of China (English)

    Chen Zhehan; Du Fuzhou; Tang Xiaoqing

    2013-01-01

    Operations in assembling and joining large size aircraft components are changed to novel digital and flexible ways by digital measurement assisted alignment. Positions and orientations (P&O) of aligned components are critical characters which assure geometrical positions and rela-tionships of those components. Therefore, evaluating the P&O of a component is considered nec-essary and critical for ensuring accuracy in aircraft assembly. Uncertainty of position and orientation (U-P&O), as a part of the evaluating result of P&O, needs to be given for ensuring the integrity and credibility of the result; furthermore, U-P&O is necessary for error tracing and quality evaluating of measurement assisted aircraft assembly. However, current research mainly focuses on the process integration of measurement with assembly, and usually ignores the uncer-tainty of measured result and its influence on quality evaluation. This paper focuses on the expres-sion, analysis, and application of U-P&O in measurement assisted alignment. The geometrical and algebraical connotations of U-P&O are presented. Then, an analytical algorithm for evaluating the multi-dimensional U-P&O is given, and the effect factors and characteristics of U-P&O are dis-cussed. Finally, U-P&O is used to evaluate alignment in aircraft assembly for quality evaluating and improving. Cases are introduced with the methodology.

  2. An Indispensable Ingredient: Flight Research and Aircraft Design

    Science.gov (United States)

    Gorn, Michael H.

    2003-01-01

    Flight research-the art of flying actual vehicles in the atmosphere in order to collect data about their behavior-has played a historic and decisive role in the design of aircraft. Naturally, wind tunnel experiments, computational fluid dynamics, and mathematical analyses all informed the judgments of the individuals who conceived of new aircraft. But flight research has offered moments of realization found in no other method. Engineer Dale Reed and research pilot Milt Thompson experienced one such epiphany on March 1, 1963, at the National Aeronautics and Space Administration s Dryden Flight Research Center in Edwards, California. On that date, Thompson sat in the cockpit of a small, simple, gumdrop-shaped aircraft known as the M2-F1, lashed by a long towline to a late-model Pontiac Catalina. As the Pontiac raced across Rogers Dry Lake, it eventually gained enough speed to make the M2-F1 airborne. Thompson braced himself for the world s first flight in a vehicle of its kind, called a lifting body because of its high lift-to-drag ratio. Reed later recounted what he saw:

  3. In-flight control and communication architecture of the GLORIA imaging limb-sounder on atmospheric research aircraft

    Science.gov (United States)

    Kretschmer, E.; Bachner, M.; Blank, J.; Dapp, R.; Ebersoldt, A.; Friedl-Vallon, F.; Guggenmoser, T.; Gulde, T.; Hartmann, V.; Lutz, R.; Maucher, G.; Neubert, T.; Oelhaf, H.; Preusse, P.; Schardt, G.; Schmitt, C.; Schönfeld, A.; Tan, V.

    2015-02-01

    The Gimballed Limb Observer for Radiance Imaging of the Atmosphere (GLORIA), a Fourier transform spectrometer based limb spectral imager, operates on high-altitude research aircraft to study the transit region between the troposphere and the stratosphere. It is one of the most sophisticated systems to be flown on research aircraft in Europe, requiring constant monitoring and human intervention in addition to an automation system. To ensure proper functionality and interoperability on multiple platforms, a flexible control and communication system was laid out. The architectures of the communication system as well as the protocols used are reviewed. The integration of this architecture in the automation process as well as the scientific campaign flight application context are discussed.

  4. In-flight control and communication architecture of the GLORIA imaging limb sounder on atmospheric research aircraft

    Science.gov (United States)

    Kretschmer, E.; Bachner, M.; Blank, J.; Dapp, R.; Ebersoldt, A.; Friedl-Vallon, F.; Guggenmoser, T.; Gulde, T.; Hartmann, V.; Lutz, R.; Maucher, G.; Neubert, T.; Oelhaf, H.; Preusse, P.; Schardt, G.; Schmitt, C.; Schönfeld, A.; Tan, V.

    2015-06-01

    The Gimballed Limb Observer for Radiance Imaging of the Atmosphere (GLORIA), a Fourier-transform-spectrometer-based limb spectral imager, operates on high-altitude research aircraft to study the transit region between the troposphere and the stratosphere. It is one of the most sophisticated systems to be flown on research aircraft in Europe, requiring constant monitoring and human intervention in addition to an automation system. To ensure proper functionality and interoperability on multiple platforms, a flexible control and communication system was laid out. The architectures of the communication system as well as the protocols used are reviewed. The integration of this architecture in the automation process as well as the scientific campaign flight application context are discussed.

  5. In-flight control and communication architecture of the GLORIA imaging limb-sounder on atmospheric research aircraft

    Directory of Open Access Journals (Sweden)

    E. Kretschmer

    2015-02-01

    Full Text Available The Gimballed Limb Observer for Radiance Imaging of the Atmosphere (GLORIA, a Fourier transform spectrometer based limb spectral imager, operates on high-altitude research aircraft to study the transit region between the troposphere and the stratosphere. It is one of the most sophisticated systems to be flown on research aircraft in Europe, requiring constant monitoring and human intervention in addition to an automation system. To ensure proper functionality and interoperability on multiple platforms, a flexible control and communication system was laid out. The architectures of the communication system as well as the protocols used are reviewed. The integration of this architecture in the automation process as well as the scientific campaign flight application context are discussed.

  6. Retrieval assessment using the microwave simulation tool for the High Altitude and LOng range aircraft HALO: humidity, temperature and hydrometeor profiles

    Science.gov (United States)

    Mech, M.; Crewell, S.; Orlandi, E.; Hirsch, L.

    2011-12-01

    New cloud observation techniques are needed to improve our understanding of the impact of clouds on the Earth's water cycle and radiation budget, which still represents one of the largest uncertainties in global and regional climate modelling. An airborne platform for such observation techniques will be provided by the new German research aircraft HALO (High Altitude LOng Range). In early 2013 a dedicated remote sensing mission NARVAL employing the microwave package HAMP (HALO Microwave Package; 36 channels microwave radiometer and 35.5 GHz Doppler radar), wind and water vapour lidar as well as auxiliary measurements will invest cloud systems in the North Atlantic in much higher detail than feasible on space-borne platforms. An advanced set of microwave remote cloud sensing instruments is to be operated on board of HALO. It consists of a cloud radar and a suite of passive radiometers in different frequency bands. The radar MIRA-36 operates at 35.5 GHz. The frequencies for the passive microwave radiometers were selected in allusion to the AMSU-A and -B sounder. In addition to the channels along the 60 GHz oxygen complex measurements along the 118 GHz oxygen line hint at the vertical distribution of liquid water that show a strong emission increase with frequency. This combination can be used for precipitation retrieval. In addition to include channels in the water vapor lines at 22.235 GHz and 183.31 GHz, information about the water vapor distribution throughout the troposphere can be retrieved. By including higher microwave channels sensitive to scattering in the ice phase various precipitation retrieval algorithms can be compared with measurements from HAMP. Retrieval algorithms and potential flight patterns are investigated using a simulation test bed combining cloud model and radiative transfer simulations. Thereby the cloud resolving model simulations and the forward radiative transfer calculations include a one- and two-moment cloud microphysical scheme with

  7. European Commission research on aircraft impacts in the atmosphere

    Energy Technology Data Exchange (ETDEWEB)

    Amanatidis, G.T.; Angeletti, G. [European Commission (CEC), Brussels (Belgium)

    1997-12-31

    Aircraft engines release in the troposphere and lower stratosphere a number of chemical compounds (NO{sub x}, CO{sub 2}, CO, H{sub 2}O, hydrocarbons, sulphur, soot, etc.) which could potentially affect the ozone layer and the climate through chemical, dynamical and radiative changes. The global amount of gases and particles emitted by current subsonic and projected supersonic aircraft fleets can be estimated, but significant uncertainties remain about the fate of these emissions in the atmosphere. The European efforts concerning these potential atmospheric impacts of aircraft emissions are conducted by the Environment and Climate Research Programme of the European Commission (EC) as well as by national programmes of the Member States of the European Union (EU). The European research activities in this field, are described, divided for practical reasons in two periods. The first includes activities supported under the 3. Framework Programme for R and D activities which covered the period from 1992 up to 1996, while the second period has started in early 1996 and is supported under the 4. Framework Programme. (R.P.) 6 refs.

  8. Aircraft measurements of ozone, NOx, CO, and aerosol concentrations in biomass burning smoke over Indonesia and Australia in October 1997: Depleted ozone layer at low altitude over Indonesia

    Science.gov (United States)

    Tsutsumi, Yukitomo; Sawa, Yousuke; Makino, Yukio; Jensen, Jørgen B.; Gras, John L.; Ryan, Brian F.; Diharto, Sri; Harjanto, Hery

    The 1997 El Niño unfolded as one of the most sever El Niño Southern Oscillation (ENSO) events in this century and it coincided with massive biomass burning in the equatorial western Pacific region. To assess the influence on the atmosphere, aircraft observations of trace gases and aerosol were conducted over Kalimantan in Indonesia and Australia. Over Kalimantan in Indonesia, high concentrations of O3, NOx, CO, and aerosols were observed during the flight. Although the aerosol and NOx decreased with altitude, the O3 had the maximum concentration (80.5 ppbv) in the middle layer of the smoke haze and recorded very low concentrations (˜20 ppbv) in the lower smoke layer. This feature was not observed in the Australian smoke. We proposed several hypotheses for the low O3 concentration at low levels over Kalimantan. The most likely are lack of solar radiation and losses at the surface of aerosol particles.

  9. Weather Requirements and Procedures for Step 1: High Altitude Long Endurance (HALE) Unmanned Aircraft System (UAS) Flight Operations in the National Air Space (NAS)

    Science.gov (United States)

    2007-01-01

    This cover sheet is for version 2 of the weather requirements document along with Appendix A. The purpose of the requirements document was to identify and to list the weather functional requirements needed to achieve the Access 5 vision of "operating High Altitude, Long Endurance (HALE) Unmanned Aircraft Systems (UAS) routinely, safely, and reliably in the National Airspace System (NAS) for Step 1." A discussion of the Federal Aviation Administration (FAA) references and related policies, procedures, and standards is provided as basis for the recommendations supported within this document. Additional procedures and reference documentation related to weather functional requirements is also provided for background. The functional requirements and related information are to be proposed to the FAA and various standards organizations for consideration and approval. The appendix was designed to show that sources of flight weather information are readily available to UAS pilots conducting missions in the NAS. All weather information for this presentation was obtained from the public internet.

  10. Theoretical and experimental studies of rectangular duct heat exchangers to be used in a high-altitude subsonic aircraft

    Science.gov (United States)

    Mathias, James Allen

    A unique need exists for heat exchangers that operate efficiently at an altitude of 85,000 feet. The application involves transferring heat to the low pressure ambient air at a low velocity that is in the laminar flow regime. Because it is desired that low pressure ambient air experience a small decrease in pressure, heat exchangers were examined with relatively short flowlengths and the boundary layers of the ambient air may be developing for a significant portion of the flowlength. These unique requirements of heat exchangers prompted an experimental study of compact heat exchangers made with relatively short rectangular fins that formed rectangular ducts. Compact heat exchangers made with rectangular fins were experimentally tested to determine the pressure drop of the air across the heat exchanger and the heat transfer to the air; the experiments were performed with air at Reynolds numbers between 100 and 1000. By placing the experimental apparatus in a chamber that was partially evacuated, experiments were also performed with air at a Reynolds number of approximately 250 at simulated elevated altitudes up to 83,000 feet. The results of the experiments performed at sea level and elevated altitudes compared very well. The results of the experiments that measured the pressure drop of the air determined the additional pressure drop caused by the developing boundary layers. An equation obtained from the data of the pressure drop measurements predicted the entrance length of the developing boundary layers. The Nusselt number of the air was calculated from the data of the heat transfer experiments. The Nusselt number significantly increased of the experiments performed with the boundary layers of the air developing for a significant portion of the rectangular duct. An equation was obtained that predicted the Nusselt number for compact heat exchangers with short flowlengths and with air at low Reynolds numbers. The equation that predicted the Nusselt number and the

  11. A structural design for a hypersonic research aircraft

    Science.gov (United States)

    Jackson, L. R.; Taylor, A. H.

    1976-01-01

    A research aircraft is being studied that has potential for large-scale demonstration of advanced propulsive, structural, and aerodynamic technologies for hypersonic application. Versatility is achieved through a large removable payload bay with removable thermal protection, by removable wings, and by the configuration, which considers engine-airframe integration. Design criteria have been applied to an effective heat-sink structure of Lockalloy (Be-38Al), wherein thermal stress alleviation is a prime consideration in the design. Structural analyses are being performed with the SPAR computer program. Results indicate that no critical problems exist and the resulting structural weight is within initial estimates.

  12. The Pilatus unmanned aircraft system for lower atmospheric research

    Science.gov (United States)

    de Boer, Gijs; Palo, Scott; Argrow, Brian; LoDolce, Gabriel; Mack, James; Gao, Ru-Shan; Telg, Hagen; Trussel, Cameron; Fromm, Joshua; Long, Charles N.; Bland, Geoff; Maslanik, James; Schmid, Beat; Hock, Terry

    2016-04-01

    This paper presents details of the University of Colorado (CU) "Pilatus" unmanned research aircraft, assembled to provide measurements of aerosols, radiation and thermodynamics in the lower troposphere. This aircraft has a wingspan of 3.2 m and a maximum take-off weight of 25 kg, and it is powered by an electric motor to reduce engine exhaust and concerns about carburetor icing. It carries instrumentation to make measurements of broadband up- and downwelling shortwave and longwave radiation, aerosol particle size distribution, atmospheric temperature, relative humidity and pressure and to collect video of flights for subsequent analysis of atmospheric conditions during flight. In order to make the shortwave radiation measurements, care was taken to carefully position a high-quality compact inertial measurement unit (IMU) and characterize the attitude of the aircraft and its orientation to the upward-looking radiation sensor. Using measurements from both of these sensors, a correction is applied to the raw radiometer measurements to correct for aircraft attitude and sensor tilt relative to the sun. The data acquisition system was designed from scratch based on a set of key driving requirements to accommodate the variety of sensors deployed. Initial test flights completed in Colorado provide promising results with measurements from the radiation sensors agreeing with those from a nearby surface site. Additionally, estimates of surface albedo from onboard sensors were consistent with local surface conditions, including melting snow and bright runway surface. Aerosol size distributions collected are internally consistent and have previously been shown to agree well with larger, surface-based instrumentation. Finally the atmospheric state measurements evolve as expected, with the near-surface atmosphere warming over time as the day goes on, and the atmospheric relative humidity decreasing with increased temperature. No directional bias on measured temperature, as might

  13. The pilatus unmanned aircraft system for lower atmospheric research

    Directory of Open Access Journals (Sweden)

    G. de Boer

    2015-11-01

    Full Text Available This paper presents details of the University of Colorado (CU Pilatus unmanned research aircraft, assembled to provide measurements of aerosols, radiation and thermodynamics in the lower troposphere. This aircraft has a wingspan of 3.2 m and a maximum take off weight of 25 kg and is powered by an electric motor to reduce engine exhaust and concerns about carburetor icing. It carries instrumentation to make measurements of broadband up- and downwelling shortwave and longwave radiation, aerosol particle size distribution, atmospheric temperature, relative humidity and pressure and to collect video of flights for subsequent analysis of atmospheric conditions during flight. In order to make the shortwave radiation measurements, care was taken to carefully position a high-quality compact inertial measurement unit (IMU and characterize the attitude of the aircraft and it's orientation to the upward looking radiation sensor. Using measurements from both of these sensors, a correction is applied to the raw radiometer measurements to correct for aircraft attitude and sensor tilt relative to the sun. The data acquisition system was designed from scratch based on a set of key driving requirements to accommodate the variety of sensors deployed. Initial test flights completed in Colorado provide promising results with measurements from the radiation sensors agreeing with those from a nearby surface site. Additionally, estimates of surface albedo from onboard sensors were consistent with local surface conditions, including melting snow and bright runway surface. Aerosol size distributions collected are internally consistent and have previously been shown to agree well with larger, surface-based instrumentation. Finally the atmospheric state measurements evolve as expected, with the near-surface atmosphere warming over time as the day goes on, and the atmospheric relative humidity decreasing with increased temperature. No directional bias on measured

  14. The Pilatus Unmanned Aircraft System for Lower Atmospheric Research

    Energy Technology Data Exchange (ETDEWEB)

    de Boer, Gijs; Palo, Scott; Agrow, Brian; LoDolce, Gabriel; Mack, James; Gao, Ru-Shan; Telg, Hagen; Trussell, Cameron; Fromm, Joshua; Long, Charles N.; Bland, Geoff I.; Maslanik, James; Schmid, Beat; Hock, Terry

    2016-04-28

    This paper presents the University of Colorado Pilatus unmanned research aircraft, assembled to provide measurements of aerosols, radiation and thermodynamics in the lower troposphere. This aircraft has a wingspan of 3.2 meters and a maximum take off weight of 25 kg and is pow-ered by an electric motor to reduce engine exhaust and concerns about carburetor icing. It carries instrumentation to make measurements of broadband up- and downwelling shortwave and longwave radiation, aerosol particle size distribution, atmospheric temperature, relative humidity and pressure and to collect video of flights for subsequent analysis of atmospheric conditions during flight. In order to make the shortwave radiation measurements, care was taken to carefully position a high-quality compact inertial measurement unit (IMU) and characterize the orientation offset between it and the upward looking radiation sensor. Using measurements from both of these sensors, a cor-rection is applied to the raw measurements to correct for aircraft attitude and sensor tilt relative to he sun. The data acquisition system was designed from the ground up in order to accommodate the variety of sensors deployed. Initial test flights completed in Colorado provide promising results with measurements from the radiation sensors generally agreeing with those from a nearby surface site. Additionally, estimates of surface albedo from onboard sensors were consistent with local surface conditions, including melting snow and bright runway surface. Aerosol size distributions collected are internally consistent and have previously been shown to agree well with larger, surface-based instrumentation. Finally the atmospheric state measurements evolve as would be expected, with the near-surface atmosphere warming over time as the day goes on, and the atmospheric relative humidity decreasing with increased temperature. No directional bias on measured temperature, as might be expected due to uneven heating of the sensor

  15. Development of Ultra-Thin Polyethylene Balloons for High Altitude Research upto Mesosphere

    Science.gov (United States)

    Kumar, B. Suneel; Nagendra, N.; Ojha, D. K.; Peter, G. Stalin; Vasudevan, R.; Anand, D.; Kulkarni, P. M.; Reddy, V. Anmi; Rao, T. V.; Sreenivasan, S.

    Ever since its inception four decades back, Balloon Facility of Tata Institute of Fundamental Research (TIFR), Hyderabad has been functioning with the needs of its user scientists at its focus. During the early nineties, when the X-ray astronomy group at TIFR expressed the need for balloons capable of carrying the X-ray telescopes to altitudes up to 42 km, the balloon group initiated research and development work on indigenous balloon grade films in various thickness not only for the main experiment but also in parallel, took up the development of thin films in thickness range 5 to 6 μm for fabrication of sounding balloons required for probing the stratosphere up to 42 km as the regular 2000-gram rubber balloon ascents could not reach altitudes higher than 38 km. By the year 1999, total indigenization of sounding balloon manufacture was accomplished. The work on balloon grade ultra-thin polyethylene film in thickness range 2.8 to 3.8 μm for fabrication of balloons capable of penetrating mesosphere to meet the needs of user scientists working in the area of atmospheric dynamics commenced in 2011. Pursuant to the successful trials with 61,000-m3 balloon made of 3.8-μm Antrix film reaching stratopause (48 km) for the first time in the history of balloon facility in the year 2012, fine tuning of launch parameters like percentage free lift was carried out to take the same volume balloons to higher mesospheric altitudes. Three successful flights with a total suspended load of 10 kg using 61,000-m3 balloons were carried out in the month of January 2014 and all the three balloons crossed into the mesosphere reaching altitudes of over 51 km. All the balloons flown so far are closed system with no escape ducts. Balloon fabrication, development of launch hardware, flight control instruments and launch technique for these mesospheric balloon flights are discussed in this paper.

  16. DLR HABLEG- High Altitude Balloon Launched Experimental Glider

    Science.gov (United States)

    Wlach, S.; Schwarzbauch, M.; Laiacker, M.

    2015-09-01

    The group Flying Robots at the DLR Institute of Robotics and Mechatronics in Oberpfaffenhofen conducts research on solar powered high altitude aircrafts. Due to the high altitude and the almost infinite mission duration, these platforms are also denoted as High Altitude Pseudo-Satellites (HAPS). This paper highlights some aspects of the design, building, integration and testing of a flying experimental platform for high altitudes. This unmanned aircraft, with a wingspan of 3 m and a mass of less than 10 kg, is meant to be launched as a glider from a high altitude balloon in 20 km altitude and shall investigate technologies for future large HAPS platforms. The aerodynamic requirements for high altitude flight included the development of a launch method allowing for a safe transition to horizontal flight from free-fall with low control authority. Due to the harsh environmental conditions in the stratosphere, the integration of electronic components in the airframe is a major effort. For regulatory reasons a reliable and situation dependent flight termination system had to be implemented. In May 2015 a flight campaign was conducted. The mission was a full success demonstrating that stratospheric research flights are feasible with rather small aircrafts.

  17. Development of Techniques for the In Situ Observation of OH and HO2 for Studies of the Impact of High-Altitude Supersonic Aircraft on the Stratosphere

    Science.gov (United States)

    Anderson, James G.

    1994-01-01

    This three-year project supported the construction, calibration, and deployment of a new instrument to measure the OH and HO2 radicals on the NASA ER-2 aircraft. The instrument has met and exceeded all of its design goals. The instrumentation represents a true quantum leap in performance over that achieved in previous HO(x) instruments built in our group. Sensitivity for OH was enhanced by over two orders of magnitude as the weight fell from approximately 1500 to less than 200 Kg. Reliability has been very high: HO(x) data are available for all flights during the first operational mission, the Stratospheric Photochemistry, Aerosols, and Dynamics Expedition (SPADE). The results of that experiment have been reported in the scientific literature and at conferences. Additionally, measurements of H2O and O3 were made and have been reported in the scientific literature. The measurements demonstrate the important role that OH and HO2 play in determining the concentration of ozone in the lower stratosphere. During the SPADE campaign, the measurements demonstrate that the catalytic removal is dominated by processes involving the odd-hydrogen and halogen radical extremely important constraint for photochemical models that are being used to assess the potential deleterious effects of super-sonic aircraft effluent on the burden of stratospheric ozone. A list of the papers that came from this research are included, along with a copy of the paper, 'Aircraft-borne, laser-induced fluorescence instrument for the in situ detection of hydroxyl and hydroperoxyl radicals'.

  18. Current and Future Research in Active Control of Lightweight, Flexible Structures Using the X-56 Aircraft

    Science.gov (United States)

    Ryan, John J.; Bosworth, John T.; Burken, John J.; Suh, Peter M.

    2014-01-01

    The X-56 Multi-Utility Technology Testbed aircraft system is a versatile experimental research flight platform. The system was primarily designed to investigate active control of lightweight flexible structures, but is reconfigurable and capable of hosting a wide breadth of research. Current research includes flight experimentation of a Lockheed Martin designed active control flutter suppression system. Future research plans continue experimentation with alternative control systems, explore the use of novel sensor systems, and experiments with the use of novel control effectors. This paper describes the aircraft system, current research efforts designed around the system, and future planned research efforts that will be hosted on the aircraft system.

  19. High Altitude Long Endurance Remotely Operated Aircraft - National Airspace System Integration - Simulation IPT: Detailed Airspace Operations Simulation Plan. Version 1.0

    Science.gov (United States)

    2004-01-01

    The primary goal of Access 5 is to allow safe, reliable and routine operations of High Altitude-Long Endurance Remotely Operated Aircraft (HALE ROAs) within the National Airspace System (NAS). Step 1 of Access 5 addresses the policies, procedures, technologies and implementation issues of introducing such operations into the NAS above pressure altitude 40,000 ft (Flight Level 400 or FL400). Routine HALE ROA activity within the NAS represents a potentially significant change to the tasks and concerns of NAS users, service providers and other stakeholders. Due to the complexity of the NAS, and the importance of maintaining current high levels of safety in the NAS, any significant changes must be thoroughly evaluated prior to implementation. The Access 5 community has been tasked with performing this detailed evaluation of routine HALE-ROA activities in the NAS, and providing to key NAS stakeholders a set of recommended policies and procedures to achieve this goal. Extensive simulation, in concert with a directed flight demonstration program are intended to provide the required supporting evidence that these recommendations are based on sound methods and offer a clear roadmap to achieving safe, reliable and routine HALE ROA operations in the NAS. Through coordination with NAS service providers and policy makers, and with significant input from HALE-ROA manufacturers, operators and pilots, this document presents the detailed simulation plan for Step 1 of Access 5. A brief background of the Access 5 project will be presented with focus on Steps 1 and 2, concerning HALE-ROA operations above FL400 and FL180 respectively. An overview of project management structure follows with particular emphasis on the role of the Simulation IPT and its relationships to other project entities. This discussion will include a description of work packages assigned to the Simulation IPT, and present the specific goals to be achieved for each simulation work package, along with the associated

  20. Aircraft Engine Noise Research and Testing at the NASA Glenn Research Center

    Science.gov (United States)

    Elliott, Dave

    2015-01-01

    The presentation will begin with a brief introduction to the NASA Glenn Research Center as well as an overview of how aircraft engine noise research fits within the organization. Some of the NASA programs and projects with noise content will be covered along with the associated goals of aircraft noise reduction. Topics covered within the noise research being presented will include noise prediction versus experimental results, along with engine fan, jet, and core noise. Details of the acoustic research conducted at NASA Glenn will include the test facilities available, recent test hardware, and data acquisition and analysis methods. Lastly some of the actual noise reduction methods investigated along with their results will be shown.

  1. Development of ultra-thin polyethylene balloons for high altitude research upto mesosphere

    CERN Document Server

    Kumar, B Suneel; Ojha, D K; Peter, G Stalin; Vasudevan, R; Anand, D; Kulkarni, P M; Reddy, V Anmi; Rao, T V; Sreenivasan, S

    2014-01-01

    Ever since its inception four decades back, Balloon Facility of Tata Institute of Fundamental Research (TIFR), Hyderabad has been functioning with the needs of its user scientists at its focus. During the early nineties, when the X-ray astronomy group at TIFR expressed the need for balloons capable of carrying the X-ray telescopes to altitudes up to 42 km, the balloon group initiated research and development work on indigenous balloon grade films in various thickness not only for the main experiment but also in parallel, took up the development of thin films in thickness range 5 to 6 microns for fabrication of sounding balloons required for probing the stratosphere up to 42 km as the regular 2000 grams rubber balloon ascents could not reach altitudes higher than 38 km. By the year 1999, total indigenisation of sounding balloon manufacture was accomplished. The work on balloon grade ultra-thin polyethylene film in thickness range 2.8 to 3.8 microns for fabrication of balloons capable of penetrating mesosphere ...

  2. Research on Data Distribution Service for Aircraft Collaborative Design System

    Directory of Open Access Journals (Sweden)

    Huaxing Bian

    2014-01-01

    Full Text Available Aircraft designing is a complex, multi-disciplinary process, while the applications are separated from each other due to their particular design and analysis tools. The separated applications are unable to meet the collaborative designing requirements. One of the fundamental problems in Aircraft Collaborative Design System is that how to make each subsystem collaborate. The known solutions, using Existing middlewares to unify data formats, are not reliable due to the tightly coupled architecture, poor portability and reusability, large update latency, etc. To solve this problem, the paper propose that apply DDS into Aircraft Collaborative Design System, and give the solution that how to use open source projects OpenDDS in Aircraft Collaborative Design System.

  3. Prototype-Technology Evaluator and Research Aircraft (PTERA) Flight Test Assessment Project

    Data.gov (United States)

    National Aeronautics and Space Administration — The Area-I team has developed and fabricated the unmanned Prototype-Technology Evaluation and Research Aircraft or PTERA ("ptera" being Greek for wing, or...

  4. Aircraft noise effects on sleep: Mechanisms, mitigation and research needs

    Directory of Open Access Journals (Sweden)

    Mathias Basner

    2010-01-01

    Full Text Available There is an ample number of laboratory and field studies which provide sufficient evidence that aircraft noise disturbs sleep and, depending on traffic volume and noise levels, may impair behavior and well-being during the day. Although clinical sleep disorders have been shown to be associated with increased risk of cardiovascular diseases, only little is known about the long-term effects of aircraft noise disturbed sleep on health. National and international laws and guidelines try to limit aircraft noise exposure facilitating active and passive noise control to prevent relevant sleep disturbances and its consequences. Adopting the harmonized indicator of the European Union Directive 2002/49/EC, the WHO Night Noise Guideline for Europe (NNG defines four Lnight , outside ranges associated with different risk levels of sleep disturbance and other health effects ( 55 dBA. Although traffic patterns differing in number and noise levels of events that lead to varying degrees of sleep disturbance may result in the same Lnight , simulations of nights with up to 200 aircraft noise events per night nicely corroborate expert opinion guidelines formulated in WHO′s NNG. In the future, large scale field studies on the effects of nocturnal (aircraft noise on sleep are needed. They should involve representative samples of the population including vulnerable groups like children and chronically ill subjects. Optimally, these studies are prospective in nature and examine the long-term consequences of noise-induced sleep disturbances. Furthermore, epidemiological case-control studies on the association of nocturnal (aircraft noise exposure and cardiovascular disease are needed. Despite the existing gaps in knowledge on long-term health effects, sufficient data are available for defining limit values, guidelines and protection concepts, which should be updated with the availability of new data.

  5. Research of low boom and low drag supersonic aircraft design

    Institute of Scientific and Technical Information of China (English)

    Feng Xiaoqiang; Li Zhanke; Song Bifeng

    2014-01-01

    Sonic boom reduction will be an issue of utmost importance in future supersonic trans-port, due to strong regulations on acoustic nuisance. The paper describes a new multi-objective optimization method for supersonic aircraft design. The method is developed by coupling Seebass-George-Darden (SGD) inverse design method and multi-objective genetic algorithm. Based on the method, different codes are developed. Using a computational architecture, a concep-tual supersonic aircraft design environment (CSADE) is constructed. The architecture of CSADE includes inner optimization level and out optimization level. The low boom configuration is gener-ated in inner optimization level by matching the target equivalent area distribution and actual equivalent area distribution. And low boom/low drag configuration is generated in outer optimiza-tion level by using NSGA-II multi-objective genetic algorithm to optimize the control parameters of SGD method and aircraft shape. Two objective functions, low sonic boom and low wave drag, are considered in CSADE. Physically reasonable Pareto solutions are obtained from the present optimization. Some supersonic aircraft configurations are selected from Pareto front and the optimization results indicate that the swept forward wing configuration has benefits in both sonic boom reduction and wave drag reduction. The results are validated by using computational fluid dynamics (CFD) analysis.

  6. Design of Prototype-Technology Evaluator and Research Aircraft (PTERA) Configuration for Loss of Control Flight Research Project

    Data.gov (United States)

    National Aeronautics and Space Administration — The Area-I team has developed and fabricated the unmanned Prototype-Technology Evaluation and Research Aircraft or PTERA ("ptera" being Greek for wing, or...

  7. Conceptual design and RCS performance research of shipborne early warning aircraft

    Institute of Scientific and Technical Information of China (English)

    Kuizhi Yue; Yong Gao; Guanxiong Li; Dazhao Yu

    2014-01-01

    In order to improve the survivability of the aircraft, conceptual design and radar cross section (RCS) performance research are done. The CATIA software is used to design the 3D digital model of the shipborne early warning aircraft, and some measures are taken to reduce the RCS characteristics of the early warning aircraft at the same time. Based on the physical optics method and the equivalent electromagnetic flow method, the aircraft’s RCS characteristics and strength distribution charac-teristics are simulated numerical y, and compared with the foreign advanced shipborne early warning aircraft. The simulation results show that under the X radar band, when the incident wave pitching angle is 0◦, compared with the foreign advanced shipborne early warning aircraft, the forward RCS average value of the concep-tual shipborne early warning aircraft is reduced to 24.49%, the lateral RCS average value is reduced to 5.04%, and the backward RCS average value is reduced to 39.26%. The research results of this paper are expected to provide theoretical basis and technical support for the conceptual design and the stealth design of the shipborne early warning aircraft.

  8. High-Altitude Balloon Launches for Effective Education, Inspiration and Research

    Science.gov (United States)

    Voss, H. D.; Dailey, J.; Patterson, D.; Krueger, J.

    2006-12-01

    Over a three-year period the Taylor University Science Research Training Program (SRTP) has successfully launched and recovered 33 sophisticated payloads to altitudes between 20-33 km (100% success with rapid recovery). All of the payloads included two GPS tracking systems, cameras and monitors, a 110 kbit down link, and uplink command capability for educational experiments (K-12 and undergrad) and nanosatellite subsystem testing. Launches were conducted both day and night, with multiple balloons, with up to 10 experiment boxes, and under varying weather and upper atmospheric conditions. The many launches in a short period of time allowed the payload bus design to evolve toward increased performance, reliability, standardization, simplicity, and modularity for low-cost launch services. The current design uses a Zigbee wireless connection (50 kbaud rate) for each of the payload experiment boxes for rapid assembly and checkout with a common interface board for gathering analog and digital data and for commanding. Common data from each box is processed and displayed using modular LabView software. The use of balloons for active research (ozone, aerosols, cosmic rays. UV, IR, remote sensing, energy, propulsion) significantly invigorates and motivates student development, drives team schedule, uncovers unexpected problems, permits end-to-end closure, and forces calibration and validation of real data. The SRTP has helped to spin off a student company called StratoStar Systems for providing an affordable low-cost balloon launch service capability, insurance plan, and other technical assistance for scientific, industrial and STEM educational use.

  9. ALADINA - an unmanned research aircraft for observing vertical and horizontal distributions of ultrafine particles within the atmospheric boundary layer

    Science.gov (United States)

    Altstädter, B.; Platis, A.; Wehner, B.; Scholtz, A.; Wildmann, N.; Hermann, M.; Käthner, R.; Baars, H.; Bange, J.; Lampert, A.

    2015-04-01

    This paper presents the unmanned research aircraft Carolo P360 "ALADINA" (Application of Light-weight Aircraft for Detecting IN situ Aerosol) for investigating the horizontal and vertical distribution of ultrafine particles in the atmospheric boundary layer (ABL). It has a wingspan of 3.6 m, a maximum take-off weight of 25 kg and is equipped with aerosol instrumentation and meteorological sensors. A first application of the system, together with the unmanned research aircraft MASC (Multi-Purpose Airborne Carrier) of the Eberhard Karls University of Tübingen (EKUT), is described. As small payload for ALADINA, two condensation particle counters (CPC) and one optical particle counter (OPC) were miniaturised by re-arranging the vital parts and composing them in a space-saving way in the front compartment of the airframe. The CPCs are improved concerning the lower detection threshold and the response time to less than 1.3 s. Each system was characterised in the laboratory and calibrated with test aerosols. The CPCs are operated in this study with two different lower detection threshold diameters of 11 and 18 nm. The amount of ultrafine particles, which is an indicator for new particle formation, is derived from the difference in number concentrations of the two CPCs (ΔN). Turbulence and thermodynamic structure of the boundary layer are described by measurements of fast meteorological sensors that are mounted at the aircraft nose. A first demonstration of ALADINA and a feasibility study were conducted in Melpitz near Leipzig, Germany, at the Global Atmosphere Watch (GAW) station of the Leibniz Institute for Tropospheric Research (TROPOS) on 2 days in October 2013. There, various ground-based instruments are installed for long-term atmospheric monitoring. The ground-based infrastructure provides valuable additional background information to embed the flights in the continuous atmospheric context and is used for validation of the airborne results. The development of the

  10. Research on the Key Technology of Large Scale Mapping from Low Altitude Photogrammetry

    Science.gov (United States)

    Bo-Yi, Wu; Ning, Zhang; Guo-Zhong, Su

    2016-06-01

    Based on the theoretic analysis of the accuracy in large scale photogrammetric mapping, some defects in traditional procedure were discussed. A set of key technologies dedicate to accuracy improvement in low altitude photogrammetry were analyzed in detail, namely the utilization of wide angle camera and low altitude flight, enhancement in image matching, predesigned layout of Ground Control Points (GCPs) in field survey, optimization of adjustment model and improvement in map processing. Besides, a low altitude aerial unmanned airship system was established. Finally, successful implementation in 1:500 topographic mapping project in built-up areas of 30 counties in Shanxi Province proves the practicability and effectiveness of the proposed approaches.

  11. RESEARCH ON THE KEY TECHNOLOGY OF LARGE SCALE MAPPING FROM LOW ALTITUDE PHOTOGRAMMETRY

    OpenAIRE

    Bo-Yi, Wu; Ning, Zhang; Guo-Zhong, Su

    2016-01-01

    Based on the theoretic analysis of the accuracy in large scale photogrammetric mapping, some defects in traditional procedure were discussed. A set of key technologies dedicate to accuracy improvement in low altitude photogrammetry were analyzed in detail, namely the utilization of wide angle camera and low altitude flight, enhancement in image matching, predesigned layout of Ground Control Points (GCPs) in field survey, optimization of adjustment model and improvement in map processing. Besi...

  12. Methane and nitrous oxide measurements onboard the UK Atmospheric Research Aircraft using quantum cascade laser spectrometry (QCL)

    Science.gov (United States)

    Muller, J. B.; O'Shea, S.; Dorsey, J.; Bauguitte, S.; Cain, M.; Allen, G.; Percival, C. J.; Gallagher, M. W.

    2012-12-01

    A Aerodyne Research© Mini-Quantum Cascade Laser (QCL) spectrometer was installed on the UK Facility of Airborne Atmospheric Measurements (FAAM) BAe-146 research aircraft and employed during summer 2012. Methane (CH4) and nitrous oxide (N2O) concentrations were measured within the Arctic Circle as part of the MAMM project (Methane and other greenhouse gases in the Arctic - Measurements, process studies and Modelling) as well as around the UK as part of the ClearfLo project (Clean Air for London). A range of missions were flown, including deep vertical profiles up to the stratosphere, providing concentration profiles of CH4 and N2O, as well as low altitude level runs exploring near surface diffuse emission sources such as the wetlands in Arctic Lapland and point emissions sources such as gas platforms off the UK coast. Significant pollution plumes were observed both in the Arctic and around the UK with elevated CH4 concentrations, as well as enhanced CO, O3 and aerosol levels. The NAME Lagrangian particle dispersion model will be used to investigate the origins of these CH4 plumes to identify the locations of the emissions sources. The first set of flights using QCL on the FAAM research aircraft have been successful and regular in-flight calibrations (high/low span) and target concentrations were used to determine instrument accuracy and precision. Additional data quality control checks could be made by comparison with an onboard Los Gatos Fast Greenhouse Gas Analyser (FGGA) for CO2 and CH4 and provide the basis for further instrument development and implementation for future Arctic MAMM flights during spring and summer 2013.

  13. Amphibious Aircraft

    Data.gov (United States)

    National Aeronautics and Space Administration — A brief self composed research article on Amphibious Aircrafts discussing their use, origin and modern day applications along with their advantages and...

  14. Subsonic Ultra Green Aircraft Research Phase II: N+4 Advanced Concept Development

    Science.gov (United States)

    Bradley, Marty K.; Droney, Christopher K.

    2012-01-01

    This final report documents the work of the Boeing Subsonic Ultra Green Aircraft Research (SUGAR) team on Task 1 of the Phase II effort. The team consisted of Boeing Research and Technology, Boeing Commercial Airplanes, General Electric, and Georgia Tech. Using a quantitative workshop process, the following technologies, appropriate to aircraft operational in the N+4 2040 timeframe, were identified: Liquefied Natural Gas (LNG), Hydrogen, fuel cell hybrids, battery electric hybrids, Low Energy Nuclear (LENR), boundary layer ingestion propulsion (BLI), unducted fans and advanced propellers, and combinations. Technology development plans were developed.

  15. Satellite communications provisions on NASA Ames instrumented aircraft platforms for Earth science research/applications

    Science.gov (United States)

    Shameson, L.; Brass, J. A.; Hanratty, J. J.; Roberts, A. C.; Wegener, S. S.

    1995-01-01

    Earth science activities at NASA Ames are research in atmospheric and ecosystem science, development of remote sensing and in situ sampling instruments, and their integration into scientific research platform aircraft. The use of satellite communications can greatly extend the capability of these agency research platform aircraft. Current projects and plans involve satellite links on the Perseus UAV and the ER-2 via TDRSS and a proposed experiment on the NASA Advanced Communications Technology Satellite. Provisions for data links on the Perseus research platform, via TDRSS S-band multiple access service, have been developed and are being tested. Test flights at Dryden are planned to demonstrate successful end-to-end data transfer. A Unisys Corp. airborne satcom STARLink system is being integrated into an Ames ER-2 aircraft. This equipment will support multiple data rates up to 43 Mb/s each via the TDRS S Ku-band single access service. The first flight mission for this high-rate link is planned for August 1995. Ames and JPL have proposed an ACTS experiment to use real-time satellite communications to improve wildfire research campaigns. Researchers and fire management teams making use of instrumented aircraft platforms at a prescribed burn site will be able to communicate with experts at Ames, the U.S. Forest Service, and emergency response agencies.

  16. Rotary Balance Wind Tunnel Testing for the FASER Flight Research Aircraft

    Science.gov (United States)

    Denham, Casey; Owens, D. Bruce

    2016-01-01

    Flight dynamics research was conducted to collect and analyze rotary balance wind tunnel test data in order to improve the aerodynamic simulation and modeling of a low-cost small unmanned aircraft called FASER (Free-flying Aircraft for Sub-scale Experimental Research). The impetus for using FASER was to provide risk and cost reduction for flight testing of more expensive aircraft and assist in the improvement of wind tunnel and flight test techniques, and control laws. The FASER research aircraft has the benefit of allowing wind tunnel and flight tests to be conducted on the same model, improving correlation between wind tunnel, flight, and simulation data. Prior wind tunnel tests include a static force and moment test, including power effects, and a roll and yaw damping forced oscillation test. Rotary balance testing allows for the calculation of aircraft rotary derivatives and the prediction of steady-state spins. The rotary balance wind tunnel test was conducted in the NASA Langley Research Center (LaRC) 20-Foot Vertical Spin Tunnel (VST). Rotary balance testing includes runs for a set of given angular rotation rates at a range of angles of attack and sideslip angles in order to fully characterize the aircraft rotary dynamics. Tests were performed at angles of attack from 0 to 50 degrees, sideslip angles of -5 to 10 degrees, and non-dimensional spin rates from -0.5 to 0.5. The effects of pro-spin elevator and rudder deflection and pro- and anti-spin elevator, rudder, and aileron deflection were examined. The data are presented to illustrate the functional dependence of the forces and moments on angle of attack, sideslip angle, and angular rate for the rotary contributions to the forces and moments. Further investigation is necessary to fully characterize the control effectors. The data were also used with a steady state spin prediction tool that did not predict an equilibrium spin mode.

  17. Human biological research since 2006 at the Christian-Albrechts-University in Kiel--aging, chronobiology, and high altitude adaptation.

    Science.gov (United States)

    Dittmar, Manuela

    2014-01-01

    This article reviews the research at the Department of Human Biology at the Christian-Albrechts-University in Kiel since 2006. The research focuses on the investigation of recent human populations with respect to aging, chronobiology, and adaptation to high altitude. The research areas are outlined presenting findings, ongoing projects and future directions. Aging research examines biological changes in humans considering that aging is a multidimensional process. Changes in body composition, resting energy metabolism, oxidative stress, and sleep have been examined. The applicability of specific research methods to older people has been tested. Chronobiological research concentrates on investigating circadian rhythms of humans. The emphasis lies on the sleep-wake rhythm, body temperature rhythms, hormonal rhythms (cortisol and melatonin) and the circadian expression of so-called clock genes which are involved in the generation of circadian rhythms. Association studies examine the relationship between defined chronobiological phenotypes and clock gene polymorphisms. Genetic aspects are as well investigated within the third research area on the adaptation of native populations to life at high altitude in the South American Andes. Both candidate gene analysis and epigenetic parameters are investigated. Future research will concentrate on the aging of the circadian system. PMID:24818445

  18. Calibration and Quality Assurance of Flux Observations from a Small Research Aircraft

    NARCIS (Netherlands)

    Vellinga, O.S.; Dobosy, R.J.; Dumas, E.J.; Beniamino, G.; Elbers, J.A.; Hutjes, R.W.A.

    2013-01-01

    Small environmental research aircraft (ERA) are becoming more common for detailed studies of air–surface interactions. The Sky Arrow 650 ERA, used by multiple groups, is designed to minimize the complexity of high-precision airborne turbulent wind measurement. Its relative wind probe, of a nine-port

  19. CV-990 Landing Systems Research Aircraft (LSRA) during final Space Shuttle tire test

    Science.gov (United States)

    1995-01-01

    A Convair 990 (CV-990) was used as a Landing Systems Research Aircraft (LSRA) at NASA's Dryden Flight Research Center, Edwards, California, to test space shuttle landing gear and braking systems as part of NASA's effort to upgrade and improve space shuttle capabilities. The first flight at Dryden of the CV-990 with shuttle test components occurred in April 1993, and tests continued into August 1995, when this photo shows a test of the shuttle tires. The purpose of this series of tests was to determine the performance parameters and failure limits of the tires. This particular landing was on the dry lakebed at Edwards, but other tests occurred on the main runway there. The CV-990, built in 1962 by the Convair Division of General Dynamics Corp., Ft. Worth, Texas, served as a research aircraft at Ames Research Center, Moffett Field, California, before it came to Dryden.

  20. Practical Application of a Subscale Transport Aircraft for Flight Research in Control Upset and Failure Conditions

    Science.gov (United States)

    Cunningham, Kevin; Foster, John V.; Morelli, Eugene A.; Murch, Austin M.

    2008-01-01

    Over the past decade, the goal of reducing the fatal accident rate of large transport aircraft has resulted in research aimed at the problem of aircraft loss-of-control. Starting in 1999, the NASA Aviation Safety Program initiated research that included vehicle dynamics modeling, system health monitoring, and reconfigurable control systems focused on flight regimes beyond the normal flight envelope. In recent years, there has been an increased emphasis on adaptive control technologies for recovery from control upsets or failures including damage scenarios. As part of these efforts, NASA has developed the Airborne Subscale Transport Aircraft Research (AirSTAR) flight facility to allow flight research and validation, and system testing for flight regimes that are considered too risky for full-scale manned transport airplane testing. The AirSTAR facility utilizes dynamically-scaled vehicles that enable the application of subscale flight test results to full scale vehicles. This paper describes the modeling and simulation approach used for AirSTAR vehicles that supports the goals of efficient, low-cost and safe flight research in abnormal flight conditions. Modeling of aerodynamics, controls, and propulsion will be discussed as well as the application of simulation to flight control system development, test planning, risk mitigation, and flight research.

  1. Water Metabolism and Fluid Compartment Volumes in Humans at Altitude. A Compendium of Research (1914 - 1996)

    Science.gov (United States)

    Chou, J. L.; Stad, N. J.; Gay, E.; West, G. I.; Barnes, P. R.; Greenleaf, J. E.

    1997-01-01

    This compendium includes abstracts and synopses of clinical observations and of more basic studies involving physiological mechanisms concerning interaction of water metabolism and fluid compartment volumes in humans during altitude exposure. If the author's abstract or summary was appropriate, it was included. In other cases a more detailed synopsis of the paper was prepared under the subheadings Purpose, Methods, Results, and Conclusions. Author and subject indices are provided, plus an additional selected bibliography of related work of those papers received after the volume was being prepared for publication. This volume includes material published from 1914 through 1995.

  2. Federal Interagency Committee on Aviation Noise (FICAN) Position on Research into Effects of Aircraft Noise on Classroom Learning.

    Science.gov (United States)

    2000

    This symposium report presents a summary of research on the affect of aircraft noise on the classroom environment revealing that aircraft noise can interfere with learning in the following areas: reading, motivation, language and speech acquisition, and memory. The strongest findings are in the area of reading, where more than 20 studies have…

  3. Production-teaching-research of a Commercial Aircraft Corporation in the Chinese Industry Chain

    Institute of Scientific and Technical Information of China (English)

    CHEN Lin; WANG Shuang-yuan; WEI Lin-wan

    2012-01-01

    For the future development of a commercial aircraft corporation, this paper focused on the research and technological innovation model in an industrial chain and explored how to promote the sustainable development of technological innovation on the basis of the Chinese aviation industry. It puts forward several ways to reinforce cooperation, such as strengthening policies and regulations, government's support for research cooperations, accelerating construction of the production-teaching-research oriented public technology platform and service system, and firming the industry awareness of universities and research institutes, and so on.

  4. Current Research in Aircraft Tire Design and Performance

    Science.gov (United States)

    Tanner, J. A.; Mccarthy, J. L.; Clark, S. K.

    1981-01-01

    A review of the tire research programs which address the various needs identified by landing gear designers and airplane users is presented. The experimental programs are designed to increase tire tread lifetimes, relate static and dynamic tire properties, establish the tire hydroplaning spin up speed, study gear response to tire failures, and define tire temperature profiles during taxi, braking, and cornering operations. The analytical programs are aimed at providing insights into the mechanisms of heat generation in rolling tires and developing the tools necessary to streamline the tire design process and to aid in the analysis of landing gear problems.

  5. Concept to Reality: Contributions of the Langley Research Center to US Civil Aircraft of the 1990s

    Science.gov (United States)

    Chambers, Joseph R.

    2003-01-01

    This document is intended to be a companion to NASA SP-2000-4519, 'Partners in Freedom: Contributions of the Langley Research Center to U.S. Military Aircraft of the 1990s'. Material included in the combined set of volumes provides informative and significant examples of the impact of Langley's research on U.S. civil and military aircraft of the 1990s. This volume, 'Concept to Reality: Contributions of the NASA Langley Research Center to U.S. Civil Aircraft of the 1990s', highlights significant Langley contributions to safety, cruise performance, takeoff and landing capabilities, structural integrity, crashworthiness, flight deck technologies, pilot-vehicle interfaces, flight characteristics, stall and spin behavior, computational design methods, and other challenging technical areas for civil aviation. The contents of this volume include descriptions of some of the more important applications of Langley research to current civil fixed-wing aircraft (rotary-wing aircraft are not included), including commercial airliners, business aircraft, and small personal-owner aircraft. In addition to discussions of specific aircraft applications, the document also covers contributions of Langley research to the operation of civil aircraft, which includes operating problems. This document is organized according to disciplinary technologies, for example, aerodynamics, structures, materials, and flight systems. Within each discussion, examples are cited where industry applied Langley technologies to specific aircraft that were in operational service during the 1990s and the early years of the new millennium. This document is intended to serve as a key reference for national policy makers, internal NASA policy makers, Congressional committees, the media, and the general public. Therefore, it has been written for a broad general audience and does not presume any significant technical expertise. An extensive bibliography is provided for technical specialists and others who desire a

  6. Gaseous ion-composition measurements in the young exhaust plume of jet aircraft at cruising altitudes. Implications for aerosols and gaseous sulfuric acid

    Energy Technology Data Exchange (ETDEWEB)

    Arnold, F.; Wohlfrom, K.H.; Klemm, M.; Schneider, J.; Gollinger, K. [Max-Planck-Inst. for Nuclear Physics, Heidelberg (Germany); Schumann, U.; Busen, R. [Deutsche Forschungsanstalt fuer Luft- und Raumfahrt e.V. (DLR), Wessling (Germany). Inst. fuer Physik der Atmosphaere

    1997-12-31

    Mass spectrometric measurements were made in the young exhaust plume of an Airbus (A310) at cruising altitudes at distances between 400 and 800 m behind the Airbus (averaged plume age: 3.4 sec). The measurements indicate that gaseous sulfuric acid (GSA) number densities were less than 1.3 x 10{sup 8} cm{sup -3} which is smaller than the expected total sulfuric acid. Hence the missing sulfuric acid must have been in the aerosol phase. These measurements also indicate a total aerosol surface area density A{sub T} {<=} 5.4 x 10{sup -5} cm{sup 2} per cm{sup 3} which is consistent with simultaneously measured soot and water contrail particles. However, homogeneous nucleation leading to (H{sub 2}SO{sub 4}){sub x}(H{sub 2}O){sub y}-clusters can not be ruled out. (author) 16 refs.

  7. Research and development of a portable radiation monitor for use at aviation altitude

    International Nuclear Information System (INIS)

    A portable radiation monitor for the application to in-flight measurement at high altitude is developed. The monitor named as Cosmic Radiation and Energetic Particle Analyzing System (CREPAS) is composed of a phoswich-type scintillator probe coupled with a high-speed data acquisition unit connected to a note computer via USB2.0 interface. The signal waveforms are analyzed on site for the discrimination of different radiation components. In order to examine the discrimination ability, the CREPAS was exposed to accelerated proton and helium beams at National Institute of Radiological Sciences-Heavy Ion Medical Accelerator in Chiba (NIRS-HIMAC) and the data were compared to those obtained at selected accelerator facilities (JAEA-FRS, Japan Atomic Energy Agency-Takasaki Ion Accelerators for Advanced Radiation Application (JAEA-TIARA) and Osaka Univ.-RCNP). As results, it was verified that this monitor can successfully detect heavy charged particles separately from neutrons. (author)

  8. Research and development of a portable radiation monitor for use at aviation altitude

    International Nuclear Information System (INIS)

    A portable radiation monitor named as ''CREPAS'' for the application to in-flight measurement at high altitude has been developed. The signal waveforms are analyzed on site for the discrimination of different radiation components obtained with a phoswich-type scintillation probe. In the present study, the discrimination ability of a new probe was tested for accelerated proton and helium-ion beams at National Institute of Radiological Sciences-Heavy Ion Medical Accelerator in Chiba (NIRS-HMAC) in comparison with the previous probe. It was verified so far that the new monitor can more successfully determine proton energies, separated from helium ions. The data were compared also to those for neutrons at JAEA-Takasaki Ion Accelerators for Advanced Radiation Application (TIARA). (author)

  9. Research of Two-media Underwater Reefs Depth Measurement Experiment Based on Low-altitude UAV

    Directory of Open Access Journals (Sweden)

    ZHOU Gaowei

    2015-05-01

    Full Text Available Based on the principle of two-media photogrammetry and with islands UAV images, a test of two-media photogrammetry is carried out. Firstly, there is an introduction of the principle of two-media photogrammetry. In the following step, the two-media photogrammetry requirements on the accuracy of the refractive index of sea water is discussed. Then, a new method for calculating the elevation correction coefficient is developed. The test procedure of two-media underwater reefs depth measurement based on low-altitude UAV images of underwater reefs surrounding the islands is designed. The test shows that aerial two-media photogrammetry is feasible in practical application, but relatively high requirements for aerial photography conditions.

  10. Polar Research with Unmanned Aircraft and Tethered Balloons

    Energy Technology Data Exchange (ETDEWEB)

    Ivey, M [Sandia National Laboratories; Petty, R [U.S. Department of Energy; Desilets, D [Sandia National Laboratories; Verlinde, J; Ellingson, R [Florida State University

    2014-01-24

    The Arctic is experiencing rapid climate change, with nearly double the rate of surface warming observed elsewhere on the planet. While various positive feedback mechanisms have been suggested, the reasons for Arctic amplification are not well understood, nor are the impacts to the global carbon cycle well quantified. Additionally, there are uncertainties associated with the complex interactions between Earth’s surface and the atmosphere. Elucidating the causes and consequences of Arctic warming is one of the many goals of the Climate and Environmental Sciences Division (CESD) of the U.S. Department of Energy’s (DOE) Biological and Environmental Research (BER) program, and is part of the larger CESD initiative to develop a robust predictive understanding of Earth’s climate system.

  11. Supersonic cruise research aircraft structural studies: Methods and results

    Science.gov (United States)

    Sobieszczanski-Sobieski, J.; Gross, D.; Kurtze, W.; Newsom, J.; Wrenn, G.; Greene, W.

    1981-01-01

    NASA Langley Research Center SCAR in-house structural studies are reviewed. In methods development, advances include a new system of integrated computer programs called ISSYS, progress in determining aerodynamic loads and aerodynamically induced structural loads (including those due to gusts), flutter optimization for composite and metal airframe configurations using refined and simplified mathematical models, and synthesis of active controls. Results given address several aspects of various SCR configurations. These results include flutter penalties on composite wing, flutter suppression using active controls, roll control effectiveness, wing tip ground clearance, tail size effect on flutter, engine weight and mass distribution influence on flutter, and strength and flutter optimization of new configurations. The ISSYS system of integrated programs performed well in all the applications illustrated by the results, the diversity of which attests to ISSYS' versatility.

  12. NASA rotor system research aircraft flight-test data report: Helicopter and compound configuration

    Science.gov (United States)

    Erickson, R. E.; Kufeld, R. M.; Cross, J. L.; Hodge, R. W.; Ericson, W. F.; Carter, R. D. G.

    1984-01-01

    The flight test activities of the Rotor System Research Aircraft (RSRA), NASA 740, from June 30, 1981 to August 5, 1982 are reported. Tests were conducted in both the helicopter and compound configurations. Compound tests reconfirmed the Sikorsky flight envelope except that main rotor blade bending loads reached endurance at a speed about 10 knots lower than previously. Wing incidence changes were made from 0 to 10 deg.

  13. Calibration of 3-D wind measurements on a single-engine research aircraft

    OpenAIRE

    Mallaun, C; Giez, A.; Baumann, R

    2015-01-01

    An innovative calibration method for the wind speed measurement using a boom-mounted Rosemount model 858 AJ air velocity probe is introduced. The method is demonstrated for a sensor system installed on a medium-size research aircraft which is used for measurements in the atmospheric boundary layer. The method encounters a series of coordinated flight manoeuvres to directly estimate the aerodynamic influences on the probe and to calculate the measurement uncertainties. The in...

  14. Fabrication methods for YF-12 wing panels for the Supersonic Cruise Aircraft Research Program

    Science.gov (United States)

    Hoffman, E. L.; Payne, L.; Carter, A. L.

    1975-01-01

    Advanced fabrication and joining processes for titanium and composite materials are being investigated by NASA to develop technology for the Supersonic Cruise Aircraft Research (SCAR) Program. With Lockheed-ADP as the prime contractor, full-scale structural panels are being designed and fabricated to replace an existing integrally stiffened shear panel on the upper wing surface of the NASA YF-12 aircraft. The program involves ground testing and Mach 3 flight testing of full-scale structural panels and laboratory testing of representative structural element specimens. Fabrication methods and test results for weldbrazed and Rohrbond titanium panels are discussed. The fabrication methods being developed for boron/aluminum, Borsic/aluminum, and graphite/polyimide panels are also presented.

  15. Dynamic structural aeroelastic stability testing of the XV-15 tilt rotor research aircraft

    Science.gov (United States)

    Schroers, L. G.

    1982-01-01

    For the past 20 years, a significant effort has been made to understand and predict the structural aeroelastic stability characteristics of the tilt rotor concept. Beginning with the rotor-pylon oscillation of the XV-3 aircraft, the problem was identified and then subjected to a series of theoretical studies, plus model and full-scale wind tunnel tests. From this data base, methods were developed to predict the structural aeroelastic stability characteristics of the XV-15 Tilt Rotor Research Aircraft. The predicted aeroelastic characteristics are examined in light of the major parameters effecting rotor-pylon-wing stability. Flight test techniques used to obtain XV-15 aeroelastic stability are described. Flight test results are summarized and compared to the predicted values. Wind tunnel results are compared to flight test results and correlated with predicted values.

  16. Unmanned Aircraft Systems in Remote Sensing and Scientific Research: Classification and Considerations of Use

    Directory of Open Access Journals (Sweden)

    Adam C. Watts

    2012-06-01

    Full Text Available Unmanned Aircraft Systems (UAS have evolved rapidly over the past decade driven primarily by military uses, and have begun finding application among civilian users for earth sensing reconnaissance and scientific data collection purposes. Among UAS, promising characteristics are long flight duration, improved mission safety, flight repeatability due to improving autopilots, and reduced operational costs when compared to manned aircraft. The potential advantages of an unmanned platform, however, depend on many factors, such as aircraft, sensor types, mission objectives, and the current UAS regulatory requirements for operations of the particular platform. The regulations concerning UAS operation are still in the early development stages and currently present significant barriers to entry for scientific users. In this article we describe a variety of platforms, as well as sensor capabilities, and identify advantages of each as relevant to the demands of users in the scientific research sector. We also briefly discuss the current state of regulations affecting UAS operations, with the purpose of informing the scientific community about this developing technology whose potential for revolutionizing natural science observations is similar to those transformations that GIS and GPS brought to the community two decades ago.

  17. Advancement of proprotor technology. Task 1: Design study summary. [aerodynamic concept of minimum size tilt proprotor research aircraft

    Science.gov (United States)

    1969-01-01

    A tilt-proprotor proof-of-concept aircraft design study has been conducted. The results are presented. The ojective of the contract is to advance the state of proprotor technology through design studies and full-scale wind-tunnel tests. The specific objective is to conduct preliminary design studies to define a minimum-size tilt-proprotor research aircraft that can perform proof-of-concept flight research. The aircraft that results from these studies is a twin-engine, high-wing aircraft with 25-foot, three-bladed tilt proprotors mounted on pylons at the wingtips. Each pylon houses a Pratt and Whitney PT6C-40 engine with a takeoff rating of 1150 horsepower. Empty weight is estimated at 6876 pounds. The normal gross weight is 9500 pounds, and the maximum gross weight is 12,400 pounds.

  18. Cost and schedule management on the quiet short-haul research aircraft project

    Science.gov (United States)

    Wilcox, D. E.; Patterakis, P.

    1979-01-01

    The Quiet Short-Haul Research Aircraft (QSRA) Project, one of the largest aeronautical programs undertaken by NASA to date, achieved a significant cost underrun. This is attributed to numerous factors, not the least of which were the contractual arrangement and the system of cost and schedule management employed by the contractor. This paper summarizes that system and the methods used for cost/performance measurement by the contractor and by the NASA project management. Recommendations are made for the use of some of these concepts in particular for future programs of a similar nature.

  19. Ultra-low altitude and low spraying technology research with UAV in paddy

    Science.gov (United States)

    Aerial application has characteristics of low-volume, small droplet, and possibility of drift. To control rice planthopper, leaf roller and blast, the research aimed at screening agrichemicals and determining the feasibility of using high concentration of conventional dosage for aerial application....

  20. An experimental and analytical method for approximate determination of the tilt rotor research aircraft rotor/wing download

    Science.gov (United States)

    Jordon, D. E.; Patterson, W.; Sandlin, D. R.

    1985-01-01

    The XV-15 Tilt Rotor Research Aircraft download phenomenon was analyzed. This phenomenon is a direct result of the two rotor wakes impinging on the wing upper surface when the aircraft is in the hover configuration. For this study the analysis proceeded along tow lines. First was a method whereby results from actual hover tests of the XV-15 aircraft were combined with drag coefficient results from wind tunnel tests of a wing that was representative of the aircraft wing. Second, an analytical method was used that modeled that airflow caused gy the two rotors. Formulas were developed in such a way that acomputer program could be used to calculate the axial velocities were then used in conjunction with the aforementioned wind tunnel drag coefficinet results to produce download values. An attempt was made to validate the analytical results by modeling a model rotor system for which direct download values were determinrd..

  1. Subsonic Ultra Green Aircraft Research: Phase 2. Volume 2; Hybrid Electric Design Exploration

    Science.gov (United States)

    Bradley, Marty K.; Droney, Christopher K.

    2015-01-01

    This report summarizes the hybrid electric concept design, analysis, and modeling work accomplished by the Boeing Subsonic Ultra Green Aircraft Research (SUGAR) team, consisting of Boeing Research and Technology, Boeing Commercial Airplanes, General Electric, and Georgia Tech.Performance and sizing tasks were conducted for hybrid electric versions of a conventional tube-and-wing aircraft and a hybrid wing body. The high wing Truss Braced Wing (TBW) SUGAR Volt was updated based on results from the TBW work (documented separately) and new engine performance models. Energy cost and acoustic analyses were conducted and technology roadmaps were updated for hybrid electric and battery technology. NOx emissions were calculated for landing and takeoff (LTO) and cruise. NPSS models were developed for hybrid electric components and tested using an integrated analysis of superconducting and non-superconducting hybrid electric engines. The hybrid electric SUGAR Volt was shown to produce significant emissions and fuel burn reductions beyond those achieved by the conventionally powered SUGAR High and was able to meet the NASA goals for fuel burn. Total energy utilization was not decreased but reduced energy cost can be achieved for some scenarios. The team was not able to identify a technology development path to meet NASA's noise goals

  2. Subsonic Ultra Green Aircraft Research. Phase II - Volume I; Truss Braced Wing Design Exploration

    Science.gov (United States)

    Bradley, Marty K.; Droney, Christopher K.; Allen, Timothy J.

    2015-01-01

    This report summarizes the Truss Braced Wing (TBW) work accomplished by the Boeing Subsonic Ultra Green Aircraft Research (SUGAR) team, consisting of Boeing Research and Technology, Boeing Commercial Airplanes, General Electric, Georgia Tech, Virginia Tech, NextGen Aeronautics, and Microcraft. A multi-disciplinary optimization (MDO) environment defined the geometry that was further refined for the updated SUGAR High TBW configuration. Airfoil shapes were tested in the NASA TCT facility, and an aeroelastic model was tested in the NASA TDT facility. Flutter suppression was successfully demonstrated using control laws derived from test system ID data and analysis models. Aeroelastic impacts for the TBW design are manageable and smaller than assumed in Phase I. Flutter analysis of TBW designs need to include pre-load and large displacement non-linear effects to obtain a reasonable match to test data. With the updated performance and sizing, fuel burn and energy use is reduced by 54% compared to the SUGAR Free current technology Baseline (Goal 60%). Use of the unducted fan version of the engine reduces fuel burn and energy by 56% compared to the Baseline. Technology development roadmaps were updated, and an airport compatibility analysis established feasibility of a folding wing aircraft at existing airports.

  3. Dynamically Scaled Modular Aircraft for Flight-Based Aviation Safety Research Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Area-I, Incorporated personnel have led the design, fabrication, and flight testing of twelve unmanned aircraft and one manned aircraft. Partnered with NASA and...

  4. Advances in Engineering Research : Volume 4, Environmental impacts of the future technologies of commercial aircraft

    OpenAIRE

    Khardi, Salah; KURNIAWAN, J

    2013-01-01

    Assessment of pollutant emissions (CO, HC and NOx) and fuel consumption of aircraft LTO cycles at Soekarno Hatta InternationalAirport is carried out for the first time. We stressed, by aircraft type, the large aircraft which represent the greatest contribution of pollutant emissions in and around this airport.Analysis is performed to precise theirmagnitude in relationship with fuel consumption. Distribution of aircraft pollutants for different operational modes (taxiing and takeoffs) is provi...

  5. Enabling Electric Propulsion for Flight - Hybrid Electric Aircraft Research at AFRC

    Science.gov (United States)

    Clarke, Sean; Lin, Yohan; Kloesel, Kurt; Ginn, Starr

    2014-01-01

    Advances in electric machine efficiency and energy storage capability are enabling a new alternative to traditional propulsion systems for aircraft. This has already begun with several small concept and demonstration vehicles, and NASA projects this technology will be essential to meet energy and emissions goals for commercial aviation in the next 30 years. In order to raise the Technology Readiness Level of electric propulsion systems, practical integration and performance challenges will need to be identified and studied in the near-term so that larger, more advanced electric propulsion system testbeds can be designed and built. Researchers at NASA Armstrong Flight Research Center are building up a suite of test articles for the development, integration, and validation of these systems in a real world environment.

  6. CV-990 Landing Systems Research Aircraft (LSRA) flight #145 drilling of shuttle tire using Tire Assa

    Science.gov (United States)

    1995-01-01

    Created from a 1/16th model of a German World War II tank, the TAV (Tire Assault Vehicle) was an important safety feature for the Convair 990 Landing System Research Aircraft, which tested space shuttle tires. It was imperative to know the extreme conditions the shuttle tires could tolerate at landing without putting the shuttle and its crew at risk. In addition, the CV990 was able to land repeatedly to test the tires. The TAV was built from a kit and modified into a radio controlled, video-equipped machine to drill holes in aircraft test tires that were in imminent danger of exploding because of one or more conditions: high air pressure, high temperatures, and cord wear. An exploding test tire releases energy equivalent to two and one-half sticks of dynamite and can cause severe injuries to anyone within 50 ft. of the explosion, as well as ear injury - possibly permanent hearing loss - to anyone within 100 ft. The degree of danger is also determined by the temperature pressure and cord wear of a test tire. The TAV was developed by David Carrott, a PRC employee under contract to NASA.

  7. 50 CFR 27.34 - Aircraft.

    Science.gov (United States)

    2010-10-01

    ... 50 Wildlife and Fisheries 6 2010-10-01 2010-10-01 false Aircraft. 27.34 Section 27.34 Wildlife and... WILDLIFE REFUGE SYSTEM PROHIBITED ACTS Disturbing Violations: With Vehicles § 27.34 Aircraft. The unauthorized operation of aircraft, including sail planes, and hang gliders, at altitudes resulting...

  8. In-situ measurements of chlorine activation, nitric acid redistribution and ozone depletion in the Antarctic lower vortex aboard the German research aircraft HALO during TACTS/ESMVal

    Science.gov (United States)

    Jurkat, Tina; Voigt, Christiane; Kaufmann, Stefan; Schlage, Romy; Gottschaldt, Klaus-Dirk; Ziereis, Helmut; Hoor, Peter; Bozem, Heiko; Müller, Stefan; Zahn, Andreas; Schlager, Hans; Oelhaf, Hermann; Sinnhuber, Björn-Martin; Dörnbrack, Andreas

    2016-04-01

    In-situ measurements of stratospheric chlorine compounds are rare and exhibit the potential to gain insight into small scale mixing processes where stratospheric air masses of different origin and history interact. In addition, the relationship with chemically stable trace gases helps to identify regions that have been modified by chemical processing on polar stratospheric clouds. To this end, in-situ measurements of ClONO2, HCl, HNO3, NOy, N2O and O3 have been performed in the Antarctic Polar Vortex in September 2012 aboard the German research aircraft HALO (High Altitude and Long Rang research aircraft) during the TACTS/ESMVal (Transport and Composition in the UTLS/Earth System Model Validation) mission. With take-off and landing in Capetown, HALO sampled vortex air with latitudes down to 65°S, at altitudes between 8 and 14.3 km and potential temperatures between 340 and 390 K. Before intering the vortex at 350 K potential temperature, HALO additionally sampled mid-latitude stratospheric air. The trace gas distributions at the edge of the Antarctic polar vortex show distinct signatures of processed upper stratospheric vortex air and chemically different lower stratospheric / upper tropospheric air. Diabatic descend of the vortex transports processed air into the lower stratosphere. Here small scale filaments of only a few kilometers extension form at the lower vortex boundary due to shear stress, ultimately leading to transport and irreversible mixing. Comparison of trace gas relationships with those at the beginning of the polar winter reveals substantial chlorine activation, ozone depletion de- and renitrification with high resolution. Furthermore, the measurements are compared to the chemistry climate models EMAC and supported by ECMWF analysis. Finally, we compare the Antarctic measurements with new measurements of ClONO2, HCl and HNO3 aboard HALO obtained during the Arctic mission POLSTRACC (POLar STratosphere in a Changing Climate) based in Kiruna (Sveden

  9. Laser Powered Aircraft Takes Flight

    Science.gov (United States)

    2003-01-01

    A team of NASA researchers from Marshall Space Flight Center (MSFC) and Dryden Flight Research center have proven that beamed light can be used to power an aircraft, a first-in-the-world accomplishment to the best of their knowledge. Using an experimental custom built radio-controlled model aircraft, the team has demonstrated a system that beams enough light energy from the ground to power the propeller of an aircraft and sustain it in flight. Special photovoltaic arrays on the plane, similar to solar cells, receive the light energy and convert it to electric current to drive the propeller motor. In a series of indoor flights this week at MSFC, a lightweight custom built laser beam was aimed at the airplane `s solar panels. The laser tracks the plane, maintaining power on its cells until the end of the flight when the laser is turned off and the airplane glides to a landing. The laser source demonstration represents the capability to beam more power to a plane so that it can reach higher altitudes and have a greater flight range without having to carry fuel or batteries, enabling an indefinite flight time. The demonstration was a collaborative effort between the Dryden Center at Edward's, California, where the aircraft was designed and built, and MSFC, where integration and testing of the laser and photovoltaic cells was done. Laser power beaming is a promising technology for consideration in new aircraft design and operation, and supports NASA's goals in the development of revolutionary aerospace technologies. Photographed with their invention are (from left to right): David Bushman and Tony Frackowiak, both of Dryden; and MSFC's Robert Burdine.

  10. Application of modern control design methodology to oblique wing research aircraft

    Science.gov (United States)

    Vincent, James H.

    1991-01-01

    A Linear Quadratic Regulator synthesis technique was used to design an explicit model following control system for the Oblique Wing Research Aircraft (OWRA). The forward path model (Maneuver Command Generator) was designed to incorporate the desired flying qualities and response decoupling. The LQR synthesis was based on the use of generalized controls, and it was structured to provide a proportional/integral error regulator with feedforward compensation. An unexpected consequence of this design approach was the ability to decouple the control synthesis into separate longitudinal and lateral directional designs. Longitudinal and lateral directional control laws were generated for each of the nine design flight conditions, and gain scheduling requirements were addressed. A fully coupled 6 degree of freedom open loop model of the OWRA along with the longitudinal and lateral directional control laws was used to assess the closed loop performance of the design. Evaluations were performed for each of the nine design flight conditions.

  11. A compact, fast UV photometer for measurement of ozone from research aircraft

    Directory of Open Access Journals (Sweden)

    R. S. Gao

    2012-09-01

    Full Text Available In situ measurements of atmospheric ozone (O3 are performed routinely from many research aircraft platforms. The most common technique depends on the strong absorption of ultraviolet (UV light by ozone. As atmospheric science advances to the widespread use of unmanned aircraft systems (UASs, there is an increasing requirement for minimizing instrument space, weight, and power while maintaining instrument accuracy, precision and time response. The design and use of a new, dual-beam, UV photometer instrument for in situ O3 measurements is described. A polarization optical-isolator configuration is utilized to fold the UV beam inside the absorption cells, yielding a 60-cm absorption length with a 30-cm cell. The instrument has a fast sampling rate (2 Hz at <200 hPa, 1 Hz at 200–500 hPa, and 0.5 Hz at ≥ 500 hPa, high accuracy (3% excluding operation in the 300–450 hPa range, where the accuracy may be degraded to about 5%, and excellent precision (1.1 × 1010 O3 molecules cm−3 at 2 Hz, which corresponds to 3.0 ppb at 200 K and 100 hPa, or 0.41 ppb at 273 K and 1013 hPa. The size (36 l, weight (18 kg, and power (50–200 W make the instrument suitable for many UASs and other airborne platforms. Inlet and exhaust configurations are also described for ambient sampling in the troposphere and lower stratosphere (1000–50 hPa that control the sample flow rate to maximize time response while minimizing loss of precision due to induced turbulence in the sample cell. In-flight and laboratory intercomparisons with existing O3 instruments show that measurement accuracy is maintained in flight.

  12. Program to compute the positions of the aircraft and of the aircraft sensor footprints

    Science.gov (United States)

    Paris, J. F. (Principal Investigator)

    1982-01-01

    The positions of the ground track of the aircraft and of the aircraft sensor footprints, in particular the metric camera and the radar scatterometer on the C-130 aircraft, are estimated by a program called ACTRK. The program uses the altitude, speed, and attitude informaton contained in the radar scatterometer data files to calculate the positions. The ACTRK program is documented.

  13. Users Guide for NASA Lewis Research Center DC-9 Reduced-Gravity Aircraft Program

    Science.gov (United States)

    Neumann, Eric S.; Withrow, James P.; Yaniec, John S.

    1996-01-01

    The document provides guidelines and information for users of the DC-9 Reduced-Gravity Aircraft Program. It describes the facilities, requirements for test personnel, equipment design and installation, mission preparation, and in-flight procedures. Those who have used the KC-135 reduced-gravity aircraft will recognize that many of the procedures and guidelines are the same.

  14. Flux measurements by the NRC Twin Otter atmospheric research aircraft: 1987-2011

    Science.gov (United States)

    Desjardins, Raymond L.; Worth, Devon E.; MacPherson, J. Ian; Bastian, Matthew; Srinivasan, Ramesh

    2016-03-01

    Over the past 30 years, the Canadian Twin Otter research group has operated an aircraft platform for the study of atmospheric greenhouse gas fluxes (carbon dioxide, ozone, nitrous oxide and methane) and energy exchange (latent and sensible heat) over a wide range of terrestrial ecosystems in North America. Some of the acquired data from these projects have now been archived at the Flight Research Laboratory and Agriculture and Agri-Food Canada. The dataset, which contains the measurements obtained in eight projects from 1987 to 2011 are now publicly available. All these projects were carried out in order to improve our understanding of the biophysical controls acting on land-surface atmosphere fluxes. Some of the projects also attempted to quantify the impacts of agroecosystems on the environment. To provide information on the data available, we briefly describe each project and some of the key findings by referring to previously published relevant work. As new flux analysis techniques are being developed, we are confident that much additional information can be extracted from this unique data set.

  15. Subsonic Ultra Green Aircraft Research: Phase II- Volume III-Truss Braced Wing Aeroelastic Test Report

    Science.gov (United States)

    Bradley, Marty K.; Allen, Timothy J.; Droney, Christopher

    2014-01-01

    This Test Report summarizes the Truss Braced Wing (TBW) Aeroelastic Test (Task 3.1) work accomplished by the Boeing Subsonic Ultra Green Aircraft Research (SUGAR) team, which includes the time period of February 2012 through June 2014. The team consisted of Boeing Research and Technology, Boeing Commercial Airplanes, Virginia Tech, and NextGen Aeronautics. The model was fabricated by NextGen Aeronautics and designed to meet dynamically scaled requirements from the sized full scale TBW FEM. The test of the dynamically scaled SUGAR TBW half model was broken up into open loop testing in December 2013 and closed loop testing from January 2014 to April 2014. Results showed the flutter mechanism to primarily be a coalescence of 2nd bending mode and 1st torsion mode around 10 Hz, as predicted by analysis. Results also showed significant change in flutter speed as angle of attack was varied. This nonlinear behavior can be explained by including preload and large displacement changes to the structural stiffness and mass matrices in the flutter analysis. Control laws derived from both test system ID and FEM19 state space models were successful in suppressing flutter. The control laws were robust and suppressed flutter for a variety of Mach, dynamic pressures, and angle of attacks investigated.

  16. 14 CFR 91.177 - Minimum altitudes for IFR operations.

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 2 2010-01-01 2010-01-01 false Minimum altitudes for IFR operations. 91.177 Section 91.177 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION... Instrument Flight Rules § 91.177 Minimum altitudes for IFR operations. (a) Operation of aircraft at...

  17. Determining the approach speed envelope of carrier aircraft

    Institute of Scientific and Technical Information of China (English)

    Geng Jianzhong; Yao Hailin; Duan Zhuoyi

    2013-01-01

    Many factors,such as deck motion and air wave,influence the determination of the approach speed which has an important effect on landing safety. Until recently,there are no design criteria about approach speed of carrier aircraft in the current standards and available publications. Therefore,the requirements of stall margin, longitudinal acceleration ability,altitude correction and field-of-view on approach speed were researched. Based on the flight dynamics model,the flight simulations were conducted to study the effect of the response time of en-gine,wave off requirements,elevator efficiency and deflection rate on the approach speed. The results presented that the approach longitudinal acceleration and altitude correction ability had crucial influence on the approach speed envelope of the aircraft. The limitations of the control requirements,field-of-view requirements and gear were also given through the simulation and analysis. Based on the above results,the approach speed envelope were determined.

  18. Using Hyperspectral Aircraft Remote Sensing to Support Ecosystems Services Research in New England Lakes and Ponds

    Science.gov (United States)

    Keith, D. J.; Milstead, B.; Walker, H.; Worthy, D.; Szykman, J.; Wusk, M.; Kagey, L.; Howell, C.; Snook, H.; Drueke, C.

    2010-12-01

    Northeastern lakes and ponds provide important ecosystem services to New England residents and visitors. These include the provisioning of abundant, clean water for consumption, agriculture, and industry as well as cultural services (recreation, aesthetics, and wilderness experiences) which enhance local economies and quality of life. Less understood, but equally important, are the roles that these lakes play in protecting all life through supportive services such as nutrient cycling. Nitrogen and phosphorus have a direct impact on the condition of fresh water lakes. Excesses of these nutrients can lead to eutrophication, toxic cyanobacteria blooms, decreased biodiversity, and loss of ecosystem function leading to a reduction in the availability and delivery of ecosystem services. In this study, we examined how variations in lake nutrient concentrations and phytoplankton pigment concentrations correlated with changes in the potential to provide cultural ecosystem services. Using a NASA Cessna 206 aircraft, hyperspectral data were collected during late summer 2009 from 55 lakes in New Hampshire, Massachusetts, Connecticut, and Rhode Island over a 2 day period. From the spectral data, algorithms were created which estimated concentrations of chlorophyll a, phycocyanin, and colored dissolved organic matter. The remotely sensed estimates were supplemented by in situ chlorophyll a, total nitrogen, total phosphorus and lake color data from 43 lakes sampled by field crews from the New England states. The purpose of this research is to understand how variations in lake nutrient concentrations and phytoplankton pigment concentrations correlate with changes in availability of cultural ecosystem services in the surveyed lakes. This dataset will be combined with information from the EPA National Lake Survey (2007), the EPA New England Lakes and Ponds Survey (2008) and the USGS SPARROW model to explore the association between lake condition and the provisioning of ecosystem

  19. Calibration of 3-D wind measurements on a single-engine research aircraft

    Science.gov (United States)

    Mallaun, C.; Giez, A.; Baumann, R.

    2015-08-01

    An innovative calibration method for the wind speed measurement using a boom-mounted Rosemount model 858 AJ air velocity probe is introduced. The method is demonstrated for a sensor system installed on a medium-size research aircraft which is used for measurements in the atmospheric boundary layer. The method encounters a series of coordinated flight manoeuvres to directly estimate the aerodynamic influences on the probe and to calculate the measurement uncertainties. The introduction of a differential Global Positioning System (DGPS) combined with a high-accuracy inertial reference system (IRS) has brought major advances to airborne measurement techniques. The exact determination of geometrical height allows the use of the pressure signal as an independent parameter. Furthermore, the exact height information and the stepwise calibration process lead to maximum accuracy. The results show a measurement uncertainty for the aerodynamic influence of the dynamic and static pressures of 0.1 hPa. The applied parametrisation does not require any height dependencies or time shifts. After extensive flight tests a correction for the flow angles (attack and sideslip angles) was found, which is necessary for a successful wind calculation. A new method is demonstrated to correct for the aerodynamic influence on the sideslip angle. For the three-dimensional (3-D) wind vector (with 100 Hz resolution) a novel error propagation scheme is tested, which determines the measurement uncertainties to be 0.3 m s-1 for the horizontal and 0.2 m s-1 for the vertical wind components.

  20. Calibration of 3-D wind measurements on a single engine research aircraft

    Science.gov (United States)

    Mallaun, C.; Giez, A.; Baumann, R.

    2015-02-01

    An innovative calibration method for the wind speed measurement using a boom mounted Rosemount model 858 AJ air velocity probe is introduced. The method is demonstrated for a sensor system installed on a medium size research aircraft which is used for measurements in the atmospheric boundary layer. The method encounters a series of coordinated flight manoeuvres to directly estimate the aerodynamic influences on the probe and to calculate the measurement uncertainties. The introduction of a differential Global Positioning System (DGPS) combined with a high accuracy Inertial Reference System (IRS) has brought major advances to airborne measurement techniques. The exact determination of geometrical height allows the use of the pressure signal as an independent parameter. Furthermore, the exact height information and the stepwise calibration process lead to maximum accuracy. The results show a measurement uncertainty for the aerodynamic influence of the dynamic and static pressures of 0.1 hPa. The applied parametrisation does not require any height dependencies or time shifts. After extensive flight tests a correction for the flow angles (attack and sideslip angles) was found, which is necessary for a successful wind calculation. A new method is demonstrated to correct for the aerodynamic influence on the sideslip angle. For the 3-D wind vector (with 100 Hz resolution) a novel error propagation scheme is tested, which determines the measurement uncertainties to be 0.3 m s-1 for the horizontal and 0.2 m s-1 for the vertical wind components.

  1. Estimation of dynamic rotor loads for the rotor systems research aircraft: Methodology development and validation

    Science.gov (United States)

    Duval, R. W.; Bahrami, M.

    1985-01-01

    The Rotor Systems Research Aircraft uses load cells to isolate the rotor/transmission systm from the fuselage. A mathematical model relating applied rotor loads and inertial loads of the rotor/transmission system to the load cell response is required to allow the load cells to be used to estimate rotor loads from flight data. Such a model is derived analytically by applying a force and moment balance to the isolated rotor/transmission system. The model is tested by comparing its estimated values of applied rotor loads with measured values obtained from a ground based shake test. Discrepancies in the comparison are used to isolate sources of unmodeled external loads. Once the structure of the mathematical model has been validated by comparison with experimental data, the parameters must be identified. Since the parameters may vary with flight condition it is desirable to identify the parameters directly from the flight data. A Maximum Likelihood identification algorithm is derived for this purpose and tested using a computer simulation of load cell data. The identification is found to converge within 10 samples. The rapid convergence facilitates tracking of time varying parameters of the load cell model in flight.

  2. Performance of WVSS-II hygrometers on the FAAM Research Aircraft

    Directory of Open Access Journals (Sweden)

    A. K. Vance

    2014-08-01

    Full Text Available We compare the performance of five hygrometers fitted to the Facility for Airborne Atmospheric Measurement's (FAAM BAe 146-301 research aircraft using data from approximately one hundred flights executed over the course of two years under a wide range of conditions. Bulk comparison of cloud free data show good agreement between chilled mirror hygrometers and a WVSS-II fed from a modified Rosemount inlet but that a WVSS-II fed from the standard flush inlet appears to over read compared to the other instruments, except at higher humidities. Statistical assessment of hygrometer performance in cloudy conditions is problematic due to the variable nature of clouds, so a number of case studies are used instead to investigate the performance of the hygrometers in sub optimal conditions. It is found that the flush inlet is not susceptible to either liquid or solid water but that the Rosemount inlet has a significant susceptibility to liquid water; it is not susceptible to ice. In all conditions the WVSS-II respond much more rapidly than the chilled mirror devices, with the flush inlet-fed WVSS-II being more rapid than that connected to the Rosemount.

  3. Research on the Power Recovery of Diesel Engines with Regulated Two-Stage Turbocharging System at Different Altitudes

    Directory of Open Access Journals (Sweden)

    Hualei Li

    2014-01-01

    Full Text Available Recovering the boost pressure is very important in improving the dynamic performance of diesel engines at high altitudes. A regulated two-stage turbocharging system is an adequate solution for power recovery of diesel engines. In the present study, the change of boost pressure and engine power at different altitudes was investigated, and a regulated two-stage turbocharging system was constructed with an original turbocharger and a matched low pressure turbocharger. The valve control strategies for boost pressure recovery, which formed the basis of the power recovery method, are presented here. The simulation results showed that this system was effective in recovering the boost pressure at different speeds and various altitudes. The turbine bypass valve and compressor bypass valve had different modes to adapt to changes in operating conditions. The boost pressure recovery could not ensure power recovery over the entire operating range of the diesel engine, because of variation in overall turbocharger efficiency. The fuel-injection compensation method along with the valve control strategies for boost pressure recovery was able to reach the power recovery target.

  4. Assessing Regional Scale Fluxes of Mass, Momentum, and Energy with Small Environmental Research Aircraft

    Science.gov (United States)

    Zulueta, Rommel Callejo

    Natural ecosystems are rarely structurally or functionally homogeneous. This is true for the complex coastal regions of Magdalena Bay, Baja California Sur, Mexico, and the Barrow Peninsula on the Arctic Coastal Plain of Alaska. The coastal region of Magdalena Bay is comprised of the Pacific coastal ocean, eutrophic lagoon, mangroves, and desert ecosystems all adjacent and within a few kilometers, while the Barrow Peninsula is a mosaic of small ponds, thaw lakes, different aged vegetated thaw-lake basins ( VDTLBs ) and interstitial tundra which have been dynamically formed by both short- and long-term processes. We used a combination of tower- and small environmental research aircraft (SERA)-based eddy covariance measurements to characterize the spatial and temporal patterns of CO2, latent, and sensible heat fluxes along with MODIS NDVI, and land surface information, to scale the SERA-based CO2 fluxes up to the regional scale. In the first part of this research, the spatial variability in ecosystem fluxes from the Pacific coastal ocean, eutrophic lagoon, mangroves, and desert areas of northern Magdalena Bay were studied. SERA-derived average midday CO2 fluxes from the desert showed a slight uptake of -1.32 mumol CO2 m-2 s-1, the coastal ocean also showed uptake of -3.48 mumol CO2 m-2 s -1, and the lagoon mangroves showed the highest uptake of -8.11 mumol CO2 m-2 s-1. Additional simultaneous measurements of NDVI allowed simple linear modeling of CO2 flux as a function of NDVI for the mangroves of the Magdalena Bay region. In the second part of this research, the spatial variability of ecosystem fluxes across the 1802 km2 Barrow Peninsula region was studied. During typical 2006 summer conditions, the midday hourly CO2 flux over the region was -2.04 x 105 kgCO2 hr-1. The CO2 fluxes among the interstitial tundra, Ancient and Old VDTLBs, as well as between the Medium and Young VDTLBs were not significantly different. Combined, the interstitial tundra and Old and Ancient

  5. Aerodynamic and Electromagnetic Characteristics Research of High-altitude Long-endurance Early Warning Unmanned Aerial Vehicles%高空长航时无人预警机气动及电磁特性研究

    Institute of Scientific and Technical Information of China (English)

    任武; 周洲; 王正平

    2012-01-01

    高空长航时无人预警机具有反应迅速、成本低廉、覆盖范围广等优点,是侦察卫星、高空飞艇等侦察平台的重要补充.基于天线特性,提出两种将柱面天线与高空长航时无人机融合的布局形式,将雷达反射面天线布置于无人机中段,并分析两种布局在气动及电磁特性的差异,为此类特种高空长航时无人预警机的设计提供了一定的理论依据.%The high-altitude long-endurance ( HALE) early warning unmanned aerial vehicles ( UAV) had become an important complementarity of reconnaissance satellite and high-altitude airship as reconnaissance platform, since it was excellence in quick response, low cost, vast coverage area, etc. Based on the character of antenna, two high-altitude long-endurance early warning unmanned aerial vehicles layouts combined with antenna which was set in the middle of the whole plane were put forward. And then analyzed the aerodynamic and electromagnetic character difference between the two layouts. A certain theory evidence is provided for the design of these special high altitude long-endurance early warning aircraft.

  6. 飞机租赁定价模型研究%Pricing Model Research on Aircraft Operating Lease

    Institute of Scientific and Technical Information of China (English)

    丁勇; 葛翔

    2015-01-01

    飞机租赁的定价对于飞机租赁公司的盈利能力有着重要影响,而国内有关飞机租赁业务定价问题的研究尚处于起步阶段。提出了飞机租赁定价模型采用的是净现值原理,将出租人的资金成本、承租人的经营能力、飞机的折旧抵税、残值等影响定价的要素加以量化,最终得出租赁双方可以接受的价格区间,通过对组成定价的各要素进行分析,进而得出提升我国飞机租赁行业竞争力的对策建议。%The pricing method of aircraft leasing greatly affects aircraft leasing companies’ profitability . However ,domestic research remains in the primary stage of the issue .A pricing model individually de‐signed for operating lease has been proposed ,which is based on the net present value method .The model results in a price range agreed by lessee and lessor by the quantification of such factors as lessor’s capital cost ,lessee’s business capabilities ,aircraft salvage ,deduction for depreciation and etc .Through the anal‐ysis of these factors ,we put forward policy suggestions aimed at enhancing the competitiveness of China’ s aircraft leasing industry .

  7. Fulminant high altitude blindness.

    Science.gov (United States)

    Mashkovskiy, Evgeny; Szawarski, Piotr; Ryzhkov, Pavel; Goslar, Tomaz; Mrak, Irena

    2016-06-01

    Prolonged altitude exposure even with acclimatization continues to present a physiological challenge to all organ systems including the central nervous system. We describe a case of a 41-year-old Caucasian female climber who suffered severe visual loss that was due to possible optic nerve pathology occurring during a high altitude expedition in the Himalayas. This case is atypical of classic high altitude cerebral oedema and highlights yet another danger of prolonged sojourn at extreme altitudes. PMID:27601532

  8. The European Research Infrastructure IAGOS - From dedicated field studies to routine observations of the atmosphere by instrumented passenger aircraft

    Science.gov (United States)

    Petzold, Andreas; Volz-Thomas, Andreas; Gerbig, Christoph; Thouret, Valerie; Cammas, Jean-Pierre; Brenninkmeijer, Carl A. M.; Iagos Team

    2013-04-01

    The global distribution of trace species is controlled by a complex interplay between natural and anthropogenic sources and sinks, atmospheric short- to long-range transport, and in future by diverse, largely not yet quantified feedback mechanisms such as enhanced evaporation of water vapour in a warming climate or possibly the release of methane from melting marine clathrates. Improving global trace gas budgets and reducing the uncertainty of climate predictions crucially requires representative data from routine long-term observations as independent constraint for the evaluation and improvement of model parameterizations. IAGOS (In-service Aircraft for a Global Observing System; www.iagos.org) is a new European Research Infrastructure which operates a unique global observing system by deploying autonomous instruments aboard a fleet of passenger aircraft. IAGOS consists of two complementary building blocks: IAGOS-CORE deploys newly developed high-tech instrumentation for regular in-situ measurements of atmospheric chemical species (O3, CO, CO2, NOx, NOy, H2O, CH4), aerosols and cloud particles. Involved airlines ensure global operation of the network. In IAGOS-CARIBIC a cargo container is operated as a flying laboratory aboard one passenger aircraft. IAGOS aims at the provision of long-term, frequent, regular, accurate, and spatially resolved in-situ observations of the atmospheric chemical composition in the UTLS and the extra tropical troposphere and on vertical profiles of greenhouse gases, reactive trace gases and aerosols throughout the troposphere. It builds on almost 20 years of scientific and technological expertise gained in the research projects MOZAIC (Measurement of Ozone and Water Vapour on Airbus In-service Aircraft) and CARIBIC (Civil Aircraft for the Regular Investigation of the Atmosphere Based on an Instrument Container). The European consortium includes research centres, universities, national weather services, airline operators and aviation

  9. Flight simulation program for high altitude long endurance unmanned vehicle; Kokodo mujinki no hiko simulation program

    Energy Technology Data Exchange (ETDEWEB)

    Suzuki, H.; Hashidate, M. [National Aerospace Laboratory, Tokyo (Japan)

    1995-11-01

    An altitude of about 20 km has the atmospheric density too dilute for common aircraft, and the air resistance too great for satellites. Attention has been drawn in recent years on a high-altitude long-endurance unmanned vehicle that flies at this altitude for a long period of time to serve as a wave relaying base and perform traffic control. Therefore, a development was made on a flight simulation program to evaluate and discuss the guidance and control laws for the high-altitude unmanned vehicle. Equations of motion were derived for three-dimensional six freedom and three-dimensional three freedom. Aerodynamic characteristics of an unmanned vehicle having a Rectenna wing were estimated, and formulation was made according to the past research results on data of winds that the unmanned vehicle is anticipated to encounter at an altitude of 20 km. Noticing the inside of a horizontal plane, a proposal was given on a guidance law that follows a given path. A flight simulation was carried out to have attained a prospect that the unmanned vehicle may be enclosed in a limited space even if the vehicle is encountered with a relatively strong wind. 18 refs., 20 figs., 1 tab.

  10. Radiation exposure monitoring in civil aircraft

    Science.gov (United States)

    Schrewe, Ulrich J.

    1999-02-01

    Based on the 1990 Recommendation of the ICRP (ICRP Publication 60, Pergamon Press, Oxford, 1991) a European Directive [Official J. Eur. Communities 19 (1996) L159, 1-114] commits the European Union (EU) member states to revise their national radiation protection laws by the year 2000 such that the exposure of aircrews to the increased cosmic radiation prevailing at aviation flight altitudes will be treated as occupational risks. A consequence will be that employers must assess the aircrew exposure. The ACREM (Air Crew Radiation Exposure Monitoring) research project intends to investigate practically methods for aircraft dose equivalent determination. The in-flight measurements were carried out on cargo aircraft. Field calibrations were performed using Tissue-Equivalent Proportional Counters (TEPC) as the reference instrument. Various monitors were used to investigate the spatial doserate distribution. The measured data were collated according to the different altitudes and geomagnetic latitudes. The results obtained from various in-flight measurements are reported and a concept for a future routine dose assessment for aircrew is proposed.

  11. Aircraft operations management manual

    Science.gov (United States)

    1992-01-01

    The NASA aircraft operations program is a multifaceted, highly diverse entity that directly supports the agency mission in aeronautical research and development, space science and applications, space flight, astronaut readiness training, and related activities through research and development, program support, and mission management aircraft operations flights. Users of the program are interagency, inter-government, international, and the business community. This manual provides guidelines to establish policy for the management of NASA aircraft resources, aircraft operations, and related matters. This policy is an integral part of and must be followed when establishing field installation policy and procedures covering the management of NASA aircraft operations. Each operating location will develop appropriate local procedures that conform with the requirements of this handbook. This manual should be used in conjunction with other governing instructions, handbooks, and manuals.

  12. Evaluation of V/STOL research aircraft design. [landing approaches, propulsion/control, piloted moving base simulator

    Science.gov (United States)

    Deckert, W. H.; Holzhauser, C. A.

    1973-01-01

    The evaluation and evolution of direct jet lift V/STOL transport aircraft designs are discussed. The V/STOL transport design selected as an example is a lift-fan design that was evaluated as a candidate configuration for a possible future V/STOL research transport. The paper includes discussion of potential advanced V/STOL landing approach profiles as key design requirements for V/STOL aircraft, description and experimental results of an integrated propulsion/control system designed to achieve desired advanced V/STOL near-terminal operating capabilities, and results from evaluating V/STOL designs on piloted moving-base simulators. This paper discusses use of the piloted moving-base simulator as a design tool for evolving satisfactory V/STOL stabilization and propulsion/control systems. Included are problems and solutions identified during simulation of simultaneous decelerating/descent steep curved landing approaches under instrument flight conditions. Simulation results are also compared to flight results obtained with the DO-31 V/STOL research transport.

  13. An inverse modelling approach for frequency response correction of capacitive humidity sensors in ABL research with small unmanned aircraft

    Directory of Open Access Journals (Sweden)

    N. Wildmann

    2014-05-01

    Full Text Available The measurement of water-vapour concentration in the atmosphere is an ongoing challenge in environmental research. Satisfactory solutions are present for ground-based meteorological stations and measurements of mean values. However, advanced research of thermodynamic processes also aloft, above the surface layer and especially in the atmospheric boundary layer (ABL, requires the resolution of small-scale turbulence. Sophisticated optical instruments are used in airborne meteorology with manned aircraft to achieve the necessary fast response measurements in the order of 1 Hz (e.g. LiCor 7500. Since these instruments are too large and heavy for the application on the promising platforms of small remotely piloted aircraft (RPA, a method is presented in this study, that enhances small capacitive humidity sensors to be able to resolve turbulent eddies in the order of 10 m. For this purpose a physical and dynamical model of such a sensor is described and inverted in order to restore original water vapour fluctuations from sensor measurements. Examples of flight measurements show how the method can be used to correct vertical profiles and resolve turbulence spectra up to about 3 Hz.

  14. An inverse modelling approach for frequency response correction of capacitive humidity sensors in ABL research with small unmanned aircraft

    Science.gov (United States)

    Wildmann, N.; Kaufmann, F.; Bange, J.

    2014-05-01

    The measurement of water-vapour concentration in the atmosphere is an ongoing challenge in environmental research. Satisfactory solutions are present for ground-based meteorological stations and measurements of mean values. However, advanced research of thermodynamic processes also aloft, above the surface layer and especially in the atmospheric boundary layer (ABL), requires the resolution of small-scale turbulence. Sophisticated optical instruments are used in airborne meteorology with manned aircraft to achieve the necessary fast response measurements in the order of 1 Hz (e.g. LiCor 7500). Since these instruments are too large and heavy for the application on the promising platforms of small remotely piloted aircraft (RPA), a method is presented in this study, that enhances small capacitive humidity sensors to be able to resolve turbulent eddies in the order of 10 m. For this purpose a physical and dynamical model of such a sensor is described and inverted in order to restore original water vapour fluctuations from sensor measurements. Examples of flight measurements show how the method can be used to correct vertical profiles and resolve turbulence spectra up to about 3 Hz.

  15. Experimental research on photocatalytic oxidation air purification technology applied to aircraft cabins

    DEFF Research Database (Denmark)

    Sun, Yuexia; Fang, Lei; Wyon, David Peter;

    2008-01-01

    The experiment presented in this report was performed in a simulated aircraft cabin to evaluate the air cleaning effects of two air purification devices that used photocatalytic oxidation (PCO) technology. Objective physical, chemical and physiological measurements and subjective human assessments...... were used for the evaluation. Comparisons were made between conditions with and without the PCO units installed in the re-circulated air system. Four groups of 17 subjects were exposed for 7 h to each test condition. Chemical analysis indicates that ethanol, isoprene and toluene were decomposed...

  16. Experimental research on photocatalytic oxidation air purification technology applied to aircraft cabins

    DEFF Research Database (Denmark)

    Sun, Yuexia; Fang, Lei; Wyon, David P.;

    2005-01-01

    The experiment presented in this report was performed in a simulated aircraft cabin to evalu-ate the air cleaning effects of two air purification devices using Photocatalytic Oxidation (PCO) technology. Objective physical, chemical and physiological measurements and subjec-tive human assessments...... were used for the evaluation. Comparisons were made between con-ditions with and without the PCO units installed in the re-circulated air system. Four groups of 17 subjects were exposed for 7 hours to each test condition. Chemical analysis indicates that Ethanol, Isoprene and Toluene were decomposed...

  17. Research on High-altitude Airship Thermal Analysis%高空飞艇热分析研究

    Institute of Scientific and Technical Information of China (English)

    江京; 慎利峰

    2012-01-01

    According to the latitude and the sun running rules at the fixed-pointed time zone, as well as flying posture of the high-altitude airship, the finite element modeling of the envelope and the Helium in- flated of the airship are established, and the temperature calculation is carried out by FEM. The rules of the average temperature of the Helium inflated in the airship are obtained in relation to the time chan- ging, and also the temperature range of Helium is obtained. As to comparing the result of the temperature calculation of Helium without the thermal capacity of the airship envelope, the difference of the analysis result of the Helium with and without the thermal capacity of the airship envelope has been found. The necessity of the accounting of the thermal capacity, the weight of the envelope and the solar cell is indica- ted by the analysis of the calculation results.%根据高空飞艇的定点运行区域地球纬度、定点运行时域的太阳运行规律,以及高空飞艇的飞行姿态,对高空飞艇囊体及所包容的氦气建立有限元物理模型并进行有限元热分析,得到高空飞艇艇内氦气平均温度在太阳辐射情况下随时间变化的规律及温差范围。同时,与不包括飞艇囊体热容量的飞艇氦气热分析进行了比较,得到了高空飞艇热分析中加入囊体材料热容及忽略囊体热容的差异。研究证明高空飞艇的热分析必须考虑囊体的质量和热容及薄膜电池的质量和热容。

  18. Research and Application on Civil Aircraft Ground Flotation%民用飞机地面漂浮性分析研究及应用

    Institute of Scientific and Technical Information of China (English)

    房务官; 魏小辉; 宋晓晨; 吴卜圣

    2012-01-01

    民用飞机地面漂浮性是评估飞机-机场相容性的一个重要指标,其直接影响到飞机设计参数选择以及地面适应性的优劣.在总体概念设计阶段就必须对飞机的漂浮性能进行分析评估,从而选择恰当的飞机参数.对民用飞机在刚性道面和柔性道面上漂浮性分析方法做了简要说明,并针对国际民用航空组织所推广使用的ACN/PCN(飞机分类号/机场分类号)方法进行了详细分析研究,在此基础上,开发出了飞机地面漂浮性分析软件.通过直接输入飞机相关参数可以快速准确地计算出飞机分类号ACN值.可以有效地对飞机地面漂浮性进行评估和优化,从而解决了用手工方式评估飞机地面漂浮性时的繁琐及不准确,并降低了对从事飞机地面漂浮性计算的人员要求.%Civil aircraft ground flotation is an important evaluation indicator of aircraft- airport compatibility , which affects the aircraft design parameters selection and the pros and cons of the ground adaptability directly. In the general conceptual design stage, the analysis and evaluation of the aircraft flotation must be done to select the appropriate parameters of the aircraft. This paper briefly describes the analysis methods of civil aircraft floating in the rigid pavement and flexible pavement, and carried out a detailed analysis and research for the ACN / PCN,the aircraft and airport's class number method,that is promoted by International Civil Aviation Organization and developed a aircraft ground flotation analysis software on that base. Inputting the relevant aircraft parameters directly, it can calculate the value the class number of aircraft, ACN, quickly and accurately. The software can effectively evaluate and optimize aircraft ground flotation , thus solve the problem of the complication and inaccuracy caused by evaluating the aircraft ground flotation by hand. In addition,it also reduces the demand for the personnel engaged in it.

  19. Update on Piloted and Un-Piloted Aircraft at NASA Dryden

    Science.gov (United States)

    DelFrate, John H.

    2007-01-01

    This viewgraph presentation reviews the NASA Dryden Flight Research Center's (DFRC) environment for testing of experimental aircraft. Included are a satellite view of the Dryden locale, and a summary of the capabilities at DFRC. It reviews the capabilites of High Altitude Platform (HAP) testing; Gulfstream III (1.)Unmanned Aerial Vehicle (UAV) synthetic aperture radar (SAR) (2) Precision Trajectory Capability Global Hawk (ACTD); ER-2; Ikhana (Predator B);

  20. A study of the stable boundary layer in strong gap flows in northwest Greenland using a research aircraft

    Science.gov (United States)

    Heinemann, Günther; Drüe, Clemens

    2016-04-01

    Gap flows and the stable boundary layer (SBL) were studied in northwest Greenland during the aircraft-based experiment IKAPOS (Investigation of Katabatic winds and Polynyas during Summer) in June 2010. The measurements were performed using the research aircraft POLAR 5 of Alfred Wegener Institute (AWI, Bremerhaven). Besides navigational and basic meteorological instrumentation, the aircraft was equipped with radiation and surface temperature sensors, two laser altimeters, and video and digital cameras. In order to determine turbulent heat and momentum fluxes, POLAR 5 was instrumented with a turbulence measurement system collecting data on a nose boom with a sampling rate of 100 Hz. In the area of the Nares Strait a stable, but fully turbulent boundary layer with strong winds of 15 m s-1 to 20 m s-1 was found during conditions of relatively warm synoptically induced northerly winds through the Nares Strait. Strong surface inversions were present in the lowest 100 m to 200 m. As a consequence of channeling effects a well-pronounced low-level jet (LLJ) system was documented. The channeling process is consistent with gap flow theory and can be shown to occur at the topographic gap between Greenland and Canada represented by the Smith Sound. While the flow through the gap and over the surrounding mountains leads to the lowering of isotropic surfaces and the acceleration of the flow, the strong turbulence associated with the LLJ leads to the development of an internal thermal SBL past the gap. Turbulence statistics in this fully turbulent SBL can be shown to follow the local scaling behaviour.

  1. The Arctic Research of the Composition of the Troposphere from Aircraft and Satellites (ARCTAS mission: design, execution, and first results

    Directory of Open Access Journals (Sweden)

    D. J. Jacob

    2010-06-01

    Full Text Available The NASA Arctic Research of the Composition of the Troposphere from Aircraft and Satellites (ARCTAS mission was conducted in two 3-week deployments based in Alaska (April 2008 and western Canada (June–July 2008. Its goal was to better understand the factors driving current changes in Arctic atmospheric composition and climate, including (1 influx of mid-latitude pollution, (2 boreal forest fires, (3 aerosol radiative forcing, and (4 chemical processes. The June–July deployment was preceded by one week of flights over California (ARCTAS-CARB focused on (1 improving state emission inventories for greenhouse gases and aerosols, (2 providing observations to test and improve models of ozone and aerosol pollution. ARCTAS involved three aircraft: a DC-8 with a detailed chemical payload, a P-3 with an extensive aerosol and radiometric payload, and a B-200 with aerosol remote sensing instrumentation. The aircraft data augmented satellite observations of Arctic atmospheric composition, in particular from the NASA A-Train. The spring phase (ARCTAS-A revealed pervasive Asian pollution throughout the Arctic as well as significant European pollution below 2 km. Unusually large Siberian fires in April 2008 caused high concentrations of carbonaceous aerosols and also affected ozone. Satellite observations of BrO column hotspots were found not to be related to Arctic boundary layer events but instead to tropopause depressions, suggesting the presence of elevated inorganic bromine (5–10 pptv in the lower stratosphere. Fresh fire plumes from Canada and California sampled during the summer phase (ARCTAS-B indicated low NOx emission factors from the fires, rapid conversion of NOx to PAN, no significant secondary aerosol production, and no significant ozone enhancements except when mixed with urban pollution.

  2. Flight Control Design for a Tailless Aircraft Using Eigenstructure Assignment

    OpenAIRE

    Clara Nieto-Wire; Kenneth Sobel

    2011-01-01

    We apply eigenstructure assignment to the design of a flight control system for a wind tunnel model of a tailless aircraft. The aircraft, known as the innovative control effectors (ICEs) aircraft, has unconventional control surfaces plus pitch and yaw thrust vectoring. We linearize the aircraft in straight and level flight at an altitude of 15,000 feet and Mach number 0.4. Then, we separately design flight control systems for the longitudinal and lateral dynamics. We use a control allocation ...

  3. LOW ALTITUDE AIRSHIPS FOR SEAMLESS MOBILE COMMUNICATION IN AIR TRAVEL

    OpenAIRE

    Madhu D; Santhoshkumar M K; Swarnalatha Srinivas; Narendra Kumar G

    2014-01-01

    The Aviation Administration policy prohibits the use of mobile phones in Aircraft during transition for the reason it may harm their communication system due to Electromagnetic interference. In case the user wants to access cellular network at higher altitudes, base station access is a problem. Large number of channels are allocated to a single user moving at high speed by various Base Stations in the vicinity to service the request requiring more resources. Low Altitude Platfo...

  4. Hybrid upper surface blown flap propulsive-lift concept for the Quiet Short-Haul Research Aircraft

    Science.gov (United States)

    Cochrane, J. A.; Carros, R. J.

    1975-01-01

    The hybrid upper surface blowing concept consists of wing-mounted turbofan engines with a major portion of the fan exhaust directed over the wing upper surface to provide high levels of propulsive lift, but with a portion of the fan airflow directed over selected portions of the airframe to provide boundary layer control. NASA-sponsored preliminary design studies identified the hybrid upper surface blowing concept as the best propulsive lift concept to be applied to the Quiet Short-Haul Research Aircraft (QSRA) that is planned as a flight facility to conduct flight research at low noise levels, high approach lift coefficients, and steep approaches. Data from NASA in-house and NASA-sponsored small and large-scale wind tunnel tests of various configurations using this concept are presented.

  5. Research on the Cockpit Design Characteristics for Commercial Aircraft%商用飞机驾驶舱造型设计特征研究

    Institute of Scientific and Technical Information of China (English)

    刘岗; 刘春荣

    2015-01-01

    This paper introduces the history and current situation of cockpit modeling design from Commercial Air-craft Corporation of China and other nations. First of all,a wide research was taken including an investigation of 5 different aircrafts and a collection of different types of aircraft cockpit pictures. Based on these, the design logic of different aircraft manufacturers was concluded. Sixty six cockpits from 12 aircraft companies are used as the cus-tomer research and cluster analysis and 10 typical cockpits are chosen from them. After that, the cockpit design characteristics and differences from main aircraft manufacturers are analyzed. The research provides a good refer-ence for new aircraft cockpit design.%介绍了国内外商用飞机驾驶舱设计的历史及现状,在分析多类飞机驾驶舱造型设计图片资料的基础上,探讨主要飞机制造商驾驶舱造型设计的特征。依据驾驶舱造型的相似性,对国际上12家商用飞机制造商的66款机型的驾驶舱进行聚类分析和多维尺度分析,挑选出10款有代表性的驾驶舱。在提取代表性驾驶舱造型特征线后,分析主要飞机制造商的驾驶舱造型设计特点及差异,为新型飞机驾驶舱造型设计提供参考。

  6. Application research of centrifugal investment cast TiAl component used for advanced aircraft engine

    Institute of Scientific and Technical Information of China (English)

    李俊涛; 李世琼; 张继; 马万青; 邹敦叙; 仲增墉

    2002-01-01

    A more complex structural component with small size and very thin walls and blades used for advanced aircraft engine was fabricated well by induction skull melting and centrifugal investment casting with a proper ceramic mold. The tensile elongation and ultimate strength of the hot isostatically pressed (HIPped) Ti-46.5Al-2.5V-1Cr (mole fraction, %) casting alloy sare up to 2.5% and 645 Mpa at room temperature, and 31% and 593 Mpa a t 800 ℃. The fracture roughness at room temperature is up to 28 Mpa*m1/2 . The endurance tensile strength at 800 ℃ for 150 h, is higher than 200 Mpa. The high cycle rotary bending fatigue strengths for 1×107 cycles at room temperature and 800 ℃ a re 412 Mpa and 270 Mpa, respectively.

  7. Fiber Optic Experience with the Smart Actuation System on the F-18 Systems Research Aircraft

    Science.gov (United States)

    Zavala, Eddie

    1997-01-01

    High bandwidth, immunity to electromagnetic interference, and potential weight savings have led to the development of fiber optic technology for future aerospace vehicle systems. This technology has been incorporated in a new smart actuator as the primary communication interface. The use of fiber optics simplified system integration and significantly reduced wire count. Flight test results showed that fiber optics could be used in aircraft systems and identified critical areas of development of fly-by-light technology. This paper documents the fiber optic experience gained as a result of this program, and identifies general design considerations that could be used in a variety of specific applications of fiber optic technology. Environmental sensitivities of fiber optic system components that significantly contribute to optical power variation are discussed. Although a calibration procedure successfully minimized the effect of fiber optic sensitivities, more standardized calibration methods are needed to ensure system operation and reliability in future aerospace vehicle systems.

  8. HIGH-ALTITUDE ILLNESS

    Directory of Open Access Journals (Sweden)

    Dwitya Elvira

    2015-05-01

    Full Text Available AbstrakHigh-altitude illness (HAI merupakan sekumpulan gejala paru dan otak yang terjadi pada orang yang baru pertama kali mendaki ke ketinggian. HAI terdiri dari acute mountain sickness (AMS, high-altitude cerebral edema (HACE dan high-altitude pulmonary edema (HAPE. Tujuan tinjauan pustaka ini adalah agar dokter dan wisatawan memahami risiko, tanda, gejala, dan pengobatan high-altitude illness. Perhatian banyak diberikan terhadap penyakit ini seiring dengan meningkatnya popularitas olahraga ekstrim (mendaki gunung tinggi, ski dan snowboarding dan adanya kemudahan serta ketersediaan perjalanan sehingga jutaan orang dapat terpapar bahaya HAI. Di Pherice, Nepal (ketinggian 4343 m, 43% pendaki mengalami gejala AMS. Pada studi yang dilakukan pada tempat wisata di resort ski Colorado, Honigman menggambarkan kejadian AMS 22% pada ketinggian 1850 m sampai 2750 m, sementara Dean menunjukkan 42% memiliki gejala pada ketinggian 3000 m. Aklimatisasi merupakan salah satu tindakan pencegahan yang dapat dilakukan sebelum pendakian, selain beberapa pengobatan seperti asetazolamid, dexamethasone, phosopodiestrase inhibitor, dan ginko biloba.Kata kunci: high-altitude illness, acute mountain sickness, edema cerebral, pulmonary edema AbstractHigh-altitude illness (HAI is symptoms of lung and brain that occurs in people who first climb to altitude. HAI includes acute mountain sickness (AMS, high-altitude cerebral edema (HACE and high altitude pulmonary edema (HAPE. The objective of this review was to understand the risks, signs, symptoms, and treatment of high-altitude illness. The attention was given to this disease due to the rising popularity of extreme sports (high mountain climbing, skiing and snowboarding and the ease and availability of the current travelling, almost each year, millions of people could be exposed to the danger of HAI. In Pherice, Nepal (altitude 4343 m, 43% of climbers have symptoms of AMS. Furthermore, in a study conducted at sites in

  9. Braking performance of aircraft tires

    Science.gov (United States)

    Agrawal, Satish K.

    This paper brings under one cover the subject of aircraft braking performance and a variety of related phenomena that lead to aircraft hydroplaning, overruns, and loss of directional control. Complex processes involving tire deformation, tire slipping, and fluid pressures in the tire-runway contact area develop the friction forces for retarding the aircraft; this paper describes the physics of these processes. The paper reviews the past and present research efforts and concludes that the most effective way to combat the hazards associated with aircraft landings and takeoffs on contaminated runways is by measuring and displaying in realtime the braking performance parameters in the aircraft cockpit.

  10. [Mountaineering and altitude sickness].

    Science.gov (United States)

    Maggiorini, M

    2001-06-01

    Almost every second trekker or climber develops two to three symptoms of the high altitude illness after a rapid ascent (> 300 m/day) to an altitude above 4000 m. We distinguish two forms of high altitude illness, a cerebral form called acute mountain sickness and a pulmonary form called high altitude pulmonary edema. Essentially, acute mountain sickness is self-limiting and benign. Its symptoms are mild to moderate headache, loss of appetite, nausea, dizziness and insomnia. Nausea rarely progresses to vomiting, but if it does, this may anticipate a progression of the disease into the severe form of acute mountain sickness, called high altitude cerebral edema. Symptoms and signs of high altitude cerebral edema are severe headache, which is not relieved by acetaminophen, loss of movement coordination, ataxia and mental deterioration ending in coma. The mechanisms leading to acute mountain sickness are not very well understood; the loss of cerebral autoregulation and a vasogenic type of cerebral edema are being discussed. High altitude pulmonary edema presents in roughly twenty percent of the cases with mild symptoms of acute mountain sickness or even without any symptoms at all. Symptoms associated with high altitude pulmonary edema are incapacitating fatigue, chest tightness, dyspnoe at the minimal effort that advances to dyspnoe at rest and orthopnoe, and a dry non-productive cough that progresses to cough with pink frothy sputum due to hemoptysis. The hallmark of high altitude pulmonary edema is an exaggerated hypoxic pulmonary vasoconstriction. Successful prophylaxis and treatment of high altitude pulmonary edema using nifedipine, a pulmonary vasodilator, indicates that pulmonary hypertension is crucial for the development of high altitude pulmonary edema. The primary treatment of high altitude illness consists in improving hypoxemia and acclimatization. For prophylaxis a slow ascent at a rate of 300 m/day is recommended, if symptoms persist, acetazolamide at a

  11. 基于改进蚁群算法的飞机低空突防航路规划%Algorithm for Low Altitude Penetration Aircraft Path Planning with Improved Ant Colony Algorithm

    Institute of Scientific and Technical Information of China (English)

    叶文; 马登武; 范洪达

    2005-01-01

    蚁群算法是一种新型的基于群体的仿生算法.采用蚁群算法实现了飞机低空突防的航路规划,为航路规划问题提供了新的解决思路.并对原始蚁群算法进行了改进,提出了保留最优解、自适应选择策略和自适应信息素调整准则,有效地提高了算法的收敛速度和解的性能.最后用计算机进行了仿真,取得了较好的结果.%The ant colony algorithm is a new class of population basic algorithm. The path planning is realized by the use of ant colony algorithm when the plane executes the low altitude penetration, which provides a new method for the path planning. In the paper the traditional ant colony algorithm is improved, and measures of keeping optimization, adaptively selecting and adaptively adjusting are applied, by which better path at higher convergence speed can be found. Finally the algorithm is implemented with computer simulation and preferable results are obtained.

  12. Aircraft systems design methodology and dispatch reliability prediction

    OpenAIRE

    Bineid, Mansour

    2005-01-01

    Aircraft despatch reliability was the main subject of this research in the wider content of aircraft reliability. The factors effecting dispatch reliability, aircraft delay, causes of aircraft delays, and aircraft delay costs and magnitudes were examined. Delay cost elements and aircraft delay scenarios were also studied. It concluded that aircraft dispatch reliability is affected by technical and non-technical factors, and that the former are under the designer's control. It showed that ...

  13. Cosmic Rays with Portable Geiger Counters: From Sea Level to Airplane Cruise Altitudes

    Science.gov (United States)

    Blanco, Francesco; La Rocca, Paola; Riggi, Francesco

    2009-01-01

    Cosmic ray count rates with a set of portable Geiger counters were measured at different altitudes on the way to a mountain top and aboard an aircraft, between sea level and cruise altitude. Basic measurements may constitute an educational activity even with high school teams. For the understanding of the results obtained, simulations of extensive…

  14. Delayed appearance of high altitude retinal hemorrhages.

    Directory of Open Access Journals (Sweden)

    Daniel Barthelmes

    Full Text Available BACKGROUND: Retinal hemorrhages have been described as a component of high altitude retinopathy (HAR in association with altitude illness. In this prospective high altitude study, we aimed to gain new insights into the pathophysiology of HAR and explored whether HAR could be a valid early indicator of altitude illness. METHODOLOGY/PRINCIPAL FINDINGS: 28 mountaineers were randomly assigned to two ascent profiles during a research expedition to Mt. Muztagh Ata (7546 m/24,751 ft. Digital fundus photographs were taken prior to expedition at 490 m (1,607 ft, during expedition at 4497 m (14,750 ft = base camp, 5533 m (18,148 ft, 6265 m (20,549 ft, 6865 m (22,517 ft and 4.5 months thereafter at 490 m. Number, size and time of occurrence of hemorrhages were recorded. Oxygen saturation (SpO₂ and hematocrit were also assessed. 79% of all climbers exhibited retinal hemorrhages during the expedition. Number and area of retinal bleeding increased moderately to medium altitudes (6265 m. Most retinal hemorrhages were detected after return to base camp from a high altitude. No post-expeditional ophthalmic sequelae were detected. Significant negative (SpO₂ Beta: -0.4, p<0.001 and positive (hematocrit Beta: 0.2, p = 0.002, time at altitude Beta: 0.33, p = 0.003 correlations with hemorrhages were found. CONCLUSIONS/SIGNIFICANCE: When closely examined, a very large amount of climbers exhibit retinal hemorrhages during exposure to high altitudes. The incidence of retinal hemorrhages may be greater than previously appreciated as a definite time lag was observed between highest altitude reached and development of retinal bleeding. Retinal hemorrhages should not be considered warning signs of impending severe altitude illness due to their delayed appearance.

  15. Endurance training at altitude.

    Science.gov (United States)

    Saunders, Philo U; Pyne, David B; Gore, Christopher J

    2009-01-01

    Since the 1968 Olympic Games when the effects of altitude on endurance performance became evident, moderate altitude training ( approximately 2000 to 3000 m) has become popular to improve competition performance both at altitude and sea level. When endurance athletes are exposed acutely to moderate altitude, a number of physiological responses occur that can comprise performance at altitude; these include increased ventilation, increased heart rate, decreased stroke volume, reduced plasma volume, and lower maximal aerobic power ((.)Vo(2max)) by approximately 15% to 20%. Over a period of several weeks, one primary acclimatization response is an increase in the volume of red blood cells and consequently of (.)Vo(2max). Altitudes > approximately 2000 m for >3 weeks and adequate iron stores are required to elicit these responses. However, the primacy of more red blood cells for superior sea-level performance is not clear-cut since the best endurance athletes in the world, from Ethiopia (approximately 2000 to 3000 m), have only marginally elevated hemoglobin concentrations. The substantial reduction in (.)Vo(2max) of athletes at moderate altitude implies that their training should include adequate short-duration (approximately 1 to 2 min), high-intensity efforts with long recoveries to avoid a reduction in race-specific fitness. At the elite level, athlete performance is not dependent solely on (.)Vo(2max), and the "smallest worthwhile change" in performance for improving race results is as little as 0.5%. Consequently, contemporary statistical approaches that utilize the concept of the smallest worthwhile change are likely to be more appropriate than conventional statistical methods when attempting to understand the potential benefits and mechanisms of altitude training. PMID:19519223

  16. High Altitude and Heart

    OpenAIRE

    Murat Yalcin; Ejder Kardesoglu; Zafer Isilak

    2011-01-01

    Nowadays, situations associated with high altitude such as mountaineering, aviation increasingly draw the attention of people. Gas pressure decreases and hypoxia is encountered when climbing higher. Physiological and pathological responses of human body to different heights are different. Therefore, physiological and pathological changes that may occur together with height and to know the clinical outcomes of these are important . Acute mountain sickness caused by high altitude and high altit...

  17. Aircraft Noise

    Science.gov (United States)

    Michel, Ulf; Dobrzynski, Werner; Splettstoesser, Wolf; Delfs, Jan; Isermann, Ullrich; Obermeier, Frank

    Aircraft industry is exposed to increasing public pressure aiming at a continuing reduction of aircraft noise levels. This is necessary to both compensate for the detrimental effect on noise of the expected increase in air traffic and improve the quality of living in residential areas around airports.

  18. Aircraft Design

    Science.gov (United States)

    Bowers, Albion H. (Inventor); Uden, Edward (Inventor)

    2016-01-01

    The present invention is an aircraft wing design that creates a bell shaped span load, which results in a negative induced drag (induced thrust) on the outer portion of the wing; such a design obviates the need for rudder control of an aircraft.

  19. Sensitivity of two-dimensional model predictions of ozone response to stratospheric aircraft: An update

    Energy Technology Data Exchange (ETDEWEB)

    Considine, D.B.; Douglass, A.R.; Jackman, C.H. [Applied Research Corp., Landover, MD (United States)]|[NASA, Goddard Space Flight Center, Greenbelt, MD (United States)

    1995-02-01

    The Goddard Space Flight Center (GSFC) two-dimensional model of stratospheric photochemistry and dynamics has been used to calculate the O3 response to stratospheric aircraft (high-speed civil transport (HSCT)) emissions. The sensitivity of the model O3 response was examined for systematic variations of five parameters and two reaction rates over a wide range, expanding on calculations by various modeling groups for the NASA High Speed Research Program and the World Meteorological Organization. In all, 448 model runs were required to test the effects of variations in the latitude, altitude, and magnetitude of the aircraft emissions perturbation, the background chlorine levels, the background sulfate aerosol surface area densities, and the rates of two key reactions. No deviation from previous conclusions concerning the response of O3 to HSCTs was found in this more exhaustive exploration of parameter space. Maximum O3 depletions occur for high-altitude, low altitude HSCT perturbations. Small increases in global total O3 can occur for low-altitude, high-altitude injections. Decreasing aerosol surface area densities and background chlorine levels increases the sensitivity of model O3 to the HSCT perturbations. The location of the aircraft emissions is the most important determinant of the model response. Response to the location of the HSCT emissions is not changed qualitatively by changes in background chlorine and aerosol loading. The response is also not very sensitive to changes in the rates of the reactions NO + HO2 yields NO2 + OH and HO2 + O3 yields OH + 2O2 over the limits of their respective uncertainties. Finally, levels of lower stratospheric HO(sub x) generally decrease when the HSCT perturbation is included, even though there are large increases in H2O due to the perturbation.

  20. D-558-2 Aircraft on lakebed

    Science.gov (United States)

    1955-01-01

    . In the process, during August of 1949 they encountered pitch-up problems, which NACA engineers recognized as serious because they could produce a limiting and dangerous restriction on flight performance. Hence, they determined to make a complete investigation of the problem. In 1950, Douglas replaced the turbojet with an LR-8 rocket engine, and its pilot, William B. Bridgeman, flew the aircraft seven times up to a speed of Mach 1.88 (1.88 times the speed of sound) and an altitude of 79,494 feet (the latter an unofficial world's altitude record at the time, achieved on August 15, 1951). In the rocket configuration, a Navy P2B (Navy version of the B-29) launched the airplane at approximately 30,000 feet after taking off from the ground with the Skyrocket attached beneath its bomb bay. During Bridgeman's supersonic flights, he encountered a violent rolling motion known as lateral instability that was less pronounced on the Mach 1.88 flight on August 7, 1951, than on a Mach 1.85 flight in June when he pushed over to a low angle of attack (angle of the fuselage or wing to the prevailing wind direction). The NACA engineers studied the behavior of the aircraft before beginning their own flight research in the airplane in September 1951. Over the next couple of years, NACA pilot A. Scott Crossfield flew the airplane 20 times to gather data on longitudinal and lateral stability and control, wing and tail loads, and lift, drag, and buffeting characteristics at speeds up to Mach 1.878. At that point, Marine Lt. Col. Marion Carl flew the airplane to a new (unofficial) altitude record of 83,235 feet on August 21, 1953, and to a maximum speed of Mach 1.728. Following Carl's completion of these flights for the Navy, NACA technicians at the High-Speed Flight Research Station (HSFRS) near Mojave, Calif., outfitted the LR-8 engine's cylinders with nozzle extensions to prevent the exhaust gas from affecting the rudders at supersonic speeds. This addition also increased the engine

  1. Python Engine Installed in Altitude Wind Tunnel

    Science.gov (United States)

    1949-01-01

    An engine mechanic checks instrumentation prior to an investigation of engine operating characteristics and thrust control of a large turboprop engine with counter-rotating propellers under high-altitude flight conditions in the 20-foot-dianieter test section of the Altitude Wind Tunnel at the Lewis Flight Propulsion Laboratory of the National Advisory Committee for Aeronautics, Cleveland, Ohio, now known as the John H. Glenn Research Center at Lewis Field.

  2. Scaled Model Technology for Flight Research of General Aviation Aircraft Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Our proposed future Phase II activities are aimed at developing a scientifically based "tool box" for flight research using scaled models. These tools will be of...

  3. High Altitude and Heart

    Directory of Open Access Journals (Sweden)

    Murat Yalcin

    2011-04-01

    Full Text Available Nowadays, situations associated with high altitude such as mountaineering, aviation increasingly draw the attention of people. Gas pressure decreases and hypoxia is encountered when climbing higher. Physiological and pathological responses of human body to different heights are different. Therefore, physiological and pathological changes that may occur together with height and to know the clinical outcomes of these are important . Acute mountain sickness caused by high altitude and high altitude cerebral edema are preventable diseases with appropriate precautions. Atmospheric oxygen decreasing with height, initiates many adaptive mechanisms. These adaptation mechanisms and acclimatization vary widely among individuals because of reasons such as environmental factors, exercise and cold. High altitude causes different changes in the cardiovascular system with various mechanisms. Although normal individuals easily adapt to these changes, this situation can lead to undesirable results in people with heart disease. For this reason, it should be known the effective evaluation of the people with known heart disease before traveling to high altitude and the complications due to the changes with height and the recommendations can be made to these patients. [TAF Prev Med Bull 2011; 10(2.000: 211-222

  4. Airborne measurements of CO2 and CH4 onboard the UK FAAM research aircraft using a, Los Gatos Research Inc, cavity enhanced absorption spectrometer

    Science.gov (United States)

    O'Shea, S.; Bauguitte, S.; Muller, J. B.; Le Breton, M.; Gallagher, M. W.; Allen, G.; Percival, C. J.

    2012-12-01

    Airborne measurements of CO2 and CH4 have been made using the UK Facility for Airborne Atmospheric Measurements (FAAM) BAe-146 research aircraft since spring 2011.The measurement system uses a commercially available analyser, based on the off-axis integrated cavity output spectroscopy technique, from Los Gatos Research Inc (FGGA, Model RMT-200). During the first year of operation (29 flights), 1 Hz measurements were found to be accurate to 0.07 ± 2.48ppbv for CH4 and -0.06± 0.66ppmv for CO2. In summer 2011, as part of the BORTAS project (Quantifying the impact of BOReal forest fires on Tropospheric oxidants over the Atlantic using Aircraft and Satellites), outflow from boreal forest fires was measured in Eastern Canada. A number of fresh and photochemically-aged plumes were identified using simultaneous HCN measurements, a widely used tracer for biomass burning. In the freshest plumes, strong relationships were found between CH4, CO2 and other tracers for biomass burning. From this we were able to estimate that 6.9±0.8 g of CH4 and 1551±213 g of CO2 were released into the atmosphere per kg of dry matter burnt. These emission factors are in good agreement with estimates from previous studies in boreal regions. However for aged plumes the correlations between CH4 and other biomass burning tracers were not as robust, most likely due to mixing from other CH4 emission sources, such as the wetland regions. The role of additional emission sources will be investigated using the UK Met Office NAME atmospheric dispersion model and the HYSPLIT trajectory model. Using tailored back trajectory analysis, we will present an interpretation of this new dataset in the context of air mass/fire origin, relating this to MODIS fire maps and source strength.

  5. Problems and Countermeasures in Advanced Research Projects for Civil Aircraft Technology%民用飞机预研项目存在问题及对策

    Institute of Scientific and Technical Information of China (English)

    舒秀丽

    2015-01-01

    In this paper, three common problems are pointed out and dissected in advanced research projects for civil aircraft technology in China and three corresponding countermeasures being successfully implemented are pro-posed. These countermeasures are:establishment and application of innovation information repository supporting the setting-up of advanced research projects to reflect correct demand traction, effective formation and operation of the Integrated Project Team for effective project implementation and enhanced Technology Readiness Assessment promo-ting the application of research achievements. Good results of the application of the above-mentioned countermeas-ures are being achieved in the setting-up and implementation of three "serialized" advanced civil aircraft cockpit technology research projects, which break through the bottleneck of the advanced researches' leading and support-ing role to civil aircraft product development and provide a reference to advanced research projects in other indus-tries as well as in different civil aircraft technical fields.%指出我国民用飞机预研项目常见的三类问题并加以剖析,相应提出三项对策付诸实践:建创新信息库助正确需求牵引,组综合项目团队( IPT)助预研高效实施,抓技术成熟度评估( TRA)促研究成果应用. 上述对策在民用飞机驾驶舱技术领域三个系列化预研项目的立项和实施中显现成效,突破制约民用飞机预研引领和支撑民用飞机产品研发的瓶颈,可供民用飞机各技术领域和其他产业的预研项目借鉴.

  6. Start Up Research Effort in Fluid Mechanics. Advanced Methods for Acoustic and Thrust Benefits for Aircraft Engine Nozzle

    Science.gov (United States)

    White, Samuel G.; Gilinsky, Mikhail M.

    1997-01-01

    In accordance with the project plan for the report period in the proposal titled above, HU and FML teams investigated two sets of concepts for reduction of noise and improvement in efficiency for jet exhaust nozzles of aircraft engines and screws for mixers, fans, propellers and boats. The main achievements in the report period are: (a) Publication of the paper in the AIAA Journal, which described our concepts and some results. (b) The Award in the Civil Research and Development Foundation (CRDF) competition. This 2 year grant for Hampton University (HU) and Central AeroHydrodynamic Institute (TSAGI, Moscow, Russia) supports the research implementation under the current NASA FAR grant. (c) Selection for funding by NASA HQ review panel of the Partnership Awards Concept Paper. This two year grant also will support our current FAR grant. (d) Publication of a Mobius Strip concept in NASA Technical Briefs, June, 1996, and a great interest of many industrial companies in this invention. Successful experimental results with the Mobius shaped screw for mixers, which save more than 30% of the electric power by comparison with the standard screws. Creation of the scientific-popular video-film which can be used for commercial and educational purposes. (e) Organization work, joint meetings and discussions of the NASA LARC JNL Team and HU professors and administration for the solution of actual problems and effective work of the Fluid Mechanics Laboratory at Hampton University. In this report the main designs are enumerated. It also contains for both concept sets: (1) the statement of the problem for each design, some results, publications, inventions, patents, our vision for continuation of this research, and (2) present and expected problems in the future.

  7. Aircraft Data Acquisition

    Directory of Open Access Journals (Sweden)

    Elena BALMUS

    2016-03-01

    Full Text Available The introduction of digital systems instead of analog ones has created a major separation in the aviation technology. Although the digital equipment made possible that the increasingly faster controllers take over, we should say that the real world remains essentially analogue [4]. Fly-by-wire designers attempting to control and measure the real feedback of an aircraft were forced to find a way to connect the analogue environment to their digital equipment. In order to manage the implications of this division in aviation, data optimization and comparison has been quite an important task. The interest in using data acquisition boards is being driven by the technology and design standards in the new generation of aircraft and the ongoing efforts of reducing weight and, in some cases addressing the safety risks. This paper presents a sum of technical report data from post processing and diversification of data acquisition from Arinc 429 interface on a research aircraft platform. Arinc 429 is by far the most common data bus in use on civil transport aircraft, regional jets and executive business jets today. Since its introduction on the Boeing 757/767 and Airbus aircraft in the early 1980s hardly any aircraft has been produced without the use of this data bus. It was used widely by the air transport indu

  8. Research on Lightning Attachment Points Simulation for Aircraft%飞行器雷击附着点数值仿真研究

    Institute of Scientific and Technical Information of China (English)

    赵玉龙; 刘光斌; 余志勇

    2012-01-01

    雷击直接威胁飞行器的飞行安全,基于深入研究雷电电磁脉冲(LEMP)对飞行器的雷击特性,提高飞行器雷电防护性能的目的。文章应用一种静电场分析的方法,利用CST电磁仿真软件的EM工作室对某飞行器的等比例模型进行了雷击附着点的仿真研究,并详细讨论了放电间隙尺寸、雷击方位等相关参数的选择对飞行器闪电分区的影响,通过数值仿真的结果完成了对飞行器的闪电分区并与SAE-ARP5416标准分区进行对比,证明该方法是可行的,结论对该飞行器的雷电防护设计有重要的参考价值。%The lightning is threatening to the safety of flying aircrafts. Based on the purpose of doing research on LEMP characteristic for aircrafts deeply, improving the capability of aircraft LEMP protection. This paper apply a method of electrostatic analysis, doing simulation research on lightning attachment point for a isometrical model of aircraft by the EM studio of CST electromagnetism simulation software. The factors that influence lightning subarea results such as the gap spac- ing, discharging polar have been discussed detail, and accomplish lightning subarea through the numerical simulation result and make comparison to the SAE-ARP5416 standard of lightning subarea, proving this method is viable, so the result have a important reference value for this aircraft lightning protection design.

  9. Probing Aircraft Flight Test Hazard Mitigation for the Alternative Fuel Effects on Contrails & Cruise Emissions (ACCESS) Research Team

    Science.gov (United States)

    Kelly, Michael J.

    2013-01-01

    The Alternative Fuel Effects on Contrails & Cruise Emissions (ACCESS) Project Integration Manager requested in July 2012 that the NASA Engineering and Safety Center (NESC) form a team to independently assess aircraft structural failure hazards associated with the ACCESS experiment and to identify potential flight test hazard mitigations to ensure flight safety. The ACCESS Project Integration Manager subsequently requested that the assessment scope be focused predominantly on structural failure risks to the aircraft empennage raft empennage.

  10. Weed detection using unmanned aircraft vehicles

    Directory of Open Access Journals (Sweden)

    Pflanz, Michael

    2014-03-01

    Full Text Available In contrast to agricultural remote sensing technologies, which are based on images from satellites or manned aircrafts, photogrammetry at low altitude from unmanned aircraft vehicles lead to higher spatial resolution, real-time processing and lower costs. Moreover multicopter aircrafts are suitable vehicles to perform precise path or stationary flights. In terms of vegetation photogrammetry this minimises motion blur and provide better image overlapping for stitching and mapping procedures. Through improved image analyses and through the recent increase in the availability of powerful batteries, microcontrollers and multispectral cameras, it can be expected in future that spatial mapping of weeds from low altitudes will be promoted. A small unmanned aircraft vehicle with a modified RGB camera was tested taking images from agricultural fields. A microcopter with six rotors was applied. The hexacopter in particular is GPS controlled and operates within predefined areas at given altitudes (from 5 to 10 m. Different scenarios of photogrammetrically weed detection have been carried out regarding to variable altitude, image resolution, weed and crop growth stages. First experiences with microcopter showed a high potential for site-specific weed control. Images analyses with regards to recognition of weed patches can be used to adapt herbicide applications to varying weed occurrence across a field.

  11. Chemiluminescent methods and instruments for monitoring of the atmosphere and satellite validation on board of research aircrafts and unmanned aerial vehicles

    Science.gov (United States)

    Sitnikov, Nikolay; Borisov, Yuriy; Akmulin, Dimitry; Chekulaev, Igor; Sitnikova, Vera; Ulanovsky, Alexey; Sokolov, Alexey

    The results of development of instruments based on heterophase chemiluminescence for measurements of space distribution of ozone and nitrogen oxides concentrations on board of research aircrafts and unmanned aerial vehicles carried out in Central Aerological Observatory are presented. Some results of atmospheric investigations on board of research aircrafts M55 “Geophysica” (Russia) and “Falcon” (Germany) carried out using developed instruments in frame of international projects are demonstrated. Small and low power instruments based on chemiluminescent principle for UAV are developed. The results of measurements on board of UAV are shown. The development can be used for satellite data validation, as well as operative environmental monitoring of contaminated areas in particular, chemical plants, natural and industrial disasters territories, areas and facilities for space purposes etc.

  12. Low altitude remote sensing

    NARCIS (Netherlands)

    Pérez Calero, D.; Peyaud, A.; Van der Wal, D.; van 't Hof, J.; Hakkesteegt, H.; Vink, R.; Bovenkamp, E.G.P.; van Antwerpen, G.; Meynart, R.; Neeck, S.P.; Shimoda, H.; Habib, S.

    2008-01-01

    In 2007 TNO started to fly some sensors on an unmanned helicopter platform. These sensors included RGB, B/W and thermal infrared cameras. In 2008 a spectrometer was added. The goal for 2010 is to be able to offer a low altitude flying platform including several sensors. Development of these sensors

  13. An evaluation of the performance of chemistry transport models by comparison with research aircraft observations. Part 1: Concepts and overall model performance

    OpenAIRE

    Brunner, D.; Staehelin, J; Rogers, H. L.; Köhler, M. O.; Pyle, J.A.; Hauglustaine, D.; Jourdain, L.; Berntsen, T. K.; Gauss, M.; I. S. A. Isaksen; MEIJER E.; Van Velthoven, P.; Pitari, G.; Mancini, E; Grewe, G.

    2003-01-01

    A rigorous evaluation of five global Chemistry-Transport and two Chemistry-Climate Models operated by several different groups in Europe, was performed. Comparisons were made of the models with trace gas observations from a number of research aircraft measurement campaigns during the four-year period 1995-1998. Whenever possible the models were run over the same four-year period and at each simulation time step the instantaneous tracer fields were interpolated to all coinciding observati...

  14. An evaluation of the performance of chemistry transport models by comparison with research aircraft observations. Part 1: Concepts and overall model performance

    OpenAIRE

    Brunner, D.; Staehelin, J; Rogers, H. L.; Köhler, M. O.; Pyle, J.A.; Hauglustaine, D.; Jourdain, L.; Berntsen, T. K.; Gauss, M.; I. S. A. Isaksen; MEIJER E.; Van Velthoven, P.; Pitari, G.; Mancini, E; Grewe, V

    2003-01-01

    A rigorous evaluation of five global Chemistry-Transport and two Chemistry-Climate Models operated by several different groups in Europe was performed by comparing the models with trace gas observations from a number of research aircraft measurement campaigns. Whenever possible the models were run over the four-year period 1995–1998 and at each simulation time step the instantaneous tracer fields were interpolated to all coinciding observation points. This approach allows for a ...

  15. An evaluation of the performance of chemistry transport models by comparison with research aircraft observations. Part 1: Concepts and overall model performance

    OpenAIRE

    Brunner, D.; Staehelin, J; Rogers, H. L.; Köhler, M. O.; Pyle, J.A.; Hauglustaine, D.; Jourdain, L.; Berntsen, T. K.; Gauss, M.; I. S. A. Isaksen; MEIJER E.; Van Velthoven, P.; Pitari, G.; Mancini, E; Grewe, V

    2003-01-01

    International audience A rigorous evaluation of five global Chemistry-Transport and two Chemistry-Climate Models operated by several different groups in Europe was performed by comparing the models with trace gas observations from a number of research aircraft measurement campaigns. Whenever possible the models were run over the four-year period 1995–1998 and at each simulation time step the instantaneous tracer fields were interpolated to all coinciding observation points. This approach a...

  16. An evaluation of the performance of chemistry transport models by comparison with research aircraft observations. Part 1: Concepts and overall model performance

    OpenAIRE

    Brunner, D.; Staehelin, J; Rogers, H. L.; Köhler, M. O.; Pyle, J.A.; Hauglustaine, D.; Jourdain, L.; Berntsen, T. K.; Gauss, M.; I. S. A. Isaksen; MEIJER E.; Van Velthoven, P.; Pitari, G.; Mancini, E; Grewe, G.

    2003-01-01

    International audience A rigorous evaluation of five global Chemistry-Transport and two Chemistry-Climate Models operated by several different groups in Europe, was performed. Comparisons were made of the models with trace gas observations from a number of research aircraft measurement campaigns during the four-year period 1995-1998. Whenever possible the models were run over the same four-year period and at each simulation time step the instantaneous tracer fields were interpolated to all...

  17. An evaluation of the performance of chemistry transport models by comparison with research aircraft observations. Part 1: Concepts and overall model performance

    OpenAIRE

    Brunner, D.; Staehelin, J; Rogers, H. L.; Köhler, M. O.; Pyle, J.A.; Hauglustaine, D.; Jourdain, L.; Berntsen, T. K.; Gauss, M.; I. S. A. Isaksen; MEIJER E.; Van Velthoven, P.; Pitari, G.; Mancini, E; Grewe, G.

    2003-01-01

    A rigorous evaluation of five global Chemistry-Transport and two Chemistry-Climate Models operated by several different groups in Europe, was performed. Comparisons were made of the models with trace gas observations from a number of research aircraft measurement campaigns during the four-year period 1995-1998. Whenever possible the models were run over the same four-year period and at each simulation time step the instantaneous tracer fields were interpol...

  18. Research on the Effects of Fatigue within the Corporate/Business Aircraft Environment

    Science.gov (United States)

    Neri, David F.; Rosekind, Mark R.; Co, Elizabeth L.; Gregory, Kevin B.; Miller, Donna L.

    1997-01-01

    In 1980, responding to a Congressional request, NASA Ames Research Center created a program to examine whether 'there is a safety problem of uncertain magnitude, due to transmeridian flying and a potential problem due to fatigue in association with various factors found in air transport operations.' The NASA Ames Fatigue/Jet Lag Program was created to collect systematic, scientific information on fatigue, sleep, circadian rhythms, and performance in flight operations. Three Program goals were established and continue to guide research efforts to: (1) determine the extent of fatigue, sleep loss, and circadian disruption in flight operations; (2) determine the impact of these factors on flight crew performance; (3) develop and evaluate countermeasures to mitigate the adverse effects of these factors and maximize flight crew performance and alertness. Since 1980, studies have been conducted in a variety of aviation environments, in controlled laboratory environments, as well as in a full-mission flight simulation. Early studies included investigations of short-haul, long-haul, and overnight cargo flight crews. In 1991, the name of the program was changed to the Fatigue Countermeasures Program to provide a greater emphasis on the development and evaluation of countermeasures. More recent work has examined the effects of planned cockpit rest as an operational countermeasure and provided analyses of the pertinent sleep/duty factors preceding an aviation accident at Guantanamo Bay, Cuba. The Short-Haul study examined the extent of sleep loss, circadian disruption, and fatigue engendered by flying commercial short-haul air transport operations (flight legs less than eight hours). This was one of the first field studies conducted by the NASA program and provided unique insight into the physiological and subjective effects of flying commercial short-haul operations. It demonstrated that a range of measures could be obtained in an operational environment without disturbing

  19. Modelling and Analysis of a Regenerative Fuel Cell Propulsion System for a High Altitude Long Endurance UAV

    Science.gov (United States)

    Simpson, Mike B.

    2004-01-01

    In the search to bridge current gaps in surveillance and communication technologies, a new type of, aircraft is currently undergoing design. The idea of a High Altitude Long Endurance (HALE) aircraft is already a few decades old, but has only recently become realizable. A relay and collector of information at altitudes of 65,000 feet and higher could greatly improve standards of data exchange, homeland security, and research of the air, land and sea. NASA, as a major force in propulsion research, is exploring methods of powering an autonomous aircraft for days, weeks, or even months without refueling. Such a task requires not only high energy density, but also the ability to make use of renewable energy sources to regenerate power. Hydrogen is one of the most energy dense fuels available. Fuel cells make use of hydrogen by harnessing the energy released as it combines with oxygen to produce electricity and water. Fuel cells are envisioned to occupy future propulsion systems in cooperation with solar cells where the photovoltaic arrays harness sunlight into power which can electrolize the water byproduct into reusable hydrogen and oxygen. Modeling this type of system requires adequate assumptions of support hardware and daily transients in operation. The performance of a regenerative fuel cell propulsion system lies in the flight characteristics (altitude, density, temperature, latitude, etc.). Each subsystem is defined by many parameters which can be varied across wide ranges. Statistical and probabilistic analyses bring forward a wealth of information that can be utilized in the design process. This is necessary since the required technologies are relatively young and barely, if yet, capable. Once the modeling is complete, a design space exploration of this highly constrained scenario can be utilized to find the optimal design. The model will become an interactive environment with which experiments and tests can be run. When linked

  20. Research on Aircraft Noise Evaluation System%飞机噪声评价体系研究

    Institute of Scientific and Technical Information of China (English)

    沈颖; 谢实海; 陈荣生

    2000-01-01

    The evaluation system of aircraft noise and environment noise should be integrated,because aircraft noise belongs to environment noise.At the same time,there should be some difference in the evaluation system of aircraft noise.For solving this contradiction,this article puts forward a new evaluation system of aircraft noise.This new system unifies the evaluation of aircraft noise and other environment noise effectively,and adds a new evaluation index single-event noise exposure level.The system not only considers the characteristics of aircraft noise,which is different from other traffic noise,but also adds aircraft noise to other traffic noise,which can reflect sound environment around airport really.This system has practical worthiness and theory significance.%飞机噪声的共性决定其评价体系应于环境噪声评价体系统一,而飞机噪声的个性决定其评价方法必须有别于一般环境噪声评价.本文通过对飞机噪声的共性与个性的分析,建立了一种新的飞机噪声评价体系,它不仅考虑到飞机噪声不同于其他交通噪声的特点,而且有效地统一了飞机噪声与城市区域环境噪声的评价体系.新体系可以将机场周围飞机噪声与其他交通噪声叠加,真实地反映机场周围声环境,具有一定的实用价值和理论指导意义.

  1. Overall design of imaging spectrometer on-board light aircraft

    Energy Technology Data Exchange (ETDEWEB)

    Zhongqi, H.; Zhengkui, C.; Changhua, C.

    1996-11-01

    Aerial remote sensing is the earliest remote sensing technical system and has gotten rapid development in recent years. The development of aerial remote sensing was dominated by high to medium altitude platform in the past, and now it is characterized by the diversity platform including planes of high-medium-low flying altitude, helicopter, airship, remotely controlled airplane, glider, and balloon. The widely used and rapidly developed platform recently is light aircraft. Early in the close of 1970s, Beijing Research Institute of Uranium Geology began aerial photography and geophysical survey using light aircraft, and put forward the overall design scheme of light aircraft imaging spectral application system (LAISAS) in 19905. LAISAS is comprised of four subsystem. They are called measuring platform, data acquiring subsystem, ground testing and data processing subsystem respectively. The principal instruments of LAISAS include measuring platform controlled by inertia gyroscope, aerial spectrometer with high spectral resolution, imaging spectrometer, 3-channel scanner, 128-channel imaging spectrometer, GPS, illuminance-meter, and devices for atmospheric parameters measuring, ground testing, data correction and processing. LAISAS has the features of integrity from data acquisition to data processing and to application; of stability which guarantees the image quality and is comprised of measuring, ground testing device, and in-door data correction system; of exemplariness of integrated the technology of GIS, GPS, and Image Processing System; of practicality which embodied LAISAS with flexibility and high ratio of performance to cost. So, it can be used in the fields of fundamental research of Remote Sensing and large-scale mapping for resource exploration, environmental monitoring, calamity prediction, and military purpose.

  2. Altitude Effects on Thermal Ice Protection System Performance; a Study of an Alternative Approach

    Science.gov (United States)

    Addy, Harold E., Jr.; Orchard, David; Wright, William B.; Oleskiw, Myron

    2016-01-01

    Research has been conducted to better understand the phenomena involved during operation of an aircraft's thermal ice protection system under running wet icing conditions. In such situations, supercooled water striking a thermally ice-protected surface does not fully evaporate but runs aft to a location where it freezes. The effects of altitude, in terms of air pressure and density, on the processes involved were of particular interest. Initial study results showed that the altitude effects on heat energy transfer were accurately modeled using existing methods, but water mass transport was not. Based upon those results, a new method to account for altitude effects on thermal ice protection system operation was proposed. The method employs a two-step process where heat energy and mass transport are sequentially matched, linked by matched surface temperatures. While not providing exact matching of heat and mass transport to reference conditions, the method produces a better simulation than other methods. Moreover, it does not rely on the application of empirical correction factors, but instead relies on the straightforward application of the primary physics involved. This report describes the method, shows results of testing the method, and discusses its limitations.

  3. Advanced Aircraft Material

    Directory of Open Access Journals (Sweden)

    Vivek Kumar Prince

    2013-06-01

    Full Text Available There has been long debate on “advanced aircraft material” from past decades & researchers too came out with lots of new advanced material like composites and different aluminum alloys. Now days a new advancement that is in great talk is third generation Aluminum-lithium alloy. Newest Aluminum-lithium alloys are found out to have low density, higher elastic modulus, greater stiffness, greater cryogenic toughness, high resistance to fatigue cracking and improved corrosion resistance properties over the earlier used aircraft material as mentioned in Table 3 [1-5]. Comparison had been made with nowadays used composite material and is found out to be more superior then that

  4. Research into the restoration method for high-altitude piston engine%活塞发动机高空动力恢复方法的探索

    Institute of Scientific and Technical Information of China (English)

    徐斌; 梁郑岳

    2009-01-01

    分析了新一代无人机动力的发展,针对小型无人机的活塞式动力装置的性能特点,提出了一种小型无人机二级增压系统匹配的高空实现方法.并对发动机的高空性能进行了初步分析,验证了方案的可行性,为高空无人机动力装置提供了设计依据.%The power development of a new generation of unmanned aerial vehicle (UAV) was analyzed.According to the performance characteristic of small UAV powered by the piston devices,a method matching small UAV's two-stage supercharging system was designed for realization at high altitude.A preliminary analysis on the high-altitude performance of engine was conducted to verify the feasibility of the programme,providing a design basis for high-altitude UAV.

  5. Follow on Research for Multi-Utility Technology Test Bed Aircraft at NASA Dryden Flight Research Center (FY13 Progress Report)

    Science.gov (United States)

    Pak, Chan-Gi

    2013-01-01

    Modern aircraft employ a significant fraction of their weight in composite materials to reduce weight and improve performance. Aircraft aeroservoelastic models are typically characterized by significant levels of model parameter uncertainty due to the composite manufacturing process. Small modeling errors in the finite element model will eventually induce errors in the structural flexibility and mass, thus propagating into unpredictable errors in the unsteady aerodynamics and the control law design. One of the primary objectives of Multi Utility Technology Test-bed (MUTT) aircraft is the flight demonstration of active flutter suppression, and therefore in this study, the identification of the primary and secondary modes for the structural model tuning based on the flutter analysis of MUTT aircraft. The ground vibration test-validated structural dynamic finite element model of the MUTT aircraft is created in this study. The structural dynamic finite element model of MUTT aircraft is improved using the in-house Multi-disciplinary Design, Analysis, and Optimization tool. In this study, two different weight configurations of MUTT aircraft have been improved simultaneously in a single model tuning procedure.

  6. RESEARCH OF NIGHT LIGHT EFFECTS ON COLORIMETRIC CHARACTERISTICS OF IMAGE PERCEIVED BY THE PILOT IN AN AIRCRAFT COCKPIT

    Directory of Open Access Journals (Sweden)

    I. O. Zharinov

    2015-09-01

    Full Text Available Subject of Research. The influence of radiation spectra from the source of artificial night light on colorimetric characteristics of image perceived by the pilot in the aircraft cockpit has been studied. The image is displayed on the LCD screen of multifunctional color indication equipment unit. Night illumination of the cockpit is performed with the use of artificial lamps of red, green, blue and, rarely, white light. Method. Any given color to be displayed on the screen is perceived by an observer differently with presence and absence of external illumination. When external light of white color is used, perceived color depends upon color temperature of the light source; if illumination source has any arbitrary spectral characteristics, then perceivable color depends upon whole spectral content of the used source. The color, perceived by an observer, is formed as the mixture of the color displayed on the screen (image element color with the color presented by diffuse reflection of external illumination source from the surface of the screen. The brightness of both colors is added. Mathematical expressions, that define calculation rule for chromaticity coordinates of color perceived by an observer, are based on the Grassmann’s law of additive color mixing. Quantitative analysis of the effect, caused by radiation spectra from an external source of artificial light on color gamut area, corresponding to image, perceived by an observer, has been performed through simulation in MathCad 15.0. Main Results. It was shown, that the color palette of on-board indication equipment, obtained on automated working place for any preset source of external illumination of fluorescent spectrum, corresponding to white light, is not usable correctly in the aircraft night flight mode. An observer loses ability to perceive properly saturated primary colors of red and blue in the case of green-blue light source of external illumination; and the same issue occurs with

  7. Mirrors and smoke: A. V. Hill, his Brigands, and the science of anti-aircraft gunnery in World War I.

    Science.gov (United States)

    Van der Kloot, William

    2011-12-20

    In 1916 Captain A. V. Hill was transferred from the infantry to the Ministry of Munitions to work on anti-aircraft gunnery. He determined the three-dimensional coordinates of flying objects by placing two mirrors far apart. The mirrors were viewed from a fixed distance above them and observers simultaneously marked the position of the object. He gathered brilliant men, most too old or too young for conscription, who became known as Hill's Brigands. They determined the coordinates of the explosions of shots fired with different fuse settings and fitted them with the ballistic equations to construct accurate gunnery tables. They solved the puzzle of erratic fuse timing at high altitudes. They developed apparatus to locate aircraft by sound. Travelling groups of Brigands worked with anti-aircraft gunners, which Hill regarded as the dawn of operations research. Hill was as adept at leading scientists as he was at doing science.

  8. Conceptual design, evaluation and research identification for Remote Augmented Propulsive Lift Systems (RALS) with ejectors for VTOL aircraft

    Science.gov (United States)

    Willis, W. S.; Konarski, M.; Sutherland, M. V.

    1982-01-01

    Ejector concepts for use with a remote augmented lift system (RALS) exhaust nozzle were studied. A number of concepts were considered and three were selected as having the greatest promise of providing the desired aircraft and exhaust gas cooling and lift enhancement. A scale model test program is recommended to explore the effects of the more important parameters on ejector performance.

  9. Multi-Domain Modeling and Simulation of an Aircraft System for Advanced Vehicle-Level Reasoning Research and Development

    Directory of Open Access Journals (Sweden)

    : F. Khan

    2014-05-01

    Full Text Available In this paper, we describe a simulation based health monitoring system test-bed for aircraft systems. The purpose of the test-bed is to provide a technology neutral basis for implementing and evaluation of reasoning systems on vehicle level and software architecture in support of the safety and maintenance process. This simulation test-bed will provide the sub-system level results and data which can be fed to the VLRS to generate vehicle level reasoning to achieve broader level diagnoses. This paper describes real-time system architecture and concept of operations for the aircraft major sub-systems. The four main components in the real-time test-bed are the aircraft sub-systems (e.g. battery, fuel, engine, generator, heating and lighting system simulation model, fault insertion unit, health monitoring data processing and user interface. In this paper, we adopted a component based modelling paradigm for the implementation of the virtual aircraft systems. All of the fault injections are currently implemented via software. The fault insertion unit allows for the repeatable injection of faults into the system. The simulation test-bed has been tested with many different faults which were undetected on system level to process and detect on the vehicle level reasoning. This article also shows how one system fault can affect the overall health of the vehicle.

  10. Aircraft cybernetics

    Science.gov (United States)

    1977-01-01

    The use of computers for aircraft control, flight simulation, and inertial navigation is explored. The man-machine relation problem in aviation is addressed. Simple and self-adapting autopilots are described and the assets and liabilities of digital navigation techniques are assessed.

  11. Cerebrovascular stroke at high altitude

    International Nuclear Information System (INIS)

    Objective: To asses the high altitude as a risk factor for cerebrovascular stroke in people residing at a height greater than 15,000 feet above sea level. Results: Ten patients suffered from stroke at high altitude while just one case had stroke in indexed age group at lower heights (p-value<0.05). Relative risk was 10 times greater at high altitude. Conclusion: High altitude is a risk factor for stroke in persons residing at altitudes of over 15, 000 ft. (author)

  12. 空战飞机嵌入式训练系统的研究%Research on Embedded Training System in Combat Aircraft

    Institute of Scientific and Technical Information of China (English)

    亓凯; 杨任农; 左家亮; 黄震宇; 白绢

    2011-01-01

    Air Forces are facing difficulties in training effectively for their combat aircraft. Embedded Training is considered to be a effective solution for this problem. We have researched a new embedded training system of combat aircraft with high-speed wireless net and real-time display and control that combines technologies and experiments in existence. The system can make full use of the intrinsic equipment in combat aircraft, provide the crew a real environment for operating and training. In addition, commanders could watch the training status at the same time and make a scientific evaluation. It did marked training effect.%空军正面对提高空战飞机训练效率的难题,嵌入式训练是解决这个问题的有效途径.结合现有研究技术和经验,研究了拥有高速无线网络和实时显控的嵌入式训练系统.可以使飞行员充分利用飞机内的原有设备进行训练,为飞行员提供了真实的操作、训练环境,同时指挥人员能够实时观察训练状况并做出科学的评估,具有突破性的训练效果.

  13. Neural networks for aircraft control

    Science.gov (United States)

    Linse, Dennis

    1990-01-01

    Current research in Artificial Neural Networks indicates that networks offer some potential advantages in adaptation and fault tolerance. This research is directed at determining the possible applicability of neural networks to aircraft control. The first application will be to aircraft trim. Neural network node characteristics, network topology and operation, neural network learning and example histories using neighboring optimal control with a neural net are discussed.

  14. 海拔高度对计算机散热影响的研究%Research on the Effects of Altitude in Co mputer Heat Dissipation

    Institute of Scientific and Technical Information of China (English)

    黄延平

    2014-01-01

    中国海拔1 km以上地区占全国总面积65%,属于高原国家.计算机等电子设备的散热能力受海拔高度的影响很大,电器的散热的好坏直接影响元器件的寿命、运算速度和使用的稳定性等.为了研究海拔高度对电子设备的散热的影响,依据热力学的基本理论,引入了海拔高度参数,对建立在海平面基础上的茹卡乌斯数学模型、Chilton-Colburn方程等传热计算模型进行了修正,建立了一套不同海拔高度电器热分析计算方法,解决了海拔高度参数和电器散热关系的问题.其分析结果符合国际电工委员会实验标准,并用Ansys.Icepak14.5电子热设计专用软件进行了验证.为不同海拔高度地区计算机等电器设备热设计和寿命评估提供了理论基础.%The areas at an altitude of 1000m and above account for 65% of the total area of China,therefore,China is a plateau country .For electronic devices such as computers,cooling ability is much affected by attitude,and electric heat dissipation directly affects the service life of components,computing speed,stability,etc .To study the effects of altitude on the cooling of elec-tric devices,the altitude parameters are introduced to modify the Zukauskas mathematical model,Chiltion-Colburn model,and other heat transfer models,according to the fundamental theory of thermodynamics .Electrical heat calculation method for the electronic devices at different altitudes is proposed,and the relationship between the altitude and electrical cooling capability is revealed .The analysis result conforms to the international electro-technical commission standard experiment and is verified by the specialized ther-mal design software Ansys.Icepak4.5,which provides theoretical basis for the thermal design and the life-span evaluation of the electric devices,such as computers,at different altitudes .

  15. Stratospheric aircraft: Impact on the stratosphere

    Energy Technology Data Exchange (ETDEWEB)

    Johnston, H.

    1992-02-01

    The steady-state distribution of natural stratospheric ozone is primarily maintained through production by ultraviolet photolysis of molecular oxygen, destruction by a catalytic cycle involving nitrogen oxides (NO{sub x}), and relocation by air motions within the stratosphere. Nitrogen oxides from the exhausts of a commercially viable fleet of supersonic transports would exceed the natural source of stratospheric nitrogen oxides if the t should be equipped with 1990 technology jet engines. This model-free comparison between a vital natural global ingredient and a proposed new industrial product shows that building a large fleet of passenger stratospheric aircraft poses a significant global problem. NASA and aircraft industries have recognized this problem and are studying the redesign of jet aircraft engines in order to reduce the nitrogen oxides emissions. In 1989 atmospheric models identified two other paths by which the ozone destroying effects of stratospheric aircraft might be reduced or eliminated: (1) Use relatively low supersonic Mach numbers and flight altitudes. For a given rate of nitrogen oxides injection into the stratosphere, the calculated reduction of total ozone is a strong function of altitude, and flight altitudes well below 20 kilometers give relatively low calculated ozone reductions. (2) Include heterogeneous chemistry in the two-dimensional model calculations. Necessary conditions for answering the question on the title above are to improve the quality of our understanding of the lower stratosphere and to broaden our knowledge of hetergeneous stratospheric chemistry. This article reviews recently proposed new mechanisms for heterogeneous reactions on the global stratospheric sulfate aerosols.

  16. Stratospheric aircraft: Impact on the stratosphere?

    Energy Technology Data Exchange (ETDEWEB)

    Johnston, H.

    1992-02-01

    The steady-state distribution of natural stratospheric ozone is primarily maintained through production by ultraviolet photolysis of molecular oxygen, destruction by a catalytic cycle involving nitrogen oxides (NO{sub x}), and relocation by air motions within the stratosphere. Nitrogen oxides from the exhausts of a commercially viable fleet of supersonic transports would exceed the natural source of stratospheric nitrogen oxides if the t should be equipped with 1990 technology jet engines. This model-free comparison between a vital natural global ingredient and a proposed new industrial product shows that building a large fleet of passenger stratospheric aircraft poses a significant global problem. NASA and aircraft industries have recognized this problem and are studying the redesign of jet aircraft engines in order to reduce the nitrogen oxides emissions. In 1989 atmospheric models identified two other paths by which the ozone destroying effects of stratospheric aircraft might be reduced or eliminated: (1) Use relatively low supersonic Mach numbers and flight altitudes. For a given rate of nitrogen oxides injection into the stratosphere, the calculated reduction of total ozone is a strong function of altitude, and flight altitudes well below 20 kilometers give relatively low calculated ozone reductions. (2) Include heterogeneous chemistry in the two-dimensional model calculations. Necessary conditions for answering the question on the title above are to improve the quality of our understanding of the lower stratosphere and to broaden our knowledge of hetergeneous stratospheric chemistry. This article reviews recently proposed new mechanisms for heterogeneous reactions on the global stratospheric sulfate aerosols.

  17. Research of Low-altitude Photogrammetry Implementation Strategy of China's Ancient Circumvallation - Project of Surveying and Mapping of Ming Dynasty Circumvallation (Southern Wall Section

    Directory of Open Access Journals (Sweden)

    Yu Yan

    2014-02-01

    Full Text Available Most of the existing ancient circumvallation in China today is in the natural environment and the environment has never been cleaned up. As the blockings caused by the vegetation on the circumvallation itself, the surrounding vegetations, the constructions and other surface features affect the terrestrial laser scanning and the low altitude photogrammetry, there are often incomplete three-dimensional points cloud data. Therefore, in the prior period of conservation works, surveying and mapping are difficult to implement under this circumstance. In this paper, based on the surveying and mapping of ZhengDing Ming Circumvallation and some other ancient circumvallation in northern China, characteristics of Chinese northern ancient circumvallation are summarized in the terms of their structures and spatial arrangements as well as the distribution of natural obstacles, and section paradigm pictures protracted. On the basis of these pictures, distractors of surveying and mapping are classified and fine adjustments are made to each category in aspects such as multiple aerial baseline setting, Unmanned Aerial Vehicle(UAV control and equipment selection, parameter adjustment, ground assistant work, and selection of season, time and weather. The purpose of such adjustments is to get the best possible integrated centimeter level point density surveying and mapping data of the circumvallation so that the goal of optimal application of the technique of UAV low-altitude photogrammetry can be achieved. Ancient circumvallation is the largest stock and most widespread type of architectural heritage in China. At present the surveying and mapping equipment available mainly falls into three categories: terrestrial laser scanning, low altitude photogrammetry and LIDAR. In this project, through analysis of characteristics, and summing-up of rules, optimization of operating method is achieved, high density, high integrity surveying and mapping data under the condition

  18. Systems Design and Experimental Evaluation of a High-Altitude Relight Test Facility

    Science.gov (United States)

    Paxton, Brendan

    Novel advances in gas turbine engine combustor technology, led by endeavors into fuel efficiency and demanding environmental regulations, have been fraught with performance and safety concerns. While the majority of low emissions gas turbine engine combustor technology has been necessary for power generation applications, the push for ultra-low NOx combustion in aircraft jet engines has been ever present. Recent state-of-the-art combustor designs notably tackle historic emissions challenges by operating at fuel-lean conditions, which are characterized by an increase in the amount of air flow sent to the primary combustion zone. While beneficial in reducing NOx emissions, the fuel-lean mechanisms that characterize these combustor designs rely heavily upon high-energy and high-velocity air flows to sufficiently mix and atomize fuel droplets, ultimately leading to flame stability concerns during low-power operation. When operating at high-altitude conditions, these issues are further exacerbated by the presence of low ambient air pressures and temperatures, which can lead to engine flame-out situations and hamper engine relight attempts. To aid academic and industrial research ventures into improving the high-altitude lean blow-out and relight performance of modern gas turbine engine combustor technologies, the High-Altitude Relight Test Facility (HARTF) was designed and constructed at the University of Cincinnati (UC) Combustion and Fire Research Laboratory (CFRL). Following its construction, an experimental evaluation of its abilities to facilitate optically-accessible ignition, combustion, and spray testing for gas turbine engine combustor hardware at simulated high-altitude conditions was performed. In its evaluation, performance limit references were established through testing of the HARTF vacuum and cryogenic air-chilling capabilities. These tests were conducted with regard to end-user control---the creation and the maintenance of a realistic high-altitude

  19. Aircraft Wiring Support Equipment Integration Laboratory (AWSEIL)

    Data.gov (United States)

    Federal Laboratory Consortium — Purpose: The Aircraft Wiring Support Equipment Integration Laboratory (AWSEIL) provides a variety of research, design engineering and prototype fabrication services...

  20. Brain Food at High Altitude.

    Science.gov (United States)

    Jain, Vishal

    2016-01-01

    Scenic view at high altitude is a pleasure to the eyes, but it has some shortcoming effects as well. High altitude can be divided into different categories, i.e., high altitude (3000-5000 ft), very high altitude (5000-8000 ft), and extreme altitude (above 8000 ft). Much of the population resides at high altitude, and others go there for tourism. Military personnel are also posted there to defend boundaries. As we ascent to high altitude, partial pressure of oxygen reduces, whereas concentration remains the same; this reduces the availability of oxygen to different body parts. This pathophysiological condition is known as hypobaric hypoxia (HH) which leads to oxidative stress and further causes cognitive dysfunction in some cases. Hypoxia causes neurodegeneration in different brain regions; however, the hippocampus is found to be more prone in comparison to other brain regions. As the hippocampus is affected most, therefore, spatial memory is impaired most during such condition. This chapter will give a brief review of the damaging effect of high altitude on cognition and also throw light on possible herbal interventions at high altitude, which can improve cognitive performance as well as provide protection against the deteriorating effect of hypobaric hypoxia at high altitude. PMID:27651260

  1. Brain Food at High Altitude.

    Science.gov (United States)

    Jain, Vishal

    2016-01-01

    Scenic view at high altitude is a pleasure to the eyes, but it has some shortcoming effects as well. High altitude can be divided into different categories, i.e., high altitude (3000-5000 ft), very high altitude (5000-8000 ft), and extreme altitude (above 8000 ft). Much of the population resides at high altitude, and others go there for tourism. Military personnel are also posted there to defend boundaries. As we ascent to high altitude, partial pressure of oxygen reduces, whereas concentration remains the same; this reduces the availability of oxygen to different body parts. This pathophysiological condition is known as hypobaric hypoxia (HH) which leads to oxidative stress and further causes cognitive dysfunction in some cases. Hypoxia causes neurodegeneration in different brain regions; however, the hippocampus is found to be more prone in comparison to other brain regions. As the hippocampus is affected most, therefore, spatial memory is impaired most during such condition. This chapter will give a brief review of the damaging effect of high altitude on cognition and also throw light on possible herbal interventions at high altitude, which can improve cognitive performance as well as provide protection against the deteriorating effect of hypobaric hypoxia at high altitude.

  2. LOW ALTITUDE AIRSHIPS FOR SEAMLESS MOBILE COMMUNICATION IN AIR TRAVEL

    Directory of Open Access Journals (Sweden)

    Madhu D

    2014-11-01

    Full Text Available The Aviation Administration policy prohibits the use of mobile phones in Aircraft during transition for the reason it may harm their communication system due to Electromagnetic interference. In case the user wants to access cellular network at higher altitudes, base station access is a problem. Large number of channels are allocated to a single user moving at high speed by various Base Stations in the vicinity to service the request requiring more resources. Low Altitude Platforms (LAPs are provided in the form of Base stations in the Airships with antennas projected upwards which has direct link with the Ground Station. LAPs using LongEndurance Multi-Intelligence Vehicle (LEMVs equipped with an engine for mobility and stable positioning against rough winds are utilized. This paper proposes a system that allows the passengers to use their mobiles in Aircraft using LAPs as an intermediate system between Aircraft and Ground station. As the Aircraft is dynamic, it has to change its link frequently with the Airships, MANETs using AODV protocol is established in the prototype using NS2 to provide the service and the results are encouraging

  3. Factors influencing aircraft ground handling performance

    Science.gov (United States)

    Yager, T. J.

    1983-01-01

    Problems associated with aircraft ground handling operations on wet runways are discussed and major factors which influence tire/runway braking and cornering traction capability are identified including runway characteristics, tire hydroplaning, brake system anomalies, and pilot inputs. Research results from tests with instrumented ground vehicles and aircraft, and aircraft wet runway accident investigation are summarized to indicate the effects of different aircraft, tire, and runway parameters. Several promising means are described for improving tire/runway water drainage capability, brake system efficiency, and pilot training to help optimize aircraft traction performance on wet runways.

  4. Rapid, optical measurement of the atmospheric pressure on a fast research aircraft using open-path TDLAS

    Directory of Open Access Journals (Sweden)

    B. Buchholz

    2014-05-01

    Full Text Available Because of the high travel speed, the complex flow dynamics around an aircraft and the complex dependency of the fluid dynamics on numerous airborne parameters, it is quite difficult to obtain accurate pressure values at a specific instrument location of an aircraft's fuselage. Complex simulations using computational fluid dynamics (CFD models can in theory computationally "transfer" pressure values from one location to another. However, for long flight patterns, this process is inconvenient and cumbersome. Furthermore these CFD transfer models require a local experimental validation, which is rarely available. In this paper, we describe an integrated approach for a spectroscopic, calibration-free, in-flight pressure determination in an open-path White cell on an aircraft fuselage using ambient, atmospheric water vapour as the "sensor species". The presented measurements are realized with the HAI (Hygrometer for Atmospheric Investigations instrument, built for multiphase water detection via calibration-free TDLAS (tunable diode laser absorption spectroscopy. The pressure determination is based on raw data used for H2O concentration measurement, but with a different post-flight evaluation method, and can therefore be conducted at deferred time intervals on any desired flight track. The spectroscopic pressure is compared in-flight with the static ambient pressure of the aircraft avionic system and a micro-mechanical pressure sensor, located next to the open-path cell, over a pressure range from 150 hPa to 800 hPa, and a water vapour concentration range of more than three orders of magnitude. The correlation between the micro-mechanical pressure sensor measurements and the spectroscopic pressure measurements show an average deviation from linearity of only 0.14% and a small offset of 9.5 hPa. For the spectroscopic pressure evaluation we derive measurement uncertainties under laboratory conditions of 3.2% and 5.1% during in flight operation on the

  5. Impact of aircraft systems within aircraft operation: A MEA trajectory optimisation study

    OpenAIRE

    Seresinhe, R.

    2014-01-01

    Air transport has been a key component of the socio-economic globalisation. The ever increasing demand for air travel and air transport is a testament to the success of the aircraft. But this growing demand presents many challenges. One of which is the environmental impact due to aviation. The scope of the environmental impact of aircraft can be discussed from many viewpoints. This research focuses on the environmental impact due to aircraft operation. Aircraft operation causes...

  6. Aircraft noise prediction

    Science.gov (United States)

    Filippone, Antonio

    2014-07-01

    This contribution addresses the state-of-the-art in the field of aircraft noise prediction, simulation and minimisation. The point of view taken in this context is that of comprehensive models that couple the various aircraft systems with the acoustic sources, the propagation and the flight trajectories. After an exhaustive review of the present predictive technologies in the relevant fields (airframe, propulsion, propagation, aircraft operations, trajectory optimisation), the paper addresses items for further research and development. Examples are shown for several airplanes, including the Airbus A319-100 (CFM engines), the Bombardier Dash8-Q400 (PW150 engines, Dowty R408 propellers) and the Boeing B737-800 (CFM engines). Predictions are done with the flight mechanics code FLIGHT. The transfer function between flight mechanics and the noise prediction is discussed in some details, along with the numerical procedures for validation and verification. Some code-to-code comparisons are shown. It is contended that the field of aircraft noise prediction has not yet reached a sufficient level of maturity. In particular, some parametric effects cannot be investigated, issues of accuracy are not currently addressed, and validation standards are still lacking.

  7. Recent advance in nonlinear aeroelastic analysis and control of the aircraft

    Institute of Scientific and Technical Information of China (English)

    Xiang Jinwu; Yan Yongju; Li Daochun

    2014-01-01

    A review on the recent advance in nonlinear aeroelasticity of the aircraft is presented in this paper. The nonlinear aeroelastic problems are divided into three types based on different research objects, namely the two dimensional airfoil, the wing, and the full aircraft. Different non-linearities encountered in aeroelastic systems are discussed firstly, where the emphases is placed on new nonlinear model to describe tested nonlinear relationship. Research techniques, especially new theoretical methods and aeroelastic flutter control methods are investigated in detail. The route to chaos and the cause of chaotic motion of two-dimensional aeroelastic system are summarized. Var-ious structural modeling methods for the high-aspect-ratio wing with geometric nonlinearity are dis-cussed. Accordingly, aerodynamic modeling approaches have been developed for the aeroelastic modeling of nonlinear high-aspect-ratio wings. Nonlinear aeroelasticity about high-altitude long-endurance (HALE) and fight aircrafts are studied separately. Finally, conclusions and the chal-lenges of the development in nonlinear aeroelasticity are concluded. Nonlinear aeroelastic problems of morphing wing, energy harvesting, and flapping aircrafts are proposed as new directions in the future.

  8. Recent advance in nonlinear aeroelastic analysis and control of the aircraft

    Directory of Open Access Journals (Sweden)

    Xiang Jinwu

    2014-02-01

    Full Text Available A review on the recent advance in nonlinear aeroelasticity of the aircraft is presented in this paper. The nonlinear aeroelastic problems are divided into three types based on different research objects, namely the two dimensional airfoil, the wing, and the full aircraft. Different nonlinearities encountered in aeroelastic systems are discussed firstly, where the emphases is placed on new nonlinear model to describe tested nonlinear relationship. Research techniques, especially new theoretical methods and aeroelastic flutter control methods are investigated in detail. The route to chaos and the cause of chaotic motion of two-dimensional aeroelastic system are summarized. Various structural modeling methods for the high-aspect-ratio wing with geometric nonlinearity are discussed. Accordingly, aerodynamic modeling approaches have been developed for the aeroelastic modeling of nonlinear high-aspect-ratio wings. Nonlinear aeroelasticity about high-altitude long-endurance (HALE and fight aircrafts are studied separately. Finally, conclusions and the challenges of the development in nonlinear aeroelasticity are concluded. Nonlinear aeroelastic problems of morphing wing, energy harvesting, and flapping aircrafts are proposed as new directions in the future.

  9. APPLICATION FOR AIRCRAFT TRACKING

    OpenAIRE

    Ostroumov, Ivan; Kuz’menko, Natalia

    2011-01-01

    Abstract. In the article the important problems of software development for aircraft tracking have beendiscussed. Position reports of ACARS have been used for aircraft tracking around the world.An algorithm of aircraft coordinates decoding and visualization of aircraft position on the map has beenrepresented.Keywords: ACARS, aircraft, internet, position, software, tracking.

  10. An Electronic Workshop on the Performance Seeking Control and Propulsion Controlled Aircraft Results of the F-15 Highly Integrated Digital Electronic Control Flight Research Program

    Science.gov (United States)

    Powers, Sheryll Goecke (Compiler)

    1995-01-01

    Flight research for the F-15 HIDEC (Highly Integrated Digital Electronic Control) program was completed at NASA Dryden Flight Research Center in the fall of 1993. The flight research conducted during the last two years of the HIDEC program included two principal experiments: (1) performance seeking control (PSC), an adaptive, real-time, on-board optimization of engine, inlet, and horizontal tail position on the F-15; and (2) propulsion controlled aircraft (PCA), an augmented flight control system developed for landings as well as up-and-away flight that used only engine thrust (flight controls locked) for flight control. In September 1994, the background details and results of the PSC and PCA experiments were presented in an electronic workshop, accessible through the Dryden World Wide Web (http://www.dfrc.nasa.gov/dryden.html) and as a compact disk.

  11. Monocular Vision System for Fixed Altitude Flight of Unmanned Aerial Vehicles.

    Science.gov (United States)

    Huang, Kuo-Lung; Chiu, Chung-Cheng; Chiu, Sheng-Yi; Teng, Yao-Jen; Hao, Shu-Sheng

    2015-01-01

    The fastest and most economical method of acquiring terrain images is aerial photography. The use of unmanned aerial vehicles (UAVs) has been investigated for this task. However, UAVs present a range of challenges such as flight altitude maintenance. This paper reports a method that combines skyline detection with a stereo vision algorithm to enable the flight altitude of UAVs to be maintained. A monocular camera is mounted on the downside of the aircraft's nose to collect continuous ground images, and the relative altitude is obtained via a stereo vision algorithm from the velocity of the UAV. Image detection is used to obtain terrain images, and to measure the relative altitude from the ground to the UAV. The UAV flight system can be set to fly at a fixed and relatively low altitude to obtain the same resolution of ground images. A forward-looking camera is mounted on the upside of the aircraft's nose. In combination with the skyline detection algorithm, this helps the aircraft to maintain a stable flight pattern. Experimental results show that the proposed system enables UAVs to obtain terrain images at constant resolution, and to detect the relative altitude along the flight path. PMID:26184213

  12. TC18钛合金焊接技术在飞机起落架制造中的应用研究%Application Research on TC18 Titanium Alloy Welding Technology in Manufactureof Aircraft Landing Gear

    Institute of Scientific and Technical Information of China (English)

    胡愈刚; 王晓平; 周亮

    2011-01-01

    在国内某型舰载机研制中,首次在起落架制造中开展了TC18钛合金焊接技术应用研究,通过试验研究,形成了完整实用的TC18钛合金焊接技术,能满足国产舰载机和其他新型飞机起落架的研制生产需求.%Application research of TC18 titanium alloy welding technology is first time carried out in the manufacture of aircraft landing gear during the development of domestic shipboard aircraft.Through experiments, a complete and practical titanium welding technology is formed, which can meet the needs for the development and production of domestic shipboard aircraft and other new types of aircrafts' landing gear manufacturing.

  13. Operations of Suborbital Research Platforms to Obtain Remote Sensing Data

    Science.gov (United States)

    Hines, Dennis O.

    2014-01-01

    The Armstrong Flight Research Center (AFRC) operates six highly modified aircraft in support the NASA science mission.These include two ER-2 aircraft, a DC-8, a G-III, and two Global Hawks. The NASA science missions demands that these aircraft be deployed around the globe while carrying a variety of science instruments. The ER-2 reconnaissance aircraft provides routine access to altitudes over 70,000 ft (20km) for large payloads and with an endurance of over 10hours. Recently the ER-2s have conducted convective storm research missions in the mid-western United States and supported the development of new instruments. The DC-8 is a four-engine jetliner that operates for up to 12 hours ataltitudes that range from the surface to 42,000 ft (13 km). Although its flight envelope is equivalent to conventional.

  14. Aircraft Cabin Environmental Quality Sensors

    Energy Technology Data Exchange (ETDEWEB)

    Gundel, Lara; Kirchstetter, Thomas; Spears, Michael; Sullivan, Douglas

    2010-05-06

    The Indoor Environment Department at Lawrence Berkeley National Laboratory (LBNL) teamed with seven universities to participate in a Federal Aviation Administration (FAA) Center of Excellence (COE) for research on environmental quality in aircraft. This report describes research performed at LBNL on selecting and evaluating sensors for monitoring environmental quality in aircraft cabins, as part of Project 7 of the FAA's COE for Airliner Cabin Environmental Research (ACER)1 effort. This part of Project 7 links to the ozone, pesticide, and incident projects for data collection and monitoring and is a component of a broader research effort on sensors by ACER. Results from UCB and LBNL's concurrent research on ozone (ACER Project 1) are found in Weschler et al., 2007; Bhangar et al. 2008; Coleman et al., 2008 and Strom-Tejsen et al., 2008. LBNL's research on pesticides (ACER Project 2) in airliner cabins is described in Maddalena and McKone (2008). This report focused on the sensors needed for normal contaminants and conditions in aircraft. The results are intended to complement and coordinate with results from other ACER members who concentrated primarily on (a) sensors for chemical and biological pollutants that might be released intentionally in aircraft; (b) integration of sensor systems; and (c) optimal location of sensors within aircraft. The parameters and sensors were selected primarily to satisfy routine monitoring needs for contaminants and conditions that commonly occur in aircraft. However, such sensor systems can also be incorporated into research programs on environmental quality in aircraft cabins.

  15. Autonomous Aircraft Operations using RTCA Guidelines for Airborne Conflict Management

    Science.gov (United States)

    Krishnamurthy, Karthik; Wing, David J.; Barmore, Bryan E.; Barhydt, Richard; Palmer, Michael T.; Johnson, Edward J.; Ballin, Mark G.; Eischeid, Todd M.

    2003-01-01

    A human-in-the-loop experiment was performed at the NASA Langley Research Center to study the feasibility of DAG-TM autonomous aircraft operations in highly constrained airspace. The airspace was constrained by a pair of special-use airspace (SUA) regions on either side of the pilot's planned route. Traffic flow management (TFM) constraints were imposed as a required time of arrival and crossing altitude at an en route fix. Key guidelines from the RTCA Airborne Conflict Management (ACM) concept were applied to autonomous aircraft operations for this experiment. These concepts included the RTCA ACM definitions of distinct conflict detection and collision avoidance zones, and the use of a graded system of conflict alerts for the flight crew. Three studies were conducted in the course of the experiment. The first study investigated the effect of hazard proximity upon pilot ability to meet constraints and solve conflict situations. The second study investigated pilot use of the airborne tools when faced with an unexpected loss of separation (LOS). The third study explored pilot interactions in an over-constrained conflict situation, with and without priority rules dictating who should move first. Detailed results from these studies were presented at the 5th USA/Europe Air Traffic Management R&D Seminar (ATM2003). This overview paper focuses on the integration of the RTCA ACM concept into autonomous aircraft operations in highly constrained situations, and provides an overview of the results presented at the ATM2003 seminar. These results, together with previously reported studies, continue to support the feasibility of autonomous aircraft operations.

  16. Exercise and Training at Altitudes: Physiological Effects and Protocols

    Directory of Open Access Journals (Sweden)

    Olga Cecilia Vargas Pinilla

    2014-01-01

    Full Text Available An increase in altitude leads to a proportional fall in the barometric pressure, and a decrease in atmospheric oxygen pressure, producing hypobaric hypoxia that affects, in different degrees, all body organs, systems and functions. The chronically reduced partial pressure of oxygen causes that individuals adapt and adjust to physiological stress. These adaptations are modulated by many factors, including the degree of hypoxia related to altitude, time of exposure, exercise intensity and individual conditions. It has been established that exposure to high altitude is an environmental stressor that elicits a response that contributes to many adjustments and adaptations that influence exercise capacity and endurance performance. These adaptations include in crease in hemoglobin concentration, ventilation, capillary density and tissue myoglobin concentration. However, a negative effect in strength and power is related to a decrease in muscle fiber size and body mass due to the decrease in the training intensity. Many researches aim at establishing how training or living at high altitudes affects performance in athletes. Training methods, such as living in high altitudes training low, and training high-living in low altitudes have been used to research the changes in the physical condition in athletes and how the physiological adaptations to hypoxia can enhanceperformance at sea level. This review analyzes the literature related to altitude training focused on how physiological adaptations to hypoxic environments influence performance, and which protocols are most frequently used to train in high altitudes.

  17. Flight evaluation of a computer aided low-altitude helicopter flight guidance system

    Science.gov (United States)

    Swenson, Harry N.; Jones, Raymond D.; Clark, Raymond

    1993-01-01

    The Flight Systems Development branch of the U.S. Army's Avionics Research and Development Activity (AVRADA) and NASA Ames Research Center have developed for flight testing a Computer Aided Low-Altitude Helicopter Flight (CALAHF) guidance system. The system includes a trajectory-generation algorithm which uses dynamic programming and a helmet-mounted display (HMD) presentation of a pathway-in-the-sky, a phantom aircraft, and flight-path vector/predictor guidance symbology. The trajectory-generation algorithm uses knowledge of the global mission requirements, a digital terrain map, aircraft performance capabilities, and precision navigation information to determine a trajectory between mission way points that seeks valleys to minimize threat exposure. This system was developed and evaluated through extensive use of piloted simulation and has demonstrated a 'pilot centered' concept of automated and integrated navigation and terrain mission planning flight guidance. This system has shown a significant improvement in pilot situational awareness, and mission effectiveness as well as a decrease in training and proficiency time required for a near terrain, nighttime, adverse weather system. AVRADA's NUH-60A STAR (Systems Testbed for Avionics Research) helicopter was specially modified, in house, for the flight evaluation of the CALAHF system. The near terrain trajectory generation algorithm runs on a multiprocessor flight computer. Global Positioning System (GPS) data are integrated with Inertial Navigation Unit (INU) data in the flight computer to provide a precise navigation solution. The near-terrain trajectory and the aircraft state information are passed to a Silicon Graphics computer to provide the graphical 'pilot centered' guidance, presented on a Honeywell Integrated Helmet And Display Sighting System (IHADSS). The system design, piloted simulation, and initial flight test results are presented.

  18. Cardiovascular physiology at high altitude.

    Science.gov (United States)

    Hooper, T; Mellor, A

    2011-03-01

    The role of the cardiovascular system is to deliver oxygenated blood to the tissues and remove metabolic effluent. It is clear that this complex system will have to adapt to maintain oxygen deliver in the profound hypoxia of high altitude. The literature on the adaptation of both the systemic and pulmonary circulations to high altitude is reviewed.

  19. i-got-u GPS waypoints delineating low-altitude transects over the Arctic Network of national park units and Selawik National Wildlife Refuge, Alaska, July 2013

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — GPS waypoints delineating the flight paths for low altitude transects from a i-got-u GPS unit. Transects were conducted from small aircraft over the National Park...

  20. Garmin GPS waypoints delineating low-altitude transects over the Arctic Network of national park units and Selawik National Wildlife Refuge, Alaska, July 2013

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — GPS waypoints delineating the flight paths for low altitude transects from a Garmin GPS unit. Transects were conducted from small aircraft over the National Park...

  1. Map images portraying flight paths of low-altitude transects over the Arctic Network of national park units and Selawik National Wildlife Refuge, Alaska, July 2013

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — Maps portraying the flight paths for low altitude transects conducted from small aircraft over the National Park Service’s Arctic Network (Bering Land Bridge...

  2. Study on the Pre-research Project Management of Civil Aircraft%民用飞机预研课题管理研究

    Institute of Scientific and Technical Information of China (English)

    舒秀丽

    2015-01-01

    Pre-research project innovates critical technology and provides technological reserve for new civil air-plane type. The paper discusses the overall process of the pre-research project management of civil aircraft, con-cretely analyzes the specific requirements of each process element, summarizes the instructive implementation processes, and provides references to improve the management level.%分析和阐述了民用飞机预研课题管理的总体过程,具体研究分析了各管理过程要素的具体要求,概述了具有指导性的管理实施流程,为民用飞机预研课题管理水平的提升提供参考。

  3. High-altitude physiology: lessons from Tibet

    Science.gov (United States)

    Wagner, Peter D.; Simonson, Tatum S.; Wei, Guan; Wagner, Harrieth; Wuren, Tanna; Yan, Ma; Qin, Ga; Ge, Rili

    2013-05-01

    Polycythemia is a universal lowlander response to altitude; healthy Andean high-altitude natives also have elevated [Hb]. While this may enhance O2 transport to tissues, studies have shown that acute isovolumic changes in [Hb] do not affect exercise capacity. Many high-altitude Tibetans have evolved sea-level values of [Hb], providing a natural opportunity to study this issue. In 21 young healthy male Tibetans with [Hb] between 15 and 23 g/dl, we measured VO2MAX and O2 transport capacity at 4200m. VO2MAX was higher when [Hb] was lower (Pcardiac output and muscle O2 diffusional conductance, but neither ventilation nor the alveolar-arterial PO2 difference (AaPO2) varied with [Hb]. In contrast, Andean high altitude natives remain polycythemic with larger lungs and higher lung diffusing capacity, a smaller exercising AaPO2, and lower ventilation. The challenges now are (1) to understand the different adaptive pathways used by Andeans and Tibetans, and (2) to determine in Tibetans whether, during evolution, reduced [Hb] appeared first, causing compensatory cardiac and muscle adaptations, or if enhanced cardiac function and muscle O2 transport capacity appeared first, permitting secondary reduction in [Hb]. For (2), further research is necessary to determine the basis of enhanced cardiac function and muscle O2 transport, and identify molecular targets of evolution in heart and muscle. Putative mutations can then be timed and compared to appearance of those affecting [Hb].

  4. Dietary Recommendations for Cyclists during Altitude Training

    Directory of Open Access Journals (Sweden)

    Małgorzata Michalczyk

    2016-06-01

    Full Text Available The concept of altitude or hypoxic training is a common practice in cycling. However, several strategies for training regimens have been proposed, like “live high, train high” (LH-TH, “live high, train low” (LH-TL or “intermittent hypoxic training” (IHT. Each of them combines the effect of acclimatization and different training protocols that require specific nutrition. An appropriate nutrition strategy and adequate hydration can help athletes achieve their fitness and performance goals in this unfriendly environment. In this review, the physiological stress of altitude exposure and training will be discussed, with specific nutrition recommendations for athletes training under such conditions. However, there is little research about the nutrition demands of athletes who train at moderate altitude. Our review considers energetic demands and body mass or body composition changes due to altitude training, including respiratory and urinary water loss under these conditions. Carbohydrate intake recommendations and hydration status are discussed in detail, while iron storage and metabolism is also considered. Last, but not least the risk of increased oxidative stress under hypoxic conditions and antioxidant supplementation suggestions are presented.

  5. Dietary Recommendations for Cyclists during Altitude Training.

    Science.gov (United States)

    Michalczyk, Małgorzata; Czuba, Miłosz; Zydek, Grzegorz; Zając, Adam; Langfort, Józef

    2016-01-01

    The concept of altitude or hypoxic training is a common practice in cycling. However, several strategies for training regimens have been proposed, like "live high, train high" (LH-TH), "live high, train low" (LH-TL) or "intermittent hypoxic training" (IHT). Each of them combines the effect of acclimatization and different training protocols that require specific nutrition. An appropriate nutrition strategy and adequate hydration can help athletes achieve their fitness and performance goals in this unfriendly environment. In this review, the physiological stress of altitude exposure and training will be discussed, with specific nutrition recommendations for athletes training under such conditions. However, there is little research about the nutrition demands of athletes who train at moderate altitude. Our review considers energetic demands and body mass or body composition changes due to altitude training, including respiratory and urinary water loss under these conditions. Carbohydrate intake recommendations and hydration status are discussed in detail, while iron storage and metabolism is also considered. Last, but not least the risk of increased oxidative stress under hypoxic conditions and antioxidant supplementation suggestions are presented. PMID:27322318

  6. 民用飞机客舱地板横梁结构研究%Research on Cabin Floor Crossbeam Structure for Commercial Aircraft

    Institute of Scientific and Technical Information of China (English)

    孙洁琼

    2016-01-01

    The cabin floor support structure is one of the important segments on commercial aircraft fuselage. The floor crossbeam takes the loads between passengers and seats, which has to be attached to seat track, post and fuse-lage frame. This paper introduces the typical crossbeam structure and used material, and analyzes the positive and negative properties. At last, the conclusion of the crossbeam structure concept was given. The research could pro-vide a useful reference to civil aircraft structure design.%客舱地板梁结构是民用飞机机身结构的重要组成部分,其中地板横梁承担着旅客及座椅的载荷,需要分别与地板纵梁、支柱和机身框连接,是比较关键的结构。对典型机型的地板横梁结构形式和材料进行了介绍,并分析优缺点,最后对民用飞机地板横梁结构方案进行了总结。为民用飞机客舱地板梁概念设计提供参考和借鉴。

  7. Structural integrity in aircraft.

    Science.gov (United States)

    Hardrath, H. F.

    1973-01-01

    The paper reviews briefly the current design philosophies for achieving long, efficient, and reliable service in aircraft structures. The strengths and weaknesses of these design philosophies and their demonstrated records of success are discussed. The state of the art has not been developed to the point where designing can be done without major test inspection and maintenance programs. A broad program of research is proposed through which a viable computerized design scheme will be provided during the next decade. The program will organize and correlate existing knowledge on fatigue and fracture behavior, identify gaps in this knowledge, and guide specific research to upgrade design capabilities.

  8. Unmanned Aircraft Systems Used over Western U.S. Rangelands to Characterize Terrestrial Ecosystems

    Science.gov (United States)

    Rango, A.

    2015-12-01

    New remote sensing methods to quantify terrestrial ecosystems have developed rapidly over the past 10 years. New platforms with improved aeronautical capabilities have become known as Unmanned Aircraft Systems (UAS). In addition to the new aircraft, sensors are becoming smaller and some can fit into limited payload bays. The miniaturization process is well underway, but much remains to be done. Rather than using a wide variety of sensors, a limited number of instruments is recommended. At the moment we fly 2-3 instruments (digital SLR camera, 6-band multispectral camera, and single video camera). Our flights are primarily over low population density western U.S. rangeland with objectives to assess rangeland health, active erosion, vegetation change, phenology, livestock movement, and vegetation type consumed by grazing animals. All of our UAS flights are made using a serpentine flight path with overlapping images at an altitude of 700 ft (215 m). This altitude allows hyperspatial imagery with a resolution of 5-15 cm depending upon the sensor being used, and it allows determination of vegetation type based on the plant structure and vegetation geometries, or by multispectral analysis. In addition to advances in aircraft and sensor technology, image processing software has become more sophisticated. Future development is necessary, and we can expect improvement in sensors, aircraft, data collection, and application to terrestrial ecosystems. Of 17 ARS research laboratories across the country four laboratories are interested in future UAS applications and another 13 already have at least one UAS. In 2015 the Federal Aviation Administration proposed a framework of recommendations that would allow routine use of certain small UAS (those weighing less than 55 lb (25 kg)). Although these new regulations will provide increased flexibility in how flights are made, other operations will still require the use of a Certificate of Authorization.

  9. An Analysis of Ball Lightning-Aircraft Incidents

    Science.gov (United States)

    Doe, R. K.; Keul, A. G.; Bychkov, V.

    2009-12-01

    Lightning is a rare but regular phenomenon for air traffic. Research and design have created aircraft that withstand average lightning strikes. Ball lightning (BL), a metastable, rare lightning type, is also observed from (and within) aircraft. Science and the media focused on individual BL incidents and did not analyze general patterns. Lacking established incident reporting channels, most BL observations are still passed on as “aviation lore”. To overcome this unsatisfactory condition, the authors collected and analyzed an international data bank of 87 BL-aircraft case histories from 1938 to 2007. 37 Russian military and civil BL reports were provided by the third author. Of the whole sample, 36 (41%) cases occurred over Russia/RF/SU, 24 (28%) over USA/Canada, 23 (26%) over Europe, and 4 (5%) over Asia/Pacific. Various types of military (US: C-54/141, B-52, KC-97/135 Stratotankers, C130, P-3 Orion, RF/SU: PO-2, IL, SU, TU, MIG; Nimrod, Saab-105) and civilian aircraft (US: DC-3/6, Metroliner, B-727/737/757/777, RF/SU: AN, TU; VC-10, Fokker F-28, CRJ-200), as well as general aviation (C-172, Falcon-20), were involved. BL reports show a flat annual April to August maximum. At BL impact, 15 aircraft were climbing, 7 descending; most were at cruising altitude. 42 (48%) reported BL outside the aircraft, 37 (43%) inside, 7 (8%) both in-and outside. No damage was reported in 34 (39%) cases, 39 objects (45%) caused minor damage, 11 major damage (13%), 3 even resulted in military aircraft losses. 3 objects caused minor, 1 major crew injury. 23 damage cases were associated with BL inside the fuselage; all 4 crew injury cases were of that BL type. Mean size is described as 25 cm, sometimes over 1 m, color 30% in the yellow-red, 10% in the blue-green spectral region, 8% white, duration around 10 seconds, sometimes over 1 minute. 33 (38%) incidents ended with an explosion of the object. Thunderstorm conditions were reported by 25 (29%) of the observers, 9 (10%) said there

  10. NACA Aircraft on Lakebed - D-558-2, X-1B, and X-1E

    Science.gov (United States)

    1955-01-01

    Early NACA research aircraft on the lakebed at the High Speed Research Station in 1955: Left to right: X-1E, D-558-2, X-1B There were four versions of the original Bell X-1 rocket-powered research aircraft that flew at the NACA High-Speed Flight Research Station, Edwards, California. The bullet-shaped X-1 aircraft were built by Bell Aircraft Corporation, Buffalo, N.Y. for the U.S. Army Air Forces (after 1947, U.S. Air Force) and the National Advisory Committee for Aeronautics (NACA). The X-1 Program was originally designated the XS-1 for EXperimental Supersonic. The X-1's mission was to investigate the transonic speed range (speeds from just below to just above the speed of sound) and, if possible, to break the 'sound barrier.' Three different X-1s were built and designated: X-1-1, X-1-2 (later modified to become the X-1E), and X-1-3. The basic X-1 aircraft were flown by a large number of different pilots from 1946 to 1951. The X-1 Program not only proved that humans could go beyond the speed of sound, it reinforced the understanding that technological barriers could be overcome. The X-1s pioneered many structural and aerodynamic advances including extremely thin, yet extremely strong wing sections; supersonic fuselage configurations; control system requirements; powerplant compatibility; and cockpit environments. The X-1 aircraft were the first transonic-capable aircraft to use an all-moving stabilizer. The flights of the X-1s opened up a new era in aviation. The first X-1 was air-launched unpowered from a Boeing B-29 Superfortress on January 25, 1946. Powered flights began in December 1946. On October 14, 1947, the X-1-1, piloted by Air Force Captain Charles 'Chuck' Yeager, became the first aircraft to exceed the speed of sound, reaching about 700 miles per hour (Mach 1.06) and an altitude of 43,000 feet. The number 2 X-1 was modified and redesignated the X-1E. The modifications included adding a conventional canopy, an ejection seat, a low-pressure fuel system

  11. A comparative analysis of the influence of weather on the flight altitudes of birds

    NARCIS (Netherlands)

    J. Shamoun-Baranes; E. van Loon; H. van Gasteren; J. van Belle; W. Bouten; L. Buurma

    2006-01-01

    Birds pose a serious risk to flight safety worldwide. A Bird Avoidance Model (BAM) is being developed in the Netherlands to reduce the risk of bird-aircraft collisions. In order to develop a temporally and spatially dynamic model of bird densities, data are needed on the flight-altitude distribution

  12. Measurements of HCl and HNO3 with the new research aircraft HALO - Quantification of the stratospheric contribution to the O3 and HNO3 budget in the UT/LS

    Science.gov (United States)

    Jurkat, Tina; Kaufmann, Stefan; Voigt, Christiane; Zahn, Andreas; Schlager, Hans; Engel, Andreas; Bönisch, Harald; Dörnbrack, Andreas

    2013-04-01

    Dynamic and chemical processes modify the ozone (O3) budget of the upper troposphere/lower stratosphere, leading to locally variable O3 trends. In this region, O3 acts as a strong greenhouse gas with a net positive radiative forcing. It has been suggested, that the correlation of the stratospheric tracer hydrochloric acid (HCl) with O3 can be used to quantify stratospheric O3 in the UT/LS region (Marcy et al., 2004). The question is, whether the stratospheric contribution to the nitric acid (HNO3) budget in the UT/LS can be determined by a similar approach in order to differentiate between tropospheric and stratospheric sources of HNO3. To this end, we performed in situ measurements of HCl and HNO3 with a newly developed Atmospheric chemical Ionization Mass Spectrometer (AIMS) during the TACTS (Transport and Composition in the UTLS) / ESMVal (Earth System Model Validation) mission in August/September 2012. The linear quadrupole mass spectrometer deployed aboard the new German research aircraft HALO was equipped with a new discharge source generating SF5- reagent ions and an in-flight calibration allowing for accurate, spatially highly resolved trace gas measurements. In addition, sulfur dioxide (SO2), nitrous acid (HONO) and chlorine nitrate (ClONO2) have been simultaneously detected with the AIMS instrument. Here, we show trace gas distributions of HCl and HNO3 measured during a North-South transect from Northern Europe to Antarctica (68° N to 65° S) at 8 to 15 km altitude and discuss their latitude dependence. In particular, we investigate the stratospheric ozone contribution to the ozone budget in the mid-latitude UT/LS using correlations of HCl with O3. Differences in these correlations in the subtropical and Polar regions are discussed. A similar approach is used to quantify the HNO3 budget of the UT/LS. We identify unpolluted atmospheric background distributions and various tropospheric HNO3 sources in specific regions. Our observations can be compared to

  13. Reinterpreting aircraft measurements in anisotropic scaling turbulence

    Directory of Open Access Journals (Sweden)

    S. Lovejoy

    2009-02-01

    Full Text Available Due to unavoidable vertical fluctuations, the interpretation of atmospheric aircraft measurements requires a theory of turbulence. Until now virtually all the relevant theories have been isotropic. However almost all the available data on the vertical structure shows that it is scaling but with exponents different from the horizontal: the turbulence is anisotropic not isotropic. In this paper, we show how this can lead to spurious breaks in the scaling and to the spurious appearance of the vertical scaling exponent at large horizontal lags.

    We demonstrate this using 16 legs of Gulfstream 4 tropospheric data following isobars each between 500 and 3200 km in length. First we show that the horizontal spectra of the aircraft altitude are nearly k−5/3 (although smoothed by aircraft intertia at scales <3 km. In addition, we show that the altitude and pressure fluctuations along these fractal trajectories have a high degree of coherence with the measured wind (especially with its longitudinal component. There is also a strong phase relation between the altitude, pressure and wind fluctuations with all of these effects occurring over the entire range of scales so that the trajectories influence the wind measurements over large ranges of scale. In comparison, the temperature and humidity have no apparent scale breaks and the corresponding coherencies and phases are low reinforcing the hypothesis that it is the aircraft trajectory that is causally linked to the scale breaks in the wind measurements.

    Using spectra and structure functions we then estimate the small and large scale exponents finding that they are close to the Kolmogorov values (5/3, 1/3 and the vertical values (2.4, 0.73 respectively (for the spectral and real space scaling exponents (β, H the latter are close to those estimated by drop sondes (2.4, 0.75 in the vertical direction. In addition, for each leg we estimate the energy flux, the sphero

  14. Asteroid airburst altitude vs. strength

    Science.gov (United States)

    Robertson, Darrel; Wheeler, Lorien; Mathias, Donovan

    2016-10-01

    Small NEO asteroids (plans and emergency management.Strong asteroids, such as a monolithic boulder, fail and create peak energy deposition close to the altitude at which ram dynamic pressure exceeds the material cohesive strength. Weaker asteroids, such as a rubble pile, structurally fail at higher altitude, but it requires the increased aerodynamic pressure at lower altitude to disrupt and disperse the rubble. Consequently the resulting airbursts have a peak energy deposition at similar altitudes.In this study hydrocode simulations of the entry and break-up of small asteroids were performed to examine the effect of strength, size, composition, entry angle, and speed on the resulting airburst. This presentation will show movies of the simulations, the results of peak burst height, and the comparison to semi-analytical models.

  15. Venus Altitude Cycling Balloon Project

    Data.gov (United States)

    National Aeronautics and Space Administration — The ISTAR Group ( IG) and team mate Thin Red Line Aerospace (TRLA) propose a Venus altitude cycling balloon (Venus ACB), an innovative superpressure balloon...

  16. Conceptual design of hybrid-electric transport aircraft

    Science.gov (United States)

    Pornet, C.; Isikveren, A. T.

    2015-11-01

    The European Flightpath 2050 and corresponding Strategic Research and Innovation Agenda (SRIA) as well as the NASA Environmentally Responsible Aviation N+ series have elaborated aggressive emissions and external noise reduction targets according to chronological waypoints. In order to deliver ultra-low or even zero in-flight emissions levels, there exists an increasing amount of international research and development emphasis on electrification of the propulsion and power systems of aircraft. Since the late 1990s, a series of experimental and a host of burgeouning commercial activities for fixed-wing aviation have focused on glider, ultra-light and light-sport airplane, and this is proving to serve as a cornerstone for more ambitious transport aircraft design and integration technical approaches. The introduction of hybrid-electric technology has dramatically expanded the design space and the full-potential of these technologies will be drawn through synergetic, tightly-coupled morphological and systems integration emphasizing propulsion - as exemplified by the potential afforded by distributed propulsion solutions. With the aim of expanding upon the current repository of knowledge associated with hybrid-electric propulsion systems a quad-fan arranged narrow-body transport aircraft equipped with two advanced Geared-Turbofans (GTF) and two Electrical Fans (EF) in an under-wing podded installation is presented in this technical article. The assessment and implications of an increasing Degree-of-Hybridization for Useful Power (HP,USE) on the overall sizing, performance as well as flight technique optimization of fuel-battery hybrid-electric aircraft is addressed herein. The integrated performance of the concept was analyzed in terms of potential block fuel burn reduction and change in vehicular efficiency in comparison to a suitably projected conventional aircraft employing GTF-only propulsion targeting year 2035. Results showed that by increasing HP,USE, significant

  17. 77 FR 14319 - Unmanned Aircraft System Test Sites

    Science.gov (United States)

    2012-03-09

    ... can be found in the Federal Register published on April 11, 2000 (65 FR 19477-19478), as well as at... operator or as complex as a high altitude surveillance aircraft patrolling our nation's borders. They may... aerial systems and national airspace almost identical to the language in the FAA Modernization and...

  18. The effects of aircraft on climate and pollution. Part II: 20-year impacts of exhaust from all commercial aircraft worldwide treated individually at the subgrid scale.

    Science.gov (United States)

    Jacobson, M Z; Wilkerson, J T; Naiman, A D; Lele, S K

    2013-01-01

    This study examines the 20-year impacts of emissions from all commercial aircraft flights worldwide on climate, cloudiness, and atmospheric composition. Aircraft emissions from each individual flight worldwide were modeled to evolve from the subgrid to grid scale with the global model described and evaluated in Part I of this study. Simulations with and without aircraft emissions were run for 20 years. Aircraft emissions were found to be responsible for -6% of Arctic surface global warming to date, -1.3% of total surface global warming, and -4% of global upper tropospheric warming. Arctic warming due to aircraft slightly decreased Arctic sea ice area. Longer simulations should result in more warming due to the further increase in CO2. Aircraft increased atmospheric stability below cruise altitude and decreased it above cruise altitude. The increase in stability decreased cumulus convection in favor of increased stratiform cloudiness. Aircraft increased total cloud fraction on average. Aircraft increased surface and upper tropospheric ozone by -0.4% and -2.5%, respectively and surface and upper-tropospheric peroxyacetyl nitrate (PAN) by -0.1% and -5%, respectively. Aircraft emissions increased tropospheric OH, decreasing column CO and CH4 by -1.7% and -0.9%, respectively. Aircraft emissions increased human mortality worldwide by -620 (-240 to 4770) deaths per year, with half due to ozone and the rest to particulate matter less than 2.5 micrometers in diameter (PM2.5). PMID:24601012

  19. NASA Global Hawk: A New Tool for Earth Science Research

    Science.gov (United States)

    Hall, Phill

    2009-01-01

    This slide presentation reviews the Global Hawk, a unmanned aerial vehicle (UAV) that NASA plans to use for Earth Sciences research. The Global Hawk is the world's first fully autonomous high-altitude, long-endurance aircraft, and is capable of conducting long duration missions. Plans are being made for the use of the aircraft on missions in the Arctic, Pacific and Western Atlantic Oceans. There are slides showing the Global Hawk Operations Center (GHOC), Flight Control and Air Traffic Control Communications Architecture, and Payload Integration and Accommodations on the Global Hawk. The first science campaign, planned for a study of the Pacific Ocean, is reviewed.

  20. China's Civil Regional Transport Aircraft Sales Model: Research on Xinzhou 60 Aircraft Market Sales Model%中国民用支线运输飞机销售模式——新舟60飞机市场销售模式研究

    Institute of Scientific and Technical Information of China (English)

    蔡长宏

    2011-01-01

    目前对飞机市场销售模式的研究还处在探讨阶段,大量的文献都是对一些普通产品做一些市场分析,在对飞机销售市场研究方面并没有过多的分析.因此,本文主要以新舟60飞机销售体系为列,运用市场细分、产品定位和渠道管理、宣传推广等理论,制定出新舟60飞机市场销售体系模式.%At present, the research on the market sales model of aircraft is still in discussion stage. A large number of literatures only do some market analysis on common products, the research on the aircraft sales market is less. Therefore, taking Xinzhou 60 aircraft sales system as an example, this article formulates Xinzhou 60 aircraft market sales system using market segment, product positioning and channel management, promotion.

  1. Cycle Counting Methods of the Aircraft Engine

    Science.gov (United States)

    Fedorchenko, Dmitrii G.; Novikov, Dmitrii K.

    2016-01-01

    The concept of condition-based gas turbine-powered aircraft operation is realized all over the world, which implementation requires knowledge of the end-of-life information related to components of aircraft engines in service. This research proposes an algorithm for estimating the equivalent cyclical running hours. This article provides analysis…

  2. Reinterpreting aircraft measurements in anisotropic scaling turbulence

    Directory of Open Access Journals (Sweden)

    S. J. Hovde

    2009-07-01

    Full Text Available Due to both systematic and turbulent induced vertical fluctuations, the interpretation of atmospheric aircraft measurements requires a theory of turbulence. Until now virtually all the relevant theories have been isotropic or "quasi isotropic" in the sense that their exponents are the same in all directions. However almost all the available data on the vertical structure shows that it is scaling but with exponents different from the horizontal: the turbulence is scaling but anisotropic. In this paper, we show how such turbulence can lead to spurious breaks in the scaling and to the spurious appearance of the vertical scaling exponent at large horizontal lags.

    We demonstrate this using 16 legs of Gulfstream 4 aircraft near the top of the troposphere following isobars each between 500 and 3200 km in length. First we show that over wide ranges of scale, the horizontal spectra of the aircraft altitude are nearly k-5/3. In addition, we show that the altitude and pressure fluctuations along these fractal trajectories have a high degree of coherence with the measured wind (especially with its longitudinal component. There is also a strong phase relation between the altitude, pressure and wind fluctuations; for scales less than ≈40 km (on average the wind fluctuations lead the pressure and altitude, whereas for larger scales, the pressure fluctuations leads the wind. At the same transition scale, there is a break in the wind spectrum which we argue is caused by the aircraft starting to accurately follow isobars at the larger scales. In comparison, the temperature and humidity have low coherencies and phases and there are no apparent scale breaks, reinforcing the hypothesis that it is the aircraft trajectory that is causally linked to the scale breaks in the wind measurements.

    Using spectra and structure functions for the wind, we then estimate their exponents (β, H at small (5/3, 1/3 and large scales (2

  3. Thermodynamic correction of particle concentrations measured by underwing probes on fast flying aircraft

    Science.gov (United States)

    Weigel, R.; Spichtinger, P.; Mahnke, C.; Klingebiel, M.; Afchine, A.; Petzold, A.; Krämer, M.; Costa, A.; Molleker, S.; Jurkat, T.; Minikin, A.; Borrmann, S.

    2015-12-01

    Particle concentration measurements with underwing probes on aircraft are impacted by air compression upstream of the instrument body as a function of flight velocity. In particular for fast-flying aircraft the necessity arises to account for compression of the air sample volume. Hence, a correction procedure is needed to invert measured particle number concentrations to ambient conditions that is commonly applicable for different instruments to gain comparable results. In the compression region where the detection of particles occurs (i.e. under factual measurement conditions), pressure and temperature of the air sample are increased compared to ambient (undisturbed) conditions in certain distance away from the aircraft. Conventional procedures for scaling the measured number densities to ambient conditions presume that the particle penetration speed through the instruments' detection area equals the aircraft speed (True Air Speed, TAS). However, particle imaging instruments equipped with pitot-tubes measuring the Probe Air Speed (PAS) of each underwing probe reveal PAS values systematically below those of the TAS. We conclude that the deviation between PAS and TAS is mainly caused by the compression of the probed air sample. From measurements during two missions in 2014 with the German Gulfstream G-550 (HALO - High Altitude LOng range) research aircraft we develop a procedure to correct the measured particle concentration to ambient conditions using a thermodynamic approach. With the provided equation the corresponding concentration correction factor ξ is applicable to the high frequency measurements of each underwing probe which is equipped with its own air speed sensor (e.g. a pitot-tube). ξ-values of 1 to 0.85 are calculated for air speeds (i.e. TAS) between 60 and 260 m s-1. From HALO data it is found that ξ does not significantly vary between the different deployed instruments. Thus, for the current HALO underwing probe configuration a parameterisation of

  4. Functions and Design Scheme of Tibet High Altitude Test Base

    Institute of Scientific and Technical Information of China (English)

    Yu Yongqing; Guo Jian; Yin Yu; Mao Yan; Li Guangfan; Fan Jianbin; Lu Jiayu; Su Zhiyi; Li Peng; Li Qingfeng; Liao Weiming; Zhou Jun

    2010-01-01

    @@ The functional orientation of the Tibet High Altitude Test Base, subordinated to the State Grid Corporation of China (SGCC), is to serve power transmission projects in high altitude areas, especially to provide technical support for southwestern hydropower delivery projects by UHVDC transmission and Qinghai-Tibet grid interconnection project. This paper presents the matters concerned during siting and planning, functions,design scheme, the main performances and parameters of the test facilities, as well as the tests and research tasks already carried out.

  5. 飞机结构单机寿命监控的几个关键问题的研究%Research on Several Key Problems of Individual Aircraft Fatigue Life Monitoring for Aircraft Structure

    Institute of Scientific and Technical Information of China (English)

    张泰峰; 孙文胜; 杨晓华; 赵维义

    2011-01-01

    飞机结构的使用寿命取决于使用方法,实施单机寿命监控能够有效地体现出这种差异性.基于飞行参数监控的思想,综合考虑了计算精度和计算效率,对不同采样率和不同滤波门槛值的影响进行了分析,确定了适用的采样率和门槛值;综合分析了不同情况下外挂质量对损伤计算结果的影响,为飞机结构实施单机寿命监控提供了技术保障.%The life of aircraft structure depends on its manipulating methods, and individual aircraft fatigue life monitoring is an effective way to reflect the difference. Based on the theory of flight data monitoring, the influences of different sample rate and different threshold were analyzed in detail by considering its efficiency and precision, and the sample rate and threshold for certain aircraft were proposed. The influence of different suspension weights on calculation result of damage was discussed. The purpose was to provide theoretical basis for individual aircraft fatigue life monitoring.

  6. Propulsion controlled aircraft computer

    Science.gov (United States)

    Cogan, Bruce R. (Inventor)

    2010-01-01

    A low-cost, easily retrofit Propulsion Controlled Aircraft (PCA) system for use on a wide range of commercial and military aircraft consists of an propulsion controlled aircraft computer that reads in aircraft data including aircraft state, pilot commands and other related data, calculates aircraft throttle position for a given maneuver commanded by the pilot, and then displays both current and calculated throttle position on a cockpit display to show the pilot where to move throttles to achieve the commanded maneuver, or is automatically sent digitally to command the engines directly.

  7. High-altitude pulmonary hypertension

    Directory of Open Access Journals (Sweden)

    X-Q. Xu

    2009-03-01

    Full Text Available High-altitude pulmonary hypertension (HAPH is a specific disease affecting populations that live at high elevations. The prevalence of HAPH among those residing at high altitudes needs to be further defined. Whereas reduction in nitric oxide production may be one mechanism for the development of HAPH, the roles of endothelin-1 and prostaglandin I2 pathways in the pathogenesis of HAPH deserve further study. Although some studies have suggested that genetic factors contribute to the pathogenesis of HAPH, data published to date are insufficient for the identification of a significant number of gene polymorphims in HAPH. The clinical presentation of HAPH is nonspecific. Exertional dyspnoea is the most common symptom and signs related to right heart failure are common in late stages of HAPH. Echocardiography is the most useful screening tool and right heart catheterisation is the gold standard for the diagnosis of HAPH. The ideal management for HAPH is migration to lower altitudes. Phosphodiesterase 5 is an attractive drug target for the treatment of HAPH. In addition, acetazolamide is a promising therapeutic agent for high-altitude pulmonary hypertension. To date, no evidence has confirmed whether endothelin-receptor antagonists have efficacy in the treatment of high-altitude pulmonary hypertension.

  8. Dynamic Flight Simulation of aircraft and its comparison to Flight tests

    Directory of Open Access Journals (Sweden)

    Reza Khaki

    2015-09-01

    Full Text Available Nowadays obtaining data for air vehicles researches and analyses is very expensive and risky through the flight tests. Therefore using flight simulation is usually used for the mentioned researches by aerospace science researchers. In this paper, dynamic flight simulation has been performed by airplane nonlinear equations modelling. In these equations, aerodynamic coefficients and stability derivatives have an important role. Therefore, the stability derivatives for typical aircraft are calculated on various flight conditions by analytical and numerical methods. Flight conditions include of Mach number, altitude, angle of attack, control surfaces and CG position variations. The obtained derivatives are used in the form of look up table for dynamic flight simulation and virtual flight. In order to validate the simulation results, the under investigation maneuvres parameters are recorded during many real flights. The obtained data from flight tests are compared with the outputs of flight simulations. The results indicate that less than 13% differences are found in different parts of the maneuvres.

  9. Long-range pollution transport during the MILAGRO-2006 campaign: a case study of a major Mexico City outflow event using free-floating altitude-controlled balloons

    Directory of Open Access Journals (Sweden)

    P. B. Voss

    2010-02-01

    Full Text Available One of the major objectives of the Megacities Initiative: Local And Global Research Observations (MILAGRO-2006 campaign was to investigate the long-range transport of polluted Mexico City Metropolitan Area (MCMA outflow and determine its downwind impacts on air quality and climate. Six research aircraft, including the National Center for Atmospheric Research (NCAR C-130, made extensive chemical, aerosol, and radiation measurements above MCMA and more than 1000 km downwind in order to characterize the evolution of the outflow as it aged and dispersed over the Mesa Alta and Gulf of Mexico. As part of this effort, free-floating Controlled-Meteorological (CMET balloons, commanded to change altitude via satellite, made repeated profile measurements of winds and state variables within the advecting outflow. In this paper, we present an analysis based on the data from two CMET balloons that were launched near Mexico City on the afternoon of 18 March 2006 and floated downwind with the MCMA pollution for nearly 30 h. The repeating profile measurements show the evolving structure of the outflow in considerable detail: its stability and stratification, interaction with other air masses, mixing episodes, and dispersion into the regional background. Air parcel trajectories, computed directly from the balloon wind profiles, show three different transport pathways on 18–19 March: (a high-altitude advection of the top of the MCMA mixed layer, (b mid-level outflow over the Sierra Madre Oriental followed by decoupling and isolated transport over the Gulf, and (c low-altitude outflow with entrainment into a cleaner westerly jet below the plateau. The C-130 aircraft intercepted the balloon-based trajectories three times on 19 March, once along each of these pathways. In all three cases, distinct peaks in the urban tracer signatures and LIDAR backscatter imagery were consistent with MCMA pollution. The coherence of the high-altitude outflow was well preserved

  10. Certification and safety aspects relating to the transport of passengers on high altitude balloons in Europe

    Science.gov (United States)

    Schoenmaker, Annelie

    2014-07-01

    High-altitude balloons typically fly between 25 and 50 km in altitude, which, while below the Karman line of 100 km, is yet far above the altitudes typically flown by aircraft. For example, the highest-flying commercial aircraft - the Concorde - had a maximum cruising altitude of only 18 km. zero2infinity, a Spanish company, is currently developing a pressurized pod named “bloon” which will be capable of lifting six people, including two pilot crew members and four paying passengers, to an altitude of 36 km through the use of high-altitude balloons. The boundary between Airspace and Outer Space has never been legally defined, mostly because of the lack of activities taking place between the altitude where airplanes fly and the lowest orbiting spacecraft. High-altitude balloons do fly at these in-between altitudes and the prospect of commercializing access to these parts of the stratosphere poses some questions in a new light. Given the relatively low altitude at which they fly, it may well be that these types of balloons would be considered to operate exclusively within air space. However, given the technology involved in crewed high altitude balloon flights, which is more similar to spacecraft engineering than to traditional hot-air or gas ballooning, it is necessary to evaluate the various legal regimes, codes, and regulations that would apply to such flights, especially regarding licenses and liabilities. For high altitude balloon flights commencing in Europe, the European Aviation Safety Agency (EASA) would very likely be the competent certification or licensing agency for these flights, although there would likely be input from various national aviation authorities as well. However, because the European Commission (EC) has not yet issued regulations regarding commercial spaceflight, particularly the use of high altitude balloons, new rules and regulations governing such flights may still need to be drafted and promulgated. With the development of

  11. Aircraft engine exhaust emissions and other airport-related contributions to ambient air pollution: A review

    Science.gov (United States)

    Masiol, Mauro; Harrison, Roy M.

    2014-10-01

    Civil aviation is fast-growing (about +5% every year), mainly driven by the developing economies and globalisation. Its impact on the environment is heavily debated, particularly in relation to climate forcing attributed to emissions at cruising altitudes and the noise and the deterioration of air quality at ground-level due to airport operations. This latter environmental issue is of particular interest to the scientific community and policymakers, especially in relation to the breach of limit and target values for many air pollutants, mainly nitrogen oxides and particulate matter, near the busiest airports and the resulting consequences for public health. Despite the increased attention given to aircraft emissions at ground-level and air pollution in the vicinity of airports, many research gaps remain. Sources relevant to air quality include not only engine exhaust and non-exhaust emissions from aircraft, but also emissions from the units providing power to the aircraft on the ground, the traffic due to the airport ground service, maintenance work, heating facilities, fugitive vapours from refuelling operations, kitchens and restaurants for passengers and operators, intermodal transportation systems, and road traffic for transporting people and goods in and out to the airport. Many of these sources have received inadequate attention, despite their high potential for impact on air quality. This review aims to summarise the state-of-the-art research on aircraft and airport emissions and attempts to synthesise the results of studies that have addressed this issue. It also aims to describe the key characteristics of pollution, the impacts upon global and local air quality and to address the future potential of research by highlighting research needs.

  12. Monitoring and forecasting of great radiation hazards for spacecraft and aircrafts by online cosmic ray data

    Directory of Open Access Journals (Sweden)

    L. I. Dorman

    2005-11-01

    Full Text Available We show that an exact forecast of great radiation hazard in space, in the magnetosphere, in the atmosphere and on the ground can be made by using high-energy particles (few GeV/nucleon and higher whose transportation from the Sun is characterized by a much bigger diffusion coefficient than for small and middle energy particles. Therefore, high energy particles come from the Sun much earlier (8-20 min after acceleration and escaping into solar wind than the main part of smaller energy particles (more than 30-60 min later, causing radiation hazard for electronics and personal health, as well as spacecraft and aircrafts. We describe here principles of an automatic set of programs that begin with "FEP-Search", used to determine the beginning of a large FEP event. After a positive signal from "FEP-Search", the following programs start working: "FEP-Research/Spectrum", and then "FEP-Research/Time of Ejection", "FEP-Research /Source" and "FEP-Research/Diffusion", which online determine properties of FEP generation and propagation. On the basis of the obtained information, the next set of programs immediately start to work: "FEP-Forecasting/Spacecrafts", "FEP-Forecasting/Aircrafts", "FEP-Forecasting/Ground", which determine the expected differential and integral fluxes and total fluency for spacecraft on different orbits, aircrafts on different airlines, and on the ground, depending on altitude and cutoff rigidity. If the level of radiation hazard is expected to be dangerous for high level technology or/and personal health, the following programs will be used "FEP-Alert/Spacecrafts", "FEP-Alert/ Aircrafts", "FEP-Alert/Ground".

  13. Hormonal Changes Under Altitude Stress

    Directory of Open Access Journals (Sweden)

    H.D Brahmachari

    1977-04-01

    Full Text Available The separate effects of exposure for six hours to cold (8 degree Celsius, hypoxia (4267 m. and simulated altitude (8 degree Celsius at 4267 m.have been studied on ten human subjects in a decompression chamber, with respect to the changes in blood cortisol, ADH and urinary catecholamines. Changes in blood cortisol, PBI, ADH urinary excretion of 17-keto steroids and urine volume have been recorded on another ten subjects on acute exposure to high altitude (3505 m.. Changes in the same parameters alongwith urinary testosterone level, have been recorded on another 20 subjects on prolonged exposure for two years to high altitude (3505 m.. The results have been discussed.

  14. Spatial sensitivities of human health risk to intercontinental and high-altitude pollution

    Science.gov (United States)

    Koo, Jamin; Wang, Qiqi; Henze, Daven K.; Waitz, Ian A.; Barrett, Steven R. H.

    2013-06-01

    We perform the first long-term (>1 year) continuous adjoint simulations with a global atmospheric chemistry-transport model focusing on population exposure to fine particulate matter (PM2.5) and associated risk of early death. Sensitivities relevant to intercontinental and high-altitude PM pollution are calculated with particular application to aircraft emissions. Specifically, the sensitivities of premature mortality risk in different regions to NOx, SOx, CO, VOC and primary PM2.5 emissions as a function of location are computed. We apply the resultant sensitivity matrices to aircraft emissions, finding that NOx emissions are responsible for 93% of population exposure to aircraft-attributable PM2.5. Aircraft NOx accounts for all of aircraft-attributable nitrate exposure (as expected) and 53% of aircraft-attributable sulfate exposure due to the strong "oxidative coupling" between aircraft NOx emissions and non-aviation SO2 emissions in terms of sulfate formation. Of the health risk-weighted human PM2.5 exposure attributable to aviation, 73% occurs in Asia, followed by 18% in Europe. 95% of the air quality impacts of aircraft emissions in the US are incurred outside the US. We also assess the impact of uncertainty or changes in (non-aviation) ammonia emissions on aviation-attributable PM2.5 exposure by calculating second-order sensitivities. We note the potential application of the sensitivity matrices as a rapid policy analysis tool in aviation environmental policy contexts.

  15. Research on New-type Fire Extinguishing Agents Performance for Civil Aircraft%现代民机新型灭火剂性能研究

    Institute of Scientific and Technical Information of China (English)

    寇鸿飞

    2014-01-01

    The research background and varieties of new-type fire extinguishing agent were introduced. Physical and chemical performance, toxicity, causticity, fire extinguishing performance and environmental protection per-formance of the potential new-type fire extinguishing agent were deeply analyzed and studied. The varieties of fire extinguishing agents which are suited to be used in civil aircraft were confirmed and the advantages and disadvanta-ges of fire extinguishing agent were obtained through researching new-type fire extinguishing agent performance.%对新型灭火剂研究背景和种类进行了简要介绍,对具有开发潜力的新型灭火剂的理化性能、毒性、腐蚀性、灭火性能、环保性能进行深入分析与研究。通过对新型灭火剂性能的研究,得出每种灭火剂的优缺点,筛选出适用于现代民机灭火系统的灭火剂。

  16. Aircraft landing using GPS

    Science.gov (United States)

    Lawrence, David Gary

    The advent of the Global Positioning System (GPS) is revolutionizing the field of navigation. Commercial aviation has been particularly influenced by this worldwide navigation system. From ground vehicle guidance to aircraft landing applications, GPS has the potential to impact many areas of aviation. GPS is already being used for non-precision approach guidance; current research focuses on its application to more critical regimes of flight. To this end, the following contributions were made: (1) Development of algorithms and a flexible software architecture capable of providing real-time position solutions accurate to the centimeter level with high integrity. This architecture was used to demonstrate 110 automatic landings of a Boeing 737. (2) Assessment of the navigation performance provided by two GPS-based landing systems developed at Stanford, the Integrity Beacon Landing System, and the Wide Area Augmentation System. (3) Preliminary evaluation of proposed enhancements to traditional techniques for GPS positioning, specifically, dual antenna positioning and pseudolite augmentation. (4) Introduction of a new concept for positioning using airport pseudolites. The results of this research are promising, showing that GPS-based systems can potentially meet even the stringent requirements of a Category III (zero visibility) landing system. Although technical and logistical hurdles still exist, it is likely that GPS will soon provide aircraft guidance in all phases of flight, including automatic landing, roll-out, and taxi.

  17. Autonomous flight at low altitude with vision-based collision avoidance and GPS-based path following

    OpenAIRE

    Zufferey, Jean-Christophe; Beyeler, Antoine; Floreano, Dario

    2010-01-01

    The ability to fly at low altitude while actively avoiding collisions with the terrain and other objects is a great challenge for small unmanned aircraft. This paper builds on top of a control strategy called optiPilot whereby a series of optic-flow detectors pointed at divergent viewing directions around the aircraft main axis are linearly combined into roll and pitch commands using two sets of weights. This control strategy already proved successful at controlling flight and avoidin...

  18. Development and application of procedures to evaluate air quality and visibility impacts of low-altitude flying operations

    Energy Technology Data Exchange (ETDEWEB)

    Liebsch, E.J.

    1990-08-01

    This report describes the development and application of procedures to evaluate the effects of low-altitude aircraft flights on air quality and visibility. The work summarized in this report was undertaken as part of the larger task of assessing the various potential environmental impacts associated with low-altitude military airspaces. Accomplishing the air quality/visibility analysis for the GEIS included (1) development and application of an integrated air quality model and aircraft emissions database specifically for Military Training Route (MTR) or similar flight operations, (2) selection and application of an existing air quality model to analyze the more widespread and less concentrated aircraft emissions from military Operations Areas (MOAs) and Restricted Areas (RAs), and (3) development and application of procedures to assess impacts of aircraft emissions on visibility. Existing air quality models were considered to be inadequate for predicting ground-level concentrations of pollutants emitted by aircraft along MTRs; therefore, the Single-Aircraft Instantaneous Line Source (SAILS) and Multiple-Aircraft Instantaneous Line Source (MAILS) models were developed to estimate potential impacts along MTRs. Furthermore, a protocol was developed and then applied in the field to determine the degree of visibility impairment caused by aircraft engine exhaust plumes. 19 refs., 2 figs., 3 tabs.

  19. Research on Flight Test Planning and Management for Civil Aircraft%民用飞机试飞规划与管理技术研究

    Institute of Scientific and Technical Information of China (English)

    袁冲; 修忠信; 田海玲; Ding Zhongtao

    2014-01-01

    梳理了通用的民机试飞需求类型,讨论了民机试飞任务分工和试飞计划制订原则,分析了民机试飞科目特点和逻辑关系,研究并提出了一种民机试飞任务优化方法,系统地阐述了试飞规划与管理体系,实现了民机试飞的闭环控制,解决了国内试飞规划中未能系统研究的问题,并创建了一套具有国际先进水平的民机试飞规划与管理系统( Flight Test Control System,简称“FTCS冶)。 FTCS已在实际型号试飞工作中得到了验证和应用,起到了减少试飞架次和提高试飞效率的作用,具有实际的工程应用意义。%The article introduces the requirement types of general flight test for civil aircraft. The principles about flight test division and planning is discussed. The characteristics and logical relationship of flight test subjects are analyzed. A optimization method about flight test is researched and presented. The flight test planning and manage-ment system is systematically elaborated. A closed-loop control flight test is achieved. The problem of flight plan-ning is solved , which has not been researched in China. A set of civil aircraft flight test planning and management system ( FTPM) which has the international advanced level is created. The FTPM has been validated and applied in practical flight test, which plays a role of reducing flight test sortie and improving the efficiency. The results show it has a practical significance in engineering application.

  20. An evaluation of the performance of chemistry transport models by comparison with research aircraft observations. Part 1: Concepts and overall model performance

    Directory of Open Access Journals (Sweden)

    D. Brunner

    2003-01-01

    Full Text Available A rigorous evaluation of five global Chemistry-Transport and two Chemistry-Climate Models operated by several different groups in Europe, was performed. Comparisons were made of the models with trace gas observations from a number of research aircraft measurement campaigns during the four-year period 1995-1998. Whenever possible the models were run over the same four-year period and at each simulation time step the instantaneous tracer fields were interpolated to all coinciding observation points. This approach allows for a very close comparison with observations and fully accounts for the specific meteorological conditions during the measurement flights. This is important considering the often limited availability and representativity of such trace gas measurements. A new extensive database including all major research and commercial aircraft measurements between 1995 and 1998, as well as ozone soundings, was established specifically to support this type of direct comparison. Quantitative methods were applied to judge model performance including the calculation of average concentration biases and the visualization of correlations and RMS errors in the form of so-called Taylor diagrams. We present the general concepts applied, the structure and content of the database, and an overall analysis of model skills over four distinct regions. These regions were selected to represent various atmospheric conditions and to cover large geographical domains such that sufficient observations are available for comparison. The comparison of model results with the observations revealed specific problems for each individual model. This study suggests the further improvements needed and serves as a benchmark for re-evaluations of such improvements. In general all models show deficiencies with respect to both mean concentrations and vertical gradients of important trace gases. These include ozone, CO and NOx at the tropopause. Too strong two-way mixing across the

  1. An evaluation of the performance of chemistry transport models by comparison with research aircraft observations. Part 1: Concepts and overall model performance

    Directory of Open Access Journals (Sweden)

    D. Brunner

    2003-05-01

    Full Text Available A rigorous evaluation of five global Chemistry-Transport and two Chemistry-Climate Models operated by several different groups in Europe was performed by comparing the models with trace gas observations from a number of research aircraft measurement campaigns. Whenever possible the models were run over the four-year period 1995–1998 and at each simulation time step the instantaneous tracer fields were interpolated to all coinciding observation points. This approach allows for a very close comparison with observations and fully accounts for the specific meteorological conditions during the measurement flights, which is important considering the often limited availability and representativity of such trace gas measurements. A new extensive database including all major research aircraft and commercial airliner measurements between 1995 and 1998 as well as ozone soundings was established specifically to support this type of direct comparison. Quantitative methods were applied to judge model performance including the calculation of average concentration biases and the visualization of correlations and RMS errors in the form of so-called Taylor diagrams. We present the general concepts applied, the structure and content of the database, and an overall analysis of model skills over four distinct regions. These regions were selected to represent various degrees and types of pollution and to cover large geographical domains with sufficient availability of observations. Comparison of model results with the observations revealed specific problems for each individual model. This study suggests what further improvements are needed and can serve as a benchmark for re-evaluations of such improvements. In general all models show deficiencies with respect to both mean concentrations and vertical gradients of the important trace gases ozone, CO and NOx at the tropopause. Too strong two-way mixing across the tropopause is suggested to be the main

  2. NASA/DOD Aerospace Knowledge Diffusion Research Project. Paper 62: The Influence of Knowledge Diffusion on Aeronautics Innovation: The Research, Development, and Production of Large Commercial Aircraft in France, Germany, and the United Kingdom

    Science.gov (United States)

    Golich, Vicki L.; Pinelli, Thomas E.

    1997-01-01

    This paper focuses on how European public policies-individually and collectively - influence the diffusion of knowledge and technology. It begins with an overview of the roles played historically and currently by European governments in the Research, Development and Production (RD&P) of Large Commercial Aircraft (LCA). The analytical framework brings together literature from global political economy, comparative politics, business management, and science and technology policy studies. It distinguishes between the production of knowledge, on the one hand, and the dissemination of knowledge, on the other. France, Germany, and the United Kingdom serve as the analytical cases. The paper concludes with a call for additional research in this area, some tentative lessons learned, and a discussion of the consequences of national strategies and policies for the diffusion of knowledge and technology in an era of globalizaton.

  3. Turboprop aircraft against terrorism: a SWOT analysis of turboprop aircraft in CAS operations

    Science.gov (United States)

    Yavuz, Murat; Akkas, Ali; Aslan, Yavuz

    2012-06-01

    Today, the threat perception is changing. Not only for countries but also for defence organisations like NATO, new threat perception is pointing terrorism. Many countries' air forces become responsible of fighting against terorism or Counter-Insurgency (COIN) Operations. Different from conventional warfare, alternative weapon or weapon systems are required for such operatioins. In counter-terrorism operations modern fighter jets are used as well as helicopters, subsonic jets, Unmanned Aircraft Systems (UAS), turboprop aircraft, baloons and similar platforms. Succes and efficiency of the use of these platforms can be determined by evaluating the conditions, the threats and the area together. Obviously, each platform has advantages and disadvantages for different cases. In this research, examples of turboprop aircraft usage against terrorism and with a more general approach, turboprop aircraft for Close Air Support (CAS) missions from all around the world are reviewed. In this effort, a closer look is taken at the countries using turboprop aircraft in CAS missions while observing the fields these aircraft are used in, type of operations, specifications of the aircraft, cost and the maintenance factors. Thus, an idea about the convenience of using these aircraft in such operations can be obtained. A SWOT analysis of turboprop aircraft in CAS operations is performed. This study shows that turboprop aircraft are suitable to be used in counter-terrorism and COIN operations in low threat environment and is cost benefical compared to jets.

  4. Optimal Sizing of a Photovoltaic-Hydrogen Power System for HALE Aircraft by means of Particle Swarm Optimization

    Directory of Open Access Journals (Sweden)

    Victor M. Sanchez

    2015-01-01

    Full Text Available Over the last decade there has been a growing interest in the research of feasibility to use high altitude long endurance (HALE aircrafts in order to provide mobile communications. The use of HALEs for telecommunication networks has the potential to deliver a wide range of communication services (from high-quality voice to high-definition videos, as well as high-data-rate wireless channels cost effectively. One of the main challenges of this technology is to design its power supply system, which must provide the enough energy for long time flights in a reliable way. In this paper a photovoltaic/hydrogen system is proposed as power system for a HALE aircraft due its high power density characteristic. In order to obtain the optimal sizing for photovoltaic/hydrogen system a particle swarm optimizer (PSO is used. As a case study, theoretical design of the photovoltaic/hydrogen power system for three different HALE aircrafts located at 18° latitude is presented. At this latitude, the range of solar radiation intensity was from 310 to 450 Wh/sq·m/day. The results obtained show that the photovoltaic/hydrogen systems calculated by PSO can operate during one year with efficacies ranging between 45.82% and 47.81%. The obtained sizing result ensures that the photovoltaic/hydrogen system supplies adequate energy for HALE aircrafts.

  5. 甚低频拖曳天线的稳态动力学研究%Research on the Steady Dynamic of VLF Trailing Antenna on an Aircraft

    Institute of Scientific and Technical Information of China (English)

    郑小洪; 侯志强; 韩维; 李冀鑫

    2012-01-01

    甚低频(Very low frequency,VLF)拖曳天线力学特征和控制是飞机对潜通信系统进一步深入论证需要解决的关键问题之一,而对其稳态动力学研究是进行甚低频拖曳天线力学特征和控制研究的基础.通过对载机盘旋时甚低频天线运动状态及其受力进行分析,应用牛顿定律建立机载甚低频拖曳天线稳态动力学模型.运用打靶法对其稳态动力学模型进行求解,分析载机速度、倾斜角和天线末端锥袋质量对天线末端锥袋量纲一半径和天线垂直度的影响.仿真结果表明在阻力系数较小时,在一定的倾斜角和载机飞行速度范围内其垂直度和天线末端量纲一半径存在多值情况,会导致拖曳天线系统的不稳定;在一定的阻力系数下,减小飞机速度,增加载机的倾斜角,能够提高甚低频拖曳天线的垂直度;单一增加天线末端锥袋质量来提高垂直度是不可行的.%The dynamic character and control of very low frequency(VLF) trailing antenna on a aircraft is one of most important problems which needs to research. The steady dynamic is the base of the dynamic character and control of the VLF trailing antenna. The mathematics model based Newton law of the trailing antenna is founded, and solved via a shooting technique. The influences of the angle of bank and the velocity of aircraft to the non-dismensionalization end radius and verticality are researched. The result shows that under the low drag, for certain ranges of the angle of bank and the velocity, the equilibrium solution is multi volume; under certain ranges of air drag, it is possible to descend the velocity of the aircraft and increase the bank angle to improve the verticality of the antenna. But it's impossible to increase the mass of the drogue only to improve the verticality of the antenna.

  6. Aircraft detection based on probability model of structural elements

    Science.gov (United States)

    Chen, Long; Jiang, Zhiguo

    2014-11-01

    Detecting aircrafts is important in the field of remote sensing. In past decades, researchers used various approaches to detect aircrafts based on classifiers for overall aircrafts. However, with the development of high-resolution images, the internal structures of aircrafts should also be taken into consideration now. To address this issue, a novel aircrafts detection method for satellite images based on probabilistic topic model is presented. We model aircrafts as the connected structural elements rather than features. The proposed method contains two major steps: 1) Use Cascade-Adaboost classier to identify the structural elements of aircraft firstly. 2) Connect these structural elements to aircrafts, where the relationships between elements are estimated by hierarchical topic model. The model places strict spatial constraints on structural elements which can identify differences between similar features. The experimental results demonstrate the effectiveness of the approach.

  7. Does altitude moderate the impact of lithium on suicide? A spatial analysis of Austria

    Directory of Open Access Journals (Sweden)

    Marco Helbich

    2013-05-01

    Full Text Available Suicide, the tenth leading cause of death worldwide, is a complex phenomenon. Models aiming to explain the interaction of ambient variables such as socioeconomic factors, lithium content of drinking water and altitude are poorly developed. While controlling for several risk factors, this research bridges two different, but complementary research lines by investigating statistically the relationship on suicide mortality between lithium levels in drinking water in response to altitude above sea level. Besides regression models with main effects, a multiplicative interaction model between lithium and altitude has been developed providing estimates at the district-level for Austria where spatial autocorrelation was accounted for through spatial filtering. The correlation results showed a negative association between lithium levels and altitude. The regression confirmed a negative association of lithium levels and suicide mortality. Altitude was found to be positively associated with suicide mortality. On the other hand, lithium effects on suicide mortality were found to be moderated by altitude. In lower altitude regions the effect turned out to be negatively related to suicide mortality, while lithium had a positive association in high-altitude regions. These results provide evidence for the fact that the relationship between lithium, altitude and suicide rates is more complex than hitherto assumed. Further research on the effects of ambient variables such as low levels of lithium on suicide is needed and particularly the lithium-altitude interaction is worth further investigation to understand possible underlying neurochemical processes.

  8. Aircraft type influence on contrail properties

    Directory of Open Access Journals (Sweden)

    P. Jeßberger

    2013-05-01

    Full Text Available The investigation of the impact of aircraft parameters on contrail properties helps to better understand the climate impact from aviation. Yet, in observations, it is a challenge to separate aircraft and meteorological influences on contrail formation. During the CONCERT campaign in November 2008, contrails from 3 Airbus passenger aircraft of type A319-111, A340-311 and A380-841 were probed at cruise under similar meteorological conditions with in-situ instruments on board the DLR research aircraft Falcon. Within the 2 min old contrails detected near ice saturation, we find similar effective diameters Deff (5.2–5.9 μm, but differences in particle number densities nice (162–235 cm−3 and in vertical contrail extensions (120–290 m, resulting in large differences in contrail optical depths τ (0.25–0.94. Hence larger aircraft produce optically thicker contrails. Based on the observations, we apply the EULAG-LCM model with explicit ice microphysics and in addition the Contrail and Cirrus Prediction model CoCiP to calculate the aircraft type impact on young contrails under identical meteorological conditions. The observed increase in τ for heavier aircraft is confirmed by the models, yet for generally smaller τ. An aircraft dependence of climate relevant contrail properties persists during contrail lifetime, adding importance to aircraft dependent model initialization. We finally derive an analytical relationship between contrail, aircraft and meteorological parameters. Near ice saturation, contrail width × τ scales linearly with fuel flow rate as confirmed by observations. For higher saturation ratios approximations from theory suggest a non-linear increase in the form (RHI–12/3. Summarized our combined results could help to more accurately assess the climate impact from aviation using an aircraft dependent contrail parameterization.

  9. Simulation development of a forward sensor-enhanced low-altitude guidance system

    Science.gov (United States)

    Zelenka, Richard E.; Swenson, Harry N.; Dearing, Munro G.; Hardy, Gordon H.

    1993-01-01

    The requirement to operate aircraft at low-altitude near the terrain is common in the military community and essential for helicopters. The risk and crew workload in this flight regime is severe, with navigation, guidance, and obstacle avoidance demanding high attention. A guidance system relying on digitized terrain elevation maps has been developed that employs airborne navigation, mission requirements, aircraft performance limits, and radar altimeter returns to generate a valley-seeking, low-altitude trajectory between waypoints for display to the pilot. This system has been flight demonstrated to 150 ft above ground level altitude, and is primarily limited by the ability of the pilot to perform obstacle detection and avoidance. In this study, a wide field of view forward sensor has been modeled and incorporated in the guidance system for the purpose of relieving the pilot of the obstacle avoidance duty. The results of a piloted, motion-based simulation of this enhanced low-altitude guidance system is presented. Simulated flights to 50 ft altitude in the presence of obstacles were demonstrated while maintaining situational awareness and close tracking of the guidance trajectory.

  10. Research on flight test technique of civil aircraft longitudinal dynamic stability%民用飞机纵向动稳定性试飞技术研究

    Institute of Scientific and Technical Information of China (English)

    宋庆国

    2001-01-01

    从试飞员的角度出发,讨论了《CCAR-25部》中有关纵向动稳定性的要求,提出了求解纵向短周期运动重阻尼的计算方法,论述了民机纵向动稳定性试飞的激励方法和试验程序,给出了短周期阻尼比的试飞员评定方法以及试飞过程中的驾驶技术要点和应注意事项。可供从事民机飞行试验的技术人员和试飞员参考。%Viewed from a test pilot, the requirements about longitudinal dynamic stability in《China Civil Aviation Regulations Part-25》are discussed. And the calculation means of big damp is given out. Each of the flight test program and prompting method of civil aircraft longitudinal dynamic stability is studied. The author presents a way about how to rate the damp ratio of short period action, also some key points of piloting skill and matters needing attention in the process of flight test are mentioned. It will give a reference to technicians and test pilots engaging in flight test research.

  11. Closed cycle propulsion for small unmanned aircraft

    Science.gov (United States)

    Hays, Thomas Chadwick

    This study evaluates the merit of closed cycle propulsion systems for use in unmanned systems. The complexity and added weight of closed cycle engines is offset by benefits in high altitude performance, operation in polluted air environments, multi-fuel operation, and potential for flight in low oxygen environments using generic thermal heat sources. Although most closed thermal cycles cannot match the efficiency and power density potential of internal combustion engines (ICE) and turbomachines in aircraft propulsion applications, the addition of design requirements regarding noise output, and operation at high altitude results in IC and CC engine's performance becoming much more comparable. Muffling devices increase backpressure on internal combustion engines thereby reducing power output and efficiency. Multi stage turbo supercharging for operation at high altitude can in some cases increase efficiency of ICE's, but at the result of significant additional complexity and cost that also reduces practical reliability because of the often intricate mechanisms involved. It is in these scenarios that closed cycle engines offer a comparable performance alternative that may prove to be simpler, cheaper, and more reliable than high altitude or low noise internal combustion or turbomachine propulsion systems.

  12. New opportunities for the study of Mediterranean storms: the unique capabilities of the Global Hawk aircraft

    Science.gov (United States)

    Cairo, F.; Curry, R. E.; Carli, B.

    2009-09-01

    Airborne measurements have often played a pivotal role in unravelling critical processess and improving our understanding of the genesis and development of atmospheric disturbances. The availability of innovative aerial platforms now opens new perspectives for the scientific research. One of these platforms is the high altitude long endurance unmanned aircraft Global Hawk (GH), which has unique capabilities in terms of altitude, range of operation, diurnal coverage and flexibility. The GH has an endurance of 31 hrs, a service ceiling of 20000 m and can host a payload of 680 kg. Since it can operate at altitudes close to the boundary conditions of radiative processes, can follow the diurnal variation of aerosol and clouds, can rapidly deploy new instruments with space-time coverage comparable to space-borne ones, it is a platform which is at the same time complementary and competitive with satellites. In fact it combines the short time deployment of aircraft instruments with the global coverage of satellite instruments, while its flight altitude allows better spatial resolution than a satellite and its endurance provides a sufficiently broad overview at a scale relevant for sinoptic meteorology studies. NASA has recently acquired two of such unmanned high altitude aircraft to address a variety of Earth Science objectives, and Italy has a decade long experience of stratospheric in-situ and remote sensing science missions using the Russian M-55 "Geophysica" high altitude piloted aircraft. There is a common interest in a bilateral cooperative program in climate change science using the GH. The collaboration between NASA and Italian scientific institutions may offer the opportunity of deploying the GH over the Mediterranean Basin. The Mediterranean area is of particular interest under many respects. As instance, it would be of great interest to measure, when possible, the 3-dimensional structure and evolution of the aerosol content over the Mediterranean, with

  13. Measurement and Characterization of Helicopter Noise at Different Altitudes

    Science.gov (United States)

    Watts, Michael E.; Greenwood, Eric; Stephenson, James

    2016-01-01

    This paper presents an overview of a flight test campaign performed at different test sites whose altitudes ranged from 0 to 7000 feet above mean sea level (AMSL) between September 2014 and February 2015. The purposes of this campaign were to: investigate the effects of altitude variation on noise generation, investigate the effects of gross weight variation on noise generation, establish the statistical variability in acoustic flight testing of helicopters, and characterize the effects of transient maneuvers on radiated noise for a medium-lift utility helicopter. In addition to describing the test campaign, results of the acoustic effects of altitude variation for the AS350 SD1 and EH-60L aircraft are presented. Large changes in acoustic amplitudes were observed in response to changes in ambient conditions when the helicopter was flown at constant indicated airspeed and gross weight at the three test sites. However, acoustic amplitudes were found to scale with ambient pressure when flight conditions were defined in terms of the non-dimensional parameters, such as the weight coefficient and effective hover tip Mach number.

  14. Study on Impedance Characteristics of Aircraft Cables

    Directory of Open Access Journals (Sweden)

    Weilin Li

    2016-01-01

    Full Text Available Voltage decrease and power loss in distribution lines of aircraft electric power system are harmful to the normal operation of electrical equipment and may even threaten the safety of aircraft. This study investigates how the gap distance (the distance between aircraft cables and aircraft skin and voltage frequency (variable frequency power supply will be adopted for next generation aircraft will affect the impedance of aircraft cables. To be more precise, the forming mechanism of cable resistance and inductance is illustrated in detail and their changing trends with frequency and gap distance are analyzed with the help of electromagnetic theoretical analysis. An aircraft cable simulation model is built with Maxwell 2D and the simulation results are consistent with the conclusions drawn from the theoretical analysis. The changing trends of the four core parameters of interest are analyzed: resistance, inductance, reactance, and impedance. The research results can be used as reference for the applications in Variable Speed Variable Frequency (VSVF aircraft electric power system.

  15. Aircraft Lightning Electromagnetic Environment Measurement

    Science.gov (United States)

    Ely, Jay J.; Nguyen, Truong X.; Szatkowski, George N.

    2011-01-01

    This paper outlines a NASA project plan for demonstrating a prototype lightning strike measurement system that is suitable for installation onto research aircraft that already operate in thunderstorms. This work builds upon past data from the NASA F106, FAA CV-580, and Transall C-180 flight projects, SAE ARP5412, and the European ILDAS Program. The primary focus is to capture airframe current waveforms during attachment, but may also consider pre and post-attachment current, electric field, and radiated field phenomena. New sensor technologies are being developed for this system, including a fiber-optic Faraday polarization sensor that measures lightning current waveforms from DC to over several Megahertz, and has dynamic range covering hundreds-of-volts to tens-of-thousands-of-volts. A study of the electromagnetic emission spectrum of lightning (including radio wave, microwave, optical, X-Rays and Gamma-Rays), and a compilation of aircraft transfer-function data (including composite aircraft) are included, to aid in the development of other new lightning environment sensors, their placement on-board research aircraft, and triggering of the onboard instrumentation system. The instrumentation system will leverage recent advances in high-speed, high dynamic range, deep memory data acquisition equipment, and fiber-optic interconnect.

  16. Longterm monitoring of ambient dose equivalent rates at aviation altitudes

    Energy Technology Data Exchange (ETDEWEB)

    Heber, B.; Burmeister, S.; Moeller, T.; Scharrenberg, E. [Institut fuer Experimentelle und Angewandte Physik, Christian-Albrechts-Universitaet zu Kiel, Kiel (Germany); Briese, J. [Deutsche Lufthansa AG, Frankfurt am Main (Germany); Burda, O.; Klages, T.; Langner, F.; Marquardt, J.; Wissmann, F. [Physikalisch-Technische Bundesanstalt, Bundesallee 100, 38116 Braunschweig Germany (Germany); Matthiae, D.; Reitz, G. [German Aerospace Center, Institute of Aerospace Medicine, Linder Hoehe, 51147 Koeln (Germany)

    2012-07-01

    The complex radiation field at flight altitudes results mainly from the interaction of energetic charged particles with atmospheric molecules and atoms and consists of secondary neutrons, protons, gamma rays, electrons, positrons and muons. Due to the continuous interactions of primary and secondary particles within the atmosphere, the intensity of each component depends on the height. Since the Earth's magnetic field acts as rigidity filter for the charged primary particles, the flux of the primary particles into the atmosphere and the resulting intensity of secondary particles depend on the geomagnetic latitude being highest over the geomagnetic poles. The main primary component consists of Galactic Cosmic Rays (GCRs), mainly protons and alpha particles, whose flux is modulated in the heliosphere. Beside this slowly varying galactic component, solar energetic particle events may temporarily increase the intensity of this radiation field. In the frame of the Radiation Monitoring on Board Aircraft (RAMONA) collaboration, three NAVIgation and DOSimetry (NAVIDOS) systems were installed in 2008 and 2009 on board of three Lufthansa Airbus A340 aircraft. They have been maintained since then by the consortium. Two of the NAVIDOS units rely on the DOSimetry TELescopes (DOSTELs), one is based on a LIULIN detector. This unique setup is ideally suited to investigate variations in the radiation field at different flight altitudes and geomagnetic positions and has been used to measure the radiation exposure during the recent extended solar minimum and thereafter. With increasing solar activity in 2010 the measured dose rates have been decreasing. Since these variations depend on the location of the aircraft, a detailed data analysis is required and presented.

  17. Weather Avoidance Guidelines for NASA Global Hawk High-Altitude UAS

    Science.gov (United States)

    Cecil, Daniel J.; Zipser, Edward J.; Velden, Chris; Monette, Sarah; Heymsfield, Gerry; Braun, Scott; Newman, Paul; Black, Pete; Black, Michael; Dunion, Jason

    2014-01-01

    NASA operates two Global Hawk unmanned aircraft systems for Earth Science research projects. In particular, they are used in the Hurricane and Severe Storm Sentinel (HS3) project during 2012, 2013, and 2014 to take measurements from the environment around tropical cyclones, and from directly above tropical cyclones. There is concern that strict adherence to the weather avoidance rules used in 2012 may sacrifice the ability to observe important science targets. We have proposed modifications to these weather avoidance rules that we believe will improve the ability to observe science targets without compromising aircraft safety. The previous guidelines, used in 2012, specified: Do not approach thunderstorms within 25 nm during flight at FL500 or below. When flying above FL500: Do not approach reported lightning within 25NM in areas where cloud tops are reported at FL500 or higher. Aircraft should maintain at least 10000 ft vertical separation from reported lightning if cloud tops are below FL500. No over-flight of cumulus tops higher than FL500. No flight into forecast or reported icing conditions. No flight into forecast or reported moderate or severe turbulence Based on past experience with high-altitude flights over tropical cyclones, we have recommended changing this guidance to: Do not approach thunderstorms within 25 nm during flight at FL500 or below. Aircraft should maintain at least 5000 ft vertical separation from significant convective cloud tops except: a) When cloud tops above FL500: In the event of reported significant lightning activity or indicators of significant overshooting tops, do not approach within 10-25 nm, depending on pilot discretion and advice from Mission Scientist. b) When cloud tops are below FL500, maintain 10000 ft separation from reported significant lightning or indicators of significant overshooting tops. No flight into forecasted or reported icing conditions. No flight into forecasted or reported moderate or severe turbulence The

  18. Analysis of Virtual Sensors for Predicting Aircraft Fuel Consumption

    Data.gov (United States)

    National Aeronautics and Space Administration — Previous research described the use of machine learning algorithms to predict aircraft fuel consumption. This technique, known as Virtual Sensors, models fuel...

  19. Aircraft Structural Analysis, Design Optimization, and Manufacturing Tool Integration Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Innovative research is proposed in integrating fundamental aircraft design processes with an emphasis on composite structures. Efficient, lightweight composite...

  20. Using Synthetic Kerosene in Civil Jet Aircraft

    NARCIS (Netherlands)

    Snijders, T.A.; Melkert, J.A.

    2008-01-01

    TU Delft in the Netherlands is performing research into the effects of the use of synthetic kerosene in aircraft. The research program consists of both desk research and tests. In the desk research gas turbine simulations will be combined with payload range performance calculations to show engine ef

  1. Sleep and Breathing at High Altitude.

    Science.gov (United States)

    Wickramasinghe, Himanshu; Anholm, James D.

    1999-01-01

    Sleep at high altitude is characterized by poor subjective quality, increased awakenings, frequent brief arousals, marked nocturnal hypoxemia, and periodic breathing. A change in sleep architecture with an increase in light sleep and decreasing slow-wave and REM sleep have been demonstrated. Periodic breathing with central apnea is almost universally seen amongst sojourners to high altitude, although it is far less common in long-standing high altitude dwellers. Hypobaric hypoxia in concert with periodic breathing appears to be the principal cause of sleep disruption at altitude. Increased sleep fragmentation accounts for the poor sleep quality and may account for some of the worsened daytime performance at high altitude. Hypoxic sleep disruption contributes to the symptoms of acute mountain sickness. Hypoxemia at high altitude is most severe during sleep. Acetazolamide improves sleep, AMS symptoms, and hypoxemia at high altitude. Low doses of a short acting benzodiazepine (temazepam) may also be useful in improving sleep in high altitude. PMID:11898114

  2. Altitude, Acute Mountain Sickness and Headache

    Science.gov (United States)

    ... Follow us on Instagram DONATE TODAY Altitude, Acute Mountain Sickness and Headache Abuse, Maltreatment, and PTSD and Their Relationship to Migraine Altitude, Acute Mountain Sickness and Headache Alcohol and Migraine Anxiety and ...

  3. Future aircraft networks and schedules

    Science.gov (United States)

    Shu, Yan

    2011-07-01

    computational results of these large-scale instances. To validate the models and solution algorithms developed, this thesis also compares the daily flight schedules that it designs with the schedules of the existing airlines. Furthermore, it creates instances that represent different economic and fuel-prices conditions and derives schedules under these different conditions. In addition, it discusses the implication of using new aircraft in the future flight schedules. Finally, future research in three areas---model, computational method, and simulation for validation---is proposed.

  4. Review of factors affecting aircraft wet runway performance

    Science.gov (United States)

    Yager, T. J.

    1983-01-01

    Problems associated with aircraft operations on wet runways are discussed and major factors which influence tire/runway braking and cornering traction capability are identified including runway characteristics, tire hydroplaning, brake system anomalies, and pilot inputs. Research results from investigations conducted at the Langley Aircraft Landing Loads and Traction Facility and from tests with instrumented ground vehicles and aircraft are summarized to indicate the effects of different aircraft, tire, and runway parameters. Several promising means are described for improving tire/runway water drainage capability, brake system efficiency, and pilot training to help optimize aircraft traction performance on wet runways.

  5. Cold Stress at High Altitudes

    Directory of Open Access Journals (Sweden)

    N. C. Majumdar

    1983-04-01

    Full Text Available The problem of cold at high altitudes has been analysed from a purely physical standpoint. It has been shown that Siple's Wind-Chill Index is not reliable because (i it does not make use of the well established principles governing the physical processes of heat transfer by convection and radiation, and (ii it assumes that the mean radiant temperature of the surroundings is the same as the ambient dry bulb temperature. A Cold Stress Index has been proposed which is likely to be a more reliable guide for assessing the climatic hazards of high altitude environments. The Index can be quickly estimated with the help of two nomograms devised for the purpose.

  6. X-ray fluorescence spectrometry using Synchrotron Radiation with applications in unmanned aircraft environmental sensing

    Science.gov (United States)

    Barberie, Sean Richard Gopal

    In this thesis I present an analytical optimization of the Synchrotron Radiation X-Ray Fluorescence (SR-XRF) technique for applications in unmanned aircraft aerosol studies. In environmental and atmospheric science, there is a pressing need for aerosol measurements at various altitudes in the atmosphere and spanning large regions. This need is currently either ignored, or met to a limited degree by studies that employ manned aircraft. There is, however, a great deal of opportunity to improve and expand on these studies using the emerging technology of unmanned aircraft systems. A newly developed aerosol sampler makes this opportunity a near-reality by its ability to collect aerosol samples in-situ from unmanned aircraft platforms. The challenge lies in analyzing these samples for elemental composition. In airborne aerosol studies, the ability to resolve where a sample was collected both spatially and temporally is limited by the sensitivity of the analysis technique. In aircraft-based aerosol collection, the length of the aerosol sample spot corresponds to distance. Thus the spatial resolution of an airborne study is limited by the amount of mass that must be collected for analysis. The SR-XRF optimizations outlined in this thesis decrease the amount of sample mass required for detectable elemental concentrations, allowing aerosol samples to be analyzed in smaller areas corresponding to smaller time steps. Since, in a flight path, time steps are directly correlated with distance, analysis of smaller time steps results in the ability to measure aerosols at higher spatial resolution. Four SR-XRF analysis configurations were experimentally tested: monochromatic beam, white beam, filtered white beam, and filtered white beam-filtered detector to determine which configuration gave the highest elemental sensitivity and selectivity. Of these tested methods, the straight polychromatic white beam configuration resulted in the best sensitivity for elements across a large

  7. The comparison of physical fitness in secondary male students in altitude and coastal areas

    OpenAIRE

    ZAHIBI, Esmaeil; ALAVI, Seyed Hossein

    2015-01-01

    The aim of this research is the comparison of physical fitness in secondary male students in altitude and coastal areas and difference between the physical fitness on based AAHPERD test. The samples consist of 450 subjects of 1017 subjects in altitude (Shahrekord) and coastal area (Mahmood Abad) in Iran in years of 2013 which were selected cluster- randomly sampling by Morgan Table. We investigated the effect of high altitude on the tests of physical fitness resident students near sea level (...

  8. Environmental stress and 3-day eventing: effects of altitude.

    Science.gov (United States)

    Foreman, J H; Waldsmith, J K; Lalum, R B

    1999-07-01

    Three-day event horses are subject to various external environmental stresses including changes in ambient temperature, humidity, altitude, and test severity. Considerable research on the adverse effects of increased heat and humidity preceded the 1996 Olympic Summer Games in Atlanta, Georgia USA, but no research has been done previously on the effects of altitude on 3-day eventing. Physical and venous blood gas data were collected on horses (n = 24) competing in the High Prairie Preliminary (CCN*) and Intermediate (CCN**) 3-day events and Preliminary Horse Trials in Parker, Colorado (1900 m above sea level). Despite the increased altitude, only post exercise rectal temperature and pH were higher (P 0.05). When these preliminary horse trial horses in Colorado were compared to those previously studied at preliminary horse trials at sea level in Arizona, post exercise HR and RR were higher (P < 0.05) and pH, PCO2, [tCO2], [HCO3-], BE and [iCa++] were lower (P < 0.05) at altitude. These data show that increased altitude (1900 m above sea level) was more stressful for 3-day event horses, but did not result in the severe physiological changes and inability to complete prescribed exercise tests seen in previous studies with increased heat and humidity. It is clear from these and previous data that increased heat and humidity are the more important environmental stressors in 3-day eventing. PMID:10659288

  9. Atmospheric mercury measurements onboard the CARIBIC passenger aircraft

    Science.gov (United States)

    Slemr, Franz; Weigelt, Andreas; Ebinghaus, Ralf; Kock, Hans H.; Bödewadt, Jan; Brenninkmeijer, Carl A. M.; Rauthe-Schöch, Armin; Weber, Stefan; Hermann, Markus; Becker, Julia; Zahn, Andreas; Martinsson, Bengt

    2016-05-01

    Goal of the project CARIBIC (Civil Aircraft for the Regular Investigation of the atmosphere Based on an Instrumented Container) is to carry out regular and detailed observations of atmospheric composition (particles and gases) at cruising altitudes of passenger aircraft, i.e. at 9-12 km. Mercury has been measured since May 2005 by a modified Tekran instrument (Tekran Model 2537 A analyser, Tekran Inc., Toronto, Canada) during monthly intercontinental flights between Europe and South and North America, Africa, and Asia. Here we describe the instrument modifications, the post-flight processing of the raw instrument signal, and the fractionation experiments.

  10. Aircraft cockpit ergonomic layout evaluation method research%飞机座舱人机布局评价方法研究

    Institute of Scientific and Technical Information of China (English)

    陈俊璇; 余隋怀; 刘国昌; 邓丽; 王文军

    2014-01-01

    针对当前座舱工效学重要性日益提升,信息量不断增加,机构愈加繁杂等特点,传统的以单个或多个部件为对象进行的人-机布局评价方法,往往造成综合评价的片面性,导致研发周期长,效率低等问题。考虑到工效学评价模糊性,提炼并建构了基于当前座舱特点的人机布局评价体系,提出基于不确定语言加权平均(U LWA)算子的多属性决策组合的研究方法,建立飞机座舱人机布局评价模型,并进行了推理和验证。%With the importance of ergonomic cockpit layout increasing, the information interaction becomes more frequently, and institutions more multifarious in the current cockpits, traditional evaluation method often results in one-sidedness comprehensive evaluation, which is mainly based on a single or a plurality of object, causing longer development cycle and lower efficiency. Considering the ambiguity of ergonomics evaluation, this paper refines and constructs an ergonomic layout evaluation system based on the characteristics of current cockpits, proposes a research method of multiple attribute decision-making combination based on Uncertain Linguistic Weighted Average(ULWA)operator, and establishes an aircraft cockpit layout evaluation model, finally been reasoning and verification.

  11. Designing A Conventional Aircraft

    OpenAIRE

    Sonei, Arash

    2014-01-01

    This paper is explaining the important design phases of dimensioning an unmanned conventional aircraft from scratch and will also design one according to a few chosen requirements. The design phases discussed will be all from wing dimensioning to stability and spin recovery, aircraft performance requirements and how to select a motor which overcomes these. As well as the optimal rate of climb for improved efficiency is discussed. In the end an aircraft which manages the set requirements and i...

  12. Lightning effects on aircraft

    Science.gov (United States)

    1977-01-01

    Direct and indirect effects of lightning on aircraft were examined in relation to aircraft design. Specific trends in design leading to more frequent lightning strikes were individually investigated. These trends included the increasing use of miniaturized, solid state components in aircraft electronics and electric power systems. A second trend studied was the increasing use of reinforced plastics and other nonconducting materials in place of aluminum skins, a practice that reduces the electromagnetic shielding furnished by a conductive skin.

  13. Aircraft Noise: Annoyance, House Prices and Valuation

    OpenAIRE

    Brooker, Peter

    2006-01-01

    “Nobody wants to buy your house. It’s the aircraft noise. You’ll have to reduce the price a lot.” Aircraft noise around airports causes annoyance, and tends to reduce the price of affected properties. Can annoyance be ‘costed’ by examining house price reductions? Are there other ways of valuing annoyance in monetary terms? This short paper summarises key research results and poses some questions.

  14. Aircraft Wake Vortex Evolution and Prediction

    OpenAIRE

    Holzäpfel, Frank

    2005-01-01

    Aircraft trailing vortices constitute both a kaleidoscope of instructive fluid dynamics phenomena and a challenge for the sustained development of safety and capacity of the air-transportation industry. The current manuscript gives an overview on the wake vortex issue which commences at its historical roots and concludes with the current status of knowledge regarding the nature and characteristics, and the modeling of aircraft wakes. The incentive of today's wake vortex research still re...

  15. Monocular Vision System for Fixed Altitude Flight of Unmanned Aerial Vehicles

    Directory of Open Access Journals (Sweden)

    Kuo-Lung Huang

    2015-07-01

    Full Text Available The fastest and most economical method of acquiring terrain images is aerial photography. The use of unmanned aerial vehicles (UAVs has been investigated for this task. However, UAVs present a range of challenges such as flight altitude maintenance. This paper reports a method that combines skyline detection with a stereo vision algorithm to enable the flight altitude of UAVs to be maintained. A monocular camera is mounted on the downside of the aircraft’s nose to collect continuous ground images, and the relative altitude is obtained via a stereo vision algorithm from the velocity of the UAV. Image detection is used to obtain terrain images, and to measure the relative altitude from the ground to the UAV. The UAV flight system can be set to fly at a fixed and relatively low altitude to obtain the same resolution of ground images. A forward-looking camera is mounted on the upside of the aircraft’s nose. In combination with the skyline detection algorithm, this helps the aircraft to maintain a stable flight pattern. Experimental results show that the proposed system enables UAVs to obtain terrain images at constant resolution, and to detect the relative altitude along the flight path.

  16. Impact of Cabin Ozone Concentrations on Passenger Reported Symptoms in Commercial Aircraft

    DEFF Research Database (Denmark)

    Bekö, Gabriel; Allen, Joseph G.; Weschler, Charles J.;

    2015-01-01

    Due to elevated ozone concentrations at high altitudes, the adverse effect of ozone on air quality, human perception and health may be more pronounced in aircraft cabins. The association between ozone and passenger-reported symptoms has not been investigated under real conditions since smoking...... was banned on aircraft and ozone converters became more common. Indoor environmental parameters were measured at cruising altitude on 83 US domestic and international flights. Passengers completed a questionnaire about symptoms and satisfaction with the indoor air quality. Average ozone concentrations were...

  17. Measurement of the energy spectrum of cosmic-ray induced neutrons aboard an ER-2 high-altitude airplane

    CERN Document Server

    Goldhagen, P E; Kniss, T; Reginatto, M; Singleterry, R C; Van Steveninck, W; Wilson, J W

    2002-01-01

    Crews working on present-day jet aircraft are a large occupationally exposed group with a relatively high average effective dose from galactic cosmic radiation. Crews of future high-speed commercial aircraft flying at higher altitudes would be even more exposed. To help reduce the significant uncertainties in calculations of such exposures, the atmospheric ionizing radiation (AIR) project, an international collaboration of 15 laboratories, made simultaneous radiation measurements with 14 instruments on five flights of a NASA ER-2 high-altitude aircraft. The primary AIR instrument was a highly sensitive extended-energy multisphere neutron spectrometer with lead and steel shells placed within the moderators of two of its 14 detectors to enhance response at high energies. Detector responses were calculated for neutrons and charged hadrons at energies up to 100 GeV using MCNPX. Neutron spectra were unfolded from the measured count rates using the new MAXED code. We have measured the cosmic-ray neutron spectrum (t...

  18. Probing Aircraft Flight Test Hazard Mitigation for the Alternative Fuel Effects on Contrails and Cruise Emissions (ACCESS) Research Team . Volume 2; Appendices

    Science.gov (United States)

    Kelly, Michael J.

    2013-01-01

    The Alternative Fuel Effects on Contrails and Cruise Emissions (ACCESS) Project Integration Manager requested in July 2012 that the NASA Engineering and Safety Center (NESC) form a team to independently assess aircraft structural failure hazards associated with the ACCESS experiment and to identify potential flight test hazard mitigations to ensure flight safety. The ACCESS Project Integration Manager subsequently requested that the assessment scope be focused predominantly on structural failure risks to the aircraft empennage (horizontal and vertical tail). This report contains the Appendices to Volume I.

  19. Preliminary analysis of three cycles for nuclear propulsion of aircraft

    Science.gov (United States)

    Humble, L V; Wachtl, W W; Doyle, R B

    1950-01-01

    A preliminary study was made of the feasibility of three cycles for nuclear propulsion of aircraft: a direct-air-turbojet, a binary liquid-metal turbojet, and a helium compressor jet. All three cycles appeared feasible for flight at a Mach number of 0.9 and altitudes up to 50,000 feet; the liquid-metal cycle appeared feasible for flight at a Mach number of 1.5. The air and helium cycles resulted in heavier aircraft than did the liquid-metal cycle, particularly at a Mach number of 1.5. The relative advantage of the liquid-metal cycle became greater as the flight speed and altitude increased, and as the reactor wall temperature decreased.

  20. Lagrangian analysis of low altitude anthropogenic plume processing across the North Atlantic

    Directory of Open Access Journals (Sweden)

    E. Real

    2008-12-01

    Full Text Available The photochemical evolution of an anthropogenic plume from the New-York/Boston region during its transport at low altitudes over the North Atlantic to the European west coast has been studied using a Lagrangian framework. This plume, originally strongly polluted, was sampled by research aircraft just off the North American east coast on 3 successive days, and then 3 days downwind off the west coast of Ireland where another aircraft re-sampled a weakly polluted plume. Changes in trace gas concentrations during transport are reproduced using a photochemical trajectory model including deposition and mixing effects. Chemical and wet deposition processing dominated the evolution of all pollutants in the plume. The mean net photochemical O3 production is estimated to be −5 ppbv/day leading to low O3 by the time the plume reached Europe. Model runs with no wet deposition of HNO3 predicted much lower average net destruction of −1 ppbv/day O3, arising from increased levels of NOx via photolysis of HNO3. This indicates that wet deposition of HNO3 is indirectly responsible for 80% of the net destruction of ozone during plume transport. If the plume had not encountered precipitation, it would have reached Europe with O3 concentrations of up to 80 to 90 ppbv and CO between 120 and 140 ppbv. Photochemical destruction also played a more important role than mixing in the evolution of plume CO due to high levels of O3 and water vapour showing that CO cannot always be used as a tracer for polluted air masses, especially in plumes transported at low altitudes. The results also show that, in this case, an increase in O3/CO slopes can be attributed to photochemical destruction of CO and not to photochemical O3 production as is often assumed.

  1. APACHE: Integrated Hybrid Fuel Cell System for 2-Seat All Electric Aircraft Propulsion

    OpenAIRE

    Hordé, Théophile; Achard, Patrick; Metkemeijer, Rudolf

    2012-01-01

    International audience The French APACHE project aims at demonstrating the feasibility of using a Hybrid Fuel Cell System (HFCS) as the power generator for all electric 2-seat aircrafts. This study focuses on three main topics: airworthiness of Proton Exchange Membrane Fuel Cells (PEMFC), their hybridization with Lithium Ion (Li-Ion) batteries and systems' integration into light aircrafts. Altitude and inclination tests have been led and allow to conclude on the ability of PEMFC to operate...

  2. A study of external fuel vaporization. [for aircraft gas turbine engines

    Science.gov (United States)

    Szetela, E. J.; Chiappetta, L.; Baker, C. E.

    1981-01-01

    Candidate external vaporizer designs for an aircraft gas turbine engine are evaluated with respect to fuel thermal stability, integration of the vaporizer system into the aircraft engine, engine and vaporizer dynamic response, startup and altitude restart, engine performance, control requirements, safety, and maintenance. The selected concept is shown to offer potential gains in engine performance in terms of reduced specific fuel consumption and improved engine thrust/weight ratio. The thrust/weight improvement can be traded against vaporization system weight.

  3. Effect of wing flexibility on aircraft flight dynamics

    OpenAIRE

    Qiao, Yuqing

    2012-01-01

    The purpose of this thesis is to give a preliminary investigation into the effect of wing deformation on flight dynamics. The candidate vehicle is FW-11 which is a flying wing configuration aircraft with high altitude and long endurance characteristics. The aeroelastic effect may be significant for this type of configuration. Two cases, the effect of flexible wing on lift distribution and on roll effectiveness during the cruise condition with different inertial parameters are investigated. ...

  4. Cross-Polar Aircraft Trajectory Optimization and Potential Climate Impact

    Science.gov (United States)

    Sridhar, Banavar; Chen, Neil; Ng, Hok

    2011-01-01

    Cross-Polar routes offer new opportunities for air travel markets. Transpolar flights reduce travel times, fuel burns, and associated environmental emissions by flying direct paths between many North American and Asian cities. This study evaluates the potential benefits of flying wind-optimal polar routes and assessed their potential impact on climate change. An optimization algorithm is developed for transpolar flights to generate wind-optimal trajectories that minimize climate impact of aircraft, in terms of global warming potentials (relative to warming by one kg of CO2) of several types of emissions, while avoiding regions of airspace that facilitate persistent contrail formation. Estimations of global warming potential are incorporated into the objective function of the optimization algorithm to assess the climate impact of aircraft emissions discharged at a given location and altitude. The regions of airspace with very low ambient temperature and areas favorable to persistent contrail formation are modeled as undesirable regions that aircraft should avoid and are formulated as soft state constraints. The fuel burn and climate impact of cross-polar air traffic flying various types of trajectory including flightplan, great circle, wind-optimal, and contrail-avoidance are computed for 15 origin-destination pairs between major international airports in the U.S. and Asia. Wind-optimal routes reduce average fuel burn of flight plan routes by 4.4% on December 4, 2010 and 8.0% on August 7, 2010, respectively. The tradeoff between persistent contrail formation and additional global warming potential of aircraft emissions is investigated with and without altitude optimization. Without altitude optimization, the reduction in contrail travel times is gradual with increase in total fuel consumption. When altitude is optimized, a one percent increase in additional global warming potential, a climate impact equivalent to that of 4070kg and 4220kg CO2 emission, reduces 135

  5. Long-range pollution transport during the MILAGRO-2006 campaign: a case study of a major Mexico City outflow event using free-floating altitude-controlled balloons

    Directory of Open Access Journals (Sweden)

    P. B. Voss

    2010-08-01

    Full Text Available One of the major objectives of the Megacities Initiative: Local And Global Research Observations (MILAGRO-2006 campaign was to investigate the long-range transport of polluted Mexico City Metropolitan Area (MCMA outflow and determine its downwind impacts on air quality and climate. Six research aircraft, including the National Center for Atmospheric Research (NCAR C-130, made extensive chemical, aerosol, and radiation measurements above MCMA and more than 1000 km downwind in order to characterize the evolution of the outflow as it aged and dispersed over the Mesa Alta, Sierra Madre Oriental, Coastal Plain, and Gulf of Mexico. As part of this effort, free-floating Controlled-Meteorological (CMET balloons, commanded to change altitude via satellite, made repeated profile measurements of winds and state variables within the advecting outflow. In this paper, we present an analysis of the data from two CMET balloons that were launched near Mexico City on the afternoon of 18 March 2006 and floated downwind with the MCMA pollution for nearly 30 h. The repeating profile measurements show the evolving structure of the outflow in considerable detail: its stability and stratification, interaction with other air masses, mixing episodes, and dispersion into the regional background. Air parcel trajectories, computed directly from the balloon wind profiles, show three transport pathways on 18–19 March: (a high-altitude advection of the top of the MCMA mixed layer, (b mid-level outflow over the Sierra Madre Oriental followed by decoupling and isolated transport over the Gulf of Mexico, and (c low-level outflow with entrainment into a cleaner northwesterly jet above the Coastal Plain. The C-130 aircraft intercepted the balloon-based trajectories three times on 19 March, once along each of these pathways; in all three cases, peaks in urban tracer concentrations and LIDAR backscatter are consistent with MCMA pollution. In comparison with the transport models

  6. Metabolic Effects of High Altitude Trekking in Patients With Type 2 Diabetes

    NARCIS (Netherlands)

    de Mol, Pieter; Fokkert, Marion J.; de Vries, Suzanna T.; de Koning, Eelco J. P.; Dikkeschei, Bert D.; Gans, Rijnold O. B.; Tack, Cees J.; Bilo, Henk J. G.

    2012-01-01

    OBJECTIVE-Limited information is available regarding the metabolic effects of high altitude trekking in patients with type 2 diabetes. RESEARCH DESIGN AND METHODS-Thirteen individuals with type 2 diabetes took part, in a 12-day expedition to the summit of Mount Toubkal (altitude, 4,167 m), Morocco,

  7. 大型民机企业人力资源能力建设评价研究*%Research on Human Resource Construction Evaluation of Large Aircraft Corporation

    Institute of Scientific and Technical Information of China (English)

    杨生斌; 孙振杰; 孔莹

    2013-01-01

    Large aircraft corporations need strong human resources to support,in view of "I am the Lord", "the Lord manufacturers and suppliers" develop-ment model in China's large aircraft corporations, the importance of corporations internal human resources con-struction is indicated. Through using the benchmarking corporations Boeing and Airbus company human resource practices, from investment, performance and output three aspects, the large aircraft corporations human resources construction evaluation index system and evaluation model are constructed so as to improve human resources con-struction standard of large aircraft corporations in China.%大型民机企业需要强有力的人力资源做支撑,针对我国大型民机企业“以我为主”、“主制造商+供应商”的发展模式,明确企业内部人力资源能力建设的重要性。通过借鉴标杆企业波音和空客的人力资源实践,从投入、表现和产出3方面入手构建了大型民机企业人力资源能力建设评价指标体系和评价模型,以期促进我国大型民机企业人力资源能力不断提升。

  8. Cable Tensiometer for Aircraft

    Science.gov (United States)

    Nunnelee, Mark (Inventor)

    2008-01-01

    The invention is a cable tensiometer that can be used on aircraft for real-time, in-flight cable tension measurements. The invention can be used on any aircraft cables with high precision. The invention is extremely light-weight, hangs on the cable being tested and uses a dual bending beam design with a high mill-volt output to determine tension.

  9. Rocket Engine Altitude Simulation Technologies

    Science.gov (United States)

    Woods, Jody L.; Lansaw, John

    2010-01-01

    John C. Stennis Space Center is embarking on a very ambitious era in its rocket engine propulsion test history. The first new large rocket engine test stand to be built at Stennis Space Center in over 40 years is under construction. The new A3 Test Stand is designed to test very large (294,000 Ibf thrust) cryogenic propellant rocket engines at a simulated altitude of 100,000 feet. A3 Test Stand will have an engine testing chamber where the engine will be fired after the air in the chamber has been evacuated to a pressure at the simulated altitude of less than 0.16 PSIA. This will result in a very unique environment with extremely low pressures inside a very large chamber and ambient pressures outside this chamber. The test chamber is evacuated of air using a 2-stage diffuser / ejector system powered by 5000 lb/sec of steam produced by 27 chemical steam generators. This large amount of power and flow during an engine test will result in a significant acoustic and vibrational environment in and around A3 Test Stand.

  10. D-558-2 being mounted to P2B-1S launch aircraft in hangar

    Science.gov (United States)

    1954-01-01

    . Champine and John H. Griffith flew 21 times in this configuration to test airspeed calibrations and to research longitudinal and lateral stability and control. In the process, during August of 1949 they encountered pitch-up problems, which NACA engineers recognized as serious because they could produce a limiting and dangerous restriction on flight performance. Hence, they determined to make a complete investigation of the problem. In 1950, Douglas replaced the turbojet with an LR-8 rocket engine, and its pilot, William B. Bridgeman, flew the aircraft seven times up to a speed of Mach 1.88 (1.88 times the speed of sound) and an altitude of 79,494 feet (the latter an unofficial world's altitude record at the time, achieved on August 15, 1951). In the rocket configuration, a Navy P2B (Navy version of the B-29) launched the airplane at approximately 30,000 feet after taking off from the ground with the Skyrocket attached beneath its bomb bay. During Bridgeman's supersonic flights, he encountered a violent rolling motion known as lateral instability that was less pronounced on the Mach 1.88 flight on August 7, 1951, than on a Mach 1.85 flight in June when he pushed over to a low angle of attack (angle of the fuselage or wing to the prevailing wind direction). The NACA engineers studied the behavior of the aircraft before beginning their own flight research in the airplane in September 1951. Over the next couple of years, NACA pilot A. Scott Crossfield flew the airplane 20 times to gather data on longitudinal and lateral stability and control, wing and tail loads, and lift, drag, and buffeting characteristics at speeds up to Mach 1.878. At that point, Marine Lt. Col. Marion Carl flew the airplane to a new (unofficial) altitude record of 83,235 feet on August 21, 1953, and to a maximum speed of Mach 1.728. Following Carl's completion of these flights for the Navy, NACA technicians at the High-Speed Flight Research Station (HSFRS) near Mojave, Calif., outfitted the LR-8 engine

  11. High-Altitude Platforms - Present Situation and Technology Trends

    Directory of Open Access Journals (Sweden)

    Flavio Araripe D'Oliveira

    2016-07-01

    Full Text Available High-altitude platforms (HAPs are aircraft, usually unmanned airships or airplanes positioned above 20 km, in the stratosphere, in order to compose a telecommunications network or perform remote sensing. In the 1990 and 2000 decades, several projects were launched, but very few had continued. In 2014, 2 major Internet companies (Google and Facebook announced investments in new HAP projects to provide Internet access in regions without communication infrastructure (terrestrial or satellite, bringing back attention to the development of HAP. This article aims to survey the history of HAPs, the current state-of-the-art (April 2016, technology trends and challenges. The main focus of this review will be on technologies directly related to the aerial platform, inserted in the aeronautical engineering field of knowledge, not detailing aspects of the telecommunications area.

  12. Research of moving distance measurement and display in aircraft docking system%飞机泊位系统中移动距离测量与显示的研究

    Institute of Scientific and Technical Information of China (English)

    张积洪; 马创

    2011-01-01

    研究一种飞机泊位过程中基于多传感器的飞机移动距离测量与显示系统,该系统采用单片机、激光对射式传感器、优先编码器、LED显示屏等器件,实现了在飞机泊位过程中对飞机移动距离的测量,将测量结果通过单片机处理并传输给移动距离显示屏进行显示.此系统可为飞行员提供清晰的飞机移动距离信息,进而实现引导飞机停靠的功能.%A kind of moving distance measurement and display system in the process of aircraft docking based on multi-sensor technology was researched. The system adopts elements as SCM, correlative laser sensor, priority encoder, LED screens and other devices, allowing to measure the moving distance of aircraft in the process of aircraft docking. The measured results processed by SCM were transferred to display screen to indicate in the progress bar. The system can provide clear dynamic progress information for pilots , and realize the function of docking guidance.

  13. 民用飞机研制项目风险管理研究与应用%Research and Application of Risk Management in Civil Aircraft Development Project

    Institute of Scientific and Technical Information of China (English)

    卢新来; 丁常宏; 任长伟; 于晓伟

    2015-01-01

    民用飞机研制项目具有技术含量高、难度大、复杂度高、高投入、高风险、不确定性大等特点,在项目管理中引入风险管理对项目的顺利推进具有重要意义。在研究风险管理理论和流程的基础上,提出了民用飞机研制项目的风险识别方法和量化评估方法,建立了风险管理的组织结构和运行流程,给出了风险管理平台的系统架构和技术实现,开发的系统可用于民用飞机研制项目风险管理。%There are high technical content, dififcult and highly complex, high input, high risks, uncertainties and other great features in civil aircraft development project. Bringing risk management in civil aircraft development project has important signiifcance for project development. Based on researching the theory and procedure of risk management, the methods of risk identification and quantitative assessment in civil aircraft development project was presented, organizational structure and operation process of risk management was established. An architecture framework of risk management system, together with its implementation was proposed, and the developed system was applied in risk management of civil aircraft development project.

  14. D-558-2 being mounted to P2B-1S launch aircraft

    Science.gov (United States)

    1953-01-01

    to test airspeed calibrations and to research longitudinal and lateral stability and control. In the process, during August of 1949 they encountered pitch-up problems, which NACA engineers recognized as serious because they could produce a limiting and dangerous restriction on flight performance. Hence, they determined to make a complete investigation of the problem. In 1950, Douglas replaced the turbojet with an LR-8 rocket engine, and its pilot, William B. Bridgeman, flew the aircraft seven times up to a speed of Mach 1.88 (1.88 times the speed of sound) and an altitude of 79,494 feet (the latter an unofficial world's altitude record at the time, achieved on August 15, 1951). In the rocket configuration, a Navy P2B (Navy version of the B-29) launched the airplane at approximately 30,000 feet after taking off from the ground with the Skyrocket attached beneath its bomb bay. During Bridgeman's supersonic flights, he encountered a violent rolling motion known as lateral instability that was less pronounced on the Mach 1.88 flight on August 7, 1951, than on a Mach 1.85 flight in June when he pushed over to a low angle of attack (angle of the fuselage or wing to the prevailing wind direction). The NACA engineers studied the behavior of the aircraft before beginning their own flight research in the airplane in September 1951. Over the next couple of years, NACA pilot A. Scott Crossfield flew the airplane 20 times to gather data on longitudinal and lateral stability and control, wing and tail loads, and lift, drag, and buffeting characteristics at speeds up to Mach 1.878. At that point, Marine Lt. Col. Marion Carl flew the airplane to a new (unofficial) altitude record of 83,235 feet on August 21, 1953, and to a maximum speed of Mach 1.728. Following Carl's completion of these flights for the Navy, NACA technicians at the High-Speed Flight Research Station (HSFRS) near Mojave, Calif., outfitted the LR-8 engine's cylinders with nozzle extensions to prevent the exhaust gas

  15. Dedicated Solutions for Structural Health Monitoring of Aircraft Components

    OpenAIRE

    Pitropakis, Ioannis

    2015-01-01

    Aircraft structures, like any other mechanical structure, are subjected to various external factors that influence their lifetime. Mechanicalnbsp;and the environment are only some of the factors that can degrade the structure of aircraft components. Monitoring of these degradations by regular inspections or automated data recording is vital for the structural health of the critical components of an aircraft. This research proposes a number of dedicated solutions for structural health monitori...

  16. Control Design for a Generic Commercial Aircraft Engine

    Science.gov (United States)

    Csank, Jeffrey; May, Ryan D.

    2010-01-01

    This paper describes the control algorithms and control design process for a generic commercial aircraft engine simulation of a 40,000 lb thrust class, two spool, high bypass ratio turbofan engine. The aircraft engine is a complex nonlinear system designed to operate over an extreme range of environmental conditions, at temperatures from approximately -60 to 120+ F, and at altitudes from below sea level to 40,000 ft, posing multiple control design constraints. The objective of this paper is to provide the reader an overview of the control design process, design considerations, and justifications as to why the particular architecture and limits have been chosen. The controller architecture contains a gain-scheduled Proportional Integral controller along with logic to protect the aircraft engine from exceeding any limits. Simulation results illustrate that the closed loop system meets the Federal Aviation Administration s thrust response requirements

  17. Application of variable-sweep wings to commuter aircraft

    Science.gov (United States)

    Robins, A. W.; Beissner, F. L., Jr.; Lovell, W. A.; Price, J. E.; Turriiziani, R. V.; Washburn, F. F.

    1983-01-01

    The effects of using variable-sweep wings on the riding quality and mission-performance characteristics of commuter-type aircraft were studied. A fixed-wing baseline vehicle and a variable-sweep version of the baseline were designed and evaluated. Both vehicles were twin-turboprop, pressurized-cabin, 30-passenger commuter aircraft with identical mission requirements. Mission performance was calculated with and without various ride-quality constraints for several combinations of cruise altitude and stage lengths. The variable-sweep aircraft had a gross weight of almost four percent greater than the fixed-wing baseline in order to meet the design-mission requirements. In smooth air, the variable sweep configuration flying with low sweep had a two to three percent fuel-use penalty. However, the imposition of quality constraints in rough air can result in advantages in both fuel economy and flight time for the variable-sweep vehicle flying with high sweep.

  18. Economy of Adaptation to High Altitude

    Institute of Scientific and Technical Information of China (English)

    Jean-Paul Richalet

    2004-01-01

    @@ The international meeting that will be held in Xining and Lhasa in August 2004 will be a wonderful occasion to share facts and concepts dealing with adaptation to high altitude. Life at high altitude is a challenge for thousands of animal species and millions of humans residing or visiting high altitude regions of the world. To try to understand the physiological mechanisms involved in the adaptation processes to high altitude hypoxia, it is convenient to start by defining what is "extreme" from a biological point of view.

  19. Aspirated Compressors for High Altitude Engines Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Aurora Flight Sciences proposes to incorporate aspirated compressor technology into a high altitude, long endurance (HALE) concept engine. Aspiration has been...

  20. On the effect of emissions from aircraft engines on the state of the atmosphere

    Directory of Open Access Journals (Sweden)

    U. Schumann

    Full Text Available Emissions from aircraft engines include carbon dioxide, water vapour, nitrogen oxides, sulphur components and various other gases and particles. Such emissions from high-flying global civil subsonic air traffic may cause anthropogenic climate changes by an increase of ozone and cloudiness in the upper troposphere, and by an enhanced greenhouse effect. The absolute emissions by air traffic are small (a few percent of the total compared to surface emissions. However, the greenhouse effect of emitted water and of nitrogen oxides at cruise altitude is potentially large compared to that of the same emissions near the earth's surface because of relatively large residence times at flight altitudes, low background concentrations, low temperature, and large radiative efficiency. Model computations indicate that emission of nitrogen oxides has doubled the background concentration in the upper troposphere between 40°N and 60°N. Models also indicate that this causes an increase of ozone by about 5-20%. Regionally, the observed annual mean change in cloudiness is 0.4%. It is estimated that the resultant greenhouse effect of changes in ozone and thin cirrus cloud cover causes a climatic surface temperature change of 0.01-0.1 K. These temperature changes are small compared to the natural variability. Recent research indicates that the emissions at cruise altitude may increase the amount of stratospheric aerosols and polar stratospheric clouds and thereby have an impact on the atmospheric environment. Air traffic is increasing about 5-6% per year, fuel consumption by about 3%, hence the effects of the related emissions are expected to grow. This paper surveys the state of knowledge and describes several results from recent and ongoing research.

  1. Physical Body Impact After High Altitude Bail-out

    Institute of Scientific and Technical Information of China (English)

    CHEN Xiaopeng; GUAN Huanwen; ZHUO Congshan; FENG Wenchun; ZHONG Chengwen

    2011-01-01

    In most of the emergency circumstances, the aircrew leaves the aircraft under unsatisfied conditions, such as too high relative velocity to the ambient air or Iow partial oxygen pressure. The aircrew must pass through this area as quickly as possible before opening the parachute safely, viz., free-fall. Numerical simulations are conducted in this paper to explore the major characteristics of the aircrew free-fall process by using a commercial computational fluid dynamic (CFD) software, FLUENT. Coupled with the classical pressure-altitude and temperature-altitude relations, Navier-Stokes (N-S) equations for compressible flow are solved by using finite volume method. The body velocity and the attitude are predicted with six-degree of freedom (6DOF) module. The evolution of velocities, including horizontal, vertical components and angular velocity, is obtained. It is also analyzed further according to the particle kinetic theories. It is validated that the theories can predict the process qualitatively well with a modified drag effect, which mainly stems from the velocity pressure. An empirical modification factor is proposed according to the fitting results.

  2. Wilderness medicine at high altitude: recent developments in the field

    Directory of Open Access Journals (Sweden)

    Shah NM

    2015-09-01

    Full Text Available Neeraj M Shah,1 Sidra Hussain,2 Mark Cooke,3 John P O’Hara,3 Adrian Mellor3,4 1Division of Asthma, Allergy and Lung Biology, King’s College London, UK; 2School of Medicine, University College London, London, UK; 3Research Institute for Sport, Physical Activity and Leisure, Leeds Beckett University, Leeds, UK; 4Academic Department of Military Anaesthesia and Critical Care, Royal Centre for Defence Medicine, Birmingham, UK Abstract: Travel to high altitude is increasingly popular. With this comes an increased incidence of high-altitude illness and therefore an increased need to improve our strategies to prevent and accurately diagnose these. In this review, we provide a summary of recent advances of relevance to practitioners who may be advising travelers to altitude. Although the Lake Louise Score is now widely used as a diagnostic tool for acute mountain sickness (AMS, increasing evidence questions the validity of doing so, and of considering AMS as a single condition. Biomarkers, such as brain natriuretic peptide, are likely correlating with pulmonary artery systolic pressure, thus potential markers of the development of altitude illness. Established drug treatments include acetazolamide, nifedipine, and dexamethasone. Drugs with a potential to reduce the risk of developing AMS include nitrate supplements, propagators of nitric oxide, and supplemental iron. The role of exercise in the development of altitude illness remains hotly debated, and it appears that the intensity of exercise is more important than the exercise itself. Finally, despite copious studies demonstrating the value of preacclimatization in reducing the risk of altitude illness and improving performance, an optimal protocol to preacclimatize an individual remains elusive. Keywords: hypoxia, acute mountain sickness, acclimatization, biomarkers, preacclimatization

  3. Process analysis of the modelled 3-D mesoscale impact of aircraft emissions on the atmosphere

    Energy Technology Data Exchange (ETDEWEB)

    Hendricks, J.; Ebel, A.; Lippert, E.; Petry, H. [Koeln Univ. (Germany). Inst. fuer Geophysik und Meterorologie

    1997-12-31

    A mesoscale chemistry transport model is applied to study the impact of aircraft emissions on the atmospheric trace gas composition. A special analysis of the simulations is conducted to separate the effects of chemistry, transport, diffusion and cloud processes on the transformation of the exhausts of a subsonic fleet cruising over the North Atlantic. The aircraft induced ozone production strongly depends on the tropopause height and the cruise altitude. Aircraft emissions may undergo an effective downward transport under the influence of stratosphere-troposphere exchange activity. (author) 12 refs.

  4. Aircraft emission inventories for scheduled air traffic for the 1976-92 time period. Historical trends

    Energy Technology Data Exchange (ETDEWEB)

    Baughcum, S.L.; Henderson, S.C.; Tritz, T.G. [Boeing Co., Seattle, WA (United States)

    1997-12-31

    Emission inventories of fuel burned, NO{sub x}, CO, and hydrocarbons have been calculated for scheduled air traffic in 1976, 1984, 1990 and 1992 on a 1 deg latitude x 1 deg longitude x 1 km pressure altitude grid. Using this database, the seasonal variation and historical trends in aircraft emissions have been calculated for selected geographical regions (e.g., North Atlantic, Europe, North America, North Pacific). The trend in emissions is a combination of the effects of passenger demand growth, improved aircraft efficiency, changes in combustor characteristics, and aircraft size. (author) 8 refs.

  5. NASA/DOD Aerospace Knowledge Diffusion Research Project. Paper 59: Japanese Technological Innovation. Implications for Large Commercial Aircraft and Knowledge Diffusion

    Science.gov (United States)

    Pinelli, Thomas E.; Barclay, Rebecca O.; Kotler, Mindy L.

    1997-01-01

    This paper explores three factors-public policy, the Japanese (national) innovation system, and knowledge-that influence technological innovation in Japan. To establish a context for the paper, we examine Japanese culture and the U.S. and Japanese patent systems in the background section. A brief history of the Japanese aircraft industry as a source of knowledge and technology for other industries is presented. Japanese and U.S. alliances and linkages in three sectors-biotechnology, semiconductors, and large commercial aircraft (LCA)-and the importation, absorption, and diffusion of knowledge and technology are examined next. The paper closes with implications for diffusing knowledge and technology, U.S. public policy, and LCA.

  6. Research situation of multiple site damages aircraft structure%飞机结构多处损伤研究现状

    Institute of Scientific and Technical Information of China (English)

    李郑琦; 胡建军; 陈跃良

    2011-01-01

    多损伤是老龄飞机最主要的损伤形式,在文中介绍了多损伤应力强度因子的计算方法和多裂纹连通准则,飞机结构多损伤裂纹扩展模型和可靠性分析研究现状.%Multiple site damages (MSD) is the major aging damage forms of aircraft. It was introduced Calculation method of damage stress intensity factor and crack connected criteria for aircraft structure were introduced in this paper, and MSD crack propagation model and situation of its reliability analysis were also presented.

  7. SOLAR AIRCRAFT DESIGN

    OpenAIRE

    RAHMATI, Sadegh; GHASED, Amir

    2015-01-01

    Abstract. Generally domain Aircraft uses conventional fuel. These fuel having limited life, high cost and pollutant. Also nowadays price of petrol and other fuels are going to be higher, because of scarcity of those fuels. So there is great demand of use of non-exhaustible unlimited source of energy like solar energy. Solar aircraft is one of the ways to utilize solar energy. Solar aircraft uses solar panel to collect the solar radiation for immediate use but it also store the remaining part ...

  8. U.S. Geological Survey Emerging Applications of Unmanned Aircraft Systems

    Science.gov (United States)

    Hutt, M. E.

    2012-12-01

    In anticipation of transforming the research methods and resource management techniques employed across the Department of the Interior, the U.S. Geological Survey (USGS) Unmanned Aircraft Systems (UAS) Project Office is conducting missions using small UAS- sUAS platforms (logistically difficult, cost prohibitive or technically impossible to obtain consistent, reliable, timely information. USGS is teaming with the Department of the Interior Aviation Management Directorate to ensure the safe and cost effective adoption of UAS technology. While the USGS is concentrating on operating sUAS, the immense value of increased flight time and more robust sensor capabilities available on larger platforms cannot be ignored. We are partnering with several groups including the Department of Homeland Security, National Aeronautics and Space Administration, Department of Defense, and National Oceanic and Atmospheric Administration for access to data collected from their fleet of high altitude, long endurance (HALE) UAS. The HALE systems include state of the art sensors including Electro-Optical, Thermal Infrared and Synthetic Aperture Radar (SAR). The data being collected by High Altitude, Long Endurance (HALE) systems is can be routinely shared in near real time at several DOI- USGS locations. Analysis tools are becoming available that can produce a robust set of products including a geo-referenced base for value added investigations. Much like the use of global positioning systems, unmanned aircraft systems have the potential of enabling us to be better stewards of the land. We are actively working to develop applications of the traditional full motion video capabilities and are engaged in developing additional sensor capabilities for sUAS including- magnetometers, temperature, radio telemetry, chemical and biological gas detection, and gimbal mounted "photogrammetric" cameras.

  9. 关于某型飞机客舱舷窗组件设计的分析与研究%The Analysis and Research on the Design of the Aircraft's Cabin Window

    Institute of Scientific and Technical Information of China (English)

    罗腾腾

    2012-01-01

    Composite material can be sibly can be used on the cabin window s cabin window. designed and composite structures have less wei Dtailed analysises and particularly researches on t, composite material pos- the design of the aircraft'%复合材料有着良好的可设计性和减重性能,客舱舷窗组件也在积极探索应用复合材料的可能。详细分析和探讨了某型飞机客舱舷窗组件的设计。

  10. Solar Cell Short Circuit Current Errors and Uncertainties During High Altitude Calibrations

    Science.gov (United States)

    Snyder, David D.

    2012-01-01

    High altitude balloon based facilities can make solar cell calibration measurements above 99.5% of the atmosphere to use for adjusting laboratory solar simulators. While close to on-orbit illumination, the small attenuation to the spectra may result in under measurements of solar cell parameters. Variations of stratospheric weather, may produce flight-to-flight measurement variations. To support the NSCAP effort, this work quantifies some of the effects on solar cell short circuit current (Isc) measurements on triple junction sub-cells. This work looks at several types of high altitude methods, direct high altitude meas urements near 120 kft, and lower stratospheric Langley plots from aircraft. It also looks at Langley extrapolation from altitudes above most of the ozone, for potential small balloon payloads. A convolution of the sub-cell spectral response with the standard solar spectrum modified by several absorption processes is used to determine the relative change from AMO, lscllsc(AMO). Rayleigh scattering, molecular scatterin g from uniformly mixed gases, Ozone, and water vapor, are included in this analysis. A range of atmosph eric pressures are examined, from 0. 05 to 0.25 Atm to cover the range of atmospheric altitudes where solar cell calibrations a reperformed. Generally these errors and uncertainties are less than 0.2%

  11. Using a Convection Model to Predict Altitudes of White Stork Migration Over Central Israel

    Science.gov (United States)

    Shamoun-Baranes, Judy; Liechti, Olivier; Yom-Tov, Yoram; Leshem, Yossi

    Soaring migrants such as storks, pelicans and large birds of prey rely on thermal convection during migration. The convection model ALPTHERM was designed to predict the onset, strength, duration and depth of thermal convection for varying topographies for glider pilots, based on atmospheric conditions at midnight. We tested ALPTHERM predictions as configured for two topographies of central Israel, the Coastal Plains and the Judean and Samarian Mountains in order to predict altitudes of migrating white storks (Ciconia ciconia). Migrating flocks of white storks were tracked with a motorized glider, to measure maximum altitudes of migration during spring 2000. A significant positive correlation was found between the maximum daily altitudes of migration measured and the predicted upper boundary of thermal convection for the Coastal Plains and Samarian Mountains. Thirty-minute predictions for the Coastal Plains and Samarian Mountains correlated positively with measured maximum migration altitudes per thermal. ALPTHERM forecasts can be used to alter flight altitudes in both civil and especially military aviation and reduce the hazard of serious aircraft collisions with soaring migrants.

  12. Parabolic aircraft solidification experiments

    Science.gov (United States)

    Workman, Gary L. (Principal Investigator); Smith, Guy A.; OBrien, Susan

    1996-01-01

    A number of solidification experiments have been utilized throughout the Materials Processing in Space Program to provide an experimental environment which minimizes variables in solidification experiments. Two techniques of interest are directional solidification and isothermal casting. Because of the wide-spread use of these experimental techniques in space-based research, several MSAD experiments have been manifested for space flight. In addition to the microstructural analysis for interpretation of the experimental results from previous work with parabolic flights, it has become apparent that a better understanding of the phenomena occurring during solidification can be better understood if direct visualization of the solidification interface were possible. Our university has performed in several experimental studies such as this in recent years. The most recent was in visualizing the effect of convective flow phenomena on the KC-135 and prior to that were several successive contracts to perform directional solidification and isothermal casting experiments on the KC-135. Included in this work was the modification and utilization of the Convective Flow Analyzer (CFA), the Aircraft Isothermal Casting Furnace (ICF), and the Three-Zone Directional Solidification Furnace. These studies have contributed heavily to the mission of the Microgravity Science and Applications' Materials Science Program.

  13. Aircraft Fire Protection Laboratory

    Data.gov (United States)

    Federal Laboratory Consortium — The Navy Aircraft Protection Laboratory provides complete test support for all Navy air vehicle fire protection systems. The facility allows for the simulation of a...

  14. Solar thermal aircraft

    Science.gov (United States)

    Bennett, Charles L.

    2007-09-18

    A solar thermal powered aircraft powered by heat energy from the sun. A heat engine, such as a Stirling engine, is carried by the aircraft body for producing power for a propulsion mechanism, such as a propeller. The heat engine has a thermal battery in thermal contact with it so that heat is supplied from the thermal battery. A solar concentrator, such as reflective parabolic trough, is movably connected to an optically transparent section of the aircraft body for receiving and concentrating solar energy from within the aircraft. Concentrated solar energy is collected by a heat collection and transport conduit, and heat transported to the thermal battery. A solar tracker includes a heliostat for determining optimal alignment with the sun, and a drive motor actuating the solar concentrator into optimal alignment with the sun based on a determination by the heliostat.

  15. Depreciation of aircraft

    Science.gov (United States)

    Warner, Edward P

    1922-01-01

    There is a widespread, and quite erroneous, impression to the effect that aircraft are essentially fragile and deteriorate with great rapidity when in service, so that the depreciation charges to be allowed on commercial or private operation are necessarily high.

  16. Aircraft electromagnetic compatibility

    Science.gov (United States)

    Clarke, Clifton A.; Larsen, William E.

    1987-01-01

    Illustrated are aircraft architecture, electromagnetic interference environments, electromagnetic compatibility protection techniques, program specifications, tasks, and verification and validation procedures. The environment of 400 Hz power, electrical transients, and radio frequency fields are portrayed and related to thresholds of avionics electronics. Five layers of protection for avionics are defined. Recognition is given to some present day electromagnetic compatibility weaknesses and issues which serve to reemphasize the importance of EMC verification of equipment and parts, and their ultimate EMC validation on the aircraft. Proven standards of grounding, bonding, shielding, wiring, and packaging are laid out to help provide a foundation for a comprehensive approach to successful future aircraft design and an understanding of cost effective EMC in an aircraft setting.

  17. Jupiter's High-Altitude Clouds

    Science.gov (United States)

    2007-01-01

    The New Horizons Multispectral Visible Imaging Camera (MVIC) snapped this incredibly detailed picture of Jupiter's high-altitude clouds starting at 06:00 Universal Time on February 28, 2007, when the spacecraft was only 2.3 million kilometers (1.4 million miles) from the solar system's largest planet. Features as small as 50 kilometers (30 miles) are visible. The image was taken through a narrow filter centered on a methane absorption band near 890 nanometers, a considerably redder wavelength than what the eye can see. Images taken through this filter preferentially pick out clouds that are relatively high in the sky of this gas giant planet because sunlight at the wavelengths transmitted by the filter is completely absorbed by the methane gas that permeates Jupiter's atmosphere before it can reach the lower clouds. The image reveals a range of diverse features. The south pole is capped with a haze of small particles probably created by the precipitation of charged particles into the polar regions during auroral activity. Just north of the cap is a well-formed anticyclonic vortex with rising white thunderheads at its core. Slightly north of the vortex are the tendrils of some rather disorganized storms and more pinpoint-like thunderheads. The dark 'measles' that appear a bit farther north are actually cloud-free regions where light is completely absorbed by the methane gas and essentially disappears from view. The wind action considerably picks up in the equatorial regions where giant plumes are stretched into a long wave pattern. Proceeding north of the equator, cirrus-like clouds are shredded by winds reaching speeds of up to 400 miles per hour, and more pinpoint-like thunderheads are visible. Although some of the famous belt and zone structure of Jupiter's atmosphere is washed out when viewed at this wavelength, the relatively thin North Temperate Belt shows up quite nicely, as does a series of waves just north of the belt. The north polar region of Jupiter in

  18. Fine aerosol bulk composition measured on WP-3D research aircraft in vicinity of the Northeastern United States – results from NEAQS

    Directory of Open Access Journals (Sweden)

    C. Warneke

    2007-02-01

    Full Text Available During the New England Air Quality Study (NEAQS in the summer of 2004, airborne measurements were made of the major inorganic ions and the water-soluble organic carbon (WSOC of the submicron (PM1.0 aerosol. These and ancillary data are used to describe the overall aerosol chemical characteristics encountered during the study. Fine particle mass was estimated from particle volume and a calculated density based on measured particle composition. Fine particle organic matter (OM was estimated from WSOC and a mass balance analysis. The aerosol over the northeastern United States (U.S. and Canada was predominately sulfate and associated ammonium, and organic components, although in unique plumes additional ionic components were also periodically above detection limits. In power generation regions, and especially in the Ohio River Valley region, the aerosol tended to be predominantly sulfate (~60% μg μg−1 and apparently acidic, based on an excess of measured anions compared to cations. In all other regions where sulfate concentrations were lower and a smaller fraction of overall mass, the cations and anions were balanced suggesting a more neutral aerosol. In contrast, the WSOC and estimated OM were more spatially uniform and the fraction of OM relative to PM mass largely influenced by sources of sulfate. The study median OM mass fraction was 40%. Throughout the study region, sulfate and organic aerosol mass were highest near the surface and decreased rapidly with increasing altitude. The relative fraction of organic mass to sulfate was similar within the boundary layer (altitude less than ~2.5 km, but was significantly higher in the free troposphere (above ~2.5 km. A number of distinct biomass burning plumes from fires in Alaska and the Yukon were periodically intercepted, mostly at altitudes between 3 and 4 km. These plumes were associated with highest aerosol concentrations of the study and were largely comprised of organic aerosol components

  19. A Grounded Theory Study of Aircraft Maintenance Technician Decision-Making

    Science.gov (United States)

    Norcross, Robert

    Aircraft maintenance technician decision-making and actions have resulted in aircraft system errors causing aircraft incidents and accidents. Aircraft accident investigators and researchers examined the factors that influence aircraft maintenance technician errors and categorized the types of errors in an attempt to prevent similar occurrences. New aircraft technology introduced to improve aviation safety and efficiency incur failures that have no information contained in the aircraft maintenance manuals. According to the Federal Aviation Administration, aircraft maintenance technicians must use only approved aircraft maintenance documents to repair, modify, and service aircraft. This qualitative research used a grounded theory approach to explore the decision-making processes and actions taken by aircraft maintenance technicians when confronted with an aircraft problem not contained in the aircraft maintenance manuals. The target population for the research was Federal Aviation Administration licensed aircraft and power plant mechanics from across the United States. Nonprobability purposeful sampling was used to obtain aircraft maintenance technicians with the experience sought in the study problem. The sample population recruitment yielded 19 participants for eight focus group sessions to obtain opinions, perceptions, and experiences related to the study problem. All data collected was entered into the Atlas ti qualitative analysis software. The emergence of Aircraft Maintenance Technician decision-making themes regarding Aircraft Maintenance Manual content, Aircraft Maintenance Technician experience, and legal implications of not following Aircraft Maintenance Manuals surfaced. Conclusions from this study suggest Aircraft Maintenance Technician decision-making were influenced by experience, gaps in the Aircraft Maintenance Manuals, reliance on others, realizing the impact of decisions concerning aircraft airworthiness, management pressures, and legal concerns

  20. Vertical mixing of commercial aviation emissions from cruise altitude to the surface

    Science.gov (United States)

    Whitt, D. B.; Jacobson, M. Z.; Wilkerson, J. T.; Naiman, A. D.; Lele, S. K.

    2011-07-01

    Data analysis and numerical simulations were used to examine vertical transport of cruise-altitude commercial aircraft emissions to the surface. First, aircraft emission data were compared with static stability and potential temperature data from satellites. Second, we ran global 3-D simulations of a passive tracer released uniformly at 11 km (cruise altitude). We present global, regional, and seasonal results of the data comparisons as well as approximate time scales of vertical mixing derived from the simulations. Using the year 2006 as a case study, we found that 24% of all global commercial aviation emissions occurred in the stratosphere, 17% occurred both north of 40° N and above the 330 K isentrope, and 54% occurred in regions of at least moderate static stability (N2 > 10-4 s-2). In addition, 74% of emissions in the Arctic Circle were in the stratosphere. In the 3-D simulations, the globally averaged tracer-plume e-folding lifetime against vertical transport to any other altitude was 16 days during January and 14 days during July. Furthermore, the passive tracer took 15 days longer in January (77 days) compared with July (62 days) to achieve a surface-to-cruise mixing ratio fraction greater than 0.5 at all latitudes. The dynamical mixing time scales of extratropical cruise-altitude emissions were significantly longer than the globally averaged wet removal time of 4-5 days for aerosol particles emitted in the lower troposphere. Thus, it is unlikely that cruise-altitude emissions affect surface air quality via transport alone outside the tropics.

  1. Anthropometric and body composition changes during expeditions at high altitude.

    Science.gov (United States)

    Zaccagni, Luciana; Barbieri, Davide; Cogo, Annalisa; Gualdi-Russo, Emanuela

    2014-06-01

    The purpose of this study is to investigate separately in the two sexes the physical adaptations associated to exposure to high altitude in a sample of 18 nonacclimatized Caucasian subjects (10 males and 8 females, 22-59 years) who participated to scientific expeditions to Himalaya up to the Pyramid Laboratory (5050 m, Nepal) or Everest North Base Camp (5300 m, Tibet). Anthropometric traits (body height and weight, eight girths and six skinfolds) were collected according to standard procedures, before departure at sea level, during ascent (at altitude > 4000 m above sea level), and after return to low altitude. Body composition was assessed by means of the skinfold method. Both sexes lost on average 4.0% of initial body mass, corresponding to 7.6% of fat mass and 3.5% of fat free mass in males, and to 5.0% of fat mass and 3.6% of fat free mass in females. Average fat mass loss was greater in males than in females. Initial fat mass percentage was positively correlated to fat mass loss and negatively to FFM loss in males only, thus at HA leanest subjects lost more FFM and less FM than the fattest ones. Adaptations were faster in males than in females. In conclusion, the present research describes significant adaptations to high altitude, in terms of body weight reduction, regardless of the amount of performed physical activity. PMID:24665979

  2. Aircraft measurements of gases pollutants and particles during CAREBeijing-2008: distributions, characteristics and influencing factors

    Science.gov (United States)

    Zhang, W.; Zhu, T.; Yang, W.; Bai, Z.; Sun, Y. L.; Xu, Y.; Yin, B.

    2013-01-01

    Measurements of gaseous pollutants, including ozone (O3), sulfur dioxide (SO2), nitrogen oxides (NOx = NO + NO2), carbon monoxide (CO), particle number concentrations (5.6-560 nm and 0.47-30 μm), and meteorological parameters (T, RH, P) were conducted during the Program of Campaigns of Air Quality Research in Beijing and Surrounding Region (CAREBeijing) from 27 August through 13 October 2008. The data of total 18 flights (70 h flight time) from the ground to 2100 m were obtained by a Yun-12 aircraft in the southern surrounded areas of Beijing (38° N-40° N, 114° E-118° E). This measurement was to characterize the regional variation of air pollution during and after the Olympics of 2008, the impacts of different transport direction and possible influencing factors. Results suggested that four different groups of transport sources influenced the pollution level of pollutants with the consideration of the backward trajectory analysis, including: (1) the pollutant transport of the southern direction with higher pollutants level; (2) the cleaner long-range transport of the northern or northwestern direction with lower pollutants level; (3) the transport from the eastern direction with characteristics of sea sources, i.e. middle level of gases pollutants and higher particle concentration; (4) the transport of mixing directions, i.e. lower altitudes from the pollutant transport direction or local pollution but higher altitudes from the clean transport direction. Additionally, the relatively long-lived CO was shown to be a possible transport tracer of long-range transport of northwestern direction especially on the higher altitudes. Three factors influenced the size distribution of particles, i.e. air mass transport direction, ground source emissions and meteorological influences were also discussed.

  3. Research on the active steering control of an aircraft tractor%飞机牵引车自动转向控制

    Institute of Scientific and Technical Information of China (English)

    王能建; 周丽杰

    2011-01-01

    Methods of enhancing an aircraft traction system's track following ability and maneuvering stability through automatic tractor steering while the tractor is towing aircraft were discussed. A nonlinear 3 degree of freedom dynamic traction system model,including the steering system,was derived,taking into consideration the articulated angle between tractor and aircraft. Tractor steering angle controllers were designed based on the backstepping variable structure control method,taking into account the aircraft parameters and operating conditions. The boundary layer method was also adopted to modify the control. The simulation results show that the front steering angle controller enables the system to accurately follow the appointed track,and an additional rear steering angle can greatly improve the system stability when the relative angle is too large. The controller can restrict the effect of uncertain parameters,giving the system a robust performance.%探讨了通过牵引车的自动转向来提高牵引车牵引飞机行驶时飞机牵引系统的轨迹跟踪性能和操纵稳定性的基本原理.考虑到牵引车和飞机之间铰接角引起的非线性因素,建立了包含转向系统子模型在内的三自由度飞机牵引系统力学模型.针对飞机参数和运行状态的不确定性,设计基于反演变结构控制方法的牵引车转角控制器,并采用边界层法对控制器进行修正.仿真结果表明,所设计的前轮转角控制器可以使系统精确地跟踪指定轨迹,当相对横摆角过大时,附加的牵引车后轮转角控制器有效地提高了系统稳定性,并且控制器能很好地抑制参数不确定性的影响,使系统具有很好的鲁棒性.

  4. Research on MA700 Aircraft Work Breakdown Structure Method%MA700飞机工作分解结构方法研究

    Institute of Scientific and Technical Information of China (English)

    肖君

    2014-01-01

    This paper introduces the concept of work breakdown structure and its application in the aviation field ,and puts forward the corresponding solutions to problems that MA 700 aircraft is likely to encounter .%介绍了项目工作分解的概念,以及航空领域的应用情况。针对M A700飞机可能遇到的问题,提出相应的解决思路。

  5. Research on Airport's Surrounding Residents'Subjective Annoyance to Aircraft Noise%机场周边居民对飞机噪声反应的主观烦恼度研究

    Institute of Scientific and Technical Information of China (English)

    尹建坤; 田瑞丽; 李洪波; 刘孝峰; 赵仁兴

    2014-01-01

    结合国外对飞机烦恼度的研究,提出了对飞机噪声和烦恼度反应关系的调查方法。通过几个有代表性机场烦恼度调查的人数和声级范围的比较,给出了高烦恼率的计算方法,并分析了高烦恼率和声级相关分析。并给出了数字化等级量表的高烦恼率统计分析方法和文字性描述等级量表的高烦恼率统计分析方法。通过对几个机场烦恼度调查,给出了不同机场周围人群对飞机噪声反应的比较。经过国内外烦恼度调查结果的曲线比较,给出了应该选取的评价量。并通过主观烦恼度阈值的计算得到了高烦恼率统计数值,提出了我国飞机噪声评价标准的建议。%Based on the researches of abroad aircraft annoyance ,this article provides a research method which can find out the relationship between aircraft noise and annoyance .Through comparison of several represent-ative airport annoyance investigation's number of people and sound level range ,high annoyance rate calcula-tion method is found out and correlation analysis .of high annoyance and sound level is done .Digital rating scale and text description rating scale's high annoyance rate statistic analysis method is also provided . Through several airports'annoyance investigation ,the article gives a comparison of different airports sur-rounding residents'reaction to aircraft noise .The comparison of domestic and overseas annoyance investiga-tion results'curves provides the evalation standard that should be selected .The high annoyance statistic is calculated through the subjective annoyance's threshold value ,w hich offers some suggestions to evaluation criteria of aircraft noise .

  6. PREDICTION OF AIRCRAFT NOISE LEVELS

    Science.gov (United States)

    Clark, B. J.

    1994-01-01

    Methods developed at the NASA Lewis Research Center for predicting the noise contributions from various aircraft noise sources have been incorporated into a computer program for predicting aircraft noise levels either in flight or in ground test. The noise sources accounted for include fan inlet and exhaust, jet, flap (for powered lift), core (combustor), turbine, and airframe. Noise propagation corrections are available in the program for atmospheric attenuation, ground reflections, extra ground attenuation, and shielding. The capacity to solve the geometrical relationships between an aircraft in flight and an observer on the ground has been included in the program to make it useful in evaluating noise estimates and footprints for various proposed engine installations. The program contains two main routines for employing the noise prediction routines. The first main routine consists of a procedure to calculate at various observer stations the time history of the noise from an aircraft flying at a specified set of speeds, orientations, and space coordinates. The various components of the noise are computed by the program. For each individual source, the noise levels are free field with no corrections for propagation losses other than spherical divergence. The total spectra may then be corrected for the usual effects of atmospheric attenuation, extra ground attenuation, ground reflection, and aircraft shielding. Next, the corresponding values of overall sound pressure level, perceived noise level, and tone-weighted perceived noise level are calculated. From the time history at each point, true effective perceived noise levels are calculated. Thus, values of effective perceived noise levels, maximum perceived noise levels, and tone-weighted perceived noise levels are found for a grid of specified points on the ground. The second main routine is designed to give the usual format of one-third octave sound pressure level values at a fixed radius for a number of user

  7. [Sildenafil and exercise performance at altitude].

    Science.gov (United States)

    Peidro, Roberto M

    2015-01-01

    Barometric pressure and partial oxygen pressure decrease with increasing altitude. Hypobaric hypoxia produced is responsible for altitude-related diseases and it can cause severe decrements in exercise performance. The physiological adaptations to the altitude are multiple and they contribute to alter different athletic qualities. The VO2 worsening could be associated to increased pulmonary vascular resistance and nitric oxide diffusion alteration. Performance impairments at altitude can also be accentuated by hypoxia-induced elevations in pulmonary arterial pressure. Clinical studies have demonstrated the beneficial effects of sildenafil on the treatment of pulmonary hypertension. These effects have led to suggest that its indication for competitions at altitude might improve athletic performance. The investigations demonstrate different results depending on the altitude level and times and intensities of exercise. Some studies show performance improvements, although not in all participants. Individual responses vary widely between different athletes. This presentation examines the effects of altitude on exercise capacity and shows studies about the use of sildenafil to improve sport performance. This text also discusses the possible side effects and implications for the use of sildenafil in athletes, indication that is not the basic one of the drug. The physicians must know in each athlete the individual sildenafil side effects that could arise and that would influence negatively on health and performance. PMID:26339884

  8. High energy radiation from aircraft-triggered lightning and thunderstorm

    Science.gov (United States)

    Kochkin, Pavlo; van Deursen, Alexander P. J.; de Boer, Alte I.; Bardet, Michiel; Boissin, Jean-François

    2016-04-01

    In-flight Lightning Strike Damage Assessment System (ILDAS http://ildas.nlr.nl/) was developed in an EU FP6 project to provide information on threat that lightning poses to aircraft. The system contains one E-field and eight H-field sensors distributed over the fuselage. It has recently been extended to include two LaBr3 scintillation detectors. The scintillation detectors are sensitive to x-ray photons above 30 keV. The entire system is installed on an A-350 aircraft. When triggered by lightning and digitizes data synchronously with 10 ns intervals. Twelve continuously monitoring photon energy channels were implemented for X-ray detectors operating at slower rate (15 ms, pulse counting). In spring of 2014 and 2015 the aircraft flew through thunderstorm cells recording the data from the sensors. Total of 93 lightning strikes to the aircraft are recorded. Eighteen of them are also detected by WWLLN network. One strike consists of six individual strokes within 200 ms that were all synchronously identified by WWLLN. The WWLLN inter-stroke distance is much larger than the aircraft movement. Three of these strokes generated X-ray bursts. One exceptionally bright X-ray pulse of more than 8 MeV has been detected in association with another strike; it probably saturated the detector's photomultiplier. Neither long gamma-ray glow, nor positron annihilation have been detected during the campaign. An explanation is sought in the typical altitude profile of these test flights.

  9. Cosmic radiation dosimetry onboard aircrafts at the brazilian airspace

    International Nuclear Information System (INIS)

    The objective of this work is the establishment of a dosimetric system for the aircrew in the domestic territory. A technique to perform measurements of ambient dose equivalent in aircrafts was developed. An active detector was evaluated for onboard aircraft use, testing its adequacy to this specific type of measurement as well as its susceptibility to the magnetic and electromagnetic interferences. The equipment was calibrated in standard radiation beams and in a special field of the European Laboratory CERN, that reproduces with great proximity the real spectrum in aircraft flight altitudes; it was also tested in several flights, in an Brazilian Air Force's aircraft. The results were evaluated and compared with those obtained from several computational programs for cosmic radiation estimates, with respect to its adequacy for use in the South American region. The program CARI-6 was selected to evaluate the estimated averaged effective doses for the aircrew who operate in this region. A statistical distribution of aircrew effective doses in South America and Caribe was made, and the results show that a great part of this aircrew members are subjected to annual effective doses that exceed the dose limits for the members of the public. Additionally, a preliminary passive dosemeter, based in thermoluminescent detectors, was proposed; international collaborations with United Kingdom and Italy were established for joint measurements of the ambient equivalent doses in aircrafts. (author)

  10. Research on the Fault of Electronic Cabin Ventilation System in A320 Aircraft%基于对A320飞机电子舱通风系统的故障研究

    Institute of Scientific and Technical Information of China (English)

    崔相国

    2014-01-01

    A320 series aircraft is a type of civil aircraft with single channel and electric control produced by AIRBUS Company, and is the first aircraft which applies electronic control system and side-rod drive technology in the globe. The electronic equipment compartment of the plane contains a large number of control computers as-sociated with flight. During the whole flight, these computers generates huge amount of heat that can seriously im-pact on the safety during flight. This paper thoroughly researches on the operational theory of electronic cabin ven-tilation, and analyzes and summarizes the reasons of electronic cabin ventilation operation failure and thoughts of trouble shooting during maintenance.%A320系列飞机是AIRBUS公司研发的单通道电传操控民用客机,它是世界上第一种采用电传操纵及侧杆驾驶的民用客机。该飞机的电子设备舱存放大量与飞行相关的控制计算机,当飞机在飞行过程中各计算机会产生大量的热量,严重影响航空运行安全。本文深入研究电子舱通风的工作原理,并总结分析航线维护过程中电子舱通风系统故障产生原因与排故思路。

  11. Altitude Training and its Influence on Physical Endurance in Swimmers

    OpenAIRE

    Strzała, Marek; Ostrowski, Andrzej; Szyguła, Zbigniew

    2011-01-01

    It is possible to plan an altitude training (AT) period in such a way that the enhanced physical endurance obtained as a result of adaptation to hypoxia will appear and can be used to improve performance in competition. Yet finding rationales for usage of AT in highly trained swimmers is problematic. In practice AT, in its various forms, is still controversial, and an objective review of research concentrating on the advantages and disadvantages of AT has been presented in several scientific ...

  12. Wilderness medicine at high altitude: recent developments in the field

    OpenAIRE

    Shah NM; Hussain S; Cooke M.; O’Hara JP; Mellor A

    2015-01-01

    Neeraj M Shah,1 Sidra Hussain,2 Mark Cooke,3 John P O’Hara,3 Adrian Mellor3,4 1Division of Asthma, Allergy and Lung Biology, King’s College London, UK; 2School of Medicine, University College London, London, UK; 3Research Institute for Sport, Physical Activity and Leisure, Leeds Beckett University, Leeds, UK; 4Academic Department of Military Anaesthesia and Critical Care, Royal Centre for Defence Medicine, Birmingham, UK Abstract: Travel to high altitude is increasingly p...

  13. Research of Attitude Indicator in Aircraft Cockpit Based on FPGA%基于FPGA的机载全姿态指示仪设计研究

    Institute of Scientific and Technical Information of China (English)

    贾银亮; 张焕春; 经亚枝

    2011-01-01

    机载电子综合显示系统对图形算法的准确性、快速性要求较高,通用的图形处理系统往往不适用;针对机载图形中最耗时的全姿态指示仪,提出一种基于FPGA的硬件生成系统;该系统预测地平线各像素行的像素点数量,使用水平线扫描线进行填充,并在填充的过程中适时的计算轮廓和地平线上坐标;减少了计算量,简化了帧存总线的设计,通过硬件加速提高了图形的生成速度,有效地实现了全姿态指示仪的图形生成.%Aircraft electronic integrative display system needs veracious and fast graphics algorithm and current algorithms usually do not fit it. Attitude indicator in aircraft cockpit spends much time and a new system based on FPGA is presented. The system can get the coordinate of a scanning beam point of the horizon and use level line to fill. The horizon and profile are counted while filling. The graphics of attitude indicator is built with less memory with simply bus and calculation.

  14. Effect of altitude on the protein metabolism of Bolivian children

    International Nuclear Information System (INIS)

    The malnutrition is prevalent and is a major problem among Bolivian children. It is caused by several interacting factors: (1) inadequate protein energy intake due to low socio-economic status; (ii) exposure to acute, repeated and chronic bacterial infections; (iii) exposure to multiple and chronic parasitic infections; (iv) high altitude of the capital, La Paz, 3600 m, with a numerous populations compared to the rest of the country. The research objectives in the first phase are: (i) determination of protein utilization with a non-invasive method using stable isotope tracer among children living at high and low altitude; (ii) determination of protein metabolism among eutrophic children without parasitic or acute bacterial infections at both altitudes; (iii) determination of protein requirement among these children. Two groups of 10 pubertal children, matched for age and sex, of same socio-economic status, eutrophic, without malnutrition, infections or intestinal parasites will be studied; the different status being arrived by anthropometric, nutritional intake, biochemical and pediatrical evaluation. For the metabolic study, stable isotopes L-[1-13C] leucine labelled casein will be used and 13CO2 excreted will be measured. All the basic nutritional assessment and VCO2 measurements will be performed in Bolivia, while the samples of expired gas will be stored in Vacutainers for further analysis by isotope radio mass spectrometer (IRMS), in Clermont-Ferrand, France. The plans for future work is based on the study of the effects of the different variables and their interactions. The following will be evaluated: (i) the socio-economic status; (ii) the bacterial infections: (iii) the parasitic infections; (iv) the altitude. As published by Obert, et al., the socio-economic variable is more connected with the nutritional status than with the altitude. 12 refs, 1 fig., 1 tab

  15. IDENTIFICATION OF AIRCRAFT HAZARDS

    International Nuclear Information System (INIS)

    Aircraft hazards were determined to be potentially applicable to a repository at Yucca Mountain in the ''Monitored Geological Repository External Events Hazards Screening Analysis'' (BSC 2004, Section 6.4.1). That determination was conservatively based on limited knowledge of flight data in the area of concern and on crash data for aircraft of the type flying near Yucca Mountain. The purpose of this report is to identify specific aircraft hazards that may be applicable to a Monitored Geologic Repository (MGR) at Yucca Mountain using NUREG-0800, ''Standard Review Plan for the Review of Safety Analysis Reports for Nuclear Power Plants'' (NRC 1987, Section 3.5.1.6), as guidance for the inclusion or exclusion of identified aircraft hazards. NUREG-0800 is being used here as a reference because some of the same considerations apply. The intended use of this report is to provide inputs for further screening and analysis of the identified aircraft hazards based on the criteria that apply to Category 1 and 2 event sequence analyses as defined in 10 CFR 63.2 (see Section 4). The scope of this technical report includes the evaluation of military, private, and commercial use of airspace in the 100-mile regional setting of the MGR at Yucca Mountain with the potential for reducing the regional setting to a more manageable size after consideration of applicable screening criteria (see Section 7)

  16. Aircraft Operations Classification System

    Science.gov (United States)

    Harlow, Charles; Zhu, Weihong

    2001-01-01

    Accurate data is important in the aviation planning process. In this project we consider systems for measuring aircraft activity at airports. This would include determining the type of aircraft such as jet, helicopter, single engine, and multiengine propeller. Some of the issues involved in deploying technologies for monitoring aircraft operations are cost, reliability, and accuracy. In addition, the system must be field portable and acceptable at airports. A comparison of technologies was conducted and it was decided that an aircraft monitoring system should be based upon acoustic technology. A multimedia relational database was established for the study. The information contained in the database consists of airport information, runway information, acoustic records, photographic records, a description of the event (takeoff, landing), aircraft type, and environmental information. We extracted features from the time signal and the frequency content of the signal. A multi-layer feed-forward neural network was chosen as the classifier. Training and testing results were obtained. We were able to obtain classification results of over 90 percent for training and testing for takeoff events.

  17. Identification of Aircraft Hazards

    International Nuclear Information System (INIS)

    Aircraft hazards were determined to be potentially applicable to a repository at Yucca Mountain in ''Monitored Geological Repository External Events Hazards Screening Analysis'' (BSC 2005 [DIRS 174235], Section 6.4.1). That determination was conservatively based upon limited knowledge of flight data in the area of concern and upon crash data for aircraft of the type flying near Yucca Mountain. The purpose of this report is to identify specific aircraft hazards that may be applicable to a monitored geologic repository (MGR) at Yucca Mountain, using NUREG-0800, ''Standard Review Plan for the Review of Safety Analysis Reports for Nuclear Power Plants'' (NRC 1987 [DIRS 103124], Section 3.5.1.6), as guidance for the inclusion or exclusion of identified aircraft hazards. The intended use of this report is to provide inputs for further screening and analysis of identified aircraft hazards based upon the criteria that apply to Category 1 and Category 2 event sequence analyses as defined in 10 CFR 63.2 [DIRS 176544] (Section 4). The scope of this report includes the evaluation of military, private, and commercial use of airspace in the 100-mile regional setting of the repository at Yucca Mountain with the potential for reducing the regional setting to a more manageable size after consideration of applicable screening criteria (Section 7)

  18. IDENTIFICATION OF AIRCRAFT HAZARDS

    Energy Technology Data Exchange (ETDEWEB)

    K.L. Ashley

    2005-03-23

    Aircraft hazards were determined to be potentially applicable to a repository at Yucca Mountain in the ''Monitored Geological Repository External Events Hazards Screening Analysis'' (BSC 2004, Section 6.4.1). That determination was conservatively based on limited knowledge of flight data in the area of concern and on crash data for aircraft of the type flying near Yucca Mountain. The purpose of this report is to identify specific aircraft hazards that may be applicable to a Monitored Geologic Repository (MGR) at Yucca Mountain using NUREG-0800, ''Standard Review Plan for the Review of Safety Analysis Reports for Nuclear Power Plants'' (NRC 1987, Section 3.5.1.6), as guidance for the inclusion or exclusion of identified aircraft hazards. NUREG-0800 is being used here as a reference because some of the same considerations apply. The intended use of this report is to provide inputs for further screening and analysis of the identified aircraft hazards based on the criteria that apply to Category 1 and 2 event sequence analyses as defined in 10 CFR 63.2 (see Section 4). The scope of this technical report includes the evaluation of military, private, and commercial use of airspace in the 100-mile regional setting of the MGR at Yucca Mountain with the potential for reducing the regional setting to a more manageable size after consideration of applicable screening criteria (see Section 7).

  19. Identification of Aircraft Hazards

    Energy Technology Data Exchange (ETDEWEB)

    K. Ashley

    2006-12-08

    Aircraft hazards were determined to be potentially applicable to a repository at Yucca Mountain in ''Monitored Geological Repository External Events Hazards Screening Analysis'' (BSC 2005 [DIRS 174235], Section 6.4.1). That determination was conservatively based upon limited knowledge of flight data in the area of concern and upon crash data for aircraft of the type flying near Yucca Mountain. The purpose of this report is to identify specific aircraft hazards that may be applicable to a monitored geologic repository (MGR) at Yucca Mountain, using NUREG-0800, ''Standard Review Plan for the Review of Safety Analysis Reports for Nuclear Power Plants'' (NRC 1987 [DIRS 103124], Section 3.5.1.6), as guidance for the inclusion or exclusion of identified aircraft hazards. The intended use of this report is to provide inputs for further screening and analysis of identified aircraft hazards based upon the criteria that apply to Category 1 and Category 2 event sequence analyses as defined in 10 CFR 63.2 [DIRS 176544] (Section 4). The scope of this report includes the evaluation of military, private, and commercial use of airspace in the 100-mile regional setting of the repository at Yucca Mountain with the potential for reducing the regional setting to a more manageable size after consideration of applicable screening criteria (Section 7).

  20. Rich diversity and potency of skin antioxidant peptides revealed a novel molecular basis for high-altitude adaptation of amphibians

    OpenAIRE

    Xinwang Yang; Ying Wang; Yue Zhang; Wen-Hui Lee; Yun Zhang

    2016-01-01

    Elucidating the mechanisms of high-altitude adaptation is an important research area in modern biology. To date, however, knowledge has been limited to the genetic mechanisms of adaptation to the lower oxygen and temperature levels prevalent at high altitudes, with adaptation to UV radiation largely neglected. Furthermore, few proteomic or peptidomic analyses of these factors have been performed. In this study, the molecular adaptation of high-altitude Odorrana andersonii and cavernicolous O....

  1. Propulsion Selection for 85kft Remotely Piloted Atmospheric Science Aircraft

    Science.gov (United States)

    Bents, David J.; Mockler, Ted; Maldonado, Jaime; Hahn, Andrew; Cyrus, John; Schmitz, Paul; Harp, Jim; King, Joseph

    1996-01-01

    This paper describes how a 3 stage turbocharged gasoline engine was selected to power NASA's atmospheric science unmanned aircraft now under development. The airplane, whose purpose is to fly sampling instruments through targeted regions of the upper atmosphere at the exact location and time (season, time of day) where the most interesting chemistry is taking place, must have a round trip range exceeding 1000 km, carry a payload of about 500 lb to altitudes exceeding 80 kft over the site, and be able to remain above that altitude for at least 30 minutes before returning to base. This is a subsonic aircraft (the aerodynamic heating and shock associated with supersonic flight could easily destroy the chemical species that are being sampled) and it must be constructed so it will operate out of small airfields at primitive remote sites worldwide, under varying climate and weather conditions. Finally it must be low cost, since less than $50 M is available for its development. These requirements put severe constraints on the aircraft design (for example, wing loading in the vicinity of 10 psf) and have in turn limited the propulsion choices to already-existing hardware, or limited adaptations of existing hardware. The only candidate that could emerge under these circumstances was a propeller driven aircraft powered by spark ignited (SI) gasoline engines, whose intake pressurization is accomplished by multiple stages of turbo-charging and intercooling. Fortunately the turbocharged SI powerplant, owing to its rich automotive heritage and earlier intensive aero powerplant development during WWII, enjoys in addition to its potentially low development costs some subtle physical advantages (arising from its near-stochiometric combustion) that may make it smaller and lighter than either a turbine engine or a diesel for these altitudes. Just as fortunately, the NASA/industry team developing this aircraft includes the same people who built multi-stage turbocharged SI powerplants

  2. Incident response monitoring technologies for aircraft cabin

    NARCIS (Netherlands)

    Havermans, J.B.G.A.; Houtzager, M.M.G.; Jacobs, P.

    2015-01-01

    The Netherlands Organization for Applied Scientific Research (TNO) was granted by ASHRAE (1306-RP) to conduct scientfic review and feasibility analysis of technologies and methods for measuring aircraft power system contaminants in the cabin air during unanticipated adverse incidents. In particular,

  3. Design and Testing of a Flight Control System for Unstable Subscale Aircraft

    OpenAIRE

    Sobron, Alejandro

    2015-01-01

    The primary objective of this thesis was to study, implement, and test low-cost electronic flight control systems (FCS) in remotely piloted subscale research aircraft with relaxed static longitudinal stability. Even though this implementation was carried out in small, simplified test-bed aircraft, it was designed with the aim of being installed later in more complex demonstrator aircraft such as the Generic Future Fighter concept demonstrator project. The recent boom of the unmanned aircraft ...

  4. A strategic planning methodology for aircraft redesign

    Science.gov (United States)

    Romli, Fairuz Izzuddin

    Due to a progressive market shift to a customer-driven environment, the influence of engineering changes on the product's market success is becoming more prominent. This situation affects many long lead-time product industries including aircraft manufacturing. Derivative development has been the key strategy for many aircraft manufacturers to survive the competitive market and this trend is expected to continue in the future. Within this environment of design adaptation and variation, the main market advantages are often gained by the fastest aircraft manufacturers to develop and produce their range of market offerings without any costly mistakes. This realization creates an emphasis on the efficiency of the redesign process, particularly on the handling of engineering changes. However, most activities involved in the redesign process are supported either inefficiently or not at all by the current design methods and tools, primarily because they have been mostly developed to improve original product development. In view of this, the main goal of this research is to propose an aircraft redesign methodology that will act as a decision-making aid for aircraft designers in the change implementation planning of derivative developments. The proposed method, known as Strategic Planning of Engineering Changes (SPEC), combines the key elements of the product redesign planning and change management processes. Its application is aimed at reducing the redesign risks of derivative aircraft development, improving the detection of possible change effects propagation, increasing the efficiency of the change implementation planning and also reducing the costs and the time delays due to the redesign process. To address these challenges, four research areas have been identified: baseline assessment, change propagation prediction, change impact analysis and change implementation planning. Based on the established requirements for the redesign planning process, several methods and

  5. Titanium alloys Russian aircraft and aerospace applications

    CERN Document Server

    Moiseyev, Valentin N

    2005-01-01

    This text offers previously elusive information on state-of-the-art Russian metallurgic technology of titanium alloys. It details their physical, mechanical, and technological properties, as well as treatments and applications in various branches of modern industry, particularly aircraft and aerospace construction. Titanium Alloys: Russian Aircraft and Aerospace Applications addresses all facets of titanium alloys in aerospace and aviation technology, including specific applications, fundamentals, composition, and properties of commercial alloys. It is useful for all students and researchers interested in the investigation and applications of titanium.

  6. Research for damage of the cardiovascular system when exposed in high altitude hypoxia environment%高原低氧环境对心血管系统影响的研究

    Institute of Scientific and Technical Information of China (English)

    白谊涵; 马全福; 张永青; 李燕宁; 林红兰; 袁延年; 常开齐

    2012-01-01

    目的 评价高原低氧环境对心血管系统的影响.方法 人群试验采用分组调查从平原到高原地区工作的男性青年志愿者1 244人.其中A组486人,地区海拔2 260~2 800 m;B组675人,海拔3800~4 300 m;C组83人,海拔>4 500 m.对比分析各组症状反应及入住时间和海拔高度的关系.动物实验:将平原兔24只随机分为4组,每组6只.A组为平原对照组,B、C、D组为平原兔在48 h内直接迁饲到海拔4 320m地区后1 d、7 d和30 d组.选高原(海拔2 260 m)兔12只随机分为E、F两组,每组6只,E组为高原对照组,F组为24 h内迁饲到海拔4 320 m后1 d.各组宰杀后取心脏及动静脉行HE染色进行病理学观察.结果 人群试验结果:B组和C组人群平均血氧饱和度值分别为88.14%和74.50%,明显低于A组.A、B、C组胸闷、气短、心悸和口唇紫绀症状阳性率组间比较差异有统计学意义(P0.05).动物实验结果:与A组相比,B组心肌间隙增宽,内充红细胞,部分心肌浑浊肿胀,横纹消失或凝固性变,核大小不一致,间质内血管扩张充血;C、D组病变与B组相比较轻.E、F组心肌排列正常,部分心肌横纹模糊或消失,心肌毛细血管扩张充血,核大小一致.在D、E、F组可见动脉血管内皮细胞增生,静脉管壁增厚.结论 心血管系统的低氧应激性症状反应与海拔高度成正比,尤其海拔3 800 m以上地区的症状反应阳性率陡然升高,但随入住时间的延长而下降.高原低氧环境可使心肌细胞形态学发生改变,与海拔及居住时间有关.%Objective To explore the effect on the cardiovascular system when exposed actively in high altitude hypoxia environment. Methods In human trial, 1,244 young male volunteers who work in the high altitude environment transferred from plain were randomly divided into three groups, group A of 486 people on 2,260-2,800 meters above sea levels, group B of 675 people on 3,800-4,300 meters and group C of 83 people on and

  7. Video Altimeter and Obstruction Detector for an Aircraft

    Science.gov (United States)

    Delgado, Frank J.; Abernathy, Michael F.; White, Janis; Dolson, William R.

    2013-01-01

    Video-based altimetric and obstruction detection systems for aircraft have been partially developed. The hardware of a system of this type includes a downward-looking video camera, a video digitizer, a Global Positioning System receiver or other means of measuring the aircraft velocity relative to the ground, a gyroscope based or other attitude-determination subsystem, and a computer running altimetric and/or obstruction-detection software. From the digitized video data, the altimetric software computes the pixel velocity in an appropriate part of the video image and the corresponding angular relative motion of the ground within the field of view of the camera. Then by use of trigonometric relationships among the aircraft velocity, the attitude of the camera, the angular relative motion, and the altitude, the software computes the altitude. The obstruction-detection software performs somewhat similar calculations as part of a larger task in which it uses the pixel velocity data from the entire video image to compute a depth map, which can be correlated with a terrain map, showing locations of potential obstructions. The depth map can be used as real-time hazard display and/or to update an obstruction database.

  8. 飞机氮氧化物排放指数计算方法研究%Research on the Calculation of Aircraft NOx Emission Index

    Institute of Scientific and Technical Information of China (English)

    张青; 安梓琪; 闫国华; 周利敏

    2015-01-01

    飞机发动机的噪声和氮氧化物排放已成为日益严重的环境问题,对人类和生态环境的影响越来越严重。自国际民航组织颁布国际民航公约附件16《第Ⅰ卷航空器噪声》和《第Ⅱ卷航空发动机排放物》以来,为控制航空器发动机排放物污染,特别是氮氧化物污染,国际民航组织一直在研究更加严格的发动机排放物限制标准,以减少航空活动中飞机发动机对人类和环境的影响。以实例的形式列举了B787-800在4个阶段氮氧化物排放指数(EINOx )的计算过程,可为我国大飞机氮氧化物排放适航标准提供信息参考。%Nowadays aircraft noise and engine NO x emission has become an increa-singly seious environmental problem and it may be harmful to human beings and eclolgy .Since the issue of Annex16“Aircaft Noise Volume I”and“Aircraft Engine E-missions VolumeⅡ”by International Civi 1 Aviation Organization ,to control pollution of noises and emissions ,especially NOx e-missions ,ICAO has been working on the stricter engine emissions standards ,which can reduce the impact of aviation activities on human beings and ecology .Taking B787-800 as example ,the calculation of NOx emission index at four stages is conducted in this paper ,which may provide references for NOx emission standard airworthiness of Chinese aircraft fleet .

  9. Safety research on unmanned aircraft system for airworthiness%无人机系统适航与安全性分析方法

    Institute of Scientific and Technical Information of China (English)

    丁水汀; 鲍梦瑶; 杜发荣

    2012-01-01

    Aiming at safety requirement for unmanned aircraft system (UAS), it was initially demonstrated that current safety assessment process and methodology based on reg- ulation and reference for manned aircraft were limited for UAS because of its unique fea- tures. In views of this principle, some improvements for UAS safety assessment were pro- posed: (1) take consideration of UAS including the unmanned aerial vehicle and assured e- quipments, and enlarge the scope of safety assessment during functional hazard analysis at system level; (2) take consideration of the feature that pilot and unmanned aircraft are physically separated, and reclassify and redefine the serious level of UAS failures. (3) con- sider that the quality of take-off has a huge impact on system, and the safety analysis must be conducted for two key events- ~air collision' and 'ground impact'. The result indicates that the above improvements are in accordance with features of UAV and ensures safety through establishing targeted safety level.%针对无人机系统安全性需求,首先根据载人航空器适航审定规范及安全性评估依据,表明由于无人机系统的特殊性造成直接应用现有安全性评估流程和评估方法具有局限性.在此基础上提出无人机系统适航安全性评估的几点改进:①考虑无人机系统包括无人机和综合保障设备,扩大安全性评估边界进行无人机系统级的功能危险分析;②考虑无人机系统"人机分离"特点,需要对无人机系统失效状态的严重程度进行重新分级和定义;③考虑无人机系统本身受起飞质量的影响很大,强调必须根据无人机系统分类对地面撞击和空中碰撞两个关键事件进行安全性分析.结果表明:上述改进从无人机系统本身特点出发,通过给定的目标安全水平进一步确保安全性.

  10. Research on Mass Data Processing Oriented to Aircraft Manufacturing Industry%面向航空制造业的海量数据处理研究

    Institute of Scientific and Technical Information of China (English)

    吴恒; 王东勃

    2013-01-01

    为了向航空制造业的海量数据处理提供一种新颖的模式,以Hadoop开源软件平台为架构,介绍了HDFS分布式存储系统和Map-Reduce编程模式,分析了航空制造业海量数据处理需求,提出了一种应用于航空制造业的海量数据处理模型,即将数据格式划分为若干个主要字段,按照该数据格式在分片中对数据进行深度优先挖掘,将提取出的数据以键值对的形式并按照一定的存储格式存储于HDFS中,利用Map-Reduce并行算法对存储的数据进行排序和分区处理.最后提出了基于K-NN的并行化数据挖掘算法,且分析了海量数据处理模型的扩展性、实时性和快速处理等性能.%In order to provide a new model of mass data processing for aircraft manufacturing industry,it proposes a model of mass data processing for aircraft manufacturing industry based on Hadoop software platform,introduces the HDFS and the Map-Reduce programming model,analyzes the demand of mass data processing for aircraft manufacturing industry,introduces a kind of data processing model.This system can divide the data format into several major fields,mine the data from sharding deeply and firstly according to the data format,store the extracted data in HDFS in the format of key-value and the defined storage format,sort and partition the storage data in the method of Map-Reduce.Lastly,it illustrates a parallel data mining algorithm based K-NN,and analyzes the expansibility,instantaneity and quick processing of this kind of mass data processing model.

  11. Global distribution of halogenated tracers in the UTLS region during the TACTS/ESMVal campaigns using the HALO aircraft

    Science.gov (United States)

    Keber, Timo; Engel, Andreas; Boenisch, Harald; Sala, Stephan

    2013-04-01

    The Upper Troposphere / Lower Stratosphere (UTLS) represents an important region for the exchange of air between the stratosphere and the troposphere. Tropospheric gaseous compounds such as greenhouse gases and ozone depleting substances (ODS) are transported into the lower stratosphere on different pathways. Especially the two-way horizontal transport across the subtropical jet was further investigated during the "TACTS - Transport and Composition in the UT/LMS" campaign. We will present in-situ measurements of long-lived and very short-lived (VSLS) halocarbons and Sulfurhexafluoride (SF6) in the UTLS region. The measurements were performed with a sophisticated two channel in-situ instrument on board of the new German research aircraft for atmospheric science HALO (The High Altitude and LOng Range Research Aircraft) during the two campaigns TACTS and "ESMVal - Earth System Modell Validation". The first channel is a gas chromatography (GC) system coupled with mass spectrometer (MS) which operates in negative chemical ionization mode. This GC/MS channel is able to measure halocarbons in ambient air with a time resolution of four minutes. For the measurement of SF6 and CFC-12 the second channel provides its own GC system with an electron capture detector (ECD). With the GC/ECD we achieve a time resolution of 60 seconds. The dataset includes 13 flights with a total of 120 flight hours and a coverage from 80° N to 65° S with a maximum altitude of 15 km. The measurements include halogenated hydrocarbons with a wide span of chemical lifetimes reaching from 100 years for CFC-12 to 26 days for CHBr3. On the basis of this distribution we can improve our understanding of transport timescales, compositions and pathways in the UTLS region. Furthermore we discuss the distribution in respect of atmospheric transport and lifetimes.

  12. Control strategies for aircraft airframe noise reduction

    Institute of Scientific and Technical Information of China (English)

    Li Yong; Wang Xunnian; Zhang Dejiu

    2013-01-01

    With the development of low-noise aircraft engine,airframe noise now represents a major noise source during the commercial aircraft's approach to landing phase.Noise control efforts have therefore been extensively focused on the airframe noise problems in order to further reduce aircraft overall noise.In this review,various control methods explored in the last decades for noise reduction on airframe components including high-lift devices and landing gears are summarized.We introduce recent major achievements in airframe noise reduction with passive control methods such as fairings,deceleration plates,splitter plates,acoustic liners,slat cove cover and side-edge replacements,and then discuss the potential and control mechanism of some promising active flow control strategies for airframe noise reduction,such as plasma technique and air blowing/suction devices.Based on the knowledge gained throughout the extensively noise control testing,a few design concepts on the landing gear,high-lift devices and whole aircraft are provided for advanced aircraft low-noise design.Finally,discussions and suggestions are given for future research on airframe noise reduction.

  13. High Altitude Clear Air Turbulence Project

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The Air Force Flight Dynamics Laboratory conducted the High Altitude Clear Air Turbulence Project in the mid 1960s with the intention of better understanding air...

  14. Case Study: Test Results of a Tool and Method for In-Flight, Adaptive Control System Verification on a NASA F-15 Flight Research Aircraft

    Science.gov (United States)

    Jacklin, Stephen A.; Schumann, Johann; Guenther, Kurt; Bosworth, John

    2006-01-01

    Adaptive control technologies that incorporate learning algorithms have been proposed to enable autonomous flight control and to maintain vehicle performance in the face of unknown, changing, or poorly defined operating environments [1-2]. At the present time, however, it is unknown how adaptive algorithms can be routinely verified, validated, and certified for use in safety-critical applications. Rigorous methods for adaptive software verification end validation must be developed to ensure that. the control software functions as required and is highly safe and reliable. A large gap appears to exist between the point at which control system designers feel the verification process is complete, and when FAA certification officials agree it is complete. Certification of adaptive flight control software verification is complicated by the use of learning algorithms (e.g., neural networks) and degrees of system non-determinism. Of course, analytical efforts must be made in the verification process to place guarantees on learning algorithm stability, rate of convergence, and convergence accuracy. However, to satisfy FAA certification requirements, it must be demonstrated that the adaptive flight control system is also able to fail and still allow the aircraft to be flown safely or to land, while at the same time providing a means of crew notification of the (impending) failure. It was for this purpose that the NASA Ames Confidence Tool was developed [3]. This paper presents the Confidence Tool as a means of providing in-flight software assurance monitoring of an adaptive flight control system. The paper will present the data obtained from flight testing the tool on a specially modified F-15 aircraft designed to simulate loss of flight control faces.

  15. Research on Fatigue Curves for Pre-corroded Aircraft Structures%飞机结构预腐蚀疲劳曲线研究

    Institute of Scientific and Technical Information of China (English)

    王忠波; 刘文珽; 贺小帆

    2004-01-01

    为评估地面停放预腐蚀对飞机结构疲劳寿命的影响,采用二元线性回归方法建立了一种新的预腐蚀疲劳曲线幂函数表达式.该曲线的指数为常量而对数截距是预腐蚀时间的线性函数.这两个特性使得曲线形式简单,参数几何、工程含义明确,并易于工程应用.通过寿命反推建立了参数修正的三参数预腐蚀疲劳曲线,该曲线已成功用于飞机结构腐蚀条件下的疲劳寿命估算.%To quantitatively evaluate the effects of corrosion during grounding on fatigue life of aircraft structures, a new power equation is proposed using two-variable linear regression method. That the slope is a constant and the logarithmic intercept is a linear function of pre-corrosion time makes this equation advantageous: it has a simple form, its parameters have unambiguous technical and geometrical meanings, and it facilitates engineering applications. Three-parameter equations after pre-corrosion are obtained from back-calculation of fatigue limits, which have been successfully used to predict safe life of aircraft structures in corrosive environment.

  16. Child health and living at high altitude.

    Science.gov (United States)

    Niermeyer, S; Andrade Mollinedo, P; Huicho, L

    2009-10-01

    The health of children born and living at high altitude is shaped not only by the low-oxygen environment, but also by population ancestry and sociocultural determinants. High altitude and the corresponding reduction in oxygen delivery during pregnancy result in lower birth weight with higher elevation. Children living at high elevations are at special risk for hypoxaemia during infancy and during acute lower respiratory infection, symptomatic high-altitude pulmonary hypertension, persistence of fetal vascular connections, and re-entry high-altitude pulmonary oedema. However, child health varies from one population group to another due to genetic adaptation as well as factors such as nutrition, intercurrent infection, exposure to pollutants and toxins, socioeconomic status, and access to medical care. Awareness of the risks uniquely associated with living at high altitude and monitoring of key health indicators can help protect the health of children at high altitude. These considerations should be incorporated into the scaling-up of effective interventions for improving global child health and survival. PMID:19066173

  17. Measurement of the energy spectrum of cosmic-ray induced neutrons aboard an ER-2 high-altitude airplane.

    Science.gov (United States)

    Goldhagen, P; Reginatto, M; Kniss, T; Wilson, J W; Singleterry, R C; Jones, I W; Van Steveninck, W

    2002-01-01

    Crews working on present-day jet aircraft are a large occupationally exposed group with a relatively high average effective dose from galactic cosmic radiation. Crews of future high-speed commercial aircraft flying at higher altitudes would be even more exposed. To help reduce the significant uncertainties in calculations of such exposures, the atmospheric ionizing radiation (AIR) project, an international collaboration of 15 laboratories, made simultaneous radiation measurements with 14 instruments on five flights of a NASA ER-2 high-altitude aircraft. The primary AIR instrument was a highly sensitive extended-energy multisphere neutron spectrometer with lead and steel shells placed within the moderators of two of its 14 detectors to enhance response at high energies. Detector responses were calculated for neutrons and charged hadrons at energies up to 100 GeV using MCNPX. Neutron spectra were unfolded from the measured count rates using the new MAXED code. We have measured the cosmic-ray neutron spectrum (thermal to >10 GeV), total neutron fluence rate, and neutron effective dose and dose equivalent rates and their dependence on altitude and geomagnetic cutoff. The measured cosmic-ray neutron spectra have almost no thermal neutrons, a large "evaporation" peak near 1 MeV and a second broad peak near 100 MeV which contributes about 69% of the neutron effective dose. At high altitude, geomagnetic latitude has very little effect on the shape of the spectrum, but it is the dominant variable affecting neutron fluence rate, which was eight times higher at the northernmost measurement location than it was at the southernmost. The shape of the spectrum varied only slightly with altitude from 21 km down to 12 km (56-201 g cm-2 atmospheric depth), but was significantly different on the ground. In all cases, ambient dose equivalent was greater than effective dose for cosmic-ray neutrons.

  18. Auralization of novel aircraft configurations

    OpenAIRE

    Arntzen, M.; Bertsch, E.L.; Simons, D.G.

    2015-01-01

    A joint initiative of NLR, DLR, and TU Delft has been initiated to streamline the process of generating audible impressions of novel aircraft configurations. The integrated approach adds to the value of the individual tools and allows predicting the sound of future aircraft before they actually fly. Hence, an existing process for the aircraft design and system noise prediction at DLR has been upgraded to generate the required input data for an aircraft auralization framework developed by NLR ...

  19. Long Range Aircraft Trajectory Prediction

    OpenAIRE

    Magister, Tone

    2009-01-01

    The subject of the paper is the improvement of the aircraft future trajectory prediction accuracy for long-range airborne separation assurance. The strategic planning of safe aircraft flights and effective conflict avoidance tactics demand timely and accurate conflict detection based upon future four–dimensional airborne traffic situation prediction which is as accurate as each aircraft flight trajectory prediction. The improved kinematics model of aircraft relative flight considering flight ...

  20. X-Band Radar for Studies of Tropical Storms from High Altitude UAV Platform

    Science.gov (United States)

    Rodriquez, Shannon; Heymsfield, Gerald; Li, Lihua; Bradley, Damon

    2007-01-01

    The increased role of unmanned aerial vehicles (UAV) in NASA's suborbital program has created a strong interest in the development of instruments with new capabilities, more compact sizes and reduced weights than the instruments currently operated on manned aircrafts. There is a strong demand and tremendous potential for using high altitude UAV (HUAV) to carry weather radars for measurements of reflectivity and wind fields from tropical storms. Tropical storm genesis frequently occurs in ocean regions that are inaccessible to piloted aircraft due to the long off shore range and the required periods of time to gather significant data. Important factors of interest for the study of hurricane genesis include surface winds, profiled winds, sea surface temperatures, precipitation, and boundary layer conditions. Current satellite precipitation and surface wind sensors have resolutions that are too large and revisit times that are too infrequent to study this problem. Furthermore, none of the spaceborne sensors measure winds within the storm itself. A dual beam X-band Doppler radar, UAV Radar (URAD), is under development at the NASA Goddard Space Flight Center for the study of tropical storms from HUAV platforms, such as a Global Hawk. X-band is the most desirable frequency for airborne weather radars since these can be built in a relatively compact size using off-the-shelf components which cost significantly less than other higher frequency radars. Furthermore, X-band radars provide good sensitivity with tolerable attenuation in storms. The low-cost and light-weight URAD will provide new capabilities for studying hurricane genesis by analyzing the vertical structure of tropical cyclones as well as 3D reflectivity and wind fields in clouds. It will enable us to measure both the 3D precipitation structure and surface winds by using two antenna beams: fixed nadir and conical scanning each produced by its associated subsystem. The nadir subsystem is a magnetron based radar

  1. Physiological aspects of altitude training and the use of altitude simulators

    Directory of Open Access Journals (Sweden)

    Ranković Goran

    2005-01-01

    Full Text Available Altitude training in various forms is widely practiced by athletes and coaches in an attempt to improve sea level endurance. Training at high altitude may improve performance at sea level through altitude acclimatization, which improves oxygen transport and/or utilization, or through hypoxia, which intensifies the training stimulus. This basic physiological aspect allows three training modalities: live high and train high (classic high-altitude training, live low and train high (training through hypoxia, and live high and train low (the new trend. In an effort to reduce the financial and logistical challenges of traveling to high-altitude training sites, scientists and manufactures have developed artificial high-altitude environments, which simulate the hypoxic conditions of moderate altitude (2000-3000 meters. Endurance athletes from many sports have recently started using nitrogen environments, or hypoxic rooms and tents as part of their altitude training programmes. The results of controlled studies on these modalities of high-altitude training, their practical approach, and ethics are summarized.

  2. Persistent organic pollutants (POPs) as environmental risk factors in remote high-altitude ecosystems.

    Science.gov (United States)

    Kallenborn, Roland

    2006-01-01

    Persistent organic pollutants (POPs), and their transformation products, are the most investigated organic environmental contaminants within the past five decades. Organochlorines have been found in virtually all environmental compartments on the globe. Severe environmental implications have been shown to be associated with the presence of the POP group of contaminants in the environment. However, in the late 1990s, Canadian scientists first pinpointed the implication of POPs for high-altitude environments in a comprehensive way (Blais et al., 1998, Nature 395, 585-588). Under certain meteorological and geographic conditions, high-altitude environments can serve as "cold condensers" for atmospheric POP loadings. Subsequent investigations in high-altitude environments in Asia, Europe, and North and South America have confirmed suspicions that high-altitude mountainous regions have the potential to serve as focus regions for POPs and even for nonpersistent, medium-lived contaminants, such as "currently used pesticides", due to cold condensation and deposition in high altitudes. Although the presence and the altitude-dependent increase of POP levels in mountainous regions are confirmed by many international studies, the ecotoxicological consequences still remain largely unknown. At present, only a few studies have been published describing the biological effects in high-altitude environments due to increased POP exposure. Therefore, in this early stage of the international research effort on the ecotoxicological risk evaluation of persistent contaminants in high-altitude, pristine ecosystems, the present review intends to summarize the current state of research on POPs in high-altitude environments and draw preliminary conclusions on possible consequences of the presence of POPs in mountainous ecosystems based on currently available information from alpine and related Arctic environments. PMID:16399161

  3. Vibration and aeroelastic analysis of highly flexible HALE aircraft

    Science.gov (United States)

    Chang, Chong-Seok

    The highly flexible HALE (High Altitude Long Endurance) aircraft analysis methodology is of interest because early studies indicated that HALE aircraft might have different vibration and aeroelastic characteristics from those of conventional aircraft. Recently the computer code Nonlinear Aeroelastic Trim And Stability of HALE Aircraft (NATASHA) was developed under NASA sponsorship. NATASHA can predict the flight dynamics and aeroelastic behavior for HALE aircraft with a flying wing configuration. Further analysis improvements for NATASHA were required to extend its capability to the ground vibration test (GVT) environment and to both GVT and aeroelastic behavior of HALE aircraft with other configurations. First, the analysis methodology, based on geometrically exact fully intrinsic beam theory, was extended to treat other aircraft cofigurations. Conventional aircraft with flexible fuselage and tail can now be modeled by treating the aircraft as an assembly of beam elements. NATASHA is now applicable to any aircraft cofiguration that can be modeled this way. The intrinsic beam formulation, which is a fundamental structural modeling approach, is now capable of being applying to a structure consisting of multiple beams by relating the virtual displacements and rotations at points where two or more beam elements are connected to each other. Additional aspects are also considered in the analysis such as auxiliary elevator input in the horizontal tail and fuselage aerodynamics. Second, the modeling approach was extended to treat the GVT environment for HALE aircraft, which have highly flexible wings. GVT has its main purpose to provide modal characteristics for model validation. A bungee formulation was developed by the augmented Lagrangian method and coupled to the intrinsic beam formulation for the GVT modeling. After the coupling procedure, the whole formulation cannot be fully intrinsic because the geometric constraint by bungee cords makes the system statically

  4. Robots for Aircraft Maintenance

    Science.gov (United States)

    1993-01-01

    Marshall Space Flight Center charged USBI (now Pratt & Whitney) with the task of developing an advanced stripping system based on hydroblasting to strip paint and thermal protection material from Space Shuttle solid rocket boosters. A robot, mounted on a transportable platform, controls the waterjet angle, water pressure and flow rate. This technology, now known as ARMS, has found commercial applications in the removal of coatings from jet engine components. The system is significantly faster than manual procedures and uses only minimal labor. Because the amount of "substrate" lost is minimal, the life of the component is extended. The need for toxic chemicals is reduced, as is waste disposal and human protection equipment. Users of the ARMS work cell include Delta Air Lines and the Air Force, which later contracted with USBI for development of a Large Aircraft Paint Stripping system (LARPS). LARPS' advantages are similar to ARMS, and it has enormous potential in military and civil aircraft maintenance. The technology may also be adapted to aircraft painting, aircraft inspection techniques and paint stripping of large objects like ships and railcars.

  5. Hybrid Prediction Method for Aircraft Interior Noise Project

    Data.gov (United States)

    National Aeronautics and Space Administration — The goal of the project is research and development of methods for application of the Hybrid FE-SEA method to aircraft vibro-acoustic problems. This proposal...

  6. Implementation of Extreme STOL Capability in Cruise Efficient Aircraft Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Aerotonomy, Incorporated and the Georgia Tech Research Institute (GTRI), will develop enabling technologies for an aircraft that is capable of Extreme Short Takeoff...

  7. Advanced Acoustic Blankets for Improved Aircraft Interior Noise Reduction Project

    Data.gov (United States)

    National Aeronautics and Space Administration — The objective of the proposed Phase II research effort is to develop heterogeneous (HG) blankets for improved sound reduction in aircraft structures. Phase I...

  8. The identification of major component of temu kunci (Kaemferia pandurata Roxb.) essential oils on different altitude

    OpenAIRE

    RETNA BANDRIATI ARNIPUTRI; AMALIA TETRANI SAKYA; MUJI RAHAYU

    2007-01-01

    The aims of this study was to know the major component of essential oils of Temu Kunci (Kaemferia pandurata Roxb.) on a different altitude. This research was carried out by method of Stahl destilation at BPTO and GCMS Cromatography at FMIPA UGM for both of from Kerjo (350 m asl) and Jumapolo (450 m asl). The difference of altitude of temu kunci’s lives on, the same of major component of essential oil but the content among them was different.

  9. An overview of the SCOUT-AMMA stratospheric aircraft, balloons and sondes campaign in West Africa, August 2006: rationale, roadmap and highlights

    Directory of Open Access Journals (Sweden)

    F. Cairo

    2009-09-01

    Full Text Available A multi-platform field measurement campaign involving aircraft and balloons took place over West Africa between 26 July and 25 August 2006, in the frame of the concomitant AMMA Special Observing Period and SCOUT-O3 African tropical activities.

    Specifically aiming at sampling the upper troposphere and lower stratosphere, the high-altitude research aircraft M55 Geophysica was deployed in Ouagadougou (12.3° N, 1.7° W, Burkina Faso, in conjunction with the German D-20 Falcon, while a series of stratospheric balloon and sonde flights were conducted from Niamey (13.5° N, 2.0° E, Niger.

    The stratospheric aircraft and balloon flights intended to gather experimental evidence for a better understanding of large scale transport, assessing the effect of lightning on NOx production, and studying the impact of intense mesoscale convective systems on water, aerosol, dust and chemical species in the upper troposphere and lower stratosphere. The M55 Geophysica carried out five local and four transfer flights between southern Europe and the Sahel and back, while eight stratospheric balloons and twenty-nine sondes were flown from Niamey.

    These experiments allowed a characterization of the tropopause and lower stratosphere of the region. We provide here an overview of the campaign activities together with a description of the general meteorological situation during the flights and a summary of the observations accomplished.

  10. Aircraft stress sequence development: A complex engineering process made simple

    Science.gov (United States)

    Schrader, K. H.; Butts, D. G.; Sparks, W. A.

    1994-01-01

    Development of stress sequences for critical aircraft structure requires flight measured usage data, known aircraft loads, and established relationships between aircraft flight loads and structural stresses. Resulting cycle-by-cycle stress sequences can be directly usable for crack growth analysis and coupon spectra tests. Often, an expert in loads and spectra development manipulates the usage data into a typical sequence of representative flight conditions for which loads and stresses are calculated. For a fighter/trainer type aircraft, this effort is repeated many times for each of the fatigue critical locations (FCL) resulting in expenditure of numerous engineering hours. The Aircraft Stress Sequence Computer Program (ACSTRSEQ), developed by Southwest Research Institute under contract to San Antonio Air Logistics Center, presents a unique approach for making complex technical computations in a simple, easy to use method. The program is written in Microsoft Visual Basic for the Microsoft Windows environment.

  11. 民机半实物仿真硬件接口系统设计研究%Design and Research of Civil Aircraft HIL Simulation Hardware Interface System

    Institute of Scientific and Technical Information of China (English)

    谢陵

    2011-01-01

    对民用飞机飞控系统的半实物仿真过程中所采用的硬件接口系统的功能、架构、组成等进行了设计和研究,并提供了硬件采购清单,该方案可以为各种半实物仿真实验系统提供高效、灵活的接口管理方案。%the article researches functions,architecture and constitution of the hardware interface system which is used in civil aircraft flight control system hard-in-loop simulation.And providing the hardware purchasing list.This article provide the efficient,flexible interface management solution for the hard-in-loop simulation system.

  12. Neutral Wind Observations below 200 km altitudes

    Science.gov (United States)

    Watanabe, S.; Abe, T.; Habu, H.; Kakinami, Y.; Larsen, M. F.; Pfaff, R. F., Jr.; Yamamoto, M.

    2015-12-01

    Neutral Wind Observations below 200 km altitudesS. Watanabe1, T. Abe2, H. Habu2, Y. Kakinami3, M. Larsen4, R. Pfaff5, M. Yamamoto6, M-Y. Yamamoto31Hokkaido University/Hokkaido Information University, 2JAXA/ISAS, 3Kochi University of Technology, 4Clemson University, 5NASA/Goddard Space Flight Center, 6Kyoto University, Neutral wind in the thermosphere is one of the key parameters to understand the ionosphere-thermosphere coupling process. JAXA/ISAS successfully launched sounding rockets from Uchinoura Space Center (USC) on September 2, 2007, January 12, 2012, and July 20, 2013, and NASA launched sounding rockets from Kwajalein on May 7, 2013 and from Wallops on July 4, 2013. The rockets installed Lithium and/or TMA canisters as well as instruments for plasma and electric and magnetic fields. The atomic Lithium gases were released at altitudes between 150 km and 300 km in the evening on September 2, 2007, at altitude of ~100 km in the morning on January 12, 2012, at altitude of ~120km in the midnight on July 20, 2013, at altitude between 150 km and 300 km in the evening on May 7, 2013 and at altitude of ~150 km in the noon on July 4, 2013. The Lithium atoms were scattering sunlight by resonance scattering with wavelength of 670nm. However, the Lithium atoms scattered moon light on July 20, 2013. The moon light scattering is the first time to use for thermospheric wind measurement in the midnight. The Lithium clouds/trails and TMA trails showed clearly the neutral wind shears and atmospheric waves at ~150 km altitude in the lower thermosphere for all local time.

  13. Atmospheric River Observations with the HAMSR Aircraft Microwave Sounder

    Science.gov (United States)

    Lambrigtsen, B.; Brown, S. T.; Schreier, M. M.; Dang, H. V. T.; Behrangi, A.

    2015-12-01

    The High Altitude MMIC Sounding Radiometer (HAMSR) was developed at the Jet Propulsion Laboratory in 2001 to serve as an aircraft based hurricane observatory. It initially flew on the high altitude ER-2 and later on the DC-8. More recently it was modified to fly on the Global Hawk UAV. It uses the most advanced technology and is among the most sensitive instruments of its kind. In addition to a number of NASA hurricane field campaigns - mostly in the North Atlantic, HAMSR has participated in two atmospheric river campaigns off the California coast, one in 2011 (WISPAR) and one in 2015 (CalWater2). We will discuss observations from the 2015 campaign, with particular focus on a flight over an atmsospheric river making landfall in central California in early February, as well as compare with highlights from the 2011 flights. Copyright 2015 California Institute of Technology. Government sponsorship acknowledged.

  14. Simulation Research of the Flexible Landing Gear's Falling Vibration Performance on an Aircraft%飞行器柔性起落架落震性能分析

    Institute of Scientific and Technical Information of China (English)

    王文强; 聂宏; 魏小辉; 王智成; 刘向尧

    2013-01-01

    以某型飞行器为原型,对该型飞行器进行了起落架缓冲器参数设计,并建立适用于ADAMS/Aircraft软件的起落架着陆性能仿真三维数字模型.进行了全刚性起落架全机落震仿真,验证起落架缓冲器初步设计结果基本满足落震缓冲性能要求.运用有限元软件对刚体起落架模型进行了柔性化处理,把起落架柔性因素考虑到缓冲性能分析中,建立简化数学模型对仿真结果加以分析验证.得出起落架柔性对缓冲器性能有一定影响的结论,并指出其影响的原因.对缓冲器参数设计具有指导意义.%By taking a certain type of aircraft as a prototype,it builds a three-dimensional digital simulation model.The model is based on ADAMS/Aircraft and focusing on the landing performance of landing gear.It carries falling vibration simulation of the rigid landing gear,and verifies that the designing results can meet the performance requirements of buffering the falling vibration.It also conducts flexible processing to the rigid landing gear by using finite element software.Furthermore,by taking flexibility into account in the analysis of cushioning performance of landing gear,it establishes a simplified mathematical model to verify the simulation results.It concludes that the flexible landing gear has an effect on the cushioning performance,and points out the effects of causes.It is of great guiding significance for the general parameter design of buffer.

  15. Retrieving Storm Electric Fields From Aircraft Field Mill Data. Part I: Theory

    Science.gov (United States)

    Koshak, W. J.

    2005-01-01

    It is shown that the problem of retrieving storm electric fields from an aircraft instrumented with several electric field mill sensors can be expressed in terms of a standard Lagrange multiplier optimization problem. The method naturally removes aircraft charge from the retrieval process without having to use a high voltage stinger and linearly combined mill data values. It also allows a variety of user-supplied physical constraints (the so-called side constraints in the theory of Lagrange multipliers). Additionally, this paper introduces a novel way of performing the absolute calibration of an aircraft that has several benefits over conventional analyses. In the new approach, absolute calibration is completed by inspecting the time derivatives of mill and pitch data for a pitch down maneuver performed at high (greater than 1 km) altitude. In Part II of this study, the above methods are tested and then applied to complete a full calibration of a Citation aircraft.

  16. Retrieving Storm Electric Fields from Aircraft Field Mill Data. Part 1; Theory

    Science.gov (United States)

    Koshak, W. J.

    2006-01-01

    It is shown that the problem of retrieving storm electric fields from an aircraft instrumented with several electric field mill sensors can be expressed in terms of a standard Lagrange multiplier optimization problem. The method naturally removes aircraft charge from the retrieval process without having to use a high voltage stinger and linearly combined mill data values. It allows a variety of user-supplied physical constraints (the so-called side constraints in the theory of Lagrange multipliers) and also helps improve absolute calibration. Additionally, this paper introduces an alternate way of performing the absolute calibration of an aircraft that has some benefits over conventional analyses. It is accomplished by using the time derivatives of mill and pitch data for a pitch down maneuver performed at high (greater than 1 km) altitude. In Part II of this study, the above methods are tested and then applied to complete a full calibration of a Citation aircraft.

  17. Lightweight Liquid Helium Dewar for High-Altitude Balloon Payloads

    Science.gov (United States)

    Kogut, Alan; James, Bryan; Fixsen, Dale

    2013-01-01

    Astrophysical observations at millimeter wavelengths require large (2-to-5- meter diameter) telescopes carried to altitudes above 35 km by scientific research balloons. The scientific performance is greatly enhanced if the telescope is cooled to temperatures below 10 K with no emissive windows between the telescope and the sky. Standard liquid helium bucket dewars can contain a suitable telescope for telescope diameter less than two meters. However, the mass of a dewar large enough to hold a 3-to-5-meter diameter telescope would exceed the balloon lift capacity. The solution is to separate the functions of cryogen storage and in-flight thermal isolation, utilizing the unique physical conditions at balloon altitudes. Conventional dewars are launched cold: the vacuum walls necessary for thermal isolation must also withstand the pressure gradient at sea level and are correspondingly thick and heavy. The pressure at 40 km is less than 0.3% of sea level: a dewar designed for use only at 40 km can use ultra thin walls to achieve significant reductions in mass. This innovation concerns new construction and operational techniques to produce a lightweight liquid helium bucket dewar. The dewar is intended for use on high-altitude balloon payloads. The mass is low enough to allow a large (3-to-5-meter) diameter dewar to fly at altitudes above 35 km on conventional scientific research balloons without exceeding the lift capability of the balloon. The lightweight dewar has thin (250- micron) stainless steel walls. The walls are too thin to support the pressure gradient at sea level: the dewar launches warm with the vacuum space vented continuously during ascent to eliminate any pressure gradient across the walls. A commercial 500-liter storage dewar maintains a reservoir of liquid helium within a minimal (hence low mass) volume. Once a 40-km altitude is reached, the valve venting the vacuum space of the bucket dewar is closed to seal the vacuum space. A vacuum pump then

  18. Obstacle avoidance and path planning for carrier aircraft launching

    Directory of Open Access Journals (Sweden)

    Wu Yu

    2015-06-01

    Full Text Available Launching safety and efficiency are important indexes to measure the fighting capacity of carrier. The study on path planning for taxi of carrier aircraft launching under actual deck environment is of great significance. In actual deck scheduling, manual command is applied to taxi of carrier aircraft, which has negative effects on the safety of staff and carrier aircraft launching. In consideration of both the safety and efficiency of carrier aircraft launching, the key elements of the problem are abstracted based on the analysis of deck environment, carrier aircraft maneuver performance and task requirements. According to the problem description, the mathematical model is established including various constraints. The carrier aircraft and the obstacles are reasonably simplified as circle and polygons respectively. What’s more, the proposed collision detection model reduces the calculations. Aimed at the features of model, the theory of model predictive control (MPC is applied to the path search. Then a dynamic weight heuristic function is designed and a dynamic multistep optimization algorithm is proposed. Taking the Nimitz-class aircraft carrier as an example, the paths from parking place to catapult are planned, which indicate the rationality of the model and the effectiveness of the algorithm by comparing the planning results under different simulation environments. The main contribution of research is the establishment of obstacle avoidance and path planning model. In addition, it provides the solution of model and technological foundations for comprehensive command and real-time decision-making of the carrier aircraft.

  19. Patients with Obstructive Sleep Apnea at Altitude.

    Science.gov (United States)

    Bloch, Konrad E; Latshang, Tsogyal D; Ulrich, Silvia

    2015-06-01

    Bloch, Konrad E., Tsogyal D. Latshang, and Silvia Ulrich. Patients with obstructive sleep apnea at altitude. High Alt Med Biol 16:110-116, 2015.--Obstructive sleep apnea (OSA) is highly prevalent in the general population, in particular in men and women of older age. In OSA patients sleeping near sea level, the apneas/hypopneas associated with intermittent hypoxemia are predominantly due to upper airway collapse. When OSA patients stay at altitudes above 1600 m, corresponding to that of many tourist destinations, hypobaric hypoxia promotes frequent central apneas in addition to obstructive events, resulting in combined intermittent and sustained hypoxia. This induces strong sympathetic activation with elevated heart rate, cardiac arrhythmia, and systemic hypertension. There are concerns that these changes expose susceptible OSA patients, in particular those with advanced age and co-morbidities, to an excessive risk of cardiovascular and other adverse events during a stay at altitude. Based on data from randomized trials, it seems advisable for OSA patients to use continuous positive airway pressure treatment with computer controlled mask pressure adjustment (autoCPAP) in combination with acetazolamide during an altitude sojourn. If CPAP therapy is not feasible, acetazolamide alone is better than no treatment at all, as it improves oxygenation and sleep apnea and prevents excessive blood pressure rises of OSA patients at altitude. PMID:25973669

  20. Can High Altitude Influence Cytokines and Sleep?

    Directory of Open Access Journals (Sweden)

    Valdir de Aquino Lemos

    2013-01-01

    Full Text Available The number of persons who relocate to regions of high altitude for work, pleasure, sport, or residence increases every year. It is known that the reduced supply of oxygen (O2 induced by acute or chronic increases in altitude stimulates the body to adapt to new metabolic challenges imposed by hypoxia. Sleep can suffer partial fragmentation because of the exposure to high altitudes, and these changes have been described as one of the responsible factors for the many consequences at high altitudes. We conducted a review of the literature during the period from 1987 to 2012. This work explored the relationships among inflammation, hypoxia and sleep in the period of adaptation and examined a novel mechanism that might explain the harmful effects of altitude on sleep, involving increased Interleukin-1 beta (IL-1β, Interleukin-6 (IL-6, and tumor necrosis factor-alpha (TNF-α production from several tissues and cells, such as leukocytes and cells from skeletal muscle and brain.

  1. Responses of the autonomic nervous system in altitude adapted and high altitude pulmonary oedema subjects

    Science.gov (United States)

    Mathew, Lazar; Purkayastha, S. S.; Jayashankar, A.; Radhakrishnan, U.; Sen Gupta, J.; Nayar, H. S.

    1985-06-01

    Studies were carried out to ascertain the role of sympatho-parasympathetic responses in the process of adaptation to altitude. The assessment of status of autonomic balance was carried out in a group of 20 young male subjects by recording their resting heart rate, blood pressure, oral temperature, mean skin temperature, extremity temperatures, pupillary diameter, cold pressor response, oxygen consumption, cardioacceleration during orthostasis and urinary excretion of catecholamines; in a thermoneutral laboratory. The same parameters were repeated on day 3 and at weekly intervals for a period of 3 weeks, after exposing them to 3,500 m; and also after return to sea level. At altitude, similar studies were carried out in a group of 10 acclimatized lowlanders, 10 high altitude natives and 6 patients who had recently recovered from high altitude pulmonary oedema. In another phase, similar studies were done in two groups of subjects, one representing 15 subjects who had stayed at altitude (3,500 4,000 m) without any ill effects and the other comprising of 10 subjects who had either suffered from high altitude pulmonary oedema (HAPO) or acute mountain sickness (AMS). The results revealed sympathetic overactivity on acute induction to altitude which showed gradual recovery on prolonged stay, the high altitude natives had preponderance to parasympathetic system. Sympathetic preponderance may not be an essential etiological factor for the causation of maladaptation syndromes.

  2. Research on parameter-dependent robust controller for unmanned aircraft%无人飞行器参数依赖鲁棒控制研究

    Institute of Scientific and Technical Information of China (English)

    支岳; 赵国荣; 宋超

    2012-01-01

    The problem of parameter-dependent robust controller design for unmanned aircraft with parameter uncertainties is investigated. The attitude dynamics is described by error quaternion to eliminate singularity of Euler angle description. By introducing some slack matrices, the proposed criterion exhibits a kind of separation between the system matrices and the positive definite Lyapunov matrices. The robust controller is designed through solving nonlinear matrices inequalities by using the sum of squares (SOS) toolkits in a reliable and efficient manner. Simulation results demonstrate the effectiveness and feasibility of the proposed approach.%研究了具有参数不确定性的无人飞行器参数依赖鲁棒控制器设计问题.采用误差四元数建立姿态运动方程,避免了欧拉角描述姿态运动存在奇异性的问题.通过引入附加的松弛矩阵使Lyapunov矩阵和系统矩阵分离,并利用平方和工具箱求解非线性矩阵不等式得到了系统的鲁棒控制器.仿真结果表明了所提出的控制器设计方法的可行性和有效性.

  3. Research on Flight Test Method for Evaluating Aircraft Cockpit Design%飞机座舱设计评估的试飞方法研究

    Institute of Scientific and Technical Information of China (English)

    封卫忠

    2014-01-01

    飞行试验是评估飞机座舱设计最好的方法,飞行试验阶段选取的评估方法应能获得全面的、足够的信息和来自用户有价值的反馈。本文在分析国内外用于座舱评估的人机工程标准的基础上,总结了用于座舱设计评估的基本方法和评估内容,介绍了用于座舱评估的工作负荷评价方法。%Flight test is the best method for evaluating aircraft cockpit design.The evaluation method selected during the flight test should obtain comprehensive and adequate information and valuable feedback from user.On the basis of analyzing human engineering standards for cockpit evaluation,the basic method and evaluation content are summarized and the workload evaluation method for cockpit design is introduced.

  4. Altitude Correction for Breakdown Voltages of Long Air-Gaps

    Institute of Scientific and Technical Information of China (English)

    Wang Xuan; Li Yunge; Cao Xiaolong; Su Zhiyi; Liu Ying

    2006-01-01

    The breakdown voltage of long air-gaps in high-voltage transmission systems depends on not only the waveform of the applied voltage, but also the atmospheric conditions. Based on the results of the research project on the minimum air clearance for 800-Kv HVDC substations at high altitudes, and also on the monthly and yearly statistics of the atmospheric data of last ten years and the altitude correction of the atmospheric data of last ten years, the altitude correction of the air-gaps for the 800-Kv DC system under plan, 500-Kv AC system to be built, and 1000-Kv AC system under plan in the Inner Mongolia Plateau and the Yungui Plateau in China were studied with parameter G method. Correction factors for switching and lightning impulses were calculated and then compared with those achieved according to IEC 71. It is shown that IEC 71 is appropriate for damp regions, and correction factors differ between plateau regions in China because of different atmospheric conditions.

  5. Atmospheric composition and thermodynamic retrievals from the ARIES airborne TIR-FTS system – Part 2: Validation and results from aircraft campaigns

    Directory of Open Access Journals (Sweden)

    G. Allen

    2014-04-01

    Full Text Available This study validates trace gas and thermodynamic retrievals from nadir infrared spectroscopic measurements recorded by the UK Met Office Airborne Research Interferometer Evaluation System (ARIES – a Thermal InfraRed Fourier Transform Spectrometer (TIR-FTS on the UK Facility for Airborne Atmospheric Measurements (FAAM BAe-146 aircraft. Trace-gas-concentration and thermodynamic profiles have been retrieved and validated for this study throughout the troposphere and planetary boundary layer over a range of environmental variability using data from aircraft campaigns over and around London, the US Gulf Coast, and the Arctic Circle during the ClearfLo, JAIVEX, and MAMM aircraft campaigns, respectively. Vertically-resolved retrievals of temperature and water vapour (H2O, and partial-column retrievals of methane (CH4, carbon monoxide (CO, and ozone (O3, over both land and sea, were compared to corresponding measurements from high-precision in-situ analysers and dropsondes operated on the FAAM aircraft. Average Degrees of Freedom for Signal (DOFS over a 0–9 km column range were found to be 4.97, 3.11, 0.91, 1.10, and 1.62 for temperature, H2O, CH4, CO, and O3, respectively, when retrieved on 10 vertical levels. Partial column mean biases (and 1σ bias averaged across all flight campaigns were −0.4 (±1.9%, −6.0 (±13.1%, −0.6 (±2.1%, −3.0(±18.4%, and +4.7 (±24.9%, respectively, while the typical total a posteriori errors for individually retrieved profiles were 0.4%, 9.5%, 5.0%, 21.2%, and 15.0%, respectively. Averaging kernels derived for progressively lower altitudes show improving sensitivity to lower atmospheric layers when flying at lower altitudes. Temperature and H2O display significant vertically resolved sensitivity throughout the column, whilst trace gases are usefully retrieved only as partial column quantities, with maximal sensitivity for trace gases other than H2O within a layer 1 km and 2 km below the aircraft. This study

  6. Sleep of Andean high altitude natives.

    Science.gov (United States)

    Coote, J H; Stone, B M; Tsang, G

    1992-01-01

    The structure of sleep in lowland visitors to altitudes greater than 4000 m is grossly disturbed. There are no data on sleep in long-term residents of high altitudes. This paper describes an electroencephalographic study of sleep in high altitude dwellers who were born in and are permanent residents of Cerro de Pasco in the Peruvian Andes, situated at 4330 m. Eight healthy male volunteers aged between 18 and 69 years were studied. Sleep was measured on three consecutive nights for each subject. Electroencephalographs, submental electromyographs and electro-oculograms were recorded. Only data from the third night were used in the analysis. The sleep patterns of these subjects resembled the normal sleep patterns described by others in lowlanders at sea level. There were significant amounts of slow wave sleep in the younger subjects and rapid eye movement sleep seemed unimpaired.

  7. Solar regenerative fuel cell system for high altitude airships

    International Nuclear Information System (INIS)

    'Full text': A closed-loop regenerative fuel cell (RFC) system that serves as an energy storage device for space activities is studied through dynamic simulations. The unique nature of the closed-loop RFC makes it an ideal power system for key applications in homeland defense and earth observatory systems such as high altitude aircrafts /airships, unmanned aerial vehicles, and in planetary exploration for flyer or for surface power. The RFC considered using the photovoltaic cells to produce electric power during the day, part of which is used to produce hydrogen and oxygen through electrolysis. The stored hydrogen and oxygen is used through a fuel cell to produce electric power during night hours. A MATLAB/SIMULINK model was developed for the components of the RFC that include a fuel cell, electrolyzer, photovoltaic solar array, power bus, humidifiers, compressor/motor assembly, expander, pumps, phase separators, storage tanks for hydrogen, oxygen and water, control valves and piping, electric grid system and controls. A proton exchange membrane (PEM) fuel cell and PEM electrolyzer were modeled in detail that included the mass momentum, energy, chemical reaction rates at cathode and anode. The PEM fuel cell voltage was modeled accounting cell activation and ohmic polarizations. A modular approach was used to develop models for each component. Component models were based on fundamental physics to the extent practical. Steady state and dynamic response of the RFC for different operational conditions including start-up, shut down, load changes and (accidental) transients was studied. (author)

  8. 飞机桁条-蒙皮连接结构的接触应力研究%Research on Contact Stress of Wing Stringers-Skin Connecting Structure in Aircraft

    Institute of Scientific and Technical Information of China (English)

    陈文俊; 周桂宇; 赵鲁春

    2015-01-01

    飞机结构是由零部件通过铆接、螺接、胶接和焊接连接而组成的。连接区域应力分布情况及应力水平的研究对飞机结构的强度校核及连接区的失效破坏形式的预判有着重要的意义。基于非线性接触力学理论,利用MSC. Pat-ran/Nastran有限元分析软件对机翼结构中复合材料桁条-蒙皮连接结构进行了研究。研究内容包括:各排钉孔的最大等效应力和钉传载荷的分布情况;对飞机桁条-蒙皮的两种连接方式,基于非线性接触理论,分别建立了桁条-蒙皮的螺接连接结构和胶-螺混合连接结构,对比了两种结构的等效应力水平大小与分布。得出以下结论:板间厚度比对孔周接触域的应力集中系数和应力分布的影响较大;处于外侧两排铆钉孔传递较大的钉传载荷,中间排的铆钉孔的钉传载荷较小;不同的连接形式对孔周应力水平影响较大。%Aircraft structures are formed by riveting, screwing, gluing and welding the connections and parts. Research of stress distribution and the stress level in the connected region of aircraft structures has great significance for strength check of aircraft structure and structural damage to connected region failures. Based on the nonlinear contact mechanics theory, the fi-nite element analysis software MSC. Patran/Nastran is used to investigate the aircraft connecting structure. The research in-cludes study on the distribution of maximum equivalent stress and the pin-load around the pin hole;the stringers-skin screw connecting structure and the glue-screw mixed connecting structure are respectively established based on the nonlinear contact theory, then the value and distribution of equivalent stress of these two kinds of connection modes are compared. The conclu-sion shows that the thickness ratio between plates has great influence on the stress concentration factor and stress distribution in the contact region around the

  9. 19 CFR 10.183 - Duty-free entry of civil aircraft, aircraft engines, ground flight simulators, parts, components...

    Science.gov (United States)

    2010-04-01

    ... Duty-free entry of civil aircraft, aircraft engines, ground flight simulators, parts, components, and... aircraft, aircraft engines, and ground flight simulators, including their parts, components, and... United States (HTSUS) by meeting the following requirements: (1) The aircraft, aircraft engines,...

  10. Compact survey and inspection day/night image sensor suite for small unmanned aircraft systems (EyePod)

    Science.gov (United States)

    Bird, Alan; Anderson, Scott A.; Linne von Berg, Dale; Davidson, Morgan; Holt, Niel; Kruer, Melvin; Wilson, Michael L.

    2010-04-01

    EyePod is a compact survey and inspection day/night imaging sensor suite for small unmanned aircraft systems (UAS). EyePod generates georeferenced image products in real-time from visible near infrared (VNIR) and long wave infrared (LWIR) imaging sensors and was developed under the ONR funded FEATHAR (Fusion, Exploitation, Algorithms, and Targeting for High-Altitude Reconnaissance) program. FEATHAR is being directed and executed by the Naval Research Laboratory (NRL) in conjunction with the Space Dynamics Laboratory (SDL) and FEATHAR's goal is to develop and test new tactical sensor systems specifically designed for small manned and unmanned platforms (payload weight < 50 lbs). The EyePod suite consists of two VNIR/LWIR (day/night) gimbaled sensors that, combined, provide broad area survey and focused inspection capabilities. Each EyePod sensor pairs an HD visible EO sensor with a LWIR bolometric imager providing precision geo-referenced and fully digital EO/IR NITFS output imagery. The LWIR sensor is mounted to a patent-pending jitter-reduction stage to correct for the high-frequency motion typically found on small aircraft and unmanned systems. Details will be presented on both the wide-area and inspection EyePod sensor systems, their modes of operation, and results from recent flight demonstrations.

  11. Research on the Limitations of Cooling Mechanism Based on FRM for Civil Aircraft%民用飞机冷却降燃方案的局限性研究

    Institute of Scientific and Technical Information of China (English)

    张斌

    2016-01-01

    The fuel tank flammability reduction means design for civil aircraft is an important part of fuel tank ex-plosion proof design, it is necessary to carry out the related research. By studying the 25. 981 airworthiness require-ments for civil aircraft, this paper summarizes the fuel tank flammability requirements and the corresponding FRM ( flammability reduction means) , and also studies the applicability of cooling mechanism based on FRM. The re-sults show that this concept has some limitations in actual application, especially it can’ t meet flammability airwor-thiness requirement for the fuel tank within the fuselage configuration.%民用飞机降低燃油箱可燃性设计是燃油箱防爆设计的一个重要方面,有必要对其开展相关研究。通过对民用飞机燃油箱25.981适航条款要求的解读,总结了适航对燃油箱可燃性要求以及对应的降低燃油箱可燃性措施( FRM),并对基于冷却降燃方案的适用性进行分析研究,研究结果表明该方案在实际应用中具有一定局限性,尤其是无法满足位于机身内非主燃油箱的可燃性适航要求。

  12. Research on Aerial Survey System Technology of UAV Borne Double Camera Low Altitude%无人机载双拼相机低空航测系统技术研究

    Institute of Scientific and Technical Information of China (English)

    王妍; 朱岩隆; 高伟; 付兴举

    2014-01-01

    目前国内大多数无人机航测系统所采用的单相机平面精度可达到要求,但高程精度无法满足大比例尺测图要求。本文主要介绍一种无人机载双拼组合宽角相机低空航测系统,其组成结构、双拼组合宽角数码相机原理、数据处理软件,以及利用该系统进行大比例尺测图的生产流程。它与单相机系统的最大不同点是,通过双拼组合扩大了成像系统的旁向视场角,使得在等同航高条件下,航带影像地面覆盖宽度增加一倍,从而达到提高效率的目的。%Single camera plane precision of the majority of the current domestic UAV aerial used by the system can meet the require -ments of, but the elevation accuracy cannot meet the requirements of large scale mapping .This paper mainly introduces a kind of un-manned airborne dual combination of wide angle of Low Altitude Aerial Camera system .Its structure, dual combination of wide angle digital camera principle , data processing software and the use of the system for large scale mapping production process .It is the big-gest difference with the single camera system , the dual combination of extended imaging system next to the viewing angle , the equiva-lent air condition , and strip image ground cover width increase one times , so as to achieve the purpose of improving the efficiency .

  13. 低空无人机双介质水下礁盘深度测量试验与分析%Research of Two-media Underwater Reefs Depth Measurement Experiment Based on Low-altitude UAV

    Institute of Scientific and Technical Information of China (English)

    周高伟; 李英成; 任延旭; 盛琳; 叶冬梅; 范凤云; 白洁

    2015-01-01

    以双介质摄影测量原理为基础,利用海岛无人机影像开展了航空双介质摄影测量试验与分析。首先简单介绍了双介质摄影测量原理,论述了双介质摄影测量对海水折射率的精度要求,提出了一种解算高程改正系数方法,在此基础上开展了基于某岛低空无人机影像的双介质水下礁盘深度量测试验。试验表明,航空双介质摄影测量在实际应用中是可行的,对航空摄影条件要求比较高。%Based on the principle of two-media photogrammetry and with islands UAV images,a test of two-media photogrammetry is carried out.Fi rstly,there is an introduction of the principle of two-media photogram-metry.In the fol lowing step,the two-media photogrammetry requi rements on the accuracy of the refractive index of sea water is discussed.Then,a new method for calculating the elevation correction coefficient is developed.The test procedure of two-media underwater reefs depth measurement based on low-altitude UAV images of underwater reefs surrounding the islands is designed.The test shows that aerial two-media photogram-metry is feasible in practical appl ication,but relatively high requi rements for aerial photography conditions.

  14. Atmospheric CO{sub 2} concentrations the CSIRO (Australia) monitoring program from aircraft 1972 - 1981

    Energy Technology Data Exchange (ETDEWEB)

    Beardsmore, D.J.; Pearman, G.I. [Commonwealth Scientific Industrial Research Organization (CSIRO), Victoria (Australia). Division of Atmospheric Research

    1984-09-01

    Atmospheric CO{sub 2} concentrations were measured in the troposphere and lower stratosphere over the Australia-New Zealand region and as far south as Antarctica for the period 1972-1981. The samples were collected from aircraft over a large range of latitudes and altitudes. The sampling program has been based on the cooperation of the Australia Department of Transport, Quantas Airways, Trans Australia Airlines, the United States, New Zealand and Australian Air Forces and occasional chartering of light aircraft for special purposes.

  15. Model analysis of the chemical conversion of exhaust species in the expanding plumes of subsonic aircraft

    Energy Technology Data Exchange (ETDEWEB)

    Moellhoff, M.; Hendricks, J.; Lippert, E.; Petry, H. [Koeln Univ. (Germany). Inst. fuer Geophysik und Meteorologie; Sausen, R. [Deutsche Forschungsanstalt fuer Luft- und Raumfahrt e.V. (DLR), Oberpfaffenhofen (Germany). Inst. fuer Physik der Atmosphaere

    1997-12-31

    A box model and two different one-dimensional models are used to investigate the chemical conversion of exhaust species in the dispersing plume of a subsonic aircraft flying at cruise altitude. The effect of varying daytime of release as well as the impact of changing dispersion time is studied with special respect to the aircraft induced O{sub 3} production. Effective emission amounts for consideration in mesoscale and global models are calculated. Simulations with modified photolysis rates are performed to show the sensitivity of the photochemistry to the occurrence of cirrus clouds. (author) 8 refs.

  16. Automation tools for flexible aircraft maintenance.

    Energy Technology Data Exchange (ETDEWEB)

    Prentice, William J.; Drotning, William D.; Watterberg, Peter A.; Loucks, Clifford S.; Kozlowski, David M.

    2003-11-01

    This report summarizes the accomplishments of the Laboratory Directed Research and Development (LDRD) project 26546 at Sandia, during the period FY01 through FY03. The project team visited four DoD depots that support extensive aircraft maintenance in order to understand critical needs for automation, and to identify maintenance processes for potential automation or integration opportunities. From the visits, the team identified technology needs and application issues, as well as non-technical drivers that influence the application of automation in depot maintenance of aircraft. Software tools for automation facility design analysis were developed, improved, extended, and integrated to encompass greater breadth for eventual application as a generalized design tool. The design tools for automated path planning and path generation have been enhanced to incorporate those complex robot systems with redundant joint configurations, which are likely candidate designs for a complex aircraft maintenance facility. A prototype force-controlled actively compliant end-effector was designed and developed based on a parallel kinematic mechanism design. This device was developed for demonstration of surface finishing, one of many in-contact operations performed during aircraft maintenance. This end-effector tool was positioned along the workpiece by a robot manipulator, programmed for operation by the automated planning tools integrated for this project. Together, the hardware and software tools demonstrate many of the technologies required for flexible automation in a maintenance facility.

  17. The Extrapolation of High Altitude Solar Cell I(V) Characteristics to AM0

    Science.gov (United States)

    Snyder, David B.; Scheiman, David A.; Jenkins, Phillip P.; Reinke, William; Blankenship, Kurt; Demers, James

    2007-01-01

    The high altitude aircraft method has been used at NASA GRC since the early 1960's to calibrate solar cell short circuit current, ISC, to Air Mass Zero (AMO). This method extrapolates ISC to AM0 via the Langley plot method, a logarithmic extrapolation to 0 air mass, and includes corrections for the varying Earth-Sun distance to 1.0 AU and compensating for the non-uniform ozone distribution in the atmosphere. However, other characteristics of the solar cell I(V) curve do not extrapolate in the same way. Another approach is needed to extrapolate VOC and the maximum power point (PMAX) to AM0 illumination. As part of the high altitude aircraft method, VOC and PMAX can be obtained as ISC changes during the flight. These values can then the extrapolated, sometimes interpolated, to the ISC(AM0) value. This approach should be valid as long as the shape of the solar spectra in the stratosphere does not change too much from AMO. As a feasibility check, the results are compared to AMO I(V) curves obtained using the NASA GRC X25 based multi-source simulator. This paper investigates the approach on both multi-junction solar cells and sub-cells.

  18. Mission management aircraft operations manual

    Science.gov (United States)

    1992-01-01

    This manual prescribes the NASA mission management aircraft program and provides policies and criteria for the safe and economical operation, maintenance, and inspection of NASA mission management aircraft. The operation of NASA mission management aircraft is based on the concept that safety has the highest priority. Operations involving unwarranted risks will not be tolerated. NASA mission management aircraft will be designated by the Associate Administrator for Management Systems and Facilities. NASA mission management aircraft are public aircraft as defined by the Federal Aviation Act of 1958. Maintenance standards, as a minimum, will meet those required for retention of Federal Aviation Administration (FAA) airworthiness certification. Federal Aviation Regulation Part 91, Subparts A and B, will apply except when requirements of this manual are more restrictive.

  19. CAPACITY CALCULATION OF TD-CDMA HIGH ALTITUDE PLATFORM SYSTEM

    Institute of Scientific and Technical Information of China (English)

    Wang Zhenyong; Liu Xiaowei; Li Zhuoshi

    2011-01-01

    A capacity calculation method of High Altitude Platform System (HAPS) is proposed in which TD-CDMA multiple access schemes are applied.With the influence of both power limit and bandwidth limit on capacity integrated,the paper derives the equations by which the capacity of TD-CDMA systems can be calculated,and performs calculation on a practical system.This calculation method is quite simple and effective with a comparatively small error,which is essential to the designing and research on HAPS.

  20. 19 CFR 122.64 - Other aircraft.

    Science.gov (United States)

    2010-04-01

    ... 19 Customs Duties 1 2010-04-01 2010-04-01 false Other aircraft. 122.64 Section 122.64 Customs... AIR COMMERCE REGULATIONS Clearance of Aircraft and Permission To Depart § 122.64 Other aircraft. Clearance or permission to depart shall be requested by the aircraft commander or agent for aircraft...

  1. Energy supply and its effect on aircraft of the future. II - Liquid-hydrogen-fueled aircraft: Prospects and design issues.

    Science.gov (United States)

    Kirkham, F. S.; Driver, C.

    1973-01-01

    The performance of hydrogen-fueled commercial aircraft is examined in the subsonic, supersonic, and hypersonic speed regime and compared with JP-fueled systems. Hydrogen aircraft are shown to provide substantial improvements in range and payload fraction as well as to minimize or eliminate many environmental problems. The major elements of a development program required to make hydrogen-fueled aircraft a commercial reality are also outlined and the rationale for and characteristics of both a subsonic demonstrator and a high speed research airplane are described.

  2. Guidance Systems of Fighter Aircraft

    Directory of Open Access Journals (Sweden)

    K.N. Rajanikanth

    2005-07-01

    Full Text Available Mission performance of a fighter aircraft is crucial for survival and strike capabilities in todays' aerial warfare scenario. The guidance functions of such an aircraft play a vital role inmeeting the requirements and accomplishing the mission success. This paper presents the requirements of precision guidance for various missions of a fighter aircraft. The concept ofguidance system as a pilot-in-loop system is pivotal in understanding and designing such a system. Methodologies of designing such a system are described.

  3. Long-range pollution transport during the MILAGRO-2006 campaign: a case study of a major Mexico City outflow event using free-floating altitude-controlled balloons

    Energy Technology Data Exchange (ETDEWEB)

    Voss, Paul B.; Zaveri, Rahul A.; Flocke, Frank M.; Mao, Huitimg; Hartley, Tom; DeAmicis, Pam; Deonandan, Indira; Contrerars-Jimenez, G.; Martinez-Antonio, O.; Figueroa Estrada, M.; Greenberg, David; Campos, Teresa; Weinheimer, Andrew J.; Knapp, David; Montzka, DeeDee; Crounse, J. D.; Wennberg, P. O.; Apel, Eric; Madronich, Sasha; de Foy, B.

    2010-08-04

    One of the major objectives of the Megacities Initiative: Local And Global Research 3 Observations (MILAGRO 2006) campaign was to investigate the long-range transport of 4 Mexico City Metropolitan Area (MCMA) pollution outflow and its downwind impacts on air 5 quality and climate. Four aircraft (DOE G-1, NSF/NCAR C-130, NASA-J31, and NASA 6 DC-8) made extensive chemical, aerosol, and radiation measurements above MCMA and over 7 1000 km downwind in order to characterize the evolution of MCMA pollution as it aged and 8 dispersed over the central Mexican plateau and the Gulf of Mexico. As part of this effort, 9 free-floating Controlled-Meteorological (CMET) balloons, capable of changing altitude on 10 command via satellite, characterized the MCMA outflow by performing repeated soundings 11 during the transit. In this paper, we present an analysis based on the data from two CMET 12 balloons that were launched near Mexico City on the afternoon of 18 March 2006 and floated 13 downwind with the outflow for nearly 30 hours. Continuous profile measurements made by 14 the balloons show the evolving structure of the MCMA outflow in considerable detail: its 15 stability and stratification, interaction with other air masses, mixing episodes, and dispersion 16 into the regional background. Air parcel trajectories, computed directly from the balloon 17 wind profiles, show three different transport pathways for Mexico City outflow on 18-19 18 March: (a) high-altitude advection of the top of the MCMA mixed layer, (b) low-altitude flow 19 over the Sierra Madre Oriental followed by decoupling and isolated transport over the Gulf, 20 and (c) the same decoupling scenario with entrainment into a cleaner westerly jet below the 21 plateau. The C-130 intercepted the balloon-based trajectories three times on 19 March, once 22 along each transport pathway. In all three cases, distinct peaks in the urban tracer signature 23 and LIDAR backscatter imagery provided evidence for Mexico City air

  4. Airborne research in cool regions

    OpenAIRE

    Steinhage, Daniel

    2010-01-01

    The Alfred Wegener Institute uses ski-equipped aircraft to support and to conduct its research activities both polar regions since 1983 and provides access to the aircraft to the German scientific community. Beside logistic support of field groups, the aircraft were utilized in glaciology, geophysics, meteorology, and physics of the atmosphere. At the beginning Dornier aircraft, first POLAR 1, a Do128, and POLAR 2, a Do228, followed by two Dornier aircraft of typ Do228 were used. While one ai...

  5. Aircraft Recirculation Filter for Air-Quality and Incident Assessment

    OpenAIRE

    Eckels, Steven J.; Jones, Byron; Mann, Garrett; Mohan, Krishnan R.; Weisel, Clifford P.

    2014-01-01

    The current research examines the possibility of using recirculation filters from aircraft to document the nature of air-quality incidents on aircraft. These filters are highly effective at collecting solid and liquid particulates. Identification of engine oil contaminants arriving through the bleed air system on the filter was chosen as the initial focus. A two-step study was undertaken. First, a compressor/bleed air simulator was developed to simulate an engine oil leak, and samples were an...

  6. Active flow control systems architectures for civil transport aircraft

    OpenAIRE

    Jabbal, M; Liddle, SC; Crowther, WJ

    2010-01-01

    Copyright @ 2010 American Institute of Aeronautics and Astronautics This paper considers the effect of choice of actuator technology and associated power systems architecture on the mass cost and power consumption of implementing active flow control systems on civil transport aircraft. The research method is based on the use of a mass model that includes a mass due to systems hardware and a mass due to the system energy usage. An Airbus A320 aircraft wing is used as a case-study applicatio...

  7. High altitude pulmonary edema among "Amarnath Yatris"

    Directory of Open Access Journals (Sweden)

    Parvaiz A Koul

    2013-01-01

    Full Text Available Background: Annual pilgrimage (Yatra to the cave shrine of Shri Amarnath Ji′ is a holy ritual among the Hindu devotees of Lord Shiva. Located in the Himalayan Mountain Range (altitude 13,000 ft in south Kashmir, the shrine is visited by thousands of devotees and altitude sickness is reportedly common. Materials and Methods: More than 600,000 pilgrims visited the cave shrine in 2011 and 2012 with 239 recorded deaths. Thirty one patients with suspected altitude sickness were referred from medical centers en-route the cave to Sher-i-Kashmir Institute of Medical Sciences, a tertiary-care center in capital Srinagar (5,000 ft. The clinical features and the response to treatment were recorded. Results: Thirty-one patients (all lowlanders, 19 male; age 18-60 years, median 41 had presented with acute onset breathlessness of 1-4 days (median 1.9 d starting within 12-24 h of a rapid ascent; accompanied by cough (68%, headache (8%, dizziness and nausea (65%. Sixteen patients had associated encephalopathy. Clinical features on admission included tachypnea ( n = 31, tachycardia ( n = 23, bilateral chest rales ( n = 29, cyanosis ( n = 22 and grade 2-4 encephalopathy. Hypoxemia was demonstrable in 24 cases and bilateral infiltrates on radiologic imaging in 29. Ten patients had evidence of high-altitude cerebral edema. All patients were managed with oxygen, steroids, nifedipine, sildenafil and other supportive measures including invasive ventilation ( n = 3. Three patients died due to multiorgan dysfunction. Conclusions: Altitude sickness is common among Amaranath Yatris from the plains and appropriate educational strategies should be invoked for prevention and prompt treatment.

  8. Estimation of high altitude Martian dust parameters

    Science.gov (United States)

    Pabari, Jayesh; Bhalodi, Pinali

    2016-07-01

    Dust devils are known to occur near the Martian surface mostly during the mid of Southern hemisphere summer and they play vital role in deciding background dust opacity in the atmosphere. The second source of high altitude Martian dust could be due to the secondary ejecta caused by impacts on Martian Moons, Phobos and Deimos. Also, the surfaces of the Moons are charged positively due to ultraviolet rays from the Sun and negatively due to space plasma currents. Such surface charging may cause fine grains to be levitated, which can easily escape the Moons. It is expected that the escaping dust form dust rings within the orbits of the Moons and therefore also around the Mars. One more possible source of high altitude Martian dust is interplanetary in nature. Due to continuous supply of the dust from various sources and also due to a kind of feedback mechanism existing between the ring or tori and the sources, the dust rings or tori can sustain over a period of time. Recently, very high altitude dust at about 1000 km has been found by MAVEN mission and it is expected that the dust may be concentrated at about 150 to 500 km. However, it is mystery how dust has reached to such high altitudes. Estimation of dust parameters before-hand is necessary to design an instrument for the detection of high altitude Martian dust from a future orbiter. In this work, we have studied the dust supply rate responsible primarily for the formation of dust ring or tori, the life time of dust particles around the Mars, the dust number density as well as the effect of solar radiation pressure and Martian oblateness on dust dynamics. The results presented in this paper may be useful to space scientists for understanding the scenario and designing an orbiter based instrument to measure the dust surrounding the Mars for solving the mystery. The further work is underway.

  9. Can aneroid sphygmomanometers be used at altitude?

    Science.gov (United States)

    Kametas, N A; McAuliffe, F; Krampl, E; Nicolaides, K H; Shennan, A H

    2006-07-01

    Mercury-independent devices are increasingly being used in clinical practice as mercury will soon be removed from clinical use as a result of environmental, health and safety concerns. The aim of this study was to evaluate the accuracy of a portable aneroid device in an adult population at high altitude by following the part of the protocol of the British Hypertension Society regarding comparison between device and observer. We examined 10 subjects in Cerro de Pasco, Peru, which is situated 4370 m above sea level. The aneroid device was initially calibrated at both high altitude and at sea level to ensure optimal function. Validation of the device was undertaken at high altitude by connecting it in parallel to two mercury sphygmomanometers. Eleven sequential same-arm measurements were taken from each subject by two trained observers, alternating between mercury sphygmomanometry and the aneroid device. Simultaneous mercury readings were also recorded for additional analysis. During calibration, all 60 comparisons between the aneroid and mercury sphygmomanometers were within 3 mm Hg both at sea level and at high altitude. At validation, the device achieved an A grade for both systolic and diastolic pressures and also fulfilled the requirements of the Association for the Advancement of Medical Instrumentation. The mean and standard deviation for systolic and diastolic pressures, respectively, were -1.32 (4.3) mm Hg and 3.7 (4.7) mm Hg in sequential analysis and -0.7 (2.6) mm Hg and -3.3 (2.7) mm Hg in simultaneous analysis. We conclude that the Riester-Exacta portable aneroid device can be recommended for use in an adult population at high altitude.

  10. Digital adaptive control laws for VTOL aircraft

    Science.gov (United States)

    Hartmann, G. L.; Stein, G.

    1979-01-01

    Honeywell has designed a digital self-adaptive flight control system for flight test in the VALT Research Aircraft (a modified CH-47). The final design resulted from a comparison of two different adaptive concepts: one based on explicit parameter estimates from a real-time maximum likelihood estimation algorithm and the other based on an implicit model reference adaptive system. The two designs are compared on the basis of performance and complexity.

  11. Aircraft measurements of gravity waves in the upper troposphere and lower stratosphere during the START08 Field Experiment

    Directory of Open Access Journals (Sweden)

    Fuqing Zhang

    2015-02-01

    Full Text Available This study analyzes in situ airborne measurements from the 2008 Stratosphere–Troposphere Analyses of Regional Transport (START08 experiment to characterize gravity waves in the extratropical upper troposphere and lower stratosphere (ExUTLS region. The focus is on the second research flight (RF02, which took place on 21–22 April 2008. This was the first airborne mission dedicated to probing gravity waves associated with strong upper-tropospheric jet-front systems. Based on spectral and wavelet analyses of the in situ observations, along with a diagnosis of the polarization relationships, clear signals of mesoscale variations with wavelengths ~50–500 km are found in almost every segment of the 8 h flight, which took place mostly in the lower stratosphere. The aircraft sampled a wide range of background conditions including the region near the jet core, the jet exit and over the Rocky Mountains. In contrast to the long wavelength mesoscale variations, smaller-scale wavelike oscillations below 50 km are found to be quite transient. In particular, aircraft measurements of several flight segments are dominated by signals with periods of ~20– ~60 s and wavelengths of ~5– ~15 km. We speculate that at least part of these nearly-periodic high-frequency signals are a result of intrinsic observational errors in the aircraft measurements or small-scale flight-altitude fluctuations that are difficult to fully characterize. Despite the presence of possibly spurious wave oscillations in several flight segments, the power spectra of horizontal winds and temperature averaged over the analyzed START08 flight segments follow closely the -5/3 power law.

  12. Wind Information Uplink to Aircraft Performing Interval Management Operations

    Science.gov (United States)

    Ahmad, Nashat N.; Barmore, Bryan E.; Swieringa, Kurt A.

    2016-01-01

    Interval Management (IM) is an ADS-B-enabled suite of applications that use ground and flight deck capabilities and procedures designed to support the relative spacing of aircraft (Barmore et al., 2004, Murdoch et al. 2009, Barmore 2009, Swieringa et al. 2011; Weitz et al. 2012). Relative spacing refers to managing the position of one aircraft to a time or distance relative to another aircraft, as opposed to a static reference point such as a point over the ground or clock time. This results in improved inter-aircraft spacing precision and is expected to allow aircraft to be spaced closer to the applicable separation standard than current operations. Consequently, if the reduced spacing is used in scheduling, IM can reduce the time interval between the first and last aircraft in an overall arrival flow, resulting in increased throughput. Because IM relies on speed changes to achieve precise spacing, it can reduce costly, low-altitude, vectoring, which increases both efficiency and throughput in capacity-constrained airspace without negatively impacting controller workload and task complexity. This is expected to increase overall system efficiency. The Flight Deck Interval Management (FIM) equipment provides speeds to the flight crew that will deliver them to the achieve-by point at the controller-specified time, i.e., assigned spacing goal, after the target aircraft crosses the achieve-by point (Figure 1.1). Since the IM and target aircraft may not be on the same arrival procedure, the FIM equipment predicts the estimated times of arrival (ETA) for both the IM and target aircraft to the achieve-by point. This involves generating an approximate four-dimensional trajectory for each aircraft. The accuracy of the wind data used to generate those trajectories is critical to the success of the IM operation. There are two main forms of uncertainty in the wind information used by the FIM equipment. The first is the accuracy of the forecast modeling done by the weather

  13. Chemistry in aircraft plumes

    Energy Technology Data Exchange (ETDEWEB)

    Kraabol, A.G.; Stordal, F.; Knudsen, S. [Norwegian Inst. for Air Research, Kjeller (Norway); Konopka, P. [Deutsche Forschungsanstalt fuer Luft- und Raumfahrt e.V. (DLR), Wessling (Germany). Inst. fuer Physik der Atmosphaere

    1997-12-31

    An expanding plume model with chemistry has been used to study the chemical conversion of NO{sub x} to reservoir species in aircraft plumes. The heterogeneous conversion of N{sub 2}O{sub 5} to HNO{sub 3}(s) has been investigated when the emissions take place during night-time. The plume from an B747 has been simulated. During a ten-hour calculation the most important reservoir species was HNO{sub 3} for emissions at noon. The heterogeneous reactions had little impact on the chemical loss of NO{sub x} to reservoir species for emissions at night. (author) 4 refs.

  14. Hydrogen aircraft technology

    Science.gov (United States)

    Brewer, G. D.

    1991-01-01

    A comprehensive evaluation is conducted of the technology development status, economics, commercial feasibility, and infrastructural requirements of LH2-fueled aircraft, with additional consideration of hydrogen production, liquefaction, and cryostorage methods. Attention is given to the effects of LH2 fuel cryotank accommodation on the configurations of prospective commercial transports and military airlifters, SSTs, and HSTs, as well as to the use of the plentiful heatsink capacity of LH2 for innovative propulsion cycles' performance maximization. State-of-the-art materials and structural design principles for integral cryotank implementation are noted, as are airport requirements and safety and environmental considerations.

  15. Remotely piloted aircraft systems as a rhinoceros anti-poaching tool in Africa.

    Directory of Open Access Journals (Sweden)

    Margarita Mulero-Pázmány

    Full Text Available Over the last years there has been a massive increase in rhinoceros poaching incidents, with more than two individuals killed per day in South Africa in the first months of 2013. Immediate actions are needed to preserve current populations and the agents involved in their protection are demanding new technologies to increase their efficiency in the field. We assessed the use of remotely piloted aircraft systems (RPAS to monitor for poaching activities. We performed 20 flights with 3 types of cameras: visual photo, HD video and thermal video, to test the ability of the systems to detect (a rhinoceros, (b people acting as poachers and (c to do fence surveillance. The study area consisted of several large game farms in KwaZulu-Natal province, South Africa. The targets were better detected at the lowest altitudes, but to operate the plane safely and in a discreet way, altitudes between 100 and 180 m were the most convenient. Open areas facilitated target detection, while forest habitats complicated it. Detectability using visual cameras was higher at morning and midday, but the thermal camera provided the best images in the morning and at night. Considering not only the technical capabilities of the systems but also the poacherś modus operandi and the current control methods, we propose RPAS usage as a tool for surveillance of sensitive areas, for supporting field anti-poaching operations, as a deterrent tool for poachers and as a complementary method for rhinoceros ecology research. Here, we demonstrate that low cost RPAS can be useful for rhinoceros stakeholders for field control procedures. There are, however, important practical limitations that should be considered for their successful and realistic integration in the anti-poaching battle.

  16. Remotely piloted aircraft systems as a rhinoceros anti-poaching tool in Africa.

    Science.gov (United States)

    Mulero-Pázmány, Margarita; Stolper, Roel; van Essen, L D; Negro, Juan J; Sassen, Tyrell

    2014-01-01

    Over the last years there has been a massive increase in rhinoceros poaching incidents, with more than two individuals killed per day in South Africa in the first months of 2013. Immediate actions are needed to preserve current populations and the agents involved in their protection are demanding new technologies to increase their efficiency in the field. We assessed the use of remotely piloted aircraft systems (RPAS) to monitor for poaching activities. We performed 20 flights with 3 types of cameras: visual photo, HD video and thermal video, to test the ability of the systems to detect (a) rhinoceros, (b) people acting as poachers and (c) to do fence surveillance. The study area consisted of several large game farms in KwaZulu-Natal province, South Africa. The targets were better detected at the lowest altitudes, but to operate the plane safely and in a discreet way, altitudes between 100 and 180 m were the most convenient. Open areas facilitated target detection, while forest habitats complicated it. Detectability using visual cameras was higher at morning and midday, but the thermal camera provided the best images in the morning and at night. Considering not only the technical capabilities of the systems but also the poacherś modus operandi and the current control methods, we propose RPAS usage as a tool for surveillance of sensitive areas, for supporting field anti-poaching operations, as a deterrent tool for poachers and as a complementary method for rhinoceros ecology research. Here, we demonstrate that low cost RPAS can be useful for rhinoceros stakeholders for field control procedures. There are, however, important practical limitations that should be considered for their successful and realistic integration in the anti-poaching battle. PMID:24416177

  17. SR-71 Research Engineer Marta Bohn-Meyer

    Science.gov (United States)

    1992-01-01

    This 1992 photo shows SR-71 flight engineer Marta Bohn-Meyer in front of one of NASA's SR-71 aircraft on the ramp at the Ames-Dryden Flight Research Facility (later, Dryden Flight Research Center), Edwards, California. An aerospace engineer who has been at Dryden since 1979, Bohn-Meyer is the first female crew member ever assigned to fly in the SR-71. Data from the SR-71 program carried out by NASA will be used to aid designers of future supersonic aircraft and propulsion systems. Two SR-71 aircraft have been used by NASA as testbeds for high-speed and high-altitude aeronautical research. The aircraft, an SR-71A and an SR-71B pilot trainer aircraft, have been based here at NASA's Dryden Flight Research Center, Edwards, California. They were transferred to NASA after the U.S. Air Force program was cancelled. As research platforms, the aircraft can cruise at Mach 3 for more than one hour. For thermal experiments, this can produce heat soak temperatures of over 600 degrees Fahrenheit (F). This operating environment makes these aircraft excellent platforms to carry out research and experiments in a variety of areas -- aerodynamics, propulsion, structures, thermal protection materials, high-speed and high-temperature instrumentation, atmospheric studies, and sonic boom characterization. The SR-71 was used in a program to study ways of reducing sonic booms or over pressures that are heard on the ground, much like sharp thunderclaps, when an aircraft exceeds the speed of sound. Data from this Sonic Boom Mitigation Study could eventually lead to aircraft designs that would reduce the 'peak' overpressures of sonic booms and minimize the startling affect they produce on the ground. One of the first major experiments to be flown in the NASA SR-71 program was a laser air data collection system. It used laser light instead of air pressure to produce airspeed and attitude reference data, such as angle of attack and sideslip, which are normally obtained with small tubes and vanes

  18. Variation in airborne 137Cs peak levels with altitude from high-altitude locations across Europe after the arrival of Fukushima-labeled air masses

    Science.gov (United States)

    Masson, Olivier; Bieringer, Jacqueline; Dalheimer, Axel; Estier, Sybille; Evrard, Olivier; Penev, Ilia; Ringer, Wolfgang; Schlosser, Clemens; Steinkopff, Thomas; Tositti, Laura; de Vismes-Ott, Anne

    2015-04-01

    During the Fukushima Daiichi nuclear power plant (FDNPP) accident, a dozen of high-altitude aerosol sampling stations, located between 850 and 3,454 m above sea level (a.s.l.), provided airborne activity levels across Europe (Fig. 1). This represents at most 5% of the total number of aerosol sampling locations that delivered airborne activity levels (at least one result) in Europe, in connection with this nuclear accident. High altitude stations are typically equipped with a high volume sampler that collects aerosols on filters. The Fukushima-labeled air mass arrival and the peak of airborne cesium-137 (137Cs) activity levels were registered in Europe at different dates depending on the location, with differences up to a factor of six on a regional scale. Besides this statement related to lowland areas, we have compared the maximum airborne levels registered at high-altitude European locations (850 m dynamic of air movements at such high altitudes. After the 137Cs peak value, the plume concentration decreased whatever the 7Be level. Due to the cosmogenic origin of 7Be, its increase in the ground-level air is usually associated with downwind air movements, i.e. stratospheric air intrusions or at least air from high-tropospheric levels, into lower atmospheric layers. This means that Fukushima-labeled air masses registered at ground level were transported until Europe at rather high altitudes. This is consistent with 137Cs activity levels and 133Xe observations performed at the tropopause level thanks to aircraft samples over Germany and Switzerland (Estier and Steinmann). This also validates dispersion model computation according to which the Fukushima-labeled air masses were transported to Europe above 5500 m a.s.l. Conclusions : High altitude locations are on 'sentry duty' for radioactive monitoring and cross-border spreading of a contaminated plume. In this sense they can provide useful information on the vertical spreading of radionuclides, reveal arrival times

  19. Aircraft measurements of aerosol black carbon from a coastal location in the north-east part of peninsular India during ICARB

    Indian Academy of Sciences (India)

    S Suresh Babu; S K Satheesh; K Krishna Moorthy; C B S Dutt; Vijayakumar S Nair; Denny P Alappattu; P K Kunhikrishnan

    2008-07-01

    During the Integrated Campaign for Aerosols, gases and Radiation Budget (ICARB) over India, high-resolution airborne measurements of the altitude profiles of the mass concentrations (MB) of aerosol black carbon (BC) were made off Bhubaneswar (BBR, 85.82°E, 20.25°N), over northwest Bay of Bengal, in the altitude region upto 3 km. Such high-resolution measurements of altitude profiles of aerosols are done for the first time over India. The profiles showed a near-steady vertical distribution of MB modulated with two small peaks, one at 800m and the other at ∼2000m. High resolution GPS (Global Positioning System) sonde (Vaisala) measurements around the same region onboard the research vessel Sagar Kanya (around the same time of the aircraft sortie) revealed two convectively well mixed layers, one from ground to ∼700m with an inversion at the top and the other extends from 1200m to ∼2000m with a second inversion at ∼2200m and a convectively stable region in the altitude range 700–1200m. The observed peaks in the MB profile are found to be associated with these temperature inversions. In addition, long-range transport from the Indo- Gangetic Plain (IGP) and deserts lying further to the west also influence the vertical profile of BC. Latitudinal variation of MB showed a remarkable land ocean contrast at the 500m altitude (within the well mixed region) with remarkably lower values over oceans, suggesting the impact of strong sources over the mainland. However, above the ABL (at 1500m), the latitudinal variations were quite weak, and this appears to be resulting from the impact of long-range transport. Comparison of the altitude profiles of MB over BoB off BBR with those obtained during the earlier occasion over the inland stations of Hyderabad and Kanpur showed similarities above ∼500m, with MB remaining around a steady value of ∼1 g m−3. However, large differences are seen within the ABL. Even though the observed MB values are not unusually high, their

  20. Why Are High-Altitude Natives So Strong at Altitude? Maximal Oxygen Transport to the Muscle Cell in Altitude Natives.

    Science.gov (United States)

    Lundby, Carsten; Calbet, Jose A L

    2016-01-01

    In hypoxia aerobic exercise performance of high-altitude natives is suggested to be superior to that of lowlanders; i.e., for a given altitude natives are reported to have higher maximal oxygen uptake (VO2max). The likely basis for this is a higher pulmonary diffusion capacity, which in turn ensures higher arterial O2 saturation (SaO2) and therefore also potentially a higher delivery of O2 to the exercising muscles. This review focuses on O2 transport in high-altitude Aymara. We have quantified femoral artery O2 delivery, arterial O2 extraction and calculated leg VO2 in Aymara, and compared their values with that of acclimatizing Danish lowlanders. All subjects were studied at 4100 m. At maximal exercise SaO2 dropped tremendously in the lowlanders, but did not change in the Aymara. Therefore arterial O2 content was also higher in the Aymara. At maximal exercise however, fractional O2 extraction was lower in the Aymara, and the a-vO2 difference was similar in both populations. The lower extraction levels in the Aymara were associated with lower muscle O2 conductance (a measure of muscle diffusion capacity). At any given submaximal exercise intensity, leg VO2 was always of similar magnitude in both groups, but at maximal exercise the lowlanders had higher leg blood flow, and hence also higher maximum leg VO2. With the induction of acute normoxia fractional arterial O2 extraction fell in the highlanders, but remained unchanged in the lowlanders. Hence high-altitude natives seem to be more diffusion limited at the muscle level as compared to lowlanders. In conclusion Aymara preserve very high SaO2 during hypoxic exercise (likely due to a higher lung diffusion capacity), but the effect on VO2max is reduced by a lower ability to extract O2 at the muscle level. PMID:27343089

  1. Lightweight two-stroke cycle aircraft diesel engine technology enablement program, volume 2

    Science.gov (United States)

    Freen, P. D.; Berenyi, S. G.; Brouwers, A. P.; Moynihan, M. E.

    1985-01-01

    An experimental Single Cylinder Test Engine Program is conducted to confirm the analytically projected performance of a two-stroke cycle diesel engine for aircraft applications. Testing confirms the ability of a proposed 4-cylinder version of such an engine to reach the target power at altitude in a highly turbocharged configuration. The experimental program defines all necessary parameters to permit a design of a multicylinder engine for eventual flight applications.

  2. Lightweight two-stroke cycle aircraft diesel engine technology enablement program, volume 3

    Science.gov (United States)

    Freen, P. D.; Berenyi, S. G.; Brouwers, A. P.; Moynihan, M. E.

    1985-01-01

    An experimental Single Cylinder Test Engine Program is conducted to confirm the analytically projected performance of a two-stroke cycle diesel engine for aircraft applications. Testing confirms the ability of a proposed 4-cylinder version of such an engine to reach the target power at altitude in a highly turbocharged configuration. The experimental program defines all necessary parameters to permit design of a multicylinder engine for eventual flight applications.

  3. Cross-Polar Aircraft Trajectory Optimization and the Potential Climate Impact

    Science.gov (United States)

    Ng, Hok K.; Sridhar, Banavar; Grabbe, Shon; Chen, Neil

    2011-01-01

    Cross-Polar routes offer new opportunities for air travel markets. Transpolar flights reduce travel times, fuel burns, and associated environmental emissions by flying direct paths between many North American and Asian cities. This study evaluates the potential benefits of flying wind-optimal polar routes and assessed their potential impact on climate change. An optimization algorithm is developed for transpolar flights to generate wind-optimal trajectories that minimize climate impact of aircraft, in terms of global warming potentials (relative to warming by one kg of CO2) of several types of emissions, while avoiding regions of airspace that facilitate persistent contrail formation. Estimations of global warming potential are incorporated into the objective function of the optimization algorithm to assess the climate impact of aircraft emissions discharged at a given location and altitude. The regions of airspace with very low ambient temperature and areas favorable to persistent contrail formation are modeled as undesirable regions that aircraft should avoid and are formulated as soft state constraints. The fuel burn and climate impact of cross-polar air traffic flying various types of trajectory including flight plan, great circle, wind-optimal, and contrail-avoidance are computed for 15 origin-destination pairs between major international airports in the U.S. and Asia. Wind-optimal routes reduce average fuel burn of flight plan routes by 4.4% on December 4, 2010 and 8.0% on August 7, 2010, respectively. The tradeoff between persistent contrail formation and additional global warming potential of aircraft emissions is investigated with and without altitude optimization. Without altitude optimization, the reduction in contrail travel times is gradual with increase in total fuel consumption. When altitude is optimized, a one percent increase in additional global warming potential, a climate impact equivalent to that of 4070kg and 4220kg CO2 emission, reduces 135

  4. An Evolutionary Real-Time 3D Route Planner for Aircraft

    Institute of Scientific and Technical Information of China (English)

    郑昌文; 丁明跃; 周成平

    2003-01-01

    A novel evolutionary route planner for aircraft is proposed in this paper. In the new planner, individual candidates are evaluated with respect to the workspace, thus the computation of the configuration space is not required. By using problem-specific chromosome structure and genetic operators, the routes are generated in real time,with different mission constraints such as minimum route leg length and flying altitude, maximum turning angle, maximum climbing/diving angle and route distance constraint taken into account.

  5. Radial cylinder aircraft engines

    OpenAIRE

    Šimíček, Petr

    2015-01-01

    Práce je zaměřena na konstrukční řešení letadlových hvězdicových motorů. Úvod je pojednáním o historii letadlových hvězdicových motorů a jejich vývoji v historickém kontextu. Druhá část je zaměřena na konstrukci letadlových hvězdicových motorů, následně jsou uvedena některá zajímavá konstrukční řešení a porovnání s motorem jiného druhu konstrukce. The bachelor's thesis is focused on design of aircraft radial engines. Home is a treatise on the history of aircraft radial engines and their de...

  6. Control of a swept wing tailless aircraft through wing morphing

    Science.gov (United States)

    Guiler, Richard W.

    Inspired by flight in nature, work done by Lippisch, the Hortens, and Northrop offered insight to achieving the efficiency of bird flight with swept-wing tailless aircraft. Tailless designs must incorporate aerodynamic compromises for control, which have inhibited potential advantages. A morphing mechanism, capable of changing the twist of wing and that can also provide pitch, roll and yaw control for a tailless swept wing aircraft is the first step to a series of morphing techniques, which will lead to more fluid, bird-like flight. This research focuses on investigating the design of a morphing wing to improve the flight characteristics of swept wing Horten type tailless aircraft. Free flight demonstrators, wind tunnel flow visualization, wind-tunnel force and moment data along with CFD studies have been used to evaluate the stability, control and efficiency of a morphing swept wing tailless aircraft. A wing morphing mechanism for the control of a swept wing tailless aircraft has been developed. This new control technique was experimentally and numerically compared to an existing elevon equipped tailless aircraft and has shown the potential for significant improvement in efficiency. The feasibility of this mechanism was also validated through flight testing of a flight weight version. In the process of comparing the Horten type elevon equipped aircraft and the morphing model, formal wind tunnel verification of wingtip induced thrust, found in Horten (Bell Shaped Lift distribution) type swept wing tailless aircraft was documented. A more complete physical understanding of the highly complex flow generated in the control region of the morphing tailless aircraft has been developed. CFD models indicate the possibility of the presence of a Leading Edge Vortex (LEV) on the control section morphing wing when the tip is twisted between +3.5 degrees and +7 degrees. The presence of this LEV causes a reduction of drag while lift is increased. Similar LEVs have been

  7. MISSILES AND AIRCRAFT (PART1

    Directory of Open Access Journals (Sweden)

    C.M. Meyer

    2012-02-01

    Full Text Available Many sources maintain that the role played by air power in the 1973 Yom Kippur War was important. Other interpretations state that control of air space over the battlefield areas, (either by aircraft or anti-aircraft defences, was vital.

  8. Aircraft Nuclear Propulsion Project Quarterly Progress Report for Period Ending December 31, 1956

    Energy Technology Data Exchange (ETDEWEB)

    NA, NA [ORNL

    1957-03-12

    This quarterly progress report of the Aircraft Nuclear Propulsion Project at ORNL records the technical progress of research on circulating-fuel reactors and other ANP research at the Laboratory. The report is divided into five major parts: 1) Aircraft Reactor Engineering, 2) Chemistry, and 3) Metallurgy, 4) Heat Transfer and Physical Properties, Radiation Damage, and Fuel Recovery and Reprocessing, and 5) Reactor Shielding.

  9. Measurement of OCS, CO2, CO and H2O aboard NASA's WB-57 High Altitude Platform Using Off-Axis Integrated Cavity Output Spectroscopy (OA-ICOS)

    Science.gov (United States)

    Leen, J. B.; Owano, T. G.; Du, X.; Gardner, A.; Gupta, M.

    2014-12-01

    Carbonyl sulfide (OCS) is the most abundant sulfur gas in the atmosphere and has been implicated in controlling the sulfur budget and aerosol loading of the stratosphere. In the troposphere, OCS is irreversibly consumed during photosynthesis and may serve as a tracer for gross primary production (GPP). Its primary sources are ocean outgassing, industrial processes, and biomass burning. Its primary sinks are vegetation and soils. Despite the importance of OCS in atmospheric processes, the OCS atmospheric budget is poorly determined and has high uncertainty. OCS is typically monitored using either canisters analyzed by gas chromatography or integrated atmospheric column measurements. Improved in-situ terrestrial flux and airborne measurements are required to constrain the OCS budget and further elucidate its role in stratospheric aerosol formation and as a tracer for biogenic volatile organics and photosynthesis. Los Gatos Research has developed a flight capable mid-infrared Off-Axis Integrated Cavity Output Spectroscopy (OA-ICOS) analyzer to simultaneously quantify OCS, CO2, CO, and H2O in ambient air at up to 2 Hz. The prototype was tested on diluted, certified samples and found to be precise (OCS, CO2, CO, and H2O to better than ±4 ppt, ±0.2 ppm, ±0.31 ppb, and ±3.7 ppm respectively, 1s in 1 sec) and linear (R2 > 0.9997 for all gases) over a wide dynamic range (OCS, CO2, CO, and H2O ranging from 0.2 - 70 ppb, 500 - 3000 ppm, 150 - 480 ppb, and 7000 - 21000 ppm respectively). Cross-interference measurements showed no appreciable change in measured OCS concentration with variations in CO2 (500 - 3500 ppm) or CO. We report on high altitude measurements made aboard NASA's WB-57 research aircraft. Two research flights were conducted from Houston, TX. The concentration of OCS, CO2, CO, and H2O were continuously recorded from sea level to approximately 60,000 feet. The concentration of OCS was observed to increase with altitude through the troposphere due to the

  10. [Effect of altitude on iron absorption].

    Science.gov (United States)

    Pizarro, F; Zavaleta, N; Hertrampf, E; Berlanga, R; Camborda, L; Olivares, M

    1998-03-01

    Iron bioavailability was evaluated in people living in high altitudes. Absorption was estimated from a reference dose of ferrous ascorbate and from a standard diet of wheat flour, using extrinsic tag radioisotope technique of 55Fe and 59Fe. Twenty four volunteers, healthy women, with ages ranging from 28 to 45 years, participated. Of those, eleven lived at 3450 meters above sea level (m.a.s.l.) in Huancayo city-Peru (study group), and 13 lived in Santiago de Chile at 630 m.a.s.l. (control group). Iron absorption from reference dose of ferrous ascorbate was 32.0% and 31.1% in the study and control groups respectively. The geometric mean of iron absorption from the standard diet, corrected to 40% of absorption of reference dose, was 9.0% and 6.9% in the study and control groups respectively (NS). The results suggest that altitude does not produce a high iron absorption in highlander residents.

  11. Dust observations at orbital altitudes surrounding Mars.

    Science.gov (United States)

    Andersson, L; Weber, T D; Malaspina, D; Crary, F; Ergun, R E; Delory, G T; Fowler, C M; Morooka, M W; McEnulty, T; Eriksson, A I; Andrews, D J; Horanyi, M; Collette, A; Yelle, R; Jakosky, B M

    2015-11-01

    Dust is common close to the martian surface, but no known process can lift appreciable concentrations of particles to altitudes above ~150 kilometers. We present observations of dust at altitudes ranging from 150 to above 1000 kilometers by the Langmuir Probe and Wave instrument on the Mars Atmosphere and Volatile Evolution spacecraft. Based on its distribution, we interpret this dust to be interplanetary in origin. A comparison with laboratory measurements indicates that the dust grain size ranges from 1 to 12 micrometers, assuming a typical grain velocity of ~18 kilometers per second. These direct observations of dust entering the martian atmosphere improve our understanding of the sources, sinks, and transport of interplanetary dust throughout the inner solar system and the associated impacts on Mars's atmosphere.

  12. Dust observations at orbital altitudes surrounding Mars.

    Science.gov (United States)

    Andersson, L; Weber, T D; Malaspina, D; Crary, F; Ergun, R E; Delory, G T; Fowler, C M; Morooka, M W; McEnulty, T; Eriksson, A I; Andrews, D J; Horanyi, M; Collette, A; Yelle, R; Jakosky, B M

    2015-11-01

    Dust is common close to the martian surface, but no known process can lift appreciable concentrations of particles to altitudes above ~150 kilometers. We present observations of dust at altitudes ranging from 150 to above 1000 kilometers by the Langmuir Probe and Wave instrument on the Mars Atmosphere and Volatile Evolution spacecraft. Based on its distribution, we interpret this dust to be interplanetary in origin. A comparison with laboratory measurements indicates that the dust grain size ranges from 1 to 12 micrometers, assuming a typical grain velocity of ~18 kilometers per second. These direct observations of dust entering the martian atmosphere improve our understanding of the sources, sinks, and transport of interplanetary dust throughout the inner solar system and the associated impacts on Mars's atmosphere. PMID:26542578

  13. Dust observations at orbital altitudes surrounding Mars

    Science.gov (United States)

    Andersson, L.; Weber, T. D.; Malaspina, D.; Crary, F.; Ergun, R. E.; Delory, G. T.; Fowler, C. M.; Morooka, M. W.; McEnulty, T.; Eriksson, A. I.; Andrews, D. J.; Horanyi, M.; Collette, A.; Yelle, R.; Jakosky, B. M.

    2015-11-01

    Dust is common close to the martian surface, but no known process can lift appreciable concentrations of particles to altitudes above ~150 kilometers. We present observations of dust at altitudes ranging from 150 to above 1000 kilometers by the Langmuir Probe and Wave instrument on the Mars Atmosphere and Volatile Evolution spacecraft. Based on its distribution, we interpret this dust to be interplanetary in origin. A comparison with laboratory measurements indicates that the dust grain size ranges from 1 to 12 micrometers, assuming a typical grain velocity of ~18 kilometers per second. These direct observations of dust entering the martian atmosphere improve our understanding of the sources, sinks, and transport of interplanetary dust throughout the inner solar system and the associated impacts on Mars’s atmosphere.

  14. Predator foraging altitudes reveal the structure of aerial insect communities

    OpenAIRE

    Helms, Jackson A.; Aaron P. Godfrey; Tayna Ames; Bridge, Eli S.

    2016-01-01

    The atmosphere is populated by a diverse array of dispersing insects and their predators. We studied aerial insect communities by tracking the foraging altitudes of an avian insectivore, the Purple Martin (Progne subis). By attaching altitude loggers to nesting Purple Martins and collecting prey delivered to their nestlings, we determined the flight altitudes of ants and other insects. We then tested hypotheses relating ant body size and reproductive ecology to flight altitude. Purple Martins...

  15. Pulmonary embolism in young natives of high altitude

    Directory of Open Access Journals (Sweden)

    Sanjay Singhal

    2016-01-01

    Full Text Available Thrombotic events are relatively common in high altitude areas and known to occur in young soldiers working at high altitude without usual risk factors associated with thrombosis at sea-level. However, till now, cases with thrombotic events were reported only in lowlanders staying at high altitude. These two cases of pulmonary embolism demonstrate that thrombotic events can occur in highlanders after a prolonged stay at the extreme altitude.

  16. Enabling Use of Unmanned Aircraft Systems for Arctic Environmental Monitoring

    DEFF Research Database (Denmark)

    Storvold, Rune; la Cour-Harbo, Anders; Mulac, Brenda;

    , satellites and manned aircraft are the traditional platforms on which scientists gather data of the atmosphere, sea ice, glaciers, fauna and vegetation. However, significant data gaps still exist over much of the Arctic because there are few research stations, satellites are often hindered by cloud cover......, poor resolution, and the complicated surface of snow and ice. Measurements made from manned aircraft are also limited because of range and endurance, as well as the danger and costs presented by operating manned aircraft in harsh and remote environments like the Arctic. Unmanned aircraft systems (UAS......, technical and logistical challenges facing scientists intending to use UAS in their arctic work. Future planned campaigns and science goals under the Coordinated Investigation of Climate-Cryosphere Interactions (CICCI) umbrella will be outlined. A new AMAP report on conducting safe UAS operations...

  17. An economic model for evaluating high-speed aircraft designs

    Science.gov (United States)

    Vandervelden, Alexander J. M.

    1989-01-01

    A Class 1 method for determining whether further development of a new aircraft design is desirable from all viewpoints is presented. For the manufacturer the model gives an estimate of the total cost of research and development from the preliminary design to the first production aircraft. Using Wright's law of production, one can derive the average cost per aircraft produced for a given break-even number. The model will also provide the airline with a good estimate of the direct and indirect operating costs. From the viewpoint of the passenger, the model proposes a tradeoff between ticket price and cruise speed. Finally all of these viewpoints are combined in a Comparative Aircraft Seat-kilometer Economic Index.

  18. Neutral Barium Cloud Evolution at Different Altitudes

    Institute of Scientific and Technical Information of China (English)

    李磊; 徐荣栏

    2002-01-01

    Considering the joint effects of diffusion, collision, oxidation and photoionization, we study the evolution of the barium cloud at different altitudes in the space plasma active experiment. The results present the variation of the loss rate, number density distribution and brightness of the barium cloud over the range from 120 to 260km.This can be divided into oxidation, oxidation plus photoionization and photoionization regions.

  19. Cardiovascular Response to High Altitude Hypoxia

    OpenAIRE

    Manchanda, S C

    1984-01-01

    Normal and abnormal cardiovascular response to high altitude (HA) hypoxia were studied in 98 healthy subjects and in 15 patients with HA pulmonary oedema (HAPO) and acute mountain sickness (AMS) at an altitudeof 3,658 m. The healthy sea level (SL) residents showed marked blood volume changes during the first week with pulmonary hypotension and depression of left ventricular (LV) performance and physical work capacity (PWC). The HA natives, however, had better LV performance and PWC indicating...

  20. Commercial Aircraft Integrated Vehicle Health Management Study

    Science.gov (United States)

    Reveley, Mary S.; Briggs, Jeffrey L.; Evans, Joni K.; Jones, Sharon Monica; Kurtoglu, Tolga; Leone, Karen M.; Sandifer, Carl E.; Thomas, Megan A.

    2010-01-01

    Statistical data and literature from academia, industry, and other government agencies were reviewed and analyzed to establish requirements for fixture work in detection, diagnosis, prognosis, and mitigation for IVHM related hardware and software. Around 15 to 20 percent of commercial aircraft accidents between 1988 and 2003 involved inalftfnctions or failures of some aircraft system or component. Engine and landing gear failures/malfunctions dominate both accidents and incidents. The IVI vl Project research technologies were found to map to the Joint Planning and Development Office's National Research and Development Plan (RDP) as well as the Safety Working Group's National Aviation Safety Strategic. Plan (NASSP). Future directions in Aviation Technology as related to IVHlvl were identified by reviewing papers from three conferences across a five year time span. A total of twenty-one trend groups in propulsion, aeronautics and aircraft categories were compiled. Current and ftiture directions of IVHM related technologies were gathered and classified according to eight categories: measurement and inspection, sensors, sensor management, detection, component and subsystem monitoring, diagnosis, prognosis, and mitigation.

  1. Scientific Infrastructure To Support Manned And Unmanned Aircraft, Tethered Balloons, And Related Aerial Activities At Doe Arm Facilities On The North Slope Of Alaska

    Science.gov (United States)

    Ivey, M.; Dexheimer, D.; Hardesty, J.; Lucero, D. A.; Helsel, F.

    2015-12-01

    The U.S. Department of Energy (DOE), through its scientific user facility, the Atmospheric Radiation Measurement (ARM) facilities, provides scientific infrastructure and data to the international Arctic research community via its research sites located on the North Slope of Alaska. DOE has recently invested in improvements to facilities and infrastructure to support operations of unmanned aerial systems for science missions in the Arctic and North Slope of Alaska. A new ground facility, the Third ARM Mobile Facility, was installed at Oliktok Point Alaska in 2013. Tethered instrumented balloons were used to make measurements of clouds in the boundary layer including mixed-phase clouds. A new Special Use Airspace was granted to DOE in 2015 to support science missions in international airspace in the Arctic. Warning Area W-220 is managed by Sandia National Laboratories for DOE Office of Science/BER. W-220 was successfully used for the first time in July 2015 in conjunction with Restricted Area R-2204 and a connecting Altitude Reservation Corridor (ALTRV) to permit unmanned aircraft to operate north of Oliktok Point. Small unmanned aircraft (DataHawks) and tethered balloons were flown at Oliktok during the summer and fall of 2015. This poster will discuss how principal investigators may apply for use of these Special Use Airspaces, acquire data from the Third ARM Mobile Facility, or bring their own instrumentation for deployment at Oliktok Point, Alaska. The printed poster will include the standard DOE funding statement.

  2. Central Sleep Apnea at High Altitude.

    Science.gov (United States)

    Burgess, Keith R; Ainslie, Philip N

    2016-01-01

    The discovery of central sleep apnea (CSA) at high altitude is usually attributed to Angelo Mosso who published in 1898. It can occur in susceptible individuals at altitude above 2000 m, but at very high altitude, say above 5000 m, it will occur in most subjects. Severity is correlated with ventilatory responsiveness, particularly to hypoxia. Theoretically, it should spontaneously improve with time and acclimatization. Although the time course of resolution is not well described, it appears to persist for more than a month at 5000 m.It occurs due to the interaction of hypocapnia with stages 1 and 2 NREM sleep, in the presence of increased loop-gain. The hypocapnia is secondary to hypoxic ventilatory drive. With acclimatization, one might expect that the increase in PaO2 and cerebral blood flow (CBF) would mitigate the CSA. However, over time, both the hypoxic and hypercapnic ventilatory responses increase, causing an increase in loop gain which is a counteracting force.The severity of the CSA can be reduced by descent, supplemental oxygen therapy, oral or intravenous acetazolamide. Recent studies suggest that acute further increases in cerebral blood flow will substantially, but temporarily, reduce central sleep apnea, without altering acid based balance. Very recently, bi-level noninvasive ventilation has also been shown to help (mechanism unknown). Sleep quality can be improved independent of the presence of CSA by the use of benzodiazepine sedation. PMID:27343103

  3. The effect of altitude hypoxia on glucose homeostasis in men

    DEFF Research Database (Denmark)

    Larsen, J J; Hansen, J M; Olsen, Niels Vidiendal;

    1997-01-01

    1. Exposure to altitude hypoxia elicits changes in glucose homeostasis with increases in glucose and insulin concentrations within the first few days at altitude. Both increased and unchanged hepatic glucose production (HGP) have previously been reported in response to acute altitude hypoxia...

  4. Nutritional Aspects of High Altitude and Snow Bound Areas

    OpenAIRE

    K. Sridharan; R. M. Rai

    1984-01-01

    The precise nutritional requirement of humans at high altitude area is not well defined. Further there are many conflicting reports on the effects of hypoxia on digestion, absorption and utilization of food at high altitude. In this review the nutritional requirements at high altitude and the effects of hypoxia on humans in relation to nutrition have been discussed.

  5. Nutritional Aspects of High Altitude and Snow Bound Areas

    Directory of Open Access Journals (Sweden)

    K. Sridharan

    1984-10-01

    Full Text Available The precise nutritional requirement of humans at high altitude area is not well defined. Further there are many conflicting reports on the effects of hypoxia on digestion, absorption and utilization of food at high altitude. In this review the nutritional requirements at high altitude and the effects of hypoxia on humans in relation to nutrition have been discussed.

  6. Intelligent control of agile aircraft

    Energy Technology Data Exchange (ETDEWEB)

    Mohler, R.R.; Zakrzewski, R.R. [Dept. of Electrical and Computer Engineering, Corvallis, OR (United States)

    1994-12-31

    A brief overview of adaptive and computer-aided flight control is presented as background for the evolution of recent research on nonlinear intelligent control. Here, several nonlinear control algorithms are investigated but emphasis is given to nearly time-optimal, neural-net generated feedback control which is trained on ideal minimum-time, open-loop trajectories. The minimum-time policies are computed by a new version of the switching-line-variational method (gradient algorithm). Critical control constraints and a benchmark for performance as well as a basis for training are obtained for the system design. This further demonstrates the need for an integrated controls and aircraft system design for full utilization of nonlinear control capability. Complex nonlinear simulations show the effectiveness of the derived nonlinear feedback controller for the high-angle-of-attack research vehicle (HARV) with stabilator and thrust-vector control. For example, angle of attack is controlled from near zero to sixty degrees in about two seconds with appropriate trim conditions at both ends. Such control greatly enhances maneuverability and general flight envelope admissibility.

  7. Origin of ozone and NO x in the tropical troposphere: A photochemical analysis of aircraft observations over the South Atlantic basin

    OpenAIRE

    Jacob, Daniel James; Heikes, E. G.; Fan, S.-M.; Logan, Jennifer A.; Mauzerall, D. L.; Bradshaw, J. D.; Singh, H.B.; Gregory, G. L.; R. W. Talbot; D. R. Blake; Sachse, G. W.

    1996-01-01

    The photochemistry of the troposphere over the South Atlantic basin is examined by modeling of aircraft observations up to 12-km altitude taken during the TRACE A expedition in September–October 1992. A close balance is found in the 0 to 12-km column between photochemical production and loss of O3, with net production at high altitudes compensating for weak net loss at low altitudes. This balance implies that O3 concentrations in the 0–12 km column can be explained solely by in situ photochem...

  8. Macroscopic time and altitude distribution of plasma turbulence induced in ionospheric modification experiments

    Energy Technology Data Exchange (ETDEWEB)

    Rose, H.; Dubois, D.; Russell, D. [Lodestar Research Corp., Boulder, CO (United States); Hanssen, A. [Univ. of Tromsoe (Norway)

    1996-03-01

    This is the final report of a three-year Laboratory-Directed Research and Development (LDRD) project at the Los Alamos National Laboratory (LANL). This research concentrated on the time dependence of the heater, induced-turbulence, and electron-density profiles excited in the ionosphere by a powerful radio-frequency heater wave. The macroscopic density is driven by the ponderomotive pressure and the density self-consistently determines the heater propagation. For typical parameters of the current Arecibo heater, a dramatic quasi-periodic behavior was found. For about 50 ms after turn-on of the heater wave, the turbulence is concentrated at the first standing-wave maximum of the heater near reflection altitude. From 50--100 ms the standing-wave pattern drops by about 1--2 km in altitude and the quasi-periodicity reappears at the higher altitudes with a period of roughly 50 ms. This behavior is due to the half-wavelength density depletion grating that is set up by the ponderomotive pressure at the maxima of the heater standing-wave pattern. Once the grating is established the heater can no longer propagate to higher altitudes. The grating is then unsupported by the heater at these altitudes and decays, allowing the heater to propagate again and initiate another cycle. For stronger heater powers, corresponding to the Arecibo upgrade and the HAARP heater now under construction, the effects are much more dramatic.

  9. Macroscopic time and altitude distribution of plasma turbulence induced in ionospheric modification experiments

    International Nuclear Information System (INIS)

    This is the final report of a three-year Laboratory-Directed Research and Development (LDRD) project at the Los Alamos National Laboratory (LANL). This research concentrated on the time dependence of the heater, induced-turbulence, and electron-density profiles excited in the ionosphere by a powerful radio-frequency heater wave. The macroscopic density is driven by the ponderomotive pressure and the density self-consistently determines the heater propagation. For typical parameters of the current Arecibo heater, a dramatic quasi-periodic behavior was found. For about 50 ms after turn-on of the heater wave, the turbulence is concentrated at the first standing-wave maximum of the heater near reflection altitude. From 50--100 ms the standing-wave pattern drops by about 1--2 km in altitude and the quasi-periodicity reappears at the higher altitudes with a period of roughly 50 ms. This behavior is due to the half-wavelength density depletion grating that is set up by the ponderomotive pressure at the maxima of the heater standing-wave pattern. Once the grating is established the heater can no longer propagate to higher altitudes. The grating is then unsupported by the heater at these altitudes and decays, allowing the heater to propagate again and initiate another cycle. For stronger heater powers, corresponding to the Arecibo upgrade and the HAARP heater now under construction, the effects are much more dramatic

  10. Examining the Relationship Between Passenger Airline Aircraft Maintenance Outsourcing and Aircraft Safety

    Science.gov (United States)

    Monaghan, Kari L.

    The problem addressed was the concern for aircraft safety rates as they relate to the rate of maintenance outsourcing. Data gathered from 14 passenger airlines: AirTran, Alaska, America West, American, Continental, Delta, Frontier, Hawaiian, JetBlue, Midwest, Northwest, Southwest, United, and USAir covered the years 1996 through 2008. A quantitative correlational design, utilizing Pearson's correlation coefficient, and the coefficient of determination were used in the present study to measure the correlation between variables. Elements of passenger airline aircraft maintenance outsourcing and aircraft accidents, incidents, and pilot deviations within domestic passenger airline operations were analyzed, examined, and evaluated. Rates of maintenance outsourcing were analyzed to determine the association with accident, incident, and pilot deviation rates. Maintenance outsourcing rates used in the evaluation were the yearly dollar expenditure of passenger airlines for aircraft maintenance outsourcing as they relate to the total airline aircraft maintenance expenditures. Aircraft accident, incident, and pilot deviation rates used in the evaluation were the yearly number of accidents, incidents, and pilot deviations per miles flown. The Pearson r-values were calculated to measure the linear relationship strength between the variables. There were no statistically significant correlation findings for accidents, r(174)=0.065, p=0.393, and incidents, r(174)=0.020, p=0.793. However, there was a statistically significant correlation for pilot deviation rates, r(174)=0.204, p=0.007 thus indicating a statistically significant correlation between maintenance outsourcing rates and pilot deviation rates. The calculated R square value of 0.042 represents the variance that can be accounted for in aircraft pilot deviation rates by examining the variance in aircraft maintenance outsourcing rates; accordingly, 95.8% of the variance is unexplained. Suggestions for future research include

  11. Rationale and operational plan for a U.S. high-altitude magnetic survey

    Science.gov (United States)

    Hildenbrand, Thomas G.; Acuna, Mario; Bracken, Robert E.; Hardwick, Doug; Hinze, William J.; Keller, Gordon R.; Phillips, Jeff; Roest, Walter

    2002-01-01

    On August 8, 2002, twenty-one scientists from the federal, private and academic sectors met at a workshop in Denver, Co., to discuss the feasibility of collecting magnetic anomaly data on a Canberra aircraft (Figure 1). The need for this 1-day workshop arose because of an exciting and cost-effective opportunity to collect invaluable magnetic anomaly data during a Canberra mission over the U.S. in 2003 and 2004. High Altitude Mapping Missions (HAMM) is currently planning a mission to collect Interferometric Synthetic Aperture Radar (IFSAR) imagery at an altitude of about 15 km and with a flight-line spacing of about 18 km over the conterminous U.S. and Alaska. The additional collection of total and vector magnetic field data would represent a secondary mission objective (i.e., a "piggy-back" magnetometer system). Because HAMM would fund the main flight costs of the mission, the geomagnetic community would obtain invaluable magnetic data at a nominal cost. These unique data would provide new insights on fundamental tectonic and thermal processes and give a new view of the structural and lithologic framework of the crust and possibly the upper mantle. This document highlights: (1) the reasons to conduct this national survey and (2) a preliminary operational plan to collect high-altitude magnetic data of a desired quality and for the expected resources. Although some operational plan issues remain to be resolved, the important conclusions of the workshop are that the Canberra is a very suitable platform to measure the magnetic field and that the planned mission will result in quality high-altitude magnetic data to greatly expand the utility of our national magnetic database.

  12. Terahertz-based relative positioning of aircraft flying in formation

    Science.gov (United States)

    Parker, John Scott

    This thesis introduces a new method for estimating the relative positions of aircraft flying in formation using terahertz frequency (THz) signals. We look specifically at the military precision airdrop application, where THz signals have two advantages: (1) stealth due to preferential propagation in the horizontal direction at high altitudes and (2) robustness for operations in GPS-denied environments. This thesis presents two system concepts for implementation. The first, dubbed the straight-and-level (SAL) architecture, produces high precision position estimates during straight and level flight, but suffers from systematic biases when the receiving aircraft performs a maneuver. In support of this architecture, we published the first ever paper on THz relative positioning, and introduced a new filtering method inspired by the well-known GPS Hatch Filter. The second, dubbed the refined-for-maneuvers (RFM) architecture, produces position estimates that are less precise than the SAL architecture, but have no systematic bias when the aircraft maneuver. Simulations are used to predict the performance of the architectures.

  13. Aircraft radar antennas

    Science.gov (United States)

    Schrank, Helmut E.

    1987-04-01

    Many changes have taken place in airborne radar antennas since their beginnings over forty years ago. A brief historical review of the advances in technology is presented, from mechanically scanned reflectors to modern multiple function phased arrays. However, emphasis is not on history but on the state-of-the-art technology and trends for future airborne radar systems. The status of rotating surveillance antennas is illustrated by the AN/APY-1 Airborne Warning and Control System (AWACS) slotted waveguide array, which achieved a significant breakthrough in sidelobe suppression. Gimballed flat plate arrays in nose radomes are typified by the AN/APG-66 (F-16) antenna. Multifunction phased arrays are presented by the Electronically Agile Radar (EAR) antenna, which has achieved significant advances in performance versatility and reliability. Trends toward active aperture, adaptive, and digital beamforming arrays are briefly discussed. Antennas for future aircraft radar systems must provide multiple functions in less aperture space, and must perform more reliably.

  14. Commercial aircraft composite technology

    CERN Document Server

    Breuer, Ulf Paul

    2016-01-01

    This book is based on lectures held at the faculty of mechanical engineering at the Technical University of Kaiserslautern. The focus is on the central theme of societies overall aircraft requirements to specific material requirements and highlights the most important advantages and challenges of carbon fiber reinforced plastics (CFRP) compared to conventional materials. As it is fundamental to decide on the right material at the right place early on the main activities and milestones of the development and certification process and the systematic of defining clear requirements are discussed. The process of material qualification - verifying material requirements is explained in detail. All state-of-the-art composite manufacturing technologies are described, including changes and complemented by examples, and their improvement potential for future applications is discussed. Tangible case studies of high lift and wing structures emphasize the specific advantages and challenges of composite technology. Finally,...

  15. High Altitude Aerial Natural Gas Leak Detection System

    Energy Technology Data Exchange (ETDEWEB)

    Richard T. Wainner; Mickey B. Frish; B. David Green; Matthew C. Laderer; Mark G. Allen; Joseph R. Morency

    2006-12-31

    The objective of this program was to develop and demonstrate a cost-effective and power-efficient advanced standoff sensing technology able to detect and quantify, from a high-altitude (> 10,000 ft) aircraft, natural gas leaking from a high-pressure pipeline. The advanced technology is based on an enhanced version of the Remote Methane Leak Detector (RMLD) platform developed previously by Physical Sciences Inc. (PSI). The RMLD combines a telecommunications-style diode laser, fiber-optic components, and low-cost DSP electronics with the well-understood principles of Wavelength Modulation Spectroscopy (WMS), to indicate the presence of natural gas located between the operator and a topographic target. The transceiver transmits a laser beam onto a topographic target and receives some of the laser light reflected by the target. The controller processes the received light signal to deduce the amount of methane in the laser's path. For use in the airborne platform, we modified three aspects of the RMLD, by: (1) inserting an Erbium-doped optical fiber laser amplifier to increase the transmitted laser power from 10 mW to 5W; (2) increasing the optical receiver diameter from 10 cm to 25 cm; and (3) altering the laser wavelength from 1653 nm to 1618 nm. The modified RMLD system provides a path-integrated methane concentration sensitivity {approx}5000 ppm-m, sufficient to detect the presence of a leak from a high capacity transmission line while discriminating against attenuation by ambient methane. In ground-based simulations of the aerial leak detection scenario, we demonstrated the ability to measure methane leaks within the laser beam path when it illuminates a topographic target 2000 m away. We also demonstrated simulated leak detection from ranges of 200 m using the 25 cm optical receiver without the fiber amplifier.

  16. Aircraft exhaust aerosol formation and growth

    Energy Technology Data Exchange (ETDEWEB)

    Brown, R.C.; Miake-Lye, R.C.; Anderson, M.R.; Kolb, C.E. [Aerodyne Research, Inc., Billerica, MA (United States). Center for Chemical and Environmental Physics

    1997-12-31

    Aerosol formation and growth in the exhaust plume of the ATTAS aircraft at an altitude of approximately 9 km, burning fuels with 2 ppmm sulfur (`low`) and 266 ppmm (`high`) sulfur has been modeled using an aerosol dynamics model for nucleation, vapor condensation and coagulation, coupled to a 2-dimensional, axisymmetric flow code to treat plume dilution and turbulent mixing. For both the `low` and `high` sulfur fuels, approximately 60% of the available water had condensed within the first 200 m downstream of the exhaust exit. The contrail particle diameters ranged between 0.4 to 1.6 {mu}m. However, the size distributions as a function of radial position for the `low` sulfur plume were broader than the corresponding distributions for the `high` sulfur plume. The model results indicate for a fuel sulfur mass loading of 2 ppmm, sulfuric acid remains a viable activating agent and that the differences in the contrail particle size distributions for sulfur mass loadings between 2 ppmm and 260 ppmm would be difficult to detect. (author) 12 refs.

  17. Aircraft landing gear extension and retraction control system diagnostics, prognostics and health management

    OpenAIRE

    Yang, Yang

    2012-01-01

    This thesis contains the Group Design Project (GDP) work and Individual Research Project (IRP) work. The target of this GDP was to design a long range flying wing passenger aircraft to meet the increasing global aircraft demand. The name of this flying wing aircraft is FW-11. This is a project cooperated between Aviation Industry Corporation of China (AVIC) and Cranfield University. The writer was involved in the conceptual design stage of this project. The author was in cha...

  18. The passive and active noise control strategy in the aircraft interior noise

    OpenAIRE

    Paonessa, A.

    1994-01-01

    The stringent comfort requirements that the airliners are providing to the aircraft manufacturers, also for the small regional commuter are increasing the attention of the aircraft designer to the aircraft interior noise performance. The research on the design methodologies is very much improved in the last years providing new materials and new system like the active noise control usefull to get a more comfortable interior and achieve a large competition on the market. In this paper a general...

  19. Special Issue: Adaptive/Smart Structures and Multifunctional Materials with Application to Morphing Aircraft

    Directory of Open Access Journals (Sweden)

    Rafic Ajaj

    2014-12-01

    Full Text Available Recent advances in smart structures and multifunctional materials have facilitated many novel aerospace technologies such as morphing aircraft. A morphing aircraft, bio-inspired by natural fliers, has gained a lot of interest as a potential technology to meet the ambitious goals of the Advisory Council for Aeronautics Research in Europe (ACARE Vision 2020 and the FlightPath 2050 documents. A morphing aircraft continuously adjusts its wing geometry to enhance flight performance, control authority, and multi-mission capability.[...

  20. Alternative aircraft anti-icing formulations with reduced aquatic toxicity and biochemical oxygen demand

    Science.gov (United States)

    Gold, Harris; Joback, Kevin; Geis, Steven; Bowman, George; Mericas, Dean; Corsi, Steven R.; Ferguson, Lee

    2010-01-01

    The current research was conducted to identify alternative aircraft and pavement deicer and anti-icer formulations with improved environmental characteristics compared to currently used commercial products (2007). The environmental characteristics of primary concern are the biochemical oxygen demand (BOD) and aquatic toxicity of the fully formulated products. Except when the distinction among products is necessary for clarity, “deicer” will refer to aircraft-deicing fluids (ADFs), aircraft anti-icing fluids (AAFs), and pavementdeicing materials (PDMs).