Activation Product Inverse Calculations with NDI

Energy Technology Data Exchange (ETDEWEB)

Gray, Mark Girard [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

2017-09-27

NDI based forward calculations of activation product concentrations can be systematically used to infer structural element concentrations from measured activation product concentrations with an iterative algorithm. The algorithm converges exactly for the basic production-depletion chain with explicit activation product production and approximately, in the least-squares sense, for the full production-depletion chain with explicit activation product production and nosub production-depletion chain. The algorithm is suitable for automation.

Narva kant vajab oma brändi / Esko Passila

Index Scriptorium Estoniae

Passila, Esko

2007-01-01

Autor leiab, et Ida-Virumaa peaks looma ühtse tugeva brändi, mille alusel tulevikuotsuseid teha. See peaks tooma välja soodsa asukoha eelised, võimalused, tööjõu kättesaadavuse, kasutusvalmid maa-alad, hinnad jne.

Lithium-induced NDI: acetazolamide reduces polyuria but does not improve urine concentrating ability.

Science.gov (United States)

de Groot, Theun; Doornebal, Joan; Christensen, Birgitte M; Cockx, Simone; Sinke, Anne P; Baumgarten, Ruben; Bedford, Jennifer J; Walker, Robert J; Wetzels, Jack F M; Deen, Peter M T

2017-09-01

Lithium is the mainstay treatment for patients with bipolar disorder, but it generally causes nephrogenic diabetes insipidus (NDI), a disorder in which the renal urine concentrating ability has become vasopressin insensitive. Li-NDI is caused by lithium uptake by collecting duct principal cells and downregulation of aquaporin-2 (AQP2) water channels, which are essential for water uptake from tubular urine. Recently, we found that the prophylactic administration of acetazolamide to mice effectively attenuated Li-NDI. To evaluate whether acetazolamide might benefit lithium-treated patients, we administered acetazolamide to mice with established Li-NDI and six patients with a lithium-induced urinary concentrating defect. In mice, acetazolamide partially reversed lithium-induced polyuria and increased urine osmolality, which, however, did not coincide with increased AQP2 abundances. In patients, acetazolamide led to the withdrawal of two patients from the study due to side effects. In the four remaining patients acetazolamide did not lead to clinically relevant changes in maximal urine osmolality. Urine output was also not affected, although none of these patients demonstrated overt lithium-induced polyuria. In three out of four patients, acetazolamide treatment increased serum creatinine levels, indicating a decreased glomerular filtration rate (GFR). Strikingly, these three patients also showed a decrease in systemic blood pressure. All together, our data reveal that acetazolamide does not improve the urinary concentrating defect caused by lithium, but it lowers the GFR, likely explaining the reduced urine output in our mice and in a recently reported patient with lithium-induced polyuria. The reduced GFR in patients prone to chronic kidney disease development, however, warrants against application of acetazolamide in Li-NDI patients without long-term (pre)clinical studies. Copyright © 2017 the American Physiological Society.

NASGRO 3.0: A Software for Analyzing Aging Aircraft

Science.gov (United States)

Mettu, S. R.; Shivakumar, V.; Beek, J. M.; Yeh, F.; Williams, L. C.; Forman, R. G.; McMahon, J. J.; Newman, J. C., Jr.

1999-01-01

Structural integrity analysis of aging aircraft is a critical necessity in view of the increasing numbers of such aircraft in general aviation, the airlines and the military. Efforts are in progress by NASA, the FAA and the DoD to focus attention on aging aircraft safety. The present paper describes the NASGRO software which is well-suited for effectively analyzing the behavior of defects that may be found in aging aircraft. The newly revised Version 3.0 has many features specifically implemented to suit the needs of the aircraft community. The fatigue crack growth computer program NASA/FLAGRO 2.0 was originally developed to analyze space hardware such as the Space Shuttle, the International Space Station and the associated payloads. Due to popular demand, the software was enhanced to suit the needs of the aircraft industry. Major improvements in Version 3.0 are the incorporation of the ability to read aircraft spectra of unlimited size, generation of common aircraft fatigue load blocks, and the incorporation of crack-growth models which include load-interaction effects such as retardation due to overloads and acceleration due to underloads. Five new crack-growth models, viz., generalized Willenborg, modified generalized Willenborg, constant closure model, Walker-Chang model and the deKoning-Newman strip-yield model, have been implemented. To facilitate easier input of geometry, material properties and load spectra, a Windows-style graphical user interface has been developed. Features to quickly change the input and rerun the problem as well as examine the output are incorporated. NASGRO has been organized into three modules, the crack-growth module being the primary one. The other two modules are the boundary element module and the material properties module. The boundary-element module provides the ability to model and analyze complex two-dimensional problems to obtain stresses and stress-intensity factors. The material properties module allows users to store and

A new nidovirus (NamDinh virus NDiV): Its ultrastructural characterization in the C6/36 mosquito cell line

Energy Technology Data Exchange (ETDEWEB)

Thuy, Nguyen Thanh, E-mail: ngtthuy02@yahoo.com [National Institute of Hygiene and Epidemiology, 1 Yersin Street, Hai Ba Trung District, Hanoi (Viet Nam); Huy, Tran Quang, E-mail: huytq@nihe.org.vn [National Institute of Hygiene and Epidemiology, 1 Yersin Street, Hai Ba Trung District, Hanoi (Viet Nam); Nga, Phan Thi [National Institute of Hygiene and Epidemiology, 1 Yersin Street, Hai Ba Trung District, Hanoi (Viet Nam); Morita, Kouichi [Department of Virology, Institute of Tropical Medicine, Global COE Program, Nagasaki University, Nagasaki (Japan); Dunia, Irene; Benedetti, Lucio [Institut Jacques Monod, UMR7592 Université Paris Diderot/CNRS, Paris (France)

2013-09-15

We describe the ultrastructure of the NamDinh virus (NDiV), a new member of the order Nidovirales grown in the C6/36 mosquito cell line. Uninfected and NDiV-infected cells were investigated by electron microscopy 24–48 h after infection. The results show that the viral nucleocapsid-like particles form clusters concentrated in the vacuoles, the endoplasmic reticulum, and are scattered in the cytoplasm. Mature virions of NDiV were released as budding particles on the cell surface where viral components appear to lie beneath and along the plasma membrane. Free homogeneous virus particles were obtained by ultracentrifugation on sucrose gradients of culture fluids. The size of the round-shaped particles with a complete internal structure was 80 nm in diameter. This is the first study to provide information on the morphogenesis and ultrastructure of the first insect nidovirus NDiV, a missing evolutionary link in the emergence of the viruses with the largest RNA genomes. - Highlights: • NamDinh virus (NDiV), a new member of the order Nidovirales was tested in cultured cell line. • The morphogenesis and ultrastructure of NDiV were investigated by electron microscopy. • The viral nucleocapsid-like particles clustered and scattered in the cytoplasm. • NDiVs were released as budding particles on the cell surface. • The size of the viral particles with a complete internal structure was 80 nm in diameter.

Smart aircraft fastener evaluation (SAFE) system: a condition-based corrosion detection system for aging aircraft

Science.gov (United States)

Schoess, Jeffrey N.; Seifert, Greg; Paul, Clare A.

1996-05-01

The smart aircraft fastener evaluation (SAFE) system is an advanced structural health monitoring effort to detect and characterize corrosion in hidden and inaccessible locations of aircraft structures. Hidden corrosion is the number one logistics problem for the U.S. Air Force, with an estimated maintenance cost of $700M per year in 1990 dollars. The SAFE system incorporates a solid-state electrochemical microsensor and smart sensor electronics in the body of a Hi-Lok aircraft fastener to process and autonomously report corrosion status to aircraft maintenance personnel. The long-term payoff for using SAFE technology will be in predictive maintenance for aging aircraft and rotorcraft systems, fugitive emissions applications such as control valves, chemical pipeline vessels, and industrial boilers. Predictive maintenance capability, service, and repair will replace the current practice of scheduled maintenance to substantially reduce operational costs. A summary of the SAFE concept, laboratory test results, and future field test plans is presented.

The Ages and Stages Questionnaire and Neurodevelopmental Impairment in Two-Year-Old Preterm-Born Children.

Directory of Open Access Journals (Sweden)

Jorien M Kerstjens

Full Text Available To test the ability of the Ages and Stages Questionnaire, Third Edition (ASQ3 to help identify or exclude neurodevelopmental impairment (NDI in very preterm-born children at the corrected age of two.We studied the test results of 224 children, born at <32 postmenstrual weeks, who had scores on ASQ3 and Bayley Scales of Infant and Toddler Development, Third Edition (BSIDIII and neurological examination at 22-26 months' corrected age. We defined NDI as a score of <70 on the cognitive--or motor composite scale of BSIDIII, or impairment on neurological examination or audiovisual screening. We compared NDI with abnormal ASQ3 scores, i.e., < -2SDs on any domain, and with ASQ3 total scores. To correct for possible overestimation of BSIDIII, we also analyzed the adjusted BSIDIII thresholds for NDI, i.e., scores <80 and <85.We found 61 (27% children with abnormal ASQ3 scores, and 10 (4.5% children who had NDI with original BSIDIII thresholds (<70. Twelve children had NDI at BSIDIII thresholds at <80, and 15 had <85. None of the 163 (73% children who passed ASQ3 had NDI. The sensitivity of ASQ3 to detect NDI was excellent (100%, its specificity was acceptable (76%, and its negative predictive value (NPV was 100%. Sensitivity and NPV remained high with the adjusted BSIDIII thresholds.The Ages and Stages Questionnaire is a simple, valid and cost-effective screening tool to help identify and exclude NDI in very preterm-born children at the corrected age of two years.

NDI (Nondestructive Inspection) Oriented Corrosion Control for Army Aircraft. Phase 1. Inspection Methods

Science.gov (United States)

1989-07-01

Appendices A and B and are provided as cover sheets from each item rather than completc packages. The Pamplet Series materials were furnished as camera-ready...34Stational Neutron Radiography System for Aircraft Reliability and Maintainability." G. A. Technologies Brochure , Triga Reactor Division, San Diego

Genetic forms of nephrogenic diabetes insipidus (NDI): Vasopressin receptor defect (X-linked) and aquaporin defect (autosomal recessive and dominant).

Science.gov (United States)

Bichet, Daniel G; Bockenhauer, Detlef

2016-03-01

Nephrogenic diabetes insipidus (NDI), which can be inherited or acquired, is characterized by an inability to concentrate urine despite normal or elevated plasma concentrations of the antidiuretic hormone, arginine vasopressin (AVP). Polyuria with hyposthenuria and polydipsia are the cardinal clinical manifestations of the disease. About 90% of patients with congenital NDI are males with X-linked NDI who have mutations in the vasopressin V2 receptor (AVPR2) gene encoding the vasopressin V2 receptor. In less than 10% of the families studied, congenital NDI has an autosomal recessive or autosomal dominant mode of inheritance with mutations in the aquaporin-2 (AQP2) gene. When studied in vitro, most AVPR2 and AQP2 mutations lead to proteins trapped in the endoplasmic reticulum and are unable to reach the plasma membrane. Prior knowledge of AVPR2 or AQP2 mutations in NDI families and perinatal mutation testing is of direct clinical value and can avert the physical and mental retardation associated with repeated episodes of dehydration. Copyright © 2016 Elsevier Ltd. All rights reserved.

Sildenafil reduces polyuria in rats with lithium-induced NDI.

Science.gov (United States)

Sanches, Talita Rojas; Volpini, Rildo Aparecido; Massola Shimizu, Maria H; Bragança, Ana Carolina de; Oshiro-Monreal, Fabíola; Seguro, Antonio Carlos; Andrade, Lúcia

2012-01-01

Lithium (Li)-treated patients often develop urinary concentrating defect and polyuria, a condition known as nephrogenic diabetes insipidus (NDI). In a rat model of Li-induced NDI, we studied the effect that sildenafil (Sil), a phosphodiesterase 5 (PDE5) inhibitor, has on renal expression of aquaporin-2 (AQP2), urea transporter UT-A1, Na(+)/H(+) exchanger 3 (NHE3), Na(+)-K(+)-2Cl(-) cotransporter (NKCC2), epithelial Na channel (ENaC; α-, β-, and γ-subunits), endothelial nitric oxide synthase (eNOS), and inducible nitric oxide synthase. We also evaluated cGMP levels in medullary collecting duct cells in suspension. For 4 wk, Wistar rats received Li (40 mmol/kg food) or no treatment (control), some receiving, in weeks 2-4, Sil (200 mg/kg food) or Li and Sil (Li+Sil). In Li+Sil rats, urine output and free water clearance were markedly lower, whereas urinary osmolality was higher, than in Li rats. The cGMP levels in the suspensions of medullary collecting duct cells were markedly higher in the Li+Sil and Sil groups than in the control and Li groups. Semiquantitative immunoblotting revealed the following: in Li+Sil rats, AQP2 expression was partially normalized, whereas that of UT-A1, γ-ENaC, and eNOS was completely normalized; and expression of NKCC2 and NHE3 was significantly higher in Li rats than in controls. Inulin clearance was normal in all groups. Mean arterial pressure and plasma arginine vasopressin did not differ among the groups. Sil completely reversed the Li-induced increase in renal vascular resistance. We conclude that, in experimental Li-induced NDI, Sil reduces polyuria, increases urinary osmolality, and decreases free water clearance via upregulation of renal AQP2 and UT-A1.

Successful amelioration of mitochondrial optic neuropathy using the yeast NDI1 gene in a rat animal model.

Directory of Open Access Journals (Sweden)

Mathieu Marella

2010-07-01

Full Text Available Leber's hereditary optic neuropathy (LHON is a maternally inherited disorder with point mutations in mitochondrial DNA which result in loss of vision in young adults. The majority of mutations reported to date are within the genes encoding the subunits of the mitochondrial NADH-quinone oxidoreductase, complex I. Establishment of animal models of LHON should help elucidate mechanism of the disease and could be utilized for possible development of therapeutic strategies.We established a rat model which involves injection of rotenone-loaded microspheres into the optic layer of the rat superior colliculus. The animals exhibited the most common features of LHON. Visual loss was observed within 2 weeks of rotenone administration with no apparent effect on retinal ganglion cells. Death of retinal ganglion cells occurred at a later stage. Using our rat model, we investigated the effect of the yeast alternative NADH dehydrogenase, Ndi1. We were able to achieve efficient expression of the Ndi1 protein in the mitochondria of all regions of retinal ganglion cells and axons by delivering the NDI1 gene into the optical layer of the superior colliculus. Remarkably, even after the vision of the rats was severely impaired, treatment of the animals with the NDI1 gene led to a complete restoration of the vision to the normal level. Control groups that received either empty vector or the GFP gene had no effects.The present study reports successful manifestation of LHON-like symptoms in rats and demonstrates the potential of the NDI1 gene therapy on mitochondrial optic neuropathies. Our results indicate a window of opportunity for the gene therapy to be applied successfully after the onset of the disease symptoms.

2. november tähistas Eesti ekstreem-metal-skene jaoks kahe äärmiselt olulise üllitise taassündi

Index Scriptorium Estoniae

2009-01-01

Nailboard Records üllitas pagan-metal-bändi Tharaphita albumi "Raev" digipack-CD, millele on lisatud 1996. aastal ilmunud neljalooline demosalvestis "Kui varjud põlevad" ja dark-elektro-bändi Forgotten Sunrise demo "Behind The Abysmal Sky" (1993) ning minialbumi "Forever Sleeping Greystones" (1994) lood

Broadband polarized emission from P(NDI2OD-T2) polymer.

Science.gov (United States)

Ulrich, Steve; Sutch, Tabitha; Szulczewski, Greg; Schweizer, Matthias; Barbosa, Newton; Araujo, Paulo

2018-05-18

We investigate the P(NDI2OD-T2) photophysical properties via absorbance and fluorescence spectroscopy, in association with the experimental approach baptized Stokes Spectroscopy, which provides valuable material information through the acquisition and analysis of the fluorescence polarization degree. By changing solvents and using different samples such as solutions, thick, and thin films, it is possible to control the polarization degree spectrum associated to the fluorescence emitted by the polymer's isolated chains and aggregates. We show that the polarization degree could become a powerful tool to obtain information related to the samples morphology, which is connected to their microscopic structure. Moreover, the polarization degree spectra suggest that depolarization effects linked to energy and charge transfer mechanisms are likely taking place. Our findings indicate that P(NDI2OD-T2) polymers are excellent candidates for the advancement of organic technologies that rely on the emission and detection of polarized lights. © 2018 IOP Publishing Ltd.

Economic aspects of hydro geological risk mitigation measures management in Italy: the ReNDiS project experience

Science.gov (United States)

Spizzichino, D.; Campobasso, C.; Gallozzi, P. L.; Dessi', B.; Traversa, F.

2009-04-01

ReNDiS project is a useful tool for monitoring, analysis and management of information data on mitigation measures and restoration works of soil protection at national scale. The main scope of the project, and related monitoring activities, is to improve the knowledge about the use of national funds and efforts against floods and landslides risk and, as a consequence, to better address the preventive policies in future. Since 1999 after the disastrous mudflow event occurred in Sarno in 1998, which caused the loss of 160 human lives, an extraordinary effort was conducted by the Italian Government in order to promote preventive measures against the hydro geological risk over the entire Italian territory. The Italian Ministry for the Environment promoted several and annual soil protection programmes. The ReNDiS project (Repertory of mitigation measures for National Soil Protection) is carried out by ISPRA - Institute for Environmental protection and Research, with the aim of improving the knowledge about the results of preventive policies against floods and landslides in order to better address national funds as requested by the Minister itself. The repertory is composed by a main archive and two secondary interface, the first for direct data management (ReNDiS-ist) and the latter (ReNDiS-web) for the on-line access and public consultation. At present, ReNDiS database contains about 3000 records concerning those programmes, focused on restoration works but including also information on landslide typologies and processes. The monitoring project is developed taking into account all the information about each step of every mitigation measure from the initial funding phase until the end of the work. During present work, we have statistically analyzed the ReNDiS database in order to highlight the conformity between the characteristic and type of the hazard (identified in a specific area) and the corresponding mitigation measures adopted for risk reduction. Through specific

Caenorhabditis elegans expressing the Saccharomyces cerevisiae NADH alternative dehydrogenase Ndi1p, as a tool to identify new genes involved in complex I related diseases

Directory of Open Access Journals (Sweden)

Raynald eCossard

2015-06-01

Full Text Available Isolated complex I deficiencies are one of the most commonly observed biochemical features in patients suffering from mitochondrial disorders. In the majority of these clinical cases the molecular bases of the diseases remain unknown suggesting the involvement of unidentified factors that are critical for complex I function.The Saccharomyces cerevisiae NDI1 gene, encoding the mitochondrial internal NADH dehydrogenase was previously shown to complement a complex I deficient strain in Caenorhabitis elegans with notable improvements in reproduction, whole organism respiration. These features indicate that Ndi1p can functionally integrate the respiratory chain, allowing complex I deficiency complementation. Taking into account the Ndi1p ability to bypass complex I, we evaluate the possibility to extend the range of defects/mutations causing complex I deficiencies that can be alleviated by NDI1 expression.We report here that NDI1 expressing animals unexpectedly exhibit a slightly shortened lifespan, a reduction in the progeny and a depletion of the mitochondrial genome. However, Ndi1p is expressed and targeted to the mitochondria as a functional protein that confers rotenone resistance to those animals and without affecting their respiration rate and ATP content.We show that the severe embryonic lethality level caused by the RNAi knockdowns of complex I structural subunit encoding genes (e.g. NDUFV1, NDUFS1, NDUFS6, NDUFS8 or GRIM-19 human orthologs in wild type animals is significantly reduced in the Ndi1p expressing worm.All together these results open up the perspective to identify new genes involved in complex I function, assembly or regulation by screening an RNAi library of genes leading to embryonic lethality that should be rescued by NDI1 expression.

The Second Joint NASA/FAA/DOD Conference on Aging Aircraft. Pt. 1

Science.gov (United States)

Harris, Charles E. (Editor)

1999-01-01

The purpose of the Conference was to bring together world leaders in aviation safety research, aircraft design and manufacturing, fleet operation and aviation maintenance to disseminate information on current practices and advanced technologies that will assure the continued airworthiness of the aging aircraft in the military and commercial fleets. The Conference included reviews of current industry practices, assessments of future technology requirements, and status of aviation safety research. The Conference provided an opportunity for interactions among the key personnel in the research and technology development community, the original equipment manufacturers, commercial airline operators, military fleet operators, aviation maintenance, and aircraft certification and regulatory authorities. Conference participation was unrestricted and open to the international aviation community.

Fatigue damage assessment of high-usage in-service aircraft fuselage structure

Science.gov (United States)

Mosinyi, Bao Rasebolai

As the commercial and military aircraft fleets continue to age, there is a growing concern that multiple-site damage (MSD) can compromise structural integrity. Multiple site damage is the simultaneous occurrence of many small cracks at independent structural locations, and is the natural result of fatigue, corrosion, fretting and other possible damage mechanisms. These MSD cracks may linkup and form a fatigue lead crack of critical length. The presence of MSD also reduces the structure's ability to withstand longer cracks. The objective of the current study is to assess, both experimentally and analytically, MSD formation and growth in the lap joint of curved panels removed from a retired aircraft. A Boeing 727-232 airplane owned and operated by Delta Air Lines, and retired at its design service goal, was selected for the study. Two panels removed from the left-hand side of the fuselage crown, near stringer 4L, were subjected to extended fatigue testing using the Full-Scale Aircraft Structural Test Evaluation and Research (FASTER) facility located at the Federal Aviation Administration (FAA) William J. Hughes Technical Center. The state of MSD was continuously assessed using several nondestructive inspection (NDI) methods. Damage to the load attachment points of the first panel resulted in termination of the fatigue test at 43,500 fatigue cycles, before cracks had developed in the lap joint. The fatigue test for the second panel was initially conducted under simulated in-service loading conditions for 120,000 cycles, and no cracks were detected in the skin of the panel test section. Artificial damage was then introduced into the panel at selected rivets in the critical (lower) rivet row, and the fatigue loads were increased. Visually detectable crack growth from the artificial notches was first seen after 133,000 cycles. The resulting lead crack grew along the lower rivet row, eventually forming an 11.8" long unstable crack after 141,771 cycles, at which point the

A look at the ASEAN-NDI: building a regional health R&D innovation network.

Science.gov (United States)

Montoya, Jaime C; Rebulanan, Carina L; Parungao, Nico Angelo C; Ramirez, Bernadette

2014-01-01

Globally, there are growing efforts to address diseases through the advancement in health research and development (R&D), strengthening of regional cooperation in science and technology (particularly on product discovery and development), and implementation of the World Health Assembly Resolution 61.21 (WHA61.21) on the Global Strategy and Plan of Action on Public Health, Innovation, and Intellectual Property (GSPA-PHI). As such, the Association of Southeast Asian Nations (ASEAN) is responding to this through the establishment of the ASEAN-Network for Drugs, Diagnostics, Vaccines, and Traditional Medicines Innovation (ASEAN-NDI). This is important in the ASEAN considering that infectious tropical diseases remain prevalent, emerging, and reemerging in the region. This paper looks into the evolution of the ASEAN-NDI from its inception in 2009, to how it is at present, and its plans to mitigate public health problems regionally and even globally.

A Tool Measuring Remaining Thickness of Notched Acoustic Cavities in Primary Reaction Control Thruster NDI Standards

Science.gov (United States)

Sun, Yushi; Sun, Changhong; Zhu, Harry; Wincheski, Buzz

2006-01-01

Stress corrosion cracking in the relief radius area of a space shuttle primary reaction control thruster is an issue of concern. The current approach for monitoring of potential crack growth is nondestructive inspection (NDI) of remaining thickness (RT) to the acoustic cavities using an eddy current or remote field eddy current probe. EDM manufacturers have difficulty in providing accurate RT calibration standards. Significant error in the RT values of NDI calibration standards could lead to a mistaken judgment of cracking condition of a thruster under inspection. A tool based on eddy current principle has been developed to measure the RT at each acoustic cavity of a calibration standard in order to validate that the standard meets the sample design criteria.

An artificial intelligence-based structural health monitoring system for aging aircraft

Science.gov (United States)

Grady, Joseph E.; Tang, Stanley S.; Chen, K. L.

1993-01-01

To reduce operating expenses, airlines are now using the existing fleets of commercial aircraft well beyond their originally anticipated service lives. The repair and maintenance of these 'aging aircraft' has therefore become a critical safety issue, both to the airlines and the Federal Aviation Administration. This paper presents the results of an innovative research program to develop a structural monitoring system that will be used to evaluate the integrity of in-service aerospace structural components. Currently in the final phase of its development, this monitoring system will indicate when repair or maintenance of a damaged structural component is necessary.

Development of a NDI system using the magneto-optical method. 2. Remote sensing using the novel magneto-optical inspection system

International Nuclear Information System (INIS)

Lee, Jinyi; Shoji, Tetsuo

1999-01-01

A new remote sensing system using the magneto-optical method is developed for inspection of flaws introduced during service operation where routine inspection is difficult because of difficult inaccessibility to the components. Among the advantages of non-destructive inspection (NDI) based on the magneto-optical sensor are: real time inspection, elimination of electrical noise and high spatial resolution. Remote sensing of flaws is achieved using the basic principles of Faraday effect, optical permeability, and diffraction of a laser by the domain walls. This paper describes a novel remote NDI system using the principles of optics and LMF. The main characteristic of the system is that image data and LMF information can be obtained simultaneously. It is possible to carry out remote and high speed inspection of cracks from the intensity of reflected light, and to estimate the size of a crack effectively with their diverse data. The advantages of this NDI system are demonstrated using two specimens. (author)

Integration of structural health monitoring solutions onto commercial aircraft via the Federal Aviation Administration structural health monitoring research program

Science.gov (United States)

Swindell, Paul; Doyle, Jon; Roach, Dennis

2017-02-01

The Federal Aviation Administration (FAA) started a research program in structural health monitoring (SHM) in 2011. The program's goal was to understand the technical gaps of implementing SHM on commercial aircraft and the potential effects on FAA regulations and guidance. The program evolved into a demonstration program consisting of a team from Sandia National Labs Airworthiness Assurance NDI Center (AANC), the Boeing Corporation, Delta Air Lines, Structural Monitoring Systems (SMS), Anodyne Electronics Manufacturing Corp (AEM) and the FAA. This paper will discuss the program from the selection of the inspection problem, the SHM system (Comparative Vacuum Monitoring-CVM) that was selected as the inspection solution and the testing completed to provide sufficient data to gain the first approved use of an SHM system for routine maintenance on commercial US aircraft.

The Second Joint NASA/FAA/DoD Conference on Aging Aircraft. Part 2

Science.gov (United States)

Harris, Charles E. (Editor)

1999-01-01

The purpose of the Conference was to bring together world leaders in aviation safety research, aircraft design and manufacturing, fleet operation and aviation maintenance to disseminate information on current practices and advanced technologies that will assure the continued airworthiness of the aging aircraft in the military and commercial fleets. The Conference included reviews of current industry practices, assessments of future technology requirements, and status of aviation safety research. The Conference provided an opportunity for interactions among the key personnel in the research and technology development community, the original equipment manufacturers, commercial airline operators, military fleet operators, aviation maintenance, and aircraft certification and regulatory authorities. Conference participation was unrestricted and open to the international aviation community. Appendix B contains the name and addresses of the 623 participants in the Conference.

Brändi näkyy musiikkivideossa : Esimerkkitapaus Michael Jackson

OpenAIRE

Kontinen, Noora

2016-01-01

Tutkin opinnäytetyössäni brändin ja musiikkivideon suhdetta toisiinsa. Työssä käsitellään lyhyesti myös tähteyttä. Esittelen ensin vähän historiaa ja peruskäsitteitä, minkä jälkeen käytän Michael Jacksonin Billie Jean -musiikkivideota esimerkkinä tutkiessani Michael Jacksonin brändiä. Teoksessa käytetään lähdeaineistoa sekä omaa analyysia. Keskityn tarkastelemaan musiikkivideoita, ja niihin liittyviä sisältöjä yleisesti, ei niinkään teknisesti. Toivon, että työstäni on apua jollekin,...

Uudised : Vanemuise Sümfoonikute kontsert. Kaks õhtut TMMis. Esimene puhkpilli- ja bigbändiõhtu / Jaanika Juhanson

Index Scriptorium Estoniae

Juhanson, Jaanika, 1977-

2000-01-01

Eelinfo 11. märtsil toimuva Vanemuise Sümfoonikute kontserdi kohta Vanemuise kontserdimajas. M. Korjuse vitriini avamisest 23. veebr. Teatri- ja Muusikamuuseumis, D. Kokkeri mälestusõhtust 29. veebr. TMMi Assauwe tornis. 4. märtsil EMA saalis toimunud puhkpilliorkestri ja bigbändi kontserdist

Development of an ultrasonic nondestructive inspection method for impact damage detection in composite aircraft structures

Science.gov (United States)

Capriotti, M.; Kim, H. E.; Lanza di Scalea, F.; Kim, H.

2017-04-01

High Energy Wide Area Blunt Impact (HEWABI) due to ground service equipment can often occur in aircraft structures causing major damages. These Wide Area Impact Damages (WAID) can affect the internal components of the structure, hence are usually not visible nor detectable by typical one-sided NDE techniques and can easily compromise the structural safety of the aircraft. In this study, the development of an NDI method is presented together with its application to impacted aircraft frames. The HEWABI from a typical ground service scenario has been previously tested and the desired type of damages have been generated, so that the aircraft panels could become representative study cases. The need of the aircraft industry for a rapid, ramp-friendly system to detect such WAID is here approached with guided ultrasonic waves (GUW) and a scanning tool that accesses the whole structure from the exterior side only. The wide coverage of the specimen provided by GUW has been coupled to a differential detection approach and is aided by an outlier statistical analysis to be able to inspect and detect faults in the challenging composite material and complex structure. The results will be presented and discussed with respect to the detection capability of the system and its response to the different damage types. Receiving Operating Characteristics curves (ROC) are also produced to quantify and assess the performance of the proposed method. Ongoing work is currently aimed at the penetration of the inner components of the structure, such as shear ties and C-frames, exploiting different frequency ranges and signal processing techniques. From the hardware and tool development side, different transducers and coupling methods, such as air-coupled transducers, are under investigation together with the design of a more suitable scanning technique.

Annual International Conference on Aging Aircraft (2nd) Held in Baltimore, Maryland on 3-5 October 1989

Science.gov (United States)

1990-02-01

Industrial Inspection Colin G. Drury , Ph.D., The Center for Industrial Effectiveness, State U niversity of N ew York, Buffalo...671 (.0172) TOTAL 780 (.0200) 38,220 (.9800) 39,000 (1.0) Figure 7 212 Industrial Inspection COLIN G. DRURY , PH.D. The Center for Industrial...could well be procedural as However, if the item is in fact faulty, then to when you are searching lower rivets with an 214 Colin G. Drury NDI device to

Time to retire : Indicators for aircraft fleets

NARCIS (Netherlands)

Newcamp, Jeffrey; Verhagen, W.J.C.; Curran, R.

2017-01-01

It is well known that aircraft fleets are aging alongside rising operations and support costs. Logisticians and fleet managers who better understand the milestones and timeline of an aging fleet can recognise potential savings. This paper outlines generalised milestones germane to military aircraft

The Ages and Stages Questionnaire and Neurodevelopmental Impairment in Two-Year-Old Preterm-Born Children

NARCIS (Netherlands)

Kerstjens, Jorien M.; Nijhuis, Ard; Hulzebos, Christian V.; van Imhoff, Deirdre E.; van Wassenaer-Leemhuis, Aleid G.; van Haastert, Ingrid C.; Lopriore, Enrico; Katgert, Titia; Swarte, Renate M.; van Lingen, Richard A.; Mulder, Twan L.; Laarman, Celeste R.; Steiner, Katerina; Dijk, Peter H.

2015-01-01

Objective To test the ability of the Ages and Stages Questionnaire, Third Edition (ASQ3) to help identify or exclude neurodevelopmental impairment (NDI) in very preterm-born children at the corrected age of two. Methods We studied the test results of 224 children, born at <32 postmenstrual weeks,

The Ages and Stages Questionnaire and Neurodevelopmental Impairment in Two-Year-Old Preterm-Born Children

NARCIS (Netherlands)

Kerstjens, Jorien M.; Nijhuis, Ard; Hulzebos, Christian V.; van Imhoff, Deirdre E.; van Wassenaer-Leemhuis, Aleid G.; van Haastert, Ingrid C.; Lopriore, Enrico; Katgert, Titia; Swarte, Renate M.; van Lingen, Richard A.; Mulder, Twan L.; Laarman, Céleste R.; Steiner, Katerina; Dijk, Peter H.

2015-01-01

To test the ability of the Ages and Stages Questionnaire, Third Edition (ASQ3) to help identify or exclude neurodevelopmental impairment (NDI) in very preterm-born children at the corrected age of two. We studied the test results of 224 children, born at <32 postmenstrual weeks, who had scores on

Fleet Management Decision Making With Individual Aircraft Tracking Data

NARCIS (Netherlands)

Newcamp, Jeffrey; Verhagen, W.J.C.; Curran, R.

2017-01-01

Individual aircraft tracking data can be used by aircraft fleet managers to detect patterns in historical usage as a means to aid aging aircraft decision-making. This work tackles two aspects of applying these tracking data: investigating retirement patterns and assessing how base assignment can

Secondary aerosol formation from photochemical aging of aircraft exhaust in a smog chamber

Directory of Open Access Journals (Sweden)

M. A. Miracolo

2011-05-01

Full Text Available Field experiments were performed to investigate the effects of photo-oxidation on fine particle emissions from an in-use CFM56-2B gas turbine engine mounted on a KC-135 Stratotanker airframe. Emissions were sampled into a portable smog chamber from a rake inlet installed one-meter downstream of the engine exit plane of a parked and chocked aircraft. The chamber was then exposed to sunlight and/or UV lights to initiate photo-oxidation. Separate tests were performed at different engine loads (4, 7, 30, 85 %. Photo-oxidation created substantial secondary particulate matter (PM, greatly exceeding the direct PM emissions at each engine load after an hour or less of aging at typical summertime conditions. After several hours of photo-oxidation, the ratio of secondary-to-primary PM mass was on average 35 ± 4.1, 17 ± 2.5, 60 ± 2.2, and 2.7 ± 1.1 for the 4, 7, 30, and 85 % load experiments, respectively. The composition of secondary PM formed strongly depended on load. At 4 % load, secondary PM was dominated by secondary organic aerosol (SOA. At higher loads, the secondary PM was mainly secondary sulfate. A traditional SOA model that accounts for SOA formation from single-ring aromatics and other volatile organic compounds underpredicts the measured SOA formation by ~60 % at 4 % load and ~40 % at 85 % load. Large amounts of lower-volatiliy organic vapors were measured in the exhaust; they represent a significant pool of SOA precursors that are not included in traditional SOA models. These results underscore the importance of accounting for atmospheric processing when assessing the influence of aircraft emissions on ambient PM levels. Models that do not account for this processing will likely underpredict the contribution of aircraft emissions to local and regional air pollution.

Two-year neurodevelopmental outcomes of extremely preterm infants treated with early hydrocortisone: treatment effect according to gestational age at birth.

Science.gov (United States)

Baud, Olivier; Trousson, Clémence; Biran, Valérie; Leroy, Emilie; Mohamed, Damir; Alberti, Corinne

2018-01-10

To determine whether early hydrocortisone treatment in extremely preterm infants affects neurodevelopmental outcomes at 2 years of age according to gestational age at birth. This is an exploratory analysis of neurodevelopmental outcomes by gestational age strata from the PREMILOC trial, in which patients were randomly assigned to receive either placebo or low-dose hydrocortisone and randomisation was stratified by gestational age groups (24-25 and 26-27 weeks of gestation). Neurodevelopmental impairment (NDI) was assessed using a standardised neurological examination and the revised Brunet-Lézine scale at 22 months of corrected age. A total of 379 of 406 survivors were evaluated, 96/98 in the gestational age group of 24-25 weeks and 283/308 in the gestational age group of 26-27 weeks. Among surviving infants born at 24-25 weeks, significant improvement in global neurological assessment was observed in the hydrocortisone group compared with the placebo group (P=0.02) with a risk of moderate-to-severe NDI of 2% and 18%, respectively (risk difference 16 (95% CI -28% to -5%)). In contrast, no statistically significant difference between treatment groups was observed in infants born at 26-27 weeks (P=0.95) with a similar risk of moderate-to-severe NDI of 9% in both groups. The incidence of cerebral palsy or other major neurological impairments were found similar between treatment groups in each gestational group. In an exploratory analysis of neurodevelopmental outcomes from the PREMILOC trial, early low-dose hydrocortisone was associated with a statistically significant improvement in neurodevelopmental outcomes in infants born at 24 and 25 weeks of gestation. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2018. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

Recent and Future Enhancements in NDI for Aircraft Structures

Science.gov (United States)

2015-11-30

manufacture, use, or sell any patented invention that may relate to them. Qualified requestors may obtain copies of this report from the Defense...and was also used to establish the safe-life of earlier designs that were subjected to a fatigue test. Losses of an F-111 in December 1969 and an F-5...Accidents / Incidents, March 2010. [2] Lincoln, J.W., “Damage Tolerance – USAF Experience,” Proceedings of the 13th Symposium of the International

Metabolic Syndrome and Cardio-Cerebrovascular Risk Disparities Between Pilots and Aircraft Mechanics.

Science.gov (United States)

Kim, Myeong-Bo; Kim, Hyun-Jin; Kim, Soo-Hyeon; Lee, Suk-Ho; Lee, Se-Ho; Park, Won-Ju

2017-09-01

In the Republic of Korea Air Force, the health of pilots is strictly supervised, but there is comparatively not enough interest in aircraft mechanics' health. Among mechanics, who are heavily involved in military aircraft maintenance, the occurrence of sudden cardio-cerebrovascular diseases (CCVDs) is a possible risk factor during the maintenance process, which should be performed perfectly. We performed health examinations on 2123 male aircraft pilots and 1271 aircraft mechanics over 30 yr of age and determined the prevalence of metabolic syndrome (MetS), an important risk factor for CCVDs. The prevalence of MetS in the aircraft mechanics (21.3%) was significantly higher than in the pilots (12.6%), and the gap in prevalence tended to grow as age increased. Among aircraft mechanics in their 30s and 40s, the prevalence of MetS was lower than in the general population. However, the prevalence of MetS among aircraft mechanics in their 50s (36.0%) was similar to that in the general population (35.7%). Systematic health management is needed for aircraft mechanics for aviation safety and for the maintenance of military strength via the prevention of CCVDs.Kim M-B, Kim H-J, Kim S-H, Lee S-H, Lee S-H, Park W-J. Metabolic syndrome and cardio-cerebrovascular risk disparities between pilots and aircraft mechanics. Aerosp Med Hum Perform. 2017; 88(9):866-870.

Transition to high rate aerospace NDI processes

Science.gov (United States)

Vanderheiden, Bert; Thomson, Clint; Ivakhnenko, Igor; Garner, Chuck

2018-04-01

With the rapidly expanding use of carbon fiber composite materials in military and commercial aircraft, processes to manufacture and inspect the structural components must evolve to ensure economic viability. Inspection techniques which were developed to inspect products produced at a rate of one or two structures a month are not fast or flexible enough to inspect more than 8500 parts per month. This presentation describes the evolution of phased array ultrasonic inspection systems to provide the increased rate capacity, the flexibility to accommodate multiple unique designs, and the ability to rapidly adjust to product design changes. The paper will describe how system developments were made in response to new programs resulting in a much less expensive, higher degree of accuracy, increased flexibility, and lower cycle time inspections.

Advances in Protective Coatings and Their Application to Ageing Aircraft

Science.gov (United States)

2000-04-01

Aerospace Material Specification Selectively (1997) Strippable Acrylic Finishing Schemes - Matt and Glossy - 23. K.R. Baldwin and C.J.E. Smith, Repair...corrosion through design, the selection of military and civil aircraft during the last thirty years. Research materials that are resistant to corrosion and...compliant coatings. initiation of corrosion. This paper first examines the general principles involved in 2.2 Materials selection the corrosion

Recent and Future Enhancements in NDI for Aircraft Structures (Postprint)

Science.gov (United States)

2015-11-30

manufacture, use, or sell any patented invention that may relate to them. Qualified requestors may obtain copies of this report from the Defense...and was also used to establish the safe-life of earlier designs that were subjected to a fatigue test. Losses of an F-111 in December 1969 and an F-5...Accidents / Incidents, March 2010. [2] Lincoln, J.W., “Damage Tolerance – USAF Experience,” Proceedings of the 13th Symposium of the International

RECENT AND FUTURE ENHANCEMENTS IN NDI FOR AIRCRAFT STRUCTURES POSTPRINT

Science.gov (United States)

2015-09-10

manufacture, use, or sell any patented invention that may relate to them. Qualified requestors may obtain copies of this report from the Defense...and was also used to establish the safe-life of earlier designs that were subjected to a fatigue test. Losses of an F-111 in December 1969 and an F-5...Accidents / Incidents, March 2010. [2] Lincoln, J.W., “Damage Tolerance – USAF Experience,” Proceedings of the 13th Symposium of the International

Database on aircraft accidents

International Nuclear Information System (INIS)

Nishio, Masahide; Koriyama, Tamio

2012-09-01

The Reactor Safety Subcommittee in the Nuclear Safety and Preservation Committee published the report 'The criteria on assessment of probability of aircraft crash into light water reactor facilities' as the standard method for evaluating probability of aircraft crash into nuclear reactor facilities in July 2002. In response to the report, Japan Nuclear Energy Safety Organization has been collecting open information on aircraft accidents of commercial airplanes, self-defense force (SDF) airplanes and US force airplanes every year since 2003, sorting out them and developing the database of aircraft accidents for latest 20 years to evaluate probability of aircraft crash into nuclear reactor facilities. This year, the database was revised by adding aircraft accidents in 2010 to the existing database and deleting aircraft accidents in 1991 from it, resulting in development of the revised 2011 database for latest 20 years from 1991 to 2010. Furthermore, the flight information on commercial aircrafts was also collected to develop the flight database for latest 20 years from 1991 to 2010 to evaluate probability of aircraft crash into reactor facilities. The method for developing the database of aircraft accidents to evaluate probability of aircraft crash into reactor facilities is based on the report 'The criteria on assessment of probability of aircraft crash into light water reactor facilities' described above. The 2011 revised database for latest 20 years from 1991 to 2010 shows the followings. The trend of the 2011 database changes little as compared to the last year's one. (1) The data of commercial aircraft accidents is based on 'Aircraft accident investigation reports of Japan transport safety board' of Ministry of Land, Infrastructure, Transport and Tourism. 4 large fixed-wing aircraft accidents, 58 small fixed-wing aircraft accidents, 5 large bladed aircraft accidents and 114 small bladed aircraft accidents occurred. The relevant accidents for evaluating

14 CFR 21.6 - Manufacture of new aircraft, aircraft engines, and propellers.

Science.gov (United States)

2010-01-01

... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Manufacture of new aircraft, aircraft... Manufacture of new aircraft, aircraft engines, and propellers. (a) Except as specified in paragraphs (b) and (c) of this section, no person may manufacture a new aircraft, aircraft engine, or propeller based on...

Database on aircraft accidents

International Nuclear Information System (INIS)

Nishio, Masahide; Koriyama, Tamio

2013-11-01

The Reactor Safety Subcommittee in the Nuclear Safety and Preservation Committee published 'The criteria on assessment of probability of aircraft crash into light water reactor facilities' as the standard method for evaluating probability of aircraft crash into nuclear reactor facilities in July 2002. In response to this issue, Japan Nuclear Energy Safety Organization has been collecting open information on aircraft accidents of commercial airplanes, self-defense force (SDF) airplanes and US force airplanes every year since 2003, sorting out them and developing the database of aircraft accidents for the latest 20 years to evaluate probability of aircraft crash into nuclear reactor facilities. In this report the database was revised by adding aircraft accidents in 2011 to the existing database and deleting aircraft accidents in 1991 from it, resulting in development of the revised 2012 database for the latest 20 years from 1992 to 2011. Furthermore, the flight information on commercial aircrafts was also collected to develop the flight database for the latest 20 years from 1992 to 2011 to evaluate probability of aircraft crash into reactor facilities. The method for developing the database of aircraft accidents to evaluate probability of aircraft crash into reactor facilities is based on the report 'The criteria on assessment of probability of aircraft crash into light water reactor facilities' described above. The 2012 revised database for the latest 20 years from 1992 to 2011 shows the followings. The trend of the 2012 database changes little as compared to the last year's report. (1) The data of commercial aircraft accidents is based on 'Aircraft accident investigation reports of Japan transport safety board' of Ministry of Land, Infrastructure, Transport and Tourism. The number of commercial aircraft accidents is 4 for large fixed-wing aircraft, 58 for small fixed-wing aircraft, 5 for large bladed aircraft and 99 for small bladed aircraft. The relevant accidents

Hearing status among aircraft maintenance personnel in a commercial airline company

Directory of Open Access Journals (Sweden)

Greta Smedje

2011-01-01

Full Text Available The aim was to study subjective and objective hearing loss in a population of aircraft maintenance workers and identify predictors. A total of 327 aircraft maintenance personnel answered a self-administered work environment questionnaire (response rate 76% and underwent audiometric test. The mean values for the hearing threshold at 3, 4, and 6 kHz for the ear with the most hearing loss were compared with a Swedish population database of persons not occupationally exposed to noise. Equivalent noise exposure during a working day was measured. Relationships between subjective and objective hearing loss and possible predictors (age, years of employment, self-reported exposure to solvents, blood pressure, and psycho-social factors were analyzed by multiple logistic regression. At younger ages (<40 years, aircraft maintenance workers had higher hearing thresholds (1-3 dB compared to the reference group, but such a difference was not found in older employees. Relationships were found between age and objective hearing loss, and between exposure to solvents and reported subjective hearing loss. Equivalent noise exposure during working days were 70-91 dB(A with a maximal noise level of 119 dB(A. Aircraft maintenance workers are exposed to equivalent noise levels above the Swedish occupational standard, including some very high peak exposures. Younger employees have a higher age-matched hearing threshold level compared with a reference group. Thus, there is a need for further preventive measures.

Hull loss accident model for narrow body commercial aircraft

Directory of Open Access Journals (Sweden)

Somchanok Tiabtiamrat

2010-10-01

Full Text Available Accidents with narrow body aircraft were statistically evaluated covering six families of commercial aircraft includingBoeing B737, Airbus A320, McDonnell Douglas MD80, Tupolev TU134/TU154 and Antonov AN124. A risk indicator for eachflight phase was developed based on motion characteristics, duration time, and the presence of adverse weather conditions.The estimated risk levels based on these risk indicators then developed from the risk indicator. Regression analysis indicatedvery good agreement between the estimated risk level and the accident ratio of hull loss cases per number of delivered aircraft.The effect of time on the hull loss accident ratio per delivered aircraft was assessed for B737, A320 and MD80. Equationsrepresenting the effect of time on hull loss accident ratio per delivered aircraft were proposed for B737, A320, and MD80,while average values of hull loss accident ratio per delivered aircraft were found for TU134, TU154, and AN 124. Accidentprobability equations were then developed for each family of aircraft that the probability of an aircraft in a hull loss accidentcould be estimated for any aircraft family, flight phase, presence of adverse weather factor, hour of day, day of week, monthof year, pilot age, and pilot flight hour experience. A simplified relationship between estimated hull loss accident probabilityand unsafe acts by human was proposed. Numerical investigation of the relationship between unsafe acts by human andfatality ratio suggested that the fatality ratio in hull loss accident was dominated primarily by the flight phase media.

Advanced aircraft service life monitoring method via flight-by-flight load spectra

Science.gov (United States)

Lee, Hongchul

This research is an effort to understand current method and to propose an advanced method for Damage Tolerance Analysis (DTA) for the purpose of monitoring the aircraft service life. As one of tasks in the DTA, the current indirect Individual Aircraft Tracking (IAT) method for the F-16C/D Block 32 does not properly represent changes in flight usage severity affecting structural fatigue life. Therefore, an advanced aircraft service life monitoring method based on flight-by-flight load spectra is proposed and recommended for IAT program to track consumed fatigue life as an alternative to the current method which is based on the crack severity index (CSI) value. Damage Tolerance is one of aircraft design philosophies to ensure that aging aircrafts satisfy structural reliability in terms of fatigue failures throughout their service periods. IAT program, one of the most important tasks of DTA, is able to track potential structural crack growth at critical areas in the major airframe structural components of individual aircraft. The F-16C/D aircraft is equipped with a flight data recorder to monitor flight usage and provide the data to support structural load analysis. However, limited memory of flight data recorder allows user to monitor individual aircraft fatigue usage in terms of only the vertical inertia (NzW) data for calculating Crack Severity Index (CSI) value which defines the relative maneuver severity. Current IAT method for the F-16C/D Block 32 based on CSI value calculated from NzW is shown to be not accurate enough to monitor individual aircraft fatigue usage due to several problems. The proposed advanced aircraft service life monitoring method based on flight-by-flight load spectra is recommended as an improved method for the F-16C/D Block 32 aircraft. Flight-by-flight load spectra was generated from downloaded Crash Survival Flight Data Recorder (CSFDR) data by calculating loads for each time hack in selected flight data utilizing loads equations. From

A service life extension (SLEP) approach to operating aging aircraft beyond their original design lives

Science.gov (United States)

Pentz, Alan Carter

With today's uncertain funding climate (including sequestration and continuing budget resolutions), decision makers face severe budgetary challenges to maintain dominance through all aspects of the Department of Defense (DoD). To meet war-fighting capabilities, the DoD continues to extend aircraft programs beyond their design service lives by up to ten years, and occasionally much more. The budget requires a new approach to traditional extension strategies (i.e., reuse, reset, and reclamation) for structural hardware. While extending service life without careful controls can present a safety concern, future operations planning does not consider how much risk is present when operating within sound structural principles. Traditional structural hardware extension methods drive increased costs. Decision makers often overlook the inherent damage tolerance and fatigue capability of structural components and rely on simple time- and flight-based cycle accumulation when determining aircraft retirement lives. This study demonstrates that decision makers should consider risk in addition to the current extension strategies. Through an evaluation of eight military aircraft programs and the application and simulation of F-18 turbine engine usage data, this dissertation shows that insight into actual aircraft mission data, consideration of fatigue capability, and service extension length are key factors to consider. Aircraft structural components, as well as many critical safety components and system designs, have a predefined level of conservatism and inherent damage tolerance. The methods applied in this study would apply to extensions of other critical structures such as bridges. Understanding how much damage tolerance is built into the design compared to the original design usage requirements presents the opportunity to manage systems based on risk. The study presents the sensitivity of these factors and recommends avenues for further research.

Creep-age forming of AA7475 aluminum panels for aircraft lower wing skin application

Directory of Open Access Journals (Sweden)

Diego José Inforzato

2012-08-01

Full Text Available Creep-age forming (CAF is an interesting process for the airframe industry, as it is able to form or shape panels into smooth, but complex, curvatures. In the CAF process, the ageing cycle of the alloy is used to relax external loads imposed to the part, through creep mechanisms. Those relaxed stresses impose a new curvature to the part. At the end of the process, significant spring back (sometimes about 70% is observed and the success in achieving the desired form depends on how the spring back can be predicted in order to compensate it by tooling changes. Most of the applications relate to simple (non stiffened panels. The present work deals with the CAF of aluminum panels for aircraft wing skin application. CAF was performed using vacuum-bagging autoclave technique in small scale complex shape stiffened panels, machined from an AA7475 alloy plate. An analytical reference model from the literature was employed estimate the spring back effect in such panel geometry. This model that deals with simple plates was adapted to stiffened panels using a geometric simplification, resulting in a semi-empirical model. The results demonstrate that CAF is a promising process to form stiffened panels, and the spring back can be roughly estimated through a simple model and few experiments.

Aircraft Impact Assessment of APR1400 Reactor Containment Building

International Nuclear Information System (INIS)

Moon, Il Hwan; Kim, Do Yeon; Kim, Jae Hee; Kim, Sang Yun

2011-01-01

The implementation of a protection to withstand aircraft impact on safety-related structures and systems is basically based on a probabilistic evaluation for each site, if the licensing body doesn't require a deterministic approach. Existing nuclear power plants in Korea were designed based on the probabilistic approach, and the aircraft impact hazard remained less than a probability of 10 -7 . However, a man-made aircraft impact have been considered as a possible external accident for the nuclear power plant. New plant designs that are to be constructed in the U.S. after July 2009 must consider the effect of impact from a large commercial aircraft according to the requirements of 10 CFR 50.150. Especially, Reactor Containment Building (RCB) housing the safety-related equipment and fuels should be protected safely against aircraft crash without perforation and scabbing failure of external wall. APR1400 RCB is constructed as a prestressed concrete containment vessel (PCCV) which is surrounded by the auxiliary building housing additional safety-related equipment and other systems. In this study, the aircraft impact analyses for the RCB are carried out using Riera forcing function and aircraft model. Considered external wall thickness is 4 ft 6 in. for the cylindrical wall and 4 ft for the dome. Actual strengths of concrete and steel are considered as the material properties. For these analyses, the dynamic increment factor and concrete aging effect are considered in accordance with NEI 07-13(2011)

Propulsion controlled aircraft computer

Science.gov (United States)

Cogan, Bruce R. (Inventor)

2010-01-01

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

Small transport aircraft technology

Science.gov (United States)

Williams, L. J.

1983-01-01

Information on commuter airline trends and aircraft developments is provided to upgrade the preliminary findings of a NASA-formed small transport aircraft technology (STAT) team, established to determine whether the agency's research and development programs could help commuter aircraft manufacturers solve technical problems related to passenger acceptance and use of 19- to 50-passenger aircraft. The results and conclusions of the full set of completed STAT studies are presented. These studies were performed by five airplane manufacturers, five engine manufacturers, and two propeller manufacturers. Those portions of NASA's overall aeronautics research and development programs which are applicable to commuter aircraft design are summarized. Areas of technology that might beneficially be expanded or initiated to aid the US commuter aircraft manufacturers in the evolution of improved aircraft for the market are suggested.

THE PROBLEMS OF PERFORMANCE MONITORING TO TAKLE THE TASKS OF THE AIRCRAFT CONTINUED AIRWORTHINESS

Directory of Open Access Journals (Sweden)

Yu. M. Chinyuchin

2017-01-01

Full Text Available Improving of the aircraft continued airworthiness system is currently becoming of particular importance applied both to aircraft of domestic and foreign production, used in civil aviation of Russia. This article discusses the background and content of the tasks for long-haul aircraft continued airworthiness, which presents a challenge directly related to the provision of intensive, regular, economically viable, and safe operation of assigned airline fleet. A special place among the problems of continued airworthiness is held by the creation and organization of mechanisms and methods of resource status and age of the assigned airline fleet monitoring to manage its forecasting and timely updates. Not least important among the issues of resource and age structure monitoring to be considered is the need to improve the design of aircraft, taking into account preliminary technical and economic feasibility assessment of its modifications in the interests of the operator. A deep study of the contents of the monitoring allows to develop up-to-date methodological and scientific basis for building an integrated system of aircraft resource management and timing services. This system is developed based on the integrated approach that allows to provide a solution to the entire set of problems presented in this article and faced by professionals and scientists involved in the aircraft maintenance programs development on the stages of their design and manufacturing and long operation of aircraft continued airworthiness.

Impact of Age and Duration of Symptoms on Surgical Outcome of Single-Level Microscopic Anterior Cervical Discectomy and Fusion in the Patients with Cervical Spondylotic Radiculopathy.

Science.gov (United States)

Omidi-Kashani, Farzad; Ghayem Hasankhani, Ebrahim; Ghandehari, Reza

2014-01-01

We aim to evaluate the impact of age and duration of symptoms on surgical outcome of the patients with cervical spondylotic radiculopathy (CSR) who had been treated by single-level microscopic anterior cervical discectomy and fusion (ACDF). We retrospectively evaluated 68 patients (48 female and 20 male) with a mean age of 41.2 ± 4.3 (ranged from 24 to 72 years old) in our Orthopedic Department, Imam Reza Hospital. They were followed up for 31.25 ± 4.1 months (ranged from 25 to 65 months). Pain and disability were assessed by Visual Analogue Scale (VAS) and Neck Disability Index (NDI) questionnaires in preoperative and last follow-up visits. Functional outcome was eventually evaluated by Odom's criteria. Surgery could significantly improve pain and disability from preoperative 6.2 ± 1.4 and 22.2 ± 6.2 to 3.5 ± 2.0 and 8.7 ± 5.2 (1-21) at the last follow-up visit, respectively. Satisfactory outcomes were observed in 89.7%. Symptom duration of more and less than six months had no effect on surgical outcome, but the results showed a statistically significant difference in NDI improvement in favor of the patients aged more than 45 years (P = 0.032), although pain improvement was similar in the two groups.

Airsickness and aircraft motion during short-haul flights.

Science.gov (United States)

Turner, M; Griffin, M J; Holland, I

2000-12-01

There is little quantitative information that can be used to predict the incidence of airsickness from the motions experienced in military or civil aviation. This study examines the relationship between low-frequency aircraft motion and passenger sickness in short-haul turboprop flights within the United Kingdom. A questionnaire survey of 923 fare-paying passengers was conducted on 38 commercial airline flights. Concurrent measurements of aircraft motion were made on all journeys, yielding approximately 30 h of aircraft motion data. Overall, 0.5% of passengers reported vomiting, 8.4% reported nausea (range 0% to 34.8%) and 16.2% reported illness (range 0% to 47.8%) during flight. Positive correlations were found between the percentage of passengers who experienced nausea or felt ill and the magnitude of low-frequency lateral and vertical motion, although neither motion uniquely predicted airsickness. The incidence of motion sickness also varied with passenger age, gender, food consumption and activity during air travel. No differences in sickness were found between passengers located in different seating sections of the aircraft, or as a function of moderate levels of alcohol consumption. The passenger responses suggest that a useful prediction of airsickness can be obtained from magnitudes of low frequency aircraft motion. However, some variations in airsickness may also be explained by individual differences between passengers and their psychological perception of flying.

Predicting visibility of aircraft.

Directory of Open Access Journals (Sweden)

Andrew Watson

Full Text Available Visual detection of aircraft by human observers is an important element of aviation safety. To assess and ensure safety, it would be useful to be able to be able to predict the visibility, to a human observer, of an aircraft of specified size, shape, distance, and coloration. Examples include assuring safe separation among aircraft and between aircraft and unmanned vehicles, design of airport control towers, and efforts to enhance or suppress the visibility of military and rescue vehicles. We have recently developed a simple metric of pattern visibility, the Spatial Standard Observer (SSO. In this report we examine whether the SSO can predict visibility of simulated aircraft images. We constructed a set of aircraft images from three-dimensional computer graphic models, and measured the luminance contrast threshold for each image from three human observers. The data were well predicted by the SSO. Finally, we show how to use the SSO to predict visibility range for aircraft of arbitrary size, shape, distance, and coloration.

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

OpenAIRE

Seresinhe, R.

2014-01-01

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

Aircraft to aircraft intercomparison during SEMAPHORE

Science.gov (United States)

Lambert, Dominique; Durand, Pierre

1998-10-01

During the Structure des Echanges Mer-Atmosphère, Propriétés des Hétérogénéités Océaniques: Recherche Expérimentale (SEMAPHORE) experiment, performed in the Azores region in 1993, two French research aircraft were simultaneously used for in situ measurements in the atmospheric boundary layer. We present the results obtained from one intercomparison flight between the two aircraft. The mean parameters generally agree well, although the temperature has to be slightly shifted in order to be in agreement for the two aircraft. A detailed comparison of the turbulence parameters revealed no bias. The agreement is good for variances and is satisfactory for fluxes and skewness. A thorough study of the errors involved in flux computation revealed that the greatest accuracy is obtained for latent heat flux. Errors in sensible heat flux are considerably greater, and the worst results are obtained for momentum flux. The latter parameter, however, is more accurate than expected from previous parameterizations.

Back pain and its consequences among Polish Air Force pilots flying high performance aircraft

Directory of Open Access Journals (Sweden)

Aleksandra Truszczyńska

2014-04-01

Full Text Available Objectives: Back pain in Air Force fast jet pilots has been studied by several air forces and found to be relatively common. The objective of the study was to determine the prevalence and degree of the pain intensity in the cervical, thoracic and lumbar spine, subjective risk factors and their effect on the pilots' performance while flying high maneuver aircrafts and the consequences for cognitive deficiencies. Material and Methods: The study was designed as a retrospective, anonymous questionnaire survey, collecting data on the age, aircraft type, flying hours, pain characteristics, physical activity, etc. The study was participated by 94 pilots aged 28-45 years (mean age: 35.9±3.3 years, actively flying fast jet aircrafts Su-22, Mig-29 and F-16. The estimates regarding the level of the subjective back pain were established using visual analogue scales (VAS. Results: The values of the Cochran and Cox T-test for heterogeneous variances are as follows: for the total number of flying hours: F = 2.53, p = 0.0145, for the pilot's age: F = 3.15, p = 0.003, and for the BMI factor F = 2.73, p = 0.008. Conclusions: Our questionnaire survey showed a significant problem regarding spinal conditions in high performance aircraft pilots. The determination of the risk factors may lead to solving this problem and help eliminate the effect of the unfavorable environment on piloting jet aircrafts. Experiencing back pain during the flight might influence the mission performance and flight safety. The costs of pilots education are enormous and inability to fly, or even disability, leads to considerable economic loss. More research on specific prevention strategies is warranted in order to improve the in-flight working environment of fighter pilots.

Success Stories in Control: Nonlinear Dynamic Inversion Control

Science.gov (United States)

Bosworth, John T.

2010-01-01

NASA plays an important role in advancing the state of the art in flight control systems. In the case of Nonlinear Dynamic Inversion (NDI) NASA supported initial implementation of the theory in an aircraft and demonstration in a space vehicle. Dr. Dale Enns of Honeywell Aerospace Advanced Technology performed this work in cooperation with NASA and under NASA contract. Honeywell and Lockheed Martin were subsequently contracted by AFRL to create "Design Guidelines for Multivariable Control Theory". This foundational work directly contributed to the advancement of the technology and the credibility of the control law as a design option. As a result Honeywell collaborated with Lockheed Martin to produce a Nonlinear Dynamic Inversion controller for the X-35 and subsequently Lockheed Martin did the same for the production Lockheed Martin F-35 vehicle. The theory behind NDI is to use a systematic generalized approach to controlling a vehicle. Using general aircraft nonlinear equations of motion and onboard aerodynamic, mass properties, and engine models specific to the vehicle, a relationship between control effectors and desired aircraft motion can be formulated. Using this formulation a control combination is used that provides a predictable response to commanded motion. Control loops around this formulation shape the response as desired and provide robustness to modeling errors. Once the control law is designed it can be used on a similar class of vehicle with only an update to the vehicle specific onboard models.

Impact of Age and Duration of Symptoms on Surgical Outcome of Single-Level Microscopic Anterior Cervical Discectomy and Fusion in the Patients with Cervical Spondylotic Radiculopathy

Directory of Open Access Journals (Sweden)

Farzad Omidi-Kashani

2014-01-01

Full Text Available We aim to evaluate the impact of age and duration of symptoms on surgical outcome of the patients with cervical spondylotic radiculopathy (CSR who had been treated by single-level microscopic anterior cervical discectomy and fusion (ACDF. We retrospectively evaluated 68 patients (48 female and 20 male with a mean age of 41.2±4.3 (ranged from 24 to 72 years old in our Orthopedic Department, Imam Reza Hospital. They were followed up for 31.25±4.1 months (ranged from 25 to 65 months. Pain and disability were assessed by Visual Analogue Scale (VAS and Neck Disability Index (NDI questionnaires in preoperative and last follow-up visits. Functional outcome was eventually evaluated by Odom’s criteria. Surgery could significantly improve pain and disability from preoperative 6.2±1.4 and 22.2±6.2 to 3.5±2.0 and 8.7±5.2 (1–21 at the last follow-up visit, respectively. Satisfactory outcomes were observed in 89.7%. Symptom duration of more and less than six months had no effect on surgical outcome, but the results showed a statistically significant difference in NDI improvement in favor of the patients aged more than 45 years (P=0.032, although pain improvement was similar in the two groups.

COMPARATIVE ANALYSIS OF TRANSPORT AIRCRAFT, BACKROUND FOR SHORT/ MEDIUM COURIER TRANSPORT AIRCRAFT PROCUREMENT

Directory of Open Access Journals (Sweden)

Matei POPA

2010-03-01

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.

SOLAR AIRCRAFT DESIGN

OpenAIRE

RAHMATI, Sadegh; GHASED, Amir

2015-01-01

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

Aircraft operations management manual

Science.gov (United States)

1992-01-01

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

Conceptual design of high speed supersonic aircraft: A brief review on SR-71 (Blackbird) aircraft

Science.gov (United States)

Xue, Hui; Khawaja, H.; Moatamedi, M.

2014-12-01

The paper presents the conceptual design of high-speed supersonic aircraft. The study focuses on SR-71 (Blackbird) aircraft. The input to the conceptual design is a mission profile. Mission profile is a flight profile of the aircraft defined by the customer. This paper gives the SR-71 aircraft mission profile specified by US air force. Mission profile helps in defining the attributes the aircraft such as wing profile, vertical tail configuration, propulsion system, etc. Wing profile and vertical tail configurations have direct impact on lift, drag, stability, performance and maneuverability of the aircraft. A propulsion system directly influences the performance of the aircraft. By combining the wing profile and the propulsion system, two important parameters, known as wing loading and thrust to weight ratio can be calculated. In this work, conceptual design procedure given by D. P. Raymer (AIAA Educational Series) is applied to calculate wing loading and thrust to weight ratio. The calculated values are compared against the actual values of the SR-71 aircraft. Results indicates that the values are in agreement with the trend of developments in aviation.

Solar thermal aircraft

Science.gov (United States)

Bennett, Charles L.

2007-09-18

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

Clinical outcome of narrow diameter implants inserted into allografts

Directory of Open Access Journals (Sweden)

Maurizio Franco

2009-08-01

Full Text Available OBJECTIVE: Narrow diameter implants (NDI (i.e. diameter <3.75 mm are a potential solution for specific clinical situations, such as reduced interradicular bone, thin alveolar crest and replacement of teeth with small cervical diameter. NDI have been available in clinical practice since the 1990s, but only few studies have analyzed their clinical outcome and no study have investigated NDI inserted in fresh-frozen bone (FFB grafts. Thus, a retrospective study on a series of NDI placed in homologue FFB was designed to evaluate their clinical outcome. MATERIAL AND METHODS: In the period between December 2003 and December 2006, 36 patients (22 females and 14 males, mean age 53 years with FFB grafts were selected and 94 different NDI were inserted. The mean follow-up was 25 months. To evaluate the effect of several host-, surgery-, and implant-related factors, marginal bone loss (MBL was considered an indicator of success rate (SCR. The Kaplan Meier algorithm and Cox regression were used. RESULTS: Only 5 out of 94 implants were lost (i.e. survival rate - SVR 95.7% and no differences were detected among the studied variables. On the contrary, the Cox regression showed that the graft site (i.e. maxilla reduced MBL. CONCLUSIONS: NDI inserted in FFB have a high SVR and SCR similar to those reported in previous studies on regular and NDI inserted in non-grafted jaws. Homologue FFB is a valuable material in the insertion of NDI.

Long Range Aircraft Trajectory Prediction

OpenAIRE

Magister, Tone

2009-01-01

The subject of the paper is the improvement of the aircraft future trajectory prediction accuracy for long-range airborne separation assurance. The strategic planning of safe aircraft flights and effective conflict avoidance tactics demand timely and accurate conflict detection based upon future four–dimensional airborne traffic situation prediction which is as accurate as each aircraft flight trajectory prediction. The improved kinematics model of aircraft relative flight considering flight ...

Fatigue and Fracture Characterization of Aircraft Aluminum Alloys Damaged by Prior Corrosion

National Research Council Canada - National Science Library

Baldwin, J

2002-01-01

At the time of the initiation of this project, there was no comprehensive data describing corrosion's effect on the fatigue and fracture behavior of aluminum alloys typically found in aging aircraft...

Adapting existing training standards for unmanned aircraft: finding ways to train staff for unmanned aircraft operations

CSIR Research Space (South Africa)

Burger, CR

2011-09-01

Full Text Available - unmanned aircraft; pilot training. I. INTRODUCTION Unmanned aircraft offer flexibility not found in manned aircraft. They can be made smaller and cheaper to operate. They offer payload advantages relative to small manned aircraft. They can also perform... certificate to non-state users. To facilitate useful operations by UAs, future operations must be subject to no more than routine notification (e.g. an ATC flight plan), just like manned aircraft already are. Before such operations can be established, some...

40 CFR 87.6 - Aircraft safety.

Science.gov (United States)

2010-07-01

... 40 Protection of Environment 20 2010-07-01 2010-07-01 false Aircraft safety. 87.6 Section 87.6... POLLUTION FROM AIRCRAFT AND AIRCRAFT ENGINES General Provisions § 87.6 Aircraft safety. The provisions of... met within the specified time without creating a safety hazard. ...

Structural Load Alleviation Applied to Next Generation Aircraft and Wind Turbines

Science.gov (United States)

Frost, Susan

2011-01-01

Reducing the environmental impact of aviation is a goal of the Subsonic Fixed Wing Project under the Fundamental Aeronautics Program of NASAs Aeronautics Research Mission Directorate. Environmental impact of aviation is being addressed by novel aircraft configurations and materials that reduce aircraft weight and increase aerodynamic efficiency. NASA is developing tools to address the challenges of increased airframe flexibility created by wings constructed with reduced structural material and novel light-weight materials. This talk will present a framework and demonstration of a flight control system using optimal control allocation with structural load feedback and constraints to achieve safe aircraft operation. As wind turbines age, they become susceptible to many forms of blade degradation. Results will be presented on work in progress that uses adaptive contingency control for load mitigation in a wind turbine simulation with blade damage progression modeled.

Comparison of Expert Adjudicated Coronary Heart Disease and Cardiovascular Disease Mortality With the National Death Index: Results From the REasons for Geographic And Racial Differences in Stroke (REGARDS) Study.

Science.gov (United States)

Olubowale, Olusola Tope; Safford, Monika M; Brown, Todd M; Durant, Raegan W; Howard, Virginia J; Gamboa, Christopher; Glasser, Stephen P; Rhodes, J David; Levitan, Emily B

2017-05-03

The National Death Index (NDI) is widely used to detect coronary heart disease (CHD) and cardiovascular disease (CVD) deaths, but its reliability has not been examined recently. We compared CHD and CVD deaths detected by NDI with expert adjudication of 4010 deaths that occurred between 2003 and 2013 among participants in the REGARDS (REasons for Geographic And Racial Differences in Stroke) cohort of black and white adults in the United States. NDI derived CHD mortality had sensitivity 53.6%, specificity 90.3%, positive predictive value 54.2%, and negative predictive value 90.1%. NDI-derived CVD mortality had sensitivity 73.4%, specificity 84.5%, positive predictive value 70.6%, and negative predictive value 86.2%. Among NDI-derived CHD and CVD deaths, older age (odds ratios, 1.06 and 1.04 per 1-year increase) was associated with a higher probability of disagreement with the adjudicated cause of death, whereas among REGARDS adjudicated CHD and CVD deaths a history of CHD or CVD was associated with a lower probability of disagreement with the NDI-derived causes of death (odds ratios, 0.59 and 0.67, respectively). The modest accuracy and differential performance of NDI-derived cause of death may impact CHD and CVD mortality statistics. © 2017 The Authors. Published on behalf of the American Heart Association, Inc., by Wiley.

Examining the Relationship Between Passenger Airline Aircraft Maintenance Outsourcing and Aircraft Safety

Science.gov (United States)

Monaghan, Kari L.

The problem addressed was the concern for aircraft safety rates as they relate to the rate of maintenance outsourcing. Data gathered from 14 passenger airlines: AirTran, Alaska, America West, American, Continental, Delta, Frontier, Hawaiian, JetBlue, Midwest, Northwest, Southwest, United, and USAir covered the years 1996 through 2008. A quantitative correlational design, utilizing Pearson's correlation coefficient, and the coefficient of determination were used in the present study to measure the correlation between variables. Elements of passenger airline aircraft maintenance outsourcing and aircraft accidents, incidents, and pilot deviations within domestic passenger airline operations were analyzed, examined, and evaluated. Rates of maintenance outsourcing were analyzed to determine the association with accident, incident, and pilot deviation rates. Maintenance outsourcing rates used in the evaluation were the yearly dollar expenditure of passenger airlines for aircraft maintenance outsourcing as they relate to the total airline aircraft maintenance expenditures. Aircraft accident, incident, and pilot deviation rates used in the evaluation were the yearly number of accidents, incidents, and pilot deviations per miles flown. The Pearson r-values were calculated to measure the linear relationship strength between the variables. There were no statistically significant correlation findings for accidents, r(174)=0.065, p=0.393, and incidents, r(174)=0.020, p=0.793. However, there was a statistically significant correlation for pilot deviation rates, r(174)=0.204, p=0.007 thus indicating a statistically significant correlation between maintenance outsourcing rates and pilot deviation rates. The calculated R square value of 0.042 represents the variance that can be accounted for in aircraft pilot deviation rates by examining the variance in aircraft maintenance outsourcing rates; accordingly, 95.8% of the variance is unexplained. Suggestions for future research include

p - n junction diodes fabricated from isolated electrospun fibers of (P(NDI2ODT2)) and an inorganic p-doped semiconductor

Science.gov (United States)

Rosado, Alexander; Pinto, Nicholas

2013-03-01

A simple method to fabricate, under ambient conditions and within seconds, p - n diodes using an individual electrospun poly{[N, N'-bis(2-octyldodecyl)-naphthalene-1,4,5,8-bis(dicarboximide)-2,6-diyl]-alt-5,5'-(2,2'-bithiophene)}-(P(NDI2ODT2)) fiber and a commercially available p-doped Si/SiO2 substrate is presented. Band bending at the fiber/Si+ interface leads to asymmetric I-V characteristic curves resembling that of a diode. The diode turn-on voltage was in the range 1V and was unaffected via UV light irradiation. The rectification ratio however could be tuned reversibly thereby making this device multifunctional. In addition to being a rectifier, the advantage of our design is the complete exposure of the rectifying junction to the surrounding environment. This has the advantage of making them attractive candidates in the potential fabrication of low power, sensitive and rapid response photo-sensors. NSF

System for indicating fuel-efficient aircraft altitude

Science.gov (United States)

Gary, B. L. (Inventor)

1984-01-01

A method and apparatus are provided for indicating the altitude at which an aircraft should fly so the W/d ratio (weight of the aircraft divided by the density of air) more closely approaches the optimum W/d for the aircraft. A passive microwave radiometer on the aircraft is directed at different angles with respect to the horizon to determine the air temperature, and therefore the density of the air, at different altitudes. The weight of the aircraft is known. The altitude of the aircraft is changed to fly the aircraft at an altitude at which is W/d ratio more closely approaches the optimum W/d ratio for that aircraft.

150 Passenger Commercial Aircraft

Science.gov (United States)

Bucovsky, Adrian; Romli, Fairuz I.; Rupp, Jessica

2002-01-01

It has been projected that the need for a short-range mid-sized, aircraft is increasing. The future strategy to decrease long-haul flights will increase the demand for short-haul flights. Since passengers prefer to meet their destinations quickly, airlines will increase the frequency of flights, which will reduce the passenger load on the aircraft. If a point-to-point flight is not possible, passengers will prefer only a one-stop short connecting flight to their final destination. A 150-passenger aircraft is an ideal vehicle for these situations. It is mid-sized aircraft and has a range of 3000 nautical miles. This type of aircraft would market U.S. domestic flights or inter-European flight routes. The objective of the design of the 150-passenger aircraft is to minimize fuel consumption. The configuration of the aircraft must be optimized. This aircraft must meet CO2 and NOx emissions standards with minimal acquisition price and operating costs. This report contains all the work that has been performed for the completion of the design of a 150 passenger commercial aircraft. The methodology used is the Technology Identification, Evaluation, and Selection (TIES) developed at Georgia Tech Aerospace Systems Design laboratory (ASDL). This is an eight-step conceptual design process to evaluate the probability of meeting the design constraints. This methodology also allows for the evaluation of new technologies to be implemented into the design. The TIES process begins with defining the problem with a need established and a market targeted. With the customer requirements set and the target values established, a baseline concept is created. Next, the design space is explored to determine the feasibility and viability of the baseline aircraft configuration. If the design is neither feasible nor viable, new technologies can be implemented to open up the feasible design space and allow for a plausible solution. After the new technologies are identified, they must be evaluated

The Power for Flight: NASA's Contributions to Aircraft Propulsion

Science.gov (United States)

Kinney, Jeremy R.

2017-01-01

The New York Times announced America's entry into the 'long awaited' Jet Age when a Pan American (Pan Am) World Airways Boeing 707 airliner left New York for Paris on October 26, 1958. Powered by four turbojet engines, the 707 offered speed, more nonstop flights, and a smoother and quieter travel experience compared to newly antiquated propeller airliners. With the Champs-Elysees only 6 hours away, humankind had entered into a new and exciting age in which the shrinking of the world for good was no longer a daydream. Fifty years later, the New York Times declared the second coming of a 'cleaner, leaner' Jet Age. Decades-old concerns over fuel efficiency, noise, and emissions shaped this new age as the aviation industry had the world poised for 'a revolution in jet engines'. Refined turbofans incorporating the latest innovations would ensure that aviation would continue to enable a worldwide transportation network. At the root of many of the advances over the preceding 50 years was the National Aeronautics and Space Administration (NASA). On October 1, 1958, just a few weeks before the flight of that Pan Am 707, NASA came into existence. Tasked with establishing a national space program as part of a Cold War competition between the United States and the Soviet Union, NASA is often remembered in popular memory first for putting the first human beings on the Moon in July 1969, followed by running the successful 30-year Space Shuttle Program and by landing the Rover Curiosity on Mars in August 2012. What many people do not recognize is the crucial role the first 'A' in NASA played in the development of aircraft since the Agency's inception. Innovations shaping the aerodynamic design, efficient operation, and overall safety of aircraft made NASA a vital element of the American aviation industry even though they remained unknown to the public. This is the story of one facet of NASA's many contributions to commercial, military, and general aviation: the development of

Aircraft noise, air pollution, and mortality from myocardial infarction.

Science.gov (United States)

Huss, Anke; Spoerri, Adrian; Egger, Matthias; Röösli, Martin

2010-11-01

Myocardial infarction has been associated with both transportation noise and air pollution. We examined residential exposure to aircraft noise and mortality from myocardial infarction, taking air pollution into account. We analyzed the Swiss National Cohort, which includes geocoded information on residence. Exposure to aircraft noise and air pollution was determined based on geospatial noise and air-pollution (PM10) models and distance to major roads. We used Cox proportional hazard models, with age as the timescale. We compared the risk of death across categories of A-weighted sound pressure levels (dB(A)) and by duration of living in exposed corridors, adjusting for PM10 levels, distance to major roads, sex, education, and socioeconomic position of the municipality. We analyzed 4.6 million persons older than 30 years who were followed from near the end of 2000 through December 2005, including 15,532 deaths from myocardial infarction (ICD-10 codes I 21, I 22). Mortality increased with increasing level and duration of aircraft noise. The adjusted hazard ratio comparing ≥60 dB(A) with noise. Aircraft noise was associated with mortality from myocardial infarction, with a dose-response relationship for level and duration of exposure. The association does not appear to be explained by exposure to particulate matter air pollution, education, or socioeconomic status of the municipality.

Fettered aircraft for using wind energy

Energy Technology Data Exchange (ETDEWEB)

Hoeppner, H.; Horvath, E.; Ulrich, S.

1980-08-28

The invention concerns an aircraft tethered by cables, whose balloon-shaped central body produces static and aerodynamic upthrust and which carries turbines, which are used to convert wind energy and to drive the aircraft. The purpose of the invention is to provide an aircraft, which will keep wind energy plant at the optimum height. A new type of aircraft is used to solve the problem, which, according to the invention, combines static upthrust, the production of aerodynamic upthrust, wind energy conversion, energy transport and forward drive in a technically integrated aircraft. If the use of windpower is interrupted, then if necessary the drive together with a remote control system provides controlled free flight of the aircraft. One variant of the object of the invention consists of a central, balloon-shaped body for upthrust, in which there are wind turbines driving electrical generators. According to the invention the motors required to start the wind turbines are of such dimensions that they will drive the turbines in free flight of the aircraft and thus provide forward drive of the aircraft. A power generating unit, consisting of an internal combustion engine and the starter motors switched over to generator operation is used to provide house service supplies for control and regulation of the aircraft.

Aircraft Capability Management

Science.gov (United States)

Mumaw, Randy; Feary, Mike

2018-01-01

This presentation presents an overview of work performed at NASA Ames Research Center in 2017. The work concerns the analysis of current aircraft system management displays, and the initial development of an interface for providing information about aircraft system status. The new interface proposes a shift away from current aircraft system alerting interfaces that report the status of physical components, and towards displaying the implications of degradations on mission capability. The proposed interface describes these component failures in terms of operational consequences of aircraft system degradations. The research activity was an effort to examine the utility of different representations of complex systems and operating environments to support real-time decision making of off-nominal situations. A specific focus was to develop representations that provide better integrated information to allow pilots to more easily reason about the operational consequences of the off-nominal situations. The work is also seen as a pathway to autonomy, as information is integrated and understood in a form that automated responses could be developed for the off-nominal situations in the future.

Novel matrix resins for composites for aircraft primary structures, phase 1

Science.gov (United States)

Woo, Edmund P.; Puckett, P. M.; Maynard, S.; Bishop, M. T.; Bruza, K. J.; Godschalx, J. P.; Mullins, M. J.

1992-01-01

The objective of the contract is the development of matrix resins with improved processability and properties for composites for primarily aircraft structures. To this end, several resins/systems were identified for subsonic and supersonic applications. For subsonic aircraft, a series of epoxy resins suitable for RTM and powder prepreg was shown to give composites with about 40 ksi compressive strength after impact (CAI) and 200 F/wet mechanical performance. For supersonic applications, a thermoplastic toughened cyanate prepreg system has demonstrated excellent resistance to heat aging at 360 F for 4000 hours, 40 ksi CAI and useful mechanical properties at greater than or equal to 310 F. An AB-BCB-maleimide resin was identified as a leading candidate for the HSCT. Composite panels fabricated by RTM show CAI of approximately 50 ksi, 350 F/wet performance and excellent retention of mechanical properties after aging at 400 F for 4000 hours.

Essentials of aircraft armaments

CERN Document Server

Kaushik, Mrinal

2017-01-01

This book aims to provide a complete exposure about armaments from their design to launch from the combat aircraft. The book details modern ammunition and their tactical roles in warfare. The proposed book discusses aerodynamics, propulsion, structural as well as navigation, control, and guidance of aircraft armament. It also introduces the various types of ammunition developed by different countries and their changing trends. The book imparts knowledge in the field of design, and development of aircraft armaments to aerospace engineers and covers the role of the United Nations in peacekeeping and disarmament. The book will be very useful to researchers, students, and professionals working in design and manufacturing of aircraft armaments. The book will also serve air force and naval aspirants, and those interested in working on defence research and developments organizations. .

Evolution of Flying Qualities Analysis: Problems for a New Generation of Aircraft

Science.gov (United States)

2010-03-29

speed. . . Inability to balance and steer still confronts students of the flying problem . . .When this one feature has been worked out, the age of...30 −20 −10 0 10 20 M ag ni tu de ( dB ) 10 −1 10 0 10 1 10 2 −180 −135 −90 −45 0 P ha se ( de g) Bode Diagram, ω n =4, ζ = 0.65 Frequency (rad/sec... Unicorn Silverfox Vertex SPAARO C 152 R ey no ld s N um be r Gross Takeoff Weight (lbs) Comparison of Aircraft Figure 5.4: Aircraft operational

Hydrogen Storage for Aircraft Applications Overview

Science.gov (United States)

Colozza, Anthony J.; Kohout, Lisa (Technical Monitor)

2002-01-01

Advances in fuel cell technology have brought about their consideration as sources of power for aircraft. This power can be utilized to run aircraft systems or even provide propulsion power. One of the key obstacles to utilizing fuel cells on aircraft is the storage of hydrogen. An overview of the potential methods of hydrogen storage was compiled. This overview identifies various methods of hydrogen storage and points out their advantages and disadvantages relative to aircraft applications. Minimizing weight and volume are the key aspects to storing hydrogen within an aircraft. An analysis was performed to show how changes in certain parameters of a given storage system affect its mass and volume.

The effects of road traffic and aircraft noise exposure on children′s episodic memory: The RANCH Project

Directory of Open Access Journals (Sweden)

Mark Matheson

2010-01-01

Full Text Available Previous studies have found that chronic exposure to aircraft noise has a negative effect on children′s performance on tests of episodic memory. The present study extended the design of earlier studies in three ways: firstly, by examining the effects of two noise sources, aircraft and road traffic, secondly, by examining exposure-effect relationships, and thirdly, by carrying out parallel field studies in three European countries, allowing cross-country comparisons to be made. A total of 2844 children aged between 8 years 10 months and 12 years 10 months (mean age 10 years 6 months completed classroom-based tests of cued recall, recognition memory and prospective memory. Questionnaires were also completed by the children and their parents in order to provide information about socioeconomic context. Multilevel modeling analysis revealed aircraft noise to be associated with an impairment of recognition memory in a linear exposure-effect relationship. The analysis also found road traffic noise to be associated with improved performance on cued recall in a linear exposure-effect relationship. No significant association was found between exposure to aircraft noise and cued recall or prospective memory. Likewise, no significant association was found between road traffic noise and recognition or prospective memory. Taken together, these findings indicate that exposure to aircraft noise and road traffic noise can impact on certain aspects of children′s episodic memory.

Estimation of nuclear power plant aircraft hazards

International Nuclear Information System (INIS)

Gottlieb, P.

1978-01-01

The standard procedures for estimating aircraft risk to nuclear power plants provide a conservative estimate, which is adequate for most sites, which are not close to airports or heavily traveled air corridors. For those sites which are close to facilities handling large numbers of aircraft movements (airports or corridors), a more precise estimate of aircraft impact frequency can be obtained as a function of aircraft size. In many instances the very large commercial aircraft can be shown to have an acceptably small impact frequency, while the very small general aviation aircraft will not produce sufficiently serious impact to impair the safety-related functions. This paper examines the in between aircraft: primarily twin-engine, used for business, pleasure, and air taxi operations. For this group of aircraft the total impact frequency was found to be approximately once in one million years, the threshold above which further consideration of specific safety-related consequences would be required

Aircraft Carrier Exposure Testing of Aircraft Materials

National Research Council Canada - National Science Library

Lee, Eui

2004-01-01

.... Test and control specimens were affixed on exposure racks and installed on aircraft carriers to compare adhesive bonding primers for aluminum and to determine the static property behavior of various...

Identification of Aircraft Hazards

International Nuclear Information System (INIS)

K. Ashley

2006-01-01

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

14 CFR 49.11 - FAA Aircraft Registry.

Science.gov (United States)

2010-01-01

... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false FAA Aircraft Registry. 49.11 Section 49.11... AIRCRAFT TITLES AND SECURITY DOCUMENTS General § 49.11 FAA Aircraft Registry. To be eligible for recording, a conveyance must be mailed to the FAA Aircraft Registry, Department of Transportation, Post Office...

FAA Fluorescent Penetrant Laboratory Inspections

Energy Technology Data Exchange (ETDEWEB)

WINDES,CONNOR L.; MOORE,DAVID G.

2000-08-02

The Federal Aviation Administration Airworthiness Assurance NDI Validation Center currently assesses the capability of various non-destructive inspection (NDI) methods used for analyzing aircraft components. The focus of one such exercise is to evaluate the sensitivity of fluorescent liquid penetrant inspection. A baseline procedure using the water-washable fluorescent penetrant method defines a foundation for comparing the brightness of low cycle fatigue cracks in titanium test panels. The analysis of deviations in the baseline procedure will determine an acceptable range of operation for the steps in the inspection process. The data also gives insight into the depth of each crack and which step(s) of the inspection process most affect penetrant sensitivities. A set of six low cycle fatigue cracks produced in 6.35-mm thick Ti-6Al-4V specimens was used to conduct the experiments to produce sensitivity data. The results will document the consistency of the crack readings and compare previous experiments to find the best parameters for water-washable penetrant.

Annoyance by aircraft noise and fear of overflying aircraft in relation to attitudes toward the environment and community

Science.gov (United States)

Loeb, M.; Moran, S. V.

1977-01-01

It has been suggested that expressions of annoyance attributable to aircraft noise may reflect in part fear of aircraft overflights and possible crashes. If this is true, then residents of areas where crashes have occurred should express more annoyance. To test this hypothesis, 50 residents of an Albany, New York area where an aircraft crash producing fatalities recently occurred and 50 residents of a comparable nearby area without such a history, were asked to respond to a 'Quality of Life Questionnaire.' Among the items were some designed to test annoyance by noise and fear of aircraft overflights. It was predicted that those in the crash area would express more fear and would more often identify aircraft as a noise source. These hypotheses were sustained. A near-replication was carried out in Louisville, Kentucky; results were much the same. Analyses indicated that for the crash-area groups, there was associating of aircraft fear and noise annoyance responses; this was true to an apparently lesser extent for non-crash groups. The greater annoyance of crash groups by aircraft community noise apparently does not carry over to situations in which aircraft noise is assessed in the laboratory.

The Aircraft Morphing Program

Science.gov (United States)

Wlezien, R. W.; Horner, G. C.; McGowan, A. R.; Padula, S. L.; Scott, M. A.; Silcox, R. J.; Simpson, J. O.

1998-01-01

In the last decade smart technologies have become enablers that cut across traditional boundaries in materials science and engineering. Here we define smart to mean embedded actuation, sensing, and control logic in a tightly coupled feedback loop. While multiple successes have been achieved in the laboratory, we have yet to see the general applicability of smart devices to real aircraft systems. The NASA Aircraft Morphing program is an attempt to couple research across a wide range of disciplines to integrate smart technologies into high payoff aircraft applications. The program bridges research in seven individual disciplines and combines the effort into activities in three primary program thrusts. System studies are used to assess the highest- payoff program objectives, and specific research activities are defined to address the technologies required for development of smart aircraft systems. In this paper we address the overall program goals and programmatic structure, and discuss the challenges associated with bringing the technologies to fruition.

75 FR 41986 - Certification of Aircraft and Airmen for the Operation of Light-Sport Aircraft; Modifications to...

Science.gov (United States)

2010-07-20

...- Sport Aircraft; Modifications to Rules for Sport Pilots and Flight Instructors With a Sport Pilot Rating... rule; OMB approval of information collection. SUMMARY: This document announces the Office of Management... rule, ``Certification of Aircraft and Airmen for the Operation of Light-Sport Aircraft; Modifications...

Aircraft Cabin Environmental Quality Sensors

Energy Technology Data Exchange (ETDEWEB)

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

2010-05-06

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

Impact analysis of composite aircraft structures

Science.gov (United States)

Pifko, Allan B.; Kushner, Alan S.

1993-01-01

The impact analysis of composite aircraft structures is discussed. Topics discussed include: background remarks on aircraft crashworthiness; comments on modeling strategies for crashworthiness simulation; initial study of simulation of progressive failure of an aircraft component constructed of composite material; and research direction in composite characterization for impact analysis.

8 CFR 1280.21 - Seizure of aircraft.

Science.gov (United States)

2010-01-01

... 8 Aliens and Nationality 1 2010-01-01 2010-01-01 false Seizure of aircraft. 1280.21 Section 1280... REGULATIONS IMPOSITION AND COLLECTION OF FINES § 1280.21 Seizure of aircraft. Seizure of an aircraft under the... that its value is less than the amount of the fine which may be imposed. If seizure of an aircraft for...

8 CFR 280.21 - Seizure of aircraft.

Science.gov (United States)

2010-01-01

... 8 Aliens and Nationality 1 2010-01-01 2010-01-01 false Seizure of aircraft. 280.21 Section 280.21... OF FINES § 280.21 Seizure of aircraft. Seizure of an aircraft under the authority of section 239 of... than the amount of the fine which may be imposed. If seizure of an aircraft for violation of section...

GRAPHICAL MODELS OF THE AIRCRAFT MAINTENANCE PROCESS

Directory of Open Access Journals (Sweden)

Stanislav Vladimirovich Daletskiy

2017-01-01

Full Text Available The aircraft maintenance is realized by a rapid sequence of maintenance organizational and technical states, its re- search and analysis are carried out by statistical methods. The maintenance process concludes aircraft technical states con- nected with the objective patterns of technical qualities changes of the aircraft as a maintenance object and organizational states which determine the subjective organization and planning process of aircraft using. The objective maintenance pro- cess is realized in Maintenance and Repair System which does not include maintenance organization and planning and is a set of related elements: aircraft, Maintenance and Repair measures, executors and documentation that sets rules of their interaction for maintaining of the aircraft reliability and readiness for flight. The aircraft organizational and technical states are considered, their characteristics and heuristic estimates of connection in knots and arcs of graphs and of aircraft organi- zational states during regular maintenance and at technical state failure are given. It is shown that in real conditions of air- craft maintenance, planned aircraft technical state control and maintenance control through it, is only defined by Mainte- nance and Repair conditions at a given Maintenance and Repair type and form structures, and correspondingly by setting principles of Maintenance and Repair work types to the execution, due to maintenance, by aircraft and all its units mainte- nance and reconstruction strategies. The realization of planned Maintenance and Repair process determines the one of the constant maintenance component. The proposed graphical models allow to reveal quantitative correlations between graph knots to improve maintenance processes by statistical research methods, what reduces manning, timetable and expenses for providing safe civil aviation aircraft maintenance.

Environmental Assessment (EA): Proposed Aircraft Power Systems Repair Transformation Facility, Hill Air Force Base, Utah

Science.gov (United States)

2007-05-16

and silicon carbide; spent elastic abrasive media; rags and wipes from the NDI process ; and unused scraps of TIG welding wire. Dust from the thermal...used, which would not be expected to produce regulated air emissions. For this process , no air quality permit updates are anticipated. • Welding ...The electron beam welding equipment would not be expected to produce regulated air emissions. The tungsten inert gas ( TIG ) welding equipment would

Principles for Aircraft Energy Mapping

OpenAIRE

Berg, Frederick T N

2013-01-01

An increasing emphasis on energy eciency in aircraft systems has in recentyears led to greater interest in integrated design and optimisation withinthe industry. New tools are needed to understand, compare and manage energyuse of an aircraft throughout its design and operation. This thesis describes a new methodology to meet this need: aircraft exergy mapping.The choice of exergy, a 2nd law metric, to describe the energy ows is fundamental to the methodology, providing numerous advantages ove...

NDT applications in the aircraft industry

International Nuclear Information System (INIS)

Aguilar, E.C.

1994-01-01

Non-destructive testing (NDT) in the aircraft industry is used primarily to detect process defects in the manufacturing stage and failure defects in the in-service stage. Inspection techniques such as X- or gamma ray radiography are used for examination. Eddy current and ultrasonic are applied for examination, fluorescent penetrant and magnetic particles are applied for examination of aircraft and engine. With the wide scope of application, this paper discussed one type of NDT that is much used in aircraft being the latest technique in aircraft manufacturing. 1 fig

Composite materials for aircraft structures

National Research Council Canada - National Science Library

Baker, A. A; Dutton, Stuart; Kelly, Donald

2004-01-01

... materials for aircraft structures / Alan Baker, Stuart Dutton, and Donald Kelly- 2nd ed. p. cm. - (Education series) Rev. ed. of: Composite materials for aircraft structures / edited by B. C. Hos...

IDENTIFICATION OF AIRCRAFT HAZARDS

International Nuclear Information System (INIS)

K.L. Ashley

2005-01-01

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

Identification of Aircraft Hazards

Energy Technology Data Exchange (ETDEWEB)

K. Ashley

2006-12-08

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

31 CFR 560.528 - Aircraft safety.

Science.gov (United States)

2010-07-01

... 31 Money and Finance: Treasury 3 2010-07-01 2010-07-01 false Aircraft safety. 560.528 Section 560..., Authorizations and Statements of Licensing Policy § 560.528 Aircraft safety. Specific licenses may be issued on a... the safety of civil aviation and safe operation of U.S.-origin commercial passenger aircraft. ...

Design definition study of a lift/cruise fan technology V/STOL aircraft. Volume 1: Navy operational aircraft

Science.gov (United States)

1975-01-01

Aircraft were designed and sized to meet Navy mission requirements. Five missions were established for evaluation: anti-submarine warfare (ASW), surface attack (SA), combat search and rescue (CSAR), surveillance (SURV), and vertical on-board delivery (VOD). All missions were performed with a short takeoff and a vertical landing. The aircraft were defined using existing J97-GE gas generators or reasonable growth derivatives in conjunction with turbotip fans reflecting LF460 type technology. The multipurpose aircraft configuration established for U.S. Navy missions utilizes the turbotip driven lift/cruise fan concept for V/STOL aircraft.

Alternate Fuels for Use in Commercial Aircraft

Science.gov (United States)

Daggett, David L.; Hendricks, Robert C.; Walther, Rainer; Corporan, Edwin

2008-01-01

The engine and aircraft Research and Development (R&D) communities have been investigating alternative fueling in near-term, midterm, and far-term aircraft. A drop in jet fuel replacement, consisting of a kerosene (Jet-A) and synthetic fuel blend, will be possible for use in existing and near-term aircraft. Future midterm aircraft may use a biojet and synthetic fuel blend in ultra-efficient airplane designs. Future far-term engines and aircraft in 50-plus years may be specifically designed to use a low- or zero-carbon fuel. Synthetic jet fuels from coal, natural gas, or other hydrocarbon feedstocks are very similar in performance to conventional jet fuel, yet the additional CO2 produced during the manufacturing needs to be permanently sequestered. Biojet fuels need to be developed specifically for jet aircraft without displacing food production. Envisioned as midterm aircraft fuel, if the performance and cost liabilities can be overcome, biofuel blends with synthetic jet or Jet-A fuels have near-term potential in terms of global climatic concerns. Long-term solutions address dramatic emissions reductions through use of alternate aircraft fuels such as liquid hydrogen or liquid methane. Either of these new aircraft fuels will require an enormous change in infrastructure and thus engine and airplane design. Life-cycle environmental questions need to be addressed.

Aircraft gas turbines

Energy Technology Data Exchange (ETDEWEB)

Arai, M [Kawasaki Heavy Industries Ltd., Kobe (Japan)

1995-03-01

Recently the international relationship has been playing an important role in the research, development and production of the aircraft gas turbine. The YSX, which is supposed to be the 100-seat class commercial aircraft, has been planned by Japan Aircraft Development (JADC) as an international cooperative project. Recently many western aeroengine companies have offered the collaboration of small turbofan engines which would be installed on YSX to Japanese aeroengine companies (IHI, KHI and MHI). The YSX is powered by 16,000-20,000 1bs thrust class engines. As for medium turbofan engine (V2500), the V 2500 family of 22,000 to 30,000 1bs thrust has been developed since 1983 through international collaboration by seven aeroengine companies in five nations. In this paper, the recent Japan`s activities of the research, development and production with viewing the world-wide movement, are described. 6 figs.

Hazards from aircraft

International Nuclear Information System (INIS)

Grund, J.E.; Hornyik, K.

1975-01-01

The siting of nuclear power plants has created innumerable environmental concerns. Among the effects of the ''man-made environment'' one of increasing importance in recent nuclear plant siting hazards analysis has been the concern about aircraft hazards to the nuclear plant. These hazards are of concern because of the possibility that an aircraft may have a malfunction and crash either near the plant or directly into it. Such a crash could be postulated to result, because of missile and/or fire effects, in radioactive releases which would endanger the public health and safety. The majority of studies related to hazards from air traffic have been concerned with the determination of the probability associated with an aircraft striking vulnerable portions of a given plant. Other studies have focused on the structural response to such a strike. This work focuses on the problem of strike probability. 13 references

Aircraft Carriers

DEFF Research Database (Denmark)

Nødskov, Kim; Kværnø, Ole

as their purchases of aircraft carrier systems, makes it more than likely that the country is preparing such an acquisition. China has territorial disputes in the South China Sea over the Spratly Islands and is also worried about the security of its sea lines of communications, by which China transports the majority......, submarines, aircraft and helicopters, is not likely to be fully operational and war-capable until 2020, given the fact that China is starting from a clean sheet of paper. The United States of America (USA), the United Kingdom (UK), Russia and India are currently building or have made decisions to build new...

Perspectives on Highly Adaptive or Morphing Aircraft

Science.gov (United States)

McGowan, Anna-Maria R.; Vicroy, Dan D.; Busan, Ronald C.; Hahn, Andrew S.

2009-01-01

The ability to adapt to different flight conditions has been fundamental to aircraft design since the Wright Brothers first flight. Over a hundred years later, unconventional aircraft adaptability, often called aircraft morphing has become a topic of considerable renewed interest. In the past two decades, this interest has been largely fuelled by advancements in multi-functional or smart materials and structures. However, highly adaptive or morphing aircraft is certainly a cross-discipline challenge that stimulates a wide range of design possibilities. This paper will review some of the history of morphing aircraft including recent research programs and discuss some perspectives on this work.

Small Transport Aircraft Technology /STAT/ Propulsion Study

Science.gov (United States)

Heldenbrand, R. W.; Baerst, C. F.; Rowse, J. H.

1980-01-01

The NASA Small Transport Aircraft Technology (STAT) Propulsion Study was established to identify technology requirements and define the research and development required for new commuter aircraft. Interim results of the studies defined mission and design characteristics for 30- and 50-passenger aircraft. Sensitivities were defined that relate changes in engine specific fuel consumption (SFC), weight, and cost (including maintenance) to changes in the aircraft direct operating cost (DOC), takeoff gross weight, and empty weight. A comparison of performance and economic characteristics is presented between aircraft powered by 1980 production engines and those powered by a 1990 advanced technology baseline engine.

Aircraft vulnerability analysis by modeling and simulation

Science.gov (United States)

Willers, Cornelius J.; Willers, Maria S.; de Waal, Alta

2014-10-01

Infrared missiles pose a significant threat to civilian and military aviation. ManPADS missiles are especially dangerous in the hands of rogue and undisciplined forces. Yet, not all the launched missiles hit their targets; the miss being either attributable to misuse of the weapon or to missile performance restrictions. This paper analyses some of the factors affecting aircraft vulnerability and demonstrates a structured analysis of the risk and aircraft vulnerability problem. The aircraft-missile engagement is a complex series of events, many of which are only partially understood. Aircraft and missile designers focus on the optimal design and performance of their respective systems, often testing only in a limited set of scenarios. Most missiles react to the contrast intensity, but the variability of the background is rarely considered. Finally, the vulnerability of the aircraft depends jointly on the missile's performance and the doctrine governing the missile's launch. These factors are considered in a holistic investigation. The view direction, altitude, time of day, sun position, latitude/longitude and terrain determine the background against which the aircraft is observed. Especially high gradients in sky radiance occur around the sun and on the horizon. This paper considers uncluttered background scenes (uniform terrain and clear sky) and presents examples of background radiance at all view angles across a sphere around the sensor. A detailed geometrical and spatially distributed radiometric model is used to model the aircraft. This model provides the signature at all possible view angles across the sphere around the aircraft. The signature is determined in absolute terms (no background) and in contrast terms (with background). It is shown that the background significantly affects the contrast signature as observed by the missile sensor. A simplified missile model is constructed by defining the thrust and mass profiles, maximum seeker tracking rate, maximum

Daedalus Project's Light Eagle - Human powered aircraft

Science.gov (United States)

1987-01-01

The Michelob Light Eagle is seen here in flight over Rogers Dry Lake at the NASA Dryden Flight Research Center, Edwards, California. The Light Eagle and Daedalus human powered aircraft were testbeds for flight research conducted at Dryden between January 1987 and March 1988. These unique aircraft were designed and constructed by a group of students, professors, and alumni of the Massachusetts Institute of Technology within the context of the Daedalus project. The construction of the Light Eagle and Daedalus aircraft was funded primarily by the Anheuser Busch and United Technologies Corporations, respectively, with additional support from the Smithsonian Air and Space Museum, MIT, and a number of other sponsors. To celebrate the Greek myth of Daedalus, the man who constructed wings of wax and feathers to escape King Minos, the Daedalus project began with the goal of designing, building and testing a human-powered aircraft that could fly the mythical distance, 115 km. To achieve this goal, three aircraft were constructed. The Light Eagle was the prototype aircraft, weighing 92 pounds. On January 22, 1987, it set a closed course distance record of 59 km, which still stands. Also in January of 1987, the Light Eagle was powered by Lois McCallin to set the straight distance, the distance around a closed circuit, and the duration world records for the female division in human powered vehicles. Following this success, two more aircraft were built, the Daedalus 87 and Daedalus 88. Each aircraft weighed approximately 69 pounds. The Daedalus 88 aircraft was the ship that flew the 199 km from the Iraklion Air Force Base on Crete in the Mediterranean Sea, to the island of Santorini in 3 hours, 54 minutes. In the process, the aircraft set new records in distance and endurance for a human powered aircraft. The specific areas of flight research conducted at Dryden included characterizing the rigid body and flexible dynamics of the Light Eagle, investigating sensors for an

Structural design for aircraft impact loading

International Nuclear Information System (INIS)

Schmidt, R.; Heckhausen, H.; Chen, C.; Rieck, P.J.; Lemons, G.W.

1977-01-01

The Soft Shell-Hardcore approach to nuclear power plant auxiliary structure design was developed to attenuate the crash effects of impacting aircraft. This report is an initial investigation into defining the important structural features involved that would allow the Soft Shell-Hardcore design to successfully sustain the postulated aircraft impact. Also specified for purposes of this study are aircraft impact locations and the type and velocity of impacting aircraft. The purpose of this initial investigation is to determine the feasibility of the two 0.5 m thick walls of the Soft Shell with the simplest possible mathematical model

GRAPHICAL MODELS OF THE AIRCRAFT MAINTENANCE PROCESS

OpenAIRE

Stanislav Vladimirovich Daletskiy; Stanislav Stanislavovich Daletskiy

2017-01-01

The aircraft maintenance is realized by a rapid sequence of maintenance organizational and technical states, its re- search and analysis are carried out by statistical methods. The maintenance process concludes aircraft technical states con- nected with the objective patterns of technical qualities changes of the aircraft as a maintenance object and organizational states which determine the subjective organization and planning process of aircraft using. The objective maintenance pro- cess is ...

A Grounded Theory Study of Aircraft Maintenance Technician Decision-Making

Science.gov (United States)

Norcross, Robert

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

Mission Analysis and Aircraft Sizing of a Hybrid-Electric Regional Aircraft

Science.gov (United States)

Antcliff, Kevin R.; Guynn, Mark D.; Marien, Ty V.; Wells, Douglas P.; Schneider, Steven J.; Tong, Michael T.

2016-01-01

The purpose of this study was to explore advanced airframe and propulsion technologies for a small regional transport aircraft concept (approximately 50 passengers), with the goal of creating a conceptual design that delivers significant cost and performance advantages over current aircraft in that class. In turn, this could encourage airlines to open up new markets, reestablish service at smaller airports, and increase mobility and connectivity for all passengers. To meet these study goals, hybrid-electric propulsion was analyzed as the primary enabling technology. The advanced regional aircraft is analyzed with four levels of electrification, 0 percent electric with 100 percent conventional, 25 percent electric with 75 percent conventional, 50 percent electric with 50 percent conventional, and 75 percent electric with 25 percent conventional for comparison purposes. Engine models were developed to represent projected future turboprop engine performance with advanced technology and estimates of the engine weights and flowpath dimensions were developed. A low-order multi-disciplinary optimization (MDO) environment was created that could capture the unique features of parallel hybrid-electric aircraft. It is determined that at the size and range of the advanced turboprop: The battery specific energy must be 750 watt-hours per kilogram or greater for the total energy to be less than for a conventional aircraft. A hybrid vehicle would likely not be economically feasible with a battery specific energy of 500 or 750 watt-hours per kilogram based on the higher gross weight, operating empty weight, and energy costs compared to a conventional turboprop. The battery specific energy would need to reach 1000 watt-hours per kilogram by 2030 to make the electrification of its propulsion an economically feasible option. A shorter range and/or an altered propulsion-airframe integration could provide more favorable results.

Aircraft vulnerability analysis by modelling and simulation

CSIR Research Space (South Africa)

Willers, CJ

2014-09-01

Full Text Available attributable to misuse of the weapon or to missile performance restrictions. This paper analyses some of the factors affecting aircraft vulnerability and demonstrates a structured analysis of the risk and aircraft vulnerability problem. The aircraft...

Analyses of Aircraft Responses to Atmospheric Turbulence

NARCIS (Netherlands)

Van Staveren, W.H.J.J.

2003-01-01

The response of aircraft to stochastic atmospheric turbulence plays an important role in aircraft-design (load calculations), Flight Control System (FCS) design and flight-simulation (handling qualities research and pilot training). In order to simulate these aircraft responses, an accurate

Common factors in the withdrawal of European aircraft manufacturers from the regional aircraft market

NARCIS (Netherlands)

Heerkens, Johannes M.G.; de Bruijn, E.J.; Steenhuis, H.J.

2010-01-01

We investigate whether there were common causes for the withdrawal from the regional aircraft market of three established manufacturers (BAE Systems, Fokker and Saab), while competitors thrived. We focus on the markets for 50- and 100-seat aircraft. One cause concerning the 50-seat market was the

Advanced technology for future regional transport aircraft

Science.gov (United States)

Williams, L. J.

1982-01-01

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.

Control of Next Generation Aircraft and Wind Turbines

Science.gov (United States)

Frost, Susan

2010-01-01

The first part of this talk will describe some of the exciting new next generation aircraft that NASA is proposing for the future. These aircraft are being designed to reduce aircraft fuel consumption and environmental impact. Reducing the aircraft weight is one approach that will be used to achieve these goals. A new control framework will be presented that enables lighter, more flexible aircraft to maintain aircraft handling qualities, while preventing the aircraft from exceeding structural load limits. The second part of the talk will give an overview of utility-scale wind turbines and their control. Results of collaboration with Dr. Balas will be presented, including new theory to adaptively control the turbine in the presence of structural modes, with the focus on the application of this theory to a high-fidelity simulation of a wind turbine.

Aircraft height estimation using 2-D radar

CSIR Research Space (South Africa)

Hakl, H

2010-01-01

Full Text Available A method to infer height information from an aircraft tracked with a single 2-D search radar is presented. The method assumes level flight in the target aircraft and a good estimate of the speed of the aircraft. The method yields good results...

Aircraft control surface failure detection and isolation using the OSGLR test. [orthogonal series generalized likelihood ratio

Science.gov (United States)

Bonnice, W. F.; Motyka, P.; Wagner, E.; Hall, S. R.

1986-01-01

The performance of the orthogonal series generalized likelihood ratio (OSGLR) test in detecting and isolating commercial aircraft control surface and actuator failures is evaluated. A modification to incorporate age-weighting which significantly reduces the sensitivity of the algorithm to modeling errors is presented. The steady-state implementation of the algorithm based on a single linear model valid for a cruise flight condition is tested using a nonlinear aircraft simulation. A number of off-nominal no-failure flight conditions including maneuvers, nonzero flap deflections, different turbulence levels and steady winds were tested. Based on the no-failure decision functions produced by off-nominal flight conditions, the failure detection and isolation performance at the nominal flight condition was determined. The extension of the algorithm to a wider flight envelope by scheduling on dynamic pressure and flap deflection is examined. Based on this testing, the OSGLR algorithm should be capable of detecting control surface failures that would affect the safe operation of a commercial aircraft. Isolation may be difficult if there are several surfaces which produce similar effects on the aircraft. Extending the algorithm over the entire operating envelope of a commercial aircraft appears feasible.

Combat aircraft noise

Science.gov (United States)

Sgarbozza, M.; Depitre, A.

1992-04-01

A discussion of the characteristics and the noise levels of combat aircraft and of a transport aircraft in taking off and landing are presented. Some methods of noise reduction are discussed, including the following: operational anti-noise procedures; and concepts of future engines (silent post-combustion and variable cycle). Some measurement results concerning the noise generated in flight at great speeds and low altitude will also be examined. Finally, the protection of the environment of French air bases against noise will be described and the possibilities of regulation examined.

Amphibious Aircraft

Data.gov (United States)

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

AIRCRAFT CONFLICTS RESOLUTION BY COURSE MANEUVERING

Directory of Open Access Journals (Sweden)

В. Харченко

2011-02-01

Full Text Available Enhancement of requirements for air traffic efficiency at increasing of flights intensity determines the necessity of development of new optimization methods for aircraft conflict resolutions. The statement of problem of optimal conflict resolutions at Cooperative Air Traffic Management was done. The method for optimal aircraft conflict  resolution by course maneuvering has been  developed. The method using dynamic programming provides planning of aircraft conflict-free trajectory with minimum length. The decomposition of conflict resolution process on phases and stages, definition of states, controls and recursive  equations for generation of optimal course control program were done. Computer modeling of aircraft conflict resolution by developed method was done

Fast Aircraft Turnaround Enabled by Reliable Passenger Boarding

Directory of Open Access Journals (Sweden)

Michael Schultz

2018-01-01

Full Text Available Future 4D aircraft trajectories demand comprehensive consideration of environmental, economic, and operational constraints, as well as reliable prediction of all aircraft-related processes. Mutual interdependencies between airports result in system-wide, far-reaching effects in the air traffic network (reactionary delays. To comply with airline/airport challenges over the day of operations, a change to an air-to-air perspective is necessary, with a specific focus on the aircraft ground operations as major driver for airline punctuality. Aircraft ground trajectories primarily consists of handling processes at the stand (deboarding, catering, fueling, cleaning, boarding, unloading, loading, which are defined as the aircraft turnaround. Turnaround processes are mainly controlled by ground handling, airport, or airline staff, except the aircraft boarding, which is driven by passengers’ experience and willingness/ability to follow the proposed boarding procedures. This paper provides an overview of the research done in the field of aircraft boarding and introduces a reliable, calibrated, and stochastic aircraft boarding model. The stochastic boarding model is implemented in a simulation environment to evaluate specific boarding scenarios using different boarding strategies and innovative technologies. Furthermore, the potential of a connected aircraft cabin as sensor network is emphasized, which could provide information on the current and future status of the boarding process.

Association of Patent Ductus Arteriosus Ligation With Death or Neurodevelopmental Impairment Among Extremely Preterm Infants

Science.gov (United States)

Mirea, Lucia; Rosenberg, Erin; Jang, Maximus; Ly, Linh; Church, Paige T.; Kelly, Edmond; Kim, S. Joseph; Jain, Amish; McNamara, Patrick J.; Shah, Prakesh S.

2017-01-01

Importance Observational studies have associated patent ductus arteriosus (PDA) ligation among preterm infants with adverse neonatal outcomes and neurodevelopmental impairment in early childhood, with a resultant secular trend away from surgical treatment. However, to our knowledge, studies have inadequately addressed sources of residual bias, including survival bias and major neonatal morbidities arising before exposure to ligation. Objective Evaluate the association between PDA ligation vs medical management and neonatal and neurodevelopmental outcomes. Design, Setting, and Participants This retrospective cohort study of preterm infants younger than 28 weeks gestational age born between January 1, 2006, and December 31, 2012, with clinical and echocardiography diagnoses of hemodynamically significant PDA was conducted at 3 tertiary neonatal intensive care units and affiliated follow-up programs. Exposure Surgical ligation vs medical management. Main Outcomes and Measures The primary outcome was a composite of death or neurodevelopmental impairment (NDI) at 18 to 24 months corrected age. Secondary outcomes included death before discharge, NDI, moderate-severe chronic lung disease, and severe retinopathy of prematurity. Multivariable logistic regression analysis was used to adjust for perinatal and postnatal confounders. Results Of 754 infants with hemodynamically significant PDA (mean [standard deviation] gestational age 25.7 [1.2] weeks and birth weight 813 [183] grams), 184 (24%) underwent ligation. Infants who underwent ligation had a higher frequency of morbidities before PDA closure, including sepsis, necrotizing enterocolitis, and a dependence on mechanical ventilation. After adjusting for perinatal characteristics and preligation morbidities, there was no difference in the odds of death or NDI (adjusted odds ratio (aOR), 0.83; 95% CI, 0.52-1.32), NDI (aOR, 1.27; 95% CI, 0.78-2.06), chronic lung disease (aOR, 1.36; 95% CI, 0.78-2.39) or severe retinopathy of

Aircraft gas turbines

Energy Technology Data Exchange (ETDEWEB)

Sekido, T [Ishikawajima-Harima Heavy Industries, Co. Ltd., Tokyo (Japan)

1994-03-01

Current developmental activities of aircraft gas turbines in Japan are reviewed. V2500-A5 engine with thrust of 30,000 LBF is scheduled to be used for real aircraft in 1994, and intensive developmental activities are also proceeding in larger engines over 90,000 LBF. Recently, developmental programs of engines for 75-100 seat aircraft have been actively discussed, and Japanese engine makers are having discussions towards international collaboration. Such engines will be high bypass turbofans of 12,000-22,000 LBF. Development of SST/HST engines in a speed range from subsonic to Mach 5 is under the initiative of the Agency of Industrial Science and Technology. The Technical Research and Development Institute of Japan, Defence Agency achieved the target thrust of 3.4 tons in the small turbofan engine program, and the small turboshaft engine for small helicopters is also under development. Both National Aerospace Laboratory (NAL) and Institute of Space and Aeronautical Science (ISAS) are now conducting the research programs on turbo-ramjet engines under a component test phase. 1 fig.

14 CFR 47.19 - FAA Aircraft Registry.

Science.gov (United States)

2010-01-01

... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false FAA Aircraft Registry. 47.19 Section 47.19... REGISTRATION General § 47.19 FAA Aircraft Registry. Each application, request, notification, or other communication sent to the FAA under this Part must be mailed to the FAA Aircraft Registry, Department of...

Systematic analysis of aircraft separation requirements

Science.gov (United States)

Ennis, Rachelle Lea

2005-12-01

Minimum separation standards are necessary for safety in the air traffic control system. At the same time, minimum separation standards constrain the flow of air traffic and cause delays that translate to millions of dollars in fuel costs. Two necessary separation standards are defined. Then, practical methods for calculating the minimum required size of these separation standards are presented. First, the protected zone is considered. The protected zone represents a region around a given aircraft that no other aircraft should penetrate for the safety of both aircraft. It defines minimum separation requirements. Three major components of the protected zone and their interplays are identified: a vortex region, a safety buffer region, and a state-uncertainty region. A systematic procedure is devised for the analysis of the state-uncertainty region. In particular, models of trajectory controls are developed that can be used to represent different modes of pilot and/or autopilot controls, such as path feedback and non-path feedback. Composite protected zones under various conditions are estimated, and effective ways to reduce sizes of protected zones for advanced air traffic management are examined. In order to maintain minimum separation standards between two aircraft, proper avoidance maneuvers must be initiated before their relative separation reaches the minimum separation due to aircraft dynamics, controller and pilot response delays, etc. The concept of the required action threshold is presented. It is defined as the advanced time for which the conflict resolution process must begin in order to maintain minimum separation requirements. Five main segments in the process of conflict resolution are identified, discussed, and modeled: state information acquisition, comprehension and decision, communication, pilot response, and aircraft maneuver. Each of the five segments is modeled via a time constant. Time estimates for the first four segments are obtained from

Preliminary results on the fracture analysis of multi-site cracking of lap joints in aircraft skins

Science.gov (United States)

Beuth, J. L., Jr.; Hutchinson, John W.

1992-07-01

Results of a fracture mechanics analysis relevant to fatigue crack growth at rivets in lap joints of aircraft skins are presented. Multi-site damage (MSD) is receiving increased attention within the context of problems of aging aircraft. Fracture analyses previously carried out include small-scale modeling of rivet/skin interactions, larger-scale two-dimensional models of lap joints similar to that developed here, and full scale three-dimensional models of large portions of the aircraft fuselage. Fatigue testing efforts have included flat coupon specimens, two-dimensional lap joint tests, and full scale tests on specimens designed to closely duplicate aircraft sections. Most of this work is documented in the proceedings of previous symposia on the aging aircraft problem. The effect MSD has on the ability of skin stiffeners to arrest the growth of long skin cracks is a particularly important topic that remains to be addressed. One of the most striking features of MSD observed in joints of some test sections and in the joints of some of the older aircraft fuselages is the relative uniformity of the fatigue cracks from rivet to rivet along an extended row of rivets. This regularity suggests that nucleation of the cracks must not be overly difficult. Moreover, it indicates that there is some mechanism which keeps longer cracks from running away from shorter ones, or, equivalently, a mechanism for shorter cracks to catch-up with longer cracks. This basic mechanism has not been identified, and one of the objectives of the work is to see to what extent the mechanism is revealed by a fracture analysis of the MSD cracks. Another related aim is to present accurate stress intensity factor variations with crack length which can be used to estimate fatigue crack growth lifetimes once cracks have been initiated. Results are presented which illustrate the influence of load shedding from rivets with long cracks to neighboring rivets with shorter cracks. Results are also included

14 CFR 43.7 - Persons authorized to approve aircraft, airframes, aircraft engines, propellers, appliances, or...

Science.gov (United States)

2010-01-01

... data approved by the Administrator. (e) The holder of an air carrier operating certificate or an... holder of a repairman certificate (light-sport aircraft) with a maintenance rating may approve an aircraft issued a special airworthiness certificate in light-sport category for return to service, as...

Future aircraft networks and schedules

Science.gov (United States)

Shu, Yan

2011-07-01

Because of the importance of air transportation scheduling, the emergence of small aircraft and the vision of future fuel-efficient aircraft, this thesis has focused on the study of aircraft scheduling and network design involving multiple types of aircraft and flight services. It develops models and solution algorithms for the schedule design problem and analyzes the computational results. First, based on the current development of small aircraft and on-demand flight services, this thesis expands a business model for integrating on-demand flight services with the traditional scheduled flight services. This thesis proposes a three-step approach to the design of aircraft schedules and networks from scratch under the model. In the first step, both a frequency assignment model for scheduled flights that incorporates a passenger path choice model and a frequency assignment model for on-demand flights that incorporates a passenger mode choice model are created. In the second step, a rough fleet assignment model that determines a set of flight legs, each of which is assigned an aircraft type and a rough departure time is constructed. In the third step, a timetable model that determines an exact departure time for each flight leg is developed. Based on the models proposed in the three steps, this thesis creates schedule design instances that involve almost all the major airports and markets in the United States. The instances of the frequency assignment model created in this thesis are large-scale non-convex mixed-integer programming problems, and this dissertation develops an overall network structure and proposes iterative algorithms for solving these instances. The instances of both the rough fleet assignment model and the timetable model created in this thesis are large-scale mixed-integer programming problems, and this dissertation develops subproblem schemes for solving these instances. Based on these solution algorithms, this dissertation also presents

Review of Aircraft Electric Power Systems and Architectures

DEFF Research Database (Denmark)

Zhao, Xin; Guerrero, Josep M.; Wu, Xiaohao

2014-01-01

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....

A new simulation model for assessing aircraft emergency evacuation considering passenger physical characteristics

International Nuclear Information System (INIS)

Liu, Yu; Wang, Weijie; Huang, Hong-Zhong; Li, Yanfeng; Yang, Yuanjian

2014-01-01

Conducting a real aircraft evacuation trial is oftentimes unaffordable as it is extremely expensive and may cause severe injury to participants. Simulation models as an alternative have been used to overcome the aforementioned issues in recent years. This paper proposes a new simulation model for emergency evacuation of civil aircraft. Its unique features and advantages over the existing models are twofold: (1) passengers' critical physical characteristics, e.g. waist size, gender, age, and disabilities, which impact the movement and egress time of individual evacuee from a statistical viewpoint, are taken into account in the new model. (2) Improvements are made to enhance the accuracy of the simulation model from three aspects. First, the staggered mesh discretization method together with the agent-based approach is utilized to simulate movements of individual passengers in an emergency evacuation process. Second, each node discretized to represent cabin space in the new model can contain more than one passenger if they are moving in the same direction. Finally, each individual passenger is able to change his/her evacuation route in a real-time manner based upon the distance from the current position to the target exit and the queue length. The effectiveness of the proposed simulation model is demonstrated on Boeing 767-300 aircraft. - Highlights: • A new simulation model of aircraft emergency evacuation is developed. • Some critical physical characteristics of passengers', e.g. waist size, gender, age, and disabilities, are taken into account in the new model. • An agent-based approach along with a multi-level fine network representation is used. • Passengers are able to change their evacuation routes in a real-time manner based upon distance and length of queue

77 FR 45979 - Airworthiness Directives; Piper Aircraft, Inc. Airplanes

Science.gov (United States)

2012-08-02

... Airworthiness Directives; Piper Aircraft, Inc. Airplanes AGENCY: Federal Aviation Administration (FAA), DOT... (AD) for certain Piper Aircraft, Inc. (type certificate previously held by The New Piper Aircraft Inc... information identified in this proposed AD, contact Piper Aircraft, Inc., 2926 Piper Drive, Vero Beach...

Outcome of extremely low birth weight infants who received delivery room cardiopulmonary resuscitation.

Science.gov (United States)

Wyckoff, Myra H; Salhab, Walid A; Heyne, Roy J; Kendrick, Douglas E; Stoll, Barbara J; Laptook, Abbot R

2012-02-01

To determine whether delivery room cardiopulmonary resuscitation (DR-CPR) independently predicts morbidities and neurodevelopmental impairment (NDI) in extremely low birth weight infants. We conducted a cohort study of infants born with birth weight of 401 to 1000 g and gestational age of 23 to 30 weeks. DR-CPR was defined as chest compressions, medications, or both. Logistic regression was used to determine associations among DR-CPR and morbidities, mortality, and NDI at 18 to 24 months of age (Bayley II mental or psychomotor index blindness, or deafness). Data are adjusted ORs with 95% CIs. Of 8685 infants, 1333 (15%) received DR-CPR. Infants who received DR-CPR had lower birth weight (708±141 g versus 764±146g, PCPR had more pneumothoraces (OR, 1.28; 95% CI, 1.48-2.99), grade 3 to 4 intraventricular hemorrhage (OR, 1.47; 95% CI, 1.23-1.74), bronchopulmonary dysplasia (OR, 1.34; 95% CI, 1.13-1.59), death by 12 hours (OR, 3.69; 95% CI, 2.98-4.57), and death by 120 days after birth (OR, 2.22; 95% CI, 1.93-2.57). Rates of NDI in survivors (OR, 1.23; 95% CI, 1.02-1.49) and death or NDI (OR, 1.70; 95% CI, 1.46-1.99) were higher for DR-CPR infants. Only 14% of DR-CPR recipients with 5-minute Apgar score CPR is a prognostic marker for higher rates of mortality and NDI for extremely low birth weight infants. New DR-CPR strategies are needed for this population. Copyright © 2012 Mosby, Inc. All rights reserved.

Cosmic Radiation - An Aircraft Manufacturer's View

International Nuclear Information System (INIS)

Hume, C.

1999-01-01

The relevance and context of cosmic radiation to an aircraft maker Airbus Industrie are outlined. Some future developments in aircraft and air traffic are described, along with their possible consequences for exposure. (author)

2002 Industry Studies: Aircraft

Science.gov (United States)

2002-01-01

aircraft to a defense electronics, systems integration and information technology company.39 Northrop Grumman no longer seeks a position as a prime...between the military and civil market . Though also upgrading the H-1 helicopter series for the USMC, Bell has mortgaged its future on tiltrotor technology ...business in export dollars, the industry has been forced to look for new markets as worldwide aircraft sales have dropped. Because the U.S. national

Multifuel rotary aircraft engine

Science.gov (United States)

Jones, C.; Berkowitz, M.

1980-01-01

The broad objectives of this paper are the following: (1) to summarize the Curtiss-Wright design, development and field testing background in the area of rotary aircraft engines; (2) to briefly summarize past activity and update development work in the area of stratified charge rotary combustion engines; and (3) to discuss the development of a high-performance direct injected unthrottled stratified charge rotary combustion aircraft engine. Efficiency improvements through turbocharging are also discussed.

Final Rule for Control of Air Pollution From Aircraft and Aircraft Engines; Emission Standards and Test Procedures

Science.gov (United States)

EPA adopted emission standards and related provisions for aircraft gas turbine engines with rated thrusts greater than 26.7 kilonewtons. These engines are used primarily on commercial passenger and freight aircraft.

Development and experimental characterization of a fuel cell powered aircraft

Energy Technology Data Exchange (ETDEWEB)

Bradley, Thomas H.; Moffitt, Blake A.; Mavris, Dimitri N.; Parekh, David E. [Georgia Institute of Technology, Atlanta, GA 30332-0405 (United States)

2007-09-27

This paper describes the characteristics and performance of a fuel cell powered unmanned aircraft. The aircraft is novel as it is the largest compressed hydrogen fuel cell powered airplane built to date and is currently the only fuel cell aircraft whose design and test results are in the public domain. The aircraft features a 500 W polymer electrolyte membrane fuel cell with full balance of plant and compressed hydrogen storage incorporated into a custom airframe. Details regarding the design requirements, implementation and control of the aircraft are presented for each major aircraft system. The performances of the aircraft and powerplant are analyzed using data from flights and laboratory tests. The efficiency and component power consumption of the fuel cell propulsion system are measured at a variety of flight conditions. The performance of the aircraft powerplant is compared to other 0.5-1 kW-scale fuel cell powerplants in the literature and means of performance improvement for this aircraft are proposed. This work represents one of the first studies of fuel cell powered aircraft to result in a demonstration aircraft. As such, the results of this study are of practical interest to fuel cell powerplant and aircraft designers. (author)

77 FR 31169 - Airworthiness Directives; Piper Aircraft, Inc. Airplanes

Science.gov (United States)

2012-05-25

... Airworthiness Directives; Piper Aircraft, Inc. Airplanes AGENCY: Federal Aviation Administration (FAA), DOT... Piper Aircraft, Inc. (type certificate previously held by The New Piper Aircraft Inc.) Models PA-31T and..., contact Piper Aircraft, Inc., 926 Piper Drive, Vero Beach, Florida 32960; telephone: (772) 567-4361...

Challenges of future aircraft propulsion: A review of distributed propulsion technology and its potential application for the all electric commercial aircraft

Science.gov (United States)

Gohardani, Amir S.; Doulgeris, Georgios; Singh, Riti

2011-07-01

This paper highlights the role of distributed propulsion technology for future commercial aircraft. After an initial historical perspective on the conceptual aspects of distributed propulsion technology and a glimpse at numerous aircraft that have taken distributed propulsion technology to flight, the focal point of the review is shifted towards a potential role this technology may entail for future commercial aircraft. Technological limitations and challenges of this specific technology are also considered in combination with an all electric aircraft concept, as means of predicting the challenges associated with the design process of a next generation commercial aircraft.

36 CFR 331.14 - Aircraft.

Science.gov (United States)

2010-07-01

... GOVERNING THE PROTECTION, USE AND MANAGEMENT OF THE FALLS OF THE OHIO NATIONAL WILDLIFE CONSERVATION AREA, KENTUCKY AND INDIANA § 331.14 Aircraft. (a) The operation of aircraft on WCA lands and waters is prohibited... business of the Federal Government or used in emergency rescue in accordance with the directions of the...

ERGONOMIC DESIGN OF AIRCRAFT COCKPIT

Directory of Open Access Journals (Sweden)

CÎMPIAN Ionuţ

2012-09-01

Full Text Available This paper presents a model for an ergonomic design of an aircraft cockpit with the specification and verification with respect to the new European Aviation Safety Agency (EASA and Federal Aviation Administration (FAA requirements. The goal is to expressing the concepts on which the aircraft cockpit design are based.

ERGONOMIC DESIGN OF AIRCRAFT COCKPIT

Directory of Open Access Journals (Sweden)

CÎMPIAN Ionuţ

2011-06-01

Full Text Available This paper presents a model for an ergonomic design of an aircraft cockpit with the specification and verification with respect to the new European Aviation Safety Agency (EASA and Federal Aviation Administration (FAA requirements. The goal is to expressing the concepts on which the aircraft cockpit design is based.

Air-sampling inlet contamination by aircraft emissions on the NASA CV-990 aircraft

Science.gov (United States)

Condon, E. P.; Vedder, J. F.

1984-01-01

Results of an experimental investigation of the contamination of air sampling inlets by aircraft emissions from the NASA CV-990 research aircraft are presented. This four-engine jet aircraft is a NASA facility used for many different atmospheric and meteorological experiments, as well as for developing spacecraft instrumentation for remote measurements. Our investigations were performed to provide information on which to base the selection of sampling locations for a series of multi-instrument missions for measuring tropospheric trace gases. The major source of contamination is the exhaust from the jet engines, which generate many of the same gases that are of interest in atmospheric chemistry, as well as other gases that may interfere with sampling measurements. The engine exhaust contains these gases in mixing ratios many orders of magnitude greater than those that occur in the clean atmosphere which the missions seek to quantify. Pressurized samples of air were collected simultaneously from a scoop located forward of the engines to represent clean air and from other multiport scoops at various aft positions on the aircraft. The air samples were analyzed in the laboratory by gas chromatography for carbon monoxide, an abundant combustion by-product. Data are presented for various scoop locations under various flight conditions.

Modeling Programs Increase Aircraft Design Safety

Science.gov (United States)

2012-01-01

Flutter may sound like a benign word when associated with a flag in a breeze, a butterfly, or seaweed in an ocean current. When used in the context of aerodynamics, however, it describes a highly dangerous, potentially deadly condition. Consider the case of the Lockheed L-188 Electra Turboprop, an airliner that first took to the skies in 1957. Two years later, an Electra plummeted to the ground en route from Houston to Dallas. Within another year, a second Electra crashed. In both cases, all crew and passengers died. Lockheed engineers were at a loss as to why the planes wings were tearing off in midair. For an answer, the company turned to NASA s Transonic Dynamics Tunnel (TDT) at Langley Research Center. At the time, the newly renovated wind tunnel offered engineers the capability of testing aeroelastic qualities in aircraft flying at transonic speeds near or just below the speed of sound. (Aeroelasticity is the interaction between aerodynamic forces and the structural dynamics of an aircraft or other structure.) Through round-the-clock testing in the TDT, NASA and industry researchers discovered the cause: flutter. Flutter occurs when aerodynamic forces acting on a wing cause it to vibrate. As the aircraft moves faster, certain conditions can cause that vibration to multiply and feed off itself, building to greater amplitudes until the flutter causes severe damage or even the destruction of the aircraft. Flutter can impact other structures as well. Famous film footage of the Tacoma Narrows Bridge in Washington in 1940 shows the main span of the bridge collapsing after strong winds generated powerful flutter forces. In the Electra s case, faulty engine mounts allowed a type of flutter known as whirl flutter, generated by the spinning propellers, to transfer to the wings, causing them to vibrate violently enough to tear off. Thanks to the NASA testing, Lockheed was able to correct the Electra s design flaws that led to the flutter conditions and return the

Technology for reducing aircraft engine pollution

Science.gov (United States)

Rudey, R. A.; Kempke, E. E., Jr.

1975-01-01

Programs have been initiated by NASA to develop and demonstrate advanced technology for reducing aircraft gas turbine and piston engine pollutant emissions. These programs encompass engines currently in use for a wide variety of aircraft from widebody-jets to general aviation. Emission goals for these programs are consistent with the established EPA standards. Full-scale engine demonstrations of the most promising pollutant reduction techniques are planned within the next three years. Preliminary tests of advanced technology gas turbine engine combustors indicate that significant reductions in all major pollutant emissions should be attainable in present generation aircraft engines without adverse effects on fuel consumption. Fundamental-type programs are yielding results which indicate that future generation gas turbine aircraft engines may be able to utilize extremely low pollutant emission combustion systems.

Maintenance program developmentandImport /Export of Aircraft in USA

OpenAIRE

Takele, Teklu

2009-01-01

AbstractThis thesis discuss how United Parcel Service (UPS) develop its aircraft maintenanceprogram after import of McDonnell Douglas MD-11aircraft and the process of exporting newMD-11 aircraft from manufacturer in USA to European operator as passenger aircraft. It alsodiscusses the process of importing the same types of aircraft as freight carrier. The aircraftundergo, through different modifications at Singapore Technologies Aerospace (STA)conversion from passenger to freight carrier, a pr...

Defense Strategy of Aircraft Confronted with IR Guided Missile

Directory of Open Access Journals (Sweden)

Hesong Huang

2017-01-01

Full Text Available Surface-type infrared (IR decoy can simulate the IR characteristics of the target aircraft, which is one of the most effective equipment to confront IR guided missile. In the air combat, the IR guided missile poses a serious threat to the aircraft when it comes from the front of target aircraft. In this paper, firstly, the model of aircraft and surface-type IR decoy is established. To ensure their authenticity, the aircraft maneuver and radiation models based on real data of flight and exhaust system radiation in the state of different heights and different speeds are established. Secondly, the most effective avoidance maneuver is simulated when the missile comes from the front of the target aircraft. Lastly, combining maneuver with decoys, the best defense strategy is analysed when the missile comes from the front of aircraft. The result of simulation, which is authentic, is propitious to avoid the missile and improve the survivability of aircraft.

Live Aircraft Encounter Visualization at FutureFlight Central

Science.gov (United States)

Murphy, James R.; Chinn, Fay; Monheim, Spencer; Otto, Neil; Kato, Kenji; Archdeacon, John

2018-01-01

Researchers at the National Aeronautics and Space Administration (NASA) have developed an aircraft data streaming capability that can be used to visualize live aircraft in near real-time. During a joint Federal Aviation Administration (FAA)/NASA Airborne Collision Avoidance System flight series, test sorties between unmanned aircraft and manned intruder aircraft were shown in real-time at NASA Ames' FutureFlight Central tower facility as a virtual representation of the encounter. This capability leveraged existing live surveillance, video, and audio data streams distributed through a Live, Virtual, Constructive test environment, then depicted the encounter from the point of view of any aircraft in the system showing the proximity of the other aircraft. For the demonstration, position report data were sent to the ground from on-board sensors on the unmanned aircraft. The point of view can be change dynamically, allowing encounters from all angles to be observed. Visualizing the encounters in real-time provides a safe and effective method for observation of live flight testing and a strong alternative to travel to the remote test range.

FAA Fluorescent Penetrant Activities - An Update

Energy Technology Data Exchange (ETDEWEB)

Moore, D.G.

1998-10-20

The Federal Aviation Administration's Airworthiness Assurance NDI Validation Center (AANC) is currently characterizing low cycle fatigue specimens that will support the needs of penetrant manufacturers, commercial airline industry and the Federal Aviation Administration. The main focus of this characterization is to maintain and enhance the evaluation of penetrant inspection materials and apply resources to support the aircraft community needs. This paper discusses efforts to-date to document the Wright Laboratory penetrant evaluation process and characterize penetrant brightness readings in the initial set of sample calibration panels using Type 1 penetrant.

77 FR 70114 - Airworthiness Directives; Cessna Aircraft Company Airplanes

Science.gov (United States)

2012-11-23

... Aircraft Company Service Bulletin SB04-28-03, dated August 30, 2004, and Engine Fuel Return System... Aircraft System Component (JASC)/Air Transport Association (ATA) of America Code 2820, Aircraft Fuel... Modification Do not incorporate Cessna Aircraft Company Engine Fuel Return System Modification Kit MK 172-28-01...

V/STOL tilt rotor aircraft study. Volume 6: Preliminary design of a composite wing for tilt rotor research aircraft

Science.gov (United States)

Soule, V. A.; Badri-Nath, Y.

1973-01-01

The results of a study of the use of composite materials in the wing of a tilt rotor aircraft are presented. An all-metal tilt rotor aircraft was first defined to provide a basis for comparing composite with metal structure. A configuration study was then done in which the wing of the metal aircraft was replaced with composite wings of varying chord and thickness ratio. The results of this study defined the design and performance benefits obtainable with composite materials. Based on these results the aircraft was resized with a composite wing to extend the weight savings to other parts of the aircraft. A wing design was then selected for detailed structural analysis. A development plan including costs and schedules to develop this wing and incorporate it into a proposed flight research tilt rotor vehicle has been devised.

Scheduling Aircraft Landings under Constrained Position Shifting

Science.gov (United States)

Balakrishnan, Hamsa; Chandran, Bala

2006-01-01

Optimal scheduling of airport runway operations can play an important role in improving the safety and efficiency of the National Airspace System (NAS). Methods that compute the optimal landing sequence and landing times of aircraft must accommodate practical issues that affect the implementation of the schedule. One such practical consideration, known as Constrained Position Shifting (CPS), is the restriction that each aircraft must land within a pre-specified number of positions of its place in the First-Come-First-Served (FCFS) sequence. We consider the problem of scheduling landings of aircraft in a CPS environment in order to maximize runway throughput (minimize the completion time of the landing sequence), subject to operational constraints such as FAA-specified minimum inter-arrival spacing restrictions, precedence relationships among aircraft that arise either from airline preferences or air traffic control procedures that prevent overtaking, and time windows (representing possible control actions) during which each aircraft landing can occur. We present a Dynamic Programming-based approach that scales linearly in the number of aircraft, and describe our computational experience with a prototype implementation on realistic data for Denver International Airport.

AIRCRAFT MAINTENANCE HANGAR

Directory of Open Access Journals (Sweden)

GEAMBASU Gabriel George

2017-05-01

Full Text Available The paper presents the maintenance process that is done on an airplane, at a certain period of time, or after a number of flight hours or cycles and describes the checks performed behind each inspection. The first part of research describes the aircraft maintenance process that has to be done after an updated maintenance manual according with aircraft type, followed by a short introduction about maintenance hangar. The second part of the paper presents a hangar design with a foldable roof and walls, which can be folded or extended, over an airplane when a maintenance process is done, or depending on weather condition.

Airfoil optimization for morphing aircraft

Science.gov (United States)

Namgoong, Howoong

Continuous variation of the aircraft wing shape to improve aerodynamic performance over a wide range of flight conditions is one of the objectives of morphing aircraft design efforts. This is being pursued because of the development of new materials and actuation systems that might allow this shape change. The main purpose of this research is to establish appropriate problem formulations and optimization strategies to design an airfoil for morphing aircraft that include the energy required for shape change. A morphing aircraft can deform its wing shape, so the aircraft wing has different optimum shapes as the flight condition changes. The actuation energy needed for moving the airfoil surface is modeled and used as another design objective. Several multi-objective approaches are applied to a low-speed, incompressible flow problem and to a problem involving low-speed and transonic flow. The resulting solutions provide the best tradeoff between low drag, high energy and higher drag, low energy sets of airfoil shapes. From this range of solutions, design decisions can be made about how much energy is needed to achieve a desired aerodynamic performance. Additionally, an approach to model aerodynamic work, which would be more realistic and may allow using pressure on the airfoil to assist a morphing shape change, was formulated and used as part of the energy objective. These results suggest that it may be possible to design a morphing airfoil that exploits the airflow to reduce actuator energy.

76 FR 71081 - Public Aircraft Oversight Safety Forum

Science.gov (United States)

2011-11-16

... NATIONAL TRANSPORTATION SAFETY BOARD Public Aircraft Oversight Safety Forum The National Transportation Safety Board (NTSB) will convene a Public Aircraft Oversight Safety Forum which will begin at 9 a... ``Public Aircraft Oversight Forum: Ensuring Safety for Critical Missions'', are to (1) raise awareness of...

Transport aircraft loading and balancing system: Using a CLIPS expert system for military aircraft load planning

Science.gov (United States)

Richardson, J.; Labbe, M.; Belala, Y.; Leduc, Vincent

1994-01-01

The requirement for improving aircraft utilization and responsiveness in airlift operations has been recognized for quite some time by the Canadian Forces. To date, the utilization of scarce airlift resources has been planned mainly through the employment of manpower-intensive manual methods in combination with the expertise of highly qualified personnel. In this paper, we address the problem of facilitating the load planning process for military aircraft cargo planes through the development of a computer-based system. We introduce TALBAS (Transport Aircraft Loading and BAlancing System), a knowledge-based system designed to assist personnel involved in preparing valid load plans for the C130 Hercules aircraft. The main features of this system which are accessible through a convivial graphical user interface, consists of the automatic generation of valid cargo arrangements given a list of items to be transported, the user-definition of load plans and the automatic validation of such load plans.

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

Science.gov (United States)

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

2013-01-01

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

78 FR 7642 - Airworthiness Directives; Piper Aircraft, Inc.

Science.gov (United States)

2013-02-04

... Airworthiness Directives; Piper Aircraft, Inc. AGENCY: Federal Aviation Administration (FAA), DOT. ACTION: Final rule. SUMMARY: We are adopting a new airworthiness directive (AD) for certain Piper Aircraft, Inc. (type certificate previously held by The New Piper Aircraft Inc.) PA-28, PA-32, PA-34, and PA-44...

Fault Diagnosis and Fault Handling for Autonomous Aircraft

DEFF Research Database (Denmark)

Hansen, Søren

Unmanned Aerial vehicles (UAVs) or drones are used increasingly for missions where piloted aircraft are unsuitable. The unmanned aircraft has a number of advantages with respect to size, weight and manoeuvrability that makes it possible for them to solve tasks that an aircraft previously has been...

Aircraft Noise and Quality of Life around Frankfurt Airport

Directory of Open Access Journals (Sweden)

Thomas Eikmann

2010-08-01

Full Text Available In a survey of 2,312 residents living near Frankfurt Airport aircraft noise annoyance and disturbances as well as environmental (EQoL and health-related quality of life (HQoL were assessed and compared with data on exposure due to aircraft, road traffic, and railway noise. Results indicate higher noise annoyance than predicted from general exposure-response curves. Beside aircraft sound levels source-related attitudes were associated with reactions to aircraft noise. Furthermore, aircraft noise affected EQoL in general, although to a much smaller extent. HQoL was associated with aircraft noise annoyance, noise sensitivity and partly with aircraft noise exposure, in particular in the subgroup of multimorbid residents. The results suggest a recursive relationship between noise and health, yet this cannot be tested in cross-sectional studies. Longitudinal studies would be recommendable to get more insight in the causal paths underlying the noise-health relationship.

Hydrogen aircraft and airport safety

International Nuclear Information System (INIS)

Schmidtchen, U.; Behrend, E.; Pohl, H.-W.; Rostek, N.

1997-01-01

First flight tests with a hydrogen demonstrator aircraft, currently under investigation in the scope of the German-Russia Cryoplane project, are scheduled for 1999. Regular service with regional aircraft may begin around 2005, followed by larger Airbus-type airliners around 2010-2015. The fuel storage aboard such airliners will be of the order of 15 t or roughly 200 m 3 LH 2 . This paper investigates a number of safety problems associated with the handling and air transport of so much hydrogen. The same is done for the infrastructure on the airport. Major risks are identified, and appropriate measures in design and operation are recommended. It is found that hydrogen aircraft are no more dangerous than conventional ones - safer in some respects. (author)

Durability of aircraft composite materials

Science.gov (United States)

Dextern, H. B.

1982-01-01

Confidence in the long term durability of advanced composites is developed through a series of flight service programs. Service experience is obtained by installing secondary and primary composite components on commercial and military transport aircraft and helicopters. Included are spoilers, rudders, elevators, ailerons, fairings and wing boxes on transport aircraft and doors, fairings, tail rotors, vertical fins, and horizontal stabilizers on helicopters. Materials included in the evaluation are boron/epoxy, Kevlar/epoxy, graphite/epoxy and boron/aluminum. Inspection, maintenance, and repair results for the components in service are reported. The effects of long term exposure to laboratory, flight, and outdoor environmental conditions are reported for various composite materials. Included are effects of moisture absorption, ultraviolet radiation, and aircraft fuels and fluids.

Aircraft cybernetics

Science.gov (United States)

1977-01-01

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

AIRTV: Broadband Direct to Aircraft

Science.gov (United States)

Sorbello, R.; Stone, R.; Bennett, S. B.; Bertenyi, E.

2002-01-01

Airlines have been continuously upgrading their wide-body, long-haul aircraft with IFE (in-flight entertainment) systems that can support from 12 to 24 channels of video entertainment as well as provide the infrastructure to enable in-seat delivery of email and internet services. This is a direct consequence of increased passenger demands for improved in-flight services along with the expectations that broadband delivery systems capable of providing live entertainment (news, sports, financial information, etc.) and high speed data delivery will soon be available. The recent events of Sept. 11 have slowed the airline's upgrade of their IFE systems, but have also highlighted the compelling need for broadband aeronautical delivery systems to include operational and safety information. Despite the impact of these events, it is estimated that by 2005 more than 3000 long haul aircraft (servicing approximately 1 billion passengers annually) will be fully equipped with modern IFE systems. Current aircraft data delivery systems, which use either Inmarsat or NATS, are lacking in bandwidth and consequently are unsuitable to satisfy passenger demands for broadband email/internet services or the airlines' burgeoning data requirements. Present live video delivery services are limited to regional coverage and are not readily expandable to global or multiregional service. Faced with a compelling market demand for high data transport to aircraft, AirTV has been developing a broadband delivery system that will meet both passengers' and airlines' needs. AirTV is a global content delivery system designed to provide a range of video programming and data services to commercial airlines. When AirTV is operational in 2004, it will provide a broadband connection directly to the aircraft, delivering live video entertainment, internet/email service and essential operational and safety data. The system has been designed to provide seamless global service to all airline routes except for those

Cyclic hygrothermal aging of aircraft lightning protections: Phenomenological overview

KAUST Repository

Lubineau, Gilles

2012-04-23

The recent transition to full composite fuselages is a major breakthrough in aeronautical design. To ensure satisfactory lightning protection, the electrical properties of the primary composite structure need to be improved and a design solution lies on bonding a metallic fishnet to the fuselage. An important issue is the prediction of the aging behavior of this top layer when exposed to severe aging conditions representative of flight environment. Multiple aging mechanisms affect this top layer made of thermoset resin and metallic fishnet with complex geometry and a first modeling strategy is a necessary starting point to better understand its evolution. This paper describes the overall phenomenology and the different mechanisms that can be expected in such a structure.

Cyclic hygrothermal aging of aircraft lightning protections: Phenomenological overview

KAUST Repository

Lubineau, Gilles; El Yagoubi, Jalal; Saghir, Shahid; Selvakumaran, Lakshmi; Askari, Abe H.

2012-01-01

The recent transition to full composite fuselages is a major breakthrough in aeronautical design. To ensure satisfactory lightning protection, the electrical properties of the primary composite structure need to be improved and a design solution lies on bonding a metallic fishnet to the fuselage. An important issue is the prediction of the aging behavior of this top layer when exposed to severe aging conditions representative of flight environment. Multiple aging mechanisms affect this top layer made of thermoset resin and metallic fishnet with complex geometry and a first modeling strategy is a necessary starting point to better understand its evolution. This paper describes the overall phenomenology and the different mechanisms that can be expected in such a structure.

Knowledge-based scheduling of arrival aircraft

Science.gov (United States)

Krzeczowski, K.; Davis, T.; Erzberger, H.; Lev-Ram, I.; Bergh, C.

1995-01-01

A knowledge-based method for scheduling arrival aircraft in the terminal area has been implemented and tested in real-time simulation. The scheduling system automatically sequences, assigns landing times, and assigns runways to arrival aircraft by utilizing continuous updates of aircraft radar data and controller inputs. The scheduling algorithms is driven by a knowledge base which was obtained in over two thousand hours of controller-in-the-loop real-time simulation. The knowledge base contains a series of hierarchical 'rules' and decision logic that examines both performance criteria, such as delay reduction, as well as workload reduction criteria, such as conflict avoidance. The objective of the algorithms is to devise an efficient plan to land the aircraft in a manner acceptable to the air traffic controllers. This paper will describe the scheduling algorithms, give examples of their use, and present data regarding their potential benefits to the air traffic system.

Future V/STOL Aircraft For The Pacific Basin

Science.gov (United States)

Albers, James A.; Zuk, John

1992-01-01

Report describes geography and transportation needs of Asian Pacific region, and describes aircraft configurations suitable for region and compares performances. Examines applications of high-speed rotorcraft, vertical/short-takeoff-and-landing (V/STOL) aircraft, and short-takeoff-and landing (STOL) aircraft. Configurations benefit commerce, tourism, and development of resources.

31 CFR 538.519 - Aircraft and maritime safety.

Science.gov (United States)

2010-07-01

... 31 Money and Finance: Treasury 3 2010-07-01 2010-07-01 false Aircraft and maritime safety. 538.519..., Authorizations, and Statements of Licensing Policy § 538.519 Aircraft and maritime safety. Specific licenses may... aircraft, and to ensure the safety of ocean-going maritime traffic in international waters. ...

48 CFR 1852.228-71 - Aircraft flight risks.

Science.gov (United States)

2010-10-01

... 48 Federal Acquisition Regulations System 6 2010-10-01 2010-10-01 true Aircraft flight risks. 1852... 1852.228-71 Aircraft flight risks. (a) As prescribed in 1828.311-2, insert the following clause: Aircraft Flight Risks (DEC 1988) (a) Notwithstanding any other provision of this contract (particularly...

Conversion of the dual training aircraft (DC into single control advanced training aircraft (SC. Part I

Directory of Open Access Journals (Sweden)

Ioan ŞTEFĂNESCU

2011-03-01

Full Text Available Converting the DC school jet aircraft into SC advanced training aircraft - and use them forthe combat training of military pilots from the operational units, has become a necessity due to thebudget cuts for Air Force, with direct implications on reducing the number of hours of flight assignedto operating personnel for preparing and training.The purpose of adopting such a program is to reduce the number of flight hours allocated annuallyfor preparing and training in advanced stages of instruction, for every pilot, by more intensive use ofthis type of aircraft, which has the advantage of lower flight hour costs as compared to a supersoniccombat plane.

Alternative general-aircraft engines

Science.gov (United States)

Tomazic, W. A.

1976-01-01

The most promising alternative engine (or engines) for application to general aircraft in the post-1985 time period was defined, and the level of technology was cited to the point where confident development of a new engine can begin early in the 1980's. Low emissions, multifuel capability, and fuel economy were emphasized. Six alternative propulsion concepts were considered to be viable candidates for future general-aircraft application: the advanced spark-ignition piston, rotary combustion, two- and four-stroke diesel, Stirling, and gas turbine engines.

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

Science.gov (United States)

1972-01-01

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

Aircraft accident analysis for emergency planning and safety analysis

International Nuclear Information System (INIS)

Nicolosi, S.L.; Jordan, H.; Foti, D.; Mancuso, J.

1996-01-01

Potential aircraft accidents involving facilities at the Rocky Flats Environmental Technology Site (Site) are evaluated to assess their safety significance. This study addresses the probability and facility penetrability of aircraft accidents at the Site. The types of aircraft (large, small, etc.) that may credibly impact the Site determine the types of facilities that may be breached. The methodology used in this analysis follows elements of the draft Department of Energy Standard ''Accident Analysis for Aircraft Crash into Hazardous Facilities'' (July 1995). Key elements used are: the four-factor frequency equation for aircraft accidents; the distance criteria for consideration of airports, airways, and jet routes; the consideration of different types of aircraft; and the Modified National Defense Research Committee (NDRC) formula for projectile penetration, perforation, and minimum resistant thickness. The potential aircraft accident frequency for each type of aircraft applicable to the Site is estimated using a four-factor formula described in the draft Standard. The accident frequency is the product of the annual number of operations, probability of an accident, probability density function, and area. The annual number of operations is developed from site-specific and state-wide data

Aircraft engines. IV

Energy Technology Data Exchange (ETDEWEB)

Ruffles, P C

1989-01-01

Configurational design and thermodynamic performance gain trends are projected into the next 50 years, in view of the growing interest of aircraft manufacturers in both larger and more efficient high-bypass turbofan engines for subsonic flight and variable cycle engines for supersonic flight. Ceramic- and metal-matrix composites are envisioned as the key to achievement of turbine inlet temperatures 300 C higher than the 1400 C which is characteristic of the state-of-the-art, with the requisite high stiffness, strength, and low density. Such fiber-reinforced materials can be readily tailored to furnish greatest strength in a specific direction of loading. Large, low-density engines are critical elements of future 1000-seat aircraft.

Research on aircraft emissions. Need for future work

Energy Technology Data Exchange (ETDEWEB)

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

1998-12-31

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

Disruption Management for an Airline - Rescheduling of aircraft

DEFF Research Database (Denmark)

Larsen, Jesper; Løve, Michael; Sørensen, Kim Riis

2002-01-01

The Aircraft Recovery Problem (ARP) involves decisions concerning aircraft to flight assignments in situations where unforseen events have disrupted the existing flight schedule, e.g. bad weather causing flight delays. The aircraft recovery problem aims to recover these flight schedules through...... a series of reassignments of aircraft to flights, delaying of flights and cancellations of flights. This article demonstrates an effective method to solve ARP. A heuristic is implemented, which is able to generate feasible revised flight schedules of a good quality in less than 10 seconds. This article...

Research on aircraft emissions. Need for future work

Energy Technology Data Exchange (ETDEWEB)

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

1997-12-31

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

Commercial transport aircraft composite structures

Science.gov (United States)

Mccarty, J. E.

1983-01-01

The role that analysis plays in the development, production, and substantiation of aircraft structures is discussed. The types, elements, and applications of failure that are used and needed; the current application of analysis methods to commercial aircraft advanced composite structures, along with a projection of future needs; and some personal thoughts on analysis development goals and the elements of an approach to analysis development are discussed.

Neural networks for aircraft control

Science.gov (United States)

Linse, Dennis

1990-01-01

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

Aircraft Evaluation Using Stochastic Duels

Science.gov (United States)

2017-09-01

for Information Operations and Reports, 1215 Jefferson Davis Highway, Suite 1204, Arlington, VA 22202-4302, and to the Office of Management and...Fighter aircraft systems and weapons designs are known to involve substantial capital investment . Due to possible budget constraints in the U.S. Navy, the...of fighter aircraft to analysts and decision-makers before they invest further resources into larger-scale, higher-resolution simulations for

Pathfinder-Plus aircraft in flight

Science.gov (United States)

1998-01-01

The Pathfinder-Plus solar-powered aircraft is shown taking off from a runway, then flying at low altitude over the ocean. The vehicle, which looks like a flying ruler, operates at low airspeed. Among the missions proposed for a solar-powered aircraft are communications relay, atmospheric studies, pipeline monitoring and gas leak detection, environmental monitoring using thermal and radar images, and disaster relief and monitoring.

NASA Johnson Space Center Aircraft Operations Division

Science.gov (United States)

Bakalyar, John A.

2018-01-01

This presentation provides a high-level overview of JSC aircraft and missions. The capabilities, including previous missions and support team, for the Super Guppy Transport (SGT) aircraft are highlighted.

Versatile Electric Propulsion Aircraft Testbed, Phase I

Data.gov (United States)

National Aeronautics and Space Administration — An all-electric aircraft testbed is proposed to provide a dedicated development environment for the rigorous study and advancement of electrically powered aircraft....

Investigating accidents involving aircraft manufactured from polymer composite materials

OpenAIRE

Dunn, Leigh

2013-01-01

This thesis looks into the examination of polymer composite wreckage from the perspective of the aircraft accident investigator. It develops an understanding of the process of wreckage examination as well as identifying the potential for visual and macroscopic interpretation of polymer composite aircraft wreckage. The in-field examination of aircraft wreckage, and subsequent interpretations of material failures, can be a significant part of an aircraft accident investigation. ...

Frequency Analysis of Aircraft hazards for License Application

International Nuclear Information System (INIS)

K. Ashley

2006-01-01

The preclosure safety analysis for the monitored geologic repository at Yucca Mountain must consider the hazard that aircraft may pose to surface structures. Relevant surface structures are located beneath the restricted airspace of the Nevada Test Site (NTS) on the eastern slope of Yucca Mountain, near the North Portal of the Exploratory Studies Facility Tunnel (Figure 1). The North Portal is located several miles from the Nevada Test and Training Range (NTTR), which is used extensively by the U.S. Air Force (USAF) for training and test flights (Figure 1). The NTS airspace, which is controlled by the U.S. Department of Energy (DOE) for NTS activities, is not part of the NTTR. Agreements with the DOE allow USAF aircraft specific use of the airspace above the NTS (Reference 2.1.1 [DIRS 103472], Section 3.1.1 and Appendix A, Section 2.1; and Reference 2.1.2 [DIRS 157987], Sections 1.26 through 1.29). Commercial, military, and general aviation aircraft fly within several miles to the southwest of the repository site in the Beatty Corridor, which is a broad air corridor that runs approximately parallel to U.S. Highway 95 and the Nevada-California border (Figure 2). These aircraft and other aircraft operations are identified and described in ''Identification of Aircraft Hazards'' (Reference 2.1.3, Sections 6 and 8). The purpose of this analysis is to estimate crash frequencies for aircraft hazards identified for detailed analysis in ''Identification of Aircraft Hazards'' (Reference 2.1.3, Section 8). Reference 2.1.3, Section 8, also identifies a potential hazard associated with electronic jamming, which will be addressed in this analysis. This analysis will address only the repository and not the transportation routes to the site. The analysis is intended to provide the basis for: (1) Categorizing event sequences related to aircraft hazards; (2) Identifying design or operational requirements related to aircraft hazards

Frequency Analysis of Aircraft hazards for License Application

Energy Technology Data Exchange (ETDEWEB)

K. Ashley

2006-10-24

The preclosure safety analysis for the monitored geologic repository at Yucca Mountain must consider the hazard that aircraft may pose to surface structures. Relevant surface structures are located beneath the restricted airspace of the Nevada Test Site (NTS) on the eastern slope of Yucca Mountain, near the North Portal of the Exploratory Studies Facility Tunnel (Figure 1). The North Portal is located several miles from the Nevada Test and Training Range (NTTR), which is used extensively by the U.S. Air Force (USAF) for training and test flights (Figure 1). The NTS airspace, which is controlled by the U.S. Department of Energy (DOE) for NTS activities, is not part of the NTTR. Agreements with the DOE allow USAF aircraft specific use of the airspace above the NTS (Reference 2.1.1 [DIRS 103472], Section 3.1.1 and Appendix A, Section 2.1; and Reference 2.1.2 [DIRS 157987], Sections 1.26 through 1.29). Commercial, military, and general aviation aircraft fly within several miles to the southwest of the repository site in the Beatty Corridor, which is a broad air corridor that runs approximately parallel to U.S. Highway 95 and the Nevada-California border (Figure 2). These aircraft and other aircraft operations are identified and described in ''Identification of Aircraft Hazards'' (Reference 2.1.3, Sections 6 and 8). The purpose of this analysis is to estimate crash frequencies for aircraft hazards identified for detailed analysis in ''Identification of Aircraft Hazards'' (Reference 2.1.3, Section 8). Reference 2.1.3, Section 8, also identifies a potential hazard associated with electronic jamming, which will be addressed in this analysis. This analysis will address only the repository and not the transportation routes to the site. The analysis is intended to provide the basis for: (1) Categorizing event sequences related to aircraft hazards; (2) Identifying design or operational requirements related to aircraft hazards.

Risk Management of an Aging KC-130 Fleet

National Research Council Canada - National Science Library

Hoffman, Paul

1999-01-01

.... For the aging USMC KC-130 F/R fleet, a damage-tolerant approach ensured that safety would be maintained but it presented a problem in forecasting readiness, aircraft remaining in the inventory...

Aircraft crash upon outer containment of nuclear power plant

International Nuclear Information System (INIS)

Abbas, H.; Paul, D.K.; Godbole, P.N.; Nayak, G.C.

1996-01-01

In this paper, analysis of an aircraft crash upon an outer containment of a nuclear power plant is presented. The effect of target yielding is considered simultaneously by calculating the reaction time in a time marching scheme. The concrete model employed is capable of predicting the cracking and yielding. The response for different cracking strains and different locations of aircraft strike for different aircraft has been studied. Critical location of aircraft strike for the containment has been investigated. The analytical procedure and the material model used are found to be capable of representing the aircraft impact response of the containment structure. (orig.)

Turboelectric Aircraft Drive Key Performance Parameters and Functional Requirements

Science.gov (United States)

Jansen, Ralph H.; Brown, Gerald V.; Felder, James L.; Duffy, Kirsten P.

2016-01-01

The purpose of this paper is to propose specific power and efficiency as the key performance parameters for a turboelectric aircraft power system and investigate their impact on the overall aircraft. Key functional requirements are identified that impact the power system design. Breguet range equations for a base aircraft and a turboelectric aircraft are found. The benefits and costs that may result from the turboelectric system are enumerated. A break-even analysis is conducted to find the minimum allowable electric drive specific power and efficiency that can preserve the range, initial weight, operating empty weight, and payload weight of the base aircraft.

Safety of Cargo Aircraft Handling Procedure

Directory of Open Access Journals (Sweden)

Daniel Hlavatý

2017-07-01

Full Text Available The aim of this paper is to get acquainted with the ways how to improve the safety management system during cargo aircraft handling. The first chapter is dedicated to general information about air cargo transportation. This includes the history or types of cargo aircraft handling, but also the means of handling. The second part is focused on detailed description of cargo aircraft handling, including a description of activities that are performed before and after handling. The following part of this paper covers a theoretical interpretation of safety, safety indicators and legislative provisions related to the safety of cargo aircraft handling. The fourth part of this paper analyzes the fault trees of events which might occur during handling. The factors found by this analysis are compared with safety reports of FedEx. Based on the comparison, there is a proposal on how to improve the safety management in this transportation company.

Design definition study of a lift/cruise fan technology V/STOL aircraft. Volume 2: Technology aircraft

Science.gov (United States)

1975-01-01

Technology flight vehicles were defined for three different approaches which demonstrate the concept and characteristics of the multipurpose aircraft established for Navy missions. The propulsion system used for the various technology flight vehicles was representative of that established for the multipurpose aircraft. Existing J97-GE100 gas generators were selected based on cost, availability and exhaust characteristics. The LF459 fans were also selected and are compatible with both technology and operational vehicles. To comply with the design guideline safety criteria, it was determined that three gas generators were required to provide engine out safety in the hover flight mode. The final propulsion system established for the technology aircraft was three existing J97 gas generators powering three LF459 fans. Different aircraft candidates were evaluated for application to the three designated design approaches. Each configuration was evaluated on the basis of (1) propulsion system integration, (2) modification required, (3) pilot's visibility, (4) payload volume, and (5) adaptability to compatible location of center-of-gravity/aerodynamic center and thrust center.

14 CFR 121.538 - Aircraft security.

Science.gov (United States)

2010-01-01

... 14 Aeronautics and Space 3 2010-01-01 2010-01-01 false Aircraft security. 121.538 Section 121.538..., FLAG, AND SUPPLEMENTAL OPERATIONS Flight Operations § 121.538 Aircraft security. Certificate holders conducting operations under this part must comply with the applicable security requirements in 49 CFR chapter...

14 CFR 135.125 - Aircraft security.

Science.gov (United States)

2010-01-01

... 14 Aeronautics and Space 3 2010-01-01 2010-01-01 false Aircraft security. 135.125 Section 135.125....125 Aircraft security. Certificate holders conducting operators conducting operations under this part must comply with the applicable security requirements in 49 CFR chapter XII. [67 FR 8350, Feb. 22, 2002] ...

The influence of ozone on self-evaluation of symptoms in a simulated aircraft cabin

DEFF Research Database (Denmark)

Strøm-Tejsen, Peter; Weschler, Charles J.; Wargocki, Pawel

2008-01-01

Simulated 4-h flights were carried out in a realistic model of a three-row, 21-seat section of an aircraft cabin that was reconstructed inside a climate chamber. Twenty-nine female subjects, age 19-27 years, were split into two groups; each group was exposed to four conditions: two levels of ozone (...

Advanced technology composite aircraft structures

Science.gov (United States)

Ilcewicz, Larry B.; Walker, Thomas H.

1991-01-01

Work performed during the 25th month on NAS1-18889, Advanced Technology Composite Aircraft Structures, is summarized. The main objective of this program is to develop an integrated technology and demonstrate a confidence level that permits the cost- and weight-effective use of advanced composite materials in primary structures of future aircraft with the emphasis on pressurized fuselages. The period from 1-31 May 1991 is covered.

Small Aircraft Transportation System Higher Volume Operations Concept

Science.gov (United States)

Abbott, Terence S.; Consiglio, Maria C.; Baxley, Brian T.; Williams, Daniel M.; Jones, Kenneth M.; Adams, Catherine A.

2006-01-01

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.

Energy Conversion and Storage Requirements for Hybrid Electric Aircraft

Science.gov (United States)

Misra, Ajay

2016-01-01

Among various options for reducing greenhouse gases in future large commercial aircraft, hybrid electric option holds significant promise. In the hybrid electric aircraft concept, gas turbine engine is used in combination with an energy storage system to drive the fan that propels the aircraft, with gas turbine engine being used for certain segments of the flight cycle and energy storage system being used for other segments. The paper will provide an overview of various energy conversion and storage options for hybrid electric aircraft. Such options may include fuel cells, batteries, super capacitors, multifunctional structures with energy storage capability, thermoelectric, thermionic or a combination of any of these options. The energy conversion and storage requirements for hybrid electric aircraft will be presented. The role of materials in energy conversion and storage systems for hybrid electric aircraft will be discussed.

Offsite radiological consequence analysis for the bounding aircraft crash accident

International Nuclear Information System (INIS)

OBERG, B.D.

2003-01-01

The purpose of this calculation note is to quantitatively analyze a bounding aircraft crash accident for comparison to the DOE-STD-3009-94, ''Preparation Guide for U.S. Department of Energy Nonreactor Nuclear Facility Documented Safety Analyses'', Appendix A, Evaluation Guideline of 25 rem. The potential of aircraft impacting a facility was evaluated using the approach given in DOE-STD-3014-96, ''Accident Analysis for Aircraft Crash into Hazardous Facilities''. The following aircraft crash FR-equencies were determined for the Tank Farms in RPP-11736, ''Assessment Of Aircraft Crash FR-equency For The Hanford Site 200 Area Tank Farms'': (1) The total aircraft crash FR-equency is ''extremely unlikely.'' (2) The general aviation crash FR-equency is ''extremely unlikely.'' (3) The helicopter crash FR-equency is ''beyond extremely unlikely.'' (4) For the Hanford Site 200 Areas, other aircraft type, commercial or military, each above ground facility, and any other type of underground facility is ''beyond extremely unlikely.'' As the potential of aircraft crash into the 200 Area tank farms is more FR-equent than ''beyond extremely unlikely,'' consequence analysis of the aircraft crash is required

77 FR 41889 - Airworthiness Directives; Sikorsky Aircraft Corporation Helicopters

Science.gov (United States)

2012-07-17

... Airworthiness Directives; Sikorsky Aircraft Corporation Helicopters AGENCY: Federal Aviation Administration (FAA... airworthiness directive (AD) for Sikorsky Aircraft Corporation (Sikorsky) Model S-92A helicopters. This AD... identified in this AD, contact Sikorsky Aircraft Corporation, Attn: Manager, Commercial Technical Support...

77 FR 49710 - Airworthiness Directives; Sikorsky Aircraft Corporation Helicopters

Science.gov (United States)

2012-08-17

... Airworthiness Directives; Sikorsky Aircraft Corporation Helicopters AGENCY: Federal Aviation Administration (FAA... Aircraft Corporation (Sikorsky) Model S-76A helicopters to require modifying the electric rotor brake (ERB... service information identified in this AD, contact Sikorsky Aircraft Corporation, Attn: Manager...

Thermal comfort assessment in civil aircraft cabins

OpenAIRE

Pang Liping; Qin Yue; Liu Dong; Liu Meng

2014-01-01

Aircraft passengers are more and demanding in terms of thermal comfort. But it is not yet easy for aircraft crew to control the environment control system (ECS) that satisfies the thermal comfort for most passengers due to a number of causes. This paper adopts a corrected predicted mean vote (PMV) model and an adaptive model to assess the thermal comfort conditions for 31 investigated flights and draws the conclusion that there does exist an uncomfortable thermal phenomenon in civil aircraft ...

Aircraft Depainting Technology

National Research Council Canada - National Science Library

Kozol, Joseph

1999-01-01

... of aircraft and component stripping at various levels of maintenance. Under this program, the Navy pursued development of non-HAP chemical paint strippers as alternatives for methylene chloride based strippers...

New entrants and overcapacity: lessons from regional aircraft manufacturing

NARCIS (Netherlands)

Steenhuis, H.J.; de Bruijn, E.J.; Heerkens, Johannes M.G.

2010-01-01

The commercial aircraft manufacturing industry has been largely dominated by the advanced economies in North America and Western Europe. During recent decades, several emerging economies have invested heavily in the commercial aircraft industry, notably in regional aircraft manufacturing. This paper

78 FR 60656 - Airworthiness Directives; Sikorsky Aircraft Corporation Helicopters

Science.gov (United States)

2013-10-02

... Airworthiness Directives; Sikorsky Aircraft Corporation Helicopters AGENCY: Federal Aviation Administration (FAA... Aircraft Corporation (Sikorsky) Model S-92A helicopters to require modifying the No. 1 engine forward... Sikorsky Aircraft Corporation, Attn: Manager, Commercial Technical Support, mailstop s581a, 6900 Main...

77 FR 23382 - Airworthiness Directives; Sikorsky Aircraft Corporation Helicopters

Science.gov (United States)

2012-04-19

... Airworthiness Directives; Sikorsky Aircraft Corporation Helicopters AGENCY: Federal Aviation Administration (FAA... Aircraft Corporation (Sikorsky) Model S-92A helicopters. This AD was prompted by the manufacturer's..., contact Sikorsky Aircraft Corporation, Attn: Manager, Commercial Technical Support, Mailstop s581a, 6900...

77 FR 21402 - Airworthiness Directives; Sikorsky Aircraft Corporation Helicopters

Science.gov (United States)

2012-04-10

... Airworthiness Directives; Sikorsky Aircraft Corporation Helicopters AGENCY: Federal Aviation Administration (FAA... Aircraft Corporation (Sikorsky) Model S-92A helicopters. This AD was prompted by the discovery of tail... identified in this AD, contact Sikorsky Aircraft Corporation, Attn: Manager, Commercial Technical Support...

Nuclear Division Index may Predict Neoplastic Colorectal Lesions.

Science.gov (United States)

Ionescu, Mirela E; Ciocirlan, Mihai; Becheanu, Gabriel; Nicolaie, Tudor; Ditescu, Cristina; Teiusanu, Adriana G; Gologan, Serban I; Arbanas, Tudor; Diculescu, Mircea M

2011-07-01

Colorectal cancer (CRC) develops by accumulation of multiple genetic damages leading to genetic instability that can be evaluated by cytogenetic methods. In the current study we used Cytokinesis-Blocked Micronucleus Assay (CBMN) technique to assess the behavior of Nuclear Division Index(NDI) in peripheral lymphocytes of patients with CRC and polyps versus patients with normal colonoscopy. Blood samples were collected from patients after informed consent. By CBMN technique we assessed the proportion of mono-nucleated, bi-nucleated, tri-nucleated and tetra-nucleated cells/500 cells, to calculate NDI. Data were statistically analyzed using the SPSS 11.0 package. 45 patients were available for analysis, 23 men and 22 women, with a mean age of 58.7±13.5. 17 had normal colonoscopy, 17 colonic polyps and 11 CRC. The mean NDI values were significantly smaller for patients with CRC or polyps than in patients with normal colonoscopy (1.57 vs 1.73, p=0.013). The difference persisted for patients with neoplastic lesions (adenomas and carcinomas) when compared with patients with normal colonoscopy or non neoplastic (hyperplastic) polyps (1.56 vs.1.71, p=0.018). The NDI cut-off value to predict the presence of adenomas or carcinomas was equal to 1.55 with a 54.2% sensitivity and 81% specificity of lower values (p=0.019). The NDI cut off value to predict the presence of advanced adenomas or cancer was 1.525 for a sensitivity of 56.3% and a specificity of 82.8% (p=0.048). NDI may be useful in screening strategies for colorectal cancer as simple, noninvasive, inexpensive cytogenetic biomarker.

Beryllium in aircraft brakes - a summary

International Nuclear Information System (INIS)

Zenczak, S.

1977-01-01

Beryllium has been in use in aircraft brakes for ten years. During the original design phases of the several aircraft programs using beryllium a number of problems requiring solution confronted the designers. In actual service the solution to these problems performed much better than had been anticipated. A summary is presented. (author)

The Aircraft Industry

National Research Council Canada - National Science Library

Fitzgerald, Tim; Baiche, Noureddine; Brewer, Mike; Collins, Al; Knapp, Kathy; Kott, Marilyn; McGill, Duncan; Mensah, Dunstan; Neighbors, Mark; Reardon, Dee

2005-01-01

.... As the airline companies prepare to buy new Boeing and Airbus passenger jets, they remain under intense pressure to cut costs in order to remain profitable, forcing aircraft and engine manufacturers...

Modeling Aircraft Emissions for Regional-scale Air Quality: Adapting a New Global Aircraft Emissions Database for the U.S

Science.gov (United States)

Arunachalam, S.; Baek, B. H.; Vennam, P. L.; Woody, M. C.; Omary, M.; Binkowski, F.; Fleming, G.

2012-12-01

Commercial aircraft emit substantial amounts of pollutants during their complete activity cycle that ranges from landing-and-takeoff (LTO) at airports to cruising in upper elevations of the atmosphere, and affect both air quality and climate. Since these emissions are not uniformly emitted over the earth, and have substantial temporal and spatial variability, it is vital to accurately evaluate and quantify the relative impacts of aviation emissions on ambient air quality. Regional-scale air quality modeling applications do not routinely include these aircraft emissions from all cycles. Federal Aviation Administration (FAA) has developed the Aviation Environmental Design Tool (AEDT), a software system that dynamically models aircraft performance in space and time to calculate fuel burn and emissions from gate-to-gate for all commercial aviation activity from all airports globally. To process in-flight aircraft emissions and to provide a realistic representation of these for treatment in grid-based air quality models, we have developed an interface processor called AEDTproc that accurately distributes full-flight chorded emissions in time and space to create gridded, hourly model-ready emissions input data. Unlike the traditional emissions modeling approach of treating aviation emissions as ground-level sources or processing emissions only from the LTO cycles in regional-scale air quality studies, AEDTproc distributes chorded inventories of aircraft emissions during LTO cycles and cruise activities into a time-variant 3-D gridded structure. We will present results of processed 2006 global emissions from AEDT over a continental U.S. modeling domain to support a national-scale air quality assessment of the incremental impacts of aircraft emissions on surface air quality. This includes about 13.6 million flights within the U.S. out of 31.2 million flights globally. We will focus on assessing spatio-temporal variability of these commercial aircraft emissions, and

Civil aircraft side-facing seat research summary.

Science.gov (United States)

2012-11-01

The Federal Aviation Administration (FAA) has standards and regulations that are intended to protect aircraft : occupants in the event of a crash. However, side-facing seats were not specifically addressed when aircraft seat : dynamic test standards ...

Aircraft Icing Weather Data Reporting and Dissemination System

Science.gov (United States)

Bass, Ellen J.; Minsk, Brian; Lindholm, Tenny; Politovich, Marcia; Reehorst, Andrew (Technical Monitor)

2002-01-01

The long-term operational concept of this research is to develop an onboard aircraft system that assesses and reports atmospheric icing conditions automatically and in a timely manner in order to improve aviation safety and the efficiency of aircraft operations via improved real-time and forecast weather products. The idea is to use current measurement capabilities on aircraft equipped with icing sensors and in-flight data communication technologies as a reporting source. Without requiring expensive avionics upgrades, aircraft data must be processed and available for downlink. Ideally, the data from multiple aircraft can then be integrated (along with other real-time and modeled data) on the ground such that aviation-centered icing hazard metrics for volumes of airspace can be assessed. As the effect of icing on different aircraft types can vary, the information should be displayed in meaningful ways such that multiple types of users can understand the information. That is, information must be presented in a manner to allow users to understand the icing conditions with respect to individual concerns and aircraft capabilities. This research provides progress toward this operational concept by: identifying an aircraft platform capable of digitally capturing, processing, and downlinking icing data; identifying the required in situ icing data processing; investigating the requirements for routing the icing data for use by weather products; developing an icing case study in order to gain insight into major air carrier needs; developing and prototyping icing display concepts based on the National Center for Atmospheric Research's existing diagnostic and forecast experimental icing products; and conducting a usability study for the prototyped icing display concepts.

A fuselage/tank structure study for actively cooled hypersonic cruise vehicles, summary. [aircraft design of aircraft fuel systems

Science.gov (United States)

Pirrello, C. J.; Baker, A. H.; Stone, J. E.

1976-01-01

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.

Micro- and nano-NDE systems for aircraft: great things in small packages

Science.gov (United States)

Malas, James C.; Kropas-Hughes, Claudia V.; Blackshire, James L.; Moran, Thomas; Peeler, Deborah; Frazier, W. G.; Parker, Danny

2003-07-01

Recent advancements in small, microscopic NDE sensor technologies will revolutionize how aircraft maintenance is done, and will significantly improve the reliability and airworthiness of current and future aircraft systems. A variety of micro/nano systems and concepts are being developed that will enable whole new capabilities for detecting and tracking structural integrity damage. For aging aircraft systems, the impact of micro-NDE sensor technologies will be felt immediately, with dramatic reductions in labor for maintenance, and extended useable life of critical components being two of the primary benefits. For the fleet management of future aircraft systems, a comprehensive evaluation and tracking of vehicle health throughout its entire life cycle will be needed. Indeed, micro/nano NDE systems will be instrumental in realizing this futuristic vision. Several major challenges will need to be addressed, however, before micro- and nano-NDE systems can effectively be implemented, and this will require interdisciplinary research approaches, and a systematic engineering integration of the new technologies into real systems. Future research will need to emphasize systems engineering approaches for designing materials and structures with in-situ inspection and prognostic capabilities. Recent advances in 1) embedded / add-on micro-sensors, 2) computer modeling of nondestructive evaluation responses, and 3) wireless communications are important steps toward this goal, and will ultimately provide previously unimagined opportunities for realizing whole new integrated vehicle health monitoring capabilities. The future use of micro/nano NDE technologies as vehicle health monitoring tools will have profound implications, and will provide a revolutionary way of doing NDE in the near and distant future.

Information note about the protection of nuclear facilities against aircraft crashes

International Nuclear Information System (INIS)

2001-01-01

The protection of nuclear facilities against external risks (earthquakes, floods, fires etc..) is an aspect of safety taken into consideration by the French authority of nuclear safety (ASN). Concerning the aircraft crashes, the fundamental safety rules make three categories of aircraft: the small civil aircraft (weight 5.7 t). Nuclear facilities are designed to resist against crashes of aircraft from the first category only, because the probability of the accidental crash of a big aircraft are extremely low. This document comprises an information note about the protection of nuclear facilities against aircraft crashes, a dossier about the safety of nuclear facilities with respect to external risks in general (natural disasters and aircraft crashes), and an article about the protection of nuclear power plants against aircraft crashes (design, safety measures, regulation, surveillance, experience feedback). (J.S.)

Application of automation for low cost aircraft cabin simulator

NARCIS (Netherlands)

Tan, C.F.; Chen, W.; Boomen, van den G.J.A.; Rauterberg, G.W.M.

2010-01-01

This paper presents an application of automation for low cost aircraft cabin simulator. The aircraft cabin simulator is a testbed that was designed for research on aircraft passenger comfort mprovement product. The simulator consists of an economy class section, a business class section, a lavatory

77 FR 68058 - Airworthiness Directives; Sikorsky Aircraft Corporation Helicopters

Science.gov (United States)

2012-11-15

... Airworthiness Directives; Sikorsky Aircraft Corporation Helicopters AGENCY: Federal Aviation Administration (FAA... airworthiness directive (AD) for Sikorsky Aircraft Corporation (Sikorsky) Model S-70, S-70A, S-70C, S-70C(M... after receipt. For service information identified in this AD, contact Sikorsky Aircraft Corporation...

Aircraft Landing and Attitude Control Using Dynamic Matrix Control

Directory of Open Access Journals (Sweden)

George Cristian Calugaru

2017-06-01

Full Text Available This paper proposes a method for an efficient control of the aircraft landing and attitude through Dynamic Matrix Control. The idea of MPC structures used in aircraft control has been well established during the last few years, but some aspects require further investigation. With this in mind, the paper proposes structures for aircraft landing and aircraft attitude control by using single DMC controllers for landing and respectively one DMC controller for each of the attitude axis (pitch attitude hold, bank angle hold and heading hold. The model used for analysis of the aircraft landing structure is based on the last phase of landing. Also, the model used to illustrate the attitude control is that of a pitch attitude hold system of a N250-100 aircraft. Simulations are performed for a variety of control and prediction horizons, taking into account the possibility of adding a weighting factor for the control actions. Apart from separate studies on step reference variations, for some use cases, a generic reference trajectory is provided as a control purpose of the system. Results show a better performance of the proposed method in terms of control surface transition and protection of the actuators involved and a better time response in stabilizing the aircraft attitude. Overall, the aspects shown ensure an improved aircraft attitude control and landing stabilization.

Factors associated with pilot fatality in work-related aircraft crashes, Alaska, 1990-1999.

Science.gov (United States)

Bensyl, D M; Moran, K; Conway, G A

2001-12-01

Work-related aircraft crashes are the leading cause of occupational fatality in Alaska, with civilian pilots having the highest fatality rate (410/100,000/year). To identify factors affecting survivability, the authors examined work-related aircraft crashes that occurred in Alaska in the 1990s (1990-1999), comparing crashes with pilot fatalities to crashes in which the pilot survived. Using data from National Transportation Safety Board reports, the authors carried out logistic regression analysis with the following variables: age, flight experience, use of a shoulder restraint, weather conditions (visual flight vs. instrument flight), light conditions (daylight vs. darkness), type of aircraft (airplane vs. helicopter), postcrash fire, crash location (airport vs. elsewhere), and state of residence. In the main-effects model, significant associations were found between fatality and postcrash fire (adjusted odds ratio (AOR) = 6.43, 95% confidence interval (CI): 2.38, 17.37), poor weather (AOR = 4.11, 95% CI: 2.15, 7.87), and non-Alaska resident status (AOR = 2.10, 95% CI: 1.05, 4.20). Protective effects were seen for shoulder restraint use (AOR = 0.40, 95% CI: 0.21, 0.77) and daylight versus darkness (AOR = 0.50, 95% CI: 0.25, 0.99). The finding that state of residence was associated with survivability offers new information on pilot survivability in work-related aircraft crashes in Alaska. These results may be useful in targeting safety interventions for pilots who fly occupationally in Alaska or in similar environments.

Atmospheric/climatic effects of aircraft emissions

International Nuclear Information System (INIS)

Pueschel, R.F.

1996-01-01

Exhaust emissions from aircraft include oxides of nitrogen (NO x ), water vapor (H 2 O), sulfur dioxide (SO 2 ), carbon dioxide (CO 2 ), carbon monoxide (CO), hydrocarbons (HC) and particles (soot and sulfates). These emissions are small compared to industrial/urban surface emissions. However, because (1) atmospheric residence times of exhaust constituents are longer at altitude, particularly in the stratosphere, than they are in the boundary layer, (2) their background concentrations at altitude are lower than those near the surface, (3) the radiation balance is the more sensitive to atmospheric trace constituents the colder the temperature aloft and (4) inter-hemispheric mixing of aircraft effluents is inhibited, aircraft emissions near and above the tropopause and polewards of 40 degrees latitude can be environmentally critical. That's why atmospheric/climatic effects of aircraft emissions have again received scientific, economic and political scrutiny in the last few years, motivated by growth of subsonic traffic at about 5% per year over the past two decades and the advent of a technologically feasible operation of a supersonic high speed commercial transport (HSCT) fleet

Aircraft Fuel Cell Power Systems

Science.gov (United States)

Needham, Robert

2004-01-01

In recent years, fuel cells have been explored for use in aircraft. While the weight and size of fuel cells allows only the smallest of aircraft to use fuel cells for their primary engines, fuel cells have showed promise for use as auxiliary power units (APUs), which power aircraft accessories and serve as an electrical backup in case of an engine failure. Fuel cell MUS are both more efficient and emit fewer pollutants. However, sea-level fuel cells need modifications to be properly used in aircraft applications. At high altitudes, the ambient air has a much lower pressure than at sea level, which makes it much more difficult to get air into the fuel cell to react and produce electricity. Compressors can be used to pressurize the air, but this leads to added weight, volume, and power usage, all of which are undesirable things. Another problem is that fuel cells require hydrogen to create electricity, and ever since the Hindenburg burst into flames, aircraft carrying large quantities of hydrogen have not been in high demand. However, jet fuel is a hydrocarbon, so it is possible to reform it into hydrogen. Since jet fuel is already used to power conventional APUs, it is very convenient to use this to generate the hydrogen for fuel-cell-based APUs. Fuel cells also tend to get large and heavy when used for applications that require a large amount of power. Reducing the size and weight becomes especially beneficial when it comes to fuel cells for aircraft. My goal this summer is to work on several aspects of Aircraft Fuel Cell Power System project. My first goal is to perform checks on a newly built injector rig designed to test different catalysts to determine the best setup for reforming Jet-A fuel into hydrogen. These checks include testing various thermocouples, transmitters, and transducers, as well making sure that the rig was actually built to the design specifications. These checks will help to ensure that the rig will operate properly and give correct results

The development of turbojet aircraft in Germany, Britain, and the United States: A multi-national comparison of aeronautical engineering, 1935--1946

Science.gov (United States)

Pavelec, Sterling Michael

In the 1930s aeronautical engineering needed revision. A presumptive anomaly was envisaged as piston-engine aircraft flew higher and faster. Radical alternatives to piston engines were considered in the unending quest for speed. Concurrently, but unwittingly, two turbojet engine programs were undertaken in Europe. The air-breathing three-stage turbojet engine was based on previous turbine technology; the revolutionary idea was the gas turbine as a prime mover for aircraft. In Germany, Dr. Hans von Ohain was the first to complete a flight-worthy turbojet engine for aircraft. Installed in a Heinkel designed aircraft, the Germans began the jet age on 27 August 1939. The Germans led throughout the war and were the first to produce jet aircraft for combat operations. The principal limiting factor for the German jet program was a lack of reliable engines. The continuing myths that Hitler orders, too little fuel, or too few pilots hindered the program are false. In England, Frank Whittle, without substantial support, but with dogged determination, also developed a turbojet engine. The British came second in the jet race when the Whittle engine powered the Gloster Pioneer on 15 May 1941. The Whittle-Gloster relationship continued and produced the only Allied combat jet aircraft during the war, the Meteor, which was confined to Home Defense in Britain. The American turbojet program was built directly from the Whittle engine. General Electric copied the Whittle designs and Bell Aircraft was contracted to build the first American jet plane. The Americans began the jet age on 1 October 1942 with a lackluster performance from their first jet, the Airacomet. But the Americans forged ahead, and had numerous engine and airframe programs in development by the end of the war. But, the Germans did it right and did it first. Partly because of a predisposition towards excellent engineering and physics, partly out of necessity, the Germans were able to produce combat turbojet aircraft

Cross-cultural adaptation of the Neck Disability Index and Copenhagen Neck Functional Disability Scale for patients with neck pain due to degenerative and discopathic disorders. Psychometric properties of the Polish versions

Directory of Open Access Journals (Sweden)

Glowacki Maciej

2011-04-01

Full Text Available Abstract Background Even though there are several region-specific functional outcome questionnaires measuring neck disorders that have been developed in English-speaking countries, no Polish version has ever been validated. The purpose of our study was to translate, culturally adapt and validate the Neck Disability Index (NDI and Copenhagen Neck Functional Disability Scale (CDS for Polish-speaking patients with neck pain. Methods The translation was carried out according to the International Quality of Life Association (IQOLA Project. Sixty patients were treated due to degenerative and discopathic disorders in the cervical spine filled out the NDI-PL and the CDS-PL. The pain level was evaluated using the Visual Analog Scale. The mean age of the assessed group was 47.1 years (SD 8.9. We used Cronbach's alpha to assess internal consistency. We assessed the test-retest reliability using the Intraclass Correlation Coefficients (ICCs. The Spearman's rank correlation coefficient (rS was used to determine dependency between quantitative characteristics. The Mann-Whitney test was applied to determine dependency between quantitative and qualitative characteristics. Results The Cronbach's alpha values were excellent for the NDI-PL in the test and in the retest (0.84, 0.85, respectively, and for the CDS-PL (0.90 in the test and in the retest. Intraclass Correlation Coefficients were excellent for the CDS-PL and NDI-PL and equalled 0.93 (95% CI from 0.89 to 0.95 and 0.87 (95% CI from 0.80 to 0.92, respectively The concurrent validity was good in the test and in the retest (rs = 0.42 p Conclusions The present versions of the NDI-PL and CDS-PL, the first to be published in Polish, have proven to be reliable and valid for patients with degenerative changes in the cervical spine. The NDI-PL and CDS-PL have excellent internal consistency and test-retest reliability, and good concurrent validity. The adapted questionnaires showed a strong inter-correlation both

Analysis of Aircraft Crash Accident for WETF

International Nuclear Information System (INIS)

Jordan, Hans

2001-01-01

This report applies the methodology of DOE-STD-3014-96, ''Accident Analysis for Aircraft Crash into Hazardous Facilities'', to the Weapons Engineering Tritium Facility (WETF) at LANL. Straightforward application of that methodology shows that including local helicopter flights with those of all other aircraft with potential to impact the facility poses a facility impact risk slightly in excess of the DOE standard's threshold--10 -6 impacts per year. It is also shown that helicopters can penetrate the facility if their engines impact that facility's roof. However, a refinement of the helicopter impact analysis shows that penetration risk of the facility for all aircraft lies below the DOE standard's threshold. By that standard, therefore, the potential for release of hazardous material from the facility as a result of an aircraft crashing into the facility is negligible and need not be analyzed further

Unmanned aircraft system bridge inspection demonstration project phase II final report.

Science.gov (United States)

2017-06-01

An Unmanned Aircraft System (UAS) is defined by the Federal Aviation Administration (FAA) as an aircraft operated without the possibility of direct human intervention from within the aircraft. Unmanned aircraft are familiarly referred to as drones, a...

78 FR 9796 - Airworthiness Directives; Cessna Aircraft Company Airplanes

Science.gov (United States)

2013-02-12

... (2) Model 172S, S/N l72S11074 through 172S11193. (d) Subject Joint Aircraft System Component (JASC)/Air Transport Association (ATA) of America Code 2820, Aircraft Fuel Distribution System. (e) Unsafe... Airworthiness Directives; Cessna Aircraft Company Airplanes AGENCY: Federal Aviation Administration (FAA), DOT...

77 FR 72250 - Airworthiness Directives; Cessna Aircraft Company Airplanes

Science.gov (United States)

2012-12-05

... Joint Aircraft System Component (JASC)/Air Transport Association (ATA) of America Code 2820, Aircraft Fuel Distribution System. (e) Unsafe Condition This AD was prompted by reports of chafing of a new... flight, reinstall the fuel return line assembly (Cessna P/N 0516031-1) following Cessna Aircraft Company...

77 FR 50054 - Airworthiness Directives; Cessna Aircraft Company Airplanes

Science.gov (United States)

2012-08-20

... Aircraft Company Service Bulletin SB04-28-03, dated August 30, 2004, and Engine Fuel Return System... Transport Association (ATA) of America Code 2820, Aircraft Fuel Distribution System. (e) Unsafe Condition... Fuel Return System Modification Do not install Cessna Aircraft Company Service Bulletin SB 04- 28-03...

78 FR 26556 - Airworthiness Directives; Piper Aircraft, Inc. Airplanes

Science.gov (United States)

2013-05-07

... DEPARTMENT OF TRANSPORTATION Federal Aviation Administration 14 CFR Part 39 [Docket No. FAA-2012-0756; Directorate Identifier 2012-CE-012-AD] RIN 2120-AA64 Airworthiness Directives; Piper Aircraft... Piper Aircraft, Inc. (type certificate previously held by The New Piper Aircraft Inc.) Models PA-18 and...

77 FR 67561 - Airworthiness Directives; Univair Aircraft Corporation Airplanes

Science.gov (United States)

2012-11-13

... Airworthiness Directives; Univair Aircraft Corporation Airplanes AGENCY: Federal Aviation Administration (FAA...) that published in the Federal Register. That AD applies to certain Univair Aircraft Corporation Models... throughout the AD for Univair Aircraft Corporation Models (ERCO) 415-C, 415-CD, 415-D, E, G; (Forney) F-1 and...

Examining nocturnal railway noise and aircraft noise in the field: sleep, psychomotor performance, and annoyance.

Science.gov (United States)

Elmenhorst, Eva-Maria; Pennig, Sibylle; Rolny, Vinzent; Quehl, Julia; Mueller, Uwe; Maaß, Hartmut; Basner, Mathias

2012-05-01

Traffic noise is interfering during day- and nighttime causing distress and adverse physiological reactions in large parts of the population. Railway noise proved less annoying than aircraft noise in surveys which were the bases for a so called 5 dB railway bonus regarding noise protection in many European countries. The present field study investigated railway noise-induced awakenings during sleep, nighttime annoyance and the impact on performance the following day. Comparing these results with those from a field study on aircraft noise allowed for a ranking of traffic modes concerning physiological and psychological reactions. 33 participants (mean age 36.2 years ± 10.3 (SD); 22 females) living alongside railway tracks around Cologne/Bonn (Germany) were polysomnographically investigated. These data were pooled with data from a field study on aircraft noise (61 subjects) directly comparing the effects of railway and aircraft noise in one random subject effects logistic regression model. Annoyance was rated in the morning evaluating the previous night. Probability of sleep stage changes to wake/S1 from railway noise increased significantly from 6.5% at 35 dB(A) to 20.5% at 80 dB(A) LAFmax. Rise time of noise events had a significant impact on awakening probability. Nocturnal railway noise led to significantly higher awakening probabilities than aircraft noise, partly explained by the different rise times, whereas the order was inversed for annoyance. Freight train noise compared to passenger train noise proved to have the most impact on awakening probability. Nocturnal railway noise had no effect on psychomotor vigilance. Nocturnal freight train noise exposure in Germany was associated with increased awakening probabilities exceeding those for aircraft noise and contrasting the findings of many annoyance surveys and annoyance ratings of our study. During nighttime a bonus for railway noise seems not appropriate. Copyright © 2012 Elsevier B.V. All rights reserved.

Aircraft Design Software

Science.gov (United States)

1997-01-01

Successful commercialization of the AirCraft SYNThesis (ACSYNT) tool has resulted in the creation of Phoenix Integration, Inc. ACSYNT has been exclusively licensed to the company, an outcome of a seven year, $3 million effort to provide unique software technology to a focused design engineering market. Ames Research Center formulated ACSYNT and in working with the Virginia Polytechnic Institute CAD Laboratory, began to design and code a computer-aided design for ACSYNT. Using a Joint Sponsored Research Agreement, Ames formed an industry-government-university alliance to improve and foster research and development for the software. As a result of the ACSYNT Institute, the software is becoming a predominant tool for aircraft conceptual design. ACSYNT has been successfully applied to high- speed civil transport configuration, subsonic transports, and supersonic fighters.

Aircraft Electric/Hybrid-Electric Power and Propulsion Workshop Perspective of the V/STOL Aircraft Systems Tech Committee

Science.gov (United States)

Hange, Craig E.

2016-01-01

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.

Fuel-Conservation Guidance System for Powered-Lift Aircraft

Science.gov (United States)

Erzberger, Heinz; McLean, John D.

1981-01-01

A technique is described for the design of fuel-conservative guidance systems and is applied to a system that was flight tested on board NASA's sugmentor wing jet STOL research aircraft. An important operational feature of the system is its ability to rapidly synthesize fuel-efficient trajectories for a large set of initial aircraft positions, altitudes, and headings. This feature allows the aircraft to be flown efficiently under conditions of changing winds and air traffic control vectors. Rapid synthesis of fuel-efficient trajectories is accomplished in the airborne computer by fast-time trajectory integration using a simplified dynamic performance model of the aircraft. This technique also ensures optimum flap deployment and, for powered-lift STOL aircraft, optimum transition to low-speed flight. Also included in the design is accurate prediction of touchdown time for use in four-dimensional guidance applications. Flight test results have demonstrated that the automatically synthesized trajectories produce significant fuel savings relative to manually flown conventional approaches.

Investigation of incidents of terrorism involving commercial aircraft.

Science.gov (United States)

Clark, M A; Wagner, G N; Wright, D G; Ruehle, C J; McDonnell, E W

1989-07-01

Deaths resulting from terrorism involving aircraft have occurred incident to hijackings as well as bombings. Passengers or groups of passengers have been chosen by terrorists as the recipients of violence based on citizenship, religion, and political beliefs. They have usually been segregated from other passengers and subsequently mistreated and/or murdered. Thorough documentation of the injuries of victims is essential to the investigation of such atrocities; a medicolegal autopsy correlated with a scene investigation is of paramount importance. Aircraft bombings can create extremely sensitive political situations and public demands for quick resolution. The autopsy of victims in such circumstances, if properly conducted, can yield invaluable trace evidence leading to the identification of the explosive device. The examination of any surviving victims as well as the aircraft is also critical in reconstructing the event. Deaths occurring as the result of in-flight aircraft bombings can produce injuries by five different mechanisms, viz. blast, shrapnel, decompression, impact with the aircraft, and ground impact.

76 FR 70379 - Airworthiness Directives; Cessna Aircraft Company Airplanes

Science.gov (United States)

2011-11-14

...) Subject Joint Aircraft System Component (JASC)/Air Transport Association (ATA) of America Code Fuel, 28...-1245; Directorate Identifier 2011-CE-033-AD; RIN 2120-AA64] Airworthiness Directives; Cessna Aircraft... certain Cessna Aircraft Company (Cessna) Models 172R and 172S airplanes. The existing AD requires you to...

77 FR 42455 - Airworthiness Directives; Piper Aircraft, Inc. Airplanes

Science.gov (United States)

2012-07-19

...-0756; Directorate Identifier 2012-CE-012-AD] RIN 2120-AA64 Airworthiness Directives; Piper Aircraft... adopt a new airworthiness directive (AD) for all Piper Aircraft, Inc. (type certificate previously held by The New Piper Aircraft Inc.) Models PA-18 and PA-19 airplanes. This proposed AD was prompted by...

An aircraft noise pollution model for trajectory optimization

Science.gov (United States)

Barkana, A.; Cook, G.

1976-01-01

A mathematical model describing the generation of aircraft noise is developed with the ultimate purpose of reducing noise (noise-optimizing landing trajectories) in terminal areas. While the model is for a specific aircraft (Boeing 737), the methodology would be applicable to a wide variety of aircraft. The model is used to obtain a footprint on the ground inside of which the noise level is at or above 70 dB.

77 FR 65823 - Control of Air Pollution From Aircraft and Aircraft Engines; Emission Standards and Test Procedures

Science.gov (United States)

2012-10-31

... ENVIRONMENTAL PROTECTION AGENCY 40 CFR Parts 87 [EPA-HQ-OAR-2010-0687; FRL-9678-1] RIN 2060-AO70 Control of Air Pollution From Aircraft and Aircraft Engines; Emission Standards and Test Procedures Correction In rule document 2012-13828 appearing on pages 36341-36386 in the issue of Monday, June 18, 2012, make the following corrections: Sec. 87.2...

Aircraft Wake Vortex Measurement with Coherent Doppler Lidar

Directory of Open Access Journals (Sweden)

Wu Songhua

2016-01-01

Full Text Available Aircraft vortices are generated by the lift-producing surfaces of the aircraft. The variability of near-surface conditions can change the drop rate and cause the cell of the wake vortex to twist and contort unpredictably. The pulsed Coherent Doppler Lidar Detection and Ranging is an indispensable access to real aircraft vortices behavior which transmitting a laser beam and detecting the radiation backscattered by atmospheric aerosol particles. Experiments for Coherent Doppler Lidar measurement of aircraft wake vortices has been successfully carried out at the Beijing Capital International Airport (BCIA. In this paper, the authors discuss the Lidar system, the observation modes carried out in the measurements at BCIA and the characteristics of vortices.

Disability Rating, Age at Death, and Cause of Death in U.S. Veterans with Service-Connected Conditions.

Science.gov (United States)

Maynard, Charles; Trivedi, Ranak; Nelson, Karin; Fihn, Stephan D

2018-03-26

The association between disability and cause of death in Veterans with service-connected disabilities has not been studied. The objective of this study was to compare age at death, military service and disability characteristics, including disability rating, and cause of death by year of birth. We also examined cause of death for specific service-connected conditions. This study used information from the VETSNET file, which is a snapshot of selected items from the Veterans Benefits Administration corporate database. We also used the National Death Index (NDI) for Veterans which is part of the VA Suicide Data Repository. In VETSNET, there were 758,324 Veterans who had a service-connected condition and died between the years 2004 and 2014. Using the scrambled social security number to link the two files resulted in 605,493 (80%) deceased Veterans. Age at death, sex, and underlying cause of death were obtained from the NDI for Veterans and military service characteristics and types of disability were acquired from VETSNET. We constructed age categories corresponding to period of service; birth years 1938 and earlier corresponded to Korea and World War II ("oldest"), birth years 1939-1957 to the Vietnam era ("middle"), and birth years 1958 and later to post Vietnam, Gulf War, and the more recent conflicts in Iraq and Afghanistan ("youngest"). Sixty-two percent were in the oldest age category, 34% in the middle group, and 4% in the youngest one. The overall age at death was 75 ± 13 yr. Only 1.6% of decedents were women; among women 25% were in the youngest age group, while among men only 4% were in the youngest group. Most decedents were enlisted personnel, and 60% served in the U.S. Army. Nearly 61% had a disability rating of >50% and for the middle age group 54% had a disability rating of 100%. The most common service-connected conditions were tinnitus, hearing loss, and post-traumatic stress disorder (PTSD). In the oldest group, nearly half of deaths were due to

A strategic planning methodology for aircraft redesign

Science.gov (United States)

Romli, Fairuz Izzuddin

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

77 FR 52205 - Airworthiness Directives; Univair Aircraft Corporation Airplanes

Science.gov (United States)

2012-08-29

... Airworthiness Directives; Univair Aircraft Corporation Airplanes AGENCY: Federal Aviation Administration (FAA... certain Univair Aircraft Corporation Models (ERCO) 415-C, 415-CD, 415-D, E, G; (Forney) F-1 and F-1A... inspection results. This new AD was prompted by a report of a Univair Aircraft Corporation Model ERCO 415-D...

Application of variable structure system theory to aircraft flight control. [AV-8A and the Augmentor Wing Jet STOL Research Aircraft

Science.gov (United States)

Calise, A. J.; Kadushin, I.; Kramer, F.

1981-01-01

The current status of research on the application of variable structure system (VSS) theory to design aircraft flight control systems is summarized. Two aircraft types are currently being investigated: the Augmentor Wing Jet STOL Research Aircraft (AWJSRA), and AV-8A Harrier. The AWJSRA design considers automatic control of longitudinal dynamics during the landing phase. The main task for the AWJSRA is to design an automatic landing system that captures and tracks a localizer beam. The control task for the AV-8A is to track velocity commands in a hovering flight configuration. Much effort was devoted to developing computer programs that are needed to carry out VSS design in a multivariable frame work, and in becoming familiar with the dynamics and control problems associated with the aircraft types under investigation. Numerous VSS design schemes were explored, particularly for the AWJSRA. The approaches that appear best suited for these aircraft types are presented. Examples are given of the numerical results currently being generated.

Integrated controls pay-off. [for flight/propulsion aircraft systems

Science.gov (United States)

Putnam, Terrill W.; Christiansen, Richard S.

1989-01-01

It is shown that the integration of the propulsion and flight control systems for high performance aircraft can help reduce pilot workload while simultaneously increasing overall aircraft performance. Results of the Highly Integrated Digital Electronic Control (HiDEC) flight research program are presented to demonstrate the emerging payoffs of controls integration. Ways in which the performance of fighter aircraft can be improved through the use of propulsion for primary aircraft control are discussed. Research being conducted by NASA with the F-18 High Angle-of Attack Research Vehicle is described.

78 FR 25363 - Airworthiness Directives; Diamond Aircraft Industries Airplanes

Science.gov (United States)

2013-05-01

... holidays. For service information identified in this AD, contact Diamond Aircraft Industries GmbH, N.A... Aircraft Industries GmbH has issued Mandatory Service Bulletin 40NG-018/1, dated November 20, 2012. The... Aircraft Industries GmbH Mandatory Service Bulletin 40NG-018/1, dated November 26, 2012. (2) If chafing...

Design Of Vertical Take-Off And Landing VTOL Aircraft System

Directory of Open Access Journals (Sweden)

Win Ko Ko Oo

2017-04-01

Full Text Available Vertical Take Off and Landing Vehicles VTOL are the ones which can take off and land from the same place without need of long runway. This paper presents the design and implementation of tricopter mode and aircraft mode for VTOL aircraft system. Firstly the aircraft design is considered for VTOL mode. And then the mathematical model of the VTOL aircraft is applied to test stability. In this research the KK 2.1 flight controller is used for VTOL mode and aircraft mode. The first part is to develop the VTOL mode and the next part is the transition of VTOL mode to aircraft mode. This paper gives brief idea about numerous types of VTOLs and their advantages over traditional aircraftsand insight to various types of tricopter and evaluates their configurations.

Fast Aircraft Turnaround Enabled by Reliable Passenger Boarding

OpenAIRE

Michael Schultz

2018-01-01

Future 4D aircraft trajectories demand comprehensive consideration of environmental, economic, and operational constraints, as well as reliable prediction of all aircraft-related processes. Mutual interdependencies between airports result in system-wide, far-reaching effects in the air traffic network (reactionary delays). To comply with airline/airport challenges over the day of operations, a change to an air-to-air perspective is necessary, with a specific focus on the aircraft ground opera...

Inductive sensor for lightning current measurement, fitted in aircraft windows, part II: Measurements on an A320 aircraft

NARCIS (Netherlands)

Deursen, van A.P.J.

2011-01-01

A novel sensor for the detection of the lightning current through the fuselage of an aircraft has been tested on an A320 aircraft. An accurate method-of-moment model of the window edge provided reliable calibration of the sensor for external fields. The data have been analyzed and the good

Aircraft bi-level life cycle cost estimation

NARCIS (Netherlands)

Zhao, X.; Verhagen, W.J.C.; Curan, R.

2015-01-01

n an integrated aircraft design and analysis practice, Life Cycle Cost (LCC) is essential for decision making. The LCC of an aircraft is ordinarily partially estimated by emphasizing a specific cost type. However, an overview of the LCC including design and development cost, production cost,

Fault Tolerance, Diagnostics, and Prognostics in Aircraft Flight

Data.gov (United States)

National Aeronautics and Space Administration — Abstract In modern fighter aircraft with statically unstable airframe designs, the flight control system is considered flight critical, i.e. the aircraft will...

Alternate aircraft fuels prospects and operational implications

Science.gov (United States)

Witcofski, R. D.

1977-01-01

The paper discusses NASA studies of the potentials of coal-derived aviation fuels, specifically synthetic aviation kerosene, liquid methane, and liquid hydrogen. Topics include areas of fuel production, air terminal requirements for aircraft fueling (for liquid hydrogen only), and the performance characteristics of aircraft designed to utilize alternate fuels. Energy requirements associated with the production of each of the three selected fuels are determined, and fuel prices are estimated. Subsonic commercial air transports using liquid hydrogen fuel have been analyzed, and their performance and the performance of aircraft which use commercial aviation kerosene are compared. Environmental and safety issues are considered.

78 FR 56150 - Airworthiness Directives; Piper Aircraft, Inc. Airplanes

Science.gov (United States)

2013-09-12

... Airworthiness Directives; Piper Aircraft, Inc. Airplanes AGENCY: Federal Aviation Administration (FAA), DOT... published in the Federal Register. AD 2013-13-01 applies to certain Piper Aircraft, Inc. Models PA-46-310P... nitrile parts are installed for certain Piper Aircraft, Inc. Models PA-46-310P, PA-46-350P, PA-46R-350T...

Aircraft and background noise annoyance effects

Science.gov (United States)

Willshire, K. F.

1984-01-01

To investigate annoyance of multiple noise sources, two experiments were conducted. The first experiment, which used 48 subjects, was designed to establish annoyance-noise level functions for three community noise sources presented individually: jet aircraft flyovers, air conditioner, and traffic. The second experiment, which used 216 subjects, investigated the effects of background noise on aircraft annoyance as a function of noise level and spectrum shape; and the differences between overall, aircraft, and background noise annoyance. In both experiments, rated annoyance was the dependent measure. Results indicate that the slope of the linear relationship between annoyance and noise level for traffic is significantly different from that of flyover and air conditioner noise and that further research was justified to determine the influence of the two background noises on overall, aircraft, and background noise annoyance (e.g., experiment two). In experiment two, total noise exposure, signal-to-noise ratio, and background source type were found to have effects on all three types of annoyance. Thus, both signal-to-noise ratio, and the background source must be considered when trying to determine community response to combined noise sources.

Strategic Conflict Detection and Resolution Using Aircraft Intent Information

Science.gov (United States)

Porretta, Marco; Schuster, Wolfgang; Majumdar, Arnab; Ochieng, Washington

A number of automated decision support tools will be required in the future air traffic management system to enable continued provision of safe and efficient services in increasingly congested skies. In particular, Conflict Detection and Resolution (CDR) tools should allow for early detection of possible conflicts and propose safe and efficient resolution manoeuvres to avoid loss of separation. However, current approaches in the open literature not only use different levels of aircraft intent information but also make a number of assumptions on models of aircraft motion. Furthermore, information relevant to aircraft performance is often not considered with the consequence of the resulting resolution strategies being potentially unreliable. This paper presents an enhanced, strategic, pairwise, performance-based and distributed CDR algorithm. It accounts for the weaknesses of current approaches by using the maximum level of aircraft intent information together with a novel trajectory prediction model. Numerical results for representative conflict scenarios show that the proposed CDR method is able to generate conflict-free trajectories for participating aircraft while taking into account the actual aircraft capabilities to perform the recommended resolution manoeuvres.

Visit to China's ARJ21 Aircraft Manufacturing Facility

National Research Council Canada - National Science Library

Balut, Stephen J; McNicol, David L; Nelson, J. R; Harmon, Bruce R; Holder, Stephen G

2008-01-01

During a December 2007 visit to China to share information about civilian aircraft costs, a delegation from IDA visited the Shanghai Aircraft Manufacturing Facility where the commercial chinese ARJ21...

Modular Electric Propulsion Test Bed Aircraft, Phase I

Data.gov (United States)

National Aeronautics and Space Administration — An all electric aircraft test bed is proposed to provide a dedicated development environment for the rigorous study and advancement of electrically powered aircraft....

Robotics and Automation for Flight Deck Aircraft Servicing

Energy Technology Data Exchange (ETDEWEB)

Chesser, J.B.; Draper, J.V.; Pin, F.G.

1999-03-01

One of the missions of the Future Aircraft Carriers Program is to investigate methods that would improve aircraft turnaround servicing activities on carrier decks. The major objectives and criteria for evaluating alternative aircraft servicing methods are to reduce workload requirements, turnaround times (TAT), and life-cycle costs (LCC). Technologies in the field of Robotics and Automation (R and A) have the potential to significantly contribute to these objectives. The objective of this study was to investigate aircraft servicing functions on carrier decks which would offer the potentially most significant payoff if improved by various R and A technologies. Improvement in this case means reducing workload, time and LCC. This objective was accomplished using a ''bottom-up'' formalized approach as described in the following.

Model of aircraft noise adaptation

Science.gov (United States)

Dempsey, T. K.; Coates, G. D.; Cawthorn, J. M.

1977-01-01

Development of an aircraft noise adaptation model, which would account for much of the variability in the responses of subjects participating in human response to noise experiments, was studied. A description of the model development is presented. The principal concept of the model, was the determination of an aircraft adaptation level which represents an annoyance calibration for each individual. Results showed a direct correlation between noise level of the stimuli and annoyance reactions. Attitude-personality variables were found to account for varying annoyance judgements.

Seat Capacity Selection for an Advanced Short-Haul Aircraft Design

Science.gov (United States)

Marien, Ty V.

2016-01-01

A study was performed to determine the target seat capacity for a proposed advanced short-haul aircraft concept projected to enter the fleet by 2030. This analysis projected the potential demand in the U.S. for a short-haul aircraft using a transportation theory approach, rather than selecting a target seat capacity based on recent industry trends or current market demand. A transportation systems model was used to create a point-to-point network of short-haul trips and then predict the number of annual origin-destination trips on this network. Aircraft of varying seat capacities were used to meet the demand on this network, assuming a single aircraft type for the entire short-haul fleet. For each aircraft size, the ticket revenue and operational costs were used to calculate a total market profitability metric for all feasible flights. The different aircraft sizes were compared, based on this market profitability metric and also the total number of annual round trips and markets served. Sensitivity studies were also performed to determine the effect of changing the aircraft cruise speed and maximum trip length. Using this analysis, the advanced short-haul aircraft design team was able to select a target seat capacity for their design.

Back and neck pain among school teachers in Poland and its correlations with physical activity

Directory of Open Access Journals (Sweden)

Jerzy Rottermund

2015-12-01

Full Text Available Background: Back pain represents one of the most common diseases across various populations of workers worldwide. This study analyzes the prevalence and severity of back pain, based on selected demographic variables, and the relationship with physical activity among school teachers. Material and Methods: The study included 998 professionally active teachers (840 females and 158 males from the southern part of Poland. Validated psychometric tools, namely: 1 for evaluation of disability due to back pain – a Polish version of the Oswestry Disability Index (ODI and Neck Disability Index (NDI, 2 for physical activity assessment – the Subjective Experience of Work Load (SEWL as well as the authors’ supplementary questionnaire, addressing demographic and anthropometric variables were used. Results: There was no correlation between age and the NDI scores in females (r = 0.027, in contrast to males (r = 0.202; p ≤ 0.05. Statistically significant correlations (p ≤ 0.05 were reported between: age and the ODI, in both females (r = 0.219 and males (r = 0.180. No associations between the body mass index (BMI-ODI, and BMI-NDI were found. In the case of women, disability related to low back pain (LBP had a negative impact on the indicators of their activity during work, sports, and leisure time. In the case of men, the NDI and ODI scores did not differ, based on activity indicators. Conclusions: Our findings confirm that back pain represents a serious concern among teachers. Age appears to be a prognostic factor, while no association between the BMI and LBP has been revealed. The limitation of physical activity leads to more frequent back pain. Med Pr 2015;66(6:771–778

Aircraft dynamic loads generated in wake vortex encounters

OpenAIRE

Suñer Perucho, Carles

2014-01-01

The study illustrated in these pages was developed in the Structural Dynamics and Aeroelasticity Department of the Military Aircraft division of Airbus Defence and Space in Getafe, Madrid (Spain). That department is a multidisciplinary one involving several categories. Some of its competences are the analysis of impacts, acoustics and vibrations for the aircraft and all their systems. Also, the dynamic response of the aircraft to different events is part of the tasks for that department. It i...

Wind Information Uplink to Aircraft Performing Interval Management Operations

Science.gov (United States)

Ahmad, Nashat N.; Barmore, Bryan E.; Swieringa, Kurt A.

2016-01-01

Interval Management (IM) is an ADS-B-enabled suite of applications that use ground and flight deck capabilities and procedures designed to support the relative spacing of aircraft (Barmore et al., 2004, Murdoch et al. 2009, Barmore 2009, Swieringa et al. 2011; Weitz et al. 2012). Relative spacing refers to managing the position of one aircraft to a time or distance relative to another aircraft, as opposed to a static reference point such as a point over the ground or clock time. This results in improved inter-aircraft spacing precision and is expected to allow aircraft to be spaced closer to the applicable separation standard than current operations. Consequently, if the reduced spacing is used in scheduling, IM can reduce the time interval between the first and last aircraft in an overall arrival flow, resulting in increased throughput. Because IM relies on speed changes to achieve precise spacing, it can reduce costly, low-altitude, vectoring, which increases both efficiency and throughput in capacity-constrained airspace without negatively impacting controller workload and task complexity. This is expected to increase overall system efficiency. The Flight Deck Interval Management (FIM) equipment provides speeds to the flight crew that will deliver them to the achieve-by point at the controller-specified time, i.e., assigned spacing goal, after the target aircraft crosses the achieve-by point (Figure 1.1). Since the IM and target aircraft may not be on the same arrival procedure, the FIM equipment predicts the estimated times of arrival (ETA) for both the IM and target aircraft to the achieve-by point. This involves generating an approximate four-dimensional trajectory for each aircraft. The accuracy of the wind data used to generate those trajectories is critical to the success of the IM operation. There are two main forms of uncertainty in the wind information used by the FIM equipment. The first is the accuracy of the forecast modeling done by the weather

Rankine-Brayton engine powered solar thermal aircraft

Science.gov (United States)

Bennett, Charles L [Livermore, CA

2009-12-29

A solar thermal powered aircraft powered by heat energy from the sun. A Rankine-Brayton hybrid cycle heat engine is carried by the aircraft body for producing power for a propulsion mechanism, such as a propeller or other mechanism for enabling sustained free flight. The Rankine-Brayton engine has a thermal battery, preferably containing a lithium-hydride and lithium mixture, operably connected to it so that heat is supplied from the thermal battery to a working fluid. A solar concentrator, such as reflective parabolic trough, is movably connected to an optically transparent section of the aircraft body for receiving and concentrating solar energy from within the aircraft. Concentrated solar energy is collected by a heat collection and transport conduit, and heat transported to the thermal battery. A solar tracker includes a heliostat for determining optimal alignment with the sun, and a drive motor actuating the solar concentrator into optimal alignment with the sun based on a determination by the heliostat.

Rankline-Brayton engine powered solar thermal aircraft

Science.gov (United States)

Bennett, Charles L [Livermore, CA

2012-03-13

A solar thermal powered aircraft powered by heat energy from the sun. A Rankine-Brayton hybrid cycle heat engine is carried by the aircraft body for producing power for a propulsion mechanism, such as a propeller or other mechanism for enabling sustained free flight. The Rankine-Brayton engine has a thermal battery, preferably containing a lithium-hydride and lithium mixture, operably connected to it so that heat is supplied from the thermal battery to a working fluid. A solar concentrator, such as reflective parabolic trough, is movably connected to an optically transparent section of the aircraft body for receiving and concentrating solar energy from within the aircraft. Concentrated solar energy is collected by a heat collection and transport conduit, and heat transported to the thermal battery. A solar tracker includes a heliostat for determining optimal alignment with the sun, and a drive motor actuating the solar concentrator into optimal alignment with the sun based on a determination by the heliostat.

Access improvement to aircraft passengers' hand luggage.

Science.gov (United States)

Alberda, W; Kampinga, O; Kassels, R; van Kester, R; Noriega, J; Vink, P

2015-01-01

Efficient use of space and passenger comfort in aircraft interiors are major issues. There is not much research available about the flying experience regarding passengers' personal belongings. The objective of this study is to explore concepts within the current aircraft seats which improve the passenger experience related to their personal belongings like wallets, mobile phones and laptops. Through on-site observations, interviews and online questionnaires, data regarding the number of personal belongings taken into the airplane and opinions about access to hand luggage were gathered. These data were used to develop different concepts to optimize the aircraft interior, which were evaluated by passengers. Almost every passenger carries a phone (88%), wallet (94%), travel documents (98%) and keys (76%) with them and they like to have these stored close by. Passengers rate the concept that provides integrated storage in the tray table of the aircraft seat the best. Extra storage possibility in the table-tray seems a promising solution according to the passengers.

FAA-NASA Sixth International Conference on the Continued Airworthiness of Aircraft Structures

Science.gov (United States)

1995-12-01

Administration, and Colin G. Drury , State University of New York at Buffalo The Aging Aircraft Nondestructive Inspection Validation Center - A R esource for...William T. Shepherd FAA-Office of Aviation Medicine Washington, DC and Colin G. Drury State University of New York at Buffalo Buffalo, NY INTRODUCTION FAA’s...improvement, changing the task, the operator (inspector), machine, or environment as appropriate, e.g., review in Drury , 1992 (Ref. 1). 2. From the

MD-11 PCA - View of aircraft on ramp

Science.gov (United States)

1995-01-01

This McDonnell Douglas MD-11 is taxiing to a position on the flightline at NASA's Dryden Flight Research Center, Edwards, California, following its completion of the first and second landings ever performed by a transport aircraft under engine power only (on Aug. 29, 1995). The milestone flight, with NASA research pilot and former astronaut Gordon Fullerton at the controls, was part of a NASA project to develop a computer-assisted engine control system that enables a pilot to land a plane safely when its normal control surfaces are disabled. The Propulsion-Controlled Aircraft (PCA) system uses standard autopilot controls already present in the cockpit, together with the new programming in the aircraft's flight control computers. The PCA concept is simple. For pitch control, the program increases thrust to climb and reduces thrust to descend. To turn right, the autopilot increases the left engine thrust while decreasing the right engine thrust. The initial Propulsion-Controlled Aircraft studies by NASA were carried out at Dryden with a modified twin-engine F-15 research aircraft.

Determination of tricresyl phosphate air contamination in aircraft.

Science.gov (United States)

Denola, G; Hanhela, P J; Mazurek, W

2011-08-01

Monitoring of tricresyl phosphate (TCP) contamination of cockpit air was undertaken in three types of military aircraft [fighter trainer (FT), fighter bomber (FB), and cargo transport (CT) aircraft]. The aircraft had a previous history of pilot complaints about cockpit air contamination suspected to originate from the engine bleed air supply through the entry of aircraft turbine engine oil (ATO) into the engine compressor. Air samples were collected in flight and on the ground during engine runs using sorbent tubes packed with Porapak Q and cellulose filters. A total of 78 air samples were analysed, from 46 different aircraft, and 48 samples were found to be below the limit of detection. Nine incidents of smoke/odour were identified during the study. The concentrations of toxic o-cresyl phosphate isomers were below the level of detection in all samples. The highest total TCP concentration was 51.3 μg m(-3), while most were generally found to be contamination of cabin/cockpit air has been the subject of much concern in aviation, quantitative data are sparse.

A manpower scheduling heuristic for aircraft maintenance application

Science.gov (United States)

Sze, San-Nah; Sze, Jeeu-Fong; Chiew, Kang-Leng

2012-09-01

This research studies a manpower scheduling for aircraft maintenance, focusing on in-flight food loading operation. A group of loading teams with flexible shifts is required to deliver and upload packaged meals from the ground kitchen to aircrafts in multiple trips. All aircrafts must be served within predefined time windows. The scheduling process takes into account of various constraints such as meal break allocation, multi-trip traveling and food exposure time limit. Considering the aircrafts movement and predefined maximum working hours for each loading team, the main objective of this study is to form an efficient roster by assigning a minimum number of loading teams to the aircrafts. We proposed an insertion based heuristic to generate the solutions in a short period of time for large instances. This proposed algorithm is implemented in various stages for constructing trips due to the presence of numerous constraints. The robustness and efficiency of the algorithm is demonstrated in computational results. The results show that the insertion heuristic more efficiently outperforms the company's current practice.

Study of LH2 fueled subsonic passenger transport aircraft

Science.gov (United States)

Brewer, G. D.; Morris, R. E.

1976-01-01

The potential of using liquid hydrogen as fuel in subsonic transport aircraft was investigated to explore an expanded matrix of passenger aircraft sizes. Aircraft capable of carrying 130 passengers 2,780 km (1500 n.mi.); 200 passengers 5,560 km (3000 n.mi.); and 400 passengers on a 9,265 km (5000 n.mi.) radius mission, were designed parametrically. Both liquid hydrogen and conventionally fueled versions were generated for each payload/range in order that comparisons could be made. Aircraft in each mission category were compared on the basis of weight, size, cost, energy utilization, and noise.

Judgments of aircraft noise in a traffic noise background

Science.gov (United States)

Powell, C. A.; Rice, C. G.

1975-01-01

An investigation was conducted to determine subjective response to aircraft noise in different road traffic backgrounds. In addition, two laboratory techniques for presenting the aircraft noise with the background noise were evaluated. For one technique, the background noise was continuous over an entire test session; for the other, the background noise level was changed with each aircraft noise during a session. Subjective response to aircraft noise was found to decrease with increasing background noise level, for a range of typical indoor noise levels. Subjective response was found to be highly correlated with the Noise Pollution Level (NPL) measurement scale.

Intelligent Aircraft Damage Assessment, Trajectory Planning, and Decision-Making under Uncertainty

Science.gov (United States)

Lopez, Israel; Sarigul-Klijn, Nesrin

Situational awareness and learning are necessary to identify and select the optimal set of mutually non-exclusive hypothesis in order to maximize mission performance and adapt system behavior accordingly. This paper presents a hierarchical and decentralized approach for integrated damage assessment and trajectory planning in aircraft with uncertain navigational decision-making. Aircraft navigation can be safely accomplished by properly addressing the following: decision-making, obstacle perception, aircraft state estimation, and aircraft control. When in-flight failures or damage occur, rapid and precise decision-making under imprecise information is required in order to regain and maintain control of the aircraft. To achieve planned aircraft trajectory and complete safe landing, the uncertainties in system dynamics of the damaged aircraft need to be learned and incorporated at the level of motion planning. The damaged aircraft is simulated via a simplified kinematic model. The different sources and perspectives of uncertainties in the damage assessment process and post-failure trajectory planning are presented and classified. The decision-making process for an emergency motion planning and landing is developed via the Dempster-Shafer evidence theory. The objective of the trajectory planning is to arrive at a target position while maximizing the safety of the aircraft given uncertain conditions. Simulations are presented for an emergency motion planning and landing that takes into account aircraft dynamics, path complexity, distance to landing site, runway characteristics, and subjective human decision.

Advanced energy systems (APU) for large commercial aircraft

Energy Technology Data Exchange (ETDEWEB)

Westenberger, A.; Bleil, J.; Arendt, M. [Airbus Deutschland GmbH, Hamburg (Germany)

2013-06-01

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.)

Robust Control of an Ill-Conditioned Aircraft

DEFF Research Database (Denmark)

Breslin, S.G.; Tøffner-Clausen, S.; Grimble, M.J.

1996-01-01

A robust controller is designed for a linear model of an Advanced Short Take-Off and Vertical Landing (ASTOVL) aircraft at one operating point.......A robust controller is designed for a linear model of an Advanced Short Take-Off and Vertical Landing (ASTOVL) aircraft at one operating point....

Stability Result For Dynamic Inversion Devised to Control Large Flexible Aircraft

Science.gov (United States)

Gregory, Irene M.

2001-01-01

High performance aircraft of the future will be designed lighter, more maneuverable, and operate over an ever expanding flight envelope. One of the largest differences from the flight control perspective between current and future advanced aircraft is elasticity. Over the last decade, dynamic inversion methodology has gained considerable popularity in application to highly maneuverable fighter aircraft, which were treated as rigid vehicles. This paper is an initial attempt to establish global stability results for dynamic inversion methodology as applied to a large, flexible aircraft. This work builds on a previous result for rigid fighter aircraft and adds a new level of complexity that is the flexible aircraft dynamics, which cannot be ignored even in the most basic flight control. The results arise from observations of the control laws designed for a new generation of the High-Speed Civil Transport aircraft.

Depreciation of aircraft

Science.gov (United States)

Warner, Edward P

1922-01-01

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

F-15 PCA (Propulsion Controlled Aircraft) Simulation Cockpit

Science.gov (United States)

1990-01-01

The F-15 PCA (Propulsion Controlled Aircraft) simulation was used from 1990 to 1993. It was used for the development of propulsion algorithms and piloting techniques (using throttles only) to be used for emergency flight control in the advent of a major flight control system failure on a multi-engine aircraft. Following this program with the Dryden F-15, similiar capabilities were developed for other aircraft, such as the B-720, Lear 24, B-727, C-402, and B-747.

76 FR 51986 - Agency Information Collection Activities; Submission for Office of Management and Budget Review...

Science.gov (United States)

2011-08-19

... distributor of a dietary supplement containing an NDI, or of an NDI, to submit to the Office of Nutrition...-text scientific journal articles and obtaining legal review of NDI notifications. (Response) FDA... summarize information for NDI notifications, paying for full-text scientific journal articles and obtaining...

77 FR 45480 - Deductions for Entertainment Use of Business Aircraft

Science.gov (United States)

2012-08-01

... Deductions for Entertainment Use of Business Aircraft AGENCY: Internal Revenue Service (IRS), Treasury... business aircraft for entertainment. These final regulations affect taxpayers that deduct expenses for... section 274 of the Internal Revenue Code (Code) of deductions for the use of business aircraft for...

Aerodynamics/ACEE: Aircraft energy efficiency

Science.gov (United States)

1981-01-01

An overview is presented of a 10 year program managed by NASA which seeks to make possible the most efficient use of energy for aircraft propulsion and lift as well as provide a technology that can be used by U.S. manufacturers of air transports and engines. Supercritical wings, winglets, vortex drag reduction, high lift, active control, laminar flow control, and aerodynamics by computer are among the topics discussed. Wind tunnel models in flight verification of advanced technology, and the design, construction and testing of various aircraft structures are also described.

Multidisciplinary Techniques and Novel Aircraft Control Systems

Science.gov (United States)

Padula, Sharon L.; Rogers, James L.; Raney, David L.

2000-01-01

The Aircraft Morphing Program at NASA Langley Research Center explores opportunities to improve airframe designs with smart technologies. Two elements of this basic research program are multidisciplinary design optimization (MDO) and advanced flow control. This paper describes examples where MDO techniques such as sensitivity analysis, automatic differentiation, and genetic algorithms contribute to the design of novel control systems. In the test case, the design and use of distributed shape-change devices to provide low-rate maneuvering capability for a tailless aircraft is considered. The ability of MDO to add value to control system development is illustrated using results from several years of research funded by the Aircraft Morphing Program.

Aircraft Anomaly Detection Using Performance Models Trained on Fleet Data

Science.gov (United States)

Gorinevsky, Dimitry; Matthews, Bryan L.; Martin, Rodney

2012-01-01

This paper describes an application of data mining technology called Distributed Fleet Monitoring (DFM) to Flight Operational Quality Assurance (FOQA) data collected from a fleet of commercial aircraft. DFM transforms the data into aircraft performance models, flight-to-flight trends, and individual flight anomalies by fitting a multi-level regression model to the data. The model represents aircraft flight performance and takes into account fixed effects: flight-to-flight and vehicle-to-vehicle variability. The regression parameters include aerodynamic coefficients and other aircraft performance parameters that are usually identified by aircraft manufacturers in flight tests. Using DFM, the multi-terabyte FOQA data set with half-million flights was processed in a few hours. The anomalies found include wrong values of competed variables, (e.g., aircraft weight), sensor failures and baises, failures, biases, and trends in flight actuators. These anomalies were missed by the existing airline monitoring of FOQA data exceedances.

Cycle Counting Methods of the Aircraft Engine

Science.gov (United States)

Fedorchenko, Dmitrii G.; Novikov, Dmitrii K.

2016-01-01

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

14 CFR 13.17 - Seizure of aircraft.

Science.gov (United States)

2010-01-01

... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Seizure of aircraft. 13.17 Section 13.17... INVESTIGATIVE AND ENFORCEMENT PROCEDURES Legal Enforcement Actions § 13.17 Seizure of aircraft. (a) Under... officer, or a Federal Aviation Administration safety inspector, authorized in an order of seizure issued...

Developing the Total Disability Index Based on an Analysis of the Interrelationships and Limitations of Oswestry and Neck Disability Index.

Science.gov (United States)

Spiegel, Matthew A; Lafage, Renaud; Lafage, Virginie; Ryan, Devon; Marascalchi, Bryan; Trimba, Yuriy; Ames, Christopher; Harris, Bradley; Tanzi, Elizabeth; Oren, Jonathan; Vira, Shaleen; Errico, Thomas; Schwab, Frank; Protopsaltis, Themistocles S

2016-01-01

Retrospective. This study assessed the feasibility of combining Oswestry and Neck Disability Index (ODI and NDI) into 1 shorter "Total Disability Index" (TDI) from which reconstructed scores could be computed. ODI and NDI are not pure assessments of disability related to back and neck, respectively. Because of similarities/redundancies of questions, ODI scores may be elevated in neck-pain patients and the converse is true for NDI in back-pain patients. Spine patients completed ODI and NDI, and complaints were recorded as back pain (BP), neck pain (NP), or both (BNP). Questionnaire scores were compared across cohorts via descriptives and Spearman (ρ) correlations. In exploring the feasibility of merging ODI/NDI, TDI was constructed from 9 ODI and 5 NDI items. Extracting questions from TDI, reconstructed 9-item rODI and 10-item rNDI indices were formed and compared with true ODI/NDI. There were a total of 1207 patients: 741 BP, 134 NP, and 268 BNP. Mean ODI was 37 ± 21 and mean NDI was 32 ± 21. Patients with concurrent BP and NP had significantly more disability. Seventy-eight patients of 134 (58%) patients with NP only had at least "moderate disability" by ODI and 297 of 741 (40%) patients with back pain only, had at least "moderate disability" by NDI. ODI versus NDI correlation was ρ = 0.755; ODI versus reconstructed rODI correlated at ρ = 0.985, and NDI versus reconstructed rNDI correlated at ρ = 0.967 (P disability in 1 region affects scores on both surveys. This study constructed a 14-item TDI that represents every domain of ODI/NDI with exception of ODI "Sex Life." From this TDI, reconstructed scores correlated near perfectly with true scores. TDI provides a more global assessment of spinal disability and is a questionnaire that reduces the time burden to patients. The TDI allows for simultaneous assessment of back, neck, and global spinal disability.

The community response to aircraft noise around six Spanish airports

Science.gov (United States)

Garcia, A.; Faus, L. J.; Garcia, A. M.

1993-06-01

The community response to aircraft noise has been studied through a social survey. A total of 1800 persons living in the vicinity of six major Spanish airports have been interviewed at their homes concerning the environmental quality of the area, dissatisfaction with road traffic noise and aircraft noise, activities interfered with by noise, most disturbing aircraft types, and subjective evaluation of airport impact. All the responses obtained in this survey have been compared with aircraft noise levels corresponding to the residence locations of the people interviewed (values of NEF levels were calculated with the INM model). The results obtained in this work allow one to evaluate the impact of aircraft noise under a wide range of different situations.

Aircraft Crash Survival Design Guide. Volume 5. Aircraft Postcrash Survival

Science.gov (United States)

1980-01-01

neck Access door toprille capm enrFuel tank Figue 3. Fangblefiler eckinsalgbelati n. A-j L)n wal Aircraft skin Frangible filler neck Failure plane...This is because a number of major assumptions must be made in the extrapolation: the smoke generated is uniformly distri- buted and is independent

Liens on aircraft with special reference on statutory liens

Directory of Open Access Journals (Sweden)

Janković Svetislav

2014-01-01

Full Text Available The paper examines three types of liens on aircraft: mortgage (as contractual lien, statutory and judicial lien on aircraft. Special attention is paid to statutory liens and its relationship with mortgage and judicial lien on same aircraft. The author highlights the problem of priority of different type of secured creditors due to the fact of existing competition between their interests. This problem is especially enlarged because of simultaneously applying three different source of law: Cape Town Convention 2001, Serbian Law of Air Transport 2011 and Geneva Convention on the Recognition of Rights in Aircraft 1948. Conclusion is that the creditor with statutory lien on aircraft has the biggest priority in realization of his right over other creditors and even creditors secured with mortgage and judicial lien which have priority between themselves in comply with principle 'first in time, first in right'. In order to achieve the ideas of this conclusion in practice it is necessary for courts to use teleological interpretation in applying laws. This is especially because of certain inconsistencies between different legal sources in regard of notion, order of priority and effect of different type of liens on aircraft.

Energy optimization analysis of the more electric aircraft

Science.gov (United States)

Liu, Yitao; Deng, Junxiang; Liu, Chao; Li, Sen

2018-02-01

The More Electric Aircraft (MEA) underlines the utilization of the electrical power to drive the non-propulsive aircraft systems. The critical features of the MEA including no-bleed engine architecture and advanced electrical system are introduced. Energy and exergy analysis is conducted for the MEA, and comparison of the effectiveness and efficiency of the energy usage between conventional aircraft and the MEA is conducted. The results indicate that one of the advantages of the MEA architecture is the greater efficiency gained in terms of reduced fuel consumption.

Weed detection using unmanned aircraft vehicles

Directory of Open Access Journals (Sweden)

Pflanz, Michael

2014-03-01

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

Unmanned Aircraft Systems: The Road to Effective Integration

National Research Council Canada - National Science Library

Petrock, Christopher T; Huizenga, Thomas D

2006-01-01

...) sharing airspace with manned assets. There have been at least two recent collisions between unmanned and rotary-wing aircraft at lower altitudes in Iraq, as well as numerous near misses with fixed-wing aircraft at higher altitudes...

A Rare Case of Congenital Diabetes Insipidus

Directory of Open Access Journals (Sweden)

Tanvi eRege

2015-07-01

Full Text Available Congenital nephrogenic diabetes insipidus (NDI is a conformation disease resulting from protein misfolding. Ninety percent of mutations result from the inactivating mutations of the arginine vasopressin receptor 2 (AVPR2 gene transmitted in an X-linked fashion, blocking the response to vasopressin, resulting in the inability to concentrate urine. Clinical features include polyuria, polydipsia, dehydration, and hypernatremia. They are generally more severely in affected males but present variably in females due to skewed inactivation of the X chromosome. We describe a case of a 40 year old woman with a history of Type 2 diabetes mellitus, hyperlipidemia, and obesity who presents with debilitating polyuria since the age of five with no clear diagnosis. Interestingly, her son was subsequently diagnosed with NDI. Genetic testing revealed that she was heterozygous for the Val88Met mutation in the AVPR2 gene while her son was hemizygous for the same. The patient has since been successfully treated with diuretics and a low solute diet. We highlight that although X-linked NDI patients are mostly males, it should be considered in symptomatic females to prevent delays in the diagnosis. Conformational diseases such as NDI are presently the subject of research using pharmacological chaperones to restore proper receptor membrane localization and function.

A Rare Case of Congenital Diabetes Insipidus.

Science.gov (United States)

Rege, Tanvi; Polsani, Srujana; Jim, Belinda

2015-01-01

Congenital nephrogenic diabetes insipidus (NDI) is a conformation disease resulting from protein misfolding. Ninety percent of mutations result from the inactivating mutations of the arginine vasopressin receptor 2 (AVPR2) gene transmitted in an X-linked fashion, blocking the response to vasopressin, resulting in the inability to concentrate urine. Clinical features include polyuria, polydispsia, dehydration, and hypernatremia. They are generally more severely in affected males but present variably in females due to skewed inactivation of the X chromosome. We describe a case of a 40-year-old woman with a history of Type 2 diabetes mellitus, hyperlipidemia, and obesity, who presents with debilitating polyuria since the age of 5 with no clear diagnosis. Interestingly, her son was diagnosed with NDI. Genetic testing revealed that she was heterozygous for the Val88Met mutation in the AVPR2 gene while her son was hemizygous for the same. The patient has since been successfully treated with diuretics and a low solute diet. We highlight that although X-linked NDI patients are mostly males, it should be considered in symptomatic females to prevent delays in the diagnosis. Conformational diseases such as NDI are presently the subject of research using pharmacological chaperones to restore proper receptor membrane localization and function.

Coarse to fine aircraft detection from front-looking infrared images

Science.gov (United States)

Lin, Jin; Tan, Yihua; Tian, Jinwen

2018-03-01

Due to the weak feature and wide angle of long-distance aircraft targeting in the parking apron from front-looking infrared images, there are always false alarms in aircraft targeting detection. This leads to relatively poor reliability for detection results. In this paper, we present a scene-driven coarse-to-fine aircraft target detection method. First, we preprocess the image by combining the sharpened and enhanced images. Second, the region of interest (ROI) is segmented by using the local mean variance of the image and a series of subsequent processing. Then, target candidate areas are located by using the feature of local marginal distributions. Lastly, aircrafts can be detected accurately by a novel aircraft shape filter. Experiments on three infrared image sequences have shown that the presented method is effective and robust in detecting long-distance aircraft from front-looking infrared images and can also improve the reliability of the detection results.

76 FR 6525 - Airworthiness Directives; Cessna Aircraft Company (Type Certificate Previously Held by Columbia...

Science.gov (United States)

2011-02-07

... Airworthiness Directives; Cessna Aircraft Company (Type Certificate Previously Held by Columbia Aircraft... following new AD: 2011-03-04 Cessna Aircraft Company (Type Certificate Previously Held by Columbia Aircraft... the following Cessna Aircraft Company (type certificate previously held by Columbia Aircraft...

Improvement of Aircraft Crash Effective Areas for Koeberg Nuclear Power Plant

International Nuclear Information System (INIS)

Momoti, S.; Dongmo, G.B.; Combrink, Y.

2017-01-01

Probabilistic Safety Assessment (PSA): Tool for determining safe functioning of nuclear power plant to meet regulatory requirements; One of the inputs to the PSA are the frequency and consequences of an aircraft crash. Overview: Frequency of Aircraft Crash; Effective Area of an Aircraft Crashing into Koeberg - Aviation Categories, - Shielding of sensitive target buildings; Impact of refining the Effective AreaFrequency of Aircraft Crash

Volcanic Ash -Aircraft Encounter Damages: in Volcanological Point of View

Science.gov (United States)

Aydar, Erkan; Aladaǧ, Çaǧdaş Hakan; Menteş, Turhan

2017-04-01

The jet era or age began at 1930 and 40's in aviation sector, with the production of first jet engine for the aircrafts. Since 1950's, the commercial aviation with regular flights were established. Civil aviation and air-transport drastically increased due to intensive demand, and declared at least 10 fold since 1970 by IATA report. Parallelly to technological and economical developpement, the commercial jets became more comfortable, secure and rapid, bringing the world smaller, the countries closer. On the other hand, according to Global Volcanism Program Catalogues of Smithsonian Institute, about 1,500 volcanoes have erupted in the Holocene, 550 of them have had historical eruptions and considered as active. Besides an average of 55-60 volcanoes erupt each year, and about 8-10 of these eruptions produce ash clouds that reach aircraft flight altitudes (Salinas and Watt, 2004). Volcanic ash can be expected to be in air routes at altitudes greater than 9 km (30,000 ft) for roughly 20 days per year worldwide (Miller &Casadeval, 2000). A precious compilation of incidents due to encounters of aircrafts with volcanic ash clouds covering the years between 1953 and 2009 was used in this work (Guffanti et al., 2010-USGS Report) with an additional information on Eyfjallajökull-2010 eruption. According to this compilation,129 incidents happened within the concerned time interval. The damages, in general, fall in second and third class of Severity index, indicating the damages are limited on airframe of the planes, or some abrasions in jet engine, windblast etc.. We focused on fourth class of severity index involving the damages on jet engine of aircraft (engine fail) due to ingestion of volcanic ash and investigate eruption style and caused damage relationships. During the eruptive sequences of Mts Saint Helen (USA), Galunggung (Indonesia, 2 incidents), Redoubt (USA), Pinatubo (Philipinnes), Unzen (Japan), Manam (Papua New Guinea), Soufriere Hills (Lesser Antilles), Chaiten

Aircraft Fire Protection Laboratory

Data.gov (United States)

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

The Impact of Rising Temperatures on Aircraft Takeoff Performance

Science.gov (United States)

Coffel, E.; Horton, R. M.; Thompson, T. R.

2017-12-01

Steadily rising mean and extreme temperatures as a result of climate change will likely impact the air transportation system over the coming decades. As air temperatures rise at constant pressure, air density declines, resulting in less lift generation by an aircraft wing at a given airspeed and potentially imposing a weight restriction on departing aircraft. This study presents a general model to project future weight restrictions across a fleet of aircraft with different takeoff weights operating at a variety of airports. We construct performance models for five common commercial aircraft and 19 major airports around the world and use projections of daily temperatures from the CMIP5 model suite under the RCP 4.5 and RCP 8.5 emissions scenarios to calculate required hourly weight restriction. We find that on average, 10-30% of annual flights departing at the time of daily maximum temperature may require some weight restriction below their maximum takeoff weights, with mean restrictions ranging from 0.5 to 4% of total aircraft payload and fuel capacity by mid- to late century. Both mid-sized and large aircraft are affected, and airports with short runways and high tempera- tures, or those at high elevations, will see the largest impacts. Our results suggest that weight restriction may impose a non-trivial cost on airlines and impact aviation operations around the world and that adaptation may be required in aircraft design, airline schedules, and/or runway lengths.

Damage assessment of nuclear containment against aircraft crash

Energy Technology Data Exchange (ETDEWEB)

Iqbal, Mohd Ashraf, E-mail: iqbal_ashraf@rediffmail.com; Sadique, Md. Rehan, E-mail: rehan.sadique@gmail.com; Bhargava, Pradeep, E-mail: bhpdpfce@iitr.ac.in; Bhandari, N.M., E-mail: nmbcefce@iitr.ac.in

2014-10-15

Highlights: • Damage assessment of nuclear containment is studied against aircraft crash. • Four impact locations have been identified at the outer containment shell. • The mid of the total height has been found to be most vulnerable location. • The crown of dome has been found to be the strongest location. • Phantom F4 caused more localized and severe damage compared to other aircrafts. - Abstract: The behavior of nuclear containment structure has been studied against aircraft crash with an emphasis on the influence of strike location. The impact locations identified on the BWR Mark III type nuclear containment structure are mid-height, junction of dome and cylinder, crown of dome and arc of dome. The containment at each of the above locations has been impacted normally by Phantom F-4, Boeing 707-320 and Airbus A320 aircrafts. The loading of the aircraft has been assigned through the corresponding reaction-time response curve. ABAQUS/Explicit finite element code has been used to carry out the three-dimensional numerical simulations. The concrete damaged plasticity model was used to simulate the behavior of concrete while the behavior of steel reinforcement was incorporated using the Johnson–Cook elasto-viscoplastic material model. The mid-height of containment has been found to experience most severe deformation against each aircraft. Phantom F4 has been found to be most disastrous at each location. The results have been compared with those of the available studies with respect to the containment deformation.

75 FR 8427 - Civil Supersonic Aircraft Panel Discussion

Science.gov (United States)

2010-02-24

... entitled, ``State of the Art of Supersonics Aircraft Technology--What has progressed in science since 1973... DEPARTMENT OF TRANSPORTATION Federal Aviation Administration Civil Supersonic Aircraft Panel Discussion AGENCY: Federal Aviation Administration (FAA), DOT. ACTION: Notice of meeting participation...

Comprehensive analysis of transport aircraft flight performance

Science.gov (United States)

Filippone, Antonio

2008-04-01

This paper reviews the state-of-the art in comprehensive performance codes for fixed-wing aircraft. The importance of system analysis in flight performance is discussed. The paper highlights the role of aerodynamics, propulsion, flight mechanics, aeroacoustics, flight operation, numerical optimisation, stochastic methods and numerical analysis. The latter discipline is used to investigate the sensitivities of the sub-systems to uncertainties in critical state parameters or functional parameters. The paper discusses critically the data used for performance analysis, and the areas where progress is required. Comprehensive analysis codes can be used for mission fuel planning, envelope exploration, competition analysis, a wide variety of environmental studies, marketing analysis, aircraft certification and conceptual aircraft design. A comprehensive program that uses the multi-disciplinary approach for transport aircraft is presented. The model includes a geometry deck, a separate engine input deck with the main parameters, a database of engine performance from an independent simulation, and an operational deck. The comprehensive code has modules for deriving the geometry from bitmap files, an aerodynamics model for all flight conditions, a flight mechanics model for flight envelopes and mission analysis, an aircraft noise model and engine emissions. The model is validated at different levels. Validation of the aerodynamic model is done against the scale models DLR-F4 and F6. A general model analysis and flight envelope exploration are shown for the Boeing B-777-300 with GE-90 turbofan engines with intermediate passenger capacity (394 passengers in 2 classes). Validation of the flight model is done by sensitivity analysis on the wetted area (or profile drag), on the specific air range, the brake-release gross weight and the aircraft noise. A variety of results is shown, including specific air range charts, take-off weight-altitude charts, payload-range performance

Enabling alternate fuels for commercial aircraft

OpenAIRE

Daggett, D.

2010-01-01

The following reports on the past four years of work to examine the feasibility, sustainability and economic viability of developing a renewable, greenhouse-gas-neutral, liquid biofuel for commercial aircraft. The sharp increase in environmental concerns, such as global warming, as well as the volatile price fluctuations of fossil fuels, has ignited a search for alternative transportation fuels. However, commercial aircraft can not use present alternative fuels that are designed for ground...

Aircraft gas turbine engine vibration diagnostics

OpenAIRE

Stanislav Fábry; Marek Češkovič

2017-01-01

In the Czech and Slovak aviation are in service elderly aircrafts, usually produced in former Soviet Union. Their power units can be operated in more efficient way, in case of using additional diagnostic methods that allow evaluating their health. Vibration diagnostics is one of the methods indicating changes of rotational machine dynamics. Ground tests of aircraft gas turbine engines allow vibration recording and analysis. Results contribute to airworthiness evaluation and making corrections...

Congestion Pricing for Aircraft Pushback Slot Allocation

Science.gov (United States)

Zhang, Yaping

2017-01-01

In order to optimize aircraft pushback management during rush hour, aircraft pushback slot allocation based on congestion pricing is explored while considering monetary compensation based on the quality of the surface operations. First, the concept of the “external cost of surface congestion” is proposed, and a quantitative study on the external cost is performed. Then, an aircraft pushback slot allocation model for minimizing the total surface cost is established. An improved discrete differential evolution algorithm is also designed. Finally, a simulation is performed on Xinzheng International Airport using the proposed model. By comparing the pushback slot control strategy based on congestion pricing with other strategies, the advantages of the proposed model and algorithm are highlighted. In addition to reducing delays and optimizing the delay distribution, the model and algorithm are better suited for use for actual aircraft pushback management during rush hour. Further, it is also observed they do not result in significant increases in the surface cost. These results confirm the effectiveness and suitability of the proposed model and algorithm. PMID:28114429

Congestion Pricing for Aircraft Pushback Slot Allocation.

Science.gov (United States)

Liu, Lihua; Zhang, Yaping; Liu, Lan; Xing, Zhiwei

2017-01-01

In order to optimize aircraft pushback management during rush hour, aircraft pushback slot allocation based on congestion pricing is explored while considering monetary compensation based on the quality of the surface operations. First, the concept of the "external cost of surface congestion" is proposed, and a quantitative study on the external cost is performed. Then, an aircraft pushback slot allocation model for minimizing the total surface cost is established. An improved discrete differential evolution algorithm is also designed. Finally, a simulation is performed on Xinzheng International Airport using the proposed model. By comparing the pushback slot control strategy based on congestion pricing with other strategies, the advantages of the proposed model and algorithm are highlighted. In addition to reducing delays and optimizing the delay distribution, the model and algorithm are better suited for use for actual aircraft pushback management during rush hour. Further, it is also observed they do not result in significant increases in the surface cost. These results confirm the effectiveness and suitability of the proposed model and algorithm.

Congestion Pricing for Aircraft Pushback Slot Allocation.

Directory of Open Access Journals (Sweden)

Lihua Liu

Full Text Available In order to optimize aircraft pushback management during rush hour, aircraft pushback slot allocation based on congestion pricing is explored while considering monetary compensation based on the quality of the surface operations. First, the concept of the "external cost of surface congestion" is proposed, and a quantitative study on the external cost is performed. Then, an aircraft pushback slot allocation model for minimizing the total surface cost is established. An improved discrete differential evolution algorithm is also designed. Finally, a simulation is performed on Xinzheng International Airport using the proposed model. By comparing the pushback slot control strategy based on congestion pricing with other strategies, the advantages of the proposed model and algorithm are highlighted. In addition to reducing delays and optimizing the delay distribution, the model and algorithm are better suited for use for actual aircraft pushback management during rush hour. Further, it is also observed they do not result in significant increases in the surface cost. These results confirm the effectiveness and suitability of the proposed model and algorithm.

Probabilistic assessment of NPP safety under aircraft impact

International Nuclear Information System (INIS)

Birbraer, A.N.; Roleder, A.J.; Arhipov, S.B.

1999-01-01

Methodology of probabilistic assessment of NPP safety under aircraft impact is described below. The assessment is made taking into account not only the fact of aircraft fall onto the NPP building, but another casual parameters too, namely an aircraft class, velocity and mass, as well as point and angle of its impact with the building structure. This analysis can permit to justify the decrease of the required structure strength and dynamic loads on the NPP equipment. It can also be especially useful when assessing the safety of existing NPP. (author)

Review of Idealized Aircraft Wake Vortex Models

Science.gov (United States)

Ahmad, Nashat N.; Proctor, Fred H.; Duparcmeur, Fanny M. Limon; Jacob, Don

2014-01-01

Properties of three aircraft wake vortex models, Lamb-Oseen, Burnham-Hallock, and Proctor are reviewed. These idealized models are often used to initialize the aircraft wake vortex pair in large eddy simulations and in wake encounter hazard models, as well as to define matched filters for processing lidar observations of aircraft wake vortices. Basic parameters for each vortex model, such as peak tangential velocity and circulation strength as a function of vortex core radius size, are examined. The models are also compared using different vortex characterizations, such as the vorticity magnitude. Results of Euler and large eddy simulations are presented. The application of vortex models in the postprocessing of lidar observations is discussed.

Inerting Aircraft Fuel Systems Using Exhaust Gases

Science.gov (United States)

Hehemann, David G.

2002-01-01

Our purpose in this proposal was to determine the feasibility of using carbon dioxide, possibly obtained from aircraft exhaust gases as a substance to inert the fuel contained in fuel tanks aboard aircraft. To do this, we decided to look at the effects carbon dioxide has upon commercial Jet-A aircraft fuel. In particular, we looked at the solubility of CO2 in Jet-A fuel, the pumpability of CO2-saturated Jet-A fuel, the flashpoint of Jet-A fuel under various mixtures of air and CO2, the static outgassing of CO2-Saturated Jet-A fuel and the dynamic outgassing of Jet-A fuel during pumping of Jet-A fuel.

Management of diabetes insipidus in children

Science.gov (United States)

Mishra, Garima; Chandrashekhar, Sudha Rao

2011-01-01

Diabetes Insipidus (DI) is a heterogeneous clinical syndrome of disturbance in water balance, characterized by polyuria (urine output > 4 ml/kg/hr), polydypsia (water intake > 2 L/m2/d) and failure to thrive. In children, Nephrogenic DI (NDI) is more common than Central DI (CDI), and is often acquired. The signs and symptoms vary with etiology, age at presentation and mode of onset. Neonates and infants with NDI are severely affected and difficult to treat. Diagnosis is based on the presence of high plasma osmolality and low urinary osmolality with significant water diuresis. Water deprivation test with vasopressin challenge, though has limitations, is done to differentiate NDI and CDI and diagnose their partial forms. Measurement of urinary aquaporin 2 and serum copeptin levels are being studied and show promising diagnostic potential. Magnetic Resonance Imaging (MRI) pituitary helps in the etiological diagnosis of CDI, absence of posterior pituitary bright signal being the pathognomic sign. If pituitary stalk thickening of < 2 mm is present, these children need to be monitored for evolving lesion. Neonates and young infants are better managed with fluids alone. Older children with CDI are treated with desmopressin. The oral form is safe, highly effective, with more flexibility of dosing and has largely replaced the intranasal form. In NDI besides treatment of the underlying cause, use of high calorie low solute diet and drugs to ameliorate water excretion (thiazide, amelioride, indomethacin) are useful. Children with NDI however well treated, remain short and have mental retardation on follow up. PMID:22029022

Management of diabetes insipidus in children

Directory of Open Access Journals (Sweden)

Garima Mishra

2011-01-01

Full Text Available Diabetes Insipidus (DI is a heterogeneous clinical syndrome of disturbance in water balance, characterized by polyuria (urine output > 4 ml/kg/hr, polydypsia (water intake > 2 L/m 2 /d and failure to thrive. In children, Nephrogenic DI (NDI is more common than Central DI (CDI, and is often acquired. The signs and symptoms vary with etiology, age at presentation and mode of onset. Neonates and infants with NDI are severely affected and difficult to treat. Diagnosis is based on the presence of high plasma osmolality and low urinary osmolality with significant water diuresis. Water deprivation test with vasopressin challenge, though has limitations, is done to differentiate NDI and CDI and diagnose their partial forms. Measurement of urinary aquaporin 2 and serum copeptin levels are being studied and show promising diagnostic potential. Magnetic Resonance Imaging (MRI pituitary helps in the etiological diagnosis of CDI, absence of posterior pituitary bright signal being the pathognomic sign. If pituitary stalk thickening of < 2 mm is present, these children need to be monitored for evolving lesion. Neonates and young infants are better managed with fluids alone. Older children with CDI are treated with desmopressin. The oral form is safe, highly effective, with more flexibility of dosing and has largely replaced the intranasal form. In NDI besides treatment of the underlying cause, use of high calorie low solute diet and drugs to ameliorate water excretion (thiazide, amelioride, indomethacin are useful. Children with NDI however well treated, remain short and have mental retardation on follow up.

26 x 6.6 radial-belted aircraft tire performance

Science.gov (United States)

Davis, Pamela A.; Martinson, Veloria J.; Yager, Thomas J.; Stubbs, Sandy M.

1991-01-01

Preliminary results from testing of 26 x 6.6 radial-belted and bias-ply aircraft tires at NASA Langley's Aircraft Landing Dynamics Facility (ALDF) are reviewed. The 26 x 6.6 tire size evaluation includes cornering performance tests throughout the aircraft ground operational speed range for both dry and wet runway surfaces. Static test results to define 26 x 6.6 tire vertical stiffness properties are also presented and discussed.

77 FR 33083 - Airworthiness Directives; WACO Classic Aircraft Corporation Airplanes

Science.gov (United States)

2012-06-05

... Airworthiness Directives; WACO Classic Aircraft Corporation Airplanes AGENCY: Federal Aviation Administration... directive (AD) for certain WACO Classic Aircraft Corporation Models 2T-1A, 2T-1A-1, and 2T-1A-2 airplanes... information identified in this AD, contact WACO Classic Aircraft Corporation; 15955 South Airport Rd., Battle...

Copycats in Pilot Aircraft-Assisted Suicides after the Germanwings Incident

Directory of Open Access Journals (Sweden)

Tanja Laukkala

2018-03-01

Full Text Available Aircraft-assisted pilot suicide is a rare but serious phenomenon. The aim of this study was to evaluate changes in pilot aircraft-assisted suicide risks, i.e., a copycat effect, in the U.S. and Germany after the Germanwings 2015 incident in the French Alps. Aircraft-assisted pilot suicides were searched in the U.S. National Transportation Safety Board (NTSB accident investigation database and in the German Bundestelle für Flugunfalluntersuchung (BFU Reports of Investigation database five years before and two years after the deliberate crash of the Germanwings flight into the French Alps in 2015. The relative risk (RR of the aircraft-assisted pilot suicides was calculated. Two years after the incident, three out of 454 (0.66% fatal incidents were aircraft-assisted suicides compared with six out of 1292 (0.46% in the prior five years in the NTSB database. There were no aircraft-assisted pilot suicides in the German database during the two years after or five years prior to the Germanwings crash. The relative aircraft-assisted pilot suicide risk for the U.S. was 1.4 (95% CI 0.3–4.2 which was not statistically significant. Six of the pilots who died by suicide had told someone of their suicidal intentions. We consider changes in the rate to be within a normal variation. Responsible media coverage of aircraft incidents is important due to the large amount of publicity that these events attract.

Copycats in Pilot Aircraft-Assisted Suicides after the Germanwings Incident

Science.gov (United States)

Vuorio, Alpo; Bor, Robert; Budowle, Bruce; Navathe, Pooshan; Pukkala, Eero; Sajantila, Antti

2018-01-01

Aircraft-assisted pilot suicide is a rare but serious phenomenon. The aim of this study was to evaluate changes in pilot aircraft-assisted suicide risks, i.e., a copycat effect, in the U.S. and Germany after the Germanwings 2015 incident in the French Alps. Aircraft-assisted pilot suicides were searched in the U.S. National Transportation Safety Board (NTSB) accident investigation database and in the German Bundestelle für Flugunfalluntersuchung (BFU) Reports of Investigation database five years before and two years after the deliberate crash of the Germanwings flight into the French Alps in 2015. The relative risk (RR) of the aircraft-assisted pilot suicides was calculated. Two years after the incident, three out of 454 (0.66%) fatal incidents were aircraft-assisted suicides compared with six out of 1292 (0.46%) in the prior five years in the NTSB database. There were no aircraft-assisted pilot suicides in the German database during the two years after or five years prior to the Germanwings crash. The relative aircraft-assisted pilot suicide risk for the U.S. was 1.4 (95% CI 0.3–4.2) which was not statistically significant. Six of the pilots who died by suicide had told someone of their suicidal intentions. We consider changes in the rate to be within a normal variation. Responsible media coverage of aircraft incidents is important due to the large amount of publicity that these events attract. PMID:29534475

Aircraft family design using enhanced collaborative optimization

Science.gov (United States)

Roth, Brian Douglas

Significant progress has been made toward the development of multidisciplinary design optimization (MDO) methods that are well-suited to practical large-scale design problems. However, opportunities exist for further progress. This thesis describes the development of enhanced collaborative optimization (ECO), a new decomposition-based MDO method. To support the development effort, the thesis offers a detailed comparison of two existing MDO methods: collaborative optimization (CO) and analytical target cascading (ATC). This aids in clarifying their function and capabilities, and it provides inspiration for the development of ECO. The ECO method offers several significant contributions. First, it enhances communication between disciplinary design teams while retaining the low-order coupling between them. Second, it provides disciplinary design teams with more authority over the design process. Third, it resolves several troubling computational inefficiencies that are associated with CO. As a result, ECO provides significant computational savings (relative to CO) for the test cases and practical design problems described in this thesis. New aircraft development projects seldom focus on a single set of mission requirements. Rather, a family of aircraft is designed, with each family member tailored to a different set of requirements. This thesis illustrates the application of decomposition-based MDO methods to aircraft family design. This represents a new application area, since MDO methods have traditionally been applied to multidisciplinary problems. ECO offers aircraft family design the same benefits that it affords to multidisciplinary design problems. Namely, it simplifies analysis integration, it provides a means to manage problem complexity, and it enables concurrent design of all family members. In support of aircraft family design, this thesis introduces a new wing structural model with sufficient fidelity to capture the tradeoffs associated with component

Analysis of Automated Aircraft Conflict Resolution and Weather Avoidance

Science.gov (United States)

Love, John F.; Chan, William N.; Lee, Chu Han

2009-01-01

This paper describes an analysis of using trajectory-based automation to resolve both aircraft and weather constraints for near-term air traffic management decision making. The auto resolution algorithm developed and tested at NASA-Ames to resolve aircraft to aircraft conflicts has been modified to mitigate convective weather constraints. Modifications include adding information about the size of a gap between weather constraints to the routing solution. Routes that traverse gaps that are smaller than a specific size are not used. An evaluation of the performance of the modified autoresolver to resolve both conflicts with aircraft and weather was performed. Integration with the Center-TRACON Traffic Management System was completed to evaluate the effect of weather routing on schedule delays.

Parameterized Flight Mission for Secondary Power Requirement Estimations of Commercial Transport Aircraft

OpenAIRE

Lampl, Thomas; Muschkorgel, Sandra; Hornung, Mirko;

2018-01-01

The trend towards More-Electric Aircraft (MEA) and the introduction of new system technologies lead to considerable changes at the system level of commercial transport aircraft. Because the number of systems and power requirements are increasing, the consideration and integration of aircraft systems in early aircraft design phases is important. The objective of this contribution is to develop a characteristic flight mission with modelled aircraft systems to estimate the secondary power requir...

Aircraft parameter estimation

Indian Academy of Sciences (India)

With the evolution of high performance modern aircraft and spiraling developmental and experimental costs, the importance of flight validated databases for flight control design applications and for flight simulators has increased significantly in the recent past. Ground-based and in-flight simulators are increasingly used not ...

Corrosion Sensor Development for Condition-Based Maintenance of Aircraft

Directory of Open Access Journals (Sweden)

Gino Rinaldi

2012-01-01

Full Text Available Aircraft routinely operate in atmospheric environments that, over time, will impact their structural integrity. Material protection and selection schemes notwithstanding, recurrent exposure to chlorides, pollution, temperature gradients, and moisture provide the necessary electrochemical conditions for the development and profusion of corrosion in aircraft structures. For aircraft operators, this becomes an important safety matter as corrosion found in a given aircraft must be assumed to be present in all of that type of aircraft. This safety protocol and its associated unscheduled maintenance requirement drive up the operational costs of the fleet and limit the availability of the aircraft. Hence, there is an opportunity at present for developing novel sensing technologies and schemes to aid in shifting time-based maintenance schedules towards condition-based maintenance procedures. In this work, part of the ongoing development of a multiparameter integrated corrosion sensor is presented. It consists of carbon nanotube/polyaniline polymer sensors and commercial-off-the-shelf sensors. It is being developed primarily for monitoring environmental and material factors for the purpose of providing a means to more accurately assess the structural integrity of aerospace aluminium alloys through fusion of multiparameter sensor data. Preliminary experimental test results are presented for chloride ion concentration, hydrogen gas evolution, humidity variations, and material degradation.

Improving aircraft accident forecasting for an integrated plutonium storage facility

International Nuclear Information System (INIS)

Rock, J.C.; Kiffe, J.; McNerney, M.T.; Turen, T.A.

1998-06-01

Aircraft accidents pose a quantifiable threat to facilities used to store and process surplus weapon-grade plutonium. The Department of Energy (DOE) recently published its first aircraft accident analysis guidelines: Accident Analysis for Aircraft Crash into Hazardous Facilities. This document establishes a hierarchy of procedures for estimating the small annual frequency for aircraft accidents that impact Pantex facilities and the even smaller frequency of hazardous material released to the environment. The standard establishes a screening threshold of 10 -6 impacts per year; if the initial estimate of impact frequency for a facility is below this level, no further analysis is required. The Pantex Site-Wide Environmental Impact Statement (SWEIS) calculates the aircraft impact frequency to be above this screening level. The DOE Standard encourages more detailed analyses in such cases. This report presents three refinements, namely, removing retired small military aircraft from the accident rate database, correcting the conversion factor from military accident rates (accidents per 100,000 hours) to the rates used in the DOE model (accidents per flight phase), and adjusting the conditional probability of impact for general aviation to more accurately reflect pilot training and local conditions. This report documents a halving of the predicted frequency of an aircraft impact at Pantex and points toward further reductions

49 CFR 173.172 - Aircraft hydraulic power unit fuel tank.

Science.gov (United States)

2010-10-01

... 49 Transportation 2 2010-10-01 2010-10-01 false Aircraft hydraulic power unit fuel tank. 173.172... Class 1 and Class 7 § 173.172 Aircraft hydraulic power unit fuel tank. Aircraft hydraulic power unit fuel tanks containing a mixture of anhydrous hydrazine and monomethyl hydrazine (M86 fuel) and designed...

X-36 Tailless Fighter Agility Research Aircraft in flight

Science.gov (United States)

1997-01-01

The lack of a vertical tail on the X-36 technology demonstrator is evident as the remotely piloted aircraft flies a low-altitude research flight above Rogers Dry Lake at Edwards Air Force Base in the California desert on October 30, 1997. The NASA/Boeing X-36 Tailless Fighter Agility Research Aircraft program successfully demonstrated the tailless fighter design using advanced technologies to improve the maneuverability and survivability of possible future fighter aircraft. The program met or exceeded all project goals. For 31 flights during 1997 at the Dryden Flight Research Center, Edwards, California, the project team examined the aircraft's agility at low speed / high angles of attack and at high speed / low angles of attack. The aircraft's speed envelope reached up to 206 knots (234 mph). This aircraft was very stable and maneuverable. It handled very well. The X-36 vehicle was designed to fly without the traditional tail surfaces common on most aircraft. Instead, a canard forward of the wing was used as well as split ailerons and an advanced thrust-vectoring nozzle for directional control. The X-36 was unstable in both pitch and yaw axes, so an advanced, single-channel digital fly-by-wire control system (developed with some commercially available components) was put in place to stabilize the aircraft. Using a video camera mounted in the nose of the aircraft and an onboard microphone, the X-36 was remotely controlled by a pilot in a ground station virtual cockpit. A standard fighter-type head-up display (HUD) and a moving-map representation of the vehicle's position within the range in which it flew provided excellent situational awareness for the pilot. This pilot-in-the-loop approach eliminated the need for expensive and complex autonomous flight control systems and the risks associated with their inability to deal with unknown or unforeseen phenomena in flight. Fully fueled the X-36 prototype weighed approximately 1,250 pounds. It was 19 feet long and three

Optimised Sound Absorbing Trim Panels for the Reduction of Aircraft Cabin Noise

NARCIS (Netherlands)

Hannink, M.H.C.; Wijnant, Ysbrand H.; de Boer, Andries; Ivanov, N.I.; Crocker, M.J.

2004-01-01

The EU project FACE (Friendly Aircraft Cabin Environment) aims to improve the environmental comfort in aircraft cabins. As part of this project, this paper focuses on the reduction of noise in aircraft cabins. For modern aircraft flying at cruise conditions, this cabin noise is known to be dominated

Wide Body Aircraft Demand Potential at Washington National Airport,

Science.gov (United States)

1977-09-01

the city-pair markets. Probably the most important feature of FA-7 is the fact that it allows for investigation of the behavior of airlines to changes...FINANCIAL INFORMfATION YLIGHTS BY AIRCRAFT TPE ~.4/J \\ FUEL COSUMED PASSENGERS UARRIED BY TOA IR F FLIGHITS TOTAL AIRCRAFT USAGE coded data. Sample...the various levels of operations. Similar behavior can be identified in the simultaneous increase of both types of aircraft at Dulles. Tables lAthrough

Reduction environmental effects of civil aircraft through multi-objective flight plan optimisation

International Nuclear Information System (INIS)

Lee, D S; Gonzalez, L F; Walker, R; Periaux, J; Onate, E

2010-01-01

With rising environmental alarm, the reduction of critical aircraft emissions including carbon dioxides (CO 2 ) and nitrogen oxides (NO x ) is one of most important aeronautical problems. There can be many possible attempts to solve such problem by designing new wing/aircraft shape, new efficient engine, etc. The paper rather provides a set of acceptable flight plans as a first step besides replacing current aircrafts. The paper investigates a green aircraft design optimisation in terms of aircraft range, mission fuel weight (CO 2 ) and NO x using advanced Evolutionary Algorithms coupled to flight optimisation system software. Two multi-objective design optimisations are conducted to find the best set of flight plans for current aircrafts considering discretised altitude and Mach numbers without designing aircraft shape and engine types. The objectives of first optimisation are to maximise range of aircraft while minimising NO x with constant mission fuel weight. The second optimisation considers minimisation of mission fuel weight and NO x with fixed aircraft range. Numerical results show that the method is able to capture a set of useful trade-offs that reduce NO x and CO 2 (minimum mission fuel weight).

Aircraft operability methods applied to space launch vehicles

Science.gov (United States)

Young, Douglas

1997-01-01

The commercial space launch market requirement for low vehicle operations costs necessitates the application of methods and technologies developed and proven for complex aircraft systems. The ``building in'' of reliability and maintainability, which is applied extensively in the aircraft industry, has yet to be applied to the maximum extent possible on launch vehicles. Use of vehicle system and structural health monitoring, automated ground systems and diagnostic design methods derived from aircraft applications support the goal of achieving low cost launch vehicle operations. Transforming these operability techniques to space applications where diagnostic effectiveness has significantly different metrics is critical to the success of future launch systems. These concepts will be discussed with reference to broad launch vehicle applicability. Lessons learned and techniques used in the adaptation of these methods will be outlined drawing from recent aircraft programs and implementation on phase 1 of the X-33/RLV technology development program.

Evaluation of all-electric secondary power for transport aircraft

Science.gov (United States)

Murray, W. E.; Feiner, L. J.; Flores, R. R.

1992-01-01

This report covers a study by Douglas Aircraft Company (DAC) of electrical power systems for advanced transport aircraft based upon an all-electric design concept. The concept would eliminate distributed hydraulic and pneumatic secondary power systems, and feature an expanded secondary electrical power system redesigned to supply power to the loads customarily supplied by hydraulic or pneumatic power. The initial study was based on an advanced 20-kHz electrical power transmission and distribution system, using a system architecture supplied by NASA-Lewis Research Center for twin-engine aircraft with many advanced power conversion concepts. NASA-LeRC later requested DAC to refocus the study on 400-Hz secondary power distribution. Subsequent work was based on a three-engine MD-11 aircraft, selected by DAC as a baseline system design that would provide data for the comparative cost/benefit analysis. The study concluded that the 20-kHz concept produced many expected benefits, and that the all-electric trijet weight savings on hardware redesign would be 2,304 pounds plus a 2.1-percent fuel reduction and resized for a total weight reduction of 11,000 pounds. Cost reductions for a fleet of 800 aircraft in a 15-year production program were estimated at $76.71 million for RDT&E; $2.74 million per aircrat for production; $9.84 million for nonrecurring expenses; $120,000 per aircraft for product support; and $300,000 per aircraft per year for operating and maintenance costs, giving a present value of $1.914 billion saved or a future value of $10.496 billion saved.

A design for KLM Aircraft Services' Planning-rostering indeling chain

NARCIS (Netherlands)

Dekkers, K J.P.

2010-01-01

This report describes a Logistics Management Systems design project that is performed at KLM Aircraft Services (AS). AS is the part of KLM that is responsible for a large portion of the tasks that must be done to an aircraft that has landed and has to be used again. When an aircraft has landed the

48 CFR 1352.228-74 - Fair market value of aircraft.

Science.gov (United States)

2010-10-01

... 48 Federal Acquisition Regulations System 5 2010-10-01 2010-10-01 false Fair market value of... Fair market value of aircraft. As prescribed in 48 CFR 1328.310-70(e) and 48 CFR 1328.310-70(g) insert the following in all applicable contracts for leased aircraft: Fair Market Value of Aircraft (APR 2010...

Aircraft noise: effects on macro- and microstructure of sleep.

Science.gov (United States)

Basner, Mathias; Glatz, Christian; Griefahn, Barbara; Penzel, Thomas; Samel, Alexander

2008-05-01

The effects of aircraft noise on sleep macrostructure (Rechtschaffen and Kales) and microstructure (American Sleep Disorders Association [ASDA] arousal criteria) were investigated. For each of 10 subjects (mean age 35.3 years, 5 males), a baseline night without aircraft noise (control), and two nights with exposure to 64 noise events with a maximum sound pressure level (SPL) of either 45 or 65 dBA were chosen. Spontaneous and noise-induced alterations during sleep classified as arousals (ARS), changes to lighter sleep stages (CSS), awakenings including changes to sleep stage 1 (AS1), and awakenings (AWR) were analyzed. The number of events per night increased in the order AWR, AS1, CSS, and ARS under control conditions as well as under the two noise conditions. Furthermore, probabilities for sleep disruptions increased with increasing noise level. ARS were observed about fourfold compared to AWR, irrespective of control or noise condition. Under the conditions investigated, different sleep parameters show different sensitivities, but also different specificities for noise-induced sleep disturbances. We conclude that most information on sleep disturbances can be achieved by investigating robust classic parameters like AWR or AS1, although ASDA electroencephalographic (EEG) arousals might add relevant information in situations with low maximum SPLs, chronic sleep deprivation or chronic exposure.

Practical Voice Recognition for the Aircraft Cockpit, Phase I

Data.gov (United States)

National Aeronautics and Space Administration — This proposal responds to the urgent need for improved pilot interfaces in the modern aircraft cockpit. Recent advances in aircraft equipment bring tremendous...

Personality Test Scores that Distinguish U.S. Air Force Remotely Piloted Aircraft Drone Pilot Training Candidates

Science.gov (United States)

2014-02-18

advancement of aviation drone technology has led to significant developments and improvements in the capabilities of military remotely piloted aircraft...stress; less excitement seeking and action oriented; less assertive; more socially introverted and withdrawn; more socially compliant and...to age and educational differences. Fifth, evaluations that involve selection and assessment of pilot applicants should include collateral sources of

Aircraft operational reliability—A model-based approach and a case study

International Nuclear Information System (INIS)

Tiassou, Kossi; Kanoun, Karama; Kaâniche, Mohamed; Seguin, Christel; Papadopoulos, Chris

2013-01-01

The success of an aircraft mission is subject to the fulfillment of some operational requirements before and during each flight. As these requirements depend essentially on the aircraft system components and the mission profile, the effects of failures can be very severe if they are not anticipated. Hence, one should be able to assess the aircraft operational reliability with regard to its missions in order to be able to cope with failures. We address aircraft operational reliability modeling to support maintenance planning during the mission achievement. We develop a modeling approach, based on a meta-model that is used as a basis: (i) to structure the information needed to assess aircraft operational reliability and (ii) to build a stochastic model that can be tuned dynamically, in order to take into account the aircraft system operational state, a mission profile and the maintenance facilities available at the flight stop locations involved in the mission. The aim is to enable operational reliability assessment online. A case study, based on an aircraft subsystem, is considered for illustration using the Stochastic Activity Networks (SANs) formalism

Aircraft Segmentation in SAR Images Based on Improved Active Shape Model

Science.gov (United States)

Zhang, X.; Xiong, B.; Kuang, G.

2018-04-01

In SAR image interpretation, aircrafts are the important targets arousing much attention. However, it is far from easy to segment an aircraft from the background completely and precisely in SAR images. Because of the complex structure, different kinds of electromagnetic scattering take place on the aircraft surfaces. As a result, aircraft targets usually appear to be inhomogeneous and disconnected. It is a good idea to extract an aircraft target by the active shape model (ASM), since combination of the geometric information controls variations of the shape during the contour evolution. However, linear dimensionality reduction, used in classic ACM, makes the model rigid. It brings much trouble to segment different types of aircrafts. Aiming at this problem, an improved ACM based on ISOMAP is proposed in this paper. ISOMAP algorithm is used to extract the shape information of the training set and make the model flexible enough to deal with different aircrafts. The experiments based on real SAR data shows that the proposed method achieves obvious improvement in accuracy.

78 FR 35085 - Consensus Standards, Light-Sport Aircraft

Science.gov (United States)

2013-06-11

... DEPARTMENT OF TRANSPORTATION Federal Aviation Administration Consensus Standards, Light-Sport... to the provisions of the Sport Pilot and Light-Sport Aircraft rule issued July 16, 2004, and effective September 1, 2004. ASTM International Committee F37 on Light Sport Aircraft developed the new and...

77 FR 24251 - Consensus Standards, Light-Sport Aircraft

Science.gov (United States)

2012-04-23

... DEPARTMENT OF TRANSPORTATION Federal Aviation Administration Consensus Standards, Light-Sport... relating to the provisions of the Sport Pilot and Light-Sport Aircraft rule issued July 16, 2004, and effective September 1, 2004. ASTM International Committee F37 on Light Sport Aircraft developed the new and...

Alternate aircraft fuels: Prospects and operational implications

Science.gov (United States)

Witcofski, R. D.

1977-01-01

The potential use of coal-derived aviation fuels was assessed. The studies addressed the prices and thermal efficiencies associated with the production of coal-derived aviation kerosene, liquid methane and liquid hydrogen and the air terminal requirements and subsonic transport performance when utilizing liquid hydrogen. The fuel production studies indicated that liquid methane can be produced at a lower price and with a higher thermal efficiency than aviation kerosene or liquid hydrogen. Ground facilities of liquefaction, storage, distribution and refueling of liquid hydrogen fueled aircraft at airports appear technically feasibile. The aircraft studies indicate modest onboard energy savings for hydrogen compared to conventional fuels. Liquid hydrogen was found to be superior to both aviation kerosene and liquid methane from the standpoint of aircraft engine emissions.

On using PEMFC for Electrical Power Generation on More Electric Aircraft

OpenAIRE

Jenica Ileana Corcau; Liviu Dinca

2012-01-01

The electrical power systems of aircrafts have made serious progress in recent years because the aircrafts depend more and more on the electricity. There is a trend in the aircraft industry to replace hydraulic and pneumatic systems with electrical systems, achieving more comfort and monitoring features and enlarging the energetic efficiency. Thus, was born the concept More Electric Aircraft. In this paper is analyzed the integration of a fuel cell into the existing elect...

Generic regional aircraft flying qualities for the approach and landing task

OpenAIRE

Gautrey, Jim

1997-01-01

Many changes have occurred in the past 20 years in aircraft manufacture and development. New technologies have appeared, spanning the entire aircraft design environment, such as new production methods, new materials and new avionics systems. These new methods have been developed for two reasons. For military aircraft, they have arisen through the need to improve performance. However, for civil aircraft they have arisen through the need to reduce the overall cost. This report co...

Aircraft Electric Propulsion Systems Applied Research at NASA

Science.gov (United States)

Clarke, Sean

2015-01-01

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.

Status report on the land processes aircraft science management operations working group

Science.gov (United States)

Lawless, James G.; Mann, Lisa J.

1991-01-01

Since its inception three years ago, the Land Processes Aircraft Science Management Operations Working Group (MOWG) provided recommendations on the optimal use of the Agency's aircraft in support of the Land Processes Science Program. Recommendations covered topics such as aircraft and sensor usage, development of long-range plans, Multisensor Airborne Campaigns (MAC), program balance, aircraft sensor databases, new technology and sensor development, and increased University scientist participation in the program. Impacts of these recommendations improved the efficiency of various procedures including the flight request process, tracking of flight hours, and aircraft usage. The group also created a bibliography focused on publications produced by Land Processes scientists from the use of the aircraft program, surveyed NASA funded PI's on their participation in the aircraft program, and developed a planning template for multi-sensor airborne campaigns. Benefits from these activities are summarized.

Bacteria that Travel: The Quality of Aircraft Water

Directory of Open Access Journals (Sweden)

Harald Handschuh

2015-10-01

Full Text Available The travelling population is increasing globally year on year. International tourist arrival figures reached 1087 million in 2013 and 1133 million in 2014; of which 53% and 54% respectively accounted for air transport. The water on board aircraft is sourced from surface or ground water; piped to a central filling point and distributed to each aircraft by water service vehicles at the home base or at the destination airport. The purpose of this study was to ascertain the microbial, chemical (pH; Total and Free chlorine and physical (temperature quality of water from two aircraft, long- and short-haul, as well as from the original water source and the water service vehicle. A total of 154 water samples were collected and analysed. Long-haul flights were found to be significantly poorer in terms of microbial quality than short haul flights (p = 0.015. Furthermore, correlation and regression analysis showed that the water service vehicle was a significant source of increased microbial load in aircraft. Microbial diversity was also demonstrated, with 37 bacterial species identified belonging to eight classes: γ-Proteobacteria; β-Proteobacteria; α-Proteobacteria; Bacilli; Actinobacteria; Flavobacteria; Sphingobacteria and Cytophaga; using phenotypic and 16S rDNA sequence-based analysis. We present a novel quantified study of aircraft-related potable water supplies.

Probabilistic Modeling of Aircraft Trajectories for Dynamic Separation Volumes

Science.gov (United States)

Lewis, Timothy A.

2016-01-01

With a proliferation of new and unconventional vehicles and operations expected in the future, the ab initio airspace design will require new approaches to trajectory prediction for separation assurance and other air traffic management functions. This paper presents an approach to probabilistic modeling of the trajectory of an aircraft when its intent is unknown. The approach uses a set of feature functions to constrain a maximum entropy probability distribution based on a set of observed aircraft trajectories. This model can be used to sample new aircraft trajectories to form an ensemble reflecting the variability in an aircraft's intent. The model learning process ensures that the variability in this ensemble reflects the behavior observed in the original data set. Computational examples are presented.

Aurora Flight Sciences' Perseus B Remotely Piloted Aircraft in Flight

Science.gov (United States)

1998-01-01

A long, slender wing and a pusher propeller at the rear characterize the Perseus B remotely piloted research aircraft, seen here during a test flight in June 1998. Perseus B is a remotely piloted aircraft developed as a design-performance testbed under NASA's Environmental Research Aircraft and Sensor Technology (ERAST) project. Perseus is one of several flight vehicles involved in the ERAST project. A piston engine, propeller-powered aircraft, Perseus was designed and built by Aurora Flight Sciences Corporation, Manassas, Virginia. The objectives of Perseus B's ERAST flight tests have been to reach and maintain horizontal flight above altitudes of 60,000 feet and demonstrate the capability to fly missions lasting from 8 to 24 hours, depending on payload and altitude requirements. The Perseus B aircraft established an unofficial altitude record for a single-engine, propeller-driven, remotely piloted aircraft on June 27, 1998. It reached an altitude of 60,280 feet. In 1999, several modifications were made to the Perseus aircraft including engine, avionics, and flight-control-system improvements. These improvements were evaluated in a series of operational readiness and test missions at the Dryden Flight Research Center, Edwards, California. Perseus is a high-wing monoplane with a conventional tail design. Its narrow, straight, high-aspect-ratio wing is mounted atop the fuselage. The aircraft is pusher-designed with the propeller mounted in the rear. This design allows for interchangeable scientific-instrument payloads to be placed in the forward fuselage. The design also allows for unobstructed airflow to the sensors and other devices mounted in the payload compartment. The Perseus B that underwent test and development in 1999 was the third generation of the Perseus design, which began with the Perseus Proof-Of-Concept aircraft. Perseus was initially developed as part of NASA's Small High-Altitude Science Aircraft (SHASA) program, which later evolved into the ERAST

Differences in Characteristics of Aviation Accidents During 1993-2012 Based on Aircraft Type

Science.gov (United States)

Evans, Joni K.

2015-01-01

Civilian aircraft are available in a variety of sizes, engine types, construction materials and instrumentation complexity. For the analysis reported here, eleven aircraft categories were developed based mostly on aircraft size and engine type, and these categories were applied to twenty consecutive years of civil aviation accidents. Differences in various factors were examined among these aircraft types, including accident severity, pilot characteristics and accident occurrence categories. In general, regional jets and very light sport aircraft had the lowest rates of adverse outcomes (injuries, fatal accidents, aircraft destruction, major accidents), while aircraft with twin (piston) engines or with a single (piston) engine and retractable landing gear carried the highest incidence of adverse outcomes. The accident categories of abnormal runway contact, runway excursions and non-powerplant system/component failures occur frequently within all but two or three aircraft types. In contrast, ground collisions, loss of control - on ground/water and powerplant system/component failure occur frequently within only one or two aircraft types. Although accidents in larger aircraft tend to have less severe outcomes, adverse outcome rates also differ among accident categories. It may be that the type of accident has as much or more influence on the outcome as the type of aircraft.

Adaptive and Online Health Monitoring System for Autonomous Aircraft

OpenAIRE

Mokhtar, Maizura; Zapatel-Bayo, Sergio Z.; Hussein, Saed; Howe, Joe M.

2012-01-01

Good situation awareness is one of the key attributes required to maintain safe flight, especially for an Unmanned Aerial System (UAS). Good situation awareness can be achieved by incorporating an Adaptive Health Monitoring System (AHMS) to the aircraft. The AHMS monitors the flight outcome or flight behaviours of the aircraft based on its external environmental conditions and the behaviour of its internal systems. The AHMS does this by associating a health value to the aircraft's behaviour b...

Full-scale aircraft tire pressure tests

OpenAIRE

FABRE, C; BALAY, Jean Maurice; LERAT, P; MAZARS, A

2009-01-01

This paper describes an outdoor full-scale test planned to improve experimental and theoretical knowledge related to the effects of aircraft internal tire inflation pressure on the behavior and damage of flexible pavement. Since modern aircraft can have tire pressures greater than 15 bar, the tests will focus on pressures from 15 bar to 17.5 bar. The experimental pavement located on the Toulouse-Blagnac airport in France will include up to seven al different test sections, representative of c...

The Aircraft Industry, 2006

National Research Council Canada - National Science Library

Daniel, Keith

2006-01-01

.... and global economic growth. The overall outlook for the industry is positive. Orders for commercial aircraft are up from a boom in air travel that is likely to continue well into the next decade...

Human reliability in non-destructive inspections of nuclear power plant components: modeling and analysis

Energy Technology Data Exchange (ETDEWEB)

Vasconcelos, Vanderley de; Soares, Wellington Antonio; Marques, Raíssa Oliveira; Silva Júnior, Silvério Ferreira da; Raso, Amanda Laureano, E-mail: vasconv@cdtn.br, E-mail: soaresw@cdtn.br, E-mail: raissaomarques@gmail.com, E-mail: silvasf@cdtn.br, E-mail: amandaraso@hotmail.com [Centro de Desenvolvimento da Tecnologia Nuclear (CDTN/CNEN-MG), Belo Horizonte, MG (Brazil)

2017-07-01

Non-destructive inspection (NDI) is one of the key elements in ensuring quality of engineering systems and their safe use. NDI is a very complex task, during which the inspectors have to rely on their sensory, perceptual, cognitive, and motor skills. It requires high vigilance once it is often carried out on large components, over a long period of time, and in hostile environments and restriction of workplace. A successful NDI requires careful planning, choice of appropriate NDI methods and inspection procedures, as well as qualified and trained inspection personnel. A failure of NDI to detect critical defects in safety-related components of nuclear power plants, for instance, may lead to catastrophic consequences for workers, public and environment. Therefore, ensuring that NDI methods are reliable and capable of detecting all critical defects is of utmost importance. Despite increased use of automation in NDI, human inspectors, and thus human factors, still play an important role in NDI reliability. Human reliability is the probability of humans conducting specific tasks with satisfactory performance. Many techniques are suitable for modeling and analyzing human reliability in NDI of nuclear power plant components. Among these can be highlighted Failure Modes and Effects Analysis (FMEA) and THERP (Technique for Human Error Rate Prediction). The application of these techniques is illustrated in an example of qualitative and quantitative studies to improve typical NDI of pipe segments of a core cooling system of a nuclear power plant, through acting on human factors issues. (author)

Human reliability in non-destructive inspections of nuclear power plant components: modeling and analysis

International Nuclear Information System (INIS)

Vasconcelos, Vanderley de; Soares, Wellington Antonio; Marques, Raíssa Oliveira; Silva Júnior, Silvério Ferreira da; Raso, Amanda Laureano

2017-01-01

Non-destructive inspection (NDI) is one of the key elements in ensuring quality of engineering systems and their safe use. NDI is a very complex task, during which the inspectors have to rely on their sensory, perceptual, cognitive, and motor skills. It requires high vigilance once it is often carried out on large components, over a long period of time, and in hostile environments and restriction of workplace. A successful NDI requires careful planning, choice of appropriate NDI methods and inspection procedures, as well as qualified and trained inspection personnel. A failure of NDI to detect critical defects in safety-related components of nuclear power plants, for instance, may lead to catastrophic consequences for workers, public and environment. Therefore, ensuring that NDI methods are reliable and capable of detecting all critical defects is of utmost importance. Despite increased use of automation in NDI, human inspectors, and thus human factors, still play an important role in NDI reliability. Human reliability is the probability of humans conducting specific tasks with satisfactory performance. Many techniques are suitable for modeling and analyzing human reliability in NDI of nuclear power plant components. Among these can be highlighted Failure Modes and Effects Analysis (FMEA) and THERP (Technique for Human Error Rate Prediction). The application of these techniques is illustrated in an example of qualitative and quantitative studies to improve typical NDI of pipe segments of a core cooling system of a nuclear power plant, through acting on human factors issues. (author)

Study of quiet turbofan STOL aircraft for short haul transportation

Science.gov (United States)

Higgins, T. P.; Stout, E. G.; Sweet, H. S.

1973-01-01

Conceptual designs of Quiet Turbofan STOL Short-Haul Transport Aircraft for the mid-1980 time period are developed and analyzed to determine their technical, operational, and economic feasibility. A matrix of aircraft using various high-lift systems and design parameters are considered. Variations in aircraft characteristics, airport geometry and location, and operational techniques are analyzed systematically to determine their effects on the market, operating economics, and community acceptance. In these studies, the total systems approach is considered to be critically important in analyzing the potential of STOL aircraft to reduce noise pollution and alleviate the increasing air corridor and airport congestion.

Passengers' perception of the safety demonstration on board an aircraft

Science.gov (United States)

Ruenruoy, Ratchada

The cabin safety demonstration on board an aircraft is one of the methods to provide safety information for passengers before aircraft takeoff. However, passengers' enthusiasm toward safety demonstrations is normally low. Therefore, the study of passengers' perception toward safety briefings on board an aircraft is important in increasing the safety awareness for the travelling public on commercial aircraft. A survey was distributed to measure the perceptions of Middle Tennessee State University (MTSU) faculty and staff, Aerospace students, and international students who have traveled in the last year. It was generally found that watching the cabin safety demonstration before aircraft takeoff was believed to be important for passengers. However, the attention to the safety demonstration remained low because the safety briefings were not good enough in terms of clear communication, particularly in the recorded audio demonstration and the live safety demonstration methods of briefing.

Aircraft engine pollution reduction.

Science.gov (United States)

Rudey, R. A.

1972-01-01

The effect of engine operation on the types and levels of the major aircraft engine pollutants is described and the major factors governing the formation of these pollutants during the burning of hydrocarbon fuel are discussed. Methods which are being explored to reduce these pollutants are discussed and their application to several experimental research programs are pointed out. Results showing significant reductions in the levels of carbon monoxide, unburned hydrocarbons, and oxides of nitrogen obtained from experimental combustion research programs are presented and discussed to point out potential application to aircraft engines. An experimental program designed to develop and demonstrate these and other advanced, low pollution combustor design methods is described. Results that have been obtained to date indicate considerable promise for reducing advanced engine exhaust pollutants to levels significantly below current engines.

MD-11 PCA - Closeup view of aircraft on ramp

Science.gov (United States)

1995-01-01

This McDonnell Douglas MD-11 has taxied to a position on the flightline at NASA's Dryden Flight Research Center, Edwards, California, following its completion of the first and second landings ever performed by a transport aircraft under engine power only (on Aug. 29, 1995). The milestone flight, with NASA research pilot and former astronaut Gordon Fullerton at the controls, was part of a NASA project to develop a computer-assisted engine control system that enables a pilot to land a plane safely when its normal control surfaces are disabled. The Propulsion-Controlled Aircraft (PCA) system uses standard autopilot controls already present in the cockpit, together with the new programming in the aircraft's flight control computers. The PCA concept is simple. For pitch control, the program increases thrust to climb and reduces thrust to descend. To turn right, the autopilot increases the left engine thrust while decreasing the right engine thrust. The initial Propulsion-Controlled Aircraft studies by NASA were carried out at Dryden with a modified twin-engine F-15 research aircraft.

78 FR 51121 - Airworthiness Directives; Piper Aircraft, Inc.

Science.gov (United States)

2013-08-20

...-0742; Directorate Identifier 2013-CE-012-AD] RIN 2120-AA64 Airworthiness Directives; Piper Aircraft...). SUMMARY: We propose to supersede an existing airworthiness directive (AD) that applies to certain Piper... identified in this AD, contact Piper Aircraft, Inc., 2926 Piper Drive, Vero Beach, Florida 32960; telephone...

NASA's Zero-g aircraft operations

Science.gov (United States)

Williams, R. K.

1988-01-01

NASA's Zero-g aircraft, operated by the Johnson Space Center, provides the unique weightless or zero-g environment of space flight for hardware development and test and astronaut training purposes. The program, which began in 1959, uses a slightly modified Boeing KC-135A aircraft, flying a parabolic trajectory, to produce weightless periods of 20 to 25 seconds. The program has supported the Mercury, Gemini, Apollo, Skylab, Apollo-Soyuz and Shuttle programs as well as a number of unmanned space operations. Typical experiments for flight in the aircraft have included materials processing experiments, welding, fluid manipulation, cryogenics, propellant tankage, satellite deployment dynamics, planetary sciences research, crew training with weightless indoctrination, space suits, tethers, etc., and medical studies including vestibular research. The facility is available to microgravity research organizations on a cost-reimbursable basis, providing a large, hands-on test area for diagnostic and support equipment for the Principal Investigators and providing an iterative-type design approach to microgravity experiment development. The facility allows concepts to be proven and baseline experimentation to be accomplished relatively inexpensively prior to committing to the large expense of a space flight.

40 CFR 141.804 - Aircraft water system operations and maintenance plan.

Science.gov (United States)

2010-07-01

...) WATER PROGRAMS (CONTINUED) NATIONAL PRIMARY DRINKING WATER REGULATIONS Aircraft Drinking Water Rule... must include the following requirements for procedures for disinfection and flushing of aircraft water system. (i) The air carrier must conduct disinfection and flushing of the aircraft water system in...

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

International Nuclear Information System (INIS)

Gao, Xian-Zhong; Hou, Zhong-Xi; Guo, Zheng; Liu, Jian-Xia; Chen, Xiao-Qian

2013-01-01

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

48 CFR 1252.228-70 - Loss of or damage to leased aircraft.

Science.gov (United States)

2010-10-01

... market value of the aircraft at the time of such loss or damage, which value may be specifically agreed to in clause 1252.228-71, “Fair Market Value of Aircraft,” less the salvage value of the aircraft... Contractor will be paid the fair market value of the aircraft as stated in the clause. (d) The Contractor...

Parallel Aircraft Trajectory Optimization with Analytic Derivatives

Science.gov (United States)

Falck, Robert D.; Gray, Justin S.; Naylor, Bret

2016-01-01

Trajectory optimization is an integral component for the design of aerospace vehicles, but emerging aircraft technologies have introduced new demands on trajectory analysis that current tools are not well suited to address. Designing aircraft with technologies such as hybrid electric propulsion and morphing wings requires consideration of the operational behavior as well as the physical design characteristics of the aircraft. The addition of operational variables can dramatically increase the number of design variables which motivates the use of gradient based optimization with analytic derivatives to solve the larger optimization problems. In this work we develop an aircraft trajectory analysis tool using a Legendre-Gauss-Lobatto based collocation scheme, providing analytic derivatives via the OpenMDAO multidisciplinary optimization framework. This collocation method uses an implicit time integration scheme that provides a high degree of sparsity and thus several potential options for parallelization. The performance of the new implementation was investigated via a series of single and multi-trajectory optimizations using a combination of parallel computing and constraint aggregation. The computational performance results show that in order to take full advantage of the sparsity in the problem it is vital to parallelize both the non-linear analysis evaluations and the derivative computations themselves. The constraint aggregation results showed a significant numerical challenge due to difficulty in achieving tight convergence tolerances. Overall, the results demonstrate the value of applying analytic derivatives to trajectory optimization problems and lay the foundation for future application of this collocation based method to the design of aircraft with where operational scheduling of technologies is key to achieving good performance.

Experiments Result in Safer, Spin-Resistant Aircraft

Science.gov (United States)

2014-01-01

The General Aviation Spin Program at Langley Research Center devised the first-of-their-kind guidelines for designing more spin-resistant aircraft. Thanks to NASA's contributions, the Federal Aviation Administration introduced the Part 23 spin-resistance standard in 1991. Los Angeles-based ICON Aircraft has now manufactured a new plane for consumer recreational flying that meets the complete set of criteria specified for Part 23 testing.

22 CFR 121.3 - Aircraft and related articles.

Science.gov (United States)

2010-04-01

... 22 Foreign Relations 1 2010-04-01 2010-04-01 false Aircraft and related articles. 121.3 Section 121.3 Foreign Relations DEPARTMENT OF STATE INTERNATIONAL TRAFFIC IN ARMS REGULATIONS THE UNITED STATES MUNITIONS LIST Enumeration of Articles § 121.3 Aircraft and related articles. In Category VIII...

Overview of NASA Electrified Aircraft Propulsion Research for Large Subsonic Transports

Science.gov (United States)

Jansen, Ralph H.; Bowman, Cheryl; Jankovsky, Amy; Dyson, Rodger; Felder, James L.

2017-01-01

NASA is investing in Electrified Aircraft Propulsion (EAP) research as part of the portfolio to improve the fuel efficiency, emissions, and noise levels in commercial transport aircraft. Turboelectric, partially turboelectric, and hybrid electric propulsion systems are the primary EAP configurations being evaluated for regional jet and larger aircraft. The goal is to show that one or more viable EAP concepts exist for narrow body aircraft and mature tall-pole technologies related to those concepts. A summary of the aircraft system studies, technology development, and facility development is provided. The leading concept for mid-term (2035) introduction of EAP for a single aisle aircraft is a tube and wing, partially turbo electric configuration (STARC-ABL), however other viable configurations exist. Investments are being made to raise the TRL level of light weight, high efficiency motors, generators, and electrical power distribution systems as well as to define the optimal turbine and boundary layer ingestion systems for a mid-term tube and wing configuration. An electric aircraft power system test facility (NEAT) is under construction at NASA Glenn and an electric aircraft control system test facility (HEIST) is under construction at NASA Armstrong. The correct building blocks are in place to have a viable, large plane EAP configuration tested by 2025 leading to entry into service in 2035 if the community chooses to pursue that goal.

Aircraft Engine Sensor/Actuator/Component Fault Diagnosis Using a Bank of Kalman Filters

Science.gov (United States)

Kobayashi, Takahisa; Simon, Donald L. (Technical Monitor)

2003-01-01

In this report, a fault detection and isolation (FDI) system which utilizes a bank of Kalman filters is developed for aircraft engine sensor and actuator FDI in conjunction with the detection of component faults. This FDI approach uses multiple Kalman filters, each of which is designed based on a specific hypothesis for detecting a specific sensor or actuator fault. In the event that a fault does occur, all filters except the one using the correct hypothesis will produce large estimation errors, from which a specific fault is isolated. In the meantime, a set of parameters that indicate engine component performance is estimated for the detection of abrupt degradation. The performance of the FDI system is evaluated against a nonlinear engine simulation for various engine faults at cruise operating conditions. In order to mimic the real engine environment, the nonlinear simulation is executed not only at the nominal, or healthy, condition but also at aged conditions. When the FDI system designed at the healthy condition is applied to an aged engine, the effectiveness of the FDI system is impacted by the mismatch in the engine health condition. Depending on its severity, this mismatch can cause the FDI system to generate incorrect diagnostic results, such as false alarms and missed detections. To partially recover the nominal performance, two approaches, which incorporate information regarding the engine s aging condition in the FDI system, will be discussed and evaluated. The results indicate that the proposed FDI system is promising for reliable diagnostics of aircraft engines.

Social-Ecological Soundscapes: Examining Aircraft-Harvester-Caribou Conflict in Arctic Alaska

Science.gov (United States)

Stinchcomb, Taylor R.

As human development expands across the Arctic, it is crucial to carefully assess the impacts to remote natural ecosystems and to indigenous communities that rely on wild resources for nutritional and cultural wellbeing. Because indigenous communities and wildlife populations are interdependent, assessing how human activities impact traditional harvest practices can advance our understanding of the human dimensions of wildlife management. Indigenous communities across Arctic Alaska have expressed concern over the last four decades that low-flying aircraft interfere with their traditional harvest practices. For example, communities often have testified that aircraft disturb caribou (Rangifer tarandus) and thereby reduce harvest opportunities. Despite this longstanding concern, little research exists on the extent of aircraft activity in Arctic Alaska and on how aircraft affect the behavior and perceptions of harvesters. Therefore, the overarching goal of my research was to highlight the importance of aircraft-harvester conflict in Arctic Alaska and begin to address the issue using a scientific and community-driven approach. In Chapter 1, I demonstrated that conflict between aircraft and indigenous harvesters in Arctic Alaska is a widespread, understudied, and complex issue. By conducting a meta-analysis of the available literature, I quantified the deficiency of scientific knowledge about the impacts of aircraft on rural communities and traditional harvest practices in the Arctic. My results indicated that no peer-reviewed literature has addressed the conflict between low-flying aircraft and traditional harvesters in Arctic Alaska. I speculated that the scale over which aircraft, rural communities, and wildlife interact limits scientists' ability to determine causal relationships and therefore detracts from their interest in researching the human dimension of this social-ecological system. Innovative research approaches like soundscape ecology could begin to

On the unification of aircraft ultrafine particle emission data

Energy Technology Data Exchange (ETDEWEB)

Kaercher, B.; Busen, R. [DLR Deutsches Zentrum fuer Luft- und Raumfahrt e.V., Wessling (Germany). Inst. fuer Physik der Atmosphaere; Turco, R.P.; Yu Fangqun [California Univ., Los Angeles, CA (United States). Dept. of Atmospheric Sciences; Danilin, M.Y.; Weisenstein, D.K. [Atmospheric and Environmental Research, Inc., Cambridge, MA (United States); Miake-Lye, R.C. [Aerodyne Research, Inc., Billerica, MA (United States)

2000-03-01

To predict the environmental impacts of future commercial aviation, intensive studies have been launched to measure the properties and effects of aircraft emissions. These observations have revealed an extremely wide variance with respect to the number and sizes of the particles produced in the exhaust plumes. Aircraft aerosol ultimately contributes to the population of cloud-forming nuclei, and may lead to significant global radiative and chemical perturbations. In this paper, recent discoveries are coordinated and unified in the form of a physically consistent plume aerosol model that explains most of the observational variance. Using this new approach, it is now practical to carry out reliable global atmospheric simulations of aircraft effects, as demonstrated by a novel assessment of the perturbation of the stratospheric aerosol layer by a supersonic aircraft fleet. (orig.)

Satellite images to aircraft in flight. [GEOS image transmission feasibility analysis

Science.gov (United States)

Camp, D.; Luers, J. K.; Kadlec, P. W.

1977-01-01

A study has been initiated to evaluate the feasibility of transmitting selected GOES images to aircraft in flight. Pertinent observations that could be made from satellite images on board aircraft include jet stream activity, cloud/wind motion, cloud temperatures, tropical storm activity, and location of severe weather. The basic features of the Satellite Aircraft Flight Environment System (SAFES) are described. This system uses East GOES and West GOES satellite images, which are interpreted, enhanced, and then retransmitted to designated aircraft.

Riveted Lap Joints in Aircraft Fuselage Design, Analysis and Properties

CERN Document Server

Skorupa, Andrzej

2012-01-01

Fatigue of the pressurized fuselages of transport aircraft is a significant problem all builders and users of aircraft have to cope with for reasons associated with assuring a sufficient lifetime and safety, and formulating adequate inspection procedures. These aspects are all addressed in various formal protocols for creating and maintaining airworthiness, including damage tolerance considerations. In most transport aircraft, fatigue occurs in lap joints, sometimes leading to circumstances that threaten safety in critical ways. The problem of fatigue of lap joints has been considerably enlarged by the goal of extending aircraft lifetimes. Fatigue of riveted lap joints between aluminium alloy sheets, typical of the pressurized aircraft fuselage, is the major topic of the present book. The richly illustrated and well-structured chapters treat subjects such as: structural design solutions and loading conditions for fuselage skin joints; relevance of laboratory test results for simple lap joint specimens to rive...

Cost Valuation: A Model for Comparing Dissimilar Aircraft Platforms

National Research Council Canada - National Science Library

Long, Eric J

2006-01-01

.... A demonstration of the model's validity using aircraft and cost data from the Predator UAV and the F-16 was then performed to illustrate how it can be used to aid comparisons of dissimilar aircraft...

Fuel-conservative guidance system for powered-lift aircraft

Science.gov (United States)

Erzberger, H.; Mclean, J. D.

1979-01-01

A concept for automatic terminal area guidance, comprising two modes of operation, was developed and evaluated in flight tests. In the predictive mode, fuel efficient approach trajectories are synthesized in fast time. In the tracking mode, the synthesized trajectories are reconstructed and tracked automatically. An energy rate performance model derived from the lift, drag, and propulsion system characteristics of the aircraft is used in the synthesis algorithm. The method optimizes the trajectory for the initial aircraft position and wind and temperature profiles encountered during each landing approach. The design theory and the results of simulations and flight tests using the Augmentor Wing Jet STOL Research Aircraft are described.

Environmental compatibility of CRYOPLANE the cryogenic-fuel aircraft

Energy Technology Data Exchange (ETDEWEB)

Klug, H.G. [Daimler Benz Aerospace Airbus, Hamburg (Germany)

1997-12-31

`CRYOPLANE` is the project name for an aircraft powered by cryogenic fuel, either liquid natural gas (LNG, mainly consisting of methane) or liquid hydrogen (LH{sub 2}). Emission of CO{sub 2}, unburnt hydrocarbons, soot and sulfur will be completely avoided by hydrogen combustion: LH{sub 2} is an extremely pure liquid. Emission of water as a primary combustion product is increased by a factor of 2.6. Exhaust gases behind hydrogen engines contain more water than behind kerosene engines, and hence can form contrails under a wider range of atmospheric conditions. Liquid hydrogen fueled aircraft promise big advantages relative to kerosene aircraft in terms of environmental compatibility. (R.P.)

Environmental compatibility of CRYOPLANE the cryogenic-fuel aircraft

Energy Technology Data Exchange (ETDEWEB)

Klug, H G [Daimler Benz Aerospace Airbus, Hamburg (Germany)

1998-12-31

`CRYOPLANE` is the project name for an aircraft powered by cryogenic fuel, either liquid natural gas (LNG, mainly consisting of methane) or liquid hydrogen (LH{sub 2}). Emission of CO{sub 2}, unburnt hydrocarbons, soot and sulfur will be completely avoided by hydrogen combustion: LH{sub 2} is an extremely pure liquid. Emission of water as a primary combustion product is increased by a factor of 2.6. Exhaust gases behind hydrogen engines contain more water than behind kerosene engines, and hence can form contrails under a wider range of atmospheric conditions. Liquid hydrogen fueled aircraft promise big advantages relative to kerosene aircraft in terms of environmental compatibility. (R.P.)

Aircraft and ground vehicle friction measurements obtained under winter runway conditions

Science.gov (United States)

Yager, Thomas J.

1989-01-01

Tests with specially instrumented NASA B-737 and B-727 aircraft together with several different ground friction measuring devices have been conducted for a variety of runway surface types and wetness conditions. This effort is part of the Joint FAA/NASA Aircraft/Ground Vehicle Runway Friction Program aimed at obtaining a better understanding of aircraft ground handling performance under adverse weather conditions, and defining relationships between aircraft and ground vehicle tire friction measurements. Aircraft braking performance on dry, wet, snow-, and ice-covered runway conditions is discussed together with ground vehicle friction data obtained under similar runway conditions. For the wet, compacted snow- and ice-covered runway conditions, the relationship between ground vehicles and aircraft friction data is identified. The influence of major test parameters on friction measurements such as speed, test tire characteristics, and surface contaminant-type are discussed. The test results indicate that use of properly maintained and calibrated ground vehicles for monitoring runway friction conditions should be encouraged particularly under adverse weather conditions.

36 CFR 1002.17 - Aircraft and air delivery.

Science.gov (United States)

2010-07-01

... 36 Parks, Forests, and Public Property 3 2010-07-01 2010-07-01 false Aircraft and air delivery. 1002.17 Section 1002.17 Parks, Forests, and Public Property PRESIDIO TRUST RESOURCE PROTECTION, PUBLIC USE AND RECREATION § 1002.17 Aircraft and air delivery. (a) Delivering or retrieving a person or...

Confirmatory Factor Analysis and Multiple Linear Regression of the Neck Disability Index: Assessment If Subscales Are Equally Relevant in Whiplash and Nonspecific Neck Pain.

Science.gov (United States)

Croft, Arthur C; Milam, Bryce; Meylor, Jade; Manning, Richard

2016-06-01

Because of previously published recommendations to modify the Neck Disability Index (NDI), we evaluated the responsiveness and dimensionality of the NDI within a population of adult whiplash-injured subjects. The purpose of the present study was to evaluate the responsiveness and dimensionality of the NDI within a population of adult whiplash-injured subjects. Subjects who had sustained whiplash injuries of grade 2 or higher completed an NDI questionnaire. There were 123 subjects (55% female, of which 36% had recovered and 64% had chronic symptoms. NDI subscales were analyzed using confirmatory factor analysis, considering only the subscales and, secondly, using sex as an 11th variable. The subscales were also tested with multiple linear regression modeling using the total score as a target variable. When considering only the 10 NDI subscales, only a single factor emerged, with an eigenvalue of 5.4, explaining 53.7% of the total variance. Strong correlation (> .55) (P factor model of the NDI is not justified based on our results, and in this population of whiplash subjects, the NDI was unidimensional, demonstrating high internal consistency and supporting the original validation study of Vernon and Mior.

47 CFR 87.47 - Application for a portable aircraft station license.

Science.gov (United States)

2010-10-01

... 47 Telecommunication 5 2010-10-01 2010-10-01 false Application for a portable aircraft station... SPECIAL RADIO SERVICES AVIATION SERVICES Applications and Licenses § 87.47 Application for a portable aircraft station license. A person may apply for a portable aircraft radio station license if the need...

Aircraft 4D trajectories planning under uncertainties

OpenAIRE

Chaimatanan , Supatcha; Delahaye , Daniel; Mongeau , Marcel

2015-01-01

International audience; To sustain the rapidly increasing air traffic demand, the future air traffic management system will rely on a concept, called Trajectory-Based Operations (TBO), that will require aircraft to follow an assigned 4D trajectory (time-constrained trajectory) with high precision. TBO involves separating aircraft via strategic (long-term) trajectory deconfliction rather than the currently-practicing tactical (short-term) conflict resolution. In this context, this paper presen...

Robust Aircraft Squadron Scheduling in the Face of Absenteeism

National Research Council Canada - National Science Library

Gokcen, Osman B

2008-01-01

Air Force fighter aircraft squadrons the world over share a unique problem. Each requires complex training schedules coupling aircraft to pilots, the duo to missions and airspaces, and then the entire combination to a feasible time slot...

Microstructure and Aging of Powder-Metallurgy Al Alloys

Science.gov (United States)

Blackburn, L. B.

1987-01-01

Report describes experimental study of thermal responses and aging behaviors of three new aluminum alloys. Alloys produced from rapidly solidified powders and contain 3.20 to 5.15 percent copper, 0.24 to 1.73 percent magnesium, 0.08 to 0.92 percent iron, and smaller amounts of manganese, nickel, titanium, silicon, and zinc. Peak hardness achieved at lower aging temperatures than with standard ingot-metallurgy alloys. Alloys of interest for automobile, aircraft, and aerospace applications.

Dynamics and control of robotic aircraft with articulated wings

Science.gov (United States)

Paranjape, Aditya Avinash

There is a considerable interest in developing robotic aircraft, inspired by birds, for a variety of missions covering reconnaissance and surveillance. Flapping wing aircraft concepts have been put forth in light of the efficiency of flapping flight at small scales. These aircraft are naturally equipped with the ability to rotate their wings about the root, a form of wing articulation. This thesis covers some problems concerning the performance, stability and control of robotic aircraft with articulated wings in gliding flight. Specifically, we are interested in aircraft without a vertical tail, which would then use wing articulation for longitudinal as well as lateral-directional control. Although the dynamics and control of articulated wing aircraft share several common features with conventional fixed wing aircraft, the presence of wing articulation presents several unique benefits as well as limitations from the perspective of performance and control. One of the objective of this thesis is to understand these features using a combination of theoretical and numerical tools. The aircraft concept envisioned in this thesis uses the wing dihedral angles for longitudinal and lateral-directional control. Aircraft with flexible articulated wings are also investigated. We derive a complete nonlinear model of the flight dynamics incorporating dynamic CG location and the changing moment of inertia. We show that symmetric dihedral configuration, along with a conventional horizontal tail, can be used to control flight speed and flight path angle independently of each other. This characteristic is very useful for initiating an efficient perching maneuver. It is shown that wing dihedral angles alone can effectively regulate sideslip during rapid turns and generate a wide range of equilibrium turn rates while maintaining a constant flight speed and regulating sideslip. We compute the turning performance limitations that arise due to the use of wing dihedral for yaw control

36 CFR 2.17 - Aircraft and air delivery.

Science.gov (United States)

2010-07-01

... 36 Parks, Forests, and Public Property 1 2010-07-01 2010-07-01 false Aircraft and air delivery. 2.17 Section 2.17 Parks, Forests, and Public Property NATIONAL PARK SERVICE, DEPARTMENT OF THE INTERIOR RESOURCE PROTECTION, PUBLIC USE AND RECREATION § 2.17 Aircraft and air delivery. (a) The following are...

THE FUTURE OF PASSENGER AIR TRANSPORT – VERY LARGE AIRCRAFT AND OUT KEY HUMAN FACTORS AFFECTING THE OPERATION AND SAFETY OF PASSENGER AIR TRANSPORT

Directory of Open Access Journals (Sweden)

Petra Skolilova

2017-12-01

Full Text Available The article outlines some human factors affecting the operation and safety of passenger air transport given the massive increase in the use of the VLA. Decrease of the impact of the CO2 world emissions is one of the key goals for the new aircraft design. The main wave is going to reduce the burned fuel. Therefore, the eco-efficiency engines combined with reasonable economic operation of the aircraft are very important from an aviation perspective. The prediction for the year 2030 says that about 90% of people, which will use long-haul flights to fly between big cities. So, the A380 was designed exactly for this time period, with a focus on the right capacity, right operating cost and right fuel burn per seat. There is no aircraft today with better fuel burn combined with eco-efficiency per seat, than the A380. The very large aircrafts (VLAs are the future of the commercial passenger aviation. Operating cost versus safety or CO2 emissions versus increasing automation inside the new generation aircraft. Almost 80% of the world aircraft accidents are caused by human error based on wrong action, reaction or final decision of pilots, the catastrophic failures of aircraft systems, or air traffic control errors are not so frequent. So, we are at the beginning of a new age in passenger aviation and the role of the human factor is more important than ever.

Preliminary study of impact fragility to RC wall subjected to aircraft impact

International Nuclear Information System (INIS)

Shin, Sang Shup; Hahm, Dae Gi; Choi, In Kil

2012-01-01

International experience has shown that internal and external hazards such as fires, earthquakes, and aircraft impacts can be significant safety contributors to the risk to infrastructures such as nuclear power plants. Since the aircraft accident at the World Trade Center (WTC) on September 11, 2001, an aircraft impact problem has been increasingly of the interest and is one of important categories of an unexpected external hazard field. To date, aircraft impact analyses has most focused on the response analysis to the target structures. However, this preliminary study carried out an impact fragility analysis to reinforced concrete (RC) wall subjected to an aircraft impact. The aircraft velocity is used as the important variable of this study. The impact analysis of the applied Ri era's forcing function is used by Abaqus/Explicit

Neurodevelopmental Outcomes of Infants Born at <29 Weeks of Gestation Admitted to Canadian Neonatal Intensive Care Units Based on Location of Birth.

Science.gov (United States)

Amer, Reem; Moddemann, Diane; Seshia, Mary; Alvaro, Ruben; Synnes, Anne; Lee, Kyong-Soon; Lee, Shoo K; Shah, Prakesh S

2018-05-01

To compare mortality and neurodevelopmental outcomes of outborn and inborn preterm infants born at neurodevelopmental impairment (NDI), and overall NDI were compared between outborn and inborn infants at 18-21 months of age, corrected for prematurity. Of 2951 eligible infants, 473 (16%) were outborn. Mean birth weight (940 ± 278 g vs 897 + 237 g), rates of treatment with antenatal steroids (53.9% vs 92.9%), birth weight small for gestational age (5.3% vs 9.4%), and maternal college education (43.7% vs 53.9%) differed between outborn and inborn infants, respectively (all P values neurodevelopmental impairment were significantly higher in outborn compared with inborn infants admitted to Canadian NICUs. Adverse outcomes were mainly attributed to increased mortality and cerebral palsy in outborn neonates. Copyright © 2017 Elsevier Inc. All rights reserved.

Low-Cost Composite Materials and Structures for Aircraft Applications

Science.gov (United States)

Deo, Ravi B.; Starnes, James H., Jr.; Holzwarth, Richard C.

2003-01-01

A survey of current applications of composite materials and structures in military, transport and General Aviation aircraft is presented to assess the maturity of composites technology, and the payoffs realized. The results of the survey show that performance requirements and the potential to reduce life cycle costs for military aircraft and direct operating costs for transport aircraft are the main reasons for the selection of composite materials for current aircraft applications. Initial acquisition costs of composite airframe components are affected by high material costs and complex certification tests which appear to discourage the widespread use of composite materials for aircraft applications. Material suppliers have performed very well to date in developing resin matrix and fiber systems for improved mechanical, durability and damage tolerance performance. The next challenge for material suppliers is to reduce material costs and to develop materials that are suitable for simplified and inexpensive manufacturing processes. The focus of airframe manufacturers should be on the development of structural designs that reduce assembly costs by the use of large-scale integration of airframe components with unitized structures and manufacturing processes that minimize excessive manual labor.

Risk assessment of aircraft accidents anywhere near an airport

International Nuclear Information System (INIS)

Barbaran, Gustavo; Jensen Mariani Santiago Nicolas

2011-01-01

This work analyzes the more suitable areas to build new facilities, taking into account the conditions imposed by an airport located nearby. Initially, it describes the major characteristics of the airport. Then, the restrictions imposed to ensure the normal operation of the aircraft are analyzed. Following, there is a summary of the evolution of studies of aircraft accidents at nuclear facilities. In the second part, three models of aircraft crash probabilities are presented, all of them developed in the U.S.A, each with an increasing level of complexity in modeling the likelihood of accidents. The first model is the 'STD-3014' Department of Energy (DOE), the second is the 'ACRAM'(Aircraft Crash Risk Assessment Methodology) prepared by the 'Lawrence Livermore National Laboratory'(LLNL) and finally the more advanced 'ACRP-3', produced by the 'Transportation Research Board'. The results obtained with the three models establish that the risks imposed on the airport vicinity, remain low due to the improvement and innovation in the aircraft's safety, reducing the risk margin for the location of new nuclear facilities near an airport. (author) [es

Structural analysis of aircraft impact on a nuclear powered ship

International Nuclear Information System (INIS)

Dietrich, R.

1976-01-01

As part of a general safety analysis, the reliability against structural damage due to an aircraft crash on a nuclear powered ship is evaluated. This structural analysis is an aid in safety design. It is assumed that a Phantom military jet-fighter hits a nuclear powered ship. The total reaction force due to such an aircraft impact on a rigid barrier is specified in the guidelines of the Reaktor-Sicherheitskommission (German Safety Advisory Committee) for pressurized water reactors. This paper investigates the aircraft impact on the collision barrier at the side of the ship. The aircraft impact on top of the reactor hatchway is investigated by another analysis. It appears that the most unfavorable angle of impact is always normal to the surface of the collision barrier. Consequently, only normal impact will be considered here. For the specific case of an aircraft striking a nuclear powered ship, the following two effects are considered: Local penetration and dynamic response of the structure. (Auth.)

An Overview of Virtual Acoustic Simulation of Aircraft Flyover Noise

Science.gov (United States)

Rizzi, Stephen A.

2013-01-01

Methods for testing human subject response to aircraft flyover noise have greatly advanced in recent years as a result of advances in simulation technology. Capabilities have been developed which now allow subjects to be immersed both visually and aurally in a three-dimensional, virtual environment. While suitable for displaying recorded aircraft noise, the true potential is found when synthesizing aircraft flyover noise because it allows the flexibility and freedom to study sounds from aircraft not yet flown. A virtual acoustic simulation method is described which is built upon prediction-based source noise synthesis, engineering-based propagation modeling, and empirically-based receiver modeling. This source-path-receiver paradigm allows complete control over all aspects of flyover auralization. With this capability, it is now possible to assess human response to flyover noise by systematically evaluating source noise reductions within the context of a system level simulation. Examples of auralized flyover noise and movie clips representative of an immersive aircraft flyover environment are made in the presentation.

Portable Wireless Device Threat Assessment for Aircraft Navigation Radios

Science.gov (United States)

Nguyen, Truong X.; Koppen, Sandra V.; Ely, Jay J.; Williams, Reuben A.; Smith, Laura J.; Salud, Maria Theresa P.

2004-01-01

This paper addresses the concern for Wireless Local Area Network devices and two-way radios to cause electromagnetic interference to aircraft navigation radio systems. Spurious radiated emissions from various IEEE 802.11a, 802.11b, and Bluetooth devices are characterized using reverberation chambers. The results are compared with baseline emissions from standard laptop computer and personal digital assistants (PDAs) that are currently allowed for use on aircraft. The results indicate that the WLAN devices tested are not more of a threat to aircraft navigation radios than standard laptop computers and PDAs in most aircraft bands. In addition, spurious radiated emission data from seven pairs of two-way radios are provided. These two-way radios emit at much higher levels in the bands considered. A description of the measurement process, device modes of operation and the measurement results are reported.

Nuclear containment structure subjected to commercial and fighter aircraft crash

International Nuclear Information System (INIS)

Sadique, M.R.; Iqbal, M.A.; Bhargava, P.

2013-01-01

Highlights: • Nuclear containment response has been studied against aircraft crash. • Concrete damaged plasticity and Johnson–Cook elasto-viscoplastic models were employed. • Boeing 747-400 and Boeing 767-400 aircrafts caused global failure of containment. • Airbus A320 and Boeing 707-320 aircrafts caused local damage. • Tension damage of concrete was found more prominent compared to compression damage. -- Abstract: The response of a boiling water reactor (BWR) nuclear containment vessel has been studied against commercial and fighter aircraft crash using a nonlinear finite element code ABAQUS. The aircrafts employed were Boeing 747-400, Boeing 767-400, Airbus A-320, Boeing 707-320 and Phantom F4. The containment was modeled as a three-dimensional deformable reinforced concrete structure while the loading of aircraft was assigned using the respective reaction–time curve. The location of strike was considered near the junction of dome and cylinder, and the angle of incidence, normal to the containment surface. The material behavior of the concrete was incorporated using the damaged plasticity model while that of the reinforcement, the Johnson–Cook elasto-viscoplastic model. The containment could not sustain the impact of Boeing 747-400 and Boeing 767-400 aircrafts and suffered rupture of concrete around the impact region leading to global failure. On the other hand, the maximum local deformation at the point of impact was found to be 0.998 m, 0.099 m, 0.092 m, 0.089 m, and 0.074 m against Boeing 747-400, Phantom F4, Boeing 767, Boeing 707-320 and Airbus A-320 aircrafts respectively. The results of the present study were compared with those of the previous analytical and numerical investigations with respect to the maximum deformation and overall behavior of the containment

Nuclear containment structure subjected to commercial and fighter aircraft crash

Energy Technology Data Exchange (ETDEWEB)

Sadique, M.R., E-mail: rehan.sadique@gmail.com; Iqbal, M.A., E-mail: iqbalfce@iitr.ernet.in; Bhargava, P., E-mail: bhpdpfce@iitr.ernet.in

2013-07-15

Highlights: • Nuclear containment response has been studied against aircraft crash. • Concrete damaged plasticity and Johnson–Cook elasto-viscoplastic models were employed. • Boeing 747-400 and Boeing 767-400 aircrafts caused global failure of containment. • Airbus A320 and Boeing 707-320 aircrafts caused local damage. • Tension damage of concrete was found more prominent compared to compression damage. -- Abstract: The response of a boiling water reactor (BWR) nuclear containment vessel has been studied against commercial and fighter aircraft crash using a nonlinear finite element code ABAQUS. The aircrafts employed were Boeing 747-400, Boeing 767-400, Airbus A-320, Boeing 707-320 and Phantom F4. The containment was modeled as a three-dimensional deformable reinforced concrete structure while the loading of aircraft was assigned using the respective reaction–time curve. The location of strike was considered near the junction of dome and cylinder, and the angle of incidence, normal to the containment surface. The material behavior of the concrete was incorporated using the damaged plasticity model while that of the reinforcement, the Johnson–Cook elasto-viscoplastic model. The containment could not sustain the impact of Boeing 747-400 and Boeing 767-400 aircrafts and suffered rupture of concrete around the impact region leading to global failure. On the other hand, the maximum local deformation at the point of impact was found to be 0.998 m, 0.099 m, 0.092 m, 0.089 m, and 0.074 m against Boeing 747-400, Phantom F4, Boeing 767, Boeing 707-320 and Airbus A-320 aircrafts respectively. The results of the present study were compared with those of the previous analytical and numerical investigations with respect to the maximum deformation and overall behavior of the containment.

Calculation of odour emissions from aircraft engines at Copenhagen Airport

Energy Technology Data Exchange (ETDEWEB)

Winther, Morten; Kousgaard, Uffe [National Environmental Research Institute, Frederiksborgvej 399, 4000 Roskilde (Denmark); Oxboel, Arne [FORCE Technology, Park Alle 345, 2605 Broendby (Denmark)

2006-07-31

In a new approach the odour emissions from aircraft engines at Copenhagen Airport are calculated using actual fuel flow and emission measurements (one main engine and one APU: Auxiliary Power Unit), odour panel results, engine specific data and aircraft operational data for seven busy days. The calculation principle assumes a linear relation between odour and HC emissions. Using a digitalisation of the aircraft movements in the airport area, the results are depicted on grid maps, clearly reflecting aircraft operational statistics as single flights or total activity during a whole day. The results clearly reflect the short-term temporal fluctuations of the emissions of odour (and exhaust gases). Aircraft operating at low engine thrust (taxiing, queuing and landing) have a total odour emission share of almost 98%, whereas the shares for the take off/climb out phases (2%) and APU usage (0.5%) are only marginal. In most hours of the day, the largest odour emissions occur, when the total amount of fuel burned during idle is high. However, significantly higher HC emissions for one specific engine cause considerable amounts of odour emissions during limited time periods. The experimentally derived odour emission factor of 57 OU/mg HC is within the range of 23 and 110 OU/mg HC used in other airport odour studies. The distribution of odour emission results between aircraft operational phases also correspond very well with the results for these other studies. The present study uses measurement data for a representative engine. However, the uncertainties become large when the experimental data is used to estimate the odour emissions for all aircraft engines. More experimental data is needed to increase inventory accuracy, and in terms of completeness it is recommended to make odour emission estimates also for engine start and the fuelling of aircraft at Copenhagen Airport in the future. (author)

Calculation of odour emissions from aircraft engines at Copenhagen Airport.

Science.gov (United States)

Winther, Morten; Kousgaard, Uffe; Oxbøl, Arne

2006-07-31

In a new approach the odour emissions from aircraft engines at Copenhagen Airport are calculated using actual fuel flow and emission measurements (one main engine and one APU: Auxiliary Power Unit), odour panel results, engine specific data and aircraft operational data for seven busy days. The calculation principle assumes a linear relation between odour and HC emissions. Using a digitalisation of the aircraft movements in the airport area, the results are depicted on grid maps, clearly reflecting aircraft operational statistics as single flights or total activity during a whole day. The results clearly reflect the short-term temporal fluctuations of the emissions of odour (and exhaust gases). Aircraft operating at low engine thrust (taxiing, queuing and landing) have a total odour emission share of almost 98%, whereas the shares for the take off/climb out phases (2%) and APU usage (0.5%) are only marginal. In most hours of the day, the largest odour emissions occur, when the total amount of fuel burned during idle is high. However, significantly higher HC emissions for one specific engine cause considerable amounts of odour emissions during limited time periods. The experimentally derived odour emission factor of 57 OU/mg HC is within the range of 23 and 110 OU/mg HC used in other airport odour studies. The distribution of odour emission results between aircraft operational phases also correspond very well with the results for these other studies. The present study uses measurement data for a representative engine. However, the uncertainties become large when the experimental data is used to estimate the odour emissions for all aircraft engines. More experimental data is needed to increase inventory accuracy, and in terms of completeness it is recommended to make odour emission estimates also for engine start and the fuelling of aircraft at Copenhagen Airport in the future.

Assessment of sensors and aircraft for oil spill remote sensing

International Nuclear Information System (INIS)

Fingas, M.F.; Fruhwirth, M.

1993-01-01

Environment Canada has assessed sensors and aircraft suitable for remote sensing, particularly the capability of sensors to detect oil and to discriminate oil from background targets. The assessment was based on past experience and technical considerations. The first sensor recommended for use is an infrared camera or an IR/UV system. This recommendation is based on the system's ability to detect oil and discriminate this from the background, and the low cost of these sensors. The laser fluorosensor is recommended as the second device, as it is the only unit capable of positively discriminating oil on water, among weeds, and in sediment or beach material. Cameras operating in the visible region of the spectrum are recommended for two functions: documentation and providing background or location imagery for other sensors. Imaging radars, be they SAR or SLAR, are recommended for long-range searches or for oil spill work at night or when fog is present. Radars are expensive and require dedicated aircraft. Passive microwave devices are currently being developed but have not been proven as an alternative to radar or for measuring slick thickness. A laser based thickness sensor is under development. Satellite systems were also assessed. Satellite sensors operating in the visible spectrum have only limited application to major oil spills. New radar sensors show limited potential. The major limitation of any satellite system is the limited coverage time that is a function of its orbit. A study of aircraft and aircraft modifications was carried out to catalog aircraft modifications necessary to operate oil spill remote sensors. A potential user could select modifications that are already approved and thus save the high costs of aircraft modification design. The modifications already approved in Canada and the US for a given aircraft provide criteria for the selection of an aircraft

Environmental Aspects of Aircraft and Airfield Deicing - An Air Force Perspective

Science.gov (United States)

2010-11-01

e l l e n c e COD of Aircraft Deicers ADF Kg O2/Kg compd Ethylene glycol 1.14 T Propylene glycol 1.47 T Isopropyl alcohol 2.11 T Neopentyl glycol ...showed that commercial airports use about 25 million gallons of Aircraft Deicing Fluid (ADF) annually, of which 22.1 M (88%) is Propylene Glycol (PG...S e r v i c e - E x c e l l e n c e AF Aircraft Deicing Overview 70% (107) of bases reported using aircraft deicers Propylene Glycol (PG), AMS 1424

77 FR 56581 - Airworthiness Directives; Sikorsky Aircraft Corporation Helicopters

Science.gov (United States)

2012-09-13

... Corporation Helicopters AGENCY: Federal Aviation Administration (FAA), DOT. ACTION: Supplemental notice of... airworthiness directive (AD) for the Sikorsky Aircraft Corporation (Sikorsky) Model S-92A helicopter, which... proposed AD, contact Sikorsky Aircraft Corporation, Attn: Manager, Commercial Technical Support, mailstop...

Development of an Unmanned Aircraft Systems Program: ACUASI

Science.gov (United States)

Webley, P. W.; Cahill, C. F.; Rogers, M.; Hatfield, M. C.

2017-12-01

The Alaska Center for Unmanned Aircraft Systems Integration (ACUASI) has developed a comprehensive program that incorporates pilots, flight/mission planners, geoscientists, university undergraduate and graduate students, and engineers together as one. We lead and support unmanned aircraft system (UAS) missions for geoscience research, emergency response, humanitarian needs, engineering design, and policy development. We are the University of Alaska's UAS research program, lead the Federal Aviation Administration (FAA) Pan-Pacific UAS Test Range Complex (PPUTRC) with Hawaii, Oregon, and Mississippi and in 2015 became a core member of the FAA Center of Excellence for UAS Research, managed by Mississippi State University. ACUASI's suite of aircraft include small hand-launched/vertical take-off and landing assets for short-term rapid deployment to large fixed-wing gas powered systems that provide multiple hours of flight time. We have extensive experience in Arctic and sub-Arctic environments and will present on how we have used our aircraft and payloads in numerous missions that include beyond visual line of sight flights, mapping the river ice-hazard in Alaska during spring break-up, and providing UAS-based observations for local Alaskans to navigate through the changing ice shelf of Northern Alaska. Several sensor developments of interest in the near future include building payloads for thermal infrared mapping at high spatial resolutions, combining forward and nadir looking cameras on the same UAS aircraft for topographic mapping, and using neutral density and narrow band filters to map very high temperature thermally active hazards, such as forest fires and volcanic eruptions. The ACUASI team working together provide us the experience, tools, capabilities, and personnel to build and maintain a world class research center for unmanned aircraft systems as well as support both real-time operations and geoscience research.

Integrating the Base of Aircraft Data (BADA) in CTAS Trajectory Synthesizer

Science.gov (United States)

Abramson, Michael; Ali, Kareem

2012-01-01

The Center-Terminal Radar Approach Control (TRACON) Automation System (CTAS), developed at NASA Ames Research Center for assisting controllers in the management and control of air traffic in the extended terminal area, supports the modeling of more than four hundred aircraft types. However, 90% of them are supported indirectly by mapping them to one of a relatively few aircraft types for which CTAS has detailed drag and engine thrust models. On the other hand, the Base of Aircraft Data (BADA), developed and maintained by Eurocontrol, supports more than 300 aircraft types, about one third of which are directly supported, i.e. they have validated performance data. All these data were made available for CTAS by integrating BADA version 3.8 into CTAS Trajectory Synthesizer (TS). Several validation tools were developed and used to validate the integrated code and to evaluate the accuracy of trajectory predictions generated using CTAS "native" and BADA Aircraft Performance Models (APM) comparing them with radar track data. Results of these comparisons indicate that the two models have different strengths and weaknesses. The BADA APM can improve the accuracy of CTAS predictions at least for some aircraft types, especially small aircraft, and for some flight phases, especially climb.

Analysis of Asymmetric Aircraft Aerodynamics Due to an Experimental Wing Glove

Science.gov (United States)

Hartshorn, Fletcher

2011-01-01

Aerodynamic analysis on a business jet with a wing glove attached to one wing is presented and discussed. If a wing glove is placed over a portion of one wing, there will be asymmetries in the aircraft as well as overall changes in the forces and moments acting on the aircraft. These changes, referred to as deltas, need to be determined and quantified to make sure the wing glove does not have a drastic effect on the aircraft flight characteristics. TRANAIR, a non-linear full potential solver was used to analyze a full aircraft, with and without a glove, at a variety of flight conditions and angles of attack and sideslip. Changes in the aircraft lift, drag and side force, along with roll, pitch and yawing moment are presented. Span lift and moment distributions are also presented for a more detailed look at the effects of the glove on the aircraft. Aerodynamic flow phenomena due to the addition of the glove and its fairing are discussed. Results show that the glove used here does not present a drastic change in forces and moments on the aircraft, but an added torsional moment around the quarter-chord of the wing may be a cause for some structural concerns.

Small Aircraft Data Distribution System

Science.gov (United States)

Chazanoff, Seth L.; Dinardo, Steven J.

2012-01-01

The CARVE Small Aircraft Data Distribution System acquires the aircraft location and attitude data that is required by the various programs running on a distributed network. This system distributes the data it acquires to the data acquisition programs for inclusion in their data files. It uses UDP (User Datagram Protocol) to broadcast data over a LAN (Local Area Network) to any programs that might have a use for the data. The program is easily adaptable to acquire additional data and log that data to disk. The current version also drives displays using precision pitch and roll information to aid the pilot in maintaining a level-level attitude for radar/radiometer mapping beyond the degree available by flying visually or using a standard gyro-driven attitude indicator. The software is designed to acquire an array of data to help the mission manager make real-time decisions as to the effectiveness of the flight. This data is displayed for the mission manager and broadcast to the other experiments on the aircraft for inclusion in their data files. The program also drives real-time precision pitch and roll displays for the pilot and copilot to aid them in maintaining the desired attitude, when required, during data acquisition on mapping lines.

77 FR 68057 - Airworthiness Directives; Sikorsky Aircraft Corporation Helicopters

Science.gov (United States)

2012-11-15

... Airworthiness Directives; Sikorsky Aircraft Corporation Helicopters AGENCY: Federal Aviation Administration (FAA... Sikorsky Aircraft Corporation (Sikorsky) Model S-76C helicopters. This AD requires installing an improved... Corporation, Attn: Manager, Commercial Technical Support, mailstop s581a, 6900 Main Street, Stratford, CT...

A Turbo-Brayton Cryocooler for Aircraft Superconducting Systems, Phase II

Data.gov (United States)

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...

Assessment of aircraft risk reduction at Pantex Plant

International Nuclear Information System (INIS)

Lin, Y.T.; Hedtke, R.; Fike, D.; Diniz, J.

1996-01-01

The possibility of an aircraft crashing into the Department of Energy's (DOE) Pantex plant facility has been of concern in risk assessments. In response to public concerns, and in an effort to reduce risks associated with overflights of Pantex, several changes to navigational aids at Amarillo International Airport have been implemented. For over one year, a radar airspace monitor and recording system has been connected to the airport surveillance radar at Amarillo to record the flight paths, aircraft types, and traffic density of aircraft in the vicinity of the Pantex plant. The data has provided a better understanding of the overflight risk at Pantex as well as a means to measure the effectiveness of risk reduction efforts

Test of prototype liquid-water-content meter for aircraft use

Science.gov (United States)

Gerber, Hermann E.

1993-01-01

This report describes the effort undertaken to meet the objectives of National Science Foundation Grant ATM-9207345 titled 'Test of Prototype Liquid-Water-Content Meter for Aircraft Use.' Three activities were proposed for testing the new aircraft instrument, PVM-100A: (1) Calibrate the PVM-100A in a facility where the liquid-water-content (LWC) channel, and the integrated surface area channel (PSA) could be compared to standard means for LWC and PSA measurements. Scaling constant for the channels were to be determined in this facility. The fog/wind tunnel at ECN, Petten, The Netherlands was judged the most suitable facility for this effort. (2) Expose the PVM-100A to high wind speeds similar to those expected on research aircraft, and test the anti-icing heaters on the PVM-100A under typical icing conditions expected in atmospheric clouds. The high-speed icing tunnel at NRC, Ottawa, Canada was to be utilized. (3) Operate the PVM-100A on an aircraft during cloud penetrations to determine its stability and practicality for such measurements. The C-131A aircraft of the University of Washington was the aircraft of opportunity for these-tests, which were to be conducted during the 4-week Atlantic Stratocumulus Transition Experiment (ASTEX) in June of 1992.

U.S. Geological Survey Unmanned Aircraft Systems (UAS) Roadmap 2014

Science.gov (United States)

Cress, Jill J.; Hutt, Michael E.; Sloan, Jeff L.; Bauer, Mark A.; Feller, Mark R.; Goplen, Susan E.

2015-01-01

The U.S. Department of the Interior (DOI) is responsible for protecting the natural resources and heritage contained on almost 20 percent of the land in the United States. This responsibility requires acquisition of remotely sensed data throughout vast lands, including areas that are remote and potentially dangerous to access. One promising new technology for data collection is unmanned aircraft systems (UAS), which may be better suited (achieving superior science, safety, and savings) than traditional methods. UAS, regardless of their size, have the same operational components: aircraft, payloads, communications unit, and operator control unit. The aircraft is the platform that flies and carries any required payloads. For Department of the Interior missions these payloads will be either a sensor or set of sensors that can acquire the specific type of remotely sensed data that is needed. The aircraft will also carry the payload that is responsible for transmitting live airborne video images, compass headings, and location information to the operator control unit. The communications unit, which transfers information between the aircraft and the operator control unit, consists of the hardware and software required to establish both uplink and downlink communications. Finally, the operator control unit both controls and monitors the aircraft and can be operated either by a pilot on the ground or autonomously.

Aircraft Wake Vortex Deformation in Turbulent Atmosphere

OpenAIRE

Hennemann, Ingo; Holzaepfel, Frank

2007-01-01

Large-scale distortion of aircraft wake vortices appears to play a crucial role for aircraft safety during approach and landing. Vortex distortion is investigated based on large eddy simulations of wake vortex evolution in a turbulent atmosphere. A vortex identification method is developed that can be adapted to the vortex scales of interest. Based on the identified vortex center tracks, a statistics of vortex curvature radii is established. This statistics constitutes the basis for understan...

PIV-based load determination in aircraft propellers

OpenAIRE

Ragni, D.

2012-01-01

The thesis describes the application of particle image velocimetry (PIV) to study the aerodynamic loads of airfoils and aircraft propellers. The experimental work focuses on the development of a measurement procedure to infer the pressure of the flow field from the velocity distribution obtained by PIV velocimetry. The technique offers important advantages in aircraft propellers, since the loads can be locally inspected without the need to install pressure sensors and momentum balances in rot...

X-36 Tailless Fighter Agility Research Aircraft arrival at Dryden

Science.gov (United States)

1996-01-01

The NASA/McDonnell Douglas Corporation (MDC) X-36 Tailless Fighter Agility Research Aircraft in it's hangar at NASA Dryden Flight Research Center, Edwards, California, following its arrival on July 2, 1996. The NASA/Boeing X-36 Tailless Fighter Agility Research Aircraft program successfully demonstrated the tailless fighter design using advanced technologies to improve the maneuverability and survivability of possible future fighter aircraft. The program met or exceeded all project goals. For 31 flights during 1997 at the Dryden Flight Research Center, Edwards, California, the project team examined the aircraft's agility at low speed / high angles of attack and at high speed / low angles of attack. The aircraft's speed envelope reached up to 206 knots (234 mph). This aircraft was very stable and maneuverable. It handled very well. The X-36 vehicle was designed to fly without the traditional tail surfaces common on most aircraft. Instead, a canard forward of the wing was used as well as split ailerons and an advanced thrust-vectoring nozzle for directional control. The X-36 was unstable in both pitch and yaw axes, so an advanced, single-channel digital fly-by-wire control system (developed with some commercially available components) was put in place to stabilize the aircraft. Using a video camera mounted in the nose of the aircraft and an onboard microphone, the X-36 was remotely controlled by a pilot in a ground station virtual cockpit. A standard fighter-type head-up display (HUD) and a moving-map representation of the vehicle's position within the range in which it flew provided excellent situational awareness for the pilot. This pilot-in-the-loop approach eliminated the need for expensive and complex autonomous flight control systems and the risks associated with their inability to deal with unknown or unforeseen phenomena in flight. Fully fueled the X-36 prototype weighed approximately 1,250 pounds. It was 19 feet long and three feet high with a wingspan of

Mathematical Modeling of the Braking System of Wheeled Mainline Aircraft

Directory of Open Access Journals (Sweden)

I. S. Shumilov

2016-01-01

Full Text Available The braking system of the landing gear wheels of a mainline aircraft has to meet mandatory requirements laid out in the Aviation Regulations AP-25 (Para 25.735. «Brakes and brake systems". These requirements are essential when creating the landing gear wheel brake control system (WBCS and are used as main initial data in its mathematical modeling. The WBCS is one of the most important systems to ensure the safe completion of the flight. It is a complex of devices, i.e. units (hydraulic, electrical, and mechanical, connected through piping, wiring, mechanical constraints. This complex should allow optimizing the braking process when a large number of parameters change. The most important of them are the following: runway friction coefficient (RFC, lifting force, weight and of the aircraft, etc. The main structural elements involved in braking the aircraft are: aircraft wheels with pneumatics (air tires and brake discs, WBCS, and cooling system of gear wheels when braking.To consider the aircraft deceleration on the landing run is of essence at the stage of design, development, and improvement of brakes and braking systems. Based on analysis of equation of the aircraft motion and energy balance can be determined energy loading and its basic design parameters, braking distances and braking time.As practice and analysis of energy loading show, they (brake + wheel absorb the aircraftpossessed kinetic energy at the start of braking as much as 60-70%, 70-80%, and 80-90%, respectively, under normal increased, and emergency operating conditions. The paper presents a procedure for the rapid calculation of energy loading of the brake wheel.Currently, the mainline aircrafts use mainly electrohydraulic brake systems in which there are the main, backup, and emergency-parking brake systems. All channels are equipped with automatic anti-skid systems. Their presence in the emergency (the third reserve channel significantly improves the reliability and safety of

Small Engine Technology (SET) Task 24 Business and Regional Aircraft System Studies

Science.gov (United States)

Lieber, Lysbeth

2003-01-01

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.

How Effective Is Communication Training For Aircraft Crews

Science.gov (United States)

Linde, Charlotte; Goguen, Joseph; Devenish, Linda

1992-01-01

Report surveys communication training for aircraft crews. Intended to alleviate problems caused or worsened by poor communication and coordination among crewmembers. Focuses on two training methods: assertiveness training and grid-management training. Examines theoretical background of methods and attempts made to validate their effectiveness. Presents criteria for evaluating applicability to aviation environment. Concludes communication training appropriate for aircraft crews.

The organization closed water battery plant Aircraft Factory

Directory of Open Access Journals (Sweden)

В.М. Ісаєнко

2008-01-01

Full Text Available  The information on unrational water usage and losts is given in the article. The necessity of closed water cycle introduction is shown for the aircraft repairing plant. The principle scheme of closed cycle water usage is developed for the accumulator department of the aircraft repairing plant. Modern technological equipment is offered for implementation.

AEROSTATIC AND AERODYNAMIC MODULES OF A HYBRID BUOYANT AIRCRAFT: AN ANALYTICAL APPROACH

Directory of Open Access Journals (Sweden)

Anwar Ul Haque

2015-05-01

Full Text Available An analytical approach is essential for the estimation of the requirements of aerodynamic and aerostatic lift for a hybrid buoyant aircraft. Such aircrafts have two different modules to balance the weight of aircraft; aerostatic module and aerodynamic module. Both these modules are to be treated separately for estimation of the mass budget of propulsion systems and required power. In the present work, existing relationships of aircraft and airship are reviewed for its further application for these modules. Limitations of such relationships are also disussed and it is precieved that it will provide a strating point for better understanding of design anatomy of such aircraft.

An overview of major aspects of the aircraft impact problem

International Nuclear Information System (INIS)

Kamil, H.; Kost, G.; Sharpe, R.

1978-01-01

The major aspects of the aircraft impact problem are identified and the most relevant topics for future investigations are discussed. The emphasis is on three main topics: modeling techniques, influence of non-linear behavior, and importance of damping in the dynamic structural response analyses for aircraft loading. Results are presented from brief studies involving response of linear and nonlinear simple systems to short-duration impulsive loadings of the aircraft impact type. (Auth.)

Turboelectric Distributed Propulsion in a Hybrid Wing Body Aircraft

Science.gov (United States)

Felder, James L.; Brown, Gerald V.; DaeKim, Hyun; Chu, Julio

2011-01-01

The performance of the N3-X, a 300 passenger hybrid wing body (HWB) aircraft with turboelectric distributed propulsion (TeDP), has been analyzed to see if it can meet the 70% fuel burn reduction goal of the NASA Subsonic Fixed Wing project for N+3 generation aircraft. The TeDP system utilizes superconducting electric generators, motors and transmission lines to allow the power producing and thrust producing portions of the system to be widely separated. It also allows a small number of large turboshaft engines to drive any number of propulsors. On the N3-X these new degrees of freedom were used to (1) place two large turboshaft engines driving generators in freestream conditions to maximize thermal efficiency and (2) to embed a broad continuous array of 15 motor driven propulsors on the upper surface of the aircraft near the trailing edge. That location maximizes the amount of the boundary layer ingested and thus maximizes propulsive efficiency. The Boeing B777-200LR flying 7500 nm (13890 km) with a cruise speed of Mach 0.84 and an 118100 lb payload was selected as the reference aircraft and mission for this study. In order to distinguish between improvements due to technology and aircraft configuration changes from those due to the propulsion configuration changes, an intermediate configuration was included in this study. In this configuration a pylon mounted, ultra high bypass (UHB) geared turbofan engine with identical propulsion technology was integrated into the same hybrid wing body airframe. That aircraft achieved a 52% reduction in mission fuel burn relative to the reference aircraft. The N3-X was able to achieve a reduction of 70% and 72% (depending on the cooling system) relative to the reference aircraft. The additional 18% - 20% reduction in the mission fuel burn can therefore be attributed to the additional degrees of freedom in the propulsion system configuration afforded by the TeDP system that eliminates nacelle and pylon drag, maximizes boundary

A novel control technique for active shunt power filters for aircraft applications

OpenAIRE

Lavopa, Elisabetta

2011-01-01

The More Electric Aircraft is a technological trend in modern aerospace industry to increasingly use electrical power on board the aircraft in place of mechanical, hydraulic and pneumatic power to drive aircraft subsystems. This brings major changes to the aircraft electrical system, increasing the complexity of the network topology together with stability and power quality issues. Shunt active power filters are a viable solution for power quality enhancement, in order to comply with the stan...

Aircraft de-icer: Recycling can cut carbon emissions in half

International Nuclear Information System (INIS)

Johnson, Eric P.

2012-01-01

Flight-safety regulations in most countries require aircraft to be ice-free upon takeoff. In icy weather, this means that the aircraft usually must be de-iced (existing ice is removed) and sometimes anti-iced (to protect against ice-reformation). For both processes, aircraft typically are sprayed with an ‘antifreeze’ solution, consisting mainly of glycol diluted with water. This de/anti-icing creates an impact on the environment, of which environmental regulators have grown increasingly conscious. The US Environmental Protection Agency (EPA), for example, recently introduced stricter rules that require airports above minimum size to collect de-icing effluents and send them to wastewater treatment. De-icer collection and treatment is already done at most major airports, but a few have gone one step further: rather than putting the effluent to wastewater, they recycle it. This study examines the carbon savings that can be achieved by recycling de-icer. There are two key findings. One, recycling, as opposed to not recycling, cuts the footprint of aircraft de-icing by 40–50% — and even more, in regions where electricity-generation is cleaner. Two, recycling petrochemical-based de-icer generates a 15–30% lower footprint than using ‘bio’ de-icer without recycling. - Highlights: ► Carbon footprint of aircraft de-icing can be measured. ► Recycling aircraft de-icer cuts the footprint of aircraft de-icing by 40–50%. ► Recycling ‘fossil’ de-icer is lower carbon than not recycling ‘bio’ de-icer.

76 FR 60367 - Airworthiness Directives; Piper Aircraft, Inc. Airplanes

Science.gov (United States)

2011-09-29

... Airworthiness Directives; Piper Aircraft, Inc. Airplanes AGENCY: Federal Aviation Administration (FAA), DOT. ACTION: Final rule. SUMMARY: We are revising an existing airworthiness directive (AD) for certain Piper...). ADDRESSES: For service information identified in this AD, contact Piper Aircraft, Inc., 2926 Piper Drive...

77 FR 68061 - Airworthiness Directives; Sikorsky Aircraft Corporation Helicopters

Science.gov (United States)

2012-11-15

... Airworthiness Directives; Sikorsky Aircraft Corporation Helicopters AGENCY: Federal Aviation Administration (FAA... Aircraft Corporation (Sikorsky) Model S-92A helicopters. This AD requires inspecting the tail rotor (T/R... Corporation, Attn: Manager, Commercial Technical Support, mailstop s581a, 6900 Main Street, Stratford, CT...

77 FR 18969 - Airworthiness Directives; Sikorsky Aircraft Corporation Helicopters

Science.gov (United States)

2012-03-29

... Corporation Helicopters AGENCY: Federal Aviation Administration (FAA), DOT. ACTION: Notice of proposed... Aircraft Corporation (Sikorsky) Model S-76C helicopters. This proposed AD is prompted by a bird-strike to.... For service information identified in this proposed AD, contact Sikorsky Aircraft Corporation, Attn...

TECHNICAL EFFICIENCY AND TECHNICAL LEVEL INDICATORS APPLICATION FOR CIVIL AIRCRAFT FUNCTIONAL PROPERTIES ANALYSIS

Directory of Open Access Journals (Sweden)

Vadim V. Efimov

2018-01-01

Full Text Available Functional properties characterize the purpose of the aircraft and are described by its flight performance characteristics such as range and cruising speed, payload, runway characteristics, etc. Functional properties also characterize the aircraft efficiency that determines the objective need for their analysis by both aircraft designers and operators in conditions of permanent and systematic efficiency increase necessity. When choosing the aircraft, it is important for the operator to make sure that a selected aircraft type has a high level of functional properties, which will allow it to provide high operational efficiency without obsolescence in the long term. However, when choosing from several aircraft types the operator has to face the fact that some characteristics of considered aircraft variants are better and the others are worse that does not allow to definitely determine what aircraft type has a higher level of functional properties.The possibility of applying technical efficiency indicators and a generalized technical level indicator for analyzing the functional properties of civil aviation aircraft is explored in this article. Fuel, weight and target efficiency values as well as the previously improved technical level indicator value were calculated for the different generations and modifications of Boeing 737 and Airbus A320 families of medium-range airplanes, which was followed by the results interpretation within one airplane generation and when moving historically from one airplane generation to another. According to analysis results it is concluded that it is impossible to define the change of the aircraft functional properties level by the change in the values of separate technical efficiency indicators. Thus, it is proposed to use a generalized technical level indicator that determines the level of aircraft technical perfection for purpose and to use efficiency indicators to analyze the cost of providing this level of

Smart Patches for Monitoring Fatigue Crack Growth in Aircraft Structures

National Research Council Canada - National Science Library

Ihn, Jeong-Beom

2001-01-01

A built-in cost-effective diagnostic system for monitoring crack growth in aircraft structures was developed, particularly for riveted fuselage joints and cracked aircraft parts with composite bonded patches...

A Collection of Nonlinear Aircraft Simulations in MATLAB

Science.gov (United States)

Garza, Frederico R.; Morelli, Eugene A.

2003-01-01

Nonlinear six degree-of-freedom simulations for a variety of aircraft were created using MATLAB. Data for aircraft geometry, aerodynamic characteristics, mass / inertia properties, and engine characteristics were obtained from open literature publications documenting wind tunnel experiments and flight tests. Each nonlinear simulation was implemented within a common framework in MATLAB, and includes an interface with another commercially-available program to read pilot inputs and produce a three-dimensional (3-D) display of the simulated airplane motion. Aircraft simulations include the General Dynamics F-16 Fighting Falcon, Convair F-106B Delta Dart, Grumman F-14 Tomcat, McDonnell Douglas F-4 Phantom, NASA Langley Free-Flying Aircraft for Sub-scale Experimental Research (FASER), NASA HL-20 Lifting Body, NASA / DARPA X-31 Enhanced Fighter Maneuverability Demonstrator, and the Vought A-7 Corsair II. All nonlinear simulations and 3-D displays run in real time in response to pilot inputs, using contemporary desktop personal computer hardware. The simulations can also be run in batch mode. Each nonlinear simulation includes the full nonlinear dynamics of the bare airframe, with a scaled direct connection from pilot inputs to control surface deflections to provide adequate pilot control. Since all the nonlinear simulations are implemented entirely in MATLAB, user-defined control laws can be added in a straightforward fashion, and the simulations are portable across various computing platforms. Routines for trim, linearization, and numerical integration are included. The general nonlinear simulation framework and the specifics for each particular aircraft are documented.

Cryogenic system options for a superconducting aircraft propulsion system

International Nuclear Information System (INIS)

Berg, F; Dodds, Graham; Palmer, J; Bertola, L; Miller, Paul

2015-01-01

There is a perceived need in the future for a move away from traditional aircraft designs in order to meet ambitious emissions and fuel burn targets. High temperature superconducting distributed propulsion may be an enabler for aircraft designs that have better propulsive efficiency and lower drag. There has been significant work considering the electrical systems required, but less on the cryogenics to enable it. This paper discusses some of the major choices to be faced in cryocooling for aircraft. The likely need for a disposable cryogen to reduce power demand is explained. A set of cryocooling methods are considered in a sensitivity study, which shows that the feasibility of the cryogenic system will depend strongly on the superconducting technology and the aircraft platform. It is argued that all three aspects must be researched and designed in close collaboration to reach a viable solution. (paper)

Vehicle Design Evaluation Program (VDEP). A computer program for weight sizing, economic, performance and mission analysis of fuel-conservative aircraft, multibodied aircraft and large cargo aircraft using both JP and alternative fuels

Science.gov (United States)

Oman, B. H.

1977-01-01

The NASA Langley Research Center vehicle design evaluation program (VDEP-2) was expanded by (1) incorporating into the program a capability to conduct preliminary design studies on subsonic commercial transport type aircraft using both JP and such alternate fuels as hydrogen and methane;(2) incorporating an aircraft detailed mission and performance analysis capability; and (3) developing and incorporating an external loads analysis capability. The resulting computer program (VDEP-3) provides a preliminary design tool that enables the user to perform integrated sizing, structural analysis, and cost studies on subsonic commercial transport aircraft. Both versions of the VDEP-3 Program which are designated preliminary Analysis VDEP-3 and detailed Analysis VDEP utilize the same vehicle sizing subprogram which includes a detailed mission analysis capability, as well as a geometry and weight analysis for multibodied configurations.

Structural design for aircraft impact loading

International Nuclear Information System (INIS)

Schmidt, R.; Heckhausen, H.; Chen, C.; Rieck, P.J.; Lemons, G.W.

1977-01-01

The distribution of military aircraft and proximity to commercial air routes requires the analysis of aircraft impact effect on nuclear power plant facilities in Europe. The typical approach on recent projects has been the hardening of safety-related buildings and/or protection of redundant safety-related equipment through separation. The 'hardened-building' approach has led to the consideration of severe shock and vibration caused by the aircraft impact and development of corresponding floor response spectra for component design. Conservatively calculated loads resulting from these are in some cases quite severe. The reactor auxiliary system building (Soft Shell Hardcore design) allows a more defensive alternate in the form of a partially softened design. In this approach the equipment layout is arranged such that equipment performing either safety functions or having the potential for significant release of radioactivity (upon destruction) is located in the central area of the plant and is enclosed in thick concrete walls for shielding and protection purposes. The non-safety class equipment is arranged in the area peripheral to the hardened central area and enclosed in thin concrete walls. Since the kinetic energy of the impacting aircraft is absorbed by the collapsed thin walls and ceilings, the vibrational effect on the safety class equipment is drastically reduced. In order to achieve the objective of absorbing high kinetic energy and yet reduce the shock and vibration effects, the softened exterior walls require low resistance and high ductility. This investigation determines the feasibility of two 0.5 m thick walls of the Soft Shell with the simplest possible mathematical model. (Auth.)

A Cybernetic Approach to Assess the Longitudinal Handling Qualities of Aeroelastic Aircraft

NARCIS (Netherlands)

Damveld, H.J.

2009-01-01

The future demand for larger and lighter civil transport aircraft leads to more flexible aircraft, which bring their own controlling and handling problems. A review of established handling qualities methods showed that they were either unsuitable for aeroelastic aircraft, or had significant

Designing a Robust Nonlinear Dynamic Inversion Controller for Spacecraft Formation Flying

Directory of Open Access Journals (Sweden)

Inseok Yang

2014-01-01

Full Text Available The robust nonlinear dynamic inversion (RNDI control technique is proposed to keep the relative position of spacecrafts while formation flying. The proposed RNDI control method is based on nonlinear dynamic inversion (NDI. NDI is nonlinear control method that replaces the original dynamics into the user-selected desired dynamics. Because NDI removes nonlinearities in the model by inverting the original dynamics directly, it also eliminates the need of designing suitable controllers for each equilibrium point; that is, NDI works as self-scheduled controller. Removing the original model also provides advantages of ease to satisfy the specific requirements by simply handling desired dynamics. Therefore, NDI is simple and has many similarities to classical control. In real applications, however, it is difficult to achieve perfect cancellation of the original dynamics due to uncertainties that lead to performance degradation and even make the system unstable. This paper proposes robustness assurance method for NDI. The proposed RNDI is designed by combining NDI and sliding mode control (SMC. SMC is inherently robust using high-speed switching inputs. This paper verifies similarities of NDI and SMC, firstly. And then RNDI control method is proposed. The performance of the proposed method is evaluated by simulations applied to spacecraft formation flying problem.

Direct carbon dioxide emissions from civil aircraft

OpenAIRE

Grote, Matt; Williams, Ian; Preston, John

2014-01-01

Global airlines consume over 5 million barrels of oil per day, and the resulting carbon dioxide (CO2) emitted by aircraft engines is of concern. This article provides a contemporary review of the literature associated with the measures available to the civil aviation industry for mitigating CO2 emissions from aircraft. The measures are addressed under two categories – policy and legal-related measures, and technological and operational measures. Results of the review are used to develop sever...

Global Tracking Control of Quadrotor VTOL Aircraft in Three-Dimensional Space

Directory of Open Access Journals (Sweden)

Duc Khac Do

2014-07-01

Full Text Available This paper presents a method to design controllers that force a quadrotor vertical take-off and landing (VTOL aircraft to globally asymptotically track a reference trajectory in three-dimensional space. Motivated by the vehicle's steering practice, the roll and pitch angles are considered as immediate controls plus the total thrust force  provided by the aircraft's four rotors to control the position and yaw angle of the aircraft. The control design is based on the newly introduced one-step ahead backstepping, the standard backstepping and Lyapunov's direct methods. A combination of Euler angles and unit-quaternion for the attitude representation of the aircraft is used to obtain global tracking control results. The paper also includes a design of observers that exponentially estimate the aircraft's linear velocity vector and disturbances. Simulations illustrate the results.

77 FR 55770 - Airworthiness Directives; Cessna Aircraft Company Airplanes

Science.gov (United States)

2012-09-11

... aircraft's hydraulic power pack wiring for incorrect installation, and if needed, correct the installation... this AD, whichever occurs first, inspect the hydraulic power pack wiring for correct installation...) Correct the Installation of the Hydraulic Power Pack Wiring (1) Single engine aircraft: If you find...

Decay or collapse: Aircraft wake vortices in grid turbulence

NARCIS (Netherlands)

Ren, M.; Elsenaar, A.; van Heijst, G.J.F.; Kuczaj, Arkadiusz K.; Geurts, Bernardus J.

2006-01-01

Trailing vortices are naturally shed by airplanes and they typically evolve into a counter-rotating vortex pair. Downstream of the aircraft, these vortices can persist for a very long time and extend for several kilometers. This poses a potential hazard to following aircraft, particularly during

A comparison of Probability Of Detection (POD) data determined using different statistical methods

Science.gov (United States)

Fahr, A.; Forsyth, D.; Bullock, M.

1993-12-01

Different statistical methods have been suggested for determining probability of detection (POD) data for nondestructive inspection (NDI) techniques. A comparative assessment of various methods of determining POD was conducted using results of three NDI methods obtained by inspecting actual aircraft engine compressor disks which contained service induced cracks. The study found that the POD and 95 percent confidence curves as a function of crack size as well as the 90/95 percent crack length vary depending on the statistical method used and the type of data. The distribution function as well as the parameter estimation procedure used for determining POD and the confidence bound must be included when referencing information such as the 90/95 percent crack length. The POD curves and confidence bounds determined using the range interval method are very dependent on information that is not from the inspection data. The maximum likelihood estimators (MLE) method does not require such information and the POD results are more reasonable. The log-logistic function appears to model POD of hit/miss data relatively well and is easy to implement. The log-normal distribution using MLE provides more realistic POD results and is the preferred method. Although it is more complicated and slower to calculate, it can be implemented on a common spreadsheet program.

Study of aircraft electrical power systems

Science.gov (United States)

1972-01-01

The formulation of a philosophy for devising a reliable, efficient, lightweight, and cost effective electrical power system for advanced, large transport aircraft in the 1980 to 1985 time period is discussed. The determination and recommendation for improvements in subsystems and components are also considered. All aspects of the aircraft electrical power system including generation, conversion, distribution, and utilization equipment were considered. Significant research and technology problem areas associated with the development of future power systems are identified. The design categories involved are: (1) safety-reliability, (2) power type, voltage, frequency, quality, and efficiency, (3) power control, and (4) selection of utilization equipment.

Aircraft gas turbine engine vibration diagnostics

Directory of Open Access Journals (Sweden)

Stanislav Fábry

2017-11-01

Full Text Available In the Czech and Slovak aviation are in service elderly aircrafts, usually produced in former Soviet Union. Their power units can be operated in more efficient way, in case of using additional diagnostic methods that allow evaluating their health. Vibration diagnostics is one of the methods indicating changes of rotational machine dynamics. Ground tests of aircraft gas turbine engines allow vibration recording and analysis. Results contribute to airworthiness evaluation and making corrections, if needed. Vibration sensors distribution, signal recording and processing are introduced in a paper. Recorded and re-calculated vibration parameters are used in role of health indicators.

Aircraft Flight Modeling During the Optimization of Gas Turbine Engine Working Process

Science.gov (United States)

Tkachenko, A. Yu; Kuz'michev, V. S.; Krupenich, I. N.

2018-01-01

The article describes a method for simulating the flight of the aircraft along a predetermined path, establishing a functional connection between the parameters of the working process of gas turbine engine and the efficiency criteria of the aircraft. This connection is necessary for solving the optimization tasks of the conceptual design stage of the engine according to the systems approach. Engine thrust level, in turn, influences the operation of aircraft, thus making accurate simulation of the aircraft behavior during flight necessary for obtaining the correct solution. The described mathematical model of aircraft flight provides the functional connection between the airframe characteristics, working process of gas turbine engines (propulsion system), ambient and flight conditions and flight profile features. This model provides accurate results of flight simulation and the resulting aircraft efficiency criteria, required for optimization of working process and control function of a gas turbine engine.

A Risk Management Architecture for Emergency Integrated Aircraft Control

Science.gov (United States)

McGlynn, Gregory E.; Litt, Jonathan S.; Lemon, Kimberly A.; Csank, Jeffrey T.

2011-01-01

Enhanced engine operation--operation that is beyond normal limits--has the potential to improve the adaptability and safety of aircraft in emergency situations. Intelligent use of enhanced engine operation to improve the handling qualities of the aircraft requires sophisticated risk estimation techniques and a risk management system that spans the flight and propulsion controllers. In this paper, an architecture that weighs the risks of the emergency and of possible engine performance enhancements to reduce overall risk to the aircraft is described. Two examples of emergency situations are presented to demonstrate the interaction between the flight and propulsion controllers to facilitate the enhanced operation.

Load event: Aircraft crash

International Nuclear Information System (INIS)

Fritsch, H.

1985-01-01

The bibliography includes 48 quotations, up to the year 1983, on the following issues: Experiments and computational methods. Design load for the dimensioning of reinforced concrete buildings and components with respect to the dynamic load in the event of an aircraft crash. (orig./HP) [de

Enhancing Combat Survivability of Existing Unmanned Aircraft Systems

Science.gov (United States)

2008-12-01

1 With efforts underway to develop rules integrating UAS’s into the National Airspace System, and...realizing that Federal Aviation Administration rule -making authority applied only to "aircraft," the term Remotely Operated Aircraft (ROA) was coined in...http://www.af.mil/factsheets/factsheet.asp?id=122 [10] Peter La Franchi , “US study recommends self-protection for UAVs”, Flight International, 7

Structural Health Monitoring of Transport Aircraft with Fuzzy Logic Modeling

Directory of Open Access Journals (Sweden)

Ray C. Chang

2013-01-01

Full Text Available A structural health monitoring method based on the concept of static aeroelasticity is presented in this paper. This paper focuses on the estimation of these aeroelastic effects on older transport aircraft, in particular the structural components that are most affected, in severe atmospheric turbulence. Because the structural flexibility properties are mostly unknown to aircraft operators, only the trend, not the magnitude, of these effects is estimated. For this purpose, one useful concept in static aeroelastic effects for conventional aircraft structures is that under aeroelastic deformation the aerodynamic center should move aft. This concept is applied in the present paper by using the fuzzy-logic aerodynamic models. A twin-jet transport aircraft in severe atmospheric turbulence involving plunging motion is examined. It is found that the pitching moment derivatives in cruise with moderate to severe turbulence in transonic flight indicate some degree of abnormality in the stabilizer (i.e., the horizontal tail. Therefore, the horizontal tail is the most severely affected structural component of the aircraft probably caused by vibration under the dynamic loads induced by turbulence.

Design of adaptive switching control for hypersonic aircraft

Directory of Open Access Journals (Sweden)

Xin Jiao

2015-10-01

Full Text Available This article proposes a novel adaptive switching control of hypersonic aircraft based on type-2 Takagi–Sugeno–Kang fuzzy sliding mode control and focuses on the problem of stability and smoothness in the switching process. This method uses full-state feedback to linearize the nonlinear model of hypersonic aircraft. Combining the interval type-2 Takagi–Sugeno–Kang fuzzy approach with sliding mode control keeps the adaptive switching process stable and smooth. For rapid stabilization of the system, the adaptive laws use a direct constructive Lyapunov analysis together with an established type-2 Takagi–Sugeno–Kang fuzzy logic system. Simulation results indicate that the proposed control scheme can maintain the stability and smoothness of switching process for the hypersonic aircraft.

Airport acoustics: Aircraft noise distribution and modelling of some ...

African Journals Online (AJOL)

Airport acoustics: Aircraft noise distribution and modelling of some aircraft parameters. MU Onuu, EO Obisung. Abstract. No Abstract. Nigerian Journal of Physics Vol. 17 (Supplement) 2005: pp. 177-186. Full Text: EMAIL FREE FULL TEXT EMAIL FREE FULL TEXT · DOWNLOAD FULL TEXT DOWNLOAD FULL TEXT.

78 FR 57104 - Airworthiness Directives; Diamond Aircraft Industries Airplanes

Science.gov (United States)

2013-09-17

... p.m., Monday through Friday, except Federal holidays. For service information identified in this... AD docket. Relevant Service Information Diamond Aircraft Industries GmbH has issued Mandatory Service... service information related to this AD, contact Diamond Aircraft Industries GmbH, N.A. Otto-Str.5, A-2700...

Resistance ability evaluation of safety-related structures for the simulated aircraft accident

Energy Technology Data Exchange (ETDEWEB)

Kim, Young Jin; Kim, Sung Woon; Choi, Jang Kyu [Daewoo E and C Co., Ltd., Suwon (Korea, Republic of)] (and others)

2003-03-15

Aircraft accidents on nuclear safety-related structures can cause severe damage to the safety of NPP(Nuclear Power Plant)s. To assess the safety of nuclear safety-related structures, the local damage and the dynamic response of global structures should be investigated together. This study have compared several local damage assessment formulas suggested for aircraft as an impactor, and have set the assessment system of local damage for impact-proof design of NPP containment buildings. And the local damage of nuclear safety-related structures in operation in Korea for commercial aircraft as impactor have been estimated. Impact load-time functions of the aircraft crash have been decided to assessment the safety of nuclear safety-related structures against the intentional colliding of commercial aircraft. Boeing 747 and Boeing 767 is selected as target aircraft based on the operation frequencies and weights. Comparison of the fire analysis methods showed that the method considering heat convection and radiation is adequate for the temperature analysis of the aircraft fuel fire. Finally, the study covered the analysis of the major structural drawings and design drawings with which three-dimensional finite element model analysis is expected to be performed.

Rapid evaluation of buildings and infrastructure to accidental and deliberate aircraft impact

International Nuclear Information System (INIS)

Tennant, D.; Levine, H.; Mould, J.; Vaughan, D.

2014-01-01

Recent events involving the impact of large transport aircraft such as the Boeing 767 and 757 into the World Trade Center Towers and the Pentagon have revealed the vulnerability of such structures to terrorist attack. Incidents involving smaller general aviation aircraft have shown the damage that this class of plane can do beyond a protected perimeter. These incidents have elicited inquiries with regard to the effects of impacts of these aircraft types into other critical facilities including aboveground and below ground storage facilities, nuclear power plants, damns and other military and civilian installations. A significant capability to evaluate these threats has been developed during the past 10 years. Small medium and large aircraft have been impacted into buried and aboveground reinforced concrete and light steel frame storage facilities. Both explicit aircraft models and Riera functions (a simplified aircraft impact loading function) have been used to generate an extensive data base. The effects of engines impacting have been studied separately as penetrators. Illustrated in this paper is validation of computational tools for impacts into structures and the initial development of a generalized evaluation tool for rapid evaluation of threats and consequence of aircraft impact into protected facilities

Rapid evaluation of buildings and infrastructure to accidental and deliberate aircraft impact

Energy Technology Data Exchange (ETDEWEB)

Tennant, D., E-mail: tennant@wai.com [Weidlinger Associates, Inc., 6301 Indian School Road NE, Suite 501, Albuquerque, NM 87122 (United States); Levine, H., E-mail: levine@ca.wai.com [Weidlinger Associates, Inc., 399 W. El Camino Real, Suite 200, Mountain View, CA 94040 (United States); Mould, J.; Vaughan, D. [Weidlinger Associates, Inc., 399 W. El Camino Real, Suite 200, Mountain View, CA 94040 (United States)

2014-04-01

Recent events involving the impact of large transport aircraft such as the Boeing 767 and 757 into the World Trade Center Towers and the Pentagon have revealed the vulnerability of such structures to terrorist attack. Incidents involving smaller general aviation aircraft have shown the damage that this class of plane can do beyond a protected perimeter. These incidents have elicited inquiries with regard to the effects of impacts of these aircraft types into other critical facilities including aboveground and below ground storage facilities, nuclear power plants, damns and other military and civilian installations. A significant capability to evaluate these threats has been developed during the past 10 years. Small medium and large aircraft have been impacted into buried and aboveground reinforced concrete and light steel frame storage facilities. Both explicit aircraft models and Riera functions (a simplified aircraft impact loading function) have been used to generate an extensive data base. The effects of engines impacting have been studied separately as penetrators. Illustrated in this paper is validation of computational tools for impacts into structures and the initial development of a generalized evaluation tool for rapid evaluation of threats and consequence of aircraft impact into protected facilities.

Advanced organic composite materials for aircraft structures: Future program

Science.gov (United States)

1987-01-01

Revolutionary advances in structural materials have been responsible for revolutionary changes in all fields of engineering. These advances have had and are still having a significant impact on aircraft design and performance. Composites are engineered materials. Their properties are tailored through the use of a mix or blend of different constituents to maximize selected properties of strength and/or stiffness at reduced weights. More than 20 years have passed since the potentials of filamentary composite materials were identified. During the 1970s much lower cost carbon filaments became a reality and gradually designers turned from boron to carbon composites. Despite progress in this field, filamentary composites still have significant unfulfilled potential for increasing aircraft productivity; the rendering of advanced organic composite materials into production aircraft structures was disappointingly slow. Why this is and research and technology development actions that will assist in accelerating the application of advanced organic composites to production aircraft is discussed.

Numerical analyses of an aircraft crash on containment building

Energy Technology Data Exchange (ETDEWEB)

Sim, Jae Min; Kim, Seung Hyun; Chang, Yoon Suk [Kyunghee University, Yongin (Korea, Republic of)

2016-05-15

The containment building is responsible to isolate and protect internal devices against external conditions like earthquake, hurricane and impact loading. It has also to protect leakage of radioactivity, like LOCA (Loss Of Coolant Accident), when severe accidents occurred. Meanwhile, social awareness such as terrorism has been increased globally after international aircraft crashes at World Trade Center and Pentagon. In this paper, FE (Finite Element) analyses according to variation of crash locations and speeds were carried out to examine the aircraft crash impact on a domestic containment building. In this paper, numerical analyses of aircraft crash on NPP's containment building were performed taking into account different locations and aircraft speeds. (1) Amounts of concrete failure were dependent on the crash locations and the connector was the most delicate location comparing to the dome and wall part. (2) Maximum stress values generated at the liner plate and rebars did not exceed their UTS values.

Numerical analyses of an aircraft crash on containment building

International Nuclear Information System (INIS)

Sim, Jae Min; Kim, Seung Hyun; Chang, Yoon Suk

2016-01-01

The containment building is responsible to isolate and protect internal devices against external conditions like earthquake, hurricane and impact loading. It has also to protect leakage of radioactivity, like LOCA (Loss Of Coolant Accident), when severe accidents occurred. Meanwhile, social awareness such as terrorism has been increased globally after international aircraft crashes at World Trade Center and Pentagon. In this paper, FE (Finite Element) analyses according to variation of crash locations and speeds were carried out to examine the aircraft crash impact on a domestic containment building. In this paper, numerical analyses of aircraft crash on NPP's containment building were performed taking into account different locations and aircraft speeds. (1) Amounts of concrete failure were dependent on the crash locations and the connector was the most delicate location comparing to the dome and wall part. (2) Maximum stress values generated at the liner plate and rebars did not exceed their UTS values