Holmes, Bruce J.; Durham, Michael H.; Tarry, Scott E.
This paper summarizes both the vision and the early public-private collaborative research for the Small Aircraft Transportation System (SATS). The paper outlines an operational definition of SATS, describes how SATS conceptually differs from current air transportation capabilities, introduces four SATS operating capabilities, and explains the relation between the SATS operating capabilities and the potential for expanded air mobility. The SATS technology roadmap encompasses on-demand, widely distributed, point-to-point air mobility, through hired-pilot modes in the nearer-term, and through self-operated user modes in the farther-term. The nearer-term concept is based on aircraft and airspace technologies being developed to make the use of smaller, more widely distributed community reliever and general aviation airports and their runways more useful in more weather conditions, in commercial hired-pilot service modes. The farther-term vision is based on technical concepts that could be developed to simplify or automate many of the operational functions in the aircraft and the airspace for meeting future public transportation needs, in personally operated modes. NASA technology strategies form a roadmap between the nearer-term concept and the farther-term vision. This paper outlines a roadmap for scalable, on-demand, distributed air mobility technologies for vehicle and airspace systems. The audiences for the paper include General Aviation manufacturers, small aircraft transportation service providers, the flight training industry, airport and transportation authorities at the Federal, state and local levels, and organizations involved in planning for future National Airspace System advancements.
Abbott, Terence S.; Consiglio, Maria C.; Baxley, Brian T.; Williams, Daniel M.; Jones, Kenneth M.; Adams, Catherine A.
This document defines the Small Aircraft Transportation System (SATS) Higher Volume Operations concept. The general philosophy underlying this concept is the establishment of a newly defined area of flight operations called a Self-Controlled Area (SCA). Within the SCA, pilots would take responsibility for separation assurance between their aircraft and other similarly equipped aircraft. This document also provides details for a number of off-nominal and emergency procedures which address situations that could be expected to occur in a future SCA. The details for this operational concept along with a description of candidate aircraft systems to support this concept are provided.
Jabbal, M; Liddle, SC; Crowther, WJ
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...
Full Text Available The algorithm of unconditional and conditional optimization Markov models of maintenance systems of transport airplanes of their programs of technical operation used at improvement is considered.
Kemmerly, Guy T.
To all peoples in all parts of the world throughout history, the ability to move about easily is a fundamental element of freedom. The American people have charged NASA to increase their freedom and that of their children knowing that their quality of life will improve as our nation s transportation systems improve. In pursuit of this safe, reliable, and affordable personalized air transportation option, in 2000 NASA established the Small Aircraft Transportation System (SATS) Project. As the name suggests personalized air transportation would be built on smaller aircraft than those used by the airlines. Of course, smaller aircraft can operate from smaller airports and 96% of the American population is within thirty miles of a high-quality, underutilized community airport as are the vast majority of their customers, family members, and favorite vacation destinations.
Abbott, Terence S.; Jones, Kenneth M.; Consiglio, Maria C.; Williams, Daniel M.; Adams, Catherine A.
This document defines the Small Aircraft Transportation System (SATS), Higher Volume Operations (HVO) concept for normal conditions. In this concept, a block of airspace would be established around designated non-towered, non-radar airports during periods of poor weather. Within this new airspace, pilots would take responsibility for separation assurance between their aircraft and other similarly equipped aircraft. Using onboard equipment and procedures, they would then approach and land at the airport. Departures would be handled in a similar fashion. The details for this operational concept are provided in this document.
Airworthiness certification of commercial transport aircraft requires a safety analysis of the propulsion system to establish that the probability of a failure jeopardising the safety of the aeroplane is acceptably low. The needs and desired features of such a propulsion system safety analysis are discussed, and current techniques and assumptions employed in such analyses are evaluated. It is concluded that current assumptions and techniques are not well suited to predicting...
Stough, H. Paul, III
Atmospheric effects on aviation are described by Mahapatra (1999) as including (1) atmospheric phenomena involving air motion - wind shear and turbulence; (2) hydrometeorological phenomena - rain, snow and hail; (3) aircraft icing; (4) low visibility; and (5) atmospheric electrical phenomena. Aircraft Weather Mitigation includes aircraft systems (e.g. airframe, propulsion, avionics, controls) that can be enacted (by a pilot, automation or hybrid systems) to suppress and/or prepare for the effects of encountered or unavoidable weather or to facilitate a crew operational decision-making process relative to weather. Aircraft weather mitigation can be thought of as a continuum (Figure 1) with the need to avoid all adverse weather at one extreme and the ability to safely operate in all weather conditions at the other extreme. Realistic aircraft capabilities fall somewhere between these two extremes. The capabilities of small general aviation aircraft would be expected to fall closer to the "Avoid All Adverse Weather" point, and the capabilities of large commercial jet transports would fall closer to the "Operate in All Weather Conditions" point. The ability to safely operate in adverse weather conditions is dependent upon the pilot s capabilities (training, total experience and recent experience), the airspace in which the operation is taking place (terrain, navigational aids, traffic separation), the capabilities of the airport (approach guidance, runway and taxiway lighting, availability of air traffic control), as well as the capabilities of the airplane. The level of mitigation may vary depending upon the type of adverse weather. For example, a small general aviation airplane may be equipped to operate "in the clouds" without outside visual references, but not be equipped to prevent airframe ice that could be accreted in those clouds.
Rising, J. J.; Davis, W. J; Grantham, W. D.
The use of modern control theory to develop a high-authority stability and control system for the next generation transport aircraft is described with examples taken from work performed on an advanced pitch active control system (PACS). The PACS was configured to have short-period and phugoid modes frequency and damping characteristics within the shaded S-plane areas, column force gradients with set bounds and with constant slope, and a blended normal-acceleration/pitch rate time history response to a step command. Details of the control law, feedback loop, and modal control syntheses are explored, as are compensation for the feedback gain, the deletion of the velocity signal, and the feed-forward compensation. Scheduling of the primary and secondary gains are discussed, together with control law mechanization, flying qualities analyses, and application on the L-1011 aircraft.
N. Shantha Kumar
Full Text Available A new avionics concept called integrated enhanced and synthetic vision system (IESVS is being developed to enable flight operations during adverse weather/visibility conditions even in non precision airfields. This paper presents the latest trends in IESVS, design concept of the system and the work being carried out at National Aerospace Laboratories, Bangalore towards indigenous development of the same for transport aircraft.Defence Science Journal, 2013, 63(2, pp.157-163, DOI:http://dx.doi.org/10.14429/dsj.63.4258
Dollyhigh, Samuel M.; Yackovetsky, Robert E. (Technical Monitor)
An analysis was conducted to examine the market viability of small aircraft as a transportation mode in competition with automobile and scheduled commercial air travel by estimating the pool of users that would potentially switch to on-demand air travel due to cost/time savings. The basis for the analysis model was the Integrated Air Transportation System Evaluation Tool (IATSET) which was developed under contract to NASA by the Logistics Management Institute. IATSET is a macroeconomic model that predicts at a National level the mode choice between automobile, scheduled air, and on-demand air travel based on the value of a travelers time and monetary cost of the trip. A number of modifications are detailed to the original IATSET to better model the changing small aircraft environment. The potential trip market was modeled for the Eclipse 500 operated as a corporate jet and as an air taxi for the business travel market. The Cirrus 20R and a $80K single engine piston aircraft (based on automobile manufacturing technology) are evaluated in the pleasure and personal business travel market.
Long, Dou; Lee, David; Johnson, Jesse; Kostiuk, Peter; Yackovetsky, Robert (Technical Monitor)
The Small Aircraft Transportation System (SATS) demand modeling is a tool that will be useful for decision-makers to analyze SATS demands in both airport and airspace. We constructed a series of models following the general top-down, modular principles in systems engineering. There are three principal models, SATS Airport Demand Model (SATS-ADM), SATS Flight Demand Model (SATS-FDM), and LMINET-SATS. SATS-ADM models SATS operations, by aircraft type, from the forecasts in fleet, configuration and performance, utilization, and traffic mixture. Given the SATS airport operations such as the ones generated by SATS-ADM, SATS-FDM constructs the SATS origin and destination (O&D) traffic flow based on the solution of the gravity model, from which it then generates SATS flights using the Monte Carlo simulation based on the departure time-of-day profile. LMINET-SATS, an extension of LMINET, models SATS demands at airspace and airport by all aircraft operations in US The models use parameters to provide the user with flexibility and ease of use to generate SATS demand for different scenarios. Several case studies are included to illustrate the use of the models, which are useful to identify the need for a new air traffic management system to cope with SATS.
Acosta, Diana M.; Guynn, Mark D.; Wahls, Richard A.; DelRosario, Ruben,
The future of aviation will benefit from research in aircraft design and air transportation management aimed at improving efficiency and reducing environmental impacts. This paper presents civil transport aircraft design trends and opportunities for improving vehicle and system-level efficiency. Aircraft design concepts and the emerging technologies critical to reducing thrust specific fuel consumption, reducing weight, and increasing lift to drag ratio currently being developed by NASA are discussed. Advancements in the air transportation system aimed towards system-level efficiency are discussed as well. Finally, the paper describes the relationship between the air transportation system, aircraft, and efficiency. This relationship is characterized by operational constraints imposed by the air transportation system that influence aircraft design, and operational capabilities inherent to an aircraft design that impact the air transportation system.
Bowen, Brent D.; Holmes, Bruce J.; Hansen, Frederick
The National Aeronautics and Space Administration (NASA), U.S. Department of Transportation, Federal Aviation Administration, industry stakeholders, and academia, have joined forces to pursue the NASA National General Aviation Roadmap leading to a Small Aircraft Transportation System (SATS). This strategic undertaking has a 25-year goal to bring the next-generation technologies and improve travel between remote communities and transportation centers in urban areas by utilizing the nation's 5,400 public use general aviation airports. To facilitate this initiative, a comprehensive upgrade of public infrastructure must be planned, coordinated, and implemented within the framework of the national air transportation system. The Nebraska NASA EPSCoR Program has proposed to deliver research support in key public infrastructure areas in coordination with the General Aviation Program Office at the NASA Langley Research Center. Ultimately, SATS may permit tripling aviation system throughput capacity by tapping the underutilized general aviation facilities to achieve the national goal of doorstep-to-destination travel at four times the speed of highways for the nation's suburban, rural, and remote communities.
Optical communications for transport aircraft are discussed. The problem involves: increasing demand for radio-frequency bands from an enlarging pool of users (aircraft, ground and sea vehicles, fleet operators, traffic control centers, and commercial radio and television); desirability of providing high-bandwidth dedicated communications to and from every aircraft in the National Airspace System; need to support communications, navigation, and surveillance for a growing number of aircraft; and improved meteorological observations by use of probe aircraft. The solution involves: optical signal transmission support very high data rates; optical transmission of signals between aircraft, orbiting satellites, and ground stations, where unobstructed line-of-sight is available; conventional radio transmissions of signals between aircraft and ground stations, where optical line-of-sight is unavailable; and radio priority given to aircraft in weather.
Coleman, Anthony S.; Hansen, Irving G.
NASA is pursuing a program in Advanced Subsonic Transport (AST) to develop the technology for a highly reliable Fly-By-Light/Power-By-WIre aircraft. One of the primary objectives of the program is to develop the technology base for confident application of integrated PBW components and systems to transport aircraft to improve operating reliability and efficiency. Technology will be developed so that the present hydraulic and pneumatic systems of the aircraft can be systematically eliminated and replaced by electrical systems. These motor driven actuators would move the aircraft wing surfaces as well as the rudder to provide steering controls for the pilot. Existing aircraft electrical systems are not flight critical and are prone to failure due to Electromagnetic Interference (EMI) (1), ground faults and component failures. In order to successfully implement electromechanical flight control actuation, a Power Management and Distribution (PMAD) System must be designed having a reliability of 1 failure in 10(exp +9) hours, EMI hardening and a fault tolerance architecture to ensure uninterrupted power to all aircraft flight critical systems. The focus of this paper is to analyze, define, and describe technically challenging areas associated with the development of a Power By Wire Aircraft and typical requirements to be established at the box level. The authors will attempt to propose areas of investigation, citing specific military standards and requirements that need to be revised to accommodate the 'More Electric Aircraft Systems'.
Fly-by-wire flight control systems are becoming more common in both civil and military aircraft. These systems give many benefits, but also present a new set of problems due to their increased complexity compared to conventional systems and the larger choice of options that they provide. The work presented here considers the application of fly-by-wire to a generic regional transport aircraft. The flying qualities criteria used for typical flying qualities evaluations are described...
Galvin, James J., Jr.
The National Aeronautics and Space Administration (NASA) is leading a research effort to develop a Small Aircraft Transportation System (SATS) that will expand air transportation capabilities to hundreds of underutilized airports in the United States. Most of the research effort addresses the technological development of the small aircraft as well as the systems to manage airspace usage and surface activities at airports. The Federal Aviation Administration (FAA) will also play a major role in the successful implementation of SATS, however, the administration is reluctant to embrace the unproven concept. The purpose of the research presented in this dissertation is to determine if the FAA can pursue a resource management strategy that will support the current radar-based Air Traffic Control (ATC) system as well as a Global Positioning Satellite (GPS)-based ATC system required by the SATS. The research centered around the use of the System Dynamics modeling methodology to determine the future behavior of the principle components of the ATC system over time. The research included a model of the ATC system consisting of people, facilities, equipment, airports, aircraft, the FAA budget, and the Airport and Airways Trust Fund. The model generated system performance behavior used to evaluate three scenarios. The first scenario depicted the base case behavior of the system if the FAA continued its current resource management practices. The second scenario depicted the behavior of the system if the FAA emphasized development of GPS-based ATC systems. The third scenario depicted a combined resource management strategy that supplemented radar systems with GPS systems. The findings of the research were that the FAA must pursue a resource management strategy that primarily funds a radar-based ATC system and directs lesser funding toward a GPS-based supplemental ATC system. The most significant contribution of this research was the insight and understanding gained of how
Holmes, Bruce J.
This paper presents trends and forces that shape 21 st century demand for higher-speed personal air transportation and outlines guidance developed by NASA in partnership with other federal and state government and industry partners, for Small Aircraft Transportation System (SATS) investment and partnership planning.
Jones, D. R.; Parrish, R. V.; Person, L. H., Jr.; Old, J. L.
With the advent of digital avionics, the workload of the pilot in a moderen transport aircraft is increasing significantly. This situation makes it necessary to reduce pilot workload with the aid of new advanced technologies. As part of an effort to improve information management systems, NASA has, therefore, studied an advanced concept for managing the navigational tasks of a modern transport aircraft. This concept is mainly concerned with the simplification of the pilot interface. The advanced navigational system provides a simple method for a pilot to enter new waypoints to change his flight plan because of heavy traffic, adverse weather conditions, or other reasons. The navigational system was implemented and evaluated in a flight simulator representative of a modern transport aircraft. Attention is given to the simulator, flight simulation, multimode devices, and the navigational system.
Liddle, Stephen C; Crowther, William J.; Jabbal, Mark
This article is placed here with permission from the Royal Aeronautical Society - Copyright @ 2009 Royal Aeronautical Society The use of flow control (FC) technology on civil transport aircraft is seen as a potential means of providing a step change in aerodynamic performance in the 2020 time frame. There has been extensive research into the flow physics associated with FC. This paper focuses on developing an understanding of the costs and design drivers associated with the systems needed ...
Viken, Sally A.; Brooks, Frederick M.; Johnson, Sally C.
It has become evident that our commercial air transportation system is reaching its peak in terms of capacity, with numerous delays in the system and the demand still steadily increasing. NASA, FAA, and the National Consortium for Aviation Mobility (NCAM) have partnered to aid in increasing the mobility throughout the United States through the Small Aircraft Transportation System (SATS) project. The SATS project has been a five-year effort to provide the technical and economic basis for further national investment and policy decisions to support a small aircraft transportation system. The SATS vision is to enable people and goods to have the convenience of on-demand point-to-point travel, anywhere, anytime for both personal and business travel. This vision can be obtained by expanding near all-weather access to more than 3,400 small community airports that are currently under-utilized throughout the United States. SATS has focused its efforts on four key operating capabilities that have addressed new emerging technologies, procedures, and concepts to pave the way for small aircraft to operate in nearly all weather conditions at virtually any runway in the United States. These four key operating capabilities are: Higher Volume Operations at Non-Towered/Non-Radar Airports, En Route Procedures and Systems for Integrated Fleet Operations, Lower Landing Minimums at Minimally Equipped Landing Facilities, and Increased Single Pilot Performance. The SATS project culminated with the 2005 SATS Public Demonstration in Danville, Virginia on June 5th-7th, by showcasing the accomplishments achieved throughout the project and demonstrating that a small aircraft transportation system could be viable. The technologies, procedures, and concepts were successfully demonstrated to show that they were safe, effective, and affordable for small aircraft in near all weather conditions. The focus of this paper is to provide an overview of the technical and operational feasibility of the
Tarry, Scott E.; Bowen, Brent D.; Nickerson, Jocelyn S.
The aviation industry is an integral part of the world s economy. Travelers have consistently chosen aviation as their mode of transportation as it is reliable, time efficient and safe. The out- dated Hub and Spoke system, coupled with high demand, has led to delays, cancellations and gridlock. NASA is developing innovative solutions to these and other air transportation problems. This research is being conducted through partnerships with federal agencies, industry stakeholders, and academia, specifically the University of Nebraska at Omaha. Each collaborator is pursuing the NASA General Aviation Roadmap through their involvement in the expansion of the Small Aircraft Transportation System (SATS). SATS will utilize technologically advanced small aircraft to transport travelers to and from rural and isolated communities. Additionally, this system will provide a safe alternative to the hub and spoke system, giving more time to more people through high-speed mobility and increased accessibility.
Viken, Sally A.; Brooks, Frederick M.
The Small Aircraft Transportation System (SATS) project has been a five-year effort fostering research and development that could lead to the transformation of our country s air transportation system. It has become evident that our commercial air transportation system is reaching its peak in terms of capacity, with numerous delays in the system and the demand keeps steadily increasing. The SATS vision is to increase mobility in our nation s transportation system by expanding access to more than 3400 small community airports that are currently under-utilized. The SATS project has focused its efforts on four key operating capabilities that have addressed new emerging technologies and procedures to pave the way for a new way of air travel. The four key operating capabilities are: Higher Volume Operations at Non-Towered/Non-Radar Airports, En Route Procedures and Systems for Integrated Fleet Operations, Lower Landing Minimums at Minimally Equipped Landing Facilities, and Increased Single Pilot Performance. These four capabilities are key to enabling low-cost, on-demand, point-to-point transportation of goods and passengers utilizing small aircraft operating from small airports. The focus of this paper is to discuss the technical and operational feasibility of the four operating capabilities and demonstrate how they can enable a small aircraft transportation system.
Abbott, Terence S.; Consiglio, Maria C.; Baxley, Brian T.; Williams, Daniel M.; Conway, Sheila R.
This document expands the Small Aircraft Transportation System, (SATS) Higher Volume Operations (HVO) concept to include off-nominal conditions. The general philosophy underlying the HVO concept is the establishment of a newly defined area of flight operations called a Self-Controlled Area (SCA). During periods of poor weather, a block of airspace would be established around designated non-towered, non-radar airports. Aircraft flying enroute to a SATS airport would be on a standard instrument flight rules flight clearance with Air Traffic Control providing separation services. Within the SCA, pilots would take responsibility for separation assurance between their aircraft and other similarly equipped aircraft. Previous work developed the procedures for normal HVO operations. This document provides details for off-nominal and emergency procedures for situations that could be expected to occur in a future SCA.
Williams, Daniel M.; Murdoch, Jennifer L.; Adams, Catherine H.
This paper provides a summary of conclusions from the Small Aircraft Transportation System (SATS) Higher Volume Operations (HVO) Flight Experiment which NASA conducted to determine pilot acceptability of the HVO concept for normal conditions. The SATS HVO concept improves efficiency at non-towered, non-radar airports in Instrument Meteorological Conditions (IMC) while achieving a level of safety equal to today s system. Reported are results from flight experiment data that indicate that the SATS HVO concept is viable. The success of the SATS HVO concept is based on acceptable pilot workload, performance, and subjective criteria when compared to the procedural control operations in use today at non-towered, non-radar controlled airfields in IMC. The HVO Flight Experiment, flown on NASA's Cirrus SR22, used a subset of the HVO Simulation Experiment scenarios and evaluation pilots in order to validate the simulation experiment results. HVO and Baseline (today s system) scenarios flown included: single aircraft arriving for a GPS non-precision approach; aircraft arriving for the approach with multiple traffic aircraft; and aircraft arriving for the approach with multiple traffic aircraft and then conducting a missed approach. Results reveal that all twelve low-time instrument-rated pilots preferred SATS HVO when compared to current procedural separation operations. These pilots also flew the HVO procedures safely and proficiently without additional workload in comparison to today s system (Baseline). Detailed results of pilot flight technical error, and their subjective assessments of workload and situation awareness are presented in this paper.
Tarry, Scott E.; Bowen, Brent D.
America's air transport system is currently faced with two equally important dilemmas. First, congestion and delays associated with the overburdened hub and spoke system will continue to worsen unless dramatic changes are made in the way air transportation services are provided. Second, many communities and various regions of the country have not benefited from the air transport system, which tends to focus its attention on major population centers. An emerging solution to both problems is a Small Aircraft Transportation System (SATS), which will utilize a new generation of advanced small aircraft to provide air transport services to those citizens who are poorly served by the hub and spoke system and those citizens who are not served at all. Using new innovations in navigation, communication, and propulsion technologies, these aircraft will enable users to safely and reliably access the over 5,000 general aviation landing facilities around the United States. A small aircraft transportation system holds the potential to revolutionize the way Americans travel and to greatly enhance the use of air transport as an economic development tool in rural and isolated communities across the nation.
Baxley, B.; Williams, D.; Consiglio, M.; Conway, S.; Adams, C.; Abbott, T.
The ability to conduct concurrent, multiple aircraft operations in poor weather, at virtually any airport, offers an important opportunity for a significant increase in the rate of flight operations, a major improvement in passenger convenience, and the potential to foster growth of charter operations at small airports. The Small Aircraft Transportation System, (SATS) Higher Volume Operations (HVO) concept is designed to increase traffic flow at any of the 3400 nonradar, non-towered airports in the United States where operations are currently restricted to one-in/one-out procedural separation during Instrument Meteorological Conditions (IMC). The concept's key feature is pilots maintain their own separation from other aircraft using procedures, aircraft flight data sent via air-to-air datalink, cockpit displays, and on-board software. This is done within the Self-Controlled Area (SCA), an area of flight operations established during poor visibility or low ceilings around an airport without Air Traffic Control (ATC) services. The research described in this paper expands the HVO concept to include most off-nominal situations that could be expected to occur in a future SATS environment. The situations were categorized into routine off-nominal operations, procedural deviations, equipment malfunctions, and aircraft emergencies. The combination of normal and off-nominal HVO procedures provides evidence for an operational concept that is safe, requires little ground infrastructure, and enables concurrent flight operations in poor weather.
Full Text Available Avionics of the present day comprises advanced technology and software-intensive systems. Earlier generation avionics constituted federated architecture and used line replaceable units (LRUs having individual resources for each application with redundant hardware and software. However with the advancement of technology, methods,and mechanisms, the industry moved quite rapidly towards the integrated architecture called integrated modular avionics (IMA. Over the last decade there has been tremendous growth in these technologies which has resulted in reduced weight, volume, and developmental efforts. Usage of complex systems with advanced technologies and their certification for use in civil aircraft are the key issues to be addressed even today. Avionics of general aviation aircraft consists of typical systems like communication, navigation, display, radar, engine indication and data acquisition and recoding systems. These can be realised in federated as well as integrated architectures. TheLRUs requirements for avionics sub-system depends on the certification standards like FAR 23 or FAR 25. The whole cycle of architecture definition, integration, testing and means of compliance of the complete suite is the major activity in any new aircraft development programme. Development of ground-based test facilities and proper maintenance of the entire system on aircraft are other important activities in such programmes. These issues are presented in this paper for a typical light transport aircraft (LTA. The new technologies with their relevance, merits/de-merits, awareness of the global systems being adopted, etc., which are being attempted as indigenousdesign and development, are also presented.Defence Science Journal, 2011, 61(4, pp.289-298, DOI:http://dx.doi.org/10.14429/dsj.61.1090
Carrreno, Victor A.; Gottliebsen, Hanne; Butler, Ricky; Kalvala, Sara
New concepts for automating air traffic management functions at small non-towered airports raise serious safety issues associated with the software implementations and their underlying key algorithms. The criticality of such software systems necessitates that strong guarantees of the safety be developed for them. In this paper we present a formal method for modeling and verifying such systems using the PVS theorem proving system. The method is demonstrated on a preliminary concept of operation for the Small Aircraft Transportation System (SATS) project at NASA Langley.
Williams, Daniel; Consiglio, Maria; Murdoch, Jennifer; Adams, Catherine
This document provides a preliminary validation of the Small Aircraft Transportation System (SATS) Higher Volume Operations (HVO) concept for normal conditions. Initial results reveal that the concept provides reduced air traffic delays when compared to current operations without increasing pilot workload. Characteristic to the SATS HVO concept is the establishment of a newly defined area of flight operations called a Self-Controlled Area (SCA) which would be activated by air traffic control (ATC) around designated non-towered, non-radar airports. During periods of poor visibility, SATS pilots would take responsibility for separation assurance between their aircraft and other similarly equipped aircraft in the SCA. Using onboard equipment and simple instrument flight procedures, they would then be better able to approach and land at the airport or depart from it. This concept would also require a new, ground-based automation system, typically located at the airport that would provide appropriate sequencing information to the arriving aircraft. Further validation of the SATS HVO concept is required and is the subject of ongoing research and subsequent publications.
Holmes, Bruce J.
The National Aeronautics and Space Administration (NASA), Federal Aviation Administration, as well as state, industry, and academia partners have joined forces to pursue the NASA National General Aviation Roadmap leading to a Small Aircraft Transportation System (SATS). This long-term strategic undertaking has a goal to bring next-generation technologies and improve air access to small communities. The envisioned outcome is to improve travel between remote communities and transportation centers in urban areas by utilizing a new generation of single-pilot light planes for personal and business transportation between the nation's 5,400 public use general aviation airports. Current NASA investments in aircraft technologies are enabling industry to bring affordable, safe, and easy-to-use features to the marketplace, including "Highway in the Sky" glass cockpit operating capabilities, affordable crash worthy composite airframes, more efficient IFR flight training, and revolutionary engines. To facilitate this initiative, a comprehensive upgrade of public infrastructure must be planned, coordinated, and implemented within the framework of the national air transportation system. State partnerships are proposed to coordinate research support in key public infrastructure areas. Ultimately, SATS may permit more than tripling aviation system throughput capacity by tapping the under-utilized general aviation facilities to achieve the national goal of doorstep-to-destination travel at four times the speed of highways for the nation's suburban, rural, and remote communities.
Millsaps, Gary D.; Yackovetsky, Robert E. (Technical Monitor)
It is acknowledged that the aviation and aerospace industries are primary forces influencing the industrial development and economic well being of the United States and many countries around the world. For decades the US national air transportation system has been the model of success - safely and efficiently moving people, cargo, goods and services and generating countless benefits throughout the global community; however, the finite nature of the system and many of its components is becoming apparent. Without measurable increases in the capacity of the national air transportation system, delays and service delivery failures will eventually become intolerable. Although the recent economic slowdown has lowered immediate travel demands, that trend is reversing and cargo movement remains high. Research data indicates a conservative 2.5-3.0% annual increase in aircraft operations nationwide through 2017. Such growth will place additional strains upon a system already experiencing capacity constraints. The stakeholders of the system will continue to endure ever-increasing delays and abide lesser levels of service to many lower population density areas of the country unless more efficient uses of existing and new transportation resources are implemented. NASA s Small Aircraft Transportation System program (SATS) is one of several technologies under development that are aimed at using such resources more effectively. As part of this development effort, this report is the first in a series outlining the findings and recommendations resulting from a comprehensive program of multi-level analyses and system engineering efforts undertaken by NASA Langley Research Center s Systems Analysis Branch (SAB). These efforts are guided by a commitment to provide systems-level analysis support for the SATS program. Subsequent efforts will build upon this early work to produce additional analyses and benefits studies needed to provide the technical and economic basis for national
Williams, Daniel M.
Described is the research process that NASA researchers used to validate the Small Aircraft Transportation System (SATS) Higher Volume Operations (HVO) concept. The four phase building-block validation and verification process included multiple elements ranging from formal analysis of HVO procedures to flight test, to full-system architecture prototype that was successfully shown to the public at the June 2005 SATS Technical Demonstration in Danville, VA. Presented are significant results of each of the four research phases that extend early results presented at ICAS 2004. HVO study results have been incorporated into the development of the Next Generation Air Transportation System (NGATS) vision and offer a validated concept to provide a significant portion of the 3X capacity improvement sought after in the United States National Airspace System (NAS).
Baxley, B.; Williams, D.; Consiglio, M.; Adams, C.; Abbott, T.
The ability to conduct concurrent, multiple aircraft operations in poor weather at virtually any airport offers an important opportunity for a significant increase in the rate of flight operations, a major improvement in passenger convenience, and the potential to foster growth of operations at small airports. The Small Aircraft Transportation System, (SATS) Higher Volume Operations (HVO) concept is designed to increase capacity at the 3400 non-radar, non-towered airports in the United States where operations are currently restricted to one-in/one-out procedural separation during low visibility or ceilings. The concept s key feature is that pilots maintain their own separation from other aircraft using air-to-air datalink and on-board software within the Self-Controlled Area (SCA), an area of flight operations established during poor visibility and low ceilings around an airport without Air Traffic Control (ATC) services. While pilots self-separate within the SCA, an Airport Management Module (AMM) located at the airport assigns arriving pilots their sequence based on aircraft performance, position, winds, missed approach requirements, and ATC intent. The HVO design uses distributed decision-making, safe procedures, attempts to minimize pilot and controller workload, and integrates with today's ATC environment. The HVO procedures have pilots make their own flight path decisions when flying in Instrument Metrological Conditions (IMC) while meeting these requirements. This paper summarizes the HVO concept and procedures, presents a summary of the research conducted and results, and outlines areas where future HVO research is required. More information about SATS HVO can be found at http://ntrs.nasa.gov.
Bowen, Brent D.
The National Aeronautics and Space Administration (NASA), U.S. Department of Transportation, Federal Aviation Administration, industry stakeholders, and academia, have joined forces to pursue the NASA National General Aviation Roadmap leading to a Small Aircraft Transportation System (SATS). This strategic undertaking has a 25-year goal to bring next-generation technologies and improve travel between remote communities and transportation centers in urban areas by utilizing the nation's 5,400 public-use general aviation airports. To facilitate this initiative, a comprehensive upgrade of public infrastructure must be planned, coordinated, and implemented within the framework of the national air transportation system. The Nebraska NASA EPSCoR Program has proposed to deliver research support in key public infrastructure areas in coordination with the General Aviation Program Office at the NASA Langley Research Center. Ultimately, SATS may permit tripling aviation system throughput capacity by tapping the underutilized general aviation facilities to achieve the national goal of doorstep-to-destination travel at four times the speed of highways for the nation's suburban, rural, and remote communities.
ONeil, Patrick D.; Tarry, Scott E.
The following collection of research summaries are submitted as fulfillment of a request from NASA LaRC to conduct research into existing enabling technologies that support the development of the Small Aircraft Transportation System aircraft and accompanying airspace management infrastructure. Due to time and fiscal constraints, the included studies focus primarily on visual systems and architecture, flight control design, instrumentation and display, flight deck design considerations, Human-Machine Interface issues, and supporting augmentation technologies and software. This collation of summaries is divided in sections in an attempt to group similar technologies and systems. However, the reader is advised that many of these studies involve multiple technologies and systems that span across many categories. Because of this fact, studies are not easily categorized into single sections. In an attempt to help the reader more easily identify topics of interest, a SATS application description is provided for each summary. In addition, a list of acronyms provided at the front of the report to aid the reader.
UijtdeHaag, Maarten; Thomas, Robert; Rankin, James R.
The report discusses the architecture and the flight test results of a 3-Dimensional Cockpit Display of Traffic and terrain Information (3D-CDTI). The presented 3D-CDTI is a perspective display format that combines existing Synthetic Vision System (SVS) research and Automatic Dependent Surveillance-Broadcast (ADS-B) technology to improve the pilot's situational awareness. The goal of the 3D-CDTI is to contribute to the development of new display concepts for NASA's Small Aircraft Transportation System research program. Papers were presented at the PLANS 2002 meeting and the ION-GPS 2002 meeting. The contents of this report are derived from the results discussed in those papers.
WU Huzi; GENG Jianzhong; TANG Changhong; LI Wei
The corresponding corrected method is proposed for the INS (INS-Inertial Navigation System) accumulated error of large transport aircraft.System errors contain aircraft position error,altitude error and speed error,one is increasing the accuracy of hardware; the other is development of low cost software algorithms.Because of improving hardware is more difficult in my country at present,developing software algorithms is essential way,which have been validated in my types of airplane.The combined heuristic algorithms (ABPNN,Advanced Back-propagation neural networks algorithm and LSM-least square method) are presented,which incorporates the effects of flight region and measured terrain height data by radar and barometer.Based on this algorithm,the appropriate match region was gotten by recognition of fiducial digital map in real time online.In process of work,the minimum of position error as a cost function and the constraint conditions are gave,the flight positions are recognized in real time and continuously,least sum of square is calculated based on LSM,in other words,the optimized result is obtained.The simulation case demonstrate that the method is very successful,the correct rate of recognition is more 90 percent.In words,the algorithm presented is economical,validation and effective.
Englar, Robert J.; Willie, F. Scott; Lee, Warren J.
In the Task I portion of this NASA research grant, configuration development and experimental investigations have been conducted on a series of pneumatic high-lift and control surface devices applied to a generic High Speed Civil Transport (HSCT) model configuration to determine their potential for improved aerodynamic performance, plus stability and control of higher performance aircraft. These investigations were intended to optimize pneumatic lift and drag performance; provide adequate control and longitudinal stability; reduce separation flowfields at high angle of attack; increase takeoff/climbout lift-to-drag ratios; and reduce system complexity and weight. Experimental aerodynamic evaluations were performed on a semi-span HSCT generic model with improved fuselage fineness ratio and with interchangeable plain flaps, blown flaps, pneumatic Circulation Control Wing (CCW) high-lift configurations, plain and blown canards, a novel Circulation Control (CC) cylinder blown canard, and a clean cruise wing for reference. Conventional tail power was also investigated for longitudinal trim capability. Also evaluated was unsteady pulsed blowing of the wing high-lift system to determine if reduced pulsed mass flow rates and blowing requirements could be made to yield the same lift as that resulting from steady-state blowing. Depending on the pulsing frequency applied, reduced mass flow rates were indeed found able to provide lift augmentation at lesser blowing values than for the steady conditions. Significant improvements in the aerodynamic characteristics leading to improved performance and stability/control were identified, and the various components were compared to evaluate the pneumatic potential of each. Aerodynamic results were provided to the Georgia Tech Aerospace System Design Lab. to conduct the companion system analyses and feasibility study (Task 2) of theses concepts applied to an operational advanced HSCT aircraft. Results and conclusions from these
Murphy, Patrick C.; Klein, Vladislav
Continued studies have been undertaken to investigate and develop aerodynamic models that predict aircraft response in nonlinear unsteady flight regimes for transport configurations. The models retain conventional static and dynamic terms but replace conventional acceleration terms with indicial functions. In the Subsonic Fixed Wing Project of the NASA Fundamental Aeronautics Program and the Integrated Resilient Aircraft Controls project of the NASA Aviation Safety Program one aspect of the research is to apply these current developments to transport configurations to facilitate development of advanced simulation and control design technology. This paper continues development and application of a more general modeling methodology to the NASA Langley Generic Transport Model, a sub-scale flight test vehicle. In the present study models for the lateral-directional aerodynamics are developed.
Consiglio, Maria C.; Carreno, Victor A.; Williams, Daniel M.; Munoz, Cesar
A multilayer approach to the prevention of conflicts due to the loss of aircraft-to-aircraft separation which relies on procedures and on-board automation was implemented as part of the SATS HVO Concept of Operations. The multilayer system gives pilots support and guidance during the execution of normal operations and advance warning for procedure deviations or off-nominal operations. This paper describes the major concept elements of this multilayer approach to separation assurance and conflict prevention and provides the rationale for its design. All the algorithms and functionality described in this paper have been implemented in an aircraft simulation in the NASA Langley Research Center s Air Traffic Operation Lab and on the NASA Cirrus SR22 research aircraft.
Carreno, Victor; Munoz, Cesar
A critical factor in the adoption of any new aeronautical technology or concept of operation is safety. Traditionally, safety is accomplished through a rigorous process that involves human factors, low and high fidelity simulations, and flight experiments. As this process is usually performed on final products or functional prototypes, concept modifications resulting from this process are very expensive to implement. This paper describe an approach to system safety that can take place at early stages of a concept design. It is based on a set of mathematical techniques and tools known as formal methods. In contrast to testing and simulation, formal methods provide the capability of exhaustive state exploration analysis. We present the safety analysis and verification performed for the Small Aircraft Transportation System (SATS) Concept of Operations (ConOps). The concept of operations is modeled using discrete and hybrid mathematical models. These models are then analyzed using formal methods. The objective of the analysis is to show, in a mathematical framework, that the concept of operation complies with a set of safety requirements. It is also shown that the ConOps has some desirable characteristic such as liveness and absence of dead-lock. The analysis and verification is performed in the Prototype Verification System (PVS), which is a computer based specification language and a theorem proving assistant.
Pirkl, Martin; Tospann, Franz-Jose
This paper presents a guideline to meet the requirements of forward looking sensors of an enhanced vision system for both military and civil transport aircraft. It gives an update of a previous publication with special respect to airborne application. For civil transport aircraft an imaging mm-wave radar is proposed as the vision sensor for an enhanced vision system. For military air transport an additional high-performance weather radar should be combined with the mm-wave radar to enable advanced situation awareness, e.g. spot-SAR or air to air operation. For tactical navigation the mm-wave radar is useful due to its ranging capabilities. To meet these requirements the HiVision radar was developed and tested. It uses a robust concept of electronic beam steering and will meet the strict price constraints of transport aircraft. Advanced image processing and high frequency techniques are currently developed to enhance the performance of both the radar image and integration techniques. The advantages FMCW waveform even enables a sensor with low probability of intercept and a high resistance against jammer. The 1997 highlight will be the optimizing of the sensor and flight trials with an enhanced radar demonstrator.
Mavris, Dimitri N.; Tai, Jimmy C.; Kirby, Michelle M.; Roth, Bryce A.
The primary aspiration of this study was to objectively assess the feasibility of the application of a low speed pneumatic technology, in particular Circulation Control (CC) to an HSCT concept. Circulation Control has been chosen as an enabling technology to be applied on a generic High Speed Civil Transport (HSCT). This technology has been proven for various subsonic vehicles including flight tests on a Navy A-6 and computational application on a Boeing 737. Yet, CC has not been widely accepted for general commercial fixed-wing use but its potential has been extensively investigated for decades in wind tunnels across the globe for application to rotorcraft. More recently, an experimental investigation was performed at Georgia Tech Research Institute (GTRI) with application to an HSCT-type configuration. The data from those experiments was to be applied to a full-scale vehicle to assess the impact from a system level point of view. Hence, this study attempted to quantitatively assess the impact of this technology to an HSCT. The study objective was achieved in three primary steps: 1) Defining the need for CC technology; 2) Wind tunnel data reduction; 3) Detailed takeoff/landing performance assessment. Defining the need for the CC technology application to an HSCT encompassed a preliminary system level analysis. This was accomplished through the utilization of recent developments in modern aircraft design theory at Aerospace Systems Design Laboratory (ASDL). These developments include the creation of techniques and methods needed for the identification of technical feasibility show stoppers. These techniques and methods allow the designer to rapidly assess a design space and disciplinary metric enhancements to enlarge or improve the design space. The takeoff and landing field lengths were identified as the concept "show-stoppers". Once the need for CC was established, the actual application of data and trends was assessed. This assessment entailed a reduction of the
Bowen, Brent (Editor); Holmes, Bruce; Gogos, George; Narayanan, Ram; Smith, Russell; Woods, Sara
, Codes, and Strategic Enterprises. During the first year of funding, Nebraska established open and frequent lines of communication with university affairs officers and other key personnel at all NASA Centers and Enterprises, and facilitated the development of collaborations between and among junior faculty in the state and NASA researchers. As a result, Nebraska initiated a major research cluster, the Small Aircraft Transportation System Nebraska Implementation Template.
Wagner, R. D.
The incorporation of laminar flow control into transport aircraft is discussed. Design concepts for the wing surface panel of laminar flow control transport aircraft are described. The development of small amounts of laminar flow on small commercial transports with natural or hybrid flow control is examined. Techniques for eliminating the insect contamination problem in the leading-edge region are proposed.
Full Text Available In accordance with Air Force requirements, the comparative analysis of short/medium transport aircraft comes to sustain procurement decision of short/medium transport aircraft. This paper presents, in short, the principles and the results of the comparative analysis for short/medium military transport aircraft.
Lohr, Gary W.; Williams, Dan; Abbott, Terence; Baxley, Brian; Greco, Adam; Ridgway, Richard
The Small Aircraft Transportation System Higher Volume Operations (SATS HVO) concept holds the promise for increased efficiency and throughput at many of the nations under-used airports. This concept allows for concurrent operations at uncontrolled airports that under today s procedures are restricted to one arrival or one departure operation at a time, when current-day IFR separation standards are applied. To allow for concurrent operations, SATS HVO proposes several fundamental changes to today's system. These changes include: creation of dedicated airspace, development of new procedures and communications (phraseologies), and assignment of roles and responsibilities for pilots and controllers, among others. These changes would affect operations on the airborne side (pilot) as well as the groundside (controller and air traffic flow process). The focus of this paper is to discuss some of the issues and potential problems that have been considered in the development of the SATS HVO concept, in particular from the ground side perspective. Reasonable solutions to the issues raised here have been proposed by the SATS HVO team, and are discussed in this paper.
National Aeronautics and Space Administration — This proposal defines innovative aerodynamic concepts and technology goals aimed at vehicle efficiency for future subsonic aircraft in the 2020 ? 2030 timeframe....
White, John A.
Aircraft manufacturers are developing fiber optic technology to exploit the benefits in system performance and manufacturing cost reduction. The fiber optic systems have high bandwidths and exceptional Electromagnetic Interference immunity that exceeds all new aircraft design requirements. Additionally, aircraft manufacturers have shown production readiness of fiber optic systems and design feasibility.
Williams, L. J.
In connection with a request for a report coming from a U.S. Senate committee, NASA formed a Small Transport Aircraft Technology (STAT) team in 1978. STAT was to obtain information concerning the technical improvements in commuter aircraft that would likely increase their public acceptance. Another area of study was related to questions regarding the help which could be provided by NASA's aeronautical research and development program to commuter aircraft manufacturers with respect to the solution of technical problems. Attention is given to commuter airline growth, current commuter/region aircraft and new aircraft in development, prospects for advanced technology commuter/regional transports, and potential benefits of advanced technology. A list is provided of a number of particular advances appropriate to small transport aircraft, taking into account small gas turbine engine component technology, propeller technology, three-dimensional wing-design technology, airframe aerodynamics/propulsion integration, and composite structure materials.
Harlow, Charles; Zhu, Weihong
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.
Pavlin, Stanislav; Roguljić, Slavko
Airport aprons are areas for aircraft handling, parking and maintenance. According to international rules the number of positions at the apron has to be at least equal to the number of aircraft staying at any one time at the airport. The air traffic at Split Airport increased rapidly in the mid-90s when it became the UN logistics base for Bosnia and Herzegovina. There were nomeans nor free space for further expansion of the apron, so the traffic had to be reorganised and re-coordinated. Alter...
Dugan, J. F., Jr.
Review of the procedures used to select engines for transport and combat aircraft by illustrating the procedures for a long haul CTOL transport, a short haul VTOL transport, a long range SST, and a fighter aircraft. For the CTOL transport, it is shown that advances in noise technology and advanced turbine cooling technology will greatly reduce the airplane performance penalties associated with achieving low noise goals. A remote lift fan powered by a turbofan air generator is considered for the VTOL aircraft. In this case, the lift fan pressure ratio which maximizes payload also comes closest to meeting the noise goal. High turbine temperature in three different engines is considered for the SST. Without noise constraints it leads to an appreciable drop in DOC, but with noise constraints the reduction in DOC is very modest. For the fighter aircraft it is shown how specific excess power requirements play the same role in engine selection as noise constraints for commercial airplanes.
Bartle, John R.
The objective of SATS is to reduce gridlock at hubs, reduce travel times, allow for personal control over travel, and anticipate demand shifts resulting from a migration from suburbs to rural places. The technology is presently available and economical to produce SATS aircraft. The public issue centers on the airports. SATS is a federal program, and many airports in the U.S. are under the control of local governments. The scope of the objective will require thousands of airports in rural and suburban areas to modify their infrastructure and increase their investment. Researchers at the University of Nebraska at Omaha (UNO), and others at other institutions, have prepared reports surveying the relevant issues of implementing SATS. Our UNO team focused on the issues of policy implementation, economic development, management, and finance specific to Nebraska. We are finding that these issues are similar to those in other states in our region and other rural states. This paper discusses how this investment might be financed.
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.
A brief overview is given of the on-going NASA Automated Cooperative Trajectories project. Current status and upcoming work is previewed. The motivating factors and innovative aspects of ACT are discussed along with technical challenges and the expected system-level impacts if the project is successful. Preliminary results from the NASA G-III hardware in the loop simulation are included.
C.M. Ananda; K.G. Venkatanarayana; Preme M.; Raghu M.
Avionics of the present day comprises advanced technology and software-intensive systems. Earlier generation avionics constituted federated architecture and used line replaceable units (LRUs) having individual resources for each application with redundant hardware and software. However with the advancement of technology, methods,and mechanisms, the industry moved quite rapidly towards the integrated architecture called integrated modular avionics (IMA). Over the last decade there has been tre...
Hopkins, A. L.; Martin, J. H.; Brock, L. D.; Jansson, D. G.; Serben, S.; Smith, T. B.; Hanley, L. D.
Candidate data communication techniques are identified, including dedicated links, local buses, broadcast buses, multiplex buses, and mesh networks. The design methodology for mesh networks is then discussed, including network topology and node architecture. Several concepts of power distribution are reviewed, including current limiting and mesh networks for power. The technology issues of packaging, transmission media, and lightning are addressed, and, finally, the analysis tools developed to aid in the communication design process are described. There are special tools to analyze the reliability and connectivity of networks and more general reliability analysis tools for all types of systems.
The National Airspace System (NAS) in the United States had an inventory of 5,156 big jets at the end of December 2002, of which 4,085 were narrow bodies, and 1,071 were wide bodies. In addition, there were 1,180 regional jets and 660 turboprops in the system at that time. Empirical research reveals that there is a critical link between the flow of scheduled passenger services and the choice of aircraft used by the airlines in serving market pair demand. This relationship can be empirically r...
Gundy-Burlet, Karen; Krishnakumar, K.; Limes, Greg; Bryant, Don
This paper examines the feasibility, potential benefits and implementation issues associated with retrofitting a neural-adaptive flight control system (NFCS) to existing transport aircraft, including both cable/hydraulic and fly-by-wire configurations. NFCS uses a neural network based direct adaptive control approach for applying alternate sources of control authority in the presence of damage or failures in order to achieve desired flight control performance. Neural networks are used to provide consistent handling qualities across flight conditions, adapt to changes in aircraft dynamics and to make the controller easy to apply when implemented on different aircraft. Full-motion piloted simulation studies were performed on two different transport models: the Boeing 747-400 and the Boeing C-17. Subjects included NASA, Air Force and commercial airline pilots. Results demonstrate the potential for improving handing qualities and significantly increased survivability rates under various simulated failure conditions.
Horsfall, I; Austin, S J; Bishop, W.
This paper describes the structural response of a current ceramic-faced composite armour system and a proposed structural armour system for aircraft use. The proposed structural ballistic armour system is shown to be capable of providing significant structural integrity even after ballistic impact whilst providing ballistic protection equivalent to an existing applique system. The addition of a carbon fibre reinforced plastic front panel to the existing ceramic faced composite armour system i...
Bryer, Paul; Buckles, Jon; Lemke, Paul; Peake, Kirk
This university design project concerns the Eagle RTS (Regional Transport System), a 66 passenger, twin turboprop aircraft with a range of 836 nautical miles. It will operate with a crew of two pilots and two flight attendents. This aircraft will employ the use of aluminum alloys and composite materials to reduce the aircraft weight and increase aerodynamic efficiency. The Eagle RTS will use narrow body aerodynamics with a canard configuration to improve performance. Leading edge technology will be used in the cockpit to improve flight handling and safety. The Eagle RTS propulsion system will consist of two turboprop engines with a total thrust of approximately 6300 pounds, 3150 pounds thrust per engine, for the cruise configuration. The engines will be mounted on the aft section of the aircraft to increase passenger safety in the event of a propeller failure. Aft mounted engines will also increase the overall efficiency of the aircraft by reducing the aircraft's drag. The Eagle RTS is projected to have a takeoff distance of approximately 4700 feet and a landing distance of 6100 feet. These distances will allow the Eagle RTS to land at the relatively short runways of regional airports.
Urnes, James, Sr.; Nguyen, Nhan; Ippolito, Corey; Totah, Joseph; Trinh, Khanh; Ting, Eric
Boeing and NASA are conducting a joint study program to design a wing flap system that will provide mission-adaptive lift and drag performance for future transport aircraft having light-weight, flexible wings. This Variable Camber Continuous Trailing Edge Flap (VCCTEF) system offers a lighter-weight lift control system having two performance objectives: (1) an efficient high lift capability for take-off and landing, and (2) reduction in cruise drag through control of the twist shape of the flexible wing. This control system during cruise will command varying flap settings along the span of the wing in order to establish an optimum wing twist for the current gross weight and cruise flight condition, and continue to change the wing twist as the aircraft changes gross weight and cruise conditions for each mission segment. Design weight of the flap control system is being minimized through use of light-weight shape memory alloy (SMA) actuation augmented with electric actuators. The VCCTEF program is developing better lift and drag performance of flexible wing transports with the further benefits of lighter-weight actuation and less drag using the variable camber shape of the flap.
Marshall, Douglas M; Hottman, Stephen B; Shappee, Eric; Most, Michael Thomas
Introduction to Unmanned Aircraft Systems is the editors' response to their unsuccessful search for suitable university-level textbooks on this subject. A collection of contributions from top experts, this book applies the depth of their expertise to identify and survey the fundamentals of unmanned aircraft system (UAS) operations. Written from a nonengineering civilian operational perspective, the book starts by detailing the history of UASs and then explores current technology and what is expected for the future. Covering all facets of UAS elements and operation-including an examination of s
Sabel, R.; Reffeltrath, P.A.; Jonkman, A.; Post, T.
As a participant in the three-nation partnership for development of the ANBCP-S for use in Helicopters, Transport Aircraft and Fast Jet, the Royal Netherlands Airforce (RNLAF) picked up the challenge to design a Filter- Blower-Unit (FBU). Major Command (MajCom) of the RNLAF set priority to develop a
Stephens, D. G.
Measured vibration and interior noise data are presented for a number of air and surface vehicles. Consideration is given to the importance of direction effects; of vehicle operations such as take-off, cruise, and landing; and of measurement location on the level and frequency of the measurements. Various physical measurement units or descriptors are used to quantify and compare the data. Results suggest the range of vibration and noise associated with a particular mode of transportation and illustrate the comparative levels in terms of each of the descriptors. Collectively, the results form a data base which may be useful in assessing the ride of existing or future systems relative to vehicles in current operation.
С. С. Юцкевич
Full Text Available Specifics of civil aviation modern transport aircraft fly-by-wire control systems are described. A comparison of the systems-level hardware and software, expressed through modes of guidance, provision of aircraft Airbus A-320, Boeing B-777, Tupolev Tu-214, Sukhoi Superjet SSJ-100 are carried out. The possibility of transition from mechanical control wiring to control through fly-by-wire system in the backup channel is shown.
Pornet, C.; Isikveren, A. T.
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
Researchers at NASA are investigating the potential for electric propulsion systems to revolutionize the design of aircraft from the small-scale general aviation sector to commuter and transport-class vehicles. Electric propulsion provides new degrees of design freedom that may enable opportunities for tightly coupled design and optimization of the propulsion system with the aircraft structure and control systems. This could lead to extraordinary reductions in ownership and operating costs, greenhouse gas emissions, and noise annoyance levels. We are building testbeds, high-fidelity aircraft simulations, and the first highly distributed electric inhabited flight test vehicle to begin to explore these opportunities.
A. S. Abufanas
Full Text Available The principles of constructing mathematical models of unmanned aircraft systems as complex systems consisting of a plurality ofsubsystems, each of which is considered as a system. In this case, the relationship between the subsystems are described by equations based on the topological graph theory, and for the preparation of component equations describing the dynamics of the subsystems is proposed to use differential equations discontinuous type based on systems theory of random structure.
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...
Nish, W A; Walsh, W F; Land, P; Swedenburg, M
The number of civilian air ambulance services operating in the United States has been steadily increasing. The quantity and sophistication of electronic equipment used during neonatal transport have also increased. All medical equipment generates some electromagnetic interference (EMI). Excessive EMI can interfere with any of an aircraft's electrical systems, including navigation and communications. The United States military has strict standards for maximum EMI in transport equipment. Over the past 15 years, approximately 70% of neonatal transport monitors, ventilators, and incubators have failed testing due to excessive EMI. As neonatal transport equipment becomes more sophisticated, EMI is increased, and there is greater potential for aircraft malfunction. The Federal Aviation Administration should develop civilian standards for acceptable EMI, civilian aircraft operators must be aware of the possible dangers of excessive EMI, and equipment which does not meet future FAA standards should not be purchased. PMID:2751593
The book addresses all major aspects to be considered for the design and operation of aircrafts within the entire transportation chain. It provides the basic information about the legal environment, which defines the basic requirements for aircraft design and aircraft operation. The interactions between airport, air traffic management and the airlines are described. The market forecast methods and the aircraft development process are explained to understand the very complex and risky business of an aircraft manufacturer. The principles of flight physics as basis for aircraft design are presented and linked to the operational and legal aspects of air transport including all environmental impacts. The book is written for graduate students as well as for engineers and experts, who are working in aerospace industry, at airports or in the domain of transport and logistics.
Magee, Todd E.; Fugal, Spencer R.; Fink, Lawrence E.; Adamson, Eric E.; Shaw, Stephen G.
completed as a precursor to the selection of the facilities used for validation testing. As facility schedules allowed, the propulsion testing was done at the NASA Glenn Research Center (GRC) 8 x 6-Foot wind tunnel, while boom and force testing was done at the NASA Ames Research Center (ARC) 9 x 7-Foot wind tunnel. During boom testing, a live balance was used for gathering force data. This report is broken down into nine sections. The first technical section (Section 2) covers the general scope of the Phase II activities, goals, a description of the design and testing efforts, and the project plan and schedule. Section 3 covers the details of the propulsion system concepts and design evolution. A series of short tests to evaluate the suitability of different wind tunnels for boom, propulsion, and force testing was also performed under the Phase 2 effort, with the results covered in Section 4. The propulsion integration testing is covered in Section 5 and the boom and force testing in Section 6. CFD comparisons and analyses are included in Section 7. Section 8 includes the conclusions and lessons learned.
The economic aspects of the STOL aircraft for short-haul air transportation are discussed. The study emphasized the potential market, the preferred operational concepts, the design characteristics, and the economic viability. Three central issues governing economic viability are as follows: (1) operator economics given the market, (2) the required transportation facilities, and (3) the external economic effects of a set of regional STOL transportation systems.
National Aeronautics and Space Administration — Development of an Aircraft Nodal Data Acquisition System (ANDAS) is proposed. The proposed methodology employs the development of a very thin (135m) hybrid...
National Aeronautics and Space Administration — Development of an Aircraft Nodal Data Acquisition System (ANDAS) based upon the short haul Zigbee networking standard is proposed. It employs a very thin (135 um)...
D. P. Coldbeck
Full Text Available In the 1980's the British aircraft industry changed its approach to the management of projects from a system where a project office would manage a project and rely on a series of specialist departments to support them to a more process oriented method, using systems engineering models, whose most outwardly visible signs were the introduction of multidisciplinary product teams. One of the problems with the old method was that the individual departments often had different priorities and projects would get uneven support. The change in the system was only made possible for complex designs by the electronic distribution of data giving instantaneous access to all involved in the project. In 1997 the Defence and Aerospace Foresight Panel emphasised the need for a system engineering approach if British industry was to remain competitive. The Royal Academy of Engineering recognised that the change in working practices also changed what was required of a chartered engineer and redefined their requirements in 1997 . The result of this is that engineering degree courses are now judged against new criteria with more emphasis placed on the relevance to industry rather than on purely academic content. At the University of Glasgow it was realized that the students ought to be made aware of current working practices and that there ought to be a review to ensure that the degrees give students the skills required by industry. It was decided to produce a one week introduction course in systems engineering for Masters of Engineering (MEng students to be taught by both university lecturers and practitioners from a range of companies in the aerospace industry with the hope of expanding the course into a module. The reaction of the students was favourable in terms of the content but it seems ironic that the main criticism was that there was not enough discussion involving the students. This paper briefly describes the individual teaching modules and discusses the
Lawing, P. L.; Pagel, L. L. (Inventor)
The system eliminates the necessity of shielding an aircraft airframe constructed of material such as aluminum. Cooling is accomplished by passing a coolant through the aircraft airframe, the coolant acting as a carrier to remove heat from the airframe. The coolant is circulated through a heat pump and a heat exchanger which together extract essentially all of the added heat from the coolant. The heat is transferred to the aircraft fuel system via the heat exchanger and the heat pump. The heat extracted from the coolant is utilized to power the heat pump. The heat pump has associated therewith power turbine mechanism which is also driven by the extracted heat. The power turbines are utilized to drive various aircraft subsystems, the compressor of the heat pump, and provide engine cooling.
The present invention concerns an air craft transporting container for nuclear fuels. A sealing container that seals a nuclear fuel container and constitutes a sealed boundary for the transporting container is incorporated in an inner container. Shock absorbers are filled for absorbing impact shock energy in the gap between the inner container and the sealing container. The inner container is incorporated with wooden impact shock absorbers being filled so that it is situated in a substantially central portion of an external container. Partitioning cylinders are disposed coaxially in the cylindrical layer filled with wooden impact shock absorbers at an intermediate portion between the outer and the inner containers. Further, a plurality of longitudinally intersecting partitioning disks are disposed each at a predetermined distance in right and left cylindrical wooden impact shock absorbing layers which are in contact with the end face of the inner container. Accordingly, the impact shock energy can be absorbed by the wooden impact shock absorbers efficiently by a plurality of the partitioning disks and the partitioning cylinders. (I.N.)
Bolonkin, Alexander; Gilyard, Glenn B.
Analytical benefits of variable-camber capability on subsonic transport aircraft are explored. Using aerodynamic performance models, including drag as a function of deflection angle for control surfaces of interest, optimal performance benefits of variable camber are calculated. Results demonstrate that if all wing trailing-edge surfaces are available for optimization, drag can be significantly reduced at most points within the flight envelope. The optimization approach developed and illustrated for flight uses variable camber for optimization of aerodynamic efficiency (maximizing the lift-to-drag ratio). Most transport aircraft have significant latent capability in this area. Wing camber control that can affect performance optimization for transport aircraft includes symmetric use of ailerons and flaps. In this paper, drag characteristics for aileron and flap deflections are computed based on analytical and wind-tunnel data. All calculations based on predictions for the subject aircraft and the optimal surface deflection are obtained by simple interpolation for given conditions. An algorithm is also presented for computation of optimal surface deflection for given conditions. Benefits of variable camber for a transport configuration using a simple trailing-edge control surface system can approach more than 10 percent, especially for nonstandard flight conditions. In the cruise regime, the benefit is 1-3 percent.
Harvey, W. Don; Foreman, Brent
This report provides updated information on the current market and operating environment and identifies interlinking technical possibilities for competitive future commuter-type transport aircraft. The conclusions on the market and operating environment indicate that the regional airlines are moving toward more modern and effective fleets with greater passenger capacity and comfort, reduced noise levels, increased speed, and longer range. This direction leads to a nearly 'seamless' service and continued code-sharing agreements with the major carriers. Whereas the benefits from individual technologies may be small, the overall integration in existing and new aircraft designs can produce improvements in direct operating cost and competitiveness. Production costs are identified as being equally important as pure technical advances.
Wing joint design is one of the most critical areas in aircraft structures. Efficient and damage tolerant wing-fuselage integration structure, applicable to the next generation of transport aircraft, will facilitate the realisation of the benefits offered by new aircraft concepts. The Blended Wing Body (BWB) aircraft concept represents a potential revolution in subsonic transport efficiency for large airplanes. Studies have shown the BWB to be superior to conventional airframes...
Valenzuela Arroyo, Marta
The goal of this project is to design and implement a mission manager for unmanned aircraft systems. The mission manager will work under the USAL architecture designed by the ICARUS UAV group at the EPSC. The student will be able to learn programming skills, working with a group, and research.
White, Henry J.; Brownjohn, Nick; Baptista, João;
Achieving affordable high speed fiber optic communication networks for airplane systems has proved to be challenging. In this paper we describe a summary of the EU Framework 7 project DAPHNE (Developing Aircraft Photonic Networks). DAPHNE aimed to exploit photonic technology from terrestrial...
Beltramo, M. N.; Morris, M. A.; Anderson, J. L.
A model comprised of system level weight and cost estimating relationships for transport aircraft is presented. In order to determine the production cost of future aircraft its weight is first estimated based on performance parameters, and then the cost is estimated as a function of weight. For initial evaluation CERs were applied to actual system weights of six aircraft (3 military and 3 commercial) with mean empty weights ranging from 30,000 to 300,000 lb. The resulting cost estimates were compared with actual costs. The average absolute error was only 4.3%. Then the model was applied to five aircraft still in the design phase (Boeing 757, 767 and 777, and BAC HS146-100 and HS146-200). While the estimates for the 757 and 767 are within 2 to 3 percent of their assumed break-even costs, it is recognized that these are very sensitive to the validity of the estimated weights, inflation factor, the amount assumed for nonrecurring costs, etc., and it is suggested that the model may be used in conjunction with other information such as RDT&E cost estimates and market forecasts. The model will help NASA evaluate new technologies and production costs of future aircraft.
Cunningham, Kevin; Foster, John V.; Morelli, Eugene A.; Murch, Austin M.
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.
... of provisions pertaining to integration of unmanned aircraft systems (UAS) into the National Airspace... Federal Aviation Administration 14 CFR Part 91 Unmanned Aircraft System Test Site Program AGENCY: Federal... be levied on the Unmanned Aircraft Systems Test Site operators, but prior to the close of the...
National Aeronautics and Space Administration — There is an increasing need to fly Unmanned Aircraft Systems (UAS) in the National Airspace System (NAS) to perform missions of vital importance to national...
Sotack, Robert A.; Chowdhry, Rajiv S.; Buttrill, Carey S.
The mathematical model and associated code to simulate a high speed civil transport aircraft - the Boeing Reference H configuration - are described. The simulation was constructed in support of advanced control law research. In addition to providing time histories of the dynamic response, the code includes the capabilities for calculating trim solutions and for generating linear models. The simulation relies on the nonlinear, six-degree-of-freedom equations which govern the motion of a rigid aircraft in atmospheric flight. The 1962 Standard Atmosphere Tables are used along with a turbulence model to simulate the Earth atmosphere. The aircraft model has three parts - an aerodynamic model, an engine model, and a mass model. These models use the data from the Boeing Reference H cycle 1 simulation data base. Models for the actuator dynamics, landing gear, and flight control system are not included in this aircraft model. Dynamic responses generated by the nonlinear simulation are presented and compared with results generated from alternate simulations at Boeing Commercial Aircraft Company and NASA Langley Research Center. Also, dynamic responses generated using linear models are presented and compared with dynamic responses generated using the nonlinear simulation.
Coogan, J. J.
Modifications were designed for the B-737-100 Research Aircraft autobrake system hardware of the Advanced Transport Operating Systems (ATOPS) Program at Langley Research Center. These modifications will allow the on-board flight control computer to control the aircraft deceleration after landing to a continuously variable level for the purpose of executing automatic high speed turn-offs from the runway. A bread board version of the proposed modifications was built and tested in simulated stopping conditions. Test results, for various aircraft weights, turnoff speed, winds, and runway conditions show that the turnoff speeds are achieved generally with errors less than 1 ft/sec.
NASA's Small Business Innovation Research (SBIR) and Small Business Technology Transfer (STTR) programs, as well as a number of Agency innovations, have helped Duluth, Minnesota-based Cirrus Design Corporation become one of the world's leading manufacturers of general aviation aircraft. SBIRs with Langley Research Center provided the company with cost-effective composite airframe manufacturing methods, while crashworthiness testing at the Center increased the safety of its airplanes. Other NASA-derived technologies on Cirrus SR20 and SR22 aircraft include synthetic vision systems that help pilots navigate and full-plane parachutes that have saved the lives of more than 30 Cirrus pilots and passengers to date. Today, the SR22 is the world's top-selling Federal Aviation Administration (FAA)-certified single-engine airplane.
Krus, Petter; Braun, Robert; Nordin, Peter; Eriksson, Björn
Developments in computational hardware and simulation software have come to a point where it is possible to use whole mission simulation in a framework for conceptual/preliminary design. This paper is about the implementation of full system simulation software for conceptual/preliminary aircraft design. It is based on the new Hopsan NG simulation package, developed at the Linköping University. The Hopsan NG software is implemented in C++. Hopsan NG is the first simulation software that has su...
Full Text Available As the aircraft industry is moving towards the all electric and More Electric Aircraft (MEA; is the future trend in adopting single power type for driving the non-propulsive aircraft systems; i.e. is the electrical power. The trend in the aircraft industry is to replace hydraulic and pneumatic systems with electrical systems achieving more comfort and monitoring features. The structure of MEA distribution system improves aircraft maintainability, reliability, flight safety and efficiency. Moreover, MEA reduces the emissions of air pollutant gases from aircrafts, which can contribute in significantly solving some of the problems of climate change. However, the MEA puts some challenges on the aircraft electrical system, both in the amount of the required power and the processing and management of this power. MEA electrical distribution systems are mainly in the form of multi-converter power electronic system.
Zhao, Xin; Guerrero, Josep M.; Wu, Xiaohao
In recent years, the electrical power capacity is increasing rapidly in more electric aircraft (MEA), since the conventional mechanical, hydraulic and pneumatic energy systems are partly replaced by electrical power system. As a consequence, capacity and complexity of aircraft electric power...... systems (EPS) will increase dramatically and more advanced aircraft EPSs need to be developed. This paper gives a brief description of the constant frequency (CF) EPS, variable frequency (VF) EPS and advanced high voltage (HV) EPS. Power electronics in the three EPS is overviewed. Keywords: Aircraft Power...... System, More Electric Aircraft, Constant Frequency, Variable Frequency, High Voltage....
... 14 Aeronautics and Space 3 2010-01-01 2010-01-01 false Wet leasing of aircraft and other arrangements for transportation by air. 119.53 Section 119.53 Aeronautics and Space FEDERAL AVIATION... Chapter § 119.53 Wet leasing of aircraft and other arrangements for transportation by air. (a)...
Rizzi, Stephen A.; Christian, Andrew
The NASA Environmentally Responsible Aviation project has been successful in developing and demonstrating technologies for integrated aircraft systems that can simultaneously meet aggressive goals for fuel burn, noise and emissions. Some of the resulting systems substantially differ from the familiar tube and wing designs constituting the current civil transport fleet. This study attempts to explore whether or not the effective perceived noise level metric used in the NASA noise goal accurately reflects human subject response across the range of vehicles considered. Further, it seeks to determine, in a quantitative manner, if the sounds associated with the advanced aircraft are more or less preferable to the reference vehicles beyond any differences revealed by the metric. These explorations are made through psychoacoustic tests in a controlled laboratory environment using simulated stimuli developed from auralizations of selected vehicles based on systems noise assessments.
Petley, Dennis H.; Jones, Stuart C.; Dziedzic, William M.
A computer program has been written to analyze cooling systems of hypersonic aircraft. This computer program called NASP/SINDA is written into the SINDA'85 command structure and uses the SINDA'85 finite difference subroutines. Both internal fluid flow and heat transfer must be analyzed, because increased heating causes a decrease in the flow of the coolant. Also local hot spots will cause a redistribution of the coolant in the system. Both steady state and transient analyses have been performed. Details of empirical correlations are presented. Results for two cooling system applications are given.
Nengjian Wang; Hongbo Liu; Wanhui Yang
An aircraft tractor plays a significant role as a kind of important marine transport and support equipment.It's necessary to study its controlling and manoeuvring stability to improve operation efficiency.A virtual prototyping model of the tractor-aircraft system based on Lagrange's equation of the first kind with Lagrange mutipliers was established in this paper.According to the towing characteristics,a path-tracking controller using fuzzy logic theory was designed.Direction control herein was carried out through a compensatory tracking approach.Interactive co-simulation was performed to validate the path-tracking behavior in closed-loop.Simulation results indicated that the tractor followed the reference courses precisely on a flat ground.
Hange, Craig E.
This presentation will be given at the AIAA Electric Hybrid-Electric Power Propulsion Workshop on July 29, 2016. The workshop is being held so the AIAA can determine how it can support the introduction of electric aircraft into the aerospace industry. This presentation will address the needs of the community within the industry that advocates the use of powered-lift as important new technologies for future aircraft and air transportation systems. As the current chairman of the VSTOL Aircraft Systems Technical Committee, I will be presenting generalized descriptions of the past research in developing powered-lift and generalized observations on how electric and hybrid-electric propulsion may provide advances in the powered-lift field.
This report addresses the author’s Group Design Project (GDP) and Individual Research Project (IRP). The IRP is discussed primarily herein, presenting the actuation technology for the Flight Control System (FCS) on civil aircraft. Actuation technology is one of the key technologies for next generation More Electric Aircraft (MEA) and All Electric Aircraft (AEA); it is also an important input for the preliminary design of the Flying Crane, the aircraft designed in the author’s G...
Park, Pangun; Khadilkar, Harshad Dilip; Balakrishnan, Hamsa; Tomlin, Claire J.
This paper addresses the design of a secure and fault-tolerant air transportation system in the presence of attempts to disrupt the system through the satellite-based navigation system. Adversarial aircraft are assumed to transmit incorrect position and intent information, potentially leading to violations of separation requirements among aircraft. We propose a framework for the identification of adversaries and malicious aircraft, and then for air traffic control in the presence of such deli...
Nguyen, Truong X.; Dudley, Kenneth L.; Scearce, Stephen A.; Ely, Jay J.; Richardson, Robert E.; Hatfield, Michael O.
An investigation was performed to study the potential for radio frequency (RF) power radiated from Portable Electronic Devices (PEDs) to create an arcing/sparking event within the fuel tank of a large transport aircraft. This paper describes the experimental methods used for measuring RF coupling to the fuel tank and Fuel Quantity Indication System (FQIS) wiring from PED sources located in the passenger cabin. To allow comparison of voltage/current data obtained in a laboratory chamber FQIS installation to an actual aircraft FQIS installation, aircraft fuel tank RF reverberation characteristics were also measured. Results from the measurements, along with a survey of threats from typical intentional transmitting PEDs are presented. The resulting worst-case power coupled onto fuel tank FQIS wiring is derived. The same approach can be applied to measure RF coupling into various other aircraft systems.
The new 1996 IAEA regulation for the transportation of radioactive material states a 90 m/s drop test on unyielding surface for packages transported by air. This figure originates from a statistical analysis on civil aircraft accident during the period 1975 to 1985. A review on the 1983-1989 period demonstrates comparable velocity with a less stringent definition of accident. The statistical analyses are combined with the hardness of the fly-over ground and the impact angle to generate probabilities curves giving the occurrence of a mechanical stress overtaking the drop test velocity. The following steps were carried out: statistical analysis of the accident database from the ICOA (International Civil Aviation Organisation) to appreciate the accident characteristics with special attention to the impact velocity and angle. Modelling of the impact speed in each phase of flight (Take off, Climbing, Cruise, Approach and Landing), in order to evaluate the probability of occurrence of a given crash impact for different flight configurations. Qualitative analysis of recorder failures available in France. As the statistical analysis is based on the available impact speed, a bias can be introduced if major crashes are neglected. In this respect, the qualitative analysis should give some elements to characterize the relationship between the non-availability of the information recorded on the black box and the severity of the accident. (author)
The study of naturally-occurring radiation and its associated risk is one of the preoccupations of bodies responsible for radiation protection. Cosmic particle flux is significantly higher on board aircraft that at ground level. Furthermore, its intensity depends on solar activity and eruptions. Due to their professional activity, flight crews and frequent flyers may receive an annual dose of some milli-sieverts. This is why the European directive adopted in 1996 requires the aircraft operators to assess the dose and to inform their flight crews about the risk. The effective dose is to be estimated using various experimental and calculation means. In France, the computerized system for flight assessment of exposure to cosmic radiation in air transport (SIEVERT) is delivered to airlines for assisting them in the application of the European directive. This dose assessment tool was developed by the French General Directorate of Civil Aviation (DGAC) and partners: the Institute for Radiation Protection and Nuclear Safety (IRSN), the Paris Observatory and the French Institute for Polar Research - Paul-Emile Victor (IPEV). This professional service is available on an Internet server accessible to companies with a public section. The system provides doses that consider the routes flown by aircraft Various results obtained are presented. (authors)
The more-electric aircraft concept is a major trend in aircraft electrical power system engineering and results in an increase in electrical loads based on power electronic converters and motor drive systems. Unfortunately, power electronic driven loads often behave as constant power loads having the small-signal negative impedance that can significantly degrade the power system stability margin. Therefore, the stability issue of aircraft power systems is of great importance. The research of ...
Gerren, Donna S.
A study has been conducted to determine the capability to control a very large transport airplane with engine thrust. This study consisted of the design of an 800-passenger airplane with a range of 5000 nautical miles design and evaluation of a flight control system, and design and piloted simulation evaluation of a thrust-only backup flight control system. Location of the four wing-mounted engines was varied to optimize the propulsive control capability, and the time constant of the engine response was studied. The goal was to provide level 1 flying qualities. The engine location and engine time constant did not have a large effect on the control capability. The airplane design did meet level 1 flying qualities based on frequencies, damping ratios, and time constants in the longitudinal and lateral-directional modes. Project pilots consistently rated the flying qualities as either level 1 or level 2 based on Cooper-Harper ratings. However, because of the limited control forces and moments, the airplane design fell short of meeting the time required to achieve a 30 deg bank and the time required to respond a control input.
Mekel, R.; Nachmias, S.
A learning control system and its utilization as a flight control system for F-8 Digital Fly-By-Wire (DFBW) research aircraft is studied. The system has the ability to adjust a gain schedule to account for changing plant characteristics and to improve its performance and the plant's performance in the course of its own operation. Three subsystems are detailed: (1) the information acquisition subsystem which identifies the plant's parameters at a given operating condition; (2) the learning algorithm subsystem which relates the identified parameters to predetermined analytical expressions describing the behavior of the parameters over a range of operating conditions; and (3) the memory and control process subsystem which consists of the collection of updated coefficients (memory) and the derived control laws. Simulation experiments indicate that the learning control system is effective in compensating for parameter variations caused by changes in flight conditions.
Zhao, Xin; Guerrero, Josep M.; Wu, Xiaohao
In recent years, the electrical power capacity is increasing rapidly in more electric aircraft (MEA), since the conventional mechanical, hydraulic and pneumatic energy systems are partly replaced by electrical power system. As a consequence, capacity and complexity of aircraft electric power systems (EPS) will increase dramatically and more advanced aircraft EPSs need to be developed. This paper gives a brief description of the constant frequency (CF) EPS, variable frequency (VF) EPS and adva...
Adachi, Fumiyuki; Miyazaki, Hiroyuki; Endo, Chikara
If a large scale disaster similar to the Great East Japan Earthquake 2011 happens, some areas may be isolated from the communications network. Recently, unmanned aircraft system (UAS) based wireless relay communication has been attracting much attention since it is able to quickly re-establish the connection between isolated areas and the network. However, the channel between ground station (GS) and unmanned aircraft (UA) is unreliable due to UA's swing motion and as consequence, the relay communication quality degrades. In this paper, we introduce space-time block coded (STBC) amplify-and-forward (AF) relay for UAS based wireless relay communication to improve relay communication quality. A group of UAs forms single frequency network (SFN) to perform STBC-AF cooperative relay. In STBC-AF relay, only conjugate operation, block exchange and amplifying are required at UAs. Therefore, STBC-AF relay improves the relay communication quality while alleviating the complexity problem at UAs. It is shown by computer simulation that STBC-AF relay can achieve better throughput performance than conventional AF relay.
... can be found in the Federal Register published on April 11, 2000 (65 FR 19477-19478), as well as at... Federal Aviation Administration 14 CFR Part 91 Unmanned Aircraft System Test Sites AGENCY: Federal... test ranges/sites to integrate unmanned aircraft systems (UAS) into the National Airspace System...
National Aeronautics and Space Administration — Current and planned transport aircraft designs are making more use of fly-by-wire technology, allowing an unprecedented design space for control laws, including...
Hibbs, Bart D.; Lissaman, Peter B. S.; Morgan, Walter R.; Radkey, Robert L.
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.
Nielsen, Peter Vilhelm; Zhang, Chen; Wojcik, Kamil;
Traditionally, air is supplied to the aircraft cabin either by individual nozzles or by supply slots. The air is expected to be fully mixed in the cabin, and the system is considered to be a mixing ventilation system. This paper will provide measurements on the mixing flow in an aircraft cabin...
Maintenance and support are basic elements to realize the effectiveness of aircraft. For basic analysis of the characteristics of an aircraft maintenance and support system, a simulation method is presented in this paper, and the structure and realization ofthe simulation system is discussed.
Thomas, Russell H. (Inventor); Czech, Michael J. (Inventor); Elkoby, Ronen (Inventor)
The aircraft exhaust engine nozzle system includes a fan nozzle to receive a fan flow from a fan disposed adjacent to an engine disposed above an airframe surface of the aircraft, a core nozzle disposed within the fan nozzle and receiving an engine core flow, and a pylon structure connected to the core nozzle and structurally attached with the airframe surface to secure the engine to the aircraft.
Delgado, Francisco J.; White, Janis; Abernathy, Michael F.
This paper describes a new approach to situation awareness that combines video sensor technology and synthetic vision technology in a unique fashion to create a hybrid vision system. Our implementation of the technology, called "SmartCam3D" (SCS3D) has been flight tested by both NASA and the Department of Defense with excellent results. This paper details its development and flight test results. Windshields and windows add considerable weight and risk to vehicle design, and because of this, many future vehicles will employ a windowless cockpit design. This windowless cockpit design philosophy prompted us to look at what would be required to develop a system that provides crewmembers and operations personnel an appropriate level of situation awareness. The system created to date provides a real-time 3D perspective display that can be used during all-weather and visibility conditions. While the advantages of a synthetic vision only system are considerable, the major disadvantage of such a system is that it displays the synthetic scene created using "static" data acquired by an aircraft or satellite at some point in the past. The SCS3D system we are presenting in this paper is a hybrid synthetic vision system that fuses live video stream information with a computer generated synthetic scene. This hybrid system can display a dynamic, real-time scene of a region of interest, enriched by information from a synthetic environment system, see figure 1. The SCS3D system has been flight tested on several X-38 flight tests performed over the last several years and on an ARMY Unmanned Aerial Vehicle (UAV) ground control station earlier this year. Additional testing using an assortment of UAV ground control stations and UAV simulators from the Army and Air Force will be conducted later this year. We are also identifying other NASA programs that would benefit from the use of this technology.
The cabin environment of a commercial aircraft, including cabin layout and the quality of air supply, is crucial to the airline operators. These aspects directly affect the passengers’ experience and willing to travel. This aim of this thesis is to design the cabin layout for flying wing aircraft as part of cabin environment work, followed by the air quality work, which is to understand what effect the ECS can have in terms of cabin air contamination. The project, initially, focuses on the...
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...
Burken, John J.; Frost, Susan A.; Taylor, Brian R.
When designing control laws for systems with constraints added to the tracking performance, control allocation methods can be utilized. Control allocations methods are used when there are more command inputs than controlled variables. Constraints that require allocators are such task as; surface saturation limits, structural load limits, drag reduction constraints or actuator failures. Most transport aircraft have many actuated surfaces compared to the three controlled variables (such as angle of attack, roll rate & angle of side slip). To distribute the control effort among the redundant set of actuators a fixed mixer approach can be utilized or online control allocation techniques. The benefit of an online allocator is that constraints can be considered in the design whereas the fixed mixer cannot. However, an online control allocator mixer has a disadvantage of not guaranteeing a surface schedule, which can then produce ill defined loads on the aircraft. The load uncertainty and complexity has prevented some controller designs from using advanced allocation techniques. This paper considers actuator redundancy management for a class of over actuated systems with real-time structural load limits using linear quadratic tracking applied to the generic transport model. A roll maneuver example of an artificial load limit constraint is shown and compared to the same no load limitation maneuver.
Skoog, Mark (Inventor); Hook, Loyd (Inventor); McWherter, Shaun (Inventor); Willhite, Jaimie (Inventor)
The invention is a system and method of compressing a DTM to be used in an Auto-GCAS system using a semi-regular geometric compression algorithm. In general, the invention operates by first selecting the boundaries of the three dimensional map to be compressed and dividing the three dimensional map data into regular areas. Next, a type of free-edged, flat geometric surface is selected which will be used to approximate terrain data of the three dimensional map data. The flat geometric surface is used to approximate terrain data for each regular area. The approximations are checked to determine if they fall within selected tolerances. If the approximation for a specific regular area is within specified tolerance, the data is saved for that specific regular area. If the approximation for a specific area falls outside the specified tolerances, the regular area is divided and a flat geometric surface approximation is made for each of the divided areas. This process is recursively repeated until all of the regular areas are approximated by flat geometric surfaces. Finally, the compressed three dimensional map data is provided to the automatic ground collision system for an aircraft.
National Aeronautics and Space Administration — Aircraft powered by hydrogen power plants or gas turbines driving electric generators connected to distributed electric motors for propulsion have the potential to...
This Transportation System Requirements Document (Trans-SRD) describes the functions to be performed by and the technical requirements for the Transportation System to transport spent nuclear fuel (SNF) and high-level radioactive waste (HLW) from Purchaser and Producer sites to a Civilian Radioactive Waste Management System (CRWMS) site, and between CRWMS sites. The purpose of this document is to define the system-level requirements for Transportation consistent with the CRWMS Requirement Document (CRD). These requirements include design and operations requirements to the extent they impact on the development of the physical segments of Transportation. The document also presents an overall description of Transportation, its functions, its segments, and the requirements allocated to the segments and the system-level interfaces with Transportation. The interface identification and description are published in the CRWMS Interface Specification.
This Transportation System Requirements Document (Trans-SRD) describes the functions to be performed by and the technical requirements for the Transportation System to transport spent nuclear fuel (SNF) and high-level radioactive waste (HLW) from Purchaser and Producer sites to a Civilian Radioactive Waste Management System (CRWMS) site, and between CRWMS sites. The purpose of this document is to define the system-level requirements for Transportation consistent with the CRWMS Requirement Document (CRD). These requirements include design and operations requirements to the extent they impact on the development of the physical segments of Transportation. The document also presents an overall description of Transportation, its functions, its segments, and the requirements allocated to the segments and the system-level interfaces with Transportation. The interface identification and description are published in the CRWMS Interface Specification
It is possible to get a crude estimate of wind speed and direction while driving a car at night in the rain, with the motion of the raindrop reflections in the headlights providing clues about the wind. The clues are difficult to interpret, though, because of the relative motions of ground, car, air, and raindrops. More subtle interpretation is possible if the rain is replaced by fog, because the tiny droplets would follow the swirling currents of air around an illuminated object, like, for example, a walking pedestrian. Microscopic particles in the air (aerosols) are better for helping make assessments of the wind, and reflective air molecules are best of all, providing the most refined measurements. It takes a bright light to penetrate fog, so it is easy to understand how other factors, like replacing the headlights with the intensity of a searchlight, can be advantageous. This is the basic principle behind a lidar system. While a radar system transmits a pulse of radiofrequency energy and interprets the received reflections, a lidar system works in a similar fashion, substituting a near-optical laser pulse. The technique allows the measurement of relative positions and velocities between the transmitter and the air, which allows measurements of relative wind and of air temperature (because temperature is associated with high-frequency random motions on a molecular level). NASA, as well as the National Oceanic and Atmospheric Administration (NOAA), have interests in this advanced lidar technology, as much of their explorative research requires the ability to measure winds and turbulent regions within the atmosphere. Lidar also shows promise for providing warning of turbulent regions within the National Airspace System to allow commercial aircraft to avoid encounters with turbulence and thereby increase the safety of the traveling public. Both agencies currently employ lidar and optical sensing for a variety of weather-related research projects, such as analyzing
Kochan, Kay; Sachau, Delf; Breitbach, Harald
The active noise control (ANC) method is based on the superposition of a disturbance noise field with a second anti-noise field using loudspeakers and error microphones. This method can be used to reduce the noise level inside the cabin of a propeller aircraft. However, during the design process of the ANC system, extensive measurements of transfer functions are necessary to optimize the loudspeaker and microphone positions. Sometimes, the transducer positions have to be tailored according to the optimization results to achieve a sufficient noise reduction. The purpose of this paper is to introduce a controller design method for such narrow band ANC systems. The method can be seen as an extension of common transducer placement optimization procedures. In the presented method, individual weighting parameters for the loudspeakers and microphones are used. With this procedure, the tailoring of the transducer positions is replaced by adjustment of controller parameters. Moreover, the ANC system will be robust because of the fact that the uncertainties are considered during the optimization of the controller parameters. The paper describes the necessary theoretic background for the method and demonstrates the efficiency in an acoustical mock-up of a military transport aircraft. PMID:21568404
In aircraft development, it is crucial to understand and evaluate behavior, performance, safety and other aspects of the systems before and after they are physically available for testing. Simulation models are used to gain knowledge in order to make decisions at all development stages. Modeling and simulation (M&S) in aircraft system development, for example of fuel, hydraulic and electrical power systems, is today an important part of the design process. Through M&S a problem in a f...
... ratings at the airline transport pilot certification level). 61.63 Section 61.63 Aeronautics and Space... aircraft ratings (other than for ratings at the airline transport pilot certification level). (a) General. For an additional aircraft rating on a pilot certificate, other than for an airline transport...
... Transportation To Investigate Certain Aircraft Accidents Appendix to Part 800 Transportation Other Regulations... the Department of Transportation To Investigate Certain Aircraft Accidents (a) Acting pursuant to the... Safety Board Act of 1974, and as set forth below to investigate the facts, conditions, and...
Aerodynamic design of transport aircraft has been steadily improved over past several decades, to the point where today highly-detailed shape control is needed to achieve further improvements. Aircraft manufacturers are therefore increasingly looking into formal optimization methods, driving high-fidelity CFD analysis of finely-parametrized candidate designs. We present an adjoint gradient-based approach for maximizing the aerodynamic performance index relevant to cruise-climb mission segment...
National Aeronautics and Space Administration — Electrical power systems play a critical role in spacecraft and aircraft, and they exhibit a rich variety of failure modes. This paper discusses electrical power...
Reck, G. M.
Possible changes in fuel properties are identified based on current trends and projections. The effect of those changes with respect to the aircraft fuel system are examined and some technological approaches to utilizing those fuels are described.
National Aeronautics and Space Administration — Phase 1 has seen the development of a revolutionary new type of sensor for making carbon dioxide (CO2) measurements from small Unmanned Aircraft Systems (UAS) and...
Westenberger, A.; Bleil, J.; Arendt, M. [Airbus Deutschland GmbH, Hamburg (Germany)
The intention of using a highly integrated component using on fuel cell technology installed on board of large commercial passenger aircraft for the generation of onboard power for the systems demand during an entire aircraft mission was subject of several studies. The results of these studies have been based on the simulation of the whole system in the context of an aircraft system environment. In front of the work stood the analyses of different fuel cell technologies and the analyses of the aircraft system environment. Today onboard power is provided on ground by an APU and in flight by the main engines. In order to compare fuel cell technology with the today's usual gas turbine operational characteristics have been analysed. A second analysis was devoted to the system demand for typical aircraft categories. The MEA system concept was supposed in all cases. The favourable concept represented an aircraft propelled by conventional engines with starter generator units, providing AC electrical power, covering in total proximately half of the power demand and a component based on fuel cell technology. This component provided electrical DC power, clean potable water, thermal energy at 180 degrees Celsius and nitrogen enriched air for fire suppression and fire extinguishing agent. In opposite of a usual gas turbine based APU, this new unit was operated as the primary power system. (orig.)
The evaluation indexes system of aircraft survivability is constructed for the first time from three aspects: susceptibility, vulnerability and combat resilience; the bargaining weight method is proposed to determine the weights of the indexes and evaluate aircraft survivability. The bargaining weight method brings different opinions into accord under the constraint of minimum loss, it can overcome the partial subjectivity in determining weights and evaluation, and has objectivity. The example testifies rationality and feasibility of the evaluation system.
Overø, Helene Martine; Larsen, Allan; Røpke, Stefan
The Danish innovation project entitled “Intelligent Freight Transport Systems” aims at developing prototype systems integrating public intelligent transport systems (ITS) with the technology in vehicles and equipment as well as the IT-systems at various transport companies. The objective...... is to enhance the efficiency and lower the environmental impact in freight transport. In this paper, a pilot project involving real-time waste collection at a Danish waste collection company is described, and a solution approach is proposed. The problem corresponds to the dynamic version of the waste collection...
Hayhurst, Kelly J.; Maddalon, Jeffrey M.; Miner, Paul S.; Szatkowski, George N.; Ulrey, Michael L.; DeWalt, Michael P.; Spitzer, Cary R.
The use of unmanned aircraft in national airspace has been characterized as the next great step forward in the evolution of civil aviation. To make routine and safe operation of these aircraft a reality, a number of technological and regulatory challenges must be overcome. This report discusses some of the regulatory challenges with respect to deriving safety and reliability requirements for unmanned aircraft. In particular, definitions of hazards and their classification are discussed and applied to a preliminary functional hazard assessment of a generic unmanned system.
Liou, Meng-Sing; Stewart, Mark E.; Suresh, Ambady; Owen, A. Karl
This report outlines the Space Transportation Propulsion Systems for the NPSS (Numerical Propulsion System Simulation) program. Topics include: 1) a review of Engine/Inlet Coupling Work; 2) Background/Organization of Space Transportation Initiative; 3) Synergy between High Performance Computing and Communications Program (HPCCP) and Advanced Space Transportation Program (ASTP); 4) Status of Space Transportation Effort, including planned deliverables for FY01-FY06, FY00 accomplishments (HPCCP Funded) and FY01 Major Milestones (HPCCP and ASTP); and 5) a review current technical efforts, including a review of the Rocket-Based Combined-Cycle (RBCC), Scope of Work, RBCC Concept Aerodynamic Analysis and RBCC Concept Multidisciplinary Analysis.
Velders, G.J.M.; Heijboer, L. C.; Kelder, H.
A three-dimensional off-line tracer transport model coupled to the ECMWF analyses has been used to study the transport of trace gases in the atmosphere. The model gives a reasonable description of their general transport in the atmosphere. The simulation of the transport of aircraft emissions (as NOx) has been studied as well as the transport of passive tracers injected at different altitudes in the North Atlantic flight corridor. A large zonal variation in the NO
Bridgelall, Raj; Rafert, J. Bruce; Tolliver, Denver
The global transportation system is massive, open, and dynamic. Existing performance and condition assessments of the complex interacting networks of roadways, bridges, railroads, pipelines, waterways, airways, and intermodal ports are expensive. Hyperspectral imaging is an emerging remote sensing technique for the non-destructive evaluation of multimodal transportation infrastructure. Unlike panchromatic, color, and infrared imaging, each layer of a hyperspectral image pixel records reflectance intensity from one of dozens or hundreds of relatively narrow wavelength bands that span a broad range of the electromagnetic spectrum. Hence, every pixel of a hyperspectral scene provides a unique spectral signature that offers new opportunities for informed decision-making in transportation systems development, operations, and maintenance. Spaceborne systems capture images of vast areas in a short period but provide lower spatial resolution than airborne systems. Practitioners use manned aircraft to achieve higher spatial and spectral resolution, but at the price of custom missions and narrow focus. The rapid size and cost reduction of unmanned aircraft systems promise a third alternative that offers hybrid benefits at affordable prices by conducting multiple parallel missions. This research formulates a theoretical framework for a pushbroom type of hyperspectral imaging system on each type of data acquisition platform. The study then applies the framework to assess the relative potential utility of hyperspectral imaging for previously proposed remote sensing applications in transportation. The authors also introduce and suggest new potential applications of hyperspectral imaging in transportation asset management, network performance evaluation, and risk assessments to enable effective and objective decision- and policy-making.
Tischler, Mark B.
System-identification methods compose a mathematical model, or series of models, from measurements of inputs and outputs of dynamic systems. The extracted models allow the characterization of the response of the overall aircraft or component subsystem behavior, such as actuators and on-board signal processing algorithms. This paper discusses the use of frequency-domain system-identification methods for the development and integration of aircraft flight-control systems. The extraction and analysis of models of varying complexity from nonparametric frequency-responses to transfer-functions and high-order state-space representations is illustrated using the Comprehensive Identification from FrEquency Responses (CIFER) system-identification facility. Results are presented for test data of numerous flight and simulation programs at the Ames Research Center including rotorcraft, fixed-wing aircraft, advanced short takeoff and vertical landing (ASTOVL), vertical/short takeoff and landing (V/STOL), tiltrotor aircraft, and rotor experiments in the wind tunnel. Excellent system characterization and dynamic response prediction is achieved for this wide class of systems. Examples illustrate the role of system-identification technology in providing an integrated flow of dynamic response data around the entire life-cycle of aircraft development from initial specifications, through simulation and bench testing, and into flight-test optimization.
Price, D. B.; Gracey, C.
The Theoretical Mechanics Branch has as one of its long-range goals to work toward solving real-time trajectory optimization problems on board an aircraft. This is a generic problem that has application to all aspects of aviation from general aviation through commercial to military. Overall interest is in the generic problem, but specific problems to achieve concrete results are examined. The problem is to develop control laws that generate approximately optimal trajectories with respect to some criteria such as minimum time, minimum fuel, or some combination of the two. These laws must be simple enough to be implemented on a computer that is flown on board an aircraft, which implies a major simplification from the two point boundary value problem generated by a standard trajectory optimization problem. In addition, the control laws allow for changes in end conditions during the flight, and changes in weather along a planned flight path. Therefore, a feedback control law that generates commands based on the current state rather than a precomputed open-loop control law is desired. This requirement, along with the need for order reduction, argues for the application of singular perturbation techniques.
Benoit, Michael J.
The Mercer Engineering Research Center (MERC), under contract to the United States Air Force (USAF) since 1989, has been actively involved in providing the Warner Robins Air Logistics Center (WR-ALC) with a robotic workcell designed to perform rework automated defastening and hole location/transfer operations on F-15 wings. This paper describes the activities required to develop and implement this workcell, known as the Automated Aircraft Rework System (AARS). AARS is scheduled to be completely installed and in operation at WR-ALC by September 1994.
Ustijana RECHKOSKA SHIKOSKA
Full Text Available The most critical operation for an aircraft to perform is landing. Even in bad weather, more specifically poor visibility, landing becomes virtually impossible of instrument guidance to aid the pilot. The more extreme case occurs when the visibility is near zero and the pilot cannot land the plane manually. This situation requires an automatic landing or precision approach to be performed by the aircraft flight control system in conjunction with a landing/guidance system. This type of guidance has been provided by the integration of the Global Positioning System (GPS and Inertial Navigation System (INS.
Douglass, Anne R.; Rood, Richard B.
Assessments of the impact of aircraft engine exhausts on stratospheric ozone levels are currently limited to 2D zonally-averaged models which, while completely representing chemistry, involve high parameterization of transport processes. Prospective 3D models under development by NASA-Goddard will use winds from a data-assimilation procedure; the upper troposphere/lower stratosphere behavior of one such model has been verified by direct comparison of model simulations with satellite, balloon, and sonde measurements. Attention is presently given to the stratosphere/troposphere exchange and nonzonal distribution of aircraft engine exhaust.
Ortiz Llorente, Maria Begoña
The in-flight entertainment system "Immfly" is a gate-to-gate entertainment system that provides flights passengers a new way of entertainment during their flight until they arrive to their destination. It is a solution that generates a wi-fi network inside the aircraft to which the users can connec
Hennessy, Michael J.
NASA is investigating advanced turboelectric aircraft propulsion systems that use superconducting motors to drive multiple distributed turbofans. Conventional electric motors are too large and heavy to be practical for this application; therefore, superconducting motors are required. In order to improve aircraft maneuverability, variable-speed power converters are required to throttle power to the turbofans. The low operating temperature and the need for lightweight components that place a minimum of additional heat load on the refrigeration system open the possibility of incorporating extremely efficient cryogenic power conversion technology. This Phase II project is developing critical components required to meet these goals.
The notification is defined under the provisions of the regulations for execution of the aviation law. Terms of exclusive loading and container are explained. Transportable radioactive materials hereunder exclude naturally igniting fluid materials, substances necessary to be contained in vessels which filtrate interior gas with filters or refrigerate contents with cooling devices, etc., or BM loads necessary to be continuously ventilated. Radioactive materials to be conveyed as radioactive loads and L loads are prescribed with tables attached. Technical standards for radioactive loads are stipulated for L, A, BM and BU loads respectively. Confirmation of safety of radioactive loads may be made by examiniation of documents prepared by persons acknowledged proper by the Minister of Transportation. Radioactive materials are uranium 233 and 235, plutonium 238, 239 and 241, their compounds and those materials which include one or more than two of such substances. Materials whose quantities or quantities of components are less than 15 grams and natural or depleted uranium are excluded. The maximum doses of containers with radioactive loads shall not exceed for an hour 200 mili-rem on the surface and 10 mili-rem at a distance of 1 meter from the surface. Confirmation of safety of transport, method of loading, prevention of criticality, restriction of mixed shipment, transport index, signals and others are provided for in detail. (Okada, K.)
Straeter, T. A.; Williams, J. R.
The paper describes techniques for testing and validating software for the TCV (Terminal Configured Vehicle) program which is intended to solve problems associated with operating a commercial transport aircraft in the terminal area. The TCV research test bed is a Boeing 737 specially configured with digital computer systems to carry out automatic navigation, guidance, flight controls, and electronic displays research. The techniques developed for time and cost reduction include automatic documentation aids, an automatic software configuration, and an all software generation and validation system.
Estkowski, Regina I. (Inventor)
An unmanned vehicle management system includes an unmanned aircraft system (UAS) control station controlling one or more unmanned vehicles (UV), a collaborative routing system, and a communication network connecting the UAS and the collaborative routing system. The collaborative routing system being configured to receive flight parameters from an operator of the UAS control station and, based on the received flight parameters, automatically present the UAS control station with flight plan options to enable the operator to operate the UV in a defined airspace.
Arcara, P. C., Jr.; Bartlett, D. W.; Mccullers, L. A.
The FLOPS aircraft conceptual design/analysis code has been used to evaluate the effects of incorporating hybrid laminar flow control (HLFC) in a 300-passenger, 6500 n. mi. range, twin-engine subsonic transport aircraft. The baseline configuration was sized to account for 50 percent chord laminar flow on the wing upper surface as well as both surfaces of the empennage airfoils. Attention is given to the additional benefits of achieving various degrees of laminar flow on the engine nacelles, and the horsepower extraction and initial weight and cost increments entailed by the HLFC system. The sensitivity of the results obtained to fuel-price and off-design range are also noted.
... Aeronautics and Space Administration announces a meeting of the Unmanned Aircraft Systems (UAS) Subcommittee... SPACE ADMINISTRATION NASA Advisory Council; Aeronautics Committee; Unmanned Aircraft Systems... of NASA UAS Integration into the National Airspace System (NAS) Phase 2 Activity Selection...
Ardema, M. D.
Sensitivity data for advanced technology transports has been systematically collected. This data has been generated in two separate studies. In the first of these, three nominal, or base point, vehicles designed to cruise at Mach numbers .85, .93, and .98, respectively, were defined. The effects on performance and economics of perturbations to basic parameters in the areas of structures, aerodynamics, and propulsion were then determined. In all cases, aircraft were sized to meet the same payload and range as the nominals. This sensitivity data may be used to assess the relative effects of technology changes. The second study was an assessment of the effect of cruise Mach number. Three families of aircraft were investigated in the Mach number range 0.70 to 0.98: straight wing aircraft from 0.70 to 0.80; sweptwing, non-area ruled aircraft from 0.80 to 0.95; and area ruled aircraft from 0.90 to 0.98. At each Mach number, the values of wing loading, aspect ratio, and bypass ratio which resulted in minimum gross takeoff weight were used. As part of the Mach number study, an assessment of the effect of increased fuel costs was made.
We develop a theory of transport in Hamiltonian systems in the context of iteration of area-preserving maps. Invariant closed curves present complete barriers to transport, but in regions without such curves there are still invariant Cantor sets named cantori, which appear to form major obstacles. The flux through the gaps of the cantori is given by Mather's differences in action. This gives useful bounds on transport between regions, and a universal scaling law for one-parameter families when a curve has just broken, which agree well with numerical experiments of Chirikov and explain an apparent disagreement with results of Greene. By dividing the phase space into regions separated by the strongest barriers, and assuming the motion is mixing within them, we derive a global picture of transport, which can be used, for example, to predict confinement times and to explain longtime tails in the decay of correlations
G. J. M. Velders
Full Text Available A three-dimensional off-line tracer transport model coupled to the ECMWF analyses has been used to study the transport of trace gases in the atmosphere. The model gives a reasonable description of their general transport in the atmosphere. The simulation of the transport of aircraft emissions (as NOx has been studied as well as the transport of passive tracers injected at different altitudes in the North Atlantic flight corridor. A large zonal variation in the NOx concentrations as well as large seasonal and yearly variations was found. The altitude of the flight corridor influences the amount of tracers transported into the troposphere and stratosphere to a great extent.
Wingrove, Earl R., III; Hees, Jing; Villani, James A.; Yackovetsky, Robert E. (Technical Monitor)
Throughout U.S. history, our nation has generally enjoyed exceptional economic growth, driven in part by transportation advancements. Looking forward 25 years, when the national highway and skyway systems are saturated, the nation faces new challenges in creating transportation-driven economic growth and wealth. To meet the national requirement for an improved air traffic management system, NASA developed the goal of tripling throughput over the next 20 years, in all weather conditions while maintaining safety. Analysis of the throughput goal has primarily focused on major airline operations, primarily through the hub and spoke system.However, many suggested concepts to increase throughput may operate outside the hub and spoke system. Examples of such concepts include the Small Aircraft Transportation System, civil tiltrotor, and improved rotorcraft. Proper assessment of the potential contribution of these technologies to the domestic air transportation system requires a modeling capability that includes the country's numerous smaller airports, acting as a fundamental component of the National Air space System, and the demand for such concepts and technologies. Under this task for NASA, the Logistics Management Institute developed higher fidelity demand models that capture the interdependence of short-haul air travel with other transportation modes and explicitly consider the costs of commercial air and other transport modes. To accomplish this work, we generated forecasts of the distribution of general aviation based aircraft and GA itinerant operations at each of nearly 3.000 airport based on changes in economic conditions and demographic trends. We also built modules that estimate the demand for travel by different modes, particularly auto, commercial air, and GA. We examined GA demand from two perspectives: top-down and bottom-up, described in detail.
National Aeronautics and Space Administration — Unmanned aircraft systems (UAS) can be used for scientific, emergency management, and defense missions, among others. The existing federal air regulations,...
Culick, Fred E. C.; Jahnke, Craig C.
Dynamical systems theory has been used to study nonlinear aircraft dynamics. A six degree of freedom model that neglects gravity has been analyzed. The aerodynamic model, supplied by NASA, is for a generic swept wing fighter and includes nonlinearities as functions of the angle of attack. A continuation method was used to calculate the steady states of the aircraft, and bifurcations of these steady states, as functions of the control deflections. Bifurcations were used to predict jump phenomena and the onset of periodic motion for roll coupling instabilities and high angle of attack maneuvers. The predictions were verified with numerical simulations.
Petley, Dennis H.; Jones, Stuart C.; Dziedzic, William M.
Numerical methods have been developed for the analysis of hypersonic aircraft cooling systems. A general purpose finite difference thermal analysis code is used to determine areas which must be cooled. Complex cooling networks of series and parallel flow can be analyzed using a finite difference computer program. Both internal fluid flow and heat transfer are analyzed, because increased heat flow causes a decrease in the flow of the coolant. The steady state solution is a successive point iterative method. The transient analysis uses implicit forward-backward differencing. Several examples of the use of the program in studies of hypersonic aircraft and rockets are provided.
Burke, David A.
One of the pillars of aviation safety is assuring sound engineering practices through airworthiness certification. As Unmanned Aircraft Systems (UAS) grow in popularity, the need for airworthiness standards and verification methods tailored for UAS becomes critical. While airworthiness practices for large UAS may be similar to manned aircraft, it is clear that small UAS require a paradigm shift from the airworthiness practices of manned aircraft. Although small in comparison to manned aircraft these aircraft are not merely remote controlled toys. Small UAS may be complex aircraft flying in the National Airspace System (NAS) over populated areas for extended durations and beyond line of sight of the operators. A comprehensive systems engineering framework for certifying small UAS at the system level is needed. This work presents a point based tool that evaluates small UAS by rewarding good engineering practices in design, analysis, and testing. The airworthiness requirements scale with vehicle size and operational area, while allowing flexibility for new technologies and unique configurations.
Elmer, James D.
This curriculum guide accompanies another publication in the Aerospace Education II series entitled "Propulsion Systems for Aircraft." The guide includes specific guidelines for teachers on each chapter in the textbook. Suggestions are included for objectives (traditional and behavioral), suggested outline, orientation, suggested key points,…
This paper speaks about work conducted in 1998 and 1999 by AEROSPATIALE MATRA in development of an obstacle detection system, which has been tested on a demonstrator aircraft in Toulouse. The purpose of this mock- up was to verify the feasibility of a passive technology, and to consider the limits of its use.
Athans, M.; Willner, D.
A flight control system design is presented, that can be implemented by analog hardware, to be used to control an aircraft with uncertain parameters. The design is based upon the use of modern control theory. The ideas are illustrated by considering control of STOL longitudinal dynamics.
Berg, F. van den; Eisses, A.R.; Beek, P.J.G. van
A new approach for an airport noise monitoring system is presented that comprises not only a number of measuring stations, but also a dedicated sound propagation model and an aircraft noise emission model. This approach enables estimation of noise levels in the whole area around the airport and not
Full Text Available Contemporary transport aircraft information-communication system is extremely sophisticated. The aim of the current study is to give contribution to the current knowledge of information entropy, and to show how its alteration could indicate possible errors, which may lead to preventing future aircraft calamities. In this study a principle model of such system is described, consisting of two peripheral, sensory units and their central, processing units, upon which a numerical simulation is carried out. Two states of the system are defined – states of regular and irregular dynamics. Data transfer between system elements is defined through information entropy, whose average change and accompanying standard deviation shows the difference between the regular and non-regular state. When introducing an error of the same kind upon each of the sensors, the type of results corresponds to a sufficiently intensive deviation, which may make error detection by information entropy analysis possible.
Banerjee, J. R.
The purpose of this paper is to provide theory, results, discussion and conclusions arising from an in-depth investigation on the modal behaviour of high aspect ratio aircraft wings. The illustrative examples chosen are representative of sailplane and transport airliner wings. To achieve this objective, the dynamic stiffness method of modal analysis is used. The wing is represented by a series of dynamic stiffness elements of bending-torsion coupled beams which are assembled to form the overall dynamic stiffness matrix of the complete wing. With cantilever boundary condition applied at the root, the eigenvalue problem is formulated and finally solved with the help of the Wittrick-Williams algorithm to yield the eigenvalues and eigenmodes which are essentially the natural frequencies and mode shapes of the wing. Results for wings of two sailplanes and four transport aircraft are discussed and finally some conclusions are drawn
Pirrello, C. J.; Baker, A. H.; Stone, J. E.
A detailed analytical study was made to investigate the effects of fuselage cross section (circular and elliptical) and the structural arrangement (integral and nonintegral tanks) on aircraft performance. The vehicle was a 200 passenger, liquid hydrogen fueled Mach 6 transport designed to meet a range goal of 9.26 Mn (5000 NM). A variety of trade studies were conducted in the area of configuration arrangement, structural design, and active cooling design in order to maximize the performance of each of three point design aircraft: (1) circular wing-body with nonintegral tanks, (2) circular wing-body with integral tanks and (3) elliptical blended wing-body with integral tanks. Aircraft range and weight were used as the basis for comparison. The resulting design and performance characteristics show that the blended body integral tank aircraft weights the least and has the greatest range capability, however, producibility and maintainability factors favor nonintegral tank concepts.
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 ...
National Aeronautics and Space Administration — It is proposed to develop an accurate in-service aircraft engine life monitor system for the prediction of remaining component and system life for aircraft engines....
...: Meeting Notice of RTCA Special Committee 203, Unmanned Aircraft Systems. SUMMARY: The FAA is issuing this... Document--Operational Functional Requirements and Safety Objectives for Unmanned Aircraft Systems and... Federal Aviation Administration Twenty Fourth Meeting: RTCA Special Committee 203, Unmanned...
Full Text Available At large international airports, aircraft can be refuelled either by fuel trucks or using dedicated underground pipeline systems. The latter, hydrant refuelling, is considered to be an optimal fuelling method as it increases safety, shortens the aircraft turnaround time and cuts the overall costs. However, at smaller airports, implementation of this system can lead to high investment costs. Thus, the paper discusses the airport size from which this system may be efficient to implement. Various definitions of term “airport size” are assessed. Based on data collection, the hydrant system model is created within the paper. As a result, methodology for assessing the suitability of hydrant system implementation is set. This methodology can be used at every airport using three simple inputs.
Bond, E. Q.; Carroll, E. A.; Flume, R. A.
A comparison is made between airplane productivity and utilization levels derived from commercial airline type schedules which were developed for two subsonic and four supersonic cruise speed aircraft. The cruise speed component is the only difference between the schedules which are based on 1995 passenger demand forecasts. Productivity-to-speed relationships were determined for the three discrete route systems: North Atlantic, Trans-Pacific, and North-South America. Selected combinations of these route systems were also studied. Other areas affecting the productivity-to-speed relationship such as aircraft design range and scheduled turn time were examined.
The safety of spent fuel transport casks in severe accident conditions is always a matter of concern. This paper surveys German missile impact tests that have been carried out in the past to demonstrate that German cask designs for transport and interim storage are safe even under conditions of an aircraft crash impact. A fire test with a cask beside an exploding propane vessel and temperature calculations concerning prolonged fires also show that the casks have reasonably good safety margins in thermal accidents beyond regulatory fire test conditions. (author)
Smith, Jeremy C.; Viken, Jeffrey K.; Guerreiro, Nelson M.; Dollyhigh, Samuel M.; Fenbert, James W.; Hartman, Christopher L.; Kwa, Teck-Seng; Moore, Mark D.
Electric propulsion and autonomy are technology frontiers that offer tremendous potential to achieve low operating costs for small-aircraft. Such technologies enable simple and safe to operate vehicles that could dramatically improve regional transportation accessibility and speed through point-to-point operations. This analysis develops an understanding of the potential traffic volume and National Airspace System (NAS) capacity for small on-demand aircraft operations. Future demand projections use the Transportation Systems Analysis Model (TSAM), a tool suite developed by NASA and the Transportation Laboratory of Virginia Polytechnic Institute. Demand projections from TSAM contain the mode of travel, number of trips and geographic distribution of trips. For this study, the mode of travel can be commercial aircraft, automobile and on-demand aircraft. NASA's Airspace Concept Evaluation System (ACES) is used to assess NAS impact. This simulation takes a schedule that includes all flights: commercial passenger and cargo; conventional General Aviation and on-demand small aircraft, and operates them in the simulated NAS. The results of this analysis projects very large trip numbers for an on-demand air transportation system competitive with automobiles in cost per passenger mile. The significance is this type of air transportation can enhance mobility for communities that currently lack access to commercial air transportation. Another significant finding is that the large numbers of operations can have an impact on the current NAS infrastructure used by commercial airlines and cargo operators, even if on-demand traffic does not use the 28 airports in the Continental U.S. designated as large hubs by the FAA. Some smaller airports will experience greater demand than their current capacity allows and will require upgrading. In addition, in future years as demand grows and vehicle performance improves other non-conventional facilities such as short runways incorporated into
...: Unmanned Aircraft Systems. SUMMARY: The FAA is issuing this notice to advise the public of a meeting of RTCA Special Committee 203: Unmanned Aircraft Systems. DATES: The meeting will be held October 19-21... Special Committee 203: Unmanned Aircraft Systems meeting. The agenda will include: Tuesday, October 19 9...
... Federal Aviation Administration Nineteenth Meeting: RTCA Special Committee 203: Unmanned Aircraft Systems...: Unmanned Aircraft Systems. SUMMARY: The FAA is issuing this notice to advise the public of a meeting of RTCA Special Committee 203: Unmanned Aircraft Systems. DATES: The meeting will be held May 17-19,...
...: Unmanned Aircraft Systems. SUMMARY: The FAA is issuing this notice to advise the public of a meeting of RTCA Special Committee 203: Unmanned Aircraft Systems. DATES: The meeting will be held June 8-10, 2010... given for a Special Committee 203: Unmanned Aircraft Systems meeting. The agenda will include:...
...: Unmanned Aircraft Systems. SUMMARY: The FAA is issuing this notice to advise the public of a meeting of RTCA Special Committee 203: Unmanned Aircraft Systems. DATES: The meeting will be held February 16-18...: Unmanned Aircraft Systems meeting. The agenda will include: February 16, 2010 Opening Plenary...
... carrier operations and maintenance program (14 CFR part 43, 14 CFR part 91, 14 CFR part 121). (b) Each... § 141.804 Aircraft water system operations and maintenance plan. (a) Each air carrier must develop and implement an aircraft water system operations and maintenance plan for each aircraft water system that...
This Individual Research Project (IRP) is the extension research to the group design project (GDP) work which the author has participated in his Msc programme. The GDP objective is to complete the conceptual design of a 200-seat, flying wing civil airliner—FW-11. The next generation aircraft design demands higher reliability, safety and maintainability. With the development of the vehicle hydraulic system technology, the equipment and systems become more and more complex, their reliability...
In passing the Nuclear Waste Policy Act of 1982 (NWPA), the United States Congress initiated a systematic process for addressing the national problem of what to do with the growing inventory of high-level nuclear waste and spent fuel. In addition to requiring development of geologic repositories, the NWPA directed the Secretary of Energy to perform a detailed study of the need for, and the feasibility of, monitored retrievable storage (MRS) and to submit to Congress a proposal for construction of one or more MRS facilities. As a third element of the disposal system, the NWPA also directed the development of the transportation capability to ship the nuclear wastes from the points of origin (chiefly reactors at commercial power plants) to the facilities developed under the NWPA. The Office of Civilian Radioactive Waste Management (OCRWM) of the Department of Energy (DOE) was created to manage the overall disposal program. Within OCRWM, the Office of Storage and Transportation Systems (OSTS) is responsible for developing the mandated proposal for an MRS facility, establishing the transportation capability to support the disposal operation, and directing the integrated development of system components so that the entire waste system functions in an optimized way. This paper deals only peripherally with the DOE proposal for an MRS facility since an in-depth paper on that program will be delivered at a later session of this meeting. The primary focus of this discussion is the program that OCRWM is developing to ensure the availability of a safe, efficient transportation system for shipping under provisions of the NWPA
... an Airline Transport Pilot Certificate J Appendix J to Part 141 Aeronautics and Space FEDERAL... Airline Transport Pilot Certificate 1. Applicability. This appendix prescribes the minimum curriculum for an aircraft type rating course other than an airline transport pilot certificate, for: (a) A...
Bin ZHANG; Bao-guo YAO; Ying-lin KE
A novel 6-degree of freedom (DOF) posture alignment system, based on 3-DOF positioners, is presented for the assembly of aircraft wings. Each positioner is connected with the wing through a rotational and adsorptive half-ball shaped end-effector, and the positioners together with the wing are considered as a 3-PPPS (P denotes a prismatic joint and S denotes a spherical joint) redundantly actuated parallel mechanism. The kinematic model of this system is established and a trajectory planning method is introduced. A complete analysis of inverse dynamics is carried out with the Newton-Euler algorithm, which is used to find the desired actuating torque in the design and path planning phase. Simulation analysis of the displacement and actuating torque of each joint of the positioners based on inverse kinematics and dynamics is conducted, and the results show that the system is feasible for the posture alignment of aircraft wings.
This book provides a systematic analysis, modeling and evaluation of the performance of advanced transport systems. It offers an innovative approach by presenting a multidimensional examination of the performance of advanced transport systems and transport modes, useful for both theoretical and practical purposes. Advanced transport systems for the twenty-first century are characterized by the superiority of one or several of their infrastructural, technical/technological, operational, economic, environmental, social, and policy performances as compared to their conventional counterparts. The advanced transport systems considered include: Bus Rapid Transit (BRT) and Personal Rapid Transit (PRT) systems in urban area(s), electric and fuel cell passenger cars, high speed tilting trains, High Speed Rail (HSR), Trans Rapid Maglev (TRM), Evacuated Tube Transport system (ETT), advanced commercial subsonic and Supersonic Transport Aircraft (STA), conventionally- and Liquid Hydrogen (LH2)-fuelled commercial air trans...
Cherry, G. W.
Consideration of the problems facing air transport at present, and to be expected in the future. In the Northeast Corridor these problems involve community acceptance, airway and airport congestion and delays, passenger acceptance, noise reduction, and improvements in low-density short-haul economics. In the development of a superior short-haul operating system, terminal-configured vs cruise-configured vehicles are evaluated. CTOL, STOL, and VTOL aircraft of various types are discussed. In the field of noise abatement, it is shown that flight procedural techniques are capable of supplementing ?quiet engine' technology.
National Aeronautics and Space Administration — Hybrid turboelectric aircraft with gas turbines driving electric generators connected to electric propulsion motors have the potential to transform the aircraft...
Laue, Jay H.
This document is the final report by the Science Applications International Corporation (SAIC) on contracted support provided to the National Aeronautics and Space Administration (NASA) under Contract NAS8-99060, 'Space Transportation Systems Technologies'. This contract, initiated by NASA's Marshall Space Flight Center (MSFC) on February 8, 1999, was focused on space systems technologies that directly support NASA's space flight goals. It was awarded as a Cost-Plus-Incentive-Fee (CPIF) contract to SAIC, following a competitive procurement via NASA Research Announcement, NRA 8-21. This NRA was specifically focused on tasks related to Reusable Launch Vehicles (RLVs). Through Task Area 3 (TA-3), "Other Related Technology" of this NRA contract, SAIC extensively supported the Space Transportation Directorate of MSFC in effectively directing, integrating, and setting its mission, operations, and safety priorities for future RLV-focused space flight. Following an initially contracted Base Year (February 8, 1999 through September 30, 1999), two option years were added to the contract. These were Option Year 1 (October 1, 1999 through September 30, 2000) and Option Year 2 (October 1, 2000 through September 30, 2001). This report overviews SAIC's accomplishments for the Base Year, Option Year 1, and Option Year 2, and summarizes the support provided by SAIC to the Space Transportation Directorate, NASA/MSFC.
... Federal Aviation Administration Twentieth Meeting: RTCA Special Committee 203, Unmanned Aircraft Systems... RTCA Special Committee 203, Unmanned Aircraft Systems. SUMMARY: The FAA is issuing this notice to advise the public of the twentieth meeting of RTCA Special Committee 203, Unmanned Aircraft...
A software house Oy Fision Ltd decided to develop a custom information system to help in continuing airworthiness management of general aviation aircraft. The project was put in motion as a master’s thesis project by the author. Helicopter continuing airworthiness management and maintenance company Helitech Oy became a partner in the project. The paper starts by introducing regulations for continuing airworthiness management and requirements due to the regulations in daily work of a conti...
Darnell, Bart W.
Unmanned aircraft systems (UAS) have been part of aviation from the beginnings of manned aviation and have become a vital tool of our overseas military and national security operations. Public and private sector interest continues to grow for UAS to be used in a variety of domestic missions, such as border patrol, law enforcement, and search and rescue. With growing concerns over issues, such as border security and critical infrastructure protection, it would seem that UAS would be a logical ...
Full text: Aircraft fighter pilots may experience risks other than the cosmic radiation exposure due to the characteristics of a typical fighter flight. The combined risks for fighter pilots due to the G-forces, hypobaric hypoxia, cosmic radiation exposure, etc. have determined that pregnant female pilots should remain on ground. However, several military transport missions can be considered an ordinary civil aircraft flight and the question arises whether the pregnant female pilot could be part of the aircrew. In this work the cosmic radiation dose received in several transport missions was estimated. Typical transport missions carried out in one month by a single air squad were considered. The flights departured from Lisbon to areas such as the Azores, to several countries in central and southern Africa, to the western coast of the USA and to the Balkans and an estimate of the cosmic radiation dose received on each flight was carried out. A monthly average cosmic radiation dose to the aircrew was determined and the dose values obtained were discussed in relation to the limits established by the European Union Council Directive 96/29/Euratom. The cosmic ray dose estimates were performed using the EPCARD v3.2 and the CARI-6 computing codes. EPCARD v3.2 was kindly made available by GSF-National Research Centre for Environment and Health, Institute of Radiation Protection (Neuherberg, Germany). CARI-6 (version July 7th, 2004) was downloaded from the web site of the Civil Aerospace Medical Institute, Federal Aviation Administration (USA). In this work an estimate of the cosmic radiation dose received by military aircraft crew on realistic typical transport missions is made. (author)
Gratton, GB; Porteous, TC
The UK microlight aircraft community, under the guidance of the British Microlight Aircraft Association (BMAA), has developed a formalised system for the training and qualification of civil test pilots on this class of aircraft. This system is unique in Britain where most of the rest of the industry relies upon a pool of military-trained test aircrew, most of whom have no experience of microlight aircraft. This paper describes the system operated by the BMAA for the training and qualifica...
Żurek Józef; Grzesik Norbert; Kurpas Jakub
The paper describes Zlin 143Lsi aircraft engine work parameters control support method – hourly fuel flow as a main factor under consideration. The method concerns project of aircraft throttle control support system with use of fuzzy logic (fuzzy inference). The primary purpose of the system is aircraft performance optimization, reducing flight cost at the same time and support proper aircraft engine maintenance. Matlab Software and Fuzzy Logic Toolbox were used in the project. Work of the sy...
Cestino, Enrico; Borello, Fabio; Romeo, Giulio
Fuel cells could become the main power source for small general aviation aircraft or could replace APU and internal sub-systems on larger aircraft, to obtain all-electric or more-electric air vehicles. There are several potential advantages of using such a power source, that range from environmental and economic issues to performance and operability aspects. A preliminary design is reported. Also, the paper contains a description of testing activities related to experimental flights of an all...
Ryder, Claire; Highwood, Ellie; Rosenberg, Phil; Trembath, Jamie; Brooke, Jennifer; Bart, Mark; Dean, Angela; Dorsey, James; Crosier, Jonny; McQuaid, Jim; Brindley, Helen; Banks, James; Marsham, John; Sodemann, Harald; Washington, Richard
Measurements of Saharan dust from recent airborne campaigns have found variations in size distributions and optical properties across Saharan and sub-Saharan Africa. These variations have an impact on radiation and thus weather and climate, and are important to characterise and understand, in particular, to understand how they vary with time after dust uplift, transport, and height in the atmosphere. New in-situ aircraft measurements from the Fennec 2011 aircraft campaign over a remote part of the Sahara Desert and the Atlantic Ocean will be presented and compared to previous airborne measurements. Size distributions extending to 300 μm will be shown, representing measurements extending further into the coarse mode than previously published for Saharan dust. The dust sampled by the aircraft covered a wide variety of loadings, dust source regions (Mali, Mauritania and Algeria) and dust ages (from fresh uplift to several days old). A significant coarse mode was present in the size distribution measurements with effective diameter up to 23 μm, and the mean size distribution showed greater concentrations of coarse mode than previous aircraft measurements. Single scattering albedo (SSA) values at 550nm calculated from these size distributions revealed high absorption from 0.77 to 0.95, with a mean of 0.85. Directly measured SSA values were higher (0.91 to 0.99) but new instrumentation revealed that these direct measurements, behind Rosemount inlets, overestimate the SSA by 0.02 to 0.20 depending on the concentration of coarse particles present. This is caused by inlet inefficiencies and pipe losses. Previous measurements of SSA from aircraft measurements may also have been overestimates for this reason. This has a significant impact on atmospheric heating rates. The largest dust particles were encountered closest to the ground, and were most abundant in cases where dust was freshly uplifted. Number concentration, mass loading and extinction coefficient showed inverse
John P.T. Mo
Full Text Available The Australian Defence Force and industry are undergoing significant changes in the way they work together in capability enhancement programs. There are capability gaps in maintaining and supporting current obligations during major asset acquisition, which has migrated into the front line of Royal Air Force Fighter Groups as a new capability. This paper examines a steady state support solution and argues that in order to interchange from one support solution to a new architecture there must be a period for transition, which may need its own interim business model and operational service. A preliminary study of several existing support solutions reveals the generic elements that need to be parameterized and traced through the support system architecture trajectory.
Zertuche, Tony; Mckinnie, James
Three missions have been identified by NASA for a Space Shuttle-supplementing Alternate Transportation System (ATS) encompassing combinations of booster vehicles, crew modules, and service modules: (1) to achieve manned access to orbit for Space Station crew rotation every 90 days, (2) the lofting of a logistics module resupplying the Space Station every 180 days, and (3) the simultaneous launch of both crews and logistics to the Space Station. A reentry glider is considered, in conjunction with the Space Shuttle's unmanned cargo version and the Apollo manned capsule, as an important ATS element. The Titan IV/NUS is used as a booster.
Mukhopadhyay, Vivek; Welstead, Jason R.; Quinlan, Jesse R.; Guynn, Mark D.
Structural configuration analysis of an advanced aircraft fuselage concept is investigated. This concept is characterized by a double-bubble section fuselage with rear mounted engines. Based on lessons learned from structural systems analysis of unconventional aircraft, high-fidelity finite-element models (FEM) are developed for evaluating structural performance of three double-bubble section configurations. Structural sizing and stress analysis are applied for design improvement and weight reduction. Among the three double-bubble configurations, the double-D cross-section fuselage design was found to have a relatively lower structural weight. The structural FEM weights of these three double-bubble fuselage section concepts are also compared with several cylindrical fuselage models. Since these fuselage concepts are different in size, shape and material, the fuselage structural FEM weights are normalized by the corresponding passenger floor area for a relative comparison. This structural systems analysis indicates that an advanced composite double-D section fuselage may have a relative structural weight ratio advantage over a conventional aluminum fuselage. Ten commercial and conceptual aircraft fuselage structural weight estimates, which are empirically derived from the corresponding maximum takeoff gross weight, are also presented and compared with the FEM- based estimates for possible correlation. A conceptual full vehicle FEM model with a double-D fuselage is also developed for preliminary structural analysis and weight estimation.
Full Text Available Objectives: For the purpose of flight safety military aircrew must be healthy. P-wave dispersion (PWD is the p-wave length difference in an electrocardiographic (ECG examination and represents the risk of developing atrial fibrillation. In the study we aimed at investigating PWD in healthy military aircrew who reported for periodical examinations. Material and Methods: Seventy-five asymptomatic military aircrew were enrolled in the study. All the subjects underwent physical, radiologic and biochemical examinations, and a 12-lead electrocardiography. P-wave dispersions were calculated. Results: The mean age of the study participants was 36.15±8.97 years and the mean p-wave duration was 100.8±12 ms in the whole group. Forty-seven subjects were non-pilot aircrew, and 28 were pilots. Thirteen study subjects were serving in jets, 49 in helicopters, and 13 were transport aircraft pilots. Thirty-six of the helicopter and 11 of the transport aircraft aircrew were non-pilot aircrew. P-wave dispersion was the lowest in the transport aircraft aircrew, and the highest in jet pilots. P-wave dispersions were similar in the pilots and non-pilot aircrew. Twenty-three study subjects were overweight, 19 had thyroiditis, 26 had hepatosteatosis, 4 had hyperbilirubinemia, 2 had hypertension, and 5 had hyperlipidemia. The PWD was significantly associated with thyroid-stimulating hormone (TSH levels. Serum uric acid levels were associated with p-wave durations. Serum TSH levels were the most important predictor of PWD. Conclusions: When TSH levels were associated with PWD, uric acid levels were associated with p-wave duration in the military aircrew. The jet pilots had higher PWDs. These findings reveal that military jet pilots may have a higher risk of developing atrial fibrillation, and PWD should be recorded during periodical examinations.
This book gives as systematic application of the methods of physical kinetics to phonon systems. The results presented are of direct relevance to materials whose transport and other properties are dominated by phonons. This class of materials includes most common dielectrics as well as such unusual substances as He-II, glasses and some semiconductors. The theory is presented in its rigorous mathematical formulation, and qualitative physical reasoning is given only to elucidate some of the results thus obtained. An introductory chapter, containing the derivation of phonon spectra in the harmonic approximation and the perturbative treatment of anharmonicity as well as the fundamentals of physical kinetics, makes the text accessible for those who enter this field as beginners. Subsequent chapters deal with heat transport, second sound, dielectric losses, sound attenuation, etc. The basic equations of phonon hydrodynamics and the superdiffusion equation are derived and solved for specific cases. The application of sophisticated field-theoretical methods (Kubo formula, Feynman diagrams) is limited and delegated to an appendix, because they only exceptionally go beyond what ordinary quantum-mechanical perturbation theory or the Boltzmann equation provide for the systems under consideration. Th0191thor's preference for the less formal approach gives the reader a grip of the physical significance of the assumptions involved and thus of the limits of validity of the theory. (Auth.)
Unscheduled aircraft maintenance causes a lot problems and costs for aircraft operators. This is due to the fact that aircraft cause significant costs if flights have to be delayed or canceled and because spares are not always available at any place and sometimes have to be shipped across the world. Reducing the number of unscheduled maintenance is thus a great costs factor for aircraft operators. This thesis describes three methods for aircraft health monitoring and prediction; one method fo...
Leavitt, L. D.; Washburn, A. E.; Wahls, R. A.
NASA has had a long history in fundamental and applied high lift research. Current programs provide a focus on the validation of technologies and tools that will enable extremely short take off and landing coupled with efficient cruise performance, simple flaps with flow control for improved effectiveness, circulation control wing concepts, some exploration into new aircraft concepts, and partnership with Air Force Research Lab in mobility. Transport high-lift development testing will shift more toward mid and high Rn facilities at least until the question: "How much Rn is required" is answered. This viewgraph presentation provides an overview of High-Lift research at NASA.
Purpose: To enable automatic transportation of nuclear substances with optional setting for the transportation distance, even for a long distance, facilitating the automation of the transportation and decreasing the space for the installation of a direction converging section of the transporting path. Constitution: A transporting vehicle having a pair of permanent magnets or ferromagnetic bodies mounted with a predetermined gap to each other along the transporting direction is provided in the transporting path including a bent direction change section for transporting specimens such as nuclear materials, and a plurality of driving vehicles having permanent magnets or ferromagnetic bodies for magnetically attracting the transporting vehicle from outside of the transporting path are arranged to the outside of the transporting path. At least one of the driving vehicles is made to run along the transporting direction of the transporting path by a driving mechanism incorporating running section such as an endless chain to drive the transportation vehicle, and the transporting vehicle is successively driven by each of the driving mechanisms. (Kawakami, Y.)
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 ...
Kavehrad, Mohsen; Fadlullah, Jarir
This paper focuses on leveraging the progress in semiconductor technologies to facilitate production of efficient light-based in-flight entertainment (IFE), distributed sensing, navigation and control systems. We demonstrate the ease of configuring "engineered pipes" using cheap lenses, etc. to achieve simple linear transmission capacity growth. Investigation of energy-efficient, miniaturized transceivers will create a wireless medium, for both inter and intra aircrafts, providing enhanced security, and improved quality-of-service for communications links in greater harmony with onboard systems. The applications will seamlessly inter-connect multiple intelligent devices in a network that is deployable for aircrafts navigation systems, onboard sensors and entertainment data delivery systems, and high-definition audio-visual broadcasting systems. Recent experimental results on a high-capacity infrared (808 nm) system are presented. The light source can be applied in a hybrid package along with a visible lighting LED for both lighting and communications. Also, we present a pragmatic combination of light communications through "Spotlighting" and existing onboard power-lines. It is demonstrated in details that a high-capacity IFE visible light system communicating over existing power-lines (VLC/PLC) may lead to savings in many areas through reduction of size, weight and energy consumption. This paper addresses the challenges of integrating optimized optical devices in the variety of environments described above, and presents mitigation and tailoring approaches for a multi-purpose optical network.
Inteligentni transportni sistemi pri načrtovanju in usklajevanju gibanja in parkiranja letal na ploščadi letališča: Intelligent transportation systems in the planning and coordination of aircraft traffic at the airport apron:
Pavlin, Stanislav; Roguljić, Slavko
Airport aprons are areas for aircraft handling, parking and maintenance. According to international rules the number of positions at the apron has to be at least equal to the number of aircraft staying at any one time at the airport. The air traffic at Split Airport increased rapidly in the mid-90s when it became the UN logistics base for Bosnia and Herzegovina. There were nomeans nor free space for further expansion of the apron, so the traffic had to be reorganised and re-coordinated. Alter...
In this publication has been presented selected aspects of the wide spectrum of Unmanned Aircraft Systems (UAS)/UAV adaptation within the military structures. With regard to many years of experience of the author within the national and NATO Integrated Air Defence Command and Control System, the objective paper is also related to the Airspace Management (ASM) in the light of present and future use of UAS in this environment. Wider and wider application of UAS in many areas of human life as w...
Dinallo, Michael Anthony; Lopez, Christopher D.
An aircraft wire systems laboratory has been developed to support technical maturation of diagnostic technologies being used in the aviation community for detection of faulty attributes of wiring systems. The design and development rationale of the laboratory is based in part on documented findings published by the aviation community. The main resource at the laboratory is a test bed enclosure that is populated with aged and newly assembled wire harnesses that have known defects. This report provides the test bed design and harness selection rationale, harness assembly and defect fabrication procedures, and descriptions of the laboratory for usage by the aviation community.
Jacob, Daniel James; Crawford, James; Kleb, Mary; Connors, VIckie; Bendura, Richard; Raper, James; Sachse, Glen; Gille, John; Emmons, Louisa; Heald, Colette
The NASA Transport and Chemical Evolution over the Pacific (TRACE-P) aircraft mission was conducted in February–April 2001 over the NW Pacific (1) to characterize the Asian chemical outflow and relate it quantitatively to its sources and (2) to determine its chemical evolution. It used two aircraft, a DC-8 and a P-3B, operating out of Hong Kong and Yokota Air Force Base (near Tokyo), with secondary sites in Hawaii, Wake Island, Guam, Okinawa, and Midway. The aircraft carried instrumentation f...
de Castro, Helena V.
The blended-wing-body (BWB) configuration appears as a promising contender for the next generation of large transport aircraft. The idea of blending the wing with the fuselage and eliminating the tail is not new, it has long been known that tailless aircraft can suffer from stability and control problems that must be addressed early in the design. This thesis is concerned with identifying and then evaluating the flight dynamics, stability, flight controls and handling qualities of a generic B...
Howell, Charles T., III
Research is needed to determine what procedures, aircraft sensors and other systems will be required to allow Unmanned Aerial Systems (UAS) to safely operate with manned aircraft in the National Airspace System (NAS). This paper explores the use of Unmanned Aerial System (UAS) Surrogate research aircraft to serve as platforms for UAS systems research, development, and flight testing. These aircraft would be manned with safety pilots and researchers that would allow for flight operations almost anywhere in the NAS without the need for a Federal Aviation Administration (FAA) Certificate of Authorization (COA). With pilot override capability, these UAS Surrogate aircraft would be controlled from ground stations like true UAS s. It would be possible to file and fly these UAS Surrogate aircraft in the NAS with normal traffic and they would be better platforms for real world UAS research and development over existing vehicles flying in restricted ranges or other sterilized airspace. These UAS surrogate aircraft could be outfitted with research systems as required such as computers, state sensors, video recording, data acquisition, data link, telemetry, instrumentation, and Automatic Dependent Surveillance-Broadcast (ADS-B). These surrogate aircraft could also be linked to onboard or ground based simulation facilities to further extend UAS research capabilities. Potential areas for UAS Surrogate research include the development, flight test and evaluation of sensors to aide in the process of air traffic "see-and-avoid". These and other sensors could be evaluated in real-time and compared with onboard human evaluation pilots. This paper examines the feasibility of using UAS Surrogate research aircraft as test platforms for a variety of UAS related research.
... (65 FR 19477-78) or you may visit http://DocketsInfo.dot.gov . ] Docket: To read background documents... and Procedures of the Department of Transportation (DOT) (44 FR 1134, February 26, 1979) provide that... Aircraft and Airmen for the Operation of Light-Sport Aircraft'' (Sport Pilot Rule) (69 FR 44772, July...
The Nuclear Waste Policy Act of 1982 (NWPA), as amended, authorized the DOE to develop and manage a Federal system for the disposal of SNF and HLW. OCRWM was created to manage acceptance and disposal of SNF and HLW in a manner that protects public health, safety, and the environment; enhances national and energy security; and merits public confidence. This responsibility includes managing the transportation of SNF and HLW from origin sites to the Repository for disposal. The Transportation System Concept of Operations is the core high-level OCRWM document written to describe the Transportation System integrated design and present the vision, mission, and goals for Transportation System operations. By defining the functions, processes, and critical interfaces of this system early in the system development phase, programmatic risks are minimized, system costs are contained, and system operations are better managed, safer, and more secure. This document also facilitates discussions and understanding among parties responsible for the design, development, and operation of the Transportation System. Such understanding is important for the timely development of system requirements and identification of system interfaces. Information provided in the Transportation System Concept of Operations includes: the functions and key components of the Transportation System; system component interactions; flows of information within the system; the general operating sequences; and the internal and external factors affecting transportation operations. The Transportation System Concept of Operations reflects OCRWM's overall waste management system policies and mission objectives, and as such provides a description of the preferred state of system operation. The description of general Transportation System operating functions in the Transportation System Concept of Operations is the first step in the OCRWM systems engineering process, establishing the starting point for the lower
Subramanian, Shreyas Vathul
This research combines the disciplines of system-of-systems (SoS) modeling, platform-based design, optimization and evolving design spaces to achieve a novel capability for designing solutions to key aeronautical mission challenges. A central innovation in this approach is the confluence of multi-level modeling (from sub-systems to the aircraft system to aeronautical system-of-systems) in a way that coordinates the appropriate problem formulations at each level and enables parametric search in design libraries for solutions that satisfy level-specific objectives. The work here addresses the topic of SoS optimization and discusses problem formulation, solution strategy, the need for new algorithms that address special features of this problem type, and also demonstrates these concepts using two example application problems - a surveillance UAV swarm problem, and the design of noise optimal aircraft and approach procedures. This topic is critical since most new capabilities in aeronautics will be provided not just by a single air vehicle, but by aeronautical Systems of Systems (SoS). At the same time, many new aircraft concepts are pressing the boundaries of cyber-physical complexity through the myriad of dynamic and adaptive sub-systems that are rising up the TRL (Technology Readiness Level) scale. This compositional approach is envisioned to be active at three levels: validated sub-systems are integrated to form conceptual aircraft, which are further connected with others to perform a challenging mission capability at the SoS level. While these multiple levels represent layers of physical abstraction, each discipline is associated with tools of varying fidelity forming strata of 'analysis abstraction'. Further, the design (composition) will be guided by a suitable hierarchical complexity metric formulated for the management of complexity in both the problem (as part of the generative procedure and selection of fidelity level) and the product (i.e., is the mission
Zedek, Sabeha; Zedek, Sabeha Fettouma; Escriba, Christophe; Fourniols, Jean-Yves
Our main subject of interest is the Structural Health Monitoring in aeronautics. Most of our works are dedicated to the detection of delamination disbonds and cracks in heterogeneous (Composite) and homogenous (aluminum 2024) structures of an aircraft structure. To successfully combine detection and alert generation we based our approach on the use of new generation of chip called SoC (System on Chip). We tried to develop an autonomous system able to detect damages on aircraft structure. Acco...
National Aeronautics and Space Administration — Hybrid turbo-electric aircraft with gas turbines driving electric generators connected to electric propulsion motors have the potential to transform the aircraft...
Krause, Hans-Joachim; Hohmann, Rainer; Grueneklee, Michael; Zhang, Yi; Braginski, Alex I.
For the detection of deep-lying flaws in aircraft structures, a mobile eddy-current system is being developed in conjunction with a high-temperature superconductor (Yba_2Cu_3O_7) thin-film HTS SQUID gradiometer. The challenge is to operate the SQUID sensor during movement in strong ambient fields, independent of orientation. A planar rf double hole gradiometer with a gradient sensitivity of 500 fT/(cm √Hz) was designed for that purpose. Two different cooling concepts were successfully implemented: the SQUID operation in the vacuum region of a lightweight nitrogen cryostat, constructed for operation in any orientation, and the use of a commercial Joule-Thomson cryocooler for liquid-nitrogen-free SQUID cooling. With a SQUID integration scheme using a sapphire cold finger, motion-related additional noise is nearly eliminated. Using a system equipped with a differential eddy current excitation, two-dimensional scans were performed to find fatigue cracks and corrosion pits hidden below several layers of aluminum. For demonstration in the Lufthansa maintenance facility at Frankfurt Airport, the system was used to detect flaws in aircraft wheels. Work in progress includes developing longer base gradiometers for detection of deep flaws.
This document provided an assessment of the Canadian hydrocarbon transportation system. In addition to regulating the construction and operation of Canada's 45,000 km of pipeline that cross international and provincial borders, Canada's National Energy Board (NEB) regulates the trade of natural gas, oil and natural gas liquids. The ability of pipelines to delivery this energy is critical to the country's economic prosperity. The pipeline system includes large-diameter, cross-country, high-pressure natural gas pipelines, low-pressure crude oil and oil products pipelines and small-diameter pipelines. In order to assess the hydrocarbon transportation system, staff at the NEB collected data from pipeline companies and a range of publicly available sources. The Board also held discussions with members of the investment community regarding capital markets and emerging issues. The assessment focused largely on evaluating whether Canadians benefit from an efficient energy infrastructure and markets. The safety and environmental integrity of the pipeline system was also evaluated. The current adequacy of pipeline capacity was assessed based on price differentials compared with firm service tolls for major transportation paths; capacity utilization on pipelines; and, the degree of apportionment on major oil pipelines. The NEB concluded that the Canadian hydrocarbon transportation system is working effectively, with an adequate capacity in place on existing natural gas pipelines, but with a tight capacity on oil pipelines. It was noted that shippers continue to indicate that they are reasonably satisfied with the services provided by pipeline companies and that the NEB-regulated pipeline companies are financially stable. 14 refs, 11 tabs., 28 figs., 4 appendices
Chevillot, Fabrice; Sinou, Jean-Jacques; Hardouin, Nicolas
International audience Friction-induced vibration is still a cause for concern in a wide variety of mechanical systems, because it can lead to structural damage if high vibration levels are reached. Another effect is the noise produced that can be very unpleasant for end-users, thereby making it a major problem in the field of terrestrial transport. In this work the case of an aircraft braking system is examined. An analytical model with polynomial nonlinearity in the contact between rotor...
Pace, Scott; Oria, A. J.; Guckian, Paul; Nguyen, Truong X.
This report compiles and analyzes tests that were conducted to measure cell phone spurious emissions in the Global Positioning System (GPS) radio frequency band that could affect the navigation system of an aircraft. The cell phone in question had, as reported to the FAA (Federal Aviation Administration), caused interference to several GPS receivers on-board a small single engine aircraft despite being compliant with data filed at the time with the FCC by the manufacturer. NASA (National Aeronautics and Space Administration) and industry tests show that while there is an emission in the 1575 MHz GPS band due to a specific combination of amplifier output impedance and load impedance that induces instability in the power amplifier, these spurious emissions (i.e., not the intentional transmit signal) are similar to those measured on non-intentionally transmitting devices such as, for example, laptop computers. Additional testing on a wide sample of different commercial cell phones did not result in any emission in the 1575 MHz GPS Band above the noise floor of the measurement receiver.
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
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
National Aeronautics and Space Administration — NASA is investigating advanced turboelectric aircraft propulsion systems that utilize superconducting motors to drive a number of distributed turbofans....
National Aeronautics and Space Administration — NASA is investigating advanced turboelectric aircraft propulsion systems that utilize superconducting motors to drive a number of distributed turbofans. In an...
Tagge, G. E.; Irish, L. A.; Bailey, A. R.
The results of the Integrated Digital/Electric Aircraft (IDEA) Study are presented. Airplanes with advanced systems were, defined and evaluated, as a means of identifying potential high payoff research tasks. A baseline airplane was defined for comparison, typical of a 1990's airplane with advanced active controls, propulsion, aerodynamics, and structures technology. Trade studies led to definition of an IDEA airplane, with extensive digital systems and electric secondary power distribution. This airplane showed an improvement of 3% in fuel use and 1.8% in DOC relative to the baseline configuration. An alternate configuration, an advanced technology turboprop, was also evaluated, with greater improvement supported by digital electric systems. Recommended research programs were defined for high risk, high payoff areas appropriate for implementation under NASA leadership.
Clinedinst, Winston C.; Slominski, Christopher J.; Dickson, Richard W.; Wolverton, David A.
The individual software processes used in the flight computers on-board the Advanced Transport Operating System (ATOPS) aircraft have many common functional elements. A library of commonly used software modules was created for general uses among the processes. The library includes modules for mathematical computations, data formatting, system database interfacing, and condition handling. The modules available in the library and their associated calling requirements are described.
de Boer, G.; Palo, S.; Argrow, B.; LoDolce, G.; Mack, J.; Gao, R.-S.; Telg, H.; Trussel, C.; Fromm, J.; Long, C. N.; Bland, G.; Maslanik, J.; Schmid, B.; Hock, T.
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 temperature, as might be
G. de Boer
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
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
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
The Lockheed Martin N+2 Low - boom Supersonic Commercial Transport (LSCT) aircraft was optimized in this study through the use of a multidisciplinary design optimization tool developed at the National Aeronautics and S pace Administration Armstrong Flight Research Center. A total of 111 design variables we re used in the first optimization run. Total structural weight was the objective function in this optimization run. Design requirements for strength, buckling, and flutter we re selected as constraint functions during the first optimization run. The MSC Nastran code was used to obtain the modal, strength, and buckling characteristics. Flutter and trim analyses we re based on ZAERO code, and landing and ground control loads were computed using an in - house code. The w eight penalty to satisfy all the design requirement s during the first optimization run was 31,367 lb, a 9.4% increase from the baseline configuration. The second optimization run was prepared and based on the big-bang big-crunch algorithm. Six composite ply angles for the second and fourth composite layers were selected as discrete design variables for the second optimization run. Composite ply angle changes can't improve the weight configuration of the N+2 LSCT aircraft. However, this second optimization run can create more tolerance for the active and near active strength constraint values for future weight optimization runs.
Air data and inertial reference system (ADIRS) is one of the complex sub-system in the aircraft navigation system and it plays an important role into the flight safety of the aircraft. This paper propose an optimize neural network algorithm which is a combination of neural network and ant colony algorithm to improve efficiency of maintenance engineer job task.
Full Text Available The United States is poised to integrate commercial unmanned aircraft systems (UAS into the national airspace and enable government entities to use UAS in a more expedient manner. This policy change, mandated by the Federal Aviation Administration (FAA Modernization and Reform Act of 2012, offers new economic, social and scientific opportunities as well as enhanced law enforcement capacity. However, such benefits will be accompanied by concerns over misuse and abuse of the new technologies by criminals and terrorists. Privacy has been the focus of public debate over the more widespread use of UAS. This paper examines a variety of issues related to allowing broad UAS operations in domestic airspace, and puts forth that safety should be the top priority of policy makers in their effort to integrate UAS into the national airspace system.
João Henrique Lopes Guerra
Full Text Available This is a theoretical-conceptual, which aimed to identify some likely consequences of the integration model systems that have been adopted in the aerospace industry by major aircraft manufacturers in the world. In the model of system integration, these manufacturers maintain internally the activities associated with their basic skills and transfer their skills to peripheral suppliers. We identified the following consequences: the growth of strategic alliances in the airline industry, the internationalization of aeronautical chains, with the strengthening of productive activities in some geographic regions; challenges related to the domestic supplier base and the consolidation of national chains, the greatest power suppliers of the first layer, the contribution to the dissemination of knowledge among supply chains, and the potential emergence of new competitors.
Full Text Available A modelling system for assimilation of CO total columns measured by the IASI/MetOp was developed. The system, based on a sub-optimal Kalman filter coupled with the LMDz-INCA chemistry transport model, allows both assimilating long periods of historical data and making rapid forecasts of the CO concentrations in the middle troposphere based on latest available measurements. Tests of the forecast system were conducted during the international POLARCAT campaigns. A specific treatment that takes into account the representativeness of observations at the scale of the model grid is applied to the IASI CO columns and associated errors before their assimilation in the model. This paper presents the results of assimilation of eight months of historical satellite data measured in 2008. Comparisons of the assimilated CO profiles with independent in situ CO measurements from the MOZAIC program and the POLARCAT aircraft campaigns indicate that the assimilation leads to a considerable improvement of the model simulations in the middle troposphere as compared with a control run with no assimilation. Model biases in the simulation of background values are reduced and improvement in the simulation of very high concentrations is observed. The improvement is due to the transport by the model of the information present in the IASI CO retrievals. The consistency of the improvement contributes to the validation of the IASI CO data.
An aircraft is composed of systems that convert fuel energy to mechanical energy in order to perform work-the movement of people and cargo. Today, the fast-growing demand for air travel has outpaced the rate of improvement in the energy efficiency of aircraft systems. The increase in the total energy consumption and environmental impact of aviation necessitates a strategy to induce further technological and operational innovations to mitigate the increase in aircraft energy use and environmental effects. However, the uncertainty associated with the climate effects of jet engine emissions hinders further improvement to the energy efficiency of aircraft systems. Also the unique characteristics (e.g., trade-off between emissions species) of aircraft systems make it difficult to focus on abatement efforts. Based on a short review of how aircraft technology and operations relate to energy use and the future outlook for aircraft performance, energy use, and environmental impact, the key technology and policy issues related to improving the energy efficiency of aircraft systems are presented. Then, the drivers of technological change in aircraft systems are examined. Government regulation effects and industry characteristics as they relate to improvement of energy use are also presented. Based on these discussions, this paper provides insights on how to accelerate the induction of energy efficient, environmentally friendly innovations.
Lee, Joosung J. [College of Engineering, Yonsei University, Seoul 120-749 (Korea)
An aircraft is composed of systems that convert fuel energy to mechanical energy in order to perform work - the movement of people and cargo. Today, the fast-growing demand for air travel has outpaced the rate of improvement in the energy efficiency of aircraft systems. The increase in the total energy consumption and environmental impact of aviation necessitates a strategy to induce further technological and operational innovations to mitigate the increase in aircraft energy use and environmental effects. However, the uncertainty associated with the climate effects of jet engine emissions hinders further improvement to the energy efficiency of aircraft systems. Also the unique characteristics (e.g., trade-off between emissions species) of aircraft systems make it difficult to focus on abatement efforts. Based on a short review of how aircraft technology and operations relate to energy use and the future outlook for aircraft performance, energy use, and environmental impact, the key technology and policy issues related to improving the energy efficiency of aircraft systems are presented. Then, the drivers of technological change in aircraft systems are examined. Government regulation effects and industry characteristics as they relate to improvement of energy use are also presented. Based on these discussions, this paper provides insights on how to accelerate the induction of energy efficient, environmentally friendly innovations. (author)
Sodemann, H.; Pommier, M.; Arnold, S. R.; Monks, S. A.; Stebel, K.; Burkhart, J. F.; Hair, J. W.; Diskin, G. S.; Clerbaux, C.; Coheur, P.-F.; Hurtmans, D.; Schlager, H.; Blechschmidt, A.-M.; Kristjansson, J. E.; Stohl, A.
During the POLARCAT summer campaign in 2008, two episodes (2 5 July and 7 10 July 2008) occurred where low-pressure systems traveled from Siberia across the Arctic Ocean towards the North Pole. The two cyclones had extensive smoke plumes from Siberian forest fires and anthropogenic sources in East Asia embedded in their associated air masses, creating an excellent opportunity to use satellite and aircraft observations to validate the performance of atmospheric transport models in the Arctic, which is a challenging model domain due to numerical and other complications. Here we compare transport simulations of carbon monoxide (CO) from the Lagrangian transport model FLEXPART and the Eulerian chemical transport model TOMCAT with retrievals of total column CO from the IASI passive infrared sensor onboard the MetOp-A satellite. The main aspect of the comparison is how realistic horizontal and vertical structures are represented in the model simulations. Analysis of CALIPSO lidar curtains and in situ aircraft measurements provide further independent reference points to assess how reliable the model simulations are and what the main limitations are. The horizontal structure of mid-latitude pollution plumes agrees well between the IASI total column CO and the model simulations. However, finer-scale structures are too quickly diffused in the Eulerian model. Applying the IASI averaging kernels to the model data is essential for a meaningful comparison. Using aircraft data as a reference suggests that the satellite data are biased high, while TOMCAT is biased low. FLEXPART fits the aircraft data rather well, but due to added background concentrations the simulation is not independent from observations. The multi-data, multi-model approach allows separating the influences of meteorological fields, model realisation, and grid type on the plume structure. In addition to the very good agreement between simulated and observed total column CO fields, the results also highlight the
Bridgelall, Raj; Rafert, J. B.; Atwood, Don; Tolliver, Denver D.
Transportation agencies expend significant resources to inspect critical infrastructure such as roadways, railways, and pipelines. Regular inspections identify important defects and generate data to forecast maintenance needs. However, cost and practical limitations prevent the scaling of current inspection methods beyond relatively small portions of the network. Consequently, existing approaches fail to discover many high-risk defect formations. Remote sensing techniques offer the potential for more rapid and extensive non-destructive evaluations of the multimodal transportation infrastructure. However, optical occlusions and limitations in the spatial resolution of typical airborne and space-borne platforms limit their applicability. This research proposes hyperspectral image classification to isolate transportation infrastructure targets for high-resolution photogrammetric analysis. A plenoptic swarm of unmanned aircraft systems will capture images with centimeter-scale spatial resolution, large swaths, and polarization diversity. The light field solution will incorporate structure-from-motion techniques to reconstruct three-dimensional details of the isolated targets from sequences of two-dimensional images. A comparative analysis of existing low-power wireless communications standards suggests an application dependent tradeoff in selecting the best-suited link to coordinate swarming operations. This study further produced a taxonomy of specific roadway and railway defects, distress symptoms, and other anomalies that the proposed plenoptic swarm sensing system would identify and characterize to estimate risk levels.
Price, M.; Raghunathan, S.; Curran, R.
The challenge in Aerospace Engineering, in the next two decades as set by Vision 2020, is to meet the targets of reduction of nitric oxide emission by 80%, carbon monoxide and carbon dioxide both by 50%, reduce noise by 50% and of course with reduced cost and improved safety. All this must be achieved with expected increase in capacity and demand. Such a challenge has to be in a background where the understanding of physics of flight has changed very little over the years and where industrial growth is driven primarily by cost rather than new technology. The way forward to meet the challenges is to introduce innovative technologies and develop an integrated, effective and efficient process for the life cycle design of aircraft, known as systems engineering (SE). SE is a holistic approach to a product that comprises several components. Customer specifications, conceptual design, risk analysis, functional analysis and architecture, physical architecture, design analysis and synthesis, and trade studies and optimisation, manufacturing, testing validation and verification, delivery, life cycle cost and management. Further, it involves interaction between traditional disciplines such as Aerodynamics, Structures and Flight Mechanics with people- and process-oriented disciplines such as Management, Manufacturing, and Technology Transfer. SE has become the state-of-the-art methodology for organising and managing aerospace production. However, like many well founded methodologies, it is more difficult to embody the core principles into formalised models and tools. The key contribution of the paper will be to review this formalisation and to present the very latest knowledge and technology that facilitates SE theory. Typically, research into SE provides a deeper understanding of the core principles and interactions, and helps one to appreciate the required technical architecture for fully exploiting it as a process, rather than a series of events. There are major issues as
Full Text Available The authors earlier model for the vulnerability of aircraft where aircraft was considered as a combination of cylinder, cones and wedges has been extended to the case when structural data of aircraft as well as its vital parts are given in the form of three-dimensional curvilinear triangles. In the case of VT -fused ammunition, spherical normal distribution has been used to estimate the landing probability of the shell in a cylindrical vicinity region around the aircraft. Kill criteria of vital parts have been redefined.
National Aeronautics and Space Administration — Diagnostic and prognostic algorithms for many aircraft subsystems are steadily maturing. Unfortunately there is little experience integrating these technologies...
National Aeronautics and Space Administration — Aircraft design is a complex process requiring interactions and exchange of information among multiple disciplines such as aerodynamics, strength, fatigue,...
This volume contains input data and parameters used in the model of the transportation sector of the National Energy Modeling System. The list of Transportation Sector Model variables includes parameters for the following: Light duty vehicle modules (fuel economy, regional sales, alternative fuel vehicles); Light duty vehicle stock modules; Light duty vehicle fleet module; Air travel module (demand model and fleet efficiency model); Freight transport module; Miscellaneous energy demand module; and Transportation emissions module. Also included in these appendices are: Light duty vehicle market classes; Maximum light duty vehicle market penetration parameters; Aircraft fleet efficiency model adjustment factors; and List of expected aircraft technology improvements.
This final report has been prepared by Honeywell Engines & Systems, Phoenix, Arizona, a unit of Honeywell International Inc., documenting work performed during the period June 1999 through December 1999 for the National Aeronautics and Space Administration (NASA) Glenn Research Center, Cleveland, Ohio, under the Small Engine Technology (SET) Program, Contract No. NAS3-27483, Task Order 24, Business and Regional Aircraft System Studies. The work performed under SET Task 24 consisted of evaluating the noise reduction benefits compared to the baseline noise levels of representative 1992 technology aircraft, obtained by applying different combinations of noise reduction technologies to five business and regional aircraft configurations. This report focuses on the selection of the aircraft configurations and noise reduction technologies, the prediction of noise levels for those aircraft, and the comparison of the noise levels with those of the baseline aircraft.
Moses, C. A.
Problems of ensuring compatibility of Navy aircraft with fuels that may be different than the fuels for which the equipment was designed and qualified are discussed. To avoid expensive requalification of all the engines and airframe fuel systems, methodologies to qualify future fuels by using bench-scale and component testing are being sought. Fuel blends with increasing JP5-type aromatic concentration were seen to produce less volume swell than an equivalent aromatic concentration in the reference fuel. Futhermore, blends with naphthenes, decalin, tetralin, and naphthalenes do not deviate significantly from the correlation line of aromatic blends, Similar results are found with tensile strenth and elongation. Other elastomers, sealants, and adhesives are also being tested.
The aim of this paper is to give an overview of recent research, development and civil application of remotely piloted aircraft systems (RPAS) in Europe. It describes a European strategy for the development of civil applications of Remotely Piloted Aircraft Systems (RPAS) and reflects most of the contents of the European staff working document SWD(2012) 259 final.
Andrieu, Christian W.
Aircraft maintenance control operates in a dynamic, high intensity environment. Maintenance work priorities are made several times daily under extremely demanding and time sensitive conditions. the person responsible for scheduling aircraft, usually the Maintenance Master Chief, draws upon years of experience when assigning priorities for both scheduled and unscheduled maintenance. An Expert System Advisor for Aircraft Maintenance Scheduling (ESAAMS) is being implemented at the Naval Postg...
Belcastro, Christine M.; Jacobson, Steven r.
Loss of control remains one of the largest contributors to aircraft fatal accidents worldwide. Aircraft loss-of-control accidents are highly complex in that they can result from numerous causal and contributing factors acting alone or (more often) in combination. Hence, there is no single intervention strategy to prevent these accidents. This paper presents future system concepts and research directions for preventing aircraft loss-of-control accidents.