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Sample records for aircraft strike hazard

  1. Abundance of diurnal raptors in relation to prairie dog colonies: Implications for bird-aircraft strike hazard

    USGS Publications Warehouse

    Merriman, J.W.; Boal, C.W.; Bashore, T.L.; Zwank, P.J.; Wester, D.B.

    2007-01-01

    Some diurnal raptors are frequently observed at prairie dog (Cynomys sp.) colonies. As a result, some military installations have conducted prairie dog control activities to reduce the bird-aircraft strike hazard (BASH) potential of low-flying aircraft. To evaluate the validity of this management strategy, we assessed raptor associations with prairie dog colonies at 2 short-grass prairie study areas: southern Lubbock County, Texas, USA, and Melrose Bombing and Gunnery Range in east-central New Mexico, USA. We quantified diurnal raptors (i.e., Falconiformes) at plots occupied (colony plots) and unoccupied (noncolony plots) by black-tailed prairie dogs (Cynomys ludovicianus) at both sites throughout 2002. We compared the number of individual birds of a given species at colony and noncolony plots within each study area by season. Ferruginous hawks (Buteo regalis) and northern harriers (Circus cyaneus) were more abundant at colony plots, whereas Swainson's hawks (B. swainsoni) and American kestrels (Falco sparverius) were more abundant at noncolony plots. Red-tailed hawk (B. jamaicensis) abundance did not differ between the 2 plot types. Our results suggest prairie dog control as a method of reducing BASH potential may be effective at some sites but may be ineffective or even increase the BASH potential at others. Thus, bird-avoidance models assessing the BASH potential should be conducted on a site-specific basis using information on relative and seasonal abundances of individual raptor species and the relative strike risks they pose to aircraft.

  2. IDENTIFICATION OF AIRCRAFT HAZARDS

    SciTech Connect

    K.L. Ashley

    2005-03-23

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

  3. Identification of Aircraft Hazards

    SciTech Connect

    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).

  4. Tsunami Hazards From Strike-Slip Earthquakes

    NASA Astrophysics Data System (ADS)

    Legg, M. R.; Borrero, J. C.; Synolakis, C. E.

    2003-12-01

    Strike-slip faulting is often considered unfavorable for tsunami generation during large earthquakes. Although large strike-slip earthquakes triggering landslides and then generating substantial tsunamis are now recognized hazards, many continue to ignore the threat from submarine tectonic displacement during strike-slip earthquakes. Historical data record the occurrence of tsunamis from strike-slip earthquakes, for example, 1906 San Francisco, California, 1994 Mindoro, Philippines, and 1999 Izmit, Turkey. Recognizing that strike-slip fault zones are often curved and comprise numerous en echelon step-overs, we model tsunami generation from realistic strike-slip faulting scenarios. We find that tectonic seafloor uplift, at a restraining bend or"pop-up" structure, provides an efficient mechanism to generate destructive local tsunamis; likewise for subsidence at divergent pull-apart basin structures. Large earthquakes on complex strike-slip fault systems may involve both types of structures. The California Continental Borderland is a high-relief submarine part of the active Pacific-North America transform plate boundary. Natural harbors and bays created by long term vertical motion associated with strike-slip structural irregularities are now sites of burgeoning population and major coastal infrastructure. Significant local tsunamis generated by large strike-slip earthquakes pose a serious, and previously unrecognized threat. We model several restraining bend pop-up structures offshore southern California to quantify the local tsunami hazard. Maximum runup derived in our scenarios ranges from one to several meters, similar to runup observed from the 1994 Mindoro, Philippines, (M=7.1) earthquake. The runup pattern is highly variable, with local extremes along the coast. We only model the static displacement field for the strike-slip earthquake source; dynamic effects of moving large island or submerged banks laterally during strike-slip events remains to be examined

  5. Lightning as an Aircraft Hazard: (Latest citations from the Aerospace Database)

    NASA Technical Reports Server (NTRS)

    1997-01-01

    The bibliography contains citations concerning lightning strikes as an aircraft hazard. Aircraft designs to prevent or withstand lightning strikes, statistics on lightning strikes of aircraft, detection of strikes, remote monitoring and detection of lightning, initiation of lightning strikes by aircraft, effects of lightning strikes on aircraft structural and electronic components, modeling, and simulation of lightning strikes on aircraft are discussed. Remote detection of storms with regard to aircraft safety are discussed in another bibliography. (Contains 50-250 citations and includes a subject term index and title list.)

  6. Analysis of direct and nearby lightning strike data for aircraft

    NASA Technical Reports Server (NTRS)

    Giri, D. V.; Noss, R. S.; Phuoc, D. B.; Tesche, F. M.

    1983-01-01

    A method for interpreting direct strike and nearby strike lightning data on aircraft is discussed. The theoretical basis for the interpretation involves a transmission line model for the aircraft, and is discussed. Results of applying this model to the F-106 aircraft are presented and in the natural resonances are computed for several different electrical representations of the aircraft. The signal processing techniques useful for extracting pole (resonance) information from experimental data are discussed, and the use of these techniques on the measured lightning data is illustrated. Finally, the results of a related ground-based lightning experiment are discussed and data are presented. The purpose of this test was to gain additional understanding of the resonance properties of the F-106 aircraft.

  7. Ranking the risk of wildlife species hazardous to military aircraft

    USGS Publications Warehouse

    Zakrajsek, E.J.; Bissonette, J.A.

    2005-01-01

    Collisions between birds and aircraft (birdstrikes) pose a major threat to aviation safety. Different species pose different levels of threat; thus, identification of the most hazardous species can help managers identify the level of hazard and prioritize mitigation efforts. Dolbeer et al. (2000) assessed the hazard posed by birds to civilian aircraft by analyzing data from the Federal Aviation Administration's (FAA) Wildlife Strike Database to rank the hazardous species and species groups. A similar analysis has not been done for the military but would be useful and necessary. Military flight characteristics differ from those of civilian flights. During the period 1985-1998, birdstrikes cost the United States Air Force (USAF) an average of $35 million/year in damage. Using the USAF Birdstrike Database, we selected and evaluated each species or species group by the number of strikes recorded in each of 3 damage categories. We weighted damage categories to reflect extent and cost of damage. The USAF Birdstrike Database contained 25,519 records of wildlife strikes in the United States. During the period 1985-1998, 22 (mean = 1.6/year) Class-A birdstrikes (>$1,000,000 damage, loss of aircraft, loss of life, or permanent total disability) were sustained, accounting for 80% of total monetary losses caused by birds. Vultures (Cathartes aura, Coragyps atratus, Caracara cheriway) were ranked the most hazardous species group (Hazard Index Rank [HIR] = 127) to USAF aircraft, followed by geese (Branta canadensis, Chen caerulescens, HIR = 76), pelicans (Pelecanus erythrorhynchos, P. occidentalis, HIR = 47), and buteos (Buteo sp., HIR = 30). Of the smaller flocking birds, blackbirds and starlings (mostly Agelaius phoeniceus, Euphagus cyanocephalus, Molothrus ater, Sturnus vulgaris, HIR = 46), horned larks (Eremophila alpestris, HIR = 24), and swallows (Families Hirundinidae, Apodidae, HIR = 23) were species groups ranked highest. Coupling these results with local bird census

  8. A Study of Aircraft Fire Hazards Related to Natural Electrical Phenomena

    NASA Technical Reports Server (NTRS)

    Kester, Frank L.; Gerstein, Melvin; Plumer, J. A.

    1960-01-01

    The problems of natural electrical phenomena as a fire hazard to aircraft are evaluated. Assessment of the hazard is made over the range of low level electrical discharges, such as static sparks, to high level discharges, such as lightning strikes to aircraft. In addition, some fundamental work is presented on the problem of flame propagation in aircraft fuel vent systems. This study consists of a laboratory investigation in five parts: (1) a study of the ignition energies and flame propagation rates of kerosene-air and JP-6-air foams, (2) a study of the rate of flame propagation of n-heptane, n-octane, n-nonane, and n-decane in aircraft vent ducts, (3) a study of the damage to aluminum, titanium, and stainless steel aircraft skin materials by lightning strikes, (4) a study of fuel ignition by lightning strikes to aircraft skins, and (5) a study of lightning induced flame propagation in an aircraft vent system.

  9. The 1981 direct strike lightning data. [utilizing the F-106 aircraft

    NASA Technical Reports Server (NTRS)

    Pitts, F. L.; Thomas, M. E.

    1982-01-01

    Data waveforms obtained during the 1981 direct strike lightning tests, utilizing the NASA F-106B aircraft specially instrumented for lightning electromagnetic measurements are presented. The aircraft was operated in a thunderstorm environment to elicit strikes. Electromagnetic field data were recorded for both attached lightning and free field excitation of the aircraft.

  10. Evaluating fault rupture hazard for strike-slip earthquakes

    USGS Publications Warehouse

    Petersen, M.; Cao, T.; Dawson, Tim; Frankel, A.; Wills, C.; Schwartz, D.

    2004-01-01

    We present fault displacement data, regressions, and a methodology to calculate in both a probabilistic and deterministic framework the fault rupture hazard for strike-slip faults. To assess this hazard we consider: (1) the size of the earthquake and probability that it will rupture to the surface, (2) the rate of all potential earthquakes on the fault (3) the distance of the site along and from the mapped fault, (4) the complexity of the fault and quality of the fault mapping, (5) the size of the structure that will be placed at the site, and (6) the potential and size of displacements along or near the fault. Probabilistic fault rupture hazard analysis should be an important consideration in design of structures or lifelines that are located within about 50m of well-mapped active faults.

  11. Fault displacement hazard for strike-slip faults

    USGS Publications Warehouse

    Petersen, M.D.; Dawson, T.E.; Chen, R.; Cao, T.; Wills, C.J.; Schwartz, D.P.; Frankel, A.D.

    2011-01-01

    In this paper we present a methodology, data, and regression equations for calculating the fault rupture hazard at sites near steeply dipping, strike-slip faults. We collected and digitized on-fault and off-fault displacement data for 9 global strikeslip earthquakes ranging from moment magnitude M 6.5 to M 7.6 and supplemented these with displacements from 13 global earthquakes compiled byWesnousky (2008), who considers events up to M 7.9. Displacements on the primary fault fall off at the rupture ends and are often measured in meters, while displacements on secondary (offfault) or distributed faults may measure a few centimeters up to more than a meter and decay with distance from the rupture. Probability of earthquake rupture is less than 15% for cells 200 m??200 m and is less than 2% for 25 m??25 m cells at distances greater than 200mfrom the primary-fault rupture. Therefore, the hazard for off-fault ruptures is much lower than the hazard near the fault. Our data indicate that rupture displacements up to 35cm can be triggered on adjacent faults at distances out to 10kmor more from the primary-fault rupture. An example calculation shows that, for an active fault which has repeated large earthquakes every few hundred years, fault rupture hazard analysis should be an important consideration in the design of structures or lifelines that are located near the principal fault, within about 150 m of well-mapped active faults with a simple trace and within 300 m of faults with poorly defined or complex traces.

  12. The microburst - Hazard to aircraft

    NASA Technical Reports Server (NTRS)

    Mccarthy, J.; Serafin, R.

    1984-01-01

    In encounters with microbursts, low altitude aircraft first encounter a strong headwind which increases their wing lift and altitude; this phenomenon is followed in short succession by a decreasing headwind component, a downdraft, and finally a strong tailwind that catastrophically reduces wing lift and precipitates a crash dive. It is noted that the potentially lethal low altitude wind shear of a microburst may lie in apparently harmless, rain-free air beneath a cloud base. Occasionally, such tell-tale signs as localized blowing of ground dust may be sighted in time. Microbursts may, however, occur in the heavy rain of a thunderstorm, where they will be totally obscured from view. Wind shear may be detected by an array of six anemometers and vanes situated in the vicinity of an airport, and by Doppler radar equipment at the airport or aboard aircraft.

  13. FD-TD numerical simulation of an entire lightning strike on the C160 aircraft

    NASA Technical Reports Server (NTRS)

    Alliot, J. C.; Grando, J.; Muller, J. D.; Ferrieres, X.

    1991-01-01

    Experimental transient electromagnetic field measurements were performed on a Transall C160 aircraft during in-flight lightning strikes. The data allow a test of the predictive capabilities of a three dimensional time domain finite difference code (ALICE) developed at ONERA in order to investigate lightning-aircraft interactions. Using a transfer function technique in the 3D code, it is shown that a bi-leader attached to an aircraft can be simulated by a linear model, and so the electromagnetic fields can be calculated anywhere on the vehicle. Comparison of experimental and numerical results were made for several lightning strikes. Skin current density and electromagnetic field distributions are discussed in detail.

  14. Investigation of severe lightning strike incidents to two USAF F-106A aircraft

    NASA Technical Reports Server (NTRS)

    Plumer, J. A.

    1981-01-01

    The results of the inspection and analysis of two F-106A aircraft that were struck by separate lightning strikes within a few minutes of each other are presented. Each aircraft sustained severe lightning strikes to the pitot booms, resulting in extensive damage to the pitot heater power harness, number 8 ground wire, and lightning suppressors, but there was no damage to either aircraft's electrical or avionic systems. A simulated lightning current of 226 kA and 3.8 million A(2)*S was required to reproduce the damage to the ground wires in the radomes. Photographs and detailed assessments of the damage are included.

  15. Wind shear modeling for aircraft hazard definition

    NASA Technical Reports Server (NTRS)

    Frost, W.; Camp, D. W.; Wang, S. T.

    1978-01-01

    Mathematical models of wind profiles were developed for use in fast time and manned flight simulation studies aimed at defining and eliminating these wind shear hazards. A set of wind profiles and associated wind shear characteristics for stable and neutral boundary layers, thunderstorms, and frontal winds potentially encounterable by aircraft in the terminal area are given. Engineering models of wind shear for direct hazard analysis are presented in mathematical formulae, graphs, tables, and computer lookup routines. The wind profile data utilized to establish the models are described as to location, how obtained, time of observation and number of data points up to 500 m. Recommendations, engineering interpretations and guidelines for use of the data are given and the range of applicability of the wind shear models is described.

  16. Deaths and injuries as a result of lightning strikes to aircraft.

    PubMed

    Cherington, M; Mathys, K

    1995-07-01

    Aircraft are at risk of being struck by lightning or triggering lightning as they fly through clouds. Commercial and private airplanes have been struck, with resultant deaths and injuries to passengers and crew. We were interested in learning how large a problem existed to the American public from lightning strikes to airplanes. We analyzed data from the National Transportation Safety Board (NTSB) on lightning-related accidents in the United States from 1963-89. NTSB recorded 40 lightning-related aircraft accidents. There were 10 commercial airplane accidents reported, 4 of which were associated with 260 fatalities and 28 serious injuries. There were 30 private aircraft accidents that accounted for 30 fatalities and 46 serious injuries. While lightning remains a potential risk to aircraft passengers and crew, modern airplanes are better equipped to lessen the dangers of accidents due to lightning. PMID:7575320

  17. Analysis of electromagnetic fields on an F-106B aircraft during lightning strikes

    NASA Technical Reports Server (NTRS)

    Trost, T. F.; Pitts, F. L.

    1982-01-01

    Information on the exterior electromagnetic environment of an aircraft when it is struck by lightning has been obtained during thunderstorm penetrations with an F-106B aircraft. Electric and magnetic fields were observed, using mainly time-derivative type sensors, with bandwidths to 50 MHz. Lightning pulse lengths ranging from 25 ns to 7 microsec have been recorded. Sufficient high-frequency content was present to excite electromagnetic resonances of the aircraft, and peaks in the frequency spectra of the waveforms in the range 7 to 23 MHz are in agreement with the resonant frequencies determined in laboratory scale-model tests. Both positively and negatively charged strikes were experienced, and most of the data suggest low values of peak current.

  18. Frequency Analysis of Aircraft hazards for License Application

    SciTech Connect

    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.

  19. RF radiation from lightning correlated with aircraft measurements during storm hazards-82

    NASA Technical Reports Server (NTRS)

    Levine, D. M.

    1983-01-01

    During the Storm Hazards Experiment 1982, the Goddard Space Flight Center monitored radiation from lightning from a site at the Wallops Flight Facility, Wallops Island, VA. Measurements were made while the NASA F106 penetrated thunderstorms to obtain data on lightning strikes to the aircraft. The objective of the ground-based measurements was to help determine if the events recorded by the F106 were part of lightning discharges. During the experiment, 53 cases were obtained in which events were recorded aboard the aircraft while reliable quality RF radiation was recorded on the ground. These cases came from 12 different storms occurring from June through August 1982. The data confirms that the aircraft was measuring events which were part of lightning and indicates that the events recorded on the aircraft tend to occur early in the flash.

  20. Preliminary Considerations for Classifying Hazards of Unmanned Aircraft Systems

    NASA Technical Reports Server (NTRS)

    Hayhurst, Kelly J.; Maddalon, Jeffrey M.; Miner, Paul S.; Szatkowski, George N.; Ulrey, Michael L.; DeWalt, Michael P.; Spitzer, Cary R.

    2007-01-01

    The use of unmanned aircraft in national airspace has been characterized as the next great step forward in the evolution of civil aviation. To make routine and safe operation of these aircraft a reality, a number of technological and regulatory challenges must be overcome. This report discusses some of the regulatory challenges with respect to deriving safety and reliability requirements for unmanned aircraft. In particular, definitions of hazards and their classification are discussed and applied to a preliminary functional hazard assessment of a generic unmanned system.

  1. Development and application of linear and nonlinear methods for interpretation of lightning strikes to in-flight aircraft

    NASA Technical Reports Server (NTRS)

    Rudolph, Terence; Perala, Rodney A.; Easterbrook, Calvin C.; Parker, Steven L.

    1986-01-01

    Since 1980, NASA has been collecting direct strike lightning data by flying an instrumented F-106B aircraft into thunderstorms. The continuing effort to interpret the measured data is reported here. Both linear and nonlinear finite difference modeling techniques are applied to the problem of lightning triggered by an aircraft in a thunderstorm. Five different aircraft are analyzed to determine the effect of aircraft size and shape on lightning triggering. The effect of lightning channel impedance on aircraft response is investigated. The particle environment in thunderstorms and electric field enhancements by typical ice particles is also investigated.

  2. Progress Towards the Remote Sensing of Aircraft Icing Hazards

    NASA Technical Reports Server (NTRS)

    Reehorst, Andrew; Brinker, David; Politovich, Marcia; Serke, David; Ryerson, Charles; Pazmany, Andrew; Solheim, Fredrick

    2009-01-01

    NASA has teamed with the FAA, DoD, industry, and academia for research into the remote detection and measurement of atmospheric conditions leading to aircraft icing hazards. The ultimate goal of this effort is to provide pilots, controllers, and dispatchers sufficient information to allow aircraft to avoid or minimize their exposure to the hazards of in-flight icing. Since the hazard of in-flight icing is the outcome of aircraft flight through clouds containing supercooled liquid water and strongly influenced by the aircraft s speed and configuration and by the length of exposure, the hazard cannot be directly detected, but must be inferred based upon the measurement of conducive atmospheric conditions. Therefore, icing hazard detection is accomplished through the detection and measurement of liquid water in regions of measured sub-freezing air temperatures. The icing environment is currently remotely measured from the ground with a system fusing radar, lidar, and multifrequency microwave radiometer sensors. Based upon expected ice accretion severity for the measured environment, a resultant aircraft hazard is then calculated. Because of the power, size, weight, and view angle constraints of airborne platforms, the current ground-based solution is not applicable for flight. Two current airborne concepts are based upon the use of either multifrequency radiometers or multifrequency radar. Both ground-based and airborne solutions are required for the future since groundbased systems can provide hazard detection for all aircraft in airport terminal regions while airborne systems will be needed to provide equipped aircraft with flight path coverage between terminal regions.

  3. Unmanned Aircraft Hazards and their Implications for Regulation

    NASA Technical Reports Server (NTRS)

    Hayhurst, Kelly J.; Maddalon, Jeffrey M.; Miner, Paul S.; DeWalt, Michael P.; McCormick, G. Frank

    2006-01-01

    Use of unmanned aircraft systems (UASs) has been characterized as the next great step forward in the evolution of civil aviation. Indeed, UASs are in limited civil use in the United States today, and many believe that the time is rapidly approaching when they will move into the commercial marketplace, too. To make this a reality, a number of challenges must be overcome to develop the necessary regulatory framework for assuring safe operation of this special class of aircraft. This paper discusses some of what must be done to establish that framework. In particular, we examine hazards specific to the design, operation, and flight crew of UASs, and discuss implications of these hazards for existing policy and guidance. Understanding unique characteristics of UASs that pose new hazards is essential to developing a cogent argument, and the corresponding regulatory framework, for safely integrating these aircraft into civil airspace.

  4. Application of surface electrical discharges to the study of lightning strikes on aircraft

    NASA Technical Reports Server (NTRS)

    Boulay, J. L.; Larigaldie, S.

    1991-01-01

    Considered here is the characterization of surface discharges which provide a facility complementary to that of artificially triggered lightning. General characteristics of a simplified surface discharge, including current waveforms and the constitution of a surface discharge are outlined, and the application of this approach to the study of aircraft lightning strikes is considered. Representations of leader-streamer and return-stroke phases are discussed, and the application to the two-dimensional discharge phase is covered. It is noted that the fact that the initiation times of surface discharges could be controlled, and the path followed by the discharge channels could be predetermined, indicates that it is possible to produce a highly dedicated high performance instrumentation system.

  5. 14 CFR Appendix B to Part 417 - Flight Hazard Area Analysis for Aircraft and Ship Protection

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 14 Aeronautics and Space 4 2011-01-01 2011-01-01 false Flight Hazard Area Analysis for Aircraft... Appendix B to Part 417—Flight Hazard Area Analysis for Aircraft and Ship Protection B417.1Scope This... launch site hazard area analysis that protects the public, aircraft, and ships from the...

  6. 14 CFR Appendix B to Part 417 - Flight Hazard Area Analysis for Aircraft and Ship Protection

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 14 Aeronautics and Space 4 2010-01-01 2010-01-01 false Flight Hazard Area Analysis for Aircraft... Appendix B to Part 417—Flight Hazard Area Analysis for Aircraft and Ship Protection B417.1Scope This... launch site hazard area analysis that protects the public, aircraft, and ships from the...

  7. Hazardous Levels of Commercial Aircraft Response to Atmospheric Turbulence

    NASA Astrophysics Data System (ADS)

    Chang, Ray C.; Ye, Cun-En; Lan, C. Edward; Guan, Wen-Lin

    Jet commercial aircraft in flight are frequently subject to atmospheric turbulence resulting in rapidly varying aerodynamic and flight dynamic characteristics. These varying characteristics not only pose threats to flight safety, but also may cause structural damages and reduce fatigue life. The sudden plunging motion in severe turbulence is the major reason to cause the flight injuries. To express the turbulence intensities as the hazardous levels, the root-mean-square g-load, usually for structural load, has been examined in the past twenty years. The present study is to examine alternative ideas to express the hazardous levels of sudden plunging motion in atmospheric turbulence. The flying-quality parameters of the plunging mode and integrated turbulence-induced downwash will be proposed as more reliable parameters for the turbulence hazard levels.

  8. Hazards of falling debris to people, aircraft, and watercraft

    SciTech Connect

    Cole, J.K.; Young, L.W.; Jordan-Culler, T.

    1997-04-01

    This report is a collection of studies performed at Sandia National Laboratories in support of Phase One (inert debris) for the Risk and Lethality Commonality Team. This team was created by the Range Safety Group of the Range Commander`s Council to evaluate the safety issues for debris generated during flight tests and to develop debris safety criteria that can be adopted by the national ranges. Physiological data on the effects of debris impacts on people are presented. Log-normal curves are developed to relate the impact kinetic energy of fragments to the probability of fatality for people exposed in standing, sitting, or prone positions. Debris hazards to aircraft resulting from engine ingestion or penetration of a structure or windshield are discussed. The smallest mass fragments of aluminum, steel, and tungsten that may be hazardous to current aircraft are defined. Fragment penetration of the deck of a small ship or a pleasure craft is also considered. The smallest mass fragments of aluminum, steel, or tungsten that can penetrate decks are calculated.

  9. A preliminary design proposal for a maritime patrol strike aircraft: MPS-2000 Condor

    NASA Technical Reports Server (NTRS)

    1994-01-01

    The four member graduate design team assembled to submit a proposal for the 1993/1994 RFP at the University of Kansas has designed a four seat, variable swept wing, twin turbofan aircraft with STOL capabilities. The aircraft is named the MPS-2000 Condor and is capable of carrying air-to-surface or air-to-air weapon systems along with attack and surveillance radar and IRF systems. The aircraft has a cruise range of 800 nautical miles, a loiter of 4 hours, and a dash speed of 500 kts.

  10. Linear and nonlinear interpretation of the direct strike lightning response of the NASA F106B thunderstorm research aircraft

    NASA Technical Reports Server (NTRS)

    Rudolph, T. H.; Perala, R. A.

    1983-01-01

    The objective of the work reported here is to develop a methodology by which electromagnetic measurements of inflight lightning strike data can be understood and extended to other aircraft. A linear and time invariant approach based on a combination of Fourier transform and three dimensional finite difference techniques is demonstrated. This approach can obtain the lightning channel current in the absence of the aircraft for given channel characteristic impedance and resistive loading. The model is applied to several measurements from the NASA F106B lightning research program. A non-linear three dimensional finite difference code has also been developed to study the response of the F106B to a lightning leader attachment. This model includes three species air chemistry and fluid continuity equations and can incorporate an experimentally based streamer formulation. Calculated responses are presented for various attachment locations and leader parameters. The results are compared qualitatively with measured inflight data.

  11. Carbon Nanostructures for Electromagnetic Shielding and Lightning Strike Protection Applications in Aircraft

    NASA Astrophysics Data System (ADS)

    Shah, T.; Jones, M.; Alberding, M.; Laszewski, M.

    2012-05-01

    Applied NanoStructured Solutions, LLC (ANS) has developed a unique Chemical Vapor Deposition (CVD) process for the growth of Carbon Nanotubes (CNT) onto various fiber substrates including carbon, glass, ceramics and aramids. This process is continuous and operates at atmospheric pressures enabling high volume/low cost manufacturing. This process infuses conductive CNTs in a highly entangled form referred to as Carbon Nanostructures (CNS) onto the surface of the normally insulative fiber making it highly conductive overall. Composites made from this CNS-infused filler then have unique Electromagnetic Interference (EMI) shielding and Lightening Strike Protection (LSP) properties.

  12. An assessment of the crash fire hazard of liquid hydrogen fueled aircraft

    NASA Technical Reports Server (NTRS)

    1982-01-01

    The crash fire hazards of liquid hydrogen fueled aircraft relative to those of mission equivalent aircraft fueled either with conventional fuel or with liquefied methane were evaluated. The aircraft evaluated were based on Lockheed Corporation design for 400 passenger, Mach 0.85, 5500 n. mile aircraft. Four crash scenarios were considered ranging from a minor incident causing some loss of fuel system integrity to a catastrophic crash. Major tasks included a review of hazardous properties of the alternate fuels and of historic crash fire data; a comparative hazard evluation for each of the three fuels under four crash scenarios a comprehensive review and analysis and an identification of areas further development work. The conclusion was that the crash fire hazards are not significantly different when compared in general for the three fuels, although some fuels showed minor advantages in one respect or another.

  13. Distribution and density of bird species hazardous to aircraft

    USGS Publications Warehouse

    Robbins, C.S.

    1975-01-01

    Only in the past 5 years has it become feasible to map the relative abundance of North American birds. Two programs presently under way and a third that is in the experimental phase are making possible the up-to-date mapping of abundance as well as distribution. A fourth program that has been used successfully in Europe and on a small scale in parts of North America yields detailed information on breeding distribution. The Breeding Bird Survey, sponsored by the U.S. Bureau of Sport Fisheries and Wildlife and the Canadian Wildlife Service, involves 2,000 randomly distributed roadside counts that are conducted during the height of the breeding season in all U.S. States and Canadian Provinces. Observations of approximately 1.4 million birds per year are entered on magnetic tape and subsequently used both for statistical analysis of population trends and for computer mapping of distribution and abundance. The National Audubon Society's Christmas Bird Count is conducted in about 1,000 circles, each 15 miles (24 km) in diameter, in the latter half of December. Raw data for past years have been published in voluminous reports, but not in a form for ready analysis. Under a contract between the U.S. Air Force and the U. S. Bureau of Sport Fisheries and Wildlife (in cooperation with the National Audubon Society), preliminary maps showing distribution and abundance of selected species that are potential hazards to aircraft are presently being mapped and prepared for publication. The Winter Bird Survey, which is in its fifth season of experimental study in a limited area in Central Maryland, may ultimately replace the Christmas Bird Count source. This Survey consists of a standardized 8-kilometer (5-mile) route covered uniformly once a year during midwinter. Bird Atlas programs, which map distribution but not abundance, are well established in Europe and are gaining interest in America

  14. General Models for Assessing Hazards Aircraft Pose to Surface Facilities

    SciTech Connect

    G.E. Ragan

    2002-11-18

    This paper derives formulas for estimating the frequency of accidental aircraft crashes into surface facilities. Objects unintentionally dropped from aircraft are also considered. The approach allows the facility to be well within the flight area; inside the flight area, but close to the edge; or completely outside the flight area.

  15. Thunderstorm hazards flight research: Storm hazards 1980 overview

    NASA Technical Reports Server (NTRS)

    Deal, P. L.; Keyser, G. L.; Fisher, B. D.; Crabill, N. L.

    1981-01-01

    A highly instrumented NASA F-106B aircraft, modified for the storm hazards mission and protected against direct lightning strikes, was used in conjunction with various ground based radar and lightning measurement systems to collect data during thunderstorm penetration flights. During 69 thunderstorm penetrations, there were 10 direct lightning strikes to the aircraft. No problems were encountered with any of the aircraft's systems as a result of the strikes and the research instrumentation performed as designed. Electromagnetic characteristics of nine strikes were recorded, and the results of other experiments confirm the theory that X-ray radiation and nitrous oxide gas are being produced by processes associated directly with thunderstorm electric fields and lightning discharges. A better understanding of aircraft lightning attachment mechanisms and strike zones is being accomplished by careful inspection, identification, and documentation of lightning attachment points and swept stroke paths following each strike to the aircraft.

  16. The relationship of an integral wind shear hazard to aircraft performance limitations

    NASA Technical Reports Server (NTRS)

    Lewis, M. S.; Robinson, P. A.; Hinton, D. A.; Bowles, R. L.

    1994-01-01

    The development and certification of airborne forward-looking wind shear detection systems has required a hazard definition stated in terms of sensor observable wind field characteristics. This paper outlines the definition of the F-factor wind shear hazard index and an average F-factor quantity, calculated over a specified averaging interval, which may be used to judge an aircraft's potential performance loss due to a given wind shear field. A technique for estimating airplane energy changes during a wind shear encounter is presented and used to determine the wind shear intensity, as a function of the averaging interval, that presents significant hazard to transport category airplanes. The wind shear hazard levels are compared to averaged F-factor values at various averaging intervals for four actual wind shear encounters. Results indicate that averaging intervals of about one kilometer could be used in a simple method to discern hazardous shears.

  17. Evaluation of aircraft crash hazard at Los Alamos National Laboratory facilities

    SciTech Connect

    Selvage, R.D.

    1996-07-01

    This report selects a method for use in calculating the frequency of an aircraft crash occurring at selected facilities at the Los Alamos National Laboratory (the Laboratory). The Solomon method was chosen to determine these probabilities. Each variable in the Solomon method is defined and a value for each variable is selected for fourteen facilities at the Laboratory. These values and calculated probabilities are to be used in all safety analysis reports and hazards analyses for the facilities addressed in this report. This report also gives detailed directions to perform aircraft-crash frequency calculations for other facilities. This will ensure that future aircraft-crash frequency calculations are consistent with calculations in this report.

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

    NASA Technical Reports Server (NTRS)

    Kelly, Michael J.

    2013-01-01

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

  19. High performance dash-on-warning air mobile missile system. [first strike avoidance for retaliatory aircraft-borne ICBM counterattack

    NASA Technical Reports Server (NTRS)

    Hague, D. S.; Levin, A. D.

    1978-01-01

    Because fixed missile bases have become increasingly vulnerable to strategic nuclear attack, an air-mobile missile system is proposed, whereby ICBMs can be launched from the hold of large subsonic aircraft following a missile-assisted supersonic dash of the aircraft to a safe distance from their base (about 50 n mi). Three major categories of vehicle design are presented: staged, which employs vertical take-off and a single solid rocket booster similar to that used on the Space Shuttle; unstaged, which employs vertical take-off and four internally-carried reusable liquid rocket engines; and alternative concepts, some using horizontal take-off with duct-burning afterburners. Attention is given to the economics of maintaining 200 ICBMs airborne during an alert (about $600 million for each fleet alert, exclusive of acquisition costs). The chief advantages of the system lie in its reduced vulnerability to suprise attack, because it can be launched on warning, and in the possibility for recall of the aircraft if the warning proves to be a false alarm.

  20. The 1982 direct strike lightning data

    NASA Technical Reports Server (NTRS)

    Thomas, M. E.; Pitts, F. L.

    1983-01-01

    Wideband waveforms data which were obtained during the 1982 direct-strike lightning tests utilizing the NASA F106-B aircraft specially instrumented for lightning electromagnetic measurements. The aircraft was operated in a thunderstorm environment to elicit strikes to the aircraft during this testing period. Electromagnetic field data were recorded to both attached lightning and free field excitation of the aircraft.

  1. Assessment of crash fire hazard of LH sub 2 fueled aircraft

    NASA Technical Reports Server (NTRS)

    Brewer, G. D.; Wittlin, G.; Versaw, E. F.; Parmley, R.; Cima, R.; Walther, E. G.

    1981-01-01

    The relative safety of passengers in LH2 - fueled aircraft, as well as the safety of people in areas surrounding a crash scene, has been evaluated in an analytical study. Four representative circumstances were postulated involving a transport aircraft in which varying degrees of severity of damage were sustained. Potential hazard to the passengers and to the surroundings posed by the spilled fuel was evaluated for each circumstance. Corresponding aircraft fueled with liquid methane, Jet A, and JP-4 were also studied in order to make comparisons of the relative safety. The four scenarios which were used to provide a basis for the evaluation included: (1) a small fuel leak internal to the aircraft, (2) a survivable crash in which a significant quantity of fuel is spilled in a radial pattern as a result of impact with a stationary object while taxiing at fairly low speed, (3) a survivable crash in which a significant quantity of fuel is spilled in an axial pattern as a result of impact during landing, and (4) a non-survivable crash in which a massive fuel spill occurs instantaneously.

  2. A performance improvement case study in aircraft maintenance and its implications for hazard identification.

    PubMed

    Ward, Marie; McDonald, Nick; Morrison, Rabea; Gaynor, Des; Nugent, Tony

    2010-02-01

    Aircraft maintenance is a highly regulated, safety critical, complex and competitive industry. There is a need to develop innovative solutions to address process efficiency without compromising safety and quality. This paper presents the case that in order to improve a highly complex system such as aircraft maintenance, it is necessary to develop a comprehensive and ecologically valid model of the operational system, which represents not just what is meant to happen, but what normally happens. This model then provides the backdrop against which to change or improve the system. A performance report, the Blocker Report, specific to aircraft maintenance and related to the model was developed gathering data on anything that 'blocks' task or check performance. A Blocker Resolution Process was designed to resolve blockers and improve the current check system. Significant results were obtained for the company in the first trial and implications for safety management systems and hazard identification are discussed. Statement of Relevance: Aircraft maintenance is a safety critical, complex, competitive industry with a need to develop innovative solutions to address process and safety efficiency. This research addresses this through the development of a comprehensive and ecologically valid model of the system linked with a performance reporting and resolution system. PMID:20099178

  3. The development of a system for the evaluation of electromagnetic interference with pacemaker function: hazards in the aircraft environment.

    PubMed

    McDeller, A G; Toff, W D; Hobbs, R A; Robb, D J; Camm, A J

    1989-01-01

    It has been recognized for many years that the electromagnetic (EM) environment within aircraft presents a potential hazard to the subject with a pacemaker. Most of the information currently available is, however, several years old and may not be strictly relevant to modern pacemakers and the electromagnetic environment found in today's civil aircraft. In mid 1986 it was therefore decided to investigate the effect on a number of currently available unipolar pacemakers of typical levels of electromagnetic interference encountered in civil aircraft. PMID:2746623

  4. Neotectonics, geodesy, and seismic hazard in the Northern Walker Lane of Western North America: Thirty kilometers of crustal shear and no strike-slip?

    NASA Astrophysics Data System (ADS)

    Wesnousky, Steven G.; Bormann, Jayne M.; Kreemer, Corné; Hammond, William C.; Brune, James N.

    2012-05-01

    Roughly 30 km of cumulative right-lateral crustal displacement and 5-6 mm/yr of the ongoing relative right-lateral motion between the Pacific and North American plates are observed in the northern Walker Lane. The right-lateral shear has been accommodated in large part by the development of a set of discontinuous, en echelon, normal fault-bounded basins and perhaps significant vertical axis rotations of the intervening crust. The observations provide an illustrative example of how large amounts of crustal shear may be accommodated in the absence of strike-slip faults and point to difficulties attendant to melding geologic and geodetic observations in the analysis of seismic hazard. In this particular case, the assumption that all geodetically observed shear across the area will be recorded by earthquake displacements may be flawed.

  5. Insight of the fusion behavior of volcanic ash: Implications for Volcanic ash Hazards to Aircraft Safety

    NASA Astrophysics Data System (ADS)

    Song, Wenjia; Hess, Kai-Uwe; Küppers, Ulrich; Scheu, Bettina; Cimarelli, Corrado; Lavallée, Yan; Sohyun, Park; Gattermann, Ulf; Müller, Dirk; Dingwell, Donald Bruce

    2014-05-01

    The interaction of volcanic ash with jet turbines during via ingestion of ash into engines operating at supra-volcanic temperatures is widely recognized as a potentially fatal hazard for jet aircraft. In the past 12 years, more than 60 modern jet airplanes, mostly jumbo jets, have been damaged by drifting clouds of volcanic ash that have contaminated air routes and airport facilities. Seven of these encounters are known to have caused in flight loss of engine power to jumbo jets carrying a total of more than 2000 passengers. The fusibility of volcanic ash is believed to impact strongly its deposition in the hotter parts of jet engines. Despite this, explicit investigation of ash sintering using standardized techniques is in its infancy. Volcanic ash may vary widely in its physical state and chemical composition between and even within explosive volcanic eruptions. Thus a comparative study of the fusibility of ash which involves a standard recognized techniques would be highly desirable. In this work, nine samples of fine ash, deposited from co-pyroclastic offrom nine different volcanoes which cover a broad range of chemical composition, were investigated. Eight of them were collected from 2001-2009 eruptions. Because of the currently elevated level of eruptive activity and its potential hazards to aircraft safety and the remaining one sample was collected from a 12,121 ± 114 yr B.P. eruption. We used the method of accessing the behavior of deposit-forming impurities in high temperature boiler plants on the basis of observations of the change in shape and size of a cylindrical coal ash to study the fusion phenomena as well as determine the volcanic ash melting behavior by defining four characteristic temperatures (shrinkage temperature, deformation temperature, hemispherical temperature, and flow temperature) by means of heating microscope instrument and different thermal analysis methods. Here, we find that there are similar sticking ability and flow behavior of

  6. Aircraft

    DOEpatents

    Hibbs, B.D.; Lissaman, P.B.S.; Morgan, W.R.; Radkey, R.L.

    1998-09-22

    This disclosure provides a solar rechargeable aircraft that is inexpensive to produce, is steerable, and can remain airborne almost indefinitely. The preferred aircraft is a span-loaded flying wing, having no fuselage or rudder. Travelling at relatively slow speeds, and having a two-hundred foot wingspan that mounts photovoltaic cells on most all of the wing`s top surface, the aircraft uses only differential thrust of its eight propellers to turn. Each of five sections of the wing has one or more engines and photovoltaic arrays, and produces its own lift independent of the other sections, to avoid loading them. Five two-sided photovoltaic arrays, in all, are mounted on the wing, and receive photovoltaic energy both incident on top of the wing, and which is incident also from below, through a bottom, transparent surface. The aircraft is capable of a top speed of about ninety miles per hour, which enables the aircraft to attain and can continuously maintain altitudes of up to sixty-five thousand feet. Regenerative fuel cells in the wing store excess electricity for use at night, such that the aircraft can sustain its elevation indefinitely. A main spar of the wing doubles as a pressure vessel that houses hydrogen and oxygen gases for use in the regenerative fuel cell. The aircraft has a wide variety of applications, which include weather monitoring and atmospheric testing, communications, surveillance, and other applications as well. 31 figs.

  7. Aircraft

    DOEpatents

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

    1998-01-01

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

  8. Physician strikes.

    PubMed

    Thompson, Stephen L; Salmon, J Warren

    2014-11-01

    Throughout medical history, physicians have rarely formed unions and/or carried out strikes. In a profession faced with the turmoil of health reform and increasing pressure to change their practices and lifestyles, will physicians resort to unionization for collective bargaining, and will a strike weapon be used to fight back against the array of corporate and government powers involved in the transformation of the American health-care system? This article examines the question of whether there could be such a thing as an ethical physician strike. Although physicians have not historically used collective bargaining or the strike weapon, the rapidly changing practice environment in the United States might push physicians and other health-care professionals toward unionization. This article considers the ethical questions that would arise if physicians started taking advantage of labor laws, and it lays out criteria for an ethical strike. PMID:25367473

  9. Lightning strikes to a NASA airplane penetrating thunderstorms at low altitudes

    NASA Technical Reports Server (NTRS)

    Mazur, V.; Fisher, B. D.; Gerlach, J. C.

    1986-01-01

    The NASA Storm Hazards program was dedicated during the 1984 storm season to a study of lightning strikes on an instrumented F-106B aircraft, during penetrations of thunderstorms at altitudes lower than the 6-8 km center of lightning flash density. These altitudes coincide with the negative charge region of thunderstorms. An analysis of the correlation between the UHF band radar data obtained and TV images of lightning strikes indicates that, with a known aircraft position relative to the radar, the lightning channel motion can be adequately interpreted on the basis of radar echo evolution.

  10. Pulsed coherent fiber lidar transceiver for aircraft in-flight turbulence and wake-vortex hazard detection

    NASA Astrophysics Data System (ADS)

    Akbulut, M.; Hwang, J.; Kimpel, F.; Gupta, S.; Verdun, H.

    2011-06-01

    We report on the development of a fiber-optic pulsed coherent lidar transceiver for wind-velocity and aircraft wake-vortex hazard detection. The all-fiber 1.5μm transmitter provides up to 560 μJ energy at 25 kHz with 800 ns pulse width (pump limited). Performance simulations indicate wake-vortex hazard signature detection up to ~2.5km range with a receiver sensitivity of ~2 fW (SNR=6), suited for an aircraft landing scenario. Furthermore, the transceiver is implemented using high-speed FPGA based control and digital-signal-processing, enabling its use as a flexible pulse-format multi-function in-flight lidar sensor. We present the latest laboratory results and preliminary testing of this pulsed coherent lidar transceiver, along with the lidar performance simulation of wake-vortex eddy models.

  11. AIRCRAFT DEPAINTING TECHNOLOGY

    EPA Science Inventory

    Chemical paint strippers historically used for aircraft contained toxic and hazardous components; aircraft depainting operations are a major source of hazardous waste generation in DOD. Federal and state agencies have begun to restrict using these hazardous materials and Governme...

  12. Striking Clepsydras

    NASA Astrophysics Data System (ADS)

    Nam, Moon-Hyon

    The term "Striking Clepsydra" is a shortened translation of the Korean name Jagyeongnu (自擊漏, tzu-chi lou in Chinese, literally "automatic-striking water-clock"). It was given to the two monumental time-keeping installations built by chief court engineer Yeong-sil Jang in AD 1432-38 under King Sejong (r. AD 1418-50) of the Joseon dynasty (1392-1910) in Seoul. These were housed separately in the Gyeongbok palace complex as major installations of the Royal Observatory Ganuidae equipped during 1432-38. One was the Striking Palace Clepsydra Borugangnu that was employed as the standard time-keeper from 1434, and the other was the Striking Heavenly Clepsydra Heumgyeonggangnu that was put into use not only as the symbol of Neo-Confucian ideology from 1438, but also as a demonstrational orrery and time-keeper. These were restored several times through the dynasty after loss by fires and warfare, and clepsydra-making technologies were succeeded by the development of armillary clocks in 1669. The National Palace Museum of Korea recreated the 1434 Striking Palace Clepsydra of King Sejong, and the replica was installed for permanent exhibition from November 2007.

  13. Striking responsibilities.

    PubMed

    Brecher, R

    1985-06-01

    It is commonly held that National Health Service (NHS) workers are under a moral obligation not to go on strike, because doing so might well result in people's dying. Unless sainthood is demanded, however, this position is untenable: indeed, those most vociferously pursuing it are often those who bear the greatest responsibility, on their own grounds, for needless death and suffering. PMID:4009635

  14. Overview of the preparation and use of an OV-10 aircraft for wake vortex hazards flight experiments

    NASA Technical Reports Server (NTRS)

    Stuever, Robert A.; Stewart, Eric C.; Rivers, Robert A.

    1995-01-01

    An overview is presented of the development, use, and current flight-test status of a highly instrumented North American Rockwell OV-10A Bronco as a wake-vortex-hazards research aircraft. A description of the operational requirements and measurements criteria, the resulting instrumentation systems and aircraft modifications, system-calibration and research flights completed to date, and current flight status are included. These experiments are being conducted by the National Aeronautics and Space Administration as part of an effort to provide the technology to safely improve the capacity of the nation's air transportation system and specifically to provide key data in understanding and predicting wake vortex decay, transport characteristics, and the dynamics of encountering wake turbulence. The OV-10A performs several roles including meteorological measurements platform, wake-decay quantifier, and trajectory-quantifier for wake encounters. Extensive research instrumentation systems include multiple airdata sensors, video cameras with cockpit displays, aircraft state and control-position measurements, inertial aircraft-position measurements, meteorological measurements, and an on-board personal computer for real-time processing and cockpit display of research data. To date, several of the preliminary system check flights and two meteorological-measurements deployments have been completed. Several wake encounter and wake-decay-measurements flights are planned for the fall of 1995.

  15. Bibliography on aircraft fire hazards and safety. Volume 1: Hazards. Part 1: Key numbers 1 to 817

    NASA Technical Reports Server (NTRS)

    Pelouch, J. J., Jr. (Compiler); Hacker, P. T. (Compiler)

    1974-01-01

    Ignition temperatures of n-hexane, n-octane, n-decane, JP-6 jet fuel, and aircraft engine oil MIL-7-7808 (0-60-18) were determined in air using heated Pyrex cylinders and Nichrome wires, rods, or tubes. Ignition temperature varied little with fuel-air ratio, but increased as the size of the heat source was decreased. Expressions are given which define the variation of the hot surface ignition temperatures of these combustibles with the radius and the surface area of the heat source. The expressions are applicable to stagnant or low velocity flow conditions (less than 0.2 in./sec.). In addition, the hot gas ignition temperatures of the combustible vapor-air mixtures were determined with jets of hot air. These ignition temperatures also varied little with fuel-air ratio and increased as the diameter of the heat sources was decreased.

  16. Lightning hazards overview: Aviation requirements and interests

    NASA Technical Reports Server (NTRS)

    Corn, P. B.

    1979-01-01

    A ten-year history of USAF lightning incidents is presented along with a discussion of the problems posed by lightning to current aircraft, and the hazards it constitutes to the electrical and electronic subsystems of new technology aircraft. Lightning technical protection technical needs, both engineering and operational, include: (1) in-flight data on lightning electrical parameters; (2) tech base and guidelines for protection of advanced systems and structures; (3) improved laboratory test techniques; (4) analysis techniques for predicting induced effects; (5) lightning strike incident data from general aviation; (6) lightning detection systems; (7) pilot reports on lightning strikes; and (8) better training in lightning awareness.

  17. Influence of fault trend, fault bends, and fault convergence on shallow structure, geomorphology, and hazards, Hosgri strike-slip fault, offshore central California

    NASA Astrophysics Data System (ADS)

    Johnson, S. Y.; Watt, J. T.; Hartwell, S. R.

    2012-12-01

    dies out northward where we propose that its slip transfers to active structures in the Piedras Blancas fold belt. Given the continuity of the Hosgri Fault Zone through our study area, earthquake hazard assessments should incorporate a minimum rupture length of 110 km. Our data do not constrain lateral slip rates on the Hosgri, which probably vary along the fault (both to the north and south) as different structures converge and diverge but are likely in the geodetically estimated range of 2 to 4 mm/yr. More focused mapping of lowstand geomorphic features (e.g., channels, paleoshorelines) has the potential to provide better constraints. The post-Last-Glacial Maximum unconformity is an important surface for constraining vertical deformation, yielding local fault offset rates that may be as high as 1.4 mm/yr and off-fault deformation rates as high as 0.5 mm/yr. These vertical rates are short-term and not sustainable over longer geologic time, emphasizing the complex evolution and dynamics of strike-slip zones.

  18. Sensing Hazards with Operational Unmanned Technology: NOAA's Application of the Global Hawk Aircraft for High Impact Weather Forecasting

    NASA Astrophysics Data System (ADS)

    Coffey, J. J.; Wick, G. A.; Hood, R. E.; Dunion, J. P.; Black, M. L.; Kenul, P.

    2015-12-01

    The NOAA Unmanned Aircraft Systems (UAS) program has begun the project Sensing Hazards with Operational Unmanned Technology (SHOUT) to evaluate the potential of high altitude, long endurance unmanned aircraft like the Global Hawk to improve forecasts of high-impact weather events and mitigate any degradations in the forecasts that might occur if there were a gap in satellite coverage. The first phase of the project is occurring this August and September using the NASA Global Hawk to study the impact of targeted observations of hurricanes and tropical cyclones. This follows several successful research missions conducted by both NASA and NOAA. Instruments on the aircraft for SHOUT include the Airborne Vertical Atmospheric Profiling System (AVAPS or dropsondes), the High Altitude MMIC Sounding Radiometer (HAMSR, a microwave sounder), the High-Altitude Imaging Wind and Rain Airborne Profiler (HIWRAP, a scanning Doppler precipitation radar), and the Lightning Instrument Package (LIP). The observations are being utilized for real-time forecasting, ingestion into operational weather models, and in post mission impact studies. Data impact is being evaluated through a combination of Observing System Experiments (OSEs) and Observing System Simulation Experiments (OSSEs). This presentation describes observations collected during this year's campaign, utilization of the data at the National Hurricane Center, and the results of preliminary data impact assessments of the data from SHOUT and previous experiments.

  19. 77 FR 22504 - Hazardous Materials; Packages Intended for Transport by Aircraft

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-04-16

    ... Policies and Procedures of the Department of Transportation (44 FR 11034). Additionally, E.O. 13563... transportation of liquid hazardous materials by preventing releases or containing releases that do occur within... that a combination packaging intended for the air transportation of liquid hazardous materials...

  20. 14 CFR 35.38 - Lightning strike.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Lightning strike. 35.38 Section 35.38... STANDARDS: PROPELLERS Tests and Inspections § 35.38 Lightning strike. The applicant must demonstrate, by... lightning strike without causing a major or hazardous propeller effect. The limit to which the propeller...

  1. 14 CFR 35.38 - Lightning strike.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 14 Aeronautics and Space 1 2011-01-01 2011-01-01 false Lightning strike. 35.38 Section 35.38... STANDARDS: PROPELLERS Tests and Inspections § 35.38 Lightning strike. The applicant must demonstrate, by... lightning strike without causing a major or hazardous propeller effect. The limit to which the propeller...

  2. 14 CFR 35.38 - Lightning strike.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 14 Aeronautics and Space 1 2012-01-01 2012-01-01 false Lightning strike. 35.38 Section 35.38... STANDARDS: PROPELLERS Tests and Inspections § 35.38 Lightning strike. The applicant must demonstrate, by... lightning strike without causing a major or hazardous propeller effect. The limit to which the propeller...

  3. 14 CFR 35.38 - Lightning strike.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 14 Aeronautics and Space 1 2013-01-01 2013-01-01 false Lightning strike. 35.38 Section 35.38... STANDARDS: PROPELLERS Tests and Inspections § 35.38 Lightning strike. The applicant must demonstrate, by... lightning strike without causing a major or hazardous propeller effect. The limit to which the propeller...

  4. 14 CFR 35.38 - Lightning strike.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 14 Aeronautics and Space 1 2014-01-01 2014-01-01 false Lightning strike. 35.38 Section 35.38... STANDARDS: PROPELLERS Tests and Inspections § 35.38 Lightning strike. The applicant must demonstrate, by... lightning strike without causing a major or hazardous propeller effect. The limit to which the propeller...

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

    NASA Technical Reports Server (NTRS)

    Kelly, Michael J.

    2013-01-01

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

  6. The 1983 direct strike lightning data, part 1

    NASA Technical Reports Server (NTRS)

    Thomas, Mitchel E.

    1985-01-01

    Data waveforms are presented which were obtained during the 1983 direct strike lightning tests utilizing the NASA F106-B aircraft specially instrumented for lightning electromagnetic measurements. The aircraft was operated in the vicinity of the NASA Langley Research Center, Hampton, Virginia, in a thunderstorm environment to elicit strikes. Electromagnetic field data and conduction currents on the aircraft were recorded for attached lightning. Part 1 contains 435 pages of lightning strike data in chart form.

  7. Evaluation of a technique to quantify microburst windshear hazard potential to aircraft

    NASA Technical Reports Server (NTRS)

    Byrd, G. P.; Proctor, F. H.; Bowles, R. L.

    1990-01-01

    A wind shear hazard index, known as the F-factor, is investigated for application with look-ahead sensors. Based on data from microburst simulations with the NASA windshear model, the downdraft results in a significant contribution to the wind shear hazard, especially at altitudes above 150 meters. Since most look-ahead wind shear sensors can only detect horizontal shear and cannot measure vertical velocity, a relationship is developed for approximating the total F-factor using information based solely on the horizontal wind shear and altitude. This relationship is then tested using data from several microburst cases.

  8. Storm hazards '79: F-106B operations summary

    NASA Technical Reports Server (NTRS)

    Fisher, B. D.; Keyser, G. L., Jr.; Deal, P. L.; Thomas, M. E.; Pitts, F. L.

    1980-01-01

    Preliminary flight tests with a F-106B aircraft were made on the periphery of isolated thunder cells using weather radar support. In addition to storm hazards correlation research, a direct-strike lightning measurement experiment and an atmospheric chemistry experiment were conducted. Two flights were made to close proximity to lightning generating cumulonimbus clouds; however, no direct lightning strikes were experienced. Although no discernible lightning transients were recorded, many operational techniques were identified and established.

  9. Wildlife strike risk assessment in several Italian airports: lessons from BRI and a new methodology implementation.

    PubMed

    Soldatini, Cecilia; Albores-Barajas, Yuri Vladimir; Lovato, Tomas; Andreon, Adriano; Torricelli, Patrizia; Montemaggiori, Alessandro; Corsa, Cosimo; Georgalas, Vyron

    2011-01-01

    The presence of wildlife in airport areas poses substantial hazards to aviation. Wildlife aircraft collisions (hereafter wildlife strikes) cause losses in terms of human lives and direct monetary losses for the aviation industry. In recent years, wildlife strikes have increased in parallel with air traffic increase and species habituation to anthropic areas. In this paper, we used an ecological approach to wildlife strike risk assessment to eight Italian international airports. The main achievement is a site-specific analysis that avoids flattening wildlife strike events on a large scale while maintaining comparable airport risk assessments. This second version of the Birdstrike Risk Index (BRI2) is a sensitive tool that provides different time scale results allowing appropriate management planning. The methodology applied has been developed in accordance with the Italian Civil Aviation Authority, which recognizes it as a national standard implemented in the advisory circular ENAC APT-01B. PMID:22194950

  10. Wildlife Strike Risk Assessment in Several Italian Airports: Lessons from BRI and a New Methodology Implementation

    PubMed Central

    Soldatini, Cecilia; Albores-Barajas, Yuri Vladimir; Lovato, Tomas; Andreon, Adriano; Torricelli, Patrizia; Montemaggiori, Alessandro; Corsa, Cosimo; Georgalas, Vyron

    2011-01-01

    The presence of wildlife in airport areas poses substantial hazards to aviation. Wildlife aircraft collisions (hereafter wildlife strikes) cause losses in terms of human lives and direct monetary losses for the aviation industry. In recent years, wildlife strikes have increased in parallel with air traffic increase and species habituation to anthropic areas. In this paper, we used an ecological approach to wildlife strike risk assessment to eight Italian international airports. The main achievement is a site-specific analysis that avoids flattening wildlife strike events on a large scale while maintaining comparable airport risk assessments. This second version of the Birdstrike Risk Index (BRI2) is a sensitive tool that provides different time scale results allowing appropriate management planning. The methodology applied has been developed in accordance with the Italian Civil Aviation Authority, which recognizes it as a national standard implemented in the advisory circular ENAC APT-01B. PMID:22194950

  11. Low speed wind tunnel investigation of span load alteration, forward-located spoilers, and splines as trailing-vortex-hazard alleviation devices on a transport aircraft model

    NASA Technical Reports Server (NTRS)

    Croom, D. R.; Dunham, R. E., Jr.

    1975-01-01

    The effectiveness of a forward-located spoiler, a spline, and span load alteration due to a flap configuration change as trailing-vortex-hazard alleviation methods was investigated. For the transport aircraft model in the normal approach configuration, the results indicate that either a forward-located spoiler or a spline is effective in reducing the trailing-vortex hazard. The results also indicate that large changes in span loading, due to retraction of the outboard flap, may be an effective method of reducing the trailing-vortex hazard.

  12. Bibliography on aircraft fire hazards and safety. Volume 2: Safety. Part 1: Key numbers 1 to 524

    NASA Technical Reports Server (NTRS)

    Pelouch, J. J., Jr. (Compiler); Hacker, P. T. (Compiler)

    1974-01-01

    Bibliographic citations are presented to describe and define aircraft safety methods, equipment, and criteria. Some of the subjects discussed are: (1) fire and explosion suppression using whiffle balls, (2) ultraviolet flame detecting sensors, (3) evaluation of flame arrestor materials for aircraft fuel systems, (4) crash fire prevention system for supersonic commercial aircraft, and (5) fire suppression for aerospace vehicles.

  13. Mitigating hazards to aircraft from drifting volcanic clouds by comparing and combining IR satellite data with forward transport models

    NASA Astrophysics Data System (ADS)

    Matiella Novak, M. Alexandra

    Volcanic ash clouds in the upper atmosphere (>10km) present a significant hazard to the aviation community and in some cases cause near-disastrous situations for aircraft that inadvertently encounter them. The two most commonly used techniques for mitigating hazards to aircraft from drifting volcanic clouds are (1) using data from satellite observations and (2) the forecasting of dispersion and trajectories with numerical models. This dissertation aims to aid in the mitigation of this hazard by using Moderate Infrared Resolution Spectroradiometer (MODIS) and Advanced Very High Resolution Radiometer (AVHRR) infrared (IR) satellite data to quantitatively analyze and constrain the uncertainties in the PUFF volcanic ash transport model. Furthermore, this dissertation has experimented with the viability of combining IR data with the PUFF model to increase the model's reliability. Comparing IR satellite data with forward transport models provides valuable information concerning the uncertainty and sensitivity of the transport models. A study analyzing the viability of combining satellite-based information with the PUFF model was also done. Factors controlling the cloud-shape evolution, such as the horizontal dispersion coefficient, vertical distribution of particles, the height of the cloud, and the location of the cloud were all updated based on observations from satellite data in an attempt to increase the reliability of the simulations. Comparing center of mass locations--calculated from satellite data--to HYSPLIT trajectory simulations provides insight into the vertical distribution of the cloud. A case study of the May 10, 2003 Anatahan Volcano eruption was undertaken to assess methods of calculating errors in PUFF simulations with respect to the transport and dispersion of the erupted cloud. An analysis of the factors controlling the cloud-shape evolution of the cloud in the model was also completed and compared to the shape evolution of the cloud observed in the

  14. The NASA F-106B Storm Hazards Program

    NASA Technical Reports Server (NTRS)

    Neely, W. R., Jr.; Fisher, B. D.

    1983-01-01

    During the NASA LRC Storm Hazards Program, 698 thunderstorm precipitations were made from 1980 to 1983 with an F-106B aircraft in order to record direct lightning strike data and the associated flight conditions. It was found that each of the three composite fin caps tested experienced multiple lightning attachments with only minor cosmetic damage. The maximum current level was only 20 ka, which is well below the design standard of 200 ka; however, indications are that the current rate of rise standard has been approached and may be exceeded in a major strike. The peak lightning strike rate occurred at ambient temperatures between -40 and -45 C, while most previously reported strikes have occurred at or near the freezing level. No significant operational difficulties or major aircraft damage resulting from the thunderstorm penetrations have been found.

  15. Tectonic geomorphology and paleoseismology of strike-slip faults in Jamaica: Implications for distribution of strain and seismic hazard along the southern edge of the Gonave microplate

    NASA Astrophysics Data System (ADS)

    Koehler, R. D.; Mann, P.; Brown, L. A.

    2009-12-01

    The east-west, left lateral strike-slip fault system forming the southern edge of the Gonave microplate crosses the110-km-long and 70-km-wide island of Jamaica. GPS measurements in the northeastern Caribbean are supportive of the microplate interpretation and indicate that ~ half of the Caribbean-North America left-lateral plate motion (8-14 mm/yr) is carried by the Plantain Garden (PGFZ) and associated faults in Jamaica. We performed Neotectonic mapping of the Plantain Garden fault along the southern rangefront of the Blue Mountains and conducted a paleoseismic study of the fault at Morant River. Between Holland Bay and Morant River, the fault is characterized by a steep, faceted, linear mountain front, prominent linear valleys and depressions, shutter ridges, and springs. At the eastern end of the island, the PGFZ is characterized by a left-stepping fault geometry that includes a major, active hot spring. The river cut exposure at Morant River exposes a 1.5-m-wide, sub-vertical fault zone juxtaposing sheared alluvium and faulted Cretaceous basement rocks. This section is overlain by an, unfaulted 3-m-thick fluvial terrace inset into a late Pleistocene terrace that is culturally modified. Upward fault terminations indicate the occurrence of three paleoearthquakes that occurred prior to deposition of the flat lying inset terrace around 341-628 cal yr BP. At this time, our radiocarbon results suggest that we can rule out the PGFZ as the source of the 1907 Kingston earthquake 102 years ago, as well as, the 1692 event that destroyed Port Royal 317 years ago and produced a major landslide at Yallahs. Pending OSL ages will constrain the age of the penultimate and most recent ruptures. Gently to steeply dipping rocks as young as Pliocene exposed in roadcuts within the low coastal hills south of and parallel to the Plantain Garden fault may indicate active folding and blind thrust faulting. These structures are poorly characterized and may accommodate an unknown amount of

  16. The Sudbury School Strike.

    ERIC Educational Resources Information Center

    Wilkinson, Derek

    1989-01-01

    Although the deleterious effects of teacher strikes on students have been proclaimed in the new media, scant research exists. This study detects no effects whatever in subsequent university performance of a cohort whose last year of high school was interrupted by a three-month strike. The strike did influence the non-college-bound student dropout…

  17. Rattlesnake strike behavior: kinematics

    PubMed

    Kardong; v

    1998-03-01

    The predatory behavior of rattlesnakes includes many distinctive preparatory phases leading to an extremely rapid strike, during which venom is injected. The rodent prey is then rapidly released, removing the snake's head from retaliation by the prey. The quick action of the venom makes possible the recovery of the dispatched prey during the ensuing poststrike period. The strike is usually completed in less than 0.5 s, placing a premium on an accurate strike that produces no significant errors in fang placement that could result in poor envenomation and subsequent loss of the prey. To clarify the basis for effective strike performance, we examined the basic kinematics of the rapid strike using high-speed film analysis. We scored numerous strike variables. Four major results were obtained. (1) Neurosensory control of the strike is based primarily upon sensory inputs via the eyes and facial pits to launch the strike, and upon tactile stimuli after contact. Correction for errors in targeting occurs not by a change in strike trajectory, but by fang repositioning after the jaws have made contact with the prey. (2) The rattlesnake strike is based upon great versatility and variation in recruitment of body segments and body postures. (3) Forces generated during acceleration of the head are transferred to posterior body sections to decelerate the head before contact with the prey, thereby reducing impact forces upon the snake's jaws. (4) Body acceleration is based on two patterns of body displacement, one in which acute sections of the body open like a gate, the other in which body segments flow around postural curves similar to movements seen during locomotion. There is one major implication of these results: recruitment of body segments, launch postures and kinematic features of the strike may be quite varied from strike to strike, but the overall predatory success of each strike by a rattlesnake is very consistent.

    PMID:9464964

  18. Lightning Often Strikes Twice

    NASA Technical Reports Server (NTRS)

    2005-01-01

    Contrary to popular misconception, lightning often strikes the same place twice. Certain conditions are just ripe for a bolt of electricity to come zapping down; and a lightning strike is powerful enough to do a lot of damage wherever it hits. NASA created the Accurate Location of Lightning Strikes technology to determine the ground strike point of lightning and prevent electrical damage in the immediate vicinity of the Space Shuttle launch pads at Kennedy Space Center. The area surrounding the launch pads is enmeshed in a network of electrical wires and components, and electronic equipment is highly susceptible to lightning strike damage. The accurate knowledge of the striking point is important so that crews can determine which equipment or system needs to be retested following a strike. Accurate to within a few yards, this technology can locate a lightning strike in the perimeter of the launch pad. As an added bonus, the engineers, then knowing where the lightning struck, can adjust the variables that may be attracting the lightning, to create a zone that will be less susceptible to future strikes.

  19. Radial arm strike rail

    DOEpatents

    McKeown, Mark H.; Beason, Steven C.

    1991-01-01

    The radial arm strike rail assembly is a system for measurement of bearings, directions, and stereophotography for geologic mapping, particularly where magnetic compasses are not appropriate. The radial arm, pivoting around a shaft axis, provides a reference direction determination for geologic mapping and bearing or direction determination. The centerable and levelable pedestal provide a base for the radial arm strike rail and the telescoping camera pedestal. The telescoping feature of the radial arm strike rail allows positioning the end of the rail for strike direction or bearing measurement with a goniometer.

  20. Cloud-to-ground strikes to the NASA F-106 airplane

    NASA Technical Reports Server (NTRS)

    Mazur, Vladislav; Fisher, Bruce D.; Brown, Philip W.

    1988-01-01

    Cloud-to-ground (CG) lightning strike data on the NASA F-106B research aircraft obtained during the 1984-86 storm seasons in the vicinity of Wallops Island, Virginia, are analyzed. The results suggest that CG strikes may represent a significant portion of the total number of lightning strikes encountered by the aircraft at altitudes below 6 km. It is unlikely that an aircraft encounters the first return stroke of the CG flash. The current values of the CG strikes are not different from currents in other types of strikes.

  1. Lightning effects on aircraft

    NASA Technical Reports Server (NTRS)

    1977-01-01

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

  2. The 1984 direct strike lightning data, part 1

    NASA Technical Reports Server (NTRS)

    Thomas, Mitchel E.; Carney, Harold K.

    1986-01-01

    Data waveforms are presented which were obtained during the 1984 direct-strike lightning tests utilizing the NASA F106-B aircraft specially instrumented for lightning electromagnetic measurements. The aircraft was operated in the vicinity of the NASA Langley Research Center, Hampton, Virginia, in a thunderstorm environment to elicit strikes. Electromagnetic field data and conduction currents on the aircraft were recorded for attached lightning. The entire transient recorder data obtained for 247 uses and 11 nearby flashes in the 1984 campaign are presented. This is part 1, consisting of summary and conclusion.

  3. Strike Manual: Related to Potential School Employee Strike Action.

    ERIC Educational Resources Information Center

    Paterson, Lee T., Ed.

    This manual is designed to help school boards and administrators avoid strikes, survive them, and recover from them when they are over. Chapter 1 distinguishes between public and private sector strikes; defines different kinds of strike strategies, negotiation goals, and strike goals; and provides a strike evaluation checklist for the employee…

  4. A bird strike handbook for base-level managers

    NASA Astrophysics Data System (ADS)

    Payson, R. P.; Vance, J. D.

    1984-09-01

    To help develop more awareness about bird strikes and bird strike reduction techniques, this thesis compiled all relevant information through an extensive literature search, review of base-level documents, and personal interviews. The final product--A Bird Strike Handbook for Base-Level Managers--provides information on bird strike statistics, methods to reduce the strike hazards, and means to obtain additional assistance. The handbook is organized for use by six major base agencies: Maintenance, Civil Engineering, Operations, Air Field Management, Safety, and Air Traffic Control. An appendix follows at the end.

  5. 40 CFR 87.6 - Aircraft safety.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 20 2014-07-01 2013-07-01 true Aircraft safety. 87.6 Section 87.6... POLLUTION FROM AIRCRAFT AND AIRCRAFT ENGINES General Provisions § 87.6 Aircraft safety. The provisions of... be met within the specified time without creating a hazard to aircraft safety....

  6. 40 CFR 87.6 - Aircraft safety.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 21 2013-07-01 2013-07-01 false Aircraft safety. 87.6 Section 87.6... POLLUTION FROM AIRCRAFT AND AIRCRAFT ENGINES General Provisions § 87.6 Aircraft safety. The provisions of... be met within the specified time without creating a hazard to aircraft safety....

  7. Should doctors strike?

    PubMed

    Park, John J; Murray, Scott A

    2014-05-01

    Last year in June, British doctors went on strike for the first time since 1975. Amidst a global economic downturn and with many health systems struggling with reduced finances, around the world the issue of public health workers going on strike is a very real one. Almost all doctors will agree that we should always follow the law, but often the law is unclear or does not cover a particular case. Here we must appeal to ethical discussion. The General Medical Council, in its key guidance document for practising doctors, Good Medical Practice, claims that 'Good doctors make the care of their patients their first concern'. Is this true? And if so, how is this relevant to the issue of striking? One year on since the events, we carefully reflect and argue whether it was right for doctors to pursue strike action, and call for greater discussion of ethical issues such as the recent strikes, particularly among younger members of the profession. PMID:23788560

  8. Raptors and aircraft

    USGS Publications Warehouse

    Smith, D.G.; Ellis, D.H.; Johnson, T.H.

    1988-01-01

    Less than 5% of all bird strikes of aircraft are by raptor species, but damage to airframe structure or jet engine dysfunction are likely consequences. Beneficial aircraft-raptor interactions include the use of raptor species to frighten unwanted birds from airport areas and the use of aircraft to census raptor species. Many interactions, however, modify the raptor?s immediate behavior and some may decrease reproduction of sensitive species. Raptors may respond to aircraft stimuli by exhibiting alarm, increased heart rate, flushing or fleeing and occasionally by directly attacking intruding aircraft. To date, most studies reveal that raptor responses to aircraft are brief and do not limit reproduction; however, additional study is needed.

  9. A decade of U.S. Air Force bat strikes

    USGS Publications Warehouse

    Peurach, Suzanne C.; Dove, Carla J.; Stepko, Laura

    2009-01-01

    From 1997 through 2007, 821 bat strikes were reported to the U.S. Air Force (USAF) Safety Center by aircraft personnel or ground crew and sent to the National Museum of Natural History, Smithsonian Institution, for identification. Many samples were identified by macroscopic and or microscopic comparisons with bat specimens housed in the museum and augmented during the last 2 years by DNA analysis. Bat remains from USAF strikes during this period were received at the museum from 40 states in the United States and from 20 countries. We confirmed that 46% of the strikes were caused by bats, but we did not identify them further; we identified 5% only to the family or genus level, and 49% to the species level. Fifty-five of the 101 bat-strike samples submitted for DNA analysis have been identified to the species level. Twenty-five bat species have been recorded striking USAF planes worldwide. The Brazilian free-tailed bat (Tadarida brasiliensis; n = 173) is the species most commonly identified in USAF strike impacts, followed by the red bat (Lasiurus borealis; n = 83). Bat strikes peak during the spring and fall, with >57% occurring from August through October; 82% of the reports that included time of strike were recorded between 2100 and 0900 hours. More than 12% of the bat strikes were reported at >300 m above ground level (AGL). Although <1% of the bat-strike reports indicated damage to USAF aircraft, cumulative damage for 1997 through 2007 totaled >$825,000 and >50% of this sum was attributable to 5 bat-strike incidents. Only 5 bats from the 10 most damaging bat strikes were identified to the species level, either because we did not receive remains with the reports or the sample was insufficient for identification.

  10. Hunger strike for science

    NASA Astrophysics Data System (ADS)

    Carlowicz, Michael

    Lamenting the degenerating working conditions for scientists in Russia, geophysicist Vladimir Strakhov and physicist Igor Naumenko-Bondarenko of the United Institute of Physics of the Earth (UIPE) at the Russian Academy of Sciences (RAS) have begun a hunger strike. Strakhov is General Director of UIPE, and Naumenko-Bondarenko is chairman of the Trade Union Committee of UIPE.In a press statement released on September 30 in Moscow, the geophysicists stated that they are striking to “protest the policy of the Government of the Russian Federation with regard to Russian science in general and to the Russian Academy of Sciences in particular.” They blame governmental neglect and, specifically, “the non-payment of funds that were in the 1996 budget” for the “virtual collapse of Russian science.”

  11. Should junior doctors strike?

    PubMed

    Toynbee, Mark; Al-Diwani, Adam Aj; Clacey, Joe; Broome, Matthew R

    2016-03-01

    An impasse in negotiations between the Department of Health (DoH) and the British Medical Association in November this year led to an overwhelming vote for industrial action (IA) by junior doctors. At the time of writing, a last minute concession by DoH led to a deferment of IA to allow further negotiations mediated by the Advisory, Conciliation and Arbitration Service. However, IA by junior doctors remains a possibility if these negotiations stall again. Would the proposed action be ethically justifiable? Furthermore, is IA by doctors ever ethically defendable? Building on previous work, we explore important ethical considerations for doctors considering IA. The primary moral objection to doctors striking is often claimed to be risk of harm to patients. Other common arguments against IA by doctors include breaching their vocational responsibilities and possible damage to their relationship with patients and the public in general. These positions are in turn countered by claims of a greater long-term good and the legal and moral rights of employees to strike. Absolute restrictions appear to be hard to justify in the modern context, as does an unrestricted right to IA. We review these arguments, find that some common moral objections to doctors striking may be less relevant to the current situation, that a stronger contemporary objection to IA might be from a position of social justice and suggest criteria for ethically permissible doctor IA. PMID:26758366

  12. Composite Lightning Rods for Aircraft

    NASA Technical Reports Server (NTRS)

    Bryan, Charles F., Jr.

    1986-01-01

    Composite, lightweight sacrificial tip with graphite designed reduces lightning-strike damage to composite parts of aircraft and dissipates harmful electrical energy. Device consists of slender composite rod fabricated from highly-conductive unidirectional reinforcing fibers in matrix material. Rods strategically installed in trailing edges of aircraft wings, tails, winglets, control surfaces, and rearward-most portion of aft fuselage.

  13. [Neurological diseases after lightning strike : Lightning strikes twice].

    PubMed

    Gruhn, K M; Knossalla, Frauke; Schwenkreis, Peter; Hamsen, Uwe; Schildhauer, Thomas A; Tegenthoff, Martin; Sczesny-Kaiser, Matthias

    2016-06-01

    Lightning strikes rarely occur but 85 % of patients have lightning-related neurological complications. This report provides an overview about different modes of energy transfer and neurological conditions related to lightning strikes. Moreover, two case reports demonstrate the importance of interdisciplinary treatment and the spectrum of neurological complications after lightning strikes. PMID:26873252

  14. Lightning threat to aircraft: Do we know all we need to know?

    NASA Technical Reports Server (NTRS)

    Mazur, Vladislav

    1991-01-01

    The problem of lightning threat to aircraft has two aspects: strike avoidance and aircraft protection. These two issues are addressed under the following topics: (1) lightning strikes, weather conditions, and natural lightning rate; (2) the engineering vs. scientific approach to aircraft protection; and (3) the additional information needed to understand lightning threat to aircraft.

  15. Electrical Characterizations of Lightning Strike Protection Techniques for Composite Materials

    NASA Technical Reports Server (NTRS)

    Szatkowski, George N.; Nguyen, Truong X.; Koppen, Sandra V.; Ely, Jay J.; Mielnik, John J.

    2009-01-01

    The growing application of composite materials in commercial aircraft manufacturing has significantly increased the risk of aircraft damage from lightning strikes. Composite aircraft designs require new mitigation strategies and engineering practices to maintain the same level of safety and protection as achieved by conductive aluminum skinned aircraft. Researchers working under the NASA Aviation Safety Program s Integrated Vehicle Health Management (IVHM) Project are investigating lightning damage on composite materials to support the development of new mitigation, diagnosis & prognosis techniques to overcome the increased challenges associated with lightning protection on composite aircraft. This paper provides an overview of the electrical characterizations being performed to support IVHM lightning damage diagnosis research on composite materials at the NASA Langley Research Center.

  16. The Pullman Strike of 1894.

    ERIC Educational Resources Information Center

    Bassett, Jonathan

    1997-01-01

    Presents a lesson plan focused on the events surrounding the 1894 Pullman railroad car strike. Reviews the particulars of the strike (the federal government used armed force to end the strike) and then presents a simulation where students role play members of the investigating presidential commission. Includes related documents. (MJP)

  17. Atmospheric electrical modeling in support of the NASA F106 Storm Hazards Project

    NASA Technical Reports Server (NTRS)

    Helsdon, J. H.

    1986-01-01

    With the use of composite (non-metallic) and microelectronics becoming more prevalent in the construction of both military and commercial aircraft, the control systems have become more susceptible to damage or failure from electromagnetic transients. One source of such transients is the lightning discharge. In order to study the effects of the lightning discharge on the vital components of an aircraft, NASA Langley Research Center has undertaken a Storm Hazards Program in which a specially instrumented F106B jet aircraft is flown into active thunderstorms with the intention of being struck by lightning. One of the specific purposes of the program is to quantify the environmental conditions which are conductive to aircraft lightning strikes.

  18. Ophthalmic manifestations postlightning strike.

    PubMed

    Dhillon, Permesh Singh; Gupta, Mohit

    2015-01-01

    Various ophthalmic complications affecting the anterior and posterior segments have been identified due to lightning strike. We report the first case of an indirect lightning-induced full thickness macular hole formation in the UK as evidenced by slit lamp examination and optical coherence tomography (OCT) scan in a 77-year-old woman presenting with sudden visual loss in her right eye and thermal skin injury affecting her scalp. Her best corrected visual acuities were LogMAR 0.46 and 0.12 in the right and left eyes, respectively. There were no other ocular manifestations observed in either eye. She was initially managed conservatively with non-steroidal anti-inflammatory drug eye drops but surgery was later advised due to minimal changes in the visual acuity and macular hole on follow-up. OCT scanning is important in diagnosing macular holes, which usually warrant surgical intervention. PMID:25827914

  19. Where Lightning Strikes

    NASA Technical Reports Server (NTRS)

    2002-01-01

    Lightning. It avoids the ocean, but likes Florida. It's attracted to the Himalayas and even more so to central Africa. And lightning almost never strikes the north or south poles. These are just a few of the things NASA scientists have learned using satellites to monitor worldwide lightning. 'For the first time, we've been able to map the global distribution of lightning, noting its variation as a function of latitude, longitude and time of year,' says Hugh Christian, project leader for the National Space Science and Technology Center's (NSSTC's) lightning team at NASA's Marshall Space Flight Center. This new perspective on lightning is possible thanks to two satellite-based detectors: the Optical Transient Detector (OTD) and the Lightning Imaging Sensor (LIS). 'The OTD and the LIS are two optical sensors that we've flown in lower Earth orbit,' says Christian, whose team developed the sensors. 'The OTD was launched in 1995 and we got five good years out of it. The LIS was launched on the Tropical Rainfall Measuring Mission satellite in 1997 and it's still going strong.' 'Basically, these optical sensors use high-speed cameras to look for changes in the tops of clouds, changes your eyes can't see,' he explains. By analyzing a narrow wavelength band around 777 nanometers-which is in the near-infrared region of the spectrum-they can spot brief lightning flashes even under daytime conditions. For the full story, visit Science@NASA Image courtesy NSSTC Lightning Team

  20. 14 CFR 91.111 - Operating near other aircraft.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 14 Aeronautics and Space 2 2011-01-01 2011-01-01 false Operating near other aircraft. 91.111... § 91.111 Operating near other aircraft. (a) No person may operate an aircraft so close to another aircraft as to create a collision hazard. (b) No person may operate an aircraft in formation flight...

  1. 14 CFR 91.111 - Operating near other aircraft.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 14 Aeronautics and Space 2 2012-01-01 2012-01-01 false Operating near other aircraft. 91.111... § 91.111 Operating near other aircraft. (a) No person may operate an aircraft so close to another aircraft as to create a collision hazard. (b) No person may operate an aircraft in formation flight...

  2. 14 CFR 91.111 - Operating near other aircraft.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 14 Aeronautics and Space 2 2014-01-01 2014-01-01 false Operating near other aircraft. 91.111... § 91.111 Operating near other aircraft. (a) No person may operate an aircraft so close to another aircraft as to create a collision hazard. (b) No person may operate an aircraft in formation flight...

  3. 14 CFR 91.111 - Operating near other aircraft.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 14 Aeronautics and Space 2 2013-01-01 2013-01-01 false Operating near other aircraft. 91.111... § 91.111 Operating near other aircraft. (a) No person may operate an aircraft so close to another aircraft as to create a collision hazard. (b) No person may operate an aircraft in formation flight...

  4. 14 CFR 91.111 - Operating near other aircraft.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 14 Aeronautics and Space 2 2010-01-01 2010-01-01 false Operating near other aircraft. 91.111... § 91.111 Operating near other aircraft. (a) No person may operate an aircraft so close to another aircraft as to create a collision hazard. (b) No person may operate an aircraft in formation flight...

  5. 49 CFR 175.26 - Notification at cargo facilities of hazardous materials requirements.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... aircraft must be offered in accordance with the Federal Hazardous Materials Regulations (49 CFR parts 171... PIPELINE AND HAZARDOUS MATERIALS SAFETY ADMINISTRATION, DEPARTMENT OF TRANSPORTATION HAZARDOUS...

  6. 49 CFR 175.26 - Notification at cargo facilities of hazardous materials requirements.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... aircraft must be offered in accordance with the Federal Hazardous Materials Regulations (49 CFR parts 171... PIPELINE AND HAZARDOUS MATERIALS SAFETY ADMINISTRATION, DEPARTMENT OF TRANSPORTATION HAZARDOUS...

  7. Lightning attachment patterns and flight conditions for storm hazards, 1980

    NASA Technical Reports Server (NTRS)

    Fisher, B. D.; Keyser, G. L., Jr.; Deal, P. L.

    1982-01-01

    As part of the NASA Langley Research Center Storm Hazards Program, 69 thunderstorm pentrations were made in 1980 with an F-106B airplane in order to record direct strike lightning data and the associated flight conditions. Ground based weather radar measurements in conjunction with these penetrations were made by NOAA National Severe Storms Laboratory in Oklahoma and by NASA Wallops Flight Center in Virginia. In 1980, the airplane received 10 direct lightning strikes; in addition, lightning transient data were recorded from 6 nearby flashes. Following each flight, the airplane was thoroughly inspected for evidence of lightning attachment, and the individual lightning attachment points were plotted on isometric projections of the airplane to identify swept flash patterns. This report presents pilot descriptions of the direct strikes to the airplane, shows the strike attachment patterns that were found, and discusses the implications of the patterns with respect to aircraft protection design. The flight conditions are also included. Finally, the lightning strike scenarios for three U.S. Air Force F-106A airplanes which were struck during routine operations are given in the appendix to this paper.

  8. Hazards in the theater.

    PubMed

    Rossol, M; Hinkamp, D

    2001-01-01

    The authors offer a survey of the myriad and unique safety and health hazards faced past and present by performers and theatrical workers, from preproduction work, through the show, and during the strike (dismantling). Special emphasis is given to health hazards posed by the many new plastic resin systems and adhesives used in set, prop, and costume construction; the hazards of special-effect fogs, smokes, haze, dusts, and pyrotechnic emissions; and theatrical makeup. PMID:11567920

  9. Modern Protection Against Lightning Strikes

    NASA Astrophysics Data System (ADS)

    Moore, C.

    2005-05-01

    The application of science to provide protection against lightning strikes began around 1750 when Benjamin Franklin who invented the lightning rod in an effort to discharge thunderclouds. Instead of preventing lightning as he expected, his rods have been quite successful as strike receptors, intercepting cloud-to ground discharges and conducting them to Earth without damage to the structures on which they are mounted. In the years since Franklin's invention there has been little attention paid to the rod configuration that best serves as a strike receptor but Franklin's original ideas continue to be rediscovered and promoted. Recent measurements of the responses of variously configured rods to nearby strikes indicate that sharp-tipped rods are not the optimum configuration to serve as strike receptors since the ionization of the air around their tips limits the strength of the local electric fields created by an approaching lightning leader. In these experiments, fourteen blunt-tipped rods exposed in strike-reception competitions with nearby sharp-tipped rods were struck by lightning but none of the sharp-tipped rods were struck.

  10. Physicians' changing attitudes about striking.

    PubMed

    Wassertheil-Smoller, S; Croen, L; Siegel, B

    1979-01-01

    Both interns and residents and practicing physicians express substantial support for physicians' organizing for collective bargaining and striking. These findings, from 1146 respondents to a 1976 survey of the alumni of the Albert Einstein College of Medicine, indicate that profound changes have occurred in physicians' views on these issues. Although the greatest support for striking came from interns and residents, with 67 per cent of them indicating they think physicians should be allowed to strike, the survey found an increasing pattern of militancy commencing with 1964 graduates. Physicians in private practice and those who spent two-thirds or more of their time in direct patient care were the most likely to support strikes by physicians (60 per cent), while the least support came from those fulltime on medical school faculties (39 per cent). No differences in support for striking were found in relation to sex, religion or size of community in which physicians practice. A longitudinal examination of the medical school Class of 1975 at matriculation, at graduation and during internship training reveals that a major growth of support for striking occurred between matriculation and graduation. PMID:759745

  11. Development, Implementation, and Pilot Evaluation of a Model-Driven Envelope Protection System to Mitigate the Hazard of In-Flight Ice Contamination on a Twin-Engine Commuter Aircraft

    NASA Technical Reports Server (NTRS)

    Martos, Borja; Ranaudo, Richard; Norton, Billy; Gingras, David; Barnhart, Billy

    2014-01-01

    Fatal loss-of-control accidents have been directly related to in-flight airframe icing. The prototype system presented in this report directly addresses the need for real-time onboard envelope protection in icing conditions. The combination of prior information and real-time aerodynamic parameter estimations are shown to provide sufficient information for determining safe limits of the flight envelope during inflight icing encounters. The Icing Contamination Envelope Protection (ICEPro) system was designed and implemented to identify degradations in airplane performance and flying qualities resulting from ice contamination and provide safe flight-envelope cues to the pilot. The utility of the ICEPro system for mitigating a potentially hazardous icing condition was evaluated by 29 pilots using the NASA Ice Contamination Effects Flight Training Device. Results showed that real time assessment cues were effective in reducing the number of potentially hazardous upset events and in lessening exposure to loss of control following an incipient upset condition. Pilot workload with the added ICEPro displays was not measurably affected, but pilot opinion surveys showed that real time cueing greatly improved their awareness of a hazardous aircraft state. The performance of ICEPro system was further evaluated by various levels of sensor noise and atmospheric turbulence.

  12. First strike: myth or reality

    SciTech Connect

    Anderson, J.E.

    1981-11-01

    Before accepting the military establishment's belief that alleged Soviet first-strike capability makes the MX program urgent, it is worthwhile to examine both the evidence and the conclusion. Using unclassified information, the author examines the arguments in terms of what kind of attack the Soviets might make, how the attack will affect the Soviet Union, missile testing, the real-kill probability, the miss probability, and the perception of a threat and sees little justification for confidence in the results of a first strike. He feels, however, that administration beliefs will be based on intuition and ideology rather than technical assessment. That, coupled with the acknowledged first-strike capability of the US, increases the danger. 12 references. (DCK)

  13. [Physicians' strikes--ethical considerations].

    PubMed

    Glick, Shimon; Schwarzfuchs, Dan

    2012-01-01

    Strikes in general represent a solution based on a form of coercion. Historically, the striker caused direct damage to his employer, who was responsible for the perceived unfair treatment of the employee. In the case of strikes in the public sector, the employer is generally not harmed, but innocent citizens suffer in order to pressure the government agencies, a questionable practice from an ethical viewpoint. Physicians' strikes have more serious ethical problems. They cause suffering and death to innocent citizens. They violate the ethical codes to which physicians have committed themselves as professionals, and they seriously impair the trust of the public in physicians. Better and more ethical ways to provide fair compensation for physicians must be employed, perhaps like those used for judges and members of the IDF. PMID:22670493

  14. Soviet KIROV class strike cruiser

    SciTech Connect

    Kehoe, J.W.; Brower, K.S.; Meier, H.A.

    1981-04-01

    The major design concepts and basic characteristics of the Soviet KIROV Class ship, an impressive nuclear-powered Strike Cruiser which recently appeared while undergoing sea trials in the Baltic Sea and the North Sea, are discussed. Highlights are presented of the KIROV's hull form, the weapons, electronics and aviation systems, machinery, as well as the cruiser's speed and range.

  15. Communicating During Negotiations/Strikes.

    ERIC Educational Resources Information Center

    National School Public Relations Association, Arlington, VA.

    Successful collective bargaining and, if necessary, strike management, requires careful planned communication strategies and programs before, during, and after, if the school system is to maintain the public's confidence. This handbook is designed to provide guidelines for the educational administrative team in developing a communication plan that…

  16. The Teachers' Strike Study. Sudbury, Ontario, 1980.

    ERIC Educational Resources Information Center

    Radecki, Henry; Evans, Susan

    Focusing on the 1980 strike of public secondary school teachers in Sudbury, Ontario, this study examined attitudes of those involved; ascertained feelings toward the school system that may have emerged since the strike; and examined events, influences, and developments leading to the strike and prolonging the strike. The field study represented…

  17. Follow-up Survey of Strike Impact.

    ERIC Educational Resources Information Center

    Grayson, J. Paul

    During a faculty strike at York University (Ontario), two telephone surveys were undertaken to assess student perceptions of the strike. The first survey was taken during the fifth and sixth weeks of the strike, with the objective of documenting the experiences of students while the strike was on. The questionnaire for this survey was developed…

  18. Takotsubo cardiomyopathy following lightning strike.

    PubMed

    Dundon, B K; Puri, R; Leong, D P; Worthley, M I

    2008-07-01

    Lightning strike is the most common environmental cause of sudden cardiac death, but may also be associated with a myriad of injuries to various organ systems. Direct myocardial injury may be manifest as electrocardiographic alterations or elevation in cardiac-specific isoenzymes; however, significant electrical cardiac trauma appears uncommon. A case is presented of severe acute cardiomyopathy in a "Takotsubo" distribution causing cardiogenic shock following lightning strike in a previously healthy 37-year-old woman. Although rarely identified in this context, Takotsubo cardiomyopathy (also known as "transient left ventricular apical ballooning syndrome") is characterised by transient cardiac dysfunction, electrocardiographic changes that may mimic acute myocardial infarction and minimal release of cardiac-specific enzymes in the absence of obstructive coronary artery disease. The condition is associated with a substantial female bias (up to 90% of cases) in reported series, and despite occasionally dramatic presentations recovery of left ventricular function is almost universal over days to weeks. In rare instances, however, the syndrome has been associated with more catastrophic complications such as papillary muscle or cardiac free wall rupture, necessitating emergency surgical intervention to preserve life. In clinical practice, non-lethal lightning strike-induced cardiac injury is frequently associated with small elevations of cardiac isoenzymes without overt clinical sequelae; however, the incidence of silent myocardial mechanical dysfunction remains unknown. Cases such as the one presented highlight the potential for serious, albeit usually transient, cardiac sequelae from lightning strike injury and remind us that our mothers' advice to remain indoors during thunderstorms is probably worth heeding. PMID:18573973

  19. Takotsubo cardiomyopathy following lightning strike.

    PubMed

    Dundon, Benjamin K; Puri, Rishi; Leong, Darryl P; Worthley, Matthew Ian

    2009-01-01

    Lightning strike is the most common environmental cause of sudden cardiac death, but it may also be associated with a myriad of injuries to various organ systems. Direct myocardial injury may be manifest as electrocardiographic alterations or elevation in cardiac-specific isoenzymes; however, significant electrical cardiac trauma appears uncommon. A case is presented of severe acute cardiomyopathy in a "Takotsubo" distribution causing cardiogenic shock following lightning strike in a previously healthy 37-year-old woman. Although rarely identified in this context, Takotsubo cardiomyopathy (also known as "transient left ventricular apical ballooning syndrome") is characterised by transient cardiac dysfunction, electrocardiographic changes that may mimic acute myocardial infarction and minimal release of cardiac-specific enzymes in the absence of obstructive coronary artery disease. The condition is associated with a substantial female bias (up to 90% of cases) in reported series, and despite occasionally dramatic presentations recovery of left ventricular function is almost universal over days to weeks. In rare instances, however, the syndrome has been associated with more catastrophic complications such as papillary muscle or cardiac free wall rupture, necessitating emergency surgical intervention to preserve life. In clinical practice, non-lethal lightning strike-induced cardiac injury is frequently associated with small elevations of cardiac isoenzymes without overt clinical sequelae; however, the incidence of silent myocardial mechanical dysfunction remains unknown. Cases such as the one presented highlight the potential for serious, albeit usually transient, cardiac sequelae from lightning strike injury and remind us that our mothers' advice to remain indoors during thunderstorms is probably worth heeding. PMID:21686980

  20. Civil helicopter wire strike assessment study. Volume 1: Findings and recommendations

    NASA Technical Reports Server (NTRS)

    Tuomela, C. H.; Brennan, M. F.

    1980-01-01

    Approximately 208 civil helicopter wire strike accidents for a ten year period 1970 to 1979 are analyzed. It is found that 83% of the wire strikes occurred during bright clear weather. Analysis of the accidents is organized under pilot, environment, and machine factors. Methods to reduce the wire strike accident rate are discussed, including detection/warning devices, identification of wire locations prior to flight, wire cutting devices, and implementation of training programs. The benefits to be gained by implementing accident avoidance methods are estimated to be fully justified by reduction in injury and death and reduction of aircraft damage and loss.

  1. Wind shear hazard determination

    NASA Technical Reports Server (NTRS)

    Lewis, Michael S.

    1992-01-01

    The topics are presented in viewgraph form and include the following: F-factor relationship with aircraft performance; F-factor formulations; the F-bar index; F-factor hazard limit; F-bar with Doppler sensors; and F-bar profile composite.

  2. Lightning strike at Bryan, Ohio

    SciTech Connect

    Nichols, B. E.

    1980-02-01

    A week before the 29 August 1979 dedication of the photovoltaic power system at daytime AM radio station WBNO, in Bryan, Ohio, a lightning superbolt struck the FM radio tower, one of two towers at the station. Minor damage to the station and to components of the photovoltaic system, the latter designed by MIT Lincoln Laboratory under US Department of Energy sponsorship, is described. This rare strike suggested the need for increased protection and more voltage-transient suppressors were added to those already in place as a preventive measure in the event that such a phenomenon reoccurs.

  3. The feasibility of inflight measurement of lightning strike parameters

    NASA Technical Reports Server (NTRS)

    Crouch, K. E.; Plumer, J. A.

    1978-01-01

    The appearance of nonmetallic structural materials and microelectronics in aircraft design has resulted in a need for better knowledge of hazardous environments such as lightning and the effects these environments have on the aircraft. This feasibility study was performed to determine the lightning parameters in the greatest need of clarification and the performance requirements of equipment necessary to sense and record these parameters on an instrumented flight research aircraft. It was found that electric field rate of change, lightning currents, and induced voltages in aircraft wiring are the parameters of greatest importance. Flat-plate electric field sensors and resistive current shunts are proposed for electric field and current sensors, to provide direct measurements of these parameters. Six bit analog-to-digital signal conversion at a 5 nanosecond sampling rate, short-term storage of 85000 bits and long term storage of 5 x 10 to the 7th power bits of electric field, current and induced voltage data on the airplane are proposed, with readout and further analysis to be accomplished on the ground. A NASA F-106B was found to be suitable for use as the research aircraft because it has a minimum number of possible lightning attachment points, space for the necessary instrumentation, and appears to meet operational requirements. Safety considerations are also presented.

  4. Doctors' strikes and mortality: a review.

    PubMed

    Cunningham, Solveig Argeseanu; Mitchell, Kristina; Narayan, K M; Yusuf, Salim

    2008-12-01

    A paradoxical pattern has been suggested in the literature on doctors' strikes: when health workers go on strike, mortality stays level or decreases. We performed a review of the literature during the past forty years to assess this paradox. We used PubMed, EconLit and Jstor to locate all peer-reviewed English-language articles presenting data analysis on mortality associated with doctors' strikes. We identified 156 articles, seven of which met our search criteria. The articles analyzed five strikes around the world, all between 1976 and 2003. The strikes lasted between nine days and seventeen weeks. All reported that mortality either stayed the same or decreased during, and in some cases, after the strike. None found that mortality increased during the weeks of the strikes compared to other time periods. The paradoxical finding that physician strikes are associated with reduced mortality may be explained by several factors. Most importantly, elective surgeries are curtailed during strikes. Further, hospitals often re-assign scarce staff and emergency care was available during all of the strikes. Finally, none of the strikes may have lasted long enough to assess the effects of long-term reduced access to a physician. Nonetheless, the literature suggests that reductions in mortality may result from these strikes. PMID:18849101

  5. 31 CFR 0.202 - Strikes.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 31 Money and Finance: Treasury 1 2012-07-01 2012-07-01 false Strikes. 0.202 Section 0.202 Money and Finance: Treasury Office of the Secretary of the Treasury DEPARTMENT OF THE TREASURY EMPLOYEE RULES OF CONDUCT Rules of Conduct § 0.202 Strikes. Employees shall not strike against the Government....

  6. 31 CFR 0.202 - Strikes.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 31 Money and Finance: Treasury 1 2013-07-01 2013-07-01 false Strikes. 0.202 Section 0.202 Money and Finance: Treasury Office of the Secretary of the Treasury DEPARTMENT OF THE TREASURY EMPLOYEE RULES OF CONDUCT Rules of Conduct § 0.202 Strikes. Employees shall not strike against the Government....

  7. 31 CFR 0.202 - Strikes.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 31 Money and Finance: Treasury 1 2011-07-01 2011-07-01 false Strikes. 0.202 Section 0.202 Money and Finance: Treasury Office of the Secretary of the Treasury DEPARTMENT OF THE TREASURY EMPLOYEE RULES OF CONDUCT Rules of Conduct § 0.202 Strikes. Employees shall not strike against the Government....

  8. 31 CFR 0.202 - Strikes.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 31 Money and Finance: Treasury 1 2014-07-01 2014-07-01 false Strikes. 0.202 Section 0.202 Money and Finance: Treasury Office of the Secretary of the Treasury DEPARTMENT OF THE TREASURY EMPLOYEE RULES OF CONDUCT Rules of Conduct § 0.202 Strikes. Employees shall not strike against the Government....

  9. 31 CFR 0.202 - Strikes.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 31 Money and Finance: Treasury 1 2010-07-01 2010-07-01 false Strikes. 0.202 Section 0.202 Money and Finance: Treasury Office of the Secretary of the Treasury DEPARTMENT OF THE TREASURY EMPLOYEE RULES OF CONDUCT Rules of Conduct § 0.202 Strikes. Employees shall not strike against the Government....

  10. Aircraft Design

    NASA Technical Reports Server (NTRS)

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

    2016-01-01

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

  11. Aircraft Noise

    NASA Astrophysics Data System (ADS)

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

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

  12. Simulation Tools Model Icing for Aircraft Design

    NASA Technical Reports Server (NTRS)

    2012-01-01

    Here s a simple science experiment to try: Place an unopened bottle of distilled water in your freezer. After 2-3 hours, if the water is pure enough, you will notice that it has not frozen. Carefully pour the water into a bowl with a piece of ice in it. When it strikes the ice, the water will instantly freeze. One of the most basic and commonly known scientific facts is that water freezes at around 32 F. But this is not always the case. Water lacking any impurities for ice crystals to form around can be supercooled to even lower temperatures without freezing. High in the atmosphere, water droplets can achieve this delicate, supercooled state. When a plane flies through clouds containing these droplets, the water can strike the airframe and, like the supercooled water hitting the ice in the experiment above, freeze instantly. The ice buildup alters the aerodynamics of the plane - reducing lift and increasing drag - affecting its performance and presenting a safety issue if the plane can no longer fly effectively. In certain circumstances, ice can form inside aircraft engines, another potential hazard. NASA has long studied ways of detecting and countering atmospheric icing conditions as part of the Agency s efforts to enhance aviation safety. To do this, the Icing Branch at Glenn Research Center utilizes a number of world-class tools, including the Center s Icing Research Tunnel and the NASA 607 icing research aircraft, a "flying laboratory" for studying icing conditions. The branch has also developed a suite of software programs to help aircraft and icing protection system designers understand the behavior of ice accumulation on various surfaces and in various conditions. One of these innovations is the LEWICE ice accretion simulation software. Initially developed in the 1980s (when Glenn was known as Lewis Research Center), LEWICE has become one of the most widely used tools in icing research and aircraft design and certification. LEWICE has been transformed over

  13. A Windshear Hazard Index

    NASA Technical Reports Server (NTRS)

    Proctor, Fred H.; Hinton, David A.; Bowles, Roland L.

    2000-01-01

    An aircraft exposed to hazardous low-level windshear may suffer a critical loss of airspeed and altitude, thus endangering its ability to remain airborne. In order to characterize this hazard, a nondimensional index was developed based oil aerodynamic principals and understanding of windshear phenomena, 'This paper reviews the development and application of the Bowles F-tactor. which is now used by onboard sensors for the detection of hazardous windshear. It was developed and tested during NASA/I:AA's airborne windshear program and is now required for FAA certification of onboard radar windshear detection systems. Reviewed in this paper are: 1) definition of windshear and description of atmospheric phenomena that may cause hazardous windshear. 2) derivation and discussion of the F-factor. 3) development of the F-factor hazard threshold, 4) its testing during field deployments, and 5) its use in accident reconstructions,

  14. Estimation of Damage Preference From Strike Parameters

    SciTech Connect

    Canavan, G.H.

    1998-09-11

    Estimation of an opponent's damage preference is illustrated by discussing the sensitivity of stability indices and strike parameters to it and inverting the results to study the sensitivity of estimates to uncertainties in strikes. Costs and stability indices do not generally have the monotonicity and sensitivity needed to support accurate estimation. First and second strikes do. Second strikes also have proportionality, although they are not unambiguously interpretable. First strikes are observable and have the greatest overall power for estimation, whether linear or numerical solutions are used.

  15. Behavioral Traits and Airport Type Affect Mammal Incidents with U.S. Civil Aircraft

    NASA Astrophysics Data System (ADS)

    Schwarz, Kristin B.; Belant, Jerrold L.; Martin, James A.; DeVault, Travis L.; Wang, Guiming

    2014-10-01

    Wildlife incidents with aircraft cost the United States (U.S.) civil aviation industry >US1.4 billion in estimated damages and loss of revenue from 1990 to 2009. Although terrestrial mammals represented only 2.3 % of wildlife incidents, damage to aircraft occurred in 59 % of mammal incidents. We examined mammal incidents (excluding bats) at all airports in the Federal Aviation Administration (FAA) National Wildlife Strike Database from 1990 to 2010 to characterize these incidents by airport type: Part-139 certified (certificated) and general aviation (GA). We also calculated relative hazard scores for species most frequently involved in incidents. We found certificated airports had more than twice as many incidents as GA airports. Incidents were most frequent in October ( n = 215 of 1,764 total) at certificated airports and November ( n = 111 of 741 total) at GA airports. Most (63.2 %) incidents at all airports ( n = 1,523) occurred at night but the greatest incident rate occurred at dusk (177.3 incidents/hr). More incidents with damage ( n = 1,594) occurred at GA airports (38.6 %) than certificated airports (19.0 %). Artiodactyla (even-toed ungulates) incidents incurred greatest (92.4 %) damage costs ( n = 326; US51.8 million) overall and mule deer ( Odocoileus hemionus) was the most hazardous species. Overall, relative hazard score increased with increasing log body mass. Frequency of incidents was influenced by species relative seasonal abundance and behavior. We recommend airport wildlife officials evaluate the risks mammal species pose to aircraft based on the hazard information we provide and consider prioritizing management strategies that emphasize reducing their occurrence on airport property.

  16. Behavioral traits and airport type affect mammal incidents with U.S. civil aircraft.

    PubMed

    Schwarz, Kristin B; Belant, Jerrold L; Martin, James A; DeVault, Travis L; Wang, Guiming

    2014-10-01

    Wildlife incidents with aircraft cost the United States (U.S.) civil aviation industry >US$1.4 billion in estimated damages and loss of revenue from 1990 to 2009. Although terrestrial mammals represented only 2.3 % of wildlife incidents, damage to aircraft occurred in 59 % of mammal incidents. We examined mammal incidents (excluding bats) at all airports in the Federal Aviation Administration (FAA) National Wildlife Strike Database from 1990 to 2010 to characterize these incidents by airport type: Part-139 certified (certificated) and general aviation (GA). We also calculated relative hazard scores for species most frequently involved in incidents. We found certificated airports had more than twice as many incidents as GA airports. Incidents were most frequent in October (n = 215 of 1,764 total) at certificated airports and November (n = 111 of 741 total) at GA airports. Most (63.2 %) incidents at all airports (n = 1,523) occurred at night but the greatest incident rate occurred at dusk (177.3 incidents/hr). More incidents with damage (n = 1,594) occurred at GA airports (38.6 %) than certificated airports (19.0 %). Artiodactyla (even-toed ungulates) incidents incurred greatest (92.4 %) damage costs (n = 326; US$51.8 million) overall and mule deer (Odocoileus hemionus) was the most hazardous species. Overall, relative hazard score increased with increasing log body mass. Frequency of incidents was influenced by species relative seasonal abundance and behavior. We recommend airport wildlife officials evaluate the risks mammal species pose to aircraft based on the hazard information we provide and consider prioritizing management strategies that emphasize reducing their occurrence on airport property. PMID:25082299

  17. Fireworthiness of transport aircraft interior systems

    NASA Technical Reports Server (NTRS)

    Parker, J. A.; Kourtides, D. A.

    1982-01-01

    The fire worthiness of air transport interiors was evaluated. The effect of interior systems on the survival of passengers and crew in an uncontrolled transport aircraft fire is addressed. Modification of aircraft interior subsystem components which provide improvements in aircraft fire safety are examined. Three specific subsystem components, interior panels, seats and windows, offer the most immediate and highest payoff by modifying interior materials of existing aircrafts. It is shown that the new materials modifications reduce the fire hazards because of significant reduction in their characteristic flame spread, heat release, and smoke and toxic gas emissions.

  18. 14 CFR 29.631 - Bird strike.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 14 Aeronautics and Space 1 2012-01-01 2012-01-01 false Bird strike. 29.631 Section 29.631... STANDARDS: TRANSPORT CATEGORY ROTORCRAFT Design and Construction General § 29.631 Bird strike. The... safe landing (for Category B) after impact with a 2.2-lb (1.0 kg) bird when the velocity of...

  19. 14 CFR 29.631 - Bird strike.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 14 Aeronautics and Space 1 2013-01-01 2013-01-01 false Bird strike. 29.631 Section 29.631... STANDARDS: TRANSPORT CATEGORY ROTORCRAFT Design and Construction General § 29.631 Bird strike. The... safe landing (for Category B) after impact with a 2.2-lb (1.0 kg) bird when the velocity of...

  20. 14 CFR 29.631 - Bird strike.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 14 Aeronautics and Space 1 2014-01-01 2014-01-01 false Bird strike. 29.631 Section 29.631... STANDARDS: TRANSPORT CATEGORY ROTORCRAFT Design and Construction General § 29.631 Bird strike. The... safe landing (for Category B) after impact with a 2.2-lb (1.0 kg) bird when the velocity of...

  1. The Strike from the Students' Viewpoint.

    ERIC Educational Resources Information Center

    Grayson, J. Paul

    In the fifth and sixth weeks of a faculty strike at York University (Ontario), a survey was undertaken to assess student perceptions of the strike, its benefits, and its costs. Respondents were 502 randomly selected full-time undergraduate students in several disciplines. Survey questions were developed in student focus groups. The report…

  2. 14 CFR 29.631 - Bird strike.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 14 Aeronautics and Space 1 2011-01-01 2011-01-01 false Bird strike. 29.631 Section 29.631... STANDARDS: TRANSPORT CATEGORY ROTORCRAFT Design and Construction General § 29.631 Bird strike. The... safe landing (for Category B) after impact with a 2.2-lb (1.0 kg) bird when the velocity of...

  3. 14 CFR 29.631 - Bird strike.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Bird strike. 29.631 Section 29.631... STANDARDS: TRANSPORT CATEGORY ROTORCRAFT Design and Construction General § 29.631 Bird strike. The... safe landing (for Category B) after impact with a 2.2-lb (1.0 kg) bird when the velocity of...

  4. STOL Aircraft

    NASA Technical Reports Server (NTRS)

    1988-01-01

    Michael E. Fisher, President of AeroVisions International, has introduced the Culex light twin engine aircraft which offers economy of operation of a single engine plane, the ability to fly well on one engine, plus the capability of flying from short, unimproved fields of takeoff and landing distances less than 35 feet. Key element of design is an airfoil developed by Langley. Culex was originally intended to be factory built aircraft for special utility markets. However, it is now offered as a build-it-yourself kit plane.

  5. Aircraft cybernetics

    NASA Technical Reports Server (NTRS)

    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.

  6. Characteristics of civil aviation atmospheric hazards

    NASA Technical Reports Server (NTRS)

    Marshall, Robert E.; Montoya, J.; Richards, Mark A.; Galliano, J.

    1994-01-01

    Clear air turbulence, wake vortices, dry hail, and volcanic ash are hazards to civil aviation that have not been brought to the forefront of public attention by a catastrophic accident. However, these four hazards are responsible for major and minor injuries, emotional trauma, significant aircraft damage, and in route and terminal area inefficiency. Most injuries occur during clear air turbulence. There is significant aircraft damage for any volcanic ash encounter. Rolls induced by wake vortices occur near the ground. Dry hail often appears as an area of weak echo on the weather radar. This paper will present the meteorological, electromagnetic, and spatiotemporal characteristics of each hazard. A description of a typical aircraft encounter with each hazard will be given. Analyzed microwave and millimeter wave sensor systems to detect each hazard will be presented.

  7. Ball lightning risk to aircraft

    NASA Astrophysics Data System (ADS)

    Doe, R.; Keul, A.

    2009-04-01

    Lightning is a rare but regular phenomenon for air traffic. Aircraft are designed to withstand lightning strikes. Research on lightning and aircraft can be called detailed and effective. In the last 57 years, 18 reported lightning aviation disasters with a fatality figure of at least 714 persons occurred. For comparison, the last JACDEC ten-year average fatality figure was 857. The majority encountered lightning in the climb, descent, approach and/or landing phase. Ball lightning, a metastable, rare lightning type, is also seen from and even within aircraft, but former research only reported individual incidents and did not generate a more detailed picture to ascertain whether it constitutes a significant threat to passenger and aircraft safety. Lacking established incident report channels, observations were often only passed on as "air-travel lore". In an effort to change this unsatisfactory condition, the authors have collected a first international dataset of 38 documented ball lightning aircraft incidents from 1938 to 2001 involving 13 reports over Europe, 13 over USA/Canada, and 7 over Russia. 18 (47%) reported ball lightning outside the aircraft, 18 (47%) inside, 2 cases lacked data. 8 objects caused minor damage, 8 major damage (total: 42%), only one a crash. No damage was reported in 18 cases. 3 objects caused minor crew injury. In most cases, ball lightning lasted several seconds. 11 (29%) incidents ended with an explosion of the object. A cloud-aircraft lightning flash was seen in only 9 cases (24%) of the data set. From the detailed accounts of air personnel in the last 70 years, it is evident that ball lightning is rarely, but consistently observed in connection with aircraft and can also occur inside the airframe. Reports often came from multiple professional witnesses and in several cases, damages were investigated by civil or military authorities. Although ball lightning is no main air traffic risk, the authors suggest that incident and accident

  8. Hazardous Waste

    MedlinePlus

    ... you throw these substances away, they become hazardous waste. Some hazardous wastes come from products in our homes. Our garbage can include such hazardous wastes as old batteries, bug spray cans and paint ...

  9. Beyond the basics: lightning-strike injuries.

    PubMed

    Mistovich, Joseph J; Krost, William S; Limmer, Daniel D

    2008-03-01

    It is estimated that a lightning flash occurs approximately 8 million times per day throughout the world. Most strikes are benign and cause little damage to property and physical structures; however, when lightning strikes a person or group of people, it is a significant medical and potentially traumatic event that could lead to immediate death or permanent disability. By understanding some basic physics of lightning and pathophysiology of injuries associated with lightning strikes, EMS providers will be better prepared to identify assessment findings, anticipate complications and provide effective emergency care. PMID:18814638

  10. System and Method of Locating Lightning Strikes

    NASA Technical Reports Server (NTRS)

    Medelius, Pedro J. (Inventor); Starr, Stanley O. (Inventor)

    2002-01-01

    A system and method of determining locations of lightning strikes has been described. The system includes multiple receivers located around an area of interest, such as a space center or airport. Each receiver monitors both sound and electric fields. The detection of an electric field pulse and a sound wave are used to calculate an area around each receiver in which the lighting is detected. A processor is coupled to the receivers to accurately determine the location of the lighting strike. The processor can manipulate the receiver data to compensate for environmental variables such as wind, temperature, and humidity. Further, each receiver processor can discriminate between distant and local lightning strikes.

  11. Lightning Strike in Pregnancy With Fetal Injury.

    PubMed

    Galster, Kellen; Hodnick, Ryan; Berkeley, Ross P

    2016-06-01

    Injuries from lightning strikes are an infrequent occurrence, and are only rarely noted to involve pregnant victims. Only 13 cases of lightning strike in pregnancy have been previously described in the medical literature, along with 7 additional cases discovered within news media reports. This case report presents a novel case of lightning-associated injury in a patient in the third trimester of pregnancy, resulting in fetal ischemic brain injury and long-term morbidity, and reviews the mechanics of lightning strikes along with common injury patterns of which emergency providers should be aware. PMID:27116922

  12. Lightning Science: Five Ways Lightning Strikes People

    MedlinePlus

    ... Centers Products and Services Contact Us Glossary Lightning Science: Five Ways Lightning Strikes People It is not ... of a streamer injury. For more on the science of lightning: National Severe Storms Laboratory NWS Colorado ...

  13. Heart Attacks Striking Younger, Fatter Americans

    MedlinePlus

    ... nlm.nih.gov/medlineplus/news/fullstory_157946.html Heart Attacks Striking Younger, Fatter Americans: Study Doctors, patients need ... 24, 2016 THURSDAY, March 24, 2016 (HealthDay News) -- Heart attack victims in the United States are becoming younger ...

  14. Aircraft Lightning Electromagnetic Environment Measurement

    NASA Technical Reports Server (NTRS)

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

    2011-01-01

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

  15. Issues and Outcomes of Teachers' Strikes, 1955-65.

    ERIC Educational Resources Information Center

    Goergen, Joseph H.; Keough, John J.

    This study analyzes the patterns of 40 teacher strikes between 1955 and 1965 by looking at (1) the issues and demands and (2) the outcomes and settlements. It is hypothesized that (1) teacher strikes fall into discernible patterns, (2) functional relationships exist between certain strike issues and outcomes and the strike itself, (3) strikes can…

  16. When Push Comes to Shove: Strikes in Higher Education.

    ERIC Educational Resources Information Center

    Magney, John

    2002-01-01

    To provide a better sense of how academic unions handle a strike situation, examines six unions who, between 1996 and 2000, went through strikes. Discusses the key issues and outcomes of the strikes. (EV)

  17. VARIATION OF STRIKE INCENTIVES WITH DAMAGE PREFERENCES

    SciTech Connect

    G. CANAVAN

    2001-08-01

    For START III level forces, strike allocations and magnitudes vary little with L, but first strike costs vary directly with L, which means that for K reflecting a preference for the survival of high value targets over their destruction and a preference for high value over military targets, the costs of action are far greater than those of inaction for a wide range of values of damage preference L. Thus, if both sides have much greater preferences for the survival of their high value targets than for military targets or destruction, they do not see a net incentive to strike, and crises are terminated by inaction. Recent decades suggest strong preferences for the survival of high value and that this has contributed to the lack of direct conflict during that period.

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

    NASA Astrophysics Data System (ADS)

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

    2016-04-01

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

  19. Wake-Vortex Hazards During Cruise

    NASA Technical Reports Server (NTRS)

    Rossow, Vernon J.; James, Kevin D.; Nixon, David (Technical Monitor)

    1998-01-01

    Even though the hazard posed by lift-generated wakes of subsonic transport aircraft has been studied extensively for approach and departure at airports, only a small amount of effort has gone into the potential hazard at cruise altitude. This paper reports on a studio of the wake-vortex hazard during cruise because encounters may become more prevalent when free-flight becomes available and each aircraft, is free to choose its own route between destinations. In order to address the problem, the various fluid-dynamic stages that vortex wakes usually go through as they age will be described along with estimates of the potential hazard that each stage poses. It appears that a rolling-moment hazard can be just as severe at cruise as for approach at airports, but it only persists for several minutes. However, the hazard posed by the downwash in the wake due to the lift on the generator aircraft persists for tens of minutes in a long narrow region behind the generating aircraft. The hazard consists of severe vertical loads when an encountering aircraft crosses the wake. A technique for avoiding vortex wakes at cruise altitude will be described. To date the hazard posed by lift-generated vortex wakes and their persistence at cruise altitudes has been identified and subdivided into several tasks. Analyses of the loads to be encounter and are underway and should be completed shortly. A review of published literature on the subject has been nearly completed (see text) and photographs of vortex wakes at cruise altitudes have been taken and the various stages of decay have been identified. It remains to study and sort the photographs for those that best illustrate the various stages of decay after they are shed by subsonic transport aircraft at cruise altitudes. The present status of the analysis and the paper are described.

  20. 49 CFR 175.9 - Special aircraft operations.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... aircraft. Operators must have all applicable requirements prescribed in 14 CFR part 133 approved by the FAA... activation devices, lighting equipment, oxygen cylinders, flotation devices, smoke grenades, flares, or... aircraft. (4) Hazardous materials are carried and used during dedicated air ambulance, fire fighting,...

  1. 49 CFR 175.9 - Special aircraft operations.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... aircraft. Operators must have all applicable requirements prescribed in 14 CFR Part 133 approved by the FAA... activation devices, lighting equipment, oxygen cylinders, flotation devices, smoke grenades, flares, or... aircraft. (4) Hazardous materials are carried and used during dedicated air ambulance, fire fighting,...

  2. 49 CFR 175.9 - Special aircraft operations.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... aircraft. Operators must have all applicable requirements prescribed in 14 CFR Part 133 approved by the FAA... activation devices, lighting equipment, oxygen cylinders, flotation devices, smoke grenades, flares, or... aircraft. (4) Hazardous materials are carried and used during dedicated air ambulance, fire fighting,...

  3. Educating with Aircraft Models

    ERIC Educational Resources Information Center

    Steele, Hobie

    1976-01-01

    Described is utilization of aircraft models, model aircraft clubs, and model aircraft magazines to promote student interest in aerospace education. The addresses for clubs and magazines are included. (SL)

  4. Atmospheric Electrical Modeling in Support of the NASA F-106 Storm Hazards Project

    NASA Technical Reports Server (NTRS)

    Helsdon, John H., Jr.

    1988-01-01

    A recently developed storm electrification model (SEM) is used to investigate the operating environment of the F-106 airplane during the NASA Storm Hazards Project. The model is 2-D, time dependent and uses a bulkwater microphysical parameterization scheme. Electric charges and fields are included, and the model is fully coupled dynamically, microphysically and electrically. One flight showed that a high electric field was developed at the aircraft's operating altitude (28 kft) and that a strong electric field would also be found below 20 kft; however, this low-altitude, high-field region was associated with the presence of small hail, posing a hazard to the aircraft. An operational procedure to increase the frequency of low-altitude lightning strikes was suggested. To further the understanding of lightning within the cloud environment, a parameterization of the lightning process was included in the SEM. It accounted for the initiation, propagation, termination, and charge redistribution associated with an intracloud discharge. Finally, a randomized lightning propagation scheme was developed, and the effects of cloud particles on the initiation of lightning investigated.

  5. Determinants of Strike-Related Militancy: An Analysis of a University Faculty Strike.

    ERIC Educational Resources Information Center

    McClendon, John A.; Klaas, Brian

    1993-01-01

    During a 1990 Temple University faculty strike, three types of militancy (voting to strike, voting to defy injunction, picketing) had different determinants; for example, social support and union commitment related to riskier types. Other variables related to militancy included attitudes toward job, union, and militancy. (SK)

  6. Birds and Aircraft on Midway Islands, 1959-63 Investigations

    USGS Publications Warehouse

    Robbins, C.S.

    1966-01-01

    At Midway Naval Station, 1.100 miles west-northwest of Honolulu, military aircraft collide with flying albatrosses at the rate of about 300 to 400 per year. One aircraft out of every five that hits an albatross on takeoff either aborts (stops before it is airborne), or dumps fuel and returns for appraisal of damage. About 70,000 pairs of Laysan albatrosses and 7,000 pairs of blackfooted albatrosses nest at Midway in any given year. The population is declining. Two-thirds or more of the birds of breeding age nest each year. The minimum breeding age recorded is 5 years (each species), but many individuals do not nest until at least 7 years of age. Young birds begin to return to Midway at 3 years of age and are found more frequently as breeding age approaches. They come ashore more frequently in March and April (the high bird strike months) than in midwinter. Even in midwinter the number of 'walkers' (birds not on nests) may comprise more than 40 percent of the albatrosses present on Sand Island, Midway. Maximum longevity of the Laysan albatross is believed to exceed 40 years; 6 out of 99 birds banded as breeding adults (7+ years old) were still alive 24 years after banding. Control methods tested experimentally include disturbance, gunfire, other sounds, radar beams, smoke, odors, destruction of nests, eggs, chicks, and adults, moving of birds, eggs, and chicks, erection of obstacles to flight, and habitat management. Habitat management (leveling and hardsurfacing of shoulders of runways) has been the most effective. Albatrosses were counted over the runways at 10 locations in 1957, 1958, and 1960 to determine the effects of wind direction, wind speed, and topography on the numbers of flying birds. Birds were most concentrated in areas where rising air currents were created as winds blew against dunes or tall trees. Soaring and strike rate both increased with greater wind speeds. There was a highly significant correlation between strike frequency and wind direction

  7. Reproductive Hazards

    MedlinePlus

    ... such as lead and mercury Chemicals such as pesticides Cigarettes Some viruses Alcohol For men, a reproductive hazard can affect the sperm. For a woman, a reproductive hazard can cause different effects during pregnancy, depending on when she is exposed. ...

  8. 49 CFR 175.3 - Unacceptable hazardous materials shipments.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 49 Transportation 2 2014-10-01 2014-10-01 false Unacceptable hazardous materials shipments. 175.3 Section 175.3 Transportation Other Regulations Relating to Transportation PIPELINE AND HAZARDOUS MATERIALS SAFETY ADMINISTRATION, DEPARTMENT OF TRANSPORTATION HAZARDOUS MATERIALS REGULATIONS CARRIAGE BY AIRCRAFT General Information and Regulations...

  9. Striking Down the Communications Decency Act.

    ERIC Educational Resources Information Center

    Russo, Charles J.

    1998-01-01

    The Supreme Court's decision in "Reno," striking down major portions of the Communications Decency Act of 1996, pits the need to protect children from inappropriate material against the need to maintain free Internet access by adults. Highlights major points in the holding and discusses the meaning of "Reno" for educators. (MLF)

  10. The Chicago Teachers Strike and Its Public

    ERIC Educational Resources Information Center

    Shuffelton, Amy B.

    2014-01-01

    This article considers the 2012 Chicago Teachers Strike in light of John Dewey's "The Public and Its Problems." It engages Dewey's conceptualization of practical reason to challenge the educational reform movement's commitment to technocratic decision-making.

  11. Protecting Your Park When Lightning Strikes.

    ERIC Educational Resources Information Center

    Frydenlund, Marvin M.

    1987-01-01

    A formula for assessing specific risk of lightning strikes is provided. Recent legal cases are used to illustrate potential liability. Six actions park managers can take to minimize danger from lightning are presented, and commonsense rules which should be publicly posted are listed. (MT)

  12. STS-135 Launch Pad Lightning Strike

    NASA Video Gallery

    A pair of lightning strikes occurred near launch pad 39-A at NASA's Kennedy Space Center at 12:31 p.m. and 12:40 p.m. EDT on July 7. The first struck the water tower 515 feet from the pad and the s...

  13. Television News and the Miners' Strike.

    ERIC Educational Resources Information Center

    Cumberbatch, Guy; And Others

    A content analysis was performed on all of the BBC (British Broadcasting Corporation) Nine O'Clock News and ITV (Independent Television) News at Ten programs that were broadcast during Britain's year-long miners' strike--March 1984-March 1985--and a four-month sample of Channel 4 news to examine how television news covered a protracted story of…

  14. What to Expect During a Teachers' Strike.

    ERIC Educational Resources Information Center

    Long, Jerri

    1987-01-01

    This two-page table charts the range of union activities, their adversarial intent, and possible administrative counterstrategies during a typical teacher strike. Twenty-four activities are covered, from peaceful demonstrations (like picketing), marches, and candlelight vigils, to harassments like nails in tires and telephone threats. (MLH)

  15. Endgame Is Eyed in Chicago Strike

    ERIC Educational Resources Information Center

    Sawchuk, Stephen

    2012-01-01

    A strike last week by some 29,000 teachers in Chicago pushed long-simmering tensions over deeply divisive school improvement ideas--including changes in teacher evaluation and the takeover or closure of underperforming schools--into the national spotlight. A framework for a tentative agreement emerged last Friday, and the union's house of…

  16. Registration of 'FirstStrike' Slender Wheatgrass

    Technology Transfer Automated Retrieval System (TEKTRAN)

    'FirstStrike' slender wheatgrass [Elymus trachycaulus (Link) Gould ex Shinners] was developed by a research team at the USDA-ARS-Forage and Range Research Laboratory and collaborators at the United States Army - Engineer Research and Development Center and was released on 16 October 2006. FirstStri...

  17. Teaching Striking/Fielding Concepts in Cricket

    ERIC Educational Resources Information Center

    Turner, Adrian P.

    2004-01-01

    This article presents activities for developing striking/fielding concepts in modified cricket games. Though not as familiar to American children, cricket is emerging as the second (to soccer) most popular game in the world. The novelty of the skills provides an appropriate learning challenge for all students while reinforcing concepts and…

  18. Lightning Strike Induced Damage Mechanisms of Carbon Fiber Composites

    NASA Astrophysics Data System (ADS)

    Kawakami, Hirohide

    Composite materials have a wide application in aerospace, automotive, and other transportation industries, because of the superior structural and weight performances. Since carbon fiber reinforced polymer composites possess a much lower electrical conductivity as compared to traditional metallic materials utilized for aircraft structures, serious concern about damage resistance/tolerance against lightning has been rising. Main task of this study is to clarify the lightning damage mechanism of carbon fiber reinforced epoxy polymer composites to help further development of lightning strike protection. The research on lightning damage to carbon fiber reinforced polymer composites is quite challenging, and there has been little study available until now. In order to tackle this issue, building block approach was employed. The research was started with the development of supporting technologies such as a current impulse generator to simulate a lightning strike in a laboratory. Then, fundamental electrical properties and fracture behavior of CFRPs exposed to high and low level current impulse were investigated using simple coupon specimens, followed by extensive parametric investigations in terms of different prepreg materials frequently used in aerospace industry, various stacking sequences, different lightning intensity, and lightning current waveforms. It revealed that the thermal resistance capability of polymer matrix was one of the most influential parameters on lightning damage resistance of CFRPs. Based on the experimental findings, the semi-empirical analysis model for predicting the extent of lightning damage was established. The model was fitted through experimental data to determine empirical parameters and, then, showed a good capability to provide reliable predictions for other test conditions and materials. Finally, structural element level lightning tests were performed to explore more practical situations. Specifically, filled-hole CFRP plates and patch

  19. 49 CFR 173.172 - Aircraft hydraulic power unit fuel tank.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 49 Transportation 2 2012-10-01 2012-10-01 false Aircraft hydraulic power unit fuel tank. 173.172 Section 173.172 Transportation Other Regulations Relating to Transportation PIPELINE AND HAZARDOUS... Class 1 and Class 7 § 173.172 Aircraft hydraulic power unit fuel tank. Aircraft hydraulic power...

  20. 49 CFR 173.172 - Aircraft hydraulic power unit fuel tank.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 49 Transportation 2 2010-10-01 2010-10-01 false Aircraft hydraulic power unit fuel tank. 173.172 Section 173.172 Transportation Other Regulations Relating to Transportation PIPELINE AND HAZARDOUS... Class 1 and Class 7 § 173.172 Aircraft hydraulic power unit fuel tank. Aircraft hydraulic power...

  1. Affordable MMW aircraft collision avoidance system

    NASA Astrophysics Data System (ADS)

    Almsted, Larry D.; Becker, Robert C.; Zelenka, Richard E.

    1997-06-01

    Collision avoidance is of concern to all aircraft, requiring the detection and identification of hazardous terrain or obstacles in sufficient time for clearance maneuvers. The collision avoidance requirement is even more demanding for helicopters, as their unique capabilities result in extensive operations at low-altitude, near to terrain and other hazardous obstacles. TO augment the pilot's visual collision avoidance abilities, some aircraft are equipped with 'enhanced-vision' systems or terrain collision warning systems. Enhanced-vision systems are typically very large and costly systems that are not very covert and are also difficult to install in a helicopter. The display is typically raw images from infrared or radar sensors, and can require a high degree of pilot interpretation and attention. Terrain collision warning system that rely on stored terrain maps are often of low resolution and accuracy and do not represent hazards to the aircraft placed after map sampling. Such hazards could include aircraft parked on runway, man- made towers or buildings and hills. In this paper, a low cost dual-function scanning pencil-beam, millimeter-wave radar forward sensor is used to determine whether an aircraft's flight path is clear of obstructions. Due to the limited space and weight budget in helicopters, the system is a dual function system that is substituted in place of the existing radar altimeter. The system combines a 35 GHz forward looking obstacle avoidance radar and a 4.3 GHz radar altimeter. The forward looking 35 GHz 3D radar's returns are used to construct a terrain and obstruction database surrounding an aircraft, which is presented to the pilot as a synthetic perspective display. The 35 GHz forward looking radar and the associated display was evaluated in a joint NASA Honeywell flight test program in 1996. The tests were conducted on a NASA/Army test helicopter. The test program clearly demonstrated the systems potential usefulness for collision avoidance.

  2. Aircraft Electric Secondary Power

    NASA Technical Reports Server (NTRS)

    1983-01-01

    Technologies resulted to aircraft power systems and aircraft in which all secondary power is supplied electrically are discussed. A high-voltage dc power generating system for fighter aircraft, permanent magnet motors and generators for aircraft, lightweight transformers, and the installation of electric generators on turbine engines are among the topics discussed.

  3. World commercial aircraft accidents

    SciTech Connect

    Kimura, C.Y.

    1993-01-01

    This report is a compilation of all accidents world-wide involving aircraft in commercial service which resulted in the loss of the airframe or one or more fatality, or both. This information has been gathered in order to present a complete inventory of commercial aircraft accidents. Events involving military action, sabotage, terrorist bombings, hijackings, suicides, and industrial ground accidents are included within this list. Included are: accidents involving world commercial jet aircraft, world commercial turboprop aircraft, world commercial pistonprop aircraft with four or more engines and world commercial pistonprop aircraft with two or three engines from 1946 to 1992. Each accident is presented with information in the following categories: date of the accident, airline and its flight numbers, type of flight, type of aircraft, aircraft registration number, construction number/manufacturers serial number, aircraft damage, accident flight phase, accident location, number of fatalities, number of occupants, cause, remarks, or description (brief) of the accident, and finally references used. The sixth chapter presents a summary of the world commercial aircraft accidents by major aircraft class (e.g. jet, turboprop, and pistonprop) and by flight phase. The seventh chapter presents several special studies including a list of world commercial aircraft accidents for all aircraft types with 100 or more fatalities in order of decreasing number of fatalities, a list of collision accidents involving commercial aircrafts, and a list of world commercial aircraft accidents for all aircraft types involving military action, sabotage, terrorist bombings, and hijackings.

  4. Costs of strikes between vulnerable missile forces

    SciTech Connect

    Canavan, G.H.

    1997-02-01

    This note derives the first and second strike magnitudes and costs for strikes between vulnerable missile forces with multiple warheads. The extension to mixes with invulnerable missiles is performed in a companion note. Stability increases as the number of weapons per missile is reduced. The optimal allocation of weapons between missiles and value is significant in predicting the stability impact of the reduction of the number of weapons per missile at large numbers of missiles, less significant in reducing the number of missiles for fixed weapons per missile. At low numbers of missiles, the stability indices for singlet and triplet configurations are comparable, as are the number of weapons each would deliver on value targets.

  5. Central Hyperadrenergic State After Lightning Strike

    PubMed Central

    Parsaik, Ajay K.; Ahlskog, J. Eric; Singer, Wolfgang; Gelfman, Russell; Sheldon, Seth H.; Seime, Richard J.; Craft, Jennifer M.; Staab, Jeffrey P.; Kantor, Birgit; Low, Phillip A.

    2013-01-01

    Objective To describe and review autonomic complications of lightning strike. Methods Case report and laboratory data including autonomic function tests in a subject who was struck by lightning. Results A 24-year-old man was struck by lightning. Following that, he developed dysautonomia, with persistent inappropriate sinus tachycardia and autonomic storms, as well as posttraumatic stress disorder (PTSD) and functional neurologic problems. Interpretation The combination of persistent sinus tachycardia and episodic exacerbations associated with hypertension, diaphoresis, and agitation were highly suggestive of a central hyperadrenergic state with superimposed autonomic storms. Whether the additional PTSD and functional neurologic deficits were due to a direct effect of the lightning strike on the CNS or a secondary response is open to speculation. PMID:23761114

  6. The California Hazards Institute

    NASA Astrophysics Data System (ADS)

    Rundle, J. B.; Kellogg, L. H.; Turcotte, D. L.

    2006-12-01

    California's abundant resources are linked with its natural hazards. Earthquakes, landslides, wildfires, floods, tsunamis, volcanic eruptions, severe storms, fires, and droughts afflict the state regularly. These events have the potential to become great disasters, like the San Francisco earthquake and fire of 1906, that overwhelm the capacity of society to respond. At such times, the fabric of civic life is frayed, political leadership is tested, economic losses can dwarf available resources, and full recovery can take decades. A patchwork of Federal, state and local programs are in place to address individual hazards, but California lacks effective coordination to forecast, prevent, prepare for, mitigate, respond to, and recover from, the harmful effects of natural disasters. Moreover, we do not know enough about the frequency, size, time, or locations where they may strike, nor about how the natural environment and man-made structures would respond. As California's population grows and becomes more interdependent, even moderate events have the potential to trigger catastrophes. Natural hazards need not become natural disasters if they are addressed proactively and effectively, rather than reactively. The University of California, with 10 campuses distributed across the state, has world-class faculty and students engaged in research and education in all fields of direct relevance to hazards. For that reason, the UC can become a world leader in anticipating and managing natural hazards in order to prevent loss of life and property and degradation of environmental quality. The University of California, Office of the President, has therefore established a new system-wide Multicampus Research Project, the California Hazards Institute (CHI), as a mechanism to research innovative, effective solutions for California. The CHI will build on the rich intellectual capital and expertise of the Golden State to provide the best available science, knowledge and tools for

  7. Systems tunnel linear shaped charge lightning strike

    NASA Technical Reports Server (NTRS)

    Cook, M.

    1989-01-01

    Simulated lightning strike testing of the systems tunnel linear shaped charge (LSC) was performed at the Thiokol Lightning Test Complex in Wendover, Utah, on 23 Jun. 1989. The test article consisted of a 160-in. section of the LSC enclosed within a section of the systems tunnel. The systems tunnel was bonded to a section of a solid rocket motor case. All test article components were full scale. The systems tunnel cover of the test article was subjected to three discharges (each discharge was over a different grounding strap) from the high-current generator. The LSC did not detonate. All three grounding straps debonded and violently struck the LSC through the openings in the systems tunnel floor plates. The LSC copper surface was discolored around the areas of grounding strap impact, and arcing occurred at the LSC clamps and LSC ends. This test verified that the present flight configuration of the redesigned solid rocket motor systems tunnel, when subjected to simulated lightning strikes with peak current levels within 71 percent of the worst-case lightning strike condition of NSTS-07636, is adequate to prevent LSC ignition. It is therefore recommended that the design remain unchanged.

  8. Preemptive Striking in Individual and Group Conflict.

    PubMed

    Mifune, Nobuhiro; Hizen, Yoichi; Kamijo, Yoshio; Okano, Yoshitaka

    2016-01-01

    In this study, we conducted a laboratory experiment to assess preemptive striking by and towards individuals or groups. In the framework of a preemptive strike game, we set the following four conditions: one person faced another person, one person faced a three-person group, a three-person group faced an individual, and a three-person group faced another three-person group. Previous studies have revealed that greed is activated when participants belong to a group, while fear is activated when participants interact with a group, and further, that attacking behaviors in the preemptive strike game are driven by fear. These observations led to a hypothesis that high attack rates would be realized when participants interact with a group, regardless of whether the participants make decisions as individuals or a group. The results of our experiment, however, rejected this hypothesis. Among the four conditions, the attack rate was highest when a three-person group faced an individual. As possible reasons for our observation, we discuss the potential threat stemming from the imbalance in the effectiveness of attack between individuals and groups, and the (incorrect) belief by groups that single individuals would be more likely to attack out of fear. PMID:27148871

  9. Preemptive Striking in Individual and Group Conflict

    PubMed Central

    Mifune, Nobuhiro; Hizen, Yoichi; Kamijo, Yoshio; Okano, Yoshitaka

    2016-01-01

    In this study, we conducted a laboratory experiment to assess preemptive striking by and towards individuals or groups. In the framework of a preemptive strike game, we set the following four conditions: one person faced another person, one person faced a three-person group, a three-person group faced an individual, and a three-person group faced another three-person group. Previous studies have revealed that greed is activated when participants belong to a group, while fear is activated when participants interact with a group, and further, that attacking behaviors in the preemptive strike game are driven by fear. These observations led to a hypothesis that high attack rates would be realized when participants interact with a group, regardless of whether the participants make decisions as individuals or a group. The results of our experiment, however, rejected this hypothesis. Among the four conditions, the attack rate was highest when a three-person group faced an individual. As possible reasons for our observation, we discuss the potential threat stemming from the imbalance in the effectiveness of attack between individuals and groups, and the (incorrect) belief by groups that single individuals would be more likely to attack out of fear. PMID:27148871

  10. Resistance, mobilization and militancy: nurses on strike.

    PubMed

    Briskin, Linda

    2012-12-01

    Drawing on nurses' strikes in many countries, this paper explores nurse militancy with reference to professionalism and the commitment to service; patriarchal practices and gendered subordination; and proletarianization and the confrontation with healthcare restructuring. These deeply entangled trajectories have had a significant impact on the work, consciousness and militancy of nurses and have shaped occupation-specific forms of resistance. They have produced a pattern of overlapping solidarities--occupational solidarity, gendered alliances and coalitions around healthcare restructuring--which have supported, indeed promoted, militancy among nurses, despite the multiple forces arrayed against them. The professional commitments of nurses to the provision of care have confronted healthcare restructuring, nursing shortages, intensification of work, precarious employment and gendered hierarchies with a militant discourse around the public interest, and a reconstitution and reclamation of 'caring', what I call the politicisation of caring. In fact, nurses' dedication to caring work in the late twentieth and early twenty-first centuries may encourage rather than dissuade them from going on strike. This paper uses a trans-disciplinary methodology, qualitative material in the form of strike narratives constructed from newspaper archives, and references to the popular and scholarly literature on nursing militancy. PMID:22059465

  11. Natural Hazards

    NASA Astrophysics Data System (ADS)

    Bryant, Edward

    2005-02-01

    This updated new edition presents a comprehensive, inter-disciplinary analysis of the complete range of natural hazards. Edward Bryant describes and explains how hazards occur, examines prediction methods, considers recent and historical hazard events and explores the social impact of such disasters. Supported by over 180 maps, diagrams and photographs, this standard text is an invaluable guide for students and professionals in the field. First Edition Hb (1991): 0-521-37295-X First Edition Pb (1991): 0-521-37889-3

  12. Survival analysis of aging aircraft

    NASA Astrophysics Data System (ADS)

    Benavides, Samuel

    work demonstrates the development of a probabilistic corrosion failure model using survival analysis methods and techniques. Using a parsimonious approach, the coefficients of a Cox proportional hazards model were derived from a set of environmental, geographical and operational predictor variables. To determine if the variables satisfied the proportional hazard assumption, numerous statistical tests were performed---such as the equivalence tests of the log rank, Wilcoxon, Peto-Peto and Fleming-Harrington---and graphical plots generated such as observed-versus-expected plots and log(-log) survival curves. Finally, in a paradigm enhancement to current design methodologies, this dissertation place sets survival analysis modeling in the context of an emerging holistic structural integrity philosophy. While traditional aircraft design and life prediction methodologies consider only the cyclic fatigue domain without consideration to the environmental or unique operating spectrum that aircraft may fly in, a holistic approach considers the cradle-to-grave driving forces in the life of a component, such as corrosion assisted crack nucleation in a material. This dissertation, which uses real-world failure data obtained from structural aircraft components, is poised to narrow the cradle-to-grave loop and provide holistic feedback in the understanding of aircraft structural system failures.

  13. Evaluation of Equipment Vulnerability and Potential Shock Hazards. [carbon fibers

    NASA Technical Reports Server (NTRS)

    Taback, I.

    1980-01-01

    The vulnerability of electric equipment to carbon fibers released from aircraft accidents is investigated and the parameters affecting vulnerability are discussed. The shock hazard for a hypothetical set of accidents is computed.

  14. Volcanic hazards and aviation safety

    USGS Publications Warehouse

    Casadevall, Thomas J.; Thompson, Theodore B.; Ewert, John W.

    1996-01-01

    An aeronautical chart was developed to determine the relative proximity of volcanoes or ash clouds to the airports and flight corridors that may be affected by volcanic debris. The map aims to inform and increase awareness about the close spatial relationship between volcanoes and aviation operations. It shows the locations of the active volcanoes together with selected aeronautical navigation aids and great-circle routes. The map mitigates the threat that volcanic hazards pose to aircraft and improves aviation safety.

  15. Coping with volcanic hazards; a global perspective

    USGS Publications Warehouse

    Tilling, R.I.

    1990-01-01

    Compared to some other natural hazards-such as floods, storms, earthquakes, landslides- volcanic hazards strike infrequently. However, in populated areas , even very small eruptions can wreak havoc and cause widespread devastation. For example, the 13 November 1985 eruption of Nevado del Ruiz in Colombia ejected only about 3 percent of the volume of ash produced during the 18 May 1980 eruption of Mount St. Helens. Yet, the mudflows triggered by this tiny eruption killed more than 25,000 people.

  16. Rapid measurement of emissions from military aircraft turbine engines by downstream extractive sampling of aircraft on the ground: Results for C-130 and F-15 aircraft

    NASA Astrophysics Data System (ADS)

    Spicer, Chester W.; Holdren, Michael W.; Cowen, Kenneth A.; Joseph, Darrell W.; Satola, Jan; Goodwin, Bradley; Mayfield, Howard; Laskin, Alexander; Lizabeth Alexander, M.; Ortega, John V.; Newburn, Matthew; Kagann, Robert; Hashmonay, Ram

    Aircraft emissions affect air quality on scales from local to global. More than 20% of the jet fuel used in the U.S. is consumed by military aircraft, and emissions from this source are facing increasingly stringent environmental regulations, so improved methods for quickly and accurately determining emissions from existing and new engines are needed. This paper reports results of a study to advance the methods used for detailed characterization of military aircraft emissions, and provides emission factors for two aircraft: the F-15 fighter and the C-130 cargo plane. The measurements involved outdoor ground-level sampling downstream behind operational military aircraft. This permits rapid change-out of the aircraft so that engines can be tested quickly on operational aircraft. Measurements were made at throttle settings from idle to afterburner using a simple extractive probe in the dilute exhaust. Emission factors determined using this approach agree very well with those from the traditional method of extractive sampling at the exhaust exit. Emission factors are reported for CO 2, CO, NO, NO x, and more than 60 hazardous and/or reactive organic gases. Particle size, mass and composition also were measured and are being reported separately. Comparison of the emissions of nine hazardous air pollutants from these two engines with emissions from nine other aircraft engines is discussed.

  17. Hazardous materials

    MedlinePlus

    ... people how to work with hazardous materials and waste. There are many different kinds of hazardous materials, including: Chemicals, like some that are used for cleaning Drugs, like chemotherapy to treat cancer Radioactive material that is used for x-rays or ...

  18. Acute transient hemiparesis induced by lightning strike.

    PubMed

    Rahmani, Seyed Hesam; Faridaalaee, Gholamreza; Jahangard, Samira

    2015-07-01

    According to data from the National Oceanic and Atmospheric Administration,in the years from 1959 to 1994, lightning was responsible for more than 3000 deaths and nearly 10,000 casualties. The most important characteristic features of lightning injuries are multisystem involvement and widely variable severity. Lightning strikes are primarily a neurologic injury that affects all 3 components of the nervous system: central, autonomic,and peripheral. Neurologic complications of lightning strikes vary from transient benign symptoms to permanent disability. Many patients experience a temporary paralysis called keraunoparalysis. Here we reported a 22-year-old mountaineer man with complaining of left sided hemiparesis after being hit by a lightning strike in the mountain 3 hours ago. There was no loss of consciousness at hitting time. On arrival the patient was alert, awake and hemodynamically stable. In neurologic examination cranial nerves were intact, left sided upper and lower extremity muscle force was I/V with a combination of complete sensory loss, and right-sided muscle force and sensory examination were normal. There is not any evidence of significant vascular impairment in the affected extremities. Brain MRI and CT scan and cervical MRI were normal. During 2 days of admission, with intravenous hydration, heparin 5000 unit SC q12hr and physical therapy of the affected limbs, motor and sensory function improved and was normal except mild paresthesia. He was discharged 1 day later for outpatient follow up while vitamin B1 100mg orally was prescribed.Paresthesia improved after 3 days without further sequels. PMID:25650360

  19. Lightning strike-induced brachial plexopathy

    PubMed Central

    Bhargava, Amita N.; Kasundra, Gaurav M.; Khichar, Subhakaran; Bhushan, Bharat S. K.

    2014-01-01

    We describe a patient who presented with a history of lightning strike injury. Following the injury, he sustained acute right upper limb weakness with pain. Clinically, the lesion was located to the upper and middle trunk of the right brachial plexus, and the same confirmed with electrophysiological studies. Nerve damage due to lightning injuries is considered very rare, and a plexus damage has been described infrequently, if ever. Thus, the proposed hypothesis that lightning rarely causes neuropathy, as against high-voltage electric current, due to its shorter duration of exposure not causing severe burns which lead to nerve damage, needs to be reconsidered. PMID:25288846

  20. Suppression of strike-slip fault systems

    NASA Astrophysics Data System (ADS)

    Curren, I. S.

    2012-12-01

    In orogens elongated parallel to a great circle about the Euler pole for the two bounding plates, theory requires simple-shear deformation in the form of distributed deformation or velocity discontinuities across strike-slip faults. This type of deformation, however, does not develop at all plate boundaries requiring toroidal motion. Using the global plate boundary model, PB2002 [Bird, 2003], as the basis for identifying areas where expected simple-shear deformation is absent or underdeveloped, it was also possible to identify two potential causes for this behavior: (1) the presence of extensive fracturing at right angles to the shear plane and (2) regional cover of flood basalts or andesites with columnar joints. To test this hypothesis, a new plane-stress finite-strain model was developed to study the effects of such pre-existing structures on the development of simple shear in a clay cake. A homogenous kaolinite-water mixture was poured into a deforming parallelogram box and partially dried to allow for brittle and plastic deformation at and below the surface of the clay, respectively. This was floated on a dense fluid foundation, effectively removing basal friction, and driven by a motor in a sinistral direction from the sides of the box. Control experiments produced classic Riedel model fault assemblages and discrete, through-going primary deformation zones (PDZs); experiments with pre-existing structures developed the same, though subdued and distributed, fault assemblages but did not develop through-going PDZs. Although formation of strike-slip faults was underdeveloped at the surface in clay with pre-existing structures, offset within the clay cake (measured, with respect to a fixed point, by markers on the clay surface) as a fraction of total offset of the box was consistently larger than that of the control experiments. This suggests that while the extent of surface faulting was lessened in clay with pre-existing structures, slip was still occurring at

  1. Propulsion controlled aircraft computer

    NASA Technical Reports Server (NTRS)

    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.

  2. Neurological complications of prolonged hunger strike.

    PubMed

    Başoğlu, M; Yetimalar, Y; Gürgör, N; Büyükçatalbaş, S; Kurt, T; Seçil, Y; Yeniocak, A

    2006-10-01

    We investigated neurological findings in 41 prisoners (mean age: 28.6) who participated in a hunger strike between 2000 and 2002. All cases were evaluated using neuropsychological, neuroradiological, and electrophysiological methods. The total duration of fasting ranged from 130 to 324 days (mean 199 days). All cases had 200-600 mg/day thiamine orally for 60-294 days (mean 156) during the hunger strike, and had neurological findings consistent with Wernicke-Korsakoff syndrome. All 41 patients exhibited altered consciousness which lasted from 3 to 31 days. All patients also presented gaze-evoked horizontal nystagmus and truncal ataxia. Paralysis of lateral rectus muscles was found in 14. Amnesia was apparent in all cases. Abnormal nerve conduction study parameters were not found in the patient group, but the amplitude of compound muscle action potential of the median and fibular nerves and sensory nerve action potential amplitude of the sural nerve were lower than the control group, and distal motor latency of the posterior tibial nerve was significantly prolonged as compared with the control group. The latency of visual evoked potential was prolonged in 22 cases. Somatosensory evoked potential (P37) was prolonged but not statistically significant. Our most significant finding was that the effect of hunger was more prominent on the central nervous system than on the neuromuscular system, despite the fact that all patients were taking thiamine. In our opinion, partial recovery of neurological, and neurocognitive signs in prolonged hunger could be a result of permanent neurological injury. PMID:16987161

  3. Worker responses to workplace hazards.

    PubMed

    Robinson, J C

    1987-01-01

    Recent policy initiatives in occupational safety and health have emphasized strategies that provide workers with information about workplace exposures. It is not clear, however, what effect this new information has had or will have on worker self-help initiatives. This paper analyzes individual and collective worker responses to information on job hazards using five sources of data on workers and industries in the United States. Levels of expressed dissatisfaction, discharges for cause, and strike frequencies are found to be significantly higher in hazardous jobs than in safe jobs. Individual quit strategies are not consistently found to be associated with higher hazard levels. These findings have potentially important implications for the design of future information-oriented health and safety policies. PMID:3429802

  4. Foot-strike pattern and performance in a marathon

    PubMed Central

    Kasmer, Mark E.; Liu, Xue-cheng; Roberts, Kyle G.; Valadao, Jason M.

    2016-01-01

    Purpose To: 1) determine prevalence of heel-strike in a mid-size city marathon, 2) determine if there is an association between foot-strike classification and race performance, and 3) determine if there is an association between foot-strike classification and gender. Methods Foot-strike classification (fore-foot strike, mid-foot strike, heel strike, or split-strike), gender, and rank (position in race) were recorded at the 8.1 kilometer (km) mark for 2,112 runners at the 2011 Milwaukee Lakefront Marathon. Results 1,991 runners were classified by foot-strike pattern, revealing a heel-strike prevalence of 93.67% (n=1,865). A significant difference between foot-strike classification and performance was found using a Kruskal-Wallis test (p < 0.0001), with more elite performers being less likely to heel-strike. No significant difference between foot-strike classification and gender was found using a Fisher’s exact test. Additionally, subgroup analysis of the 126 non-heel strikers found no significant difference between shoe wear and performance using a Kruskal-Wallis test. Conclusions The high prevalence of heel-striking observed in this study reflects the foot-strike pattern of the majority of mid- to long-distance runners and more importantly, may predict their injury profile based on the biomechanics of a heel strike running pattern. This knowledge can aid the clinician in the appropriate diagnosis, management, and training modifications of the injured runner. PMID:23006790

  5. 20 CFR 345.402 - Strikes or work stoppages.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 20 Employees' Benefits 1 2012-04-01 2012-04-01 false Strikes or work stoppages. 345.402 Section... INSURANCE ACT EMPLOYERS' CONTRIBUTIONS AND CONTRIBUTION REPORTS Benefit Charging § 345.402 Strikes or work stoppages. If benefits are payable to an employee for days of unemployment resulting from a strike or...

  6. 20 CFR 345.402 - Strikes or work stoppages.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... INSURANCE ACT EMPLOYERS' CONTRIBUTIONS AND CONTRIBUTION REPORTS Benefit Charging § 345.402 Strikes or work stoppages. If benefits are payable to an employee for days of unemployment resulting from a strike or work... 20 Employees' Benefits 1 2010-04-01 2010-04-01 false Strikes or work stoppages. 345.402...

  7. 20 CFR 345.402 - Strikes or work stoppages.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 20 Employees' Benefits 1 2011-04-01 2011-04-01 false Strikes or work stoppages. 345.402 Section... INSURANCE ACT EMPLOYERS' CONTRIBUTIONS AND CONTRIBUTION REPORTS Benefit Charging § 345.402 Strikes or work stoppages. If benefits are payable to an employee for days of unemployment resulting from a strike or...

  8. 20 CFR 345.402 - Strikes or work stoppages.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 20 Employees' Benefits 1 2014-04-01 2012-04-01 true Strikes or work stoppages. 345.402 Section 345... INSURANCE ACT EMPLOYERS' CONTRIBUTIONS AND CONTRIBUTION REPORTS Benefit Charging § 345.402 Strikes or work stoppages. If benefits are payable to an employee for days of unemployment resulting from a strike or...

  9. 20 CFR 345.402 - Strikes or work stoppages.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 20 Employees' Benefits 1 2013-04-01 2012-04-01 true Strikes or work stoppages. 345.402 Section 345... INSURANCE ACT EMPLOYERS' CONTRIBUTIONS AND CONTRIBUTION REPORTS Benefit Charging § 345.402 Strikes or work stoppages. If benefits are payable to an employee for days of unemployment resulting from a strike or...

  10. Hazardous materials

    MedlinePlus

    ... should be in a room with good airflow Work Safely If you find a spill, treat it like ... Hazard communication; Material Safety Data Sheet; MSDS References Occupational Safety and Health Administration. Healthcare. Available at: www.osha. ...

  11. Coastal Hazards.

    ERIC Educational Resources Information Center

    Vandas, Steve

    1998-01-01

    Focuses on hurricanes and tsunamis and uses these topics to address other parts of the science curriculum. In addition to a discussion on beach erosion, a poster is provided that depicts these natural hazards that threaten coastlines. (DDR)

  12. Hazardous Waste

    MedlinePlus

    ... wastes come from products in our homes. Our garbage can include such hazardous wastes as old batteries, ... drain, flush them, or put them in the garbage. See if you can donate or recycle. Many ...

  13. Reproductive Hazards

    MedlinePlus

    ... and female reproductive systems play a role in pregnancy. Problems with these systems can affect fertility and ... a reproductive hazard can cause different effects during pregnancy, depending on when she is exposed. During the ...

  14. Aircraft noise problems

    NASA Astrophysics Data System (ADS)

    1981-01-01

    The problems related to aircraft noise were studied. Physical origin (sound), human reaction (noise), quantization of noise and sound sources of aircraft noise are discussed. Noise abatement at the source, technical, fleet-political and air traffic measures are explained. The measurements and future developments are also discussed. The position of Lufthansa as regards aircraft noise problems is depicted.

  15. Unmanned aircraft systems

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Unmanned platforms have become increasingly more common in recent years for acquiring remotely sensed data. These aircraft are referred to as Unmanned Airborne Vehicles (UAV), Remotely Piloted Aircraft (RPA), Remotely Piloted Vehicles (RPV), or Unmanned Aircraft Systems (UAS), the official term used...

  16. Using avian radar to examine relationships among avian activity, bird strikes, and meteorological factors

    USGS Publications Warehouse

    Coates, Peter S.; Casazza, Michael L.; Halstead, Brian J.; Fleskes, Joseph P.; Laughlin, James A.

    2011-01-01

    Radar systems designed to detect avian activity at airfields are useful in understanding factors that influence the risk of bird and aircraft collisions (bird strikes). We used an avian radar system to measure avian activity at Beale Air Force Base, California, USA, during 2008 and 2009. We conducted a 2-part analysis to examine relationships among avian activity, bird strikes, and meteorological and time-dependent factors. We found that avian activity around the airfield was greater at times when bird strikes occurred than on average using a permutation resampling technique. Second, we developed generalized linear mixed models of an avian activity index (AAI). Variation in AAI was first explained by seasons that were based on average migration dates of birds at the study area. We then modeled AAI by those seasons to further explain variation by meteorological factors and daily light levels within a 24-hour period. In general, avian activity increased with decreased temperature, wind, visibility, precipitation, and increased humidity and cloud cover. These effects differed by season. For example, during the spring bird migration period, most avian activity occurred before sunrise at twilight hours on clear days with low winds, whereas during fall migration, substantial activity occurred after sunrise, and birds generally were more active at lower temperatures. We report parameter estimates (i.e., constants and coefficients) averaged across models and a relatively simple calculation for safety officers and wildlife managers to predict AAI and the relative risk of bird strike based on time, date, and meteorological values. We validated model predictability and assessed model fit. These analyses will be useful for general inference of avian activity and risk assessment efforts. Further investigation and ongoing data collection will refine these inference models and improve our understanding of factors that influence avian activity, which is necessary to inform

  17. A NASA study of the impact of technology on future carrier based tactical aircraft - Overview

    NASA Technical Reports Server (NTRS)

    Wilson, S. B., III

    1992-01-01

    This paper examines the impact of technology on future carrier based tactical aircraft. The results were used in the Center for Naval Analysis Future Carrier Study. The NASA Team designed three classes of aircraft ('Fighter', 'Attack', and 'Multimission') with two different technology levels. The Multimission aircraft were further analyzed by examining the penalty on the aircraft for both catapult launch/arrested landing recovery (Cat/trap) and short take-off/vertical landing (STOVL). The study showed the so-called STOVL penalty was reduced by engine technology and the next generation Strike Fighter will pay more penalty for Cat/trap than for STOVL capability.

  18. Ability of photovoltaic modules to withstand lightning strikes

    NASA Astrophysics Data System (ADS)

    Felder, B.; Robb, J. D.

    The ability of glass superstrate and metal/plastic substrate modules to withstand lightning strikes was examined. Each of three different types of modules were exposed to four nearby and one direct strike of high voltage, long arc simulated lightning, and to one direct strike of high current, long duration lightning. Visual and electrical examination demonstrated that the high voltage strikes produced no electrical damage to the glass superstrate modules and little to the plastic substrate module. The high current, long duration strike resulted in varying degrees of physical damage to all modules but little or no loss in electrical performance.

  19. Aircraft landing gear systems

    NASA Technical Reports Server (NTRS)

    Tanner, John A. (Editor)

    1990-01-01

    Topics presented include the laboratory simulation of landing gear pitch-plane dynamics, a summary of recent aircraft/ground vehicle friction measurement tests, some recent aircraft tire thermal studies, and an evaluation of critical speeds in high-speed aircraft. Also presented are a review of NASA antiskid braking research, titanium matrix composite landing gear development, the current methods and perspective of aircraft flotation analysis, the flow rate and trajectory of water spray produced by an aircraft tire, and spin-up studies of the Space Shuttle Orbiter main gear tire.

  20. NASA technical advances in aircraft occupant safety. [clear air turbulence detectors, fire resistant materials, and crashworthiness

    NASA Technical Reports Server (NTRS)

    Enders, J. H.

    1978-01-01

    NASA's aviation safety technology program examines specific safety problems associated with atmospheric hazards, crash-fire survival, control of aircraft on runways, human factors, terminal area operations hazards, and accident factors simulation. While aircraft occupants are ultimately affected by any of these hazards, their well-being is immediately impacted by three specific events: unexpected turbulence encounters, fire and its effects, and crash impact. NASA research in the application of laser technology to the problem of clear air turbulence detection, the development of fire resistant materials for aircraft construction, and to the improvement of seats and restraint systems to reduce crash injuries are reviewed.

  1. Strike Point Control for the National Spherical Torus Experiment (NSTX)

    SciTech Connect

    Kolemen, E.; Gates, D. A.; Rowley, C. W.; Kasdin, N. J.; Kallman, J.; Gerhardt, S.; Soukhanovskii, V.; Mueller, D.

    2010-07-09

    This paper presents the first control algorithm for the inner and outer strike point position for a Spherical Torus (ST) fusion experiment and the performance analysis of the controller. A liquid lithium divertor (LLD) will be installed on NSTX which is believed to provide better pumping than lithium coatings on carbon PFCs. The shape of the plasma dictates the pumping rate of the lithium by channeling the plasma to LLD, where strike point location is the most important shape parameter. Simulations show that the density reduction depends on the proximity of strike point to LLD. Experiments were performed to study the dynamics of the strike point, design a new controller to change the location of the strike point to desired location and stabilize it. The most effective PF coils in changing inner and outer strike points were identified using equilibrium code. The PF coil inputs were changed in a step fashion between various set points and the step response of the strike point position was obtained. From the analysis of the step responses, PID controllers for the strike points were obtained and the controller was tuned experimentally for better performance. The strike controller was extended to include the outer-strike point on the inner plate to accommodate the desired low outer-strike points for the experiment with the aim of achieving "snowflake" divertor configuration in NSTX.

  2. Review of Idealized Aircraft Wake Vortex Models

    NASA Technical Reports Server (NTRS)

    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.

  3. Small transport aircraft technology

    NASA Technical Reports Server (NTRS)

    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.

  4. High tsunami frequency as a result of combined strike-slip faulting and coastal landslides

    USGS Publications Warehouse

    Hornbach, M.J.; Braudy, N.; Briggs, R.W.; Cormier, M.-H.; Davis, M.B.; Diebold, J.B.; Dieudonne, N.; Douilly, R.; Frohlich, C.; Gulick, S.P.S.; Johnson, H. E., III; Mann, P.; McHugh, C.; Ryan-Mishkin, K.; Prentice, C.S.; Seeber, L.; Sorlien, C.C.; Steckler, M.S.; Symithe, S.J.; Taylor, F.W.; Templeton, J.

    2010-01-01

    Earthquakes on strike-slip faults can produce devastating natural hazards. However, because they consist predominantly of lateral motion, these faults are rarely associated with significant uplift or tsunami generation. And although submarine slides can generate tsunami, only a few per cent of all tsunami are believed to be triggered in this way. The 12 January Mw 7.0 Haiti earthquake exhibited primarily strike-slip motion but nevertheless generated a tsunami. Here we present data from a comprehensive field survey that covered the onshore and offshore area around the epicentre to document that modest uplift together with slope failure caused tsunamigenesis. Submarine landslides caused the most severe tsunami locally. Our analysis suggests that slide-generated tsunami occur an order-of-magnitude more frequently along the Gonave microplate than global estimates predict. Uplift was generated because of the earthquake?s location, where the Caribbean and Gonave microplates collide obliquely. The earthquake also caused liquefaction at several river deltas that prograde rapidly and are prone to failure. We conclude that coastal strike-slip fault systems such as the Enriquillog-Plantain Garden fault produce relief conducive to rapid sedimentation, erosion and slope failure, so that even modest predominantly strike-slip earthquakes can cause potentially catastrophic slide-generated tsunamig-a risk that is underestimated at present. ?? 2010 Macmillan Publishers Limited. All rights reserved.

  5. High tsunami frequency as a result of combined strike-slip faulting and coastal landslides

    USGS Publications Warehouse

    Hornbach, Matthew J.; Braudy, Nicole; Briggs, Richard W.; Cormier, Marie-Helene; Davis, Marcy B.; Diebold, John B.; Dieudonne, Nicole; Douilly, Roby; Frohlich, Cliff; Gulick, Sean P.S.; Johnson, Harold E., III; Mann, Paul; McHugh, Cecilia; Ryan-Mishkin, Katherine; Prentice, Carol S.; Seeber, Leonardo; Sorlien, Christopher C.; Steckler, Michael S.; Symithe, Steeve Julien; Taylor, Frederick W.; Templeton, John

    2010-01-01

    Earthquakes on strike-slip faults can produce devastating natural hazards. However, because they consist predominantly of lateral motion, these faults are rarely associated with significant uplift or tsunami generation. And although submarine slides can generate tsunami, only a few per cent of all tsunami are believed to be triggered in this way. The 12 January Mw 7.0 Haiti earthquake exhibited primarily strike-slip motion but nevertheless generated a tsunami. Here we present data from a comprehensive field survey that covered the onshore and offshore area around the epicentre to document that modest uplift together with slope failure caused tsunamigenesis. Submarine landslides caused the most severe tsunami locally. Our analysis suggests that slide-generated tsunami occur an order-of-magnitude more frequently along the Gonave microplate than global estimates predict. Uplift was generated because of the earthquake's location, where the Caribbean and Gonave microplates collide obliquely. The earthquake also caused liquefaction at several river deltas that prograde rapidly and are prone to failure. We conclude that coastal strike-slip fault systems such as the Enriquillo-Plantain Garden fault produce relief conducive to rapid sedimentation, erosion and slope failure, so that even modest predominantly strike-slip earthquakes can cause potentially catastrophic slide-generated tsunami - a risk that is underestimated at present.

  6. High tsunami frequency as a result of combined strike-slip faulting and coastal landslides

    NASA Astrophysics Data System (ADS)

    Hornbach, Matthew J.; Braudy, Nicole; Briggs, Richard W.; Cormier, Marie-Helene; Davis, Marcy B.; Diebold, John B.; Dieudonne, Nicole; Douilly, Roby; Frohlich, Cliff; Gulick, Sean P. S.; Johnson, Harold E., III; Mann, Paul; McHugh, Cecilia; Ryan-Mishkin, Katherine; Prentice, Carol S.; Seeber, Leonardo; Sorlien, Christopher C.; Steckler, Michael S.; Symithe, Steeve Julien; Taylor, Frederick W.; Templeton, John

    2010-11-01

    Earthquakes on strike-slip faults can produce devastating natural hazards. However, because they consist predominantly of lateral motion, these faults are rarely associated with significant uplift or tsunami generation. And although submarine slides can generate tsunami, only a few per cent of all tsunami are believed to be triggered in this way. The 12 January Mw 7.0 Haiti earthquake exhibited primarily strike-slip motion but nevertheless generated a tsunami. Here we present data from a comprehensive field survey that covered the onshore and offshore area around the epicentre to document that modest uplift together with slope failure caused tsunamigenesis. Submarine landslides caused the most severe tsunami locally. Our analysis suggests that slide-generated tsunami occur an order-of-magnitude more frequently along the Gonave microplate than global estimates predict. Uplift was generated because of the earthquake's location, where the Caribbean and Gonave microplates collide obliquely. The earthquake also caused liquefaction at several river deltas that prograde rapidly and are prone to failure. We conclude that coastal strike-slip fault systems such as the Enriquillo-Plantain Garden fault produce relief conducive to rapid sedimentation, erosion and slope failure, so that even modest predominantly strike-slip earthquakes can cause potentially catastrophic slide-generated tsunami-a risk that is underestimated at present.

  7. 49 CFR 171.16 - Detailed hazardous materials incident reports.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... quantity of hazardous waste; (3) A specification cargo tank with a capacity of 1,000 gallons or greater..., explosion or dangerous evolution of heat (i.e., an amount of heat sufficient to be dangerous to packaging or... material is not— (A) Offered for transportation or transported by aircraft, (B) A hazardous waste, or...

  8. Pool fires in a simulated aircraft cabin interior with ventilation

    NASA Technical Reports Server (NTRS)

    Bankston, C. P.; Back, L. H.; Cho, Y. I.; Shakkottai, P.

    1987-01-01

    Results of experiments conducted at the JPL to evaluate aircraft postcrash fire hazards are presented. The experiments were carried out in a one-third scale simulated aircraft cabin geometry to study pool fire and ventilation flow interactions. It is shown that wind-induced ventilation may significantly affect fire plume orientation, smoke transport, and heat fluxes and thus will affect subsequent fire spread and the immediate survivability of the passengers.

  9. Lightning Discharges to Aircraft and Associated Meteorological Conditions

    NASA Technical Reports Server (NTRS)

    Harrison, L P

    1946-01-01

    A summary is given of information on atmospheric electrical discharges to aircraft and associated meteorological conditions. Information is given that is designed to give a fairly comprehensive view of the underlying principles of meteorology and atmospheric electricity. Of special interest to pilots are lists of procedures of flight conduct and aircraft maintenance recommended foe avoiding or minimizing the hazards of disruptive electrical discharges and other severe conditions near thunderstorms.

  10. Offsite radiological consequence analysis for the bounding aircraft crash accident

    SciTech Connect

    OBERG, B.D.

    2003-03-22

    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 frequencies were determined for the Tank Farms in RPP-11736, ''Assessment Of Aircraft Crash Frequency For The Hanford Site 200 Area Tank Farms'': (1) The total aircraft crash frequency is ''extremely unlikely.'' (2) The general aviation crash frequency is ''extremely unlikely.'' (3) The helicopter crash frequency 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 frequent than ''beyond extremely unlikely,'' consequence analysis of the aircraft crash is required.

  11. Collective Bargaining and Strikes Among Physicians

    PubMed Central

    Keith, Stephen N.

    1984-01-01

    Unlike employees in other sectors of the economy, health care workers are directed toward one ultimate goal: making people well and keeping them healthy. The development of collective bargaining and union activities during this century has had a great impact on all industries in the United States and the western world. However, only in recent years have workers in the health care sector been affected by the organized labor movement. The history of collective bargaining and strikes among physicians, the key decision-makers in the health care sector, is even more recent. Because of their central position, physicians' collective activity has had and will continue to have tremendous implications for the viability of the present health care system and the quality of patient care. Even though most physicians continue to function as individual, entrepreneurial service providers and “professionals,” physicians as a group are more frequently being seen as members of a utility like industry. Their importance to individuals and society as a whole, it can be argued, is second to none; if physicians refuse to work there can be no worse set of outcomes. To estimate the potential future impact of growing collective action on the part of physicians, this article explores the general historical developments. PMID:6389889

  12. Stress interaction between subduction earthquakes and forearc strike-slip faults: Modeling and application to the northern Caribbean plate boundary

    USGS Publications Warehouse

    ten Brink, U.; Lin, J.

    2004-01-01

    Strike-slip faults in the forearc region of a subduction zone often present significant seismic hazard because of their proximity to population centers. We explore the interaction between thrust events on the subduction interface and strike-slip faults within the forearc region using three-dimensional models of static Coulomb stress change. Model results reveal that subduction earthquakes with slip vectors subparallel to the trench axis enhance the Coulomb stress on strike-slip faults adjacent to the trench but reduce the stress on faults farther back in the forearc region. In contrast, subduction events with slip vectors perpendicular to the trench axis enhance the Coulomb stress on strike-slip faults farther back in the forearc, while reducing the stress adjacent to the trench. A significant contribution to Coulomb stress increase on strike-slip faults in the back region of the forearc comes from "unclamping" of the fault, i.e., reduction in normal stress due to thrust motion on the subduction interface. We argue that although Coulomb stress changes from individual subduction earthquakes are ephemeral, their cumulative effects on the pattern of lithosphere deformation in the forearc region are significant. We use the Coulomb stress models to explain the contrasting deformation pattern between two adjacent segments of the Caribbean subduction zone. Subduction earthquakes with slip vectors nearly perpendicular to the Caribbean trench axis is dominant in the Hispaniola segment, where the strike-slip faults are more than 60 km inland from the trench. In contrast, subduction slip motion is nearly parallel to the Caribbean trench axis along the Puerto Rico segment, where the strike-slip fault is less than 15 km from the trench. This observed jump from a strike-slip fault close to the trench axis in the Puerto Rico segment to the inland faults in Hispaniola is explained by different distributions of Coulomb stress in the forearc region of the two segments, as a result

  13. Aircraft Ice Accretion Due to Large-Droplet Icing Clouds

    NASA Technical Reports Server (NTRS)

    1995-01-01

    Studies of aircraft icing due to clouds consisting of individual droplets 10 times larger than those normally found in icing conditions are being carried out by members of the NASA Lewis Research Center's Icing Technology Branch. When encountered by an aircraft in freezing conditions, clouds consisting of large water droplets have a significantly different effect than those with normal droplets. A large-water-droplet cloud has been suggested as the cause of a commuter airplane accident in the late fall of 1994. As a result, studies of what happens to aircraft flying in these rare, but potentially very hazardous, conditions have been reemphasized.

  14. Small Autonomous Aircraft Servo Health Monitoring

    NASA Technical Reports Server (NTRS)

    Quintero, Steven

    2008-01-01

    Small air vehicles offer challenging power, weight, and volume constraints when considering implementation of system health monitoring technologies. In order to develop a testbed for monitoring the health and integrity of control surface servos and linkages, the Autonomous Aircraft Servo Health Monitoring system has been designed for small Uninhabited Aerial Vehicle (UAV) platforms to detect problematic behavior from servos and the air craft structures they control, This system will serve to verify the structural integrity of an aircraft's servos and linkages and thereby, through early detection of a problematic situation, minimize the chances of an aircraft accident. Embry-Riddle Aeronautical University's rotary-winged UAV has an Airborne Power management unit that is responsible for regulating, distributing, and monitoring the power supplied to the UAV's avionics. The current sensing technology utilized by the Airborne Power Management system is also the basis for the Servo Health system. The Servo Health system measures the current draw of the servos while the servos are in Motion in order to quantify the servo health. During a preflight check, deviations from a known baseline behavior can be logged and their causes found upon closer inspection of the aircraft. The erratic behavior nay include binding as a result of dirt buildup or backlash caused by looseness in the mechanical linkages. Moreover, the Servo Health system will allow elusive problems to be identified and preventative measures taken to avoid unnecessary hazardous conditions in small autonomous aircraft.

  15. Children on hunger strike: child abuse or legitimate protest?

    PubMed

    Mok, A; Nelson, E A; Murphy, J; Hampson, A; Hendriks, J H

    1996-02-24

    The issue of children on hunger strike (voluntary total fasting) has not been reported before. The World Medical Association Declaration of Tokyo 1975 and the Declaration of Malta 1991 (revised 1992) provide clinicians with guidelines for the management of adult patients on hunger strike but do not mention children. We report the management of 14 Vietnamese children, aged 1 to 12 years, who took part in a hunger strike at a refugee detention centre in Hong Kong. PMID:8597690

  16. THE EFFECT OF HAND DOMINANCE ON MARTIAL ARTS STRIKES

    PubMed Central

    Neto, Osmar Pinto; Silva, Jansen Henrique; de Miranda Marzullo, Ana Carolina; Bolander, Richard P.; Bir, Cynthia A.

    2011-01-01

    The main goal of this study was to compare dominant and non-dominant martial arts palm strikes under different circumstances that usually happen during martial arts and combative sports applications. Seven highly experienced (10 ± 5 years) right hand dominant Kung Fu practitioners performed strikes with both hands, stances with left or right lead legs, and with the possibility or not of stepping towards the target (moving stance). Peak force was greater for the dominant hand strikes (1593.76 ± 703.45 N vs. 1042.28 ± 374.16 N; p < .001), whereas no difference was found in accuracy between the hands (p = .141). Additionally, peak force was greater for the strikes with moving stance (1448.75 ± 686.01 N vs. 1201.80 ± 547.98 N; p = .002) and left lead leg stance (1378.06 ± 705.48 N vs.1269.96 ± 547.08 N). Furthermore, the difference in peak force between strikes with moving and stationary stances was statistically significant only for the strikes performed with a left lead leg stance (p = .007). Hand speed was higher for the dominant hand strikes (5.82 ± 1.08 m/s vs. 5.24 ± 0.78 m/s; p = 0.001) and for the strikes with moving stance (5.79 ± 1.01 m/s vs. 5.29 ± 0.90 m/s; p < .001). The difference in hand speed between right and left hand strikes was only significant for strikes with moving stance. In summary, our results suggest that the stronger palm strike for a right-handed practitioner is a right hand strike on a left lead leg stance moving towards the target. PMID:22047701

  17. "Thunderstruck": penetrating thoracic injury from lightning strike.

    PubMed

    van Waes, Oscar J F; van de Woestijne, Pieter C; Halm, Jens A

    2014-04-01

    Lightning strike victims are rarely presented at an emergency department. Burns are often the primary focus. This case report describes the improvised explosive device like-injury to the thorax due to lightning strike and its treatment, which has not been described prior in (kerauno)medicine. Penetrating injury due to blast from lightning strike is extremely rare. These "shrapnel" injuries should however be ruled out in all patients struck by lightning. PMID:24054789

  18. Strong Algerian Earthquake Strikes Near Capital City

    NASA Astrophysics Data System (ADS)

    Ayadi, A.; Maouche, S.; Harbi, A.; Meghraoui, M.; Beldjoudi, H.; Oussadou, F.; Mahsas, A.; Benouar, D.; Heddar, A.; Rouchiche, Y.; Kherroubi, A.; Frogneux, M.; Lammali, K.; Benhamouda, F.; Sebaï, A.; Bourouis, S.; Alasset, P. J.; Aoudia, A.; Cakir, Z.; Merahi, M.; Nouar, O.; Yelles, A.; Bellik, A.; Briole, P.; Charade, O.; Thouvenot, F.; Semane, F.; Ferkoul, A.; Deramchi, A.; Haned, S. A.

    On 21 May 2003, a damaging earthquake of Mw 6.8 struck the region of Boumerdes 40 km east of Algiers in northern Algeria (Figure 1). The mainshock, which lasted ~ 36-40 s, had devastating effects and claimed about 2300 victims, caused more than 11,450 injuries, and left about 200,000 people homeless. It destroyed and seriously damaged around 180,000 housing units and 6000 public buildings with losses estimated at $5 billion. The mainshock was widely felt within a radius of ~ 400 km in Algeria. To the north, the earthquake was felt in southeastern Spain, including the Balearic Islands, and also in Sardinia and in southern France. The mainshock location, which was calculated at 36.91°N, 3.58°E (15 km offshore of Zemmouri; Figure 1), and the local magnitude (Md 6.4) are from seismic records of local stations. International seismological centers obtained Mw 6.8 (NEIC) with a thrust focal mechanism solution and 1.83 × 1026 dyne.cm for the seismic moment. A sequence of aftershocks affected the epicentral area with two strong shocks reaching Mw 5.8 on 27 and 29 May 2003. Field investigations allowed us to assign a maximum intensity X (European Macroseismic Scale 98) and to report rockfalls, minor surface cracks, and liquefaction phenomena. The mainshock was not associated with inland surface faulting, but one of the most striking coseismic effects is the coastal uplift and the backwash along the littoral of the Mitidja basin.

  19. NASA Now: Phase Change and Forces of Flight: Aircraft Icing Research

    NASA Video Gallery

    Tour the Icing Research Tunnel with Judith VanZante, aeromechanical engineer and icing specialist. VanZante explains the hazards of ice on aircraft, how it is formed, and why the research on ice pl...

  20. Aircraft fire safety research

    NASA Technical Reports Server (NTRS)

    Botteri, Benito P.

    1987-01-01

    During the past 15 years, very significant progress has been made toward enhancing aircraft fire safety in both normal and hostile (combat) operational environments. Most of the major aspects of the aircraft fire safety problem are touched upon here. The technology of aircraft fire protection, although not directly applicable in all cases to spacecraft fire scenarios, nevertheless does provide a solid foundation to build upon. This is particularly true of the extensive research and testing pertaining to aircraft interior fire safety and to onboard inert gas generation systems, both of which are still active areas of investigation.

  1. Hypersonic aircraft design

    NASA Technical Reports Server (NTRS)

    Alkamhawi, Hani; Greiner, Tom; Fuerst, Gerry; Luich, Shawn; Stonebraker, Bob; Wray, Todd

    1990-01-01

    A hypersonic aircraft is designed which uses scramjets to accelerate from Mach 6 to Mach 10 and sustain that speed for two minutes. Different propulsion systems were considered and it was decided that the aircraft would use one full scale turbofan-ramjet. Two solid rocket boosters were added to save fuel and help the aircraft pass through the transonic region. After considering aerodynamics, aircraft design, stability and control, cooling systems, mission profile, and landing systems, a conventional aircraft configuration was chosen over that of a waverider. The conventional design was chosen due to its landing characteristics and the relative expense compared to the waverider. Fuel requirements and the integration of the engine systems and their inlets are also taken into consideration in the final design. A hypersonic aircraft was designed which uses scramjets to accelerate from Mach 6 to Mach 10 and sustain that speed for two minutes. Different propulsion systems were considered and a full scale turbofan-ramjet was chosen. Two solid rocket boosters were added to save fuel and help the aircraft pass through the transonic reqion. After the aerodynamics, aircraft design, stability and control, cooling systems, mission profile, landing systems, and their physical interactions were considered, a conventional aircraft configuration was chosen over that of a waverider. The conventional design was chosen due to its landing characteristics and the relative expense compared to the waverider. Fuel requirements and the integration of the engine systems and their inlets were also considered in the designing process.

  2. Manifestations of Strike-Slip Faulting on Ganymede

    NASA Technical Reports Server (NTRS)

    DeRemer, Lindsay C.; Pappalardo, Robert T.

    2003-01-01

    Voyager images of Ganymede suggested that strike-slip faulting may have taken place [1, 2], but the role of this process in shaping grooved terrain was uncertain. In Galileo high-resolution images of Ganymede's surface, we recognize three signature features of strike-slip faulting: (1) en echelon structures, (2) strike-slip duplexes, and (3) offset preexisting features. We have undertaken a study to recognize and map these features, and identify any morphological progressions of strike-slip features. This will allow a better understanding of the structural history of Ganymede, and the formation and evolution of grooved terrain.

  3. Debunking the viper's strike: harmless snakes kill a common assumption.

    PubMed

    Penning, David A; Sawvel, Baxter; Moon, Brad R

    2016-03-01

    To survive, organisms must avoid predation and acquire nutrients and energy. Sensory systems must correctly differentiate between potential predators and prey, and elicit behaviours that adjust distances accordingly. For snakes, strikes can serve both purposes. Vipers are thought to have the fastest strikes among snakes. However, strike performance has been measured in very few species, especially non-vipers. We measured defensive strike performance in harmless Texas ratsnakes and two species of vipers, western cottonmouths and western diamond-backed rattlesnakes, using high-speed video recordings. We show that ratsnake strike performance matches or exceeds that of vipers. In contrast with the literature over the past century, vipers do not represent the pinnacle of strike performance in snakes. Both harmless and venomous snakes can strike with very high accelerations that have two key consequences: the accelerations exceed values that can cause loss of consciousness in other animals, such as the accelerations experienced by jet pilots during extreme manoeuvres, and they make the strikes faster than the sensory and motor responses of mammalian prey and predators. Both harmless and venomous snakes can strike faster than the blink of an eye and often reach a target before it can move. PMID:26979562

  4. Vortex Wakes of Subsonic Transport Aircraft

    NASA Technical Reports Server (NTRS)

    Rossow, Vernon J.; Nixon, David (Technical Monitor)

    1999-01-01

    A historical overview will be presented of the research conducted on the structure and modification of the vortices generated by the lifting surfaces of subsonic transport aircraft. The seminar will describe the three areas of vortex research; namely, the magnitude of the hazard posed, efforts to reduce the hazard to an acceptable level, and efforts to develop a systematic means for avoiding vortex wakes. It is first pointed out that the characteristics of lift-generated vortices are related to the aerodynamic shapes that produce them and that various arrangements of surfaces can be used to produce different vortex structures. The largest portion of the research conducted to date has been directed at finding ways to reduce the hazard potential of lift-generated vortices shed by subsonic transport aircraft in the vicinity of airports during landing and takeoff operations. It is stressed that lift-generated vortex wakes are so complex that progress towards a solution requires application of a combined theoretical and experimental research program because either alone often leads to incorrect conclusions. It is concluded that a satisfactory aerodynamic solution to the wake-vortex problem at airports has not yet been found but a reduction in the impact of the wake-vortex hazard on airport capacity may become available in the foreseeable future through wake-vortex avoidance concepts currently under study. The material to be presented in this overview is drawn from articles published in aerospace journals that are available publicly.

  5. 49 CFR 172.512 - Freight containers and aircraft unit load devices.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... aircraft unit load device if it is only transported by air and is identified as containing a hazardous... 49 Transportation 2 2011-10-01 2011-10-01 false Freight containers and aircraft unit load devices... INFORMATION, TRAINING REQUIREMENTS, AND SECURITY PLANS Placarding § 172.512 Freight containers and...

  6. Moral hazard.

    PubMed

    Chambers, David W

    2009-01-01

    Civil societies set aside a common pool of resources to help those with whom chance has dealt harshly. Frequently we allow access to these common resources when bad luck is assisted by foolishness and lack of foresight. Sometimes we may even help ourselves to a few of those common assets since others are doing so and they are public goods, the cost of which is shared and has already been paid. Moral hazard is the questionable ethical practice of increasing opportunity for individual gain while shifting risk for loss to the group. Bailout is an example. What makes moral hazard so widespread and difficult to manage is that it is easier for individuals to see their advantage than it is for groups to see theirs. Runaway American healthcare costs can be explained in these terms. Cheating, overtreatment, commercialism, and other moral problems in dentistry can be traced to the interaction between opportunistic individual behavior and permissive group responses common in moral hazard. PMID:19928367

  7. Human Factors In Aircraft Automation

    NASA Technical Reports Server (NTRS)

    Billings, Charles

    1995-01-01

    Report presents survey of state of art in human factors in automation of aircraft operation. Presents examination of aircraft automation and effects on flight crews in relation to human error and aircraft accidents.

  8. General Aviation Aircraft Reliability Study

    NASA Technical Reports Server (NTRS)

    Pettit, Duane; Turnbull, Andrew; Roelant, Henk A. (Technical Monitor)

    2001-01-01

    This reliability study was performed in order to provide the aviation community with an estimate of Complex General Aviation (GA) Aircraft System reliability. To successfully improve the safety and reliability for the next generation of GA aircraft, a study of current GA aircraft attributes was prudent. This was accomplished by benchmarking the reliability of operational Complex GA Aircraft Systems. Specifically, Complex GA Aircraft System reliability was estimated using data obtained from the logbooks of a random sample of the Complex GA Aircraft population.

  9. Cable Tensiometer for Aircraft

    NASA Technical Reports Server (NTRS)

    Nunnelee, Mark (Inventor)

    2008-01-01

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

  10. Lightning protection of aircraft

    NASA Technical Reports Server (NTRS)

    Fisher, F. A.; Plumer, J. A.

    1977-01-01

    The current knowledge concerning potential lightning effects on aircraft and the means that are available to designers and operators to protect against these effects are summarized. The increased use of nonmetallic materials in the structure of aircraft and the constant trend toward using electronic equipment to handle flight-critical control and navigation functions have served as impetus for this study.

  11. Civil aircraft accident investigation.

    PubMed

    Haines, Daniel

    2013-01-01

    This talk reviews some historic aircraft accidents and some more recent. It reflects on the division of accident causes, considering mechanical failures and aircrew failures, and on aircrew training. Investigation results may lead to improved aircraft design, and to appropriate crew training. PMID:24057309

  12. Enhanced Airport Capacity Through Safe, Dynamic Reductions in Aircraft Separation: NASA's Aircraft VOrtex Spacing System (AVOSS)

    NASA Technical Reports Server (NTRS)

    OConnor, Cornelius J.; Rutishauser, David K.

    2001-01-01

    An aspect of airport terminal operations that holds potential for efficiency improvements is the separation criteria applied to aircraft for wake vortex avoidance. These criteria evolved to represent safe spacing under weather conditions conducive to the longest wake hazards, and are consequently overly conservative during a significant portion of operations. Under many ambient conditions, such as moderate crosswinds or turbulence, wake hazard durations are substantially reduced. To realize this reduction NASA has developed a proof-of-concept Aircraft Vortex Spacing System (AVOSS). Successfully operated in a real-time field demonstration during July 2000 at the Dallas Ft. Worth International Airport, AVOSS is a novel integration of weather sensors, wake sensors, and analytical wake prediction algorithms. Gains in airport throughput using AVOSS spacing as compared to the current criteria averaged 6%, with peak values approaching the theoretical maximum of 16%. The average throughput gain translates to 15-40% reductions in delay when applied to realistic capacity ratios at major airports.

  13. 14 CFR 25.631 - Bird strike damage.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 14 Aeronautics and Space 1 2014-01-01 2014-01-01 false Bird strike damage. 25.631 Section 25.631... STANDARDS: TRANSPORT CATEGORY AIRPLANES Design and Construction General § 25.631 Bird strike damage. The... airplane after impact with an 8-pound bird when the velocity of the airplane (relative to the bird...

  14. 14 CFR 25.631 - Bird strike damage.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 14 Aeronautics and Space 1 2012-01-01 2012-01-01 false Bird strike damage. 25.631 Section 25.631... STANDARDS: TRANSPORT CATEGORY AIRPLANES Design and Construction General § 25.631 Bird strike damage. The... airplane after impact with an 8-pound bird when the velocity of the airplane (relative to the bird...

  15. 14 CFR 25.631 - Bird strike damage.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 14 Aeronautics and Space 1 2013-01-01 2013-01-01 false Bird strike damage. 25.631 Section 25.631... STANDARDS: TRANSPORT CATEGORY AIRPLANES Design and Construction General § 25.631 Bird strike damage. The... airplane after impact with an 8-pound bird when the velocity of the airplane (relative to the bird...

  16. Gratifications Lost: The 1985 Philadelphia Newspaper Strike and Media Use.

    ERIC Educational Resources Information Center

    Elliott, William R.; Rosenberg, William L.

    A study examined the relationship between newspaper gratifications sought and media use during and after a 1985 strike by unions of two Philadelphia newspapers, and the compensatory media behaviors, if any, people adopted to make up for the loss of their daily newspaper(s). It was hypothesized that during the strike, people would read more…

  17. 14 CFR 25.631 - Bird strike damage.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 14 Aeronautics and Space 1 2011-01-01 2011-01-01 false Bird strike damage. 25.631 Section 25.631... STANDARDS: TRANSPORT CATEGORY AIRPLANES Design and Construction General § 25.631 Bird strike damage. The... airplane after impact with an 8-pound bird when the velocity of the airplane (relative to the bird...

  18. 14 CFR 25.631 - Bird strike damage.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Bird strike damage. 25.631 Section 25.631... STANDARDS: TRANSPORT CATEGORY AIRPLANES Design and Construction General § 25.631 Bird strike damage. The... airplane after impact with an 8-pound bird when the velocity of the airplane (relative to the bird...

  19. Using Grids to Teach the Skill of Striking

    ERIC Educational Resources Information Center

    Horton, Mel L.

    2006-01-01

    This article discusses the grid system as a strategy for enhancing the skill of striking in physical education. A grid system is a box or rectangle-defined space in which students practice specific skills or strategies in pairs or small groups. Here, the author provides sample activities that can be used with grids to teach striking skills for…

  20. Strikes, Arbitration, and Teacher Salaries: A Behavioral Analysis.

    ERIC Educational Resources Information Center

    Delaney, John Thomas

    1983-01-01

    Using a behavioral theory of bargaining, the authors examined data sets from Illinois and Iowa school districts and from a national sample of teachers. Results suggest that strike use and the availability of arbitration and the right to strike affect teacher salaries, while arbitration use does not. (Author/SK)

  1. Desperate Measures: Strikes and Wages in Post-Accord America

    ERIC Educational Resources Information Center

    Rosenfeld, Jake

    2006-01-01

    Using previously unreleased data on nearly every authorized work stoppage that occurred between 1984 and 2002, this paper tests whether the positive wage-strike relationship held following the breakdown of the post-war labor-capital accord. Unlike in decades past, these findings indicate a complete decoupling of the wage-strike relationship. Even…

  2. Aircraft operations management manual

    NASA Technical Reports Server (NTRS)

    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.

  3. Why aircraft disinsection?

    PubMed Central

    Gratz, N. G.; Steffen, R.; Cocksedge, W.

    2000-01-01

    A serious problem is posed by the inadvertent transport of live mosquitoes aboard aircraft arriving from tropical countries where vector-borne diseases are endemic. Surveys at international airports have found many instances of live insects, particularly mosquitoes, aboard aircraft arriving from countries where malaria and arboviruses are endemic. In some instances mosquito species have been established in countries in which they have not previously been reported. A serious consequence of the transport of infected mosquitoes aboard aircraft has been the numerous cases of "airport malaria" reported from Europe, North America and elsewhere. There is an important on-going need for the disinsection of aircraft coming from airports in tropical disease endemic areas into nonendemic areas. The methods and materials available for use in aircraft disinsection and the WHO recommendations for their use are described. PMID:10994283

  4. Hypersonic reconnaissance aircraft

    NASA Technical Reports Server (NTRS)

    Bulk, Tim; Chiarini, David; Hill, Kevin; Kunszt, Bob; Odgen, Chris; Truong, Bon

    1992-01-01

    A conceptual design of a hypersonic reconnaissance aircraft for the U.S. Navy is discussed. After eighteen weeks of work, a waverider design powered by two augmented turbofans was chosen. The aircraft was designed to be based on an aircraft carrier and to cruise 6,000 nautical miles at Mach 4;80,000 feet and above. As a result the size of the aircraft was only allowed to have a length of eighty feet, fifty-two feet in wingspan, and roughly 2,300 square feet in planform area. Since this is a mainly cruise aircraft, sixty percent of its 100,000 pound take-off weight is JP fuel. At cruise, the highest temperature that it will encounter is roughly 1,100 F, which can be handled through the use of a passive cooling system.

  5. Risk Considerations of Bird Strikes to Space Launch Vehicles

    NASA Technical Reports Server (NTRS)

    Hales, Christy; Ring, Robert

    2016-01-01

    Within seconds after liftoff of the Space Shuttle during mission STS-114, a turkey vulture impacted the vehicle's external tank. The contact caused no apparent damage to the Shuttle, but the incident led NASA to consider the potential consequences of bird strikes during a Shuttle launch. The environment at Kennedy Space Center provides unique bird strike challenges due to the Merritt Island National Wildlife Refuge and the Atlantic Flyway bird migration routes. NASA is currently refining risk assessment estimates for the probability of bird strike to space launch vehicles. This paper presents an approach for analyzing the risks of bird strikes to space launch vehicles and presents an example. The migration routes, types of birds present, altitudes of those birds, exposed area of the launch vehicle, and its capability to withstand impacts affect the risk due to bird strike. A summary of significant risk contributors is discussed.

  6. Strike Point Control on EAST Using an Isoflux Control Method

    NASA Astrophysics Data System (ADS)

    Xing, Zhe; Xiao, Bingjia; Luo, Zhengping; L. Walker, M.; A. Humphreys, D.

    2015-09-01

    For the advanced tokamak, the particle deposition and thermal load on the divertor is a big challenge. By moving the strike points on divertor target plates, the position of particle deposition and thermal load can be shifted. We could adjust the Poloidal Field (PF) coil current to achieve the strike point position feedback control. Using isoflux control method, the strike point position can be controlled by controlling the X point position. On the basis of experimental data, we establish relational expressions between X point position and strike point position. Benchmark experiments are carried out to validate the correctness and robustness of the control methods. The strike point position is successfully controlled following our command in the EAST operation. supported by the National Magnetic Confinement Fusion Science Program of China (Nos. 2012GB105000 and 2014GB103000)

  7. Transportation of hazardous materials

    SciTech Connect

    Not Available

    1986-07-01

    This report discusses the following: data and information systems for hazardous-materials; containers for hazardous-materials transportation; hazardous-materials transportation regulation; and training for hazardous-materials transportation enforcement and emergency response.

  8. A Telerobotics Architecture for Aircraft Maintenance and Remanufacturing

    NASA Technical Reports Server (NTRS)

    Backes, P. G.; Zimmerman, W.; Leahy, M. B., Jr.

    1994-01-01

    The application of telerobotics to aircraft depot maintenance and remanufacturing is described and a telerobotics architecture for the application is discussed. Telerobotics will enhance process quality and could potentially decrease turn-around time and costs while moving human operatiors from hazardous work areas to safe and comfortable operator control stations.

  9. An Automated System to Quantify Convectively induced Aircraft encounters with Turbulence over Europe and North Atlantic

    NASA Astrophysics Data System (ADS)

    Meneguz, Elena; Turp, Debi; Wells, Helen

    2015-04-01

    It is well known that encounters with moderate or severe turbulence can lead to passenger injuries and incur high costs for airlines from compensation and litigation. As one of two World Area Forecast Centres (WAFCs), the Met Office has responsibility for forecasting en-route weather hazards worldwide for aviation above a height of 10,000 ft. Observations from commercial aircraft provide a basis for gaining a better understanding of turbulence and for improving turbulence forecasts through verification. However there is currently a lack of information regarding the possible cause of the observed turbulence, or whether the turbulence occurred within cloud. Such information would be invaluable for the development of forecasting techniques for particular types of turbulence and for forecast verification. Of all the possible sources of turbulence, convective activity is believed to be a major cause of turbulence. Its relative importance over the Europe and North Atlantic area has not been yet quantified in a systematic way: in this study, a new approach is developed to automate identification of turbulent encounters in the proximity of convective clouds. Observations of convection are provided from two independent sources: a surface based lightning network and satellite imagery. Lightning observations are taken from the Met Office Arrival Time Detections network (ATDnet). ATDnet has been designed to identify cloud-to-ground flashes over Europe but also detects (a smaller fraction of) strikes over the North Atlantic. Meteosat Second Generation (MSG) satellite products are used to identify convective clouds by applying a brightness temperature filtering technique. The morphological features of cold cloud tops are also investigated. The system is run for all in situ turbulence reports received from airlines for a total of 12 months during summer 2013 and 2014 for the domain of interest. Results of this preliminary short term climatological study show significant intra

  10. Relative tectonic activity assessment along the East Anatolian strike-slip fault, Eastern Turkey

    NASA Astrophysics Data System (ADS)

    Khalifa, Abdelrahman

    2016-04-01

    The East Anatolian transform fault is a morphologically distinct and seismically active left-lateral strike-slip fault that extends for ~ 500 km from Karlıova to the Maraş defining the boundary between the Anatolian Block and Syrian Foreland. Deformed landforms along the East Anatolian fault provide important insights into the nature of landscape development within an intra-continental strike-slip fault system. Geomorphic analysis of the East Anatolian fault using geomorphic indices including mountain front sinuosity, stream length-gradient index, drainage density, hypsometric integral, and the valley-width to valley height ratio helped differentiate the faulting into segments of differing degrees of the tectonic and geomorphic activity. Watershed maps for the East Anatolian fault showing the relative relief, incision, and maturity of basins along the fault zone help define segments of the higher seismic risk and help evaluate the regional seismic hazard. The results of the geomorphic indices show a high degree of activity, reveal each segment along the fault is active and represent a higher seismic hazard along the entire fault.

  11. Transportation of Hazardous Evidentiary Material.

    SciTech Connect

    Osborn, Douglas.

    2005-06-01

    This document describes the specimen and transportation containers currently available for use with hazardous and infectious materials. A detailed comparison of advantages, disadvantages, and costs of the different technologies is included. Short- and long-term recommendations are also provided.3 DraftDraftDraftExecutive SummaryThe Federal Bureau of Investigation's Hazardous Materials Response Unit currently has hazardous material transport containers for shipping 1-quart paint cans and small amounts of contaminated forensic evidence, but the containers may not be able to maintain their integrity under accident conditions or for some types of hazardous materials. This report provides guidance and recommendations on the availability of packages for the safe and secure transport of evidence consisting of or contaminated with hazardous chemicals or infectious materials. Only non-bulk containers were considered because these are appropriate for transport on small aircraft. This report will addresses packaging and transportation concerns for Hazardous Classes 3, 4, 5, 6, 8, and 9 materials. If the evidence is known or suspected of belonging to one of these Hazardous Classes, it must be packaged in accordance with the provisions of 49 CFR Part 173. The anthrax scare of several years ago, and less well publicized incidents involving unknown and uncharacterized substances, has required that suspicious substances be sent to appropriate analytical laboratories for analysis and characterization. Transportation of potentially hazardous or infectious material to an appropriate analytical laboratory requires transport containers that maintain both the biological and chemical integrity of the substance in question. As a rule, only relatively small quantities will be available for analysis. Appropriate transportation packaging is needed that will maintain the integrity of the substance, will not allow biological alteration, will not react chemically with the substance being

  12. 75 FR 78229 - Record of Decision for the U.S. Marine Corps West Coast Basing of the F-35B Aircraft

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-12-15

    ... operate 11 operational F-35B Joint Strike Fighter (JSF) squadrons (up to 16 aircraft per squadron, for a... squadron at MCAS Yuma in Arizona. Each operational squadron will consist of up to 16 F-35B aircraft. To... Department of the Navy Record of Decision for the U.S. Marine Corps West Coast Basing of the F-35B...

  13. 75 FR 78229 - Record of Decision for the U.S. Marine Corps East Coast Basing of the F-35B Aircraft

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-12-15

    ... operate 11 operational F-35B Joint Strike Fighter (JSF) squadrons (up to 16 aircraft per squadron, for a... Department of the Navy Record of Decision for the U.S. Marine Corps East Coast Basing of the F-35B Aircraft... Alternative, which includes basing three F-35B operational squadrons and the PTC at Marine Corps Air...

  14. Predicting visibility of aircraft.

    PubMed

    Watson, Andrew; Ramirez, Cesar V; Salud, Ellen

    2009-01-01

    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. PMID:19462007

  15. Predicting Visibility of Aircraft

    PubMed Central

    Watson, Andrew; Ramirez, Cesar V.; Salud, Ellen

    2009-01-01

    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. PMID:19462007

  16. Strikes by physicians: a historical perspective toward an ethical evaluation.

    PubMed

    Thompson, Stephen L; Salmon, J Warren

    2006-01-01

    Current conditions surrounding the house of medicine-including corporate and government cost-containment strategies, increasing market-penetration schemes in health care, along with clinical scrutiny and the administrative control imposed under privatization by managed care firms, insurance companies, and governments-have spurred an upsurge in physician unionization, which requires a revisiting of the issue of physician strikes. Strikes by physicians have been relatively rare events in medical history. When they have occurred, they have aroused intense debate over their ethical justification among professionals and the public alike, notwithstanding what caused the strikes. As physicians and other health care providers increasingly find employment within organizations as wage-contract employees and their work becomes more highly rationalized, more physicians will join labor organizations to protect both their economic and their professional interests. As a result, these physicians will have to come to terms with the use of the strike weapon. On the surface, many health care strikes may not ever seem justifiable, but in certain defined situations a strike would be not only permissible but an ethical imperative. With an exacerbation of labor strife in the health sector in many nations, it is crucial to explore the question of what constitutes an ethical physician strike. PMID:16878396

  17. [Physicians' strikes and health services: an ethical perspective].

    PubMed

    Goić, A

    1996-07-01

    For the public opinion, medical strikes are a controversial issue; physician's ethical judgments are also different. The present article analyses the requisites to consider legitimate a strike and, based on these, the ethical duties of physicians; the features of medical unionism; the ethical duties of authority; the manipulation of ill people by the strike and the social factors that may cause these conflicts. In a medical strike, universal ethical values based on the Hyppocratic oath and promoted by the profession, are endangered. This article concludes that a medical strike may be explainable due to different reasons, but it is not ethically justifiable beyond any doubt. The health profession that is not prepared to give up strikes as gremial pressure tool, should not choose a profession that takes care of the ill. The best way to avoid medical strike is to prevent them: the society and the authority have the ethical obligation to create work conditions that elude conflicts. To settle disputes between physicians and health institutions, the creation of a permanent arbitral instance agreed by physicians and the authority, i.e. a high level committee integrated by respected individuals and physicians, could be necessary. This committee should send forth veredicts that would be obeyed by the contending parties. PMID:9138378

  18. Structural Health Monitoring of AN Aircraft Joint

    NASA Astrophysics Data System (ADS)

    Mickens, T.; Schulz, M.; Sundaresan, M.; Ghoshal, A.; Naser, A. S.; Reichmeider, R.

    2003-03-01

    A major concern with ageing aircraft is the deterioration of structural components in the form of fatigue cracks at fastener holes, loose rivets and debonding of joints. These faults in conjunction with corrosion can lead to multiple-site damage and pose a hazard to flight. Developing a simple vibration-based method of damage detection for monitoring ageing structures is considered in this paper. The method is intended to detect damage during operation of the vehicle before the damage can propagate and cause catastrophic failure of aircraft components. It is typical that only a limited number of sensors could be used on the structure and damage can occur anywhere on the surface or inside the structure. The research performed was to investigate use of the chirp vibration responses of an aircraft wing tip to detect, locate and approximately quantify damage. The technique uses four piezoelectric patches alternatively as actuators and sensors to send and receive vibration diagnostic signals.Loosening of selected screws simulated damage to the wing tip. The results obtained from the testing led to the concept of a sensor tape to detect damage at joints in an aircraft structure.

  19. Local avian density influences risk of mortality from window strikes.

    PubMed

    Sabo, Ann M; Hagemeyer, Natasha D G; Lahey, Ally S; Walters, Eric L

    2016-01-01

    Up to a billion birds die per year in North America as a result of striking windows. Both transparent and reflective glass panes are a cause for concern, misleading birds by either acting as invisible, impenetrable barriers to desired resources, or reflecting those resources over a large surface area. A high number of window strikes occur during migration, but little is known about the factors of susceptibility, or whether particular avian taxa are more vulnerable than others. We report on a study of window strikes and mist-netting data at the Virginia Zoological Park (Norfolk, Virginia, USA), conducted in the autumn of 2013 and 2014. We focused on three factors likely to contribute to an individual's predisposition to collide with windows: (i) taxonomic classification, (ii) age, and (iii) migrant vs. resident status. Thrushes, dominated by the partial migrant American Robin (Turdus migratorius), were significantly less likely to strike glass than be sampled in mist nets (χ(2) = 9.21, p = 0.002), while wood-warblers (Parulidae) were more likely to strike than expected (χ(2) = 13.55, p < 0.001). The proportion of juveniles striking windows (45.4%) was not significantly different (χ(2) = 0.05, p = 0.827) than the population of juvenile birds naturally occurring at the zoo (48.8%). Migrants, however, were significantly more susceptible to window strikes than residents (χ(2) = 6.35, p = 0.012). Our results suggest that resident birds are able to learn to avoid and thus reduce their likelihood of striking windows; this intrinsic risk factor may help explain the apparent susceptibility of certain taxa to window strikes. PMID:27366656

  20. Local avian density influences risk of mortality from window strikes

    PubMed Central

    Sabo, Ann M.; Hagemeyer, Natasha D.G.; Lahey, Ally S.

    2016-01-01

    Up to a billion birds die per year in North America as a result of striking windows. Both transparent and reflective glass panes are a cause for concern, misleading birds by either acting as invisible, impenetrable barriers to desired resources, or reflecting those resources over a large surface area. A high number of window strikes occur during migration, but little is known about the factors of susceptibility, or whether particular avian taxa are more vulnerable than others. We report on a study of window strikes and mist-netting data at the Virginia Zoological Park (Norfolk, Virginia, USA), conducted in the autumn of 2013 and 2014. We focused on three factors likely to contribute to an individual’s predisposition to collide with windows: (i) taxonomic classification, (ii) age, and (iii) migrant vs. resident status. Thrushes, dominated by the partial migrant American Robin (Turdus migratorius), were significantly less likely to strike glass than be sampled in mist nets (χ2 = 9.21, p = 0.002), while wood-warblers (Parulidae) were more likely to strike than expected (χ2 = 13.55, p < 0.001). The proportion of juveniles striking windows (45.4%) was not significantly different (χ2 = 0.05, p = 0.827) than the population of juvenile birds naturally occurring at the zoo (48.8%). Migrants, however, were significantly more susceptible to window strikes than residents (χ2 = 6.35, p = 0.012). Our results suggest that resident birds are able to learn to avoid and thus reduce their likelihood of striking windows; this intrinsic risk factor may help explain the apparent susceptibility of certain taxa to window strikes. PMID:27366656

  1. Loftin Collection - Boeing Aircraft

    NASA Technical Reports Server (NTRS)

    1933-01-01

    Either a F2B-1 or F3B-1, both aircraft were built by Boeing and both were powered by Pratt and Whitney Wasp engines. These fighters were intended for Navy shipboard use. Boeing F3B-1: While most Boeing F3B-1s served the U. S. Navy aircraft carriers the Lexington and the Saratoga, this example flew in NACA hands at the Langley Memorial Aeronautical Laboratory in the late 1920's. Also known as the Boeing Model 77, the aircraft was the next to last F3B-1 build in November 1928.

  2. OVRhyp, Scramjet Test Aircraft

    NASA Technical Reports Server (NTRS)

    Aslan, J.; Bisard, T.; Dallinga, S.; Draper, K.; Hufford, G.; Peters, W.; Rogers, J.

    1990-01-01

    A preliminary design for an unmanned hypersonic research vehicle to test scramjet engines is presented. The aircraft will be launched from a carrier aircraft at an altitude of 40,000 feet at Mach 0.8. The vehicle will then accelerate to Mach 6 at an altitude of 100,000 feet. At this stage the prototype scramjet will be employed to accelerate the vehicle to Mach 10 and maintain Mach 10 flight for 2 minutes. The aircraft will then decelerate and safely land.

  3. Some fighter aircraft trends

    NASA Technical Reports Server (NTRS)

    Spearman, L.

    1985-01-01

    Some basic trends in fighters are traced from the post World II era. Beginning with the first operational jet fighter, the P-80, the characteristics of subsequent fighter aircraft are examined for performance, mission capability, effectiveness, and cost. Characteristics presented include: power loading, wing loading, maximum speed, rate of climb, turn rate, weight and weight distribution, cost and cost distribution. The characteristics of some USSR aircraft are included for comparison. The trends indicate some of the rationale for certain fighter designs and some likely characteristics to be sought in future fighter aircraft designs.

  4. Tropospheric sampling with aircraft

    SciTech Connect

    Daum, P.H.; Springston, S.R.

    1991-03-01

    Aircraft constitute a unique environment which places stringent requirements on the instruments used to measure the concentrations of atmospheric trace gases and aerosols. Some of these requirements such as minimization of size, weight, and power consumption are general; others are specific to individual techniques. This review presents the basic principles and considerations governing the deployment of trace gas and aerosol instrumentation on an aircraft. An overview of common instruments illustrates these points and provides guidelines for designing and using instruments on aircraft-based measurement programs.

  5. Aircraft compass characteristics

    NASA Technical Reports Server (NTRS)

    Peterson, John B; Smith, Clyde W

    1937-01-01

    A description of the test methods used at the National Bureau of Standards for determining the characteristics of aircraft compasses is given. The methods described are particularly applicable to compasses in which mineral oil is used as the damping liquid. Data on the viscosity and density of certain mineral oils used in United States Navy aircraft compasses are presented. Characteristics of Navy aircraft compasses IV to IX and some other compasses are shown for the range of temperatures experienced in flight. Results of flight tests are presented. These results indicate that the characteristic most desired in a steering compass is a short period and, in a check compass, a low overswing.

  6. Microwave imaging of aircraft

    NASA Astrophysics Data System (ADS)

    Steinberg, Bernard D.

    1988-12-01

    Three methods of imaging aircraft from the ground with microwave radar with quality suitable for aircraft target recognition are described. The imaging methods are based on a self-calibration procedure called adaptive beamforming that compensates for the severe geometric distortion inherent in any imaging system that is large enough to achieve the high angular resolution necessary for two-dimensional target imaging. The signal processing algorithm is described and X-band (3-cm)-wavelength experiments demonstrate its success on commercial aircraft flying into Philadelphia International Airport.

  7. Aircraft modifications: Assessing the current state of Air Force aircraft modifications and the implications for future military capability

    NASA Astrophysics Data System (ADS)

    Hill, Owen Jacob

    How prepared is the U.S. Air Force to modify its aircraft fleet in upcoming years? Aircraft modernization is a complex interaction of new and legacy aircraft, organizational structure, and planning policy. This research will take one component of modernization: aircraft modification, and apply a new method of analysis in order to help formulate policy to promote modernization. Departing from previous small-sample studies dependent upon weight as a chief explanatory variable, this dissertation incorporates a comprehensive dataset that was constructed for this research of all aircraft modifications from 1996 through 2005. With over 700 modification programs, this dataset is used to examine changes to the current modification policy using policy-response regression models. These changes include separating a codependent procurement and installation schedule, reducing the documentation requirements for safety modifications, and budgeting for aging aircraft modifications. The research then concludes with predictive models for the F-15 and F-16 along with their replacements: the F-22 and F-35 Joint Strike Fighter.

  8. Physicians' strikes and the competing bases of physicians' moral obligations.

    PubMed

    MacDougall, D Robert

    2013-09-01

    Many authors have addressed the morality of physicians' strikes on the assumption that medical practice is morally different from other kinds of occupations. This article analyzes three prominent theoretical accounts that attempt to ground such special moral obligations for physicians--practice-based accounts, utilitarian accounts, and social contract accounts--and assesses their applicability to the problem of the morality of strikes. After critiquing these views, it offers a fourth view grounding special moral obligations in voluntary commitments, and explains why this is a preferable basis for understanding physicians' moral obligations in general and especially as pertaining to strikes. PMID:24199524

  9. Exhumation and continental strike-slip fault systems: Introduction

    USGS Publications Warehouse

    Roeske, S.M.; Till, A.B.; Foster, D.A.; Sample, J.C.

    2007-01-01

    Metamorphic rocks adjacent to and within strike-slip faultsystems occur in a wide range of tectonic settings. Detailed studies show that for a number of these locales a significant part of the exhumation occurred during strike-slip fault motion, but the specific processes involved are often cryptic. Although some sites share characteristic features, such as metamorphic rocks exhumed in extensional step-overs within overall transtensional systems, no one common theme emerges from all of the studies. Our understanding of the variables that control continental strike-slip faults' interaction with mid- to lower-crustal structures is still primitive.

  10. Pre/post-strike atmospheric assessment system (PAAS)

    SciTech Connect

    Peglow, S. G., LLNL; Molitoris, J. D., LLNL

    1997-02-03

    The Pre/Post-Strike Atmospheric Assessment System was proposed to show the importance of local meteorological conditions in the vicinity of a site suspected of storing or producing toxic agents and demonstrate a technology to measure these conditions, specifically wind fields. The ability to predict the collateral effects resulting from an attack on a facility containing hazardous materials is crucial to conducting effective military operations. Our study approach utilized a combination of field measurements with dispersion modeling to better understand which variables in terrain and weather were most important to collateral damage predictions. To develop the PAAS wind-sensing technology, we utilized a combination of emergent and available technology from micro-Doppler and highly coherent laser systems. The method used for wind sensing is to probe the atmosphere with a highly coherent laser beam. As the beam probes, light is back-scattered from particles entrained in the air to the lidar transceiver and detected by the instrument. Any motion of the aerosols with a component along the beam axis leads to a Doppler shift of the received light. Scanning in a conical fashion about the zenith results in a more accurate and two-dimensional measurement of the wind velocity. The major milestones in the benchtop system development were to verify the design by demonstrating the technique in the laboratory, then scale the design down to a size consistent with a demonstrator unit which could be built to take data in the field. The micro-Doppler heterodyne system we developed determines absolute motion by optically mixing a reference beam with the return signal and has shown motion sensitivity to better than 1 cm/s. This report describes the rationale, technical approach and laboratory testing undertaken to demonstrate the feasibility and utility of a system to provide local meteorological data and predict atmospheric particulate motion. The work described herein was funded by

  11. Lidar windshear detection for commercial aircraft

    NASA Technical Reports Server (NTRS)

    Targ, Russell; Bowles, Roland L.

    1991-01-01

    As part of the NASA/FAA National Integrated Windshear Program, a measurable windshear hazard index that can be remotely sensed from an aircraft is presented. This will provide a pilot information about the wind conditions he will experience at some later time if he continues along the present flight path. The technology analysis and end-to-end performance simulation, which measured S/N and resulting wind velocity errors for competing lidar systems, demonstrated that a Ho:YAG lidar at a wavelength of 2.1 microns and a CO2 lidar at 10.6 microns can give the pilot data about the line-of-sight component of a windshear threat in an area extending from his present position to two to four km in front of the aircraft.

  12. 49 CFR 173.27 - General requirements for transportation by aircraft.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 49 Transportation 2 2011-10-01 2011-10-01 false General requirements for transportation by aircraft. 173.27 Section 173.27 Transportation Other Regulations Relating to Transportation PIPELINE AND HAZARDOUS MATERIALS SAFETY ADMINISTRATION, DEPARTMENT OF TRANSPORTATION HAZARDOUS MATERIALS REGULATIONS SHIPPERS-GENERAL REQUIREMENTS FOR SHIPMENTS...

  13. 49 CFR 175.310 - Transportation of flammable liquid fuel; aircraft only means of transportation.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 49 Transportation 2 2013-10-01 2013-10-01 false Transportation of flammable liquid fuel; aircraft only means of transportation. 175.310 Section 175.310 Transportation Other Regulations Relating to Transportation PIPELINE AND HAZARDOUS MATERIALS SAFETY ADMINISTRATION, DEPARTMENT OF TRANSPORTATION HAZARDOUS MATERIALS REGULATIONS CARRIAGE...

  14. 49 CFR 173.172 - Aircraft hydraulic power unit fuel tank.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 49 Transportation 2 2013-10-01 2013-10-01 false Aircraft hydraulic power unit fuel tank. 173.172 Section 173.172 Transportation Other Regulations Relating to Transportation PIPELINE AND HAZARDOUS MATERIALS SAFETY ADMINISTRATION, DEPARTMENT OF TRANSPORTATION HAZARDOUS MATERIALS REGULATIONS SHIPPERS-GENERAL REQUIREMENTS FOR SHIPMENTS AND...

  15. 49 CFR 175.310 - Transportation of flammable liquid fuel; aircraft only means of transportation.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 49 Transportation 2 2010-10-01 2010-10-01 false Transportation of flammable liquid fuel; aircraft only means of transportation. 175.310 Section 175.310 Transportation Other Regulations Relating to Transportation PIPELINE AND HAZARDOUS MATERIALS SAFETY ADMINISTRATION, DEPARTMENT OF TRANSPORTATION HAZARDOUS MATERIALS REGULATIONS CARRIAGE...

  16. Aircraft electromagnetic compatibility

    NASA Technical Reports Server (NTRS)

    Clarke, Clifton A.; Larsen, William E.

    1987-01-01

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

  17. Predicting Aircraft Noise Levels

    NASA Technical Reports Server (NTRS)

    Clark, B. J.

    1983-01-01

    Computer program developed for predicting aircraft noise levels either in flight or in ground tests. Noise sources include fan inlet and exhaust jet flap (for powered lift), core (combustor), turbine and airframe. Program written in FORTRAN IV.

  18. Aircraft parameter estimation

    NASA Technical Reports Server (NTRS)

    Iliff, Kenneth W.

    1987-01-01

    The aircraft parameter estimation problem is used to illustrate the utility of parameter estimation, which applies to many engineering and scientific fields. Maximum likelihood estimation has been used to extract stability and control derivatives from flight data for many years. This paper presents some of the basic concepts of aircraft parameter estimation and briefly surveys the literature in the field. The maximum likelihood estimator is discussed, and the basic concepts of minimization and estimation are examined for a simple simulated aircraft example. The cost functions that are to be minimized during estimation are defined and discussed. Graphic representations of the cost functions are given to illustrate the minimization process. Finally, the basic concepts are generalized, and estimation from flight data is discussed. Some of the major conclusions for the simulated example are also developed for the analysis of flight data from the F-14, highly maneuverable aircraft technology (HiMAT), and space shuttle vehicles.

  19. Aircraft Engine Emissions. [conference

    NASA Technical Reports Server (NTRS)

    1977-01-01

    A conference on a aircraft engine emissions was held to present the results of recent and current work. Such diverse areas as components, controls, energy efficient engine designs, and noise and pollution reduction are discussed.

  20. Solar thermal aircraft

    DOEpatents

    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.

  1. Aircraft Safety Improvement

    NASA Technical Reports Server (NTRS)

    Kao, G.

    1985-01-01

    Fabrication and testing of honeycomb sandwich aircraft panels are discussed. Also described is the use of the following instruments: thermogravimetric analyzer, differential scanning calorimeter, limiting oxygen index, and infrared spectrometer.

  2. Aircraft electromagnetic compatibility

    NASA Astrophysics Data System (ADS)

    Clarke, Clifton A.; Larsen, William E.

    1987-06-01

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

  3. Laminar Flow Aircraft Certification

    NASA Technical Reports Server (NTRS)

    Williams, Louis J. (Compiler)

    1986-01-01

    Various topics telative to laminar flow aircraft certification are discussed. Boundary layer stability, flaps for laminar flow airfoils, computational wing design studies, manufacturing requirements, windtunnel tests, and flow visualization are among the topics covered.

  4. The Aircraft Morphing Program

    NASA Technical Reports Server (NTRS)

    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.

  5. Advanced hypersonic aircraft design

    NASA Technical Reports Server (NTRS)

    Utzinger, Rob; Blank, Hans-Joachim; Cox, Craig; Harvey, Greg; Mckee, Mike; Molnar, Dave; Nagy, Greg; Petersen, Steve

    1992-01-01

    The objective of this design project is to develop the hypersonic reconnaissance aircraft to replace the SR-71 and to complement existing intelligence gathering devices. The initial design considerations were to create a manned vehicle which could complete its mission with at least two airborne refuelings. The aircraft must travel between Mach 4 and Mach 7 at an altitude of 80,000 feet for a maximum range of 12,000 nautical miles. The vehicle should have an air breathing propulsion system at cruise. With a crew of two, the aircraft should be able to take off and land on a 10,000 foot runway, and the yearly operational costs were not to exceed $300 million. Finally, the aircraft should exhibit stealth characteristics, including a minimized radar cross-section (RCS) and a reduced sonic boom. The technology used in this vehicle should allow for production between the years 1993 and 1995.

  6. Aircraft of the future

    NASA Technical Reports Server (NTRS)

    Yeger, S.

    1985-01-01

    Some basic problems connected with attempts to increase the size and capacity of transport aircraft are discussed. According to the square-cubic law, the increase in structural weight is proportional to the third power of the increase in the linear dimensions of the aircraft when geomettric similarity is maintained, while the surface area of the aircraft increases according to the second power. A consequence is that the fraction of useful weight will decrease as aircraft increase in size. However, in flying-wing designs in which the whole load on the wing is proportional to the distribution of lifting forces, the total bending moment on the wing will be sharply reduced, enabling lighter construction. Flying wings may have an ultimate capacity of 3000 passengers.

  7. Depreciation of aircraft

    NASA Technical Reports Server (NTRS)

    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.

  8. Alternative jet aircraft fuels

    NASA Technical Reports Server (NTRS)

    Grobman, J.

    1979-01-01

    Potential changes in jet aircraft fuel specifications due to shifts in supply and quality of refinery feedstocks are discussed with emphasis on the effects these changes would have on the performance and durability of aircraft engines and fuel systems. Combustion characteristics, fuel thermal stability, and fuel pumpability at low temperature are among the factors considered. Combustor and fuel system technology needs for broad specification fuels are reviewed including prevention of fuel system fouling and fuel system technology for fuels with higher freezing points.

  9. ANALYSIS OF AIRCRAFT MOTIONS

    NASA Technical Reports Server (NTRS)

    Wingrove, R. C.

    1994-01-01

    This program was developed by Ames Research Center, in cooperation with the National Transportation Safety Board, as a technique for deriving time histories of an aircraft's motion from Air Traffic Control (ATC) radar records. This technique uses the radar range and azimuth data, along with the downlinked altitude data, to derive an expanded set of data which includes airspeed, lift, attitude angles (pitch, roll, and heading), etc. This technique should prove useful as a source of data in the investigation of commercial airline accidents and in the analysis of accidents involving aircraft which do not have onboard data recorders (e.g., military, short-haul, and general aviation). The technique used to determine the aircraft motions involves smoothing of raw radar data. These smoothed results, in combination with other available information (wind profiles and aircraft performance data), are used to derive the expanded set of data. This program uses a cubic least-square fit to smooth the raw data. This moving-arc procedure provides a smoothed time history of the aircraft position, the inertial velocities, and accelerations. Using known winds, these inertial data are transformed to aircraft stability axes to provide true airspeed, thrust-drag, lift, and roll angle. Further derivation, based on aircraft dependent performance data, can determine the aircraft angle of attack, pitch, and heading angle. Results of experimental tests indicate that values derived from ATC radar records using this technique agree favorably with airborne measurements. This program is written in FORTRAN IV to be executed in the batch mode, and has been implemented on a CDC 6000 series computer with a central memory requirement of 64k (octal) of 60 bit words.

  10. 49 CFR 175.26 - Notification at cargo facilities of hazardous materials requirements.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... aircraft must be offered in accordance with the Federal Hazardous Materials Regulations (49 CFR parts 171... accepted outside of the United States, in the language of the host country; and (2) On a background...

  11. 49 CFR 175.26 - Notification at cargo facilities of hazardous materials requirements.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... aircraft must be offered in accordance with the Federal Hazardous Materials Regulations (49 CFR parts 171... contrasting color. (c) Size and color of the notice are optional. Additional information, examples,...

  12. 49 CFR 175.26 - Notification at cargo facilities of hazardous materials requirements.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... aircraft must be offered in accordance with the Federal Hazardous Materials Regulations (49 CFR parts 171... contrasting color. (c) Size and color of the notice are optional. Additional information, examples,...

  13. Concussions Strike 1 in 3 Water Polo Players

    MedlinePlus

    ... fullstory_159634.html Concussions Strike 1 in 3 Water Polo Players Average was just over 2 per ... 2016 WEDNESDAY, June 29, 2016 (HealthDay News) -- Add water polo to the list of sports where concussions ...

  14. Pathognomonic symptom associated with lightning strike: Lichtenberg figure.

    PubMed

    Yigit, Mehmet; Tanrikulu, Nazmiye; Turkdogan, Kenan Ahmet; Yigit, Eda

    2015-02-01

    Lightning strikes especially occur during spring and summer months in the afternoons when there is heavy rain. In deaths resulting from lightning strike, there may either be no evidence on the dead person's clothes or body, or there may be burnt or torn patches on their clothes and lichtenberg figures specific to lightning strikes on their bodies. In such cases that also have a comorbid of cognitive dysfunction, since there is generally amnesia, having these figures during the physical examination has a valuable place in early diagnosis and quick treatment. This paper presents a case of lightning strike that was found to have Lichtenberg figures on the back and right leg after secondary examination. PMID:25842563

  15. Striking nurses and midwives stand united against Hunt's pay freeze.

    PubMed

    Keogh, Kat; Kleebauer, Alistair

    2014-10-21

    Thousands of nurses and midwives in England and Northern Ireland went on strike in protest at the government's decision to deny 70 per cent of NHS nurses a 1 per cent cost of living pay rise. PMID:25315523

  16. Measurements of lightning rod responses to nearby strikes

    NASA Astrophysics Data System (ADS)

    Moore, C. B.; Aulich, G. D.; Rison, W.

    2000-05-01

    Following Benjamin Franklin's invention of the lightning rod, based on his discovery that electrified objects could be discharged by approaching them with a metal needle in hand, conventional lightning rods in the U.S. have had sharp tips. In recent years, the role of the sharp tip in causing a lightning rod to act as a strike receptor has been questioned leading to experiments in which pairs of various sharp-tipped and blunt rods have been exposed beneath thunderclouds to determine the better strike receptor. After seven years of tests, none of the sharp Franklin rods or of the so-called “early streamer emitters” has been struck, but 12 blunt rods with tip diameters ranging from 12.7 mm to 25.4 mm have taken strikes. Our field experiments and our analyses indicate that the strike-reception probabilities of Franklin's rods are greatly increased when their tips are made moderately blunt.

  17. Inferential Model Criticism of the "Empire Strikes Back."

    ERIC Educational Resources Information Center

    Frentz, Thomas F.; Hale, Mary E.

    1983-01-01

    Describes a method of rhetorical criticism to be used in situations where the values of critic and audience differ in significant ways. Uses the method to analyze the responses of children to "The Empire Strikes Back." (PD)

  18. Why You Can Expect Fewer Teacher Strikes This Year

    ERIC Educational Resources Information Center

    American School Board Journal, 1975

    1975-01-01

    The National Education Association and the American Federation of Teachers are facing three realities that might make them reluctant to strike: an army of unemployed teachers, an internecine battle, and a rotten economy. (Author/IRT)

  19. Depression Strikes, Stays with Many Caregivers of Critically Ill

    MedlinePlus

    ... nlm.nih.gov/medlineplus/news/fullstory_158780.html Depression Strikes, Stays With Many Caregivers of Critically Ill ... News) -- Caregivers for the critically ill often suffer depression that lingers long after their loved one's hospital ...

  20. 33. SOUTH, PIER IV, DRAW REST SUPPORT, END LOCK STRIKE ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    33. SOUTH, PIER IV, DRAW REST SUPPORT, END LOCK STRIKE AND JACK PAD. OPEN END OF SHORE BOX. - Burlington Northern Railroad Bridge, Spanning Willamette River at River Mile 6.9, Portland, Multnomah County, OR

  1. Concussions Strike 1 in 3 Water Polo Players

    MedlinePlus

    ... medlineplus.gov/news/fullstory_159634.html Concussions Strike 1 in 3 Water Polo Players Average was just ... are common. A recent survey of more than 1,500 USA Water Polo members found 36 percent ...

  2. Cancer Strikes Out!/Definitions/ Glossary/ Common Types

    MedlinePlus

    ... Cover Story: Leukemia/Lymphoma Cancer Strikes Out!/ Definitions/ Glossary/ Common Types Past Issues / Summer 2008 Table of ... stage and the type of cancer. Leukemia-Lymphoma Glossary B-cell: A white blood cell that comes ...

  3. NASA Hazard Analysis Process

    NASA Technical Reports Server (NTRS)

    Deckert, George

    2010-01-01

    This viewgraph presentation reviews The NASA Hazard Analysis process. The contents include: 1) Significant Incidents and Close Calls in Human Spaceflight; 2) Subsystem Safety Engineering Through the Project Life Cycle; 3) The Risk Informed Design Process; 4) Types of NASA Hazard Analysis; 5) Preliminary Hazard Analysis (PHA); 6) Hazard Analysis Process; 7) Identify Hazardous Conditions; 8) Consider All Interfaces; 9) Work a Preliminary Hazard List; 10) NASA Generic Hazards List; and 11) Final Thoughts

  4. Optimization of stability index versus first strike cost

    SciTech Connect

    Canavan, G.H.

    1997-05-01

    This note studies the impact of maximizing the stability index rather than minimizing the first strike cost in choosing offensive missile allocations. It does so in the context of a model in which exchanges between vulnerable missile forces are modeled probabilistically, converted into first and second strike costs through approximations to the value target sets at risk, and the stability index is taken to be their ratio. The value of the allocation that minimizes the first strike cost for both attack preferences are derived analytically. The former recovers results derived earlier. The latter leads to an optimum at unity allocation for which the stability index is determined analytically. For values of the attack preference greater than about unity, maximizing the stability index increases the cost of striking first 10--15%. For smaller values of the attack preference, maximizing the index increases the second strike cost a similar amount. Both are stabilizing, so if both sides could be trusted to target on missiles in order to minimize damage to value and maximize stability, the stability index for vulnerable missiles could be increased by about 15%. However, that would increase the cost to the first striker by about 15%. It is unclear why--having decided to strike--he would do so in a way that would increase damage to himself.

  5. The influence of striking object characteristics on the impact energy.

    PubMed

    Sprenger, Florian D; Siegenthaler, Lea; Kneubuehl, Beat P; Jackowski, Christian

    2016-05-01

    A common form of violence investigated in legal medicine is blunt trauma caused by striking with different objects. The injuries and medical consequences have been widely examined, whereas the forces and especially the energies acting on impact have rarely been analyzed. This study focuses on how the impact energy of different striking objects depends on their characteristics. A total of 1170 measurements of horizontal strikes against a static and relatively heavy pendulum have been acquired with 13 volunteers. The main focus was laid on how the weight, the length, and the center of mass of the different striking objects influenced the striking energy. The results show average impact energies in the range of 67.3 up to 311.5 J for men with an optimum weight of about 1.3 kg with its center of mass in the far end quarter for a 1-m-long striking object. The average values for women range from 30 to 202.6 J, with an optimum weight between 1.65 and 2.2 kg and similar settings for the center of mass as the men. Also, the impact energies are getting higher with shorter object lengths and reach a maximum at a length of about 0.3 to 0.4 m. The male volunteers' impact energy was on average by 84.2% higher than the values of the female volunteers, where the impact masses were very similar and the impact velocities played the key role. PMID:26449359

  6. Composite-fiber hazards. Final report

    SciTech Connect

    Seibert, J.F.

    1990-12-01

    This report reviews potential health hazards from carbon/graphite and boron composite materials used in aircraft. Carbon and boron fibers are used as reinforcement in an epoxy matrix to form composite material aircraft parts. There is increasing concern over the potential health effects of these fibers released during sanding and grinding of composite parts in structural repair shops, and during clean up operations following aircraft accidents involving fire and/or breakage of composite parts. With the demise of the term 'CORKER,' hazards from carbon composite materials were deemphasized. However, the CORKER annotation only addressed the electrical shorting hazards from airborne fibers following a fire and did not examine in detail potential health effects. Maintenance workers fear that carbon fibers are carcinogens. A review of the current literature on carbon fiber indicates it is relatively inert. Industrial hygiene evaluations should include sampling for total dust and comparing the levels to the ACGIH TLV for nuisance dust. Occupational health efforts should focus on problems with contact dermatitis from the resins systems and toxic effects of resin hardeners.

  7. 150 Passenger Commercial Aircraft

    NASA Technical Reports Server (NTRS)

    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

  8. Approach to the assessment of the hazard. [fire released carbon fiber electrical effects

    NASA Technical Reports Server (NTRS)

    Huston, R. J.

    1980-01-01

    An overview of the carbon fiber hazard assessment is presented. The potential risk to the civil sector associated with the accidental release of carbon fibers from aircraft having composite structures was assessed along with the need for protection of civil aircraft from carbon fibers.

  9. New methods and results for quantification of lightning-aircraft electrodynamics

    NASA Technical Reports Server (NTRS)

    Pitts, Felix L.; Lee, Larry D.; Perala, Rodney A.; Rudolph, Terence H.

    1987-01-01

    The NASA F-106 collected data on the rates of change of electromagnetic parameters on the aircraft surface during over 700 direct lightning strikes while penetrating thunderstorms at altitudes from 15,000 t0 40,000 ft (4,570 to 12,190 m). These in situ measurements provided the basis for the first statistical quantification of the lightning electromagnetic threat to aircraft appropriate for determining indirect lightning effects on aircraft. These data are used to update previous lightning criteria and standards developed over the years from ground-based measurements. The proposed standards will be the first which reflect actual aircraft responses measured at flight altitudes. Nonparametric maximum likelihood estimates of the distribution of the peak electromagnetic rates of change for consideration in the new standards are obtained based on peak recorder data for multiple-strike flights. The linear and nonlinear modeling techniques developed provide means to interpret and understand the direct-strike electromagnetic data acquired on the F-106. The reasonable results obtained with the models, compared with measured responses, provide increased confidence that the models may be credibly applied to other aircraft.

  10. Volcano instability induced by strike-slip faulting

    NASA Astrophysics Data System (ADS)

    Lagmay, A. M. F.; van Wyk de Vries, B.; Kerle, N.; Pyle, D. M.

    2000-09-01

    Analogue sand cone experiments were conducted to study instability generated on volcanic cones by basal strike-slip movement. The results of the analogue models demonstrate that edifice instability may be generated when strike-slip faults underlying a volcano move as a result of tectonic adjustment. This instability occurs on flanks of the volcano above the strike-slip shear. On the surface of the volcano this appears as a pair of sigmoids composed of one reverse and one normal fault. In the interior of the cone the faults form a flower structure. Two destabilised regions are created on the cone flanks between the traces of the sigmoidal faults. Bulging, intense fracturing and landsliding characterise these unstable flanks. Additional analogue experiments conducted to model magmatic intrusion show that fractures and faults developed within the volcanic cone due to basal strike-slip motions strongly control the path of the intruding magma. Intrusion is diverted towards the areas where previous development of reverse and normal faults have occurred, thus causing further instability. We compare our model results to two examples of volcanoes on strike-slip faults: Iriga volcano (Philippines), which underwent non-magmatic collapse, and Mount St. Helens (USA), where a cryptodome was emplaced prior to failure. In the analogue and natural examples, the direction of collapse takes place roughly parallel to the orientation of the underlying shear. The model presented proposes one mechanism for strike-parallel breaching of volcanoes, recently recognised as a common failure direction of volcanoes found in regions with transcurrent and transtensional deformation. The recognition of the effect of basal shearing on volcano stability enables prediction of the likely direction of eventual flank failure in volcanoes overlying strike-slip faults.

  11. Pathfinder Aircraft in Flight

    NASA Technical Reports Server (NTRS)

    1995-01-01

    The Pathfinder research aircraft's wing structure was clearly defined as it soared under a clear blue sky during a test flight July 27, 1995, from Dryden Flight Research Center, Edwards, California. The center section and outer wing panels of the aircraft had ribs constructed of thin plastic foam, while the ribs in the inner wing panels are fabricated from lightweight composite material. Developed by AeroVironment, Inc., the Pathfinder was one of several unmanned aircraft being evaluated under NASA's Environmental Research Aircraft and Sensor Technology (ERAST) program. Pathfinder was a lightweight, solar-powered, remotely piloted flying wing aircraft used to demonstrate the use of solar power for long- duration, high-altitude flight. Its name denotes its mission as the 'Pathfinder' or first in a series of solar-powered aircraft that will be able to remain airborne for weeks or months on scientific sampling and imaging missions. Solar arrays covered most of the upper wing surface of the Pathfinder aircraft. These arrays provided up to 8,000 watts of power at high noon on a clear summer day. That power fed the aircraft's six electric motors as well as its avionics, communications, and other electrical systems. Pathfinder also had a backup battery system that could provide power for two to five hours, allowing for limited-duration flight after dark. Pathfinder flew at airspeeds of only 15 to 20 mph. Pitch control was maintained by using tiny elevators on the trailing edge of the wing while turns and yaw control were accomplished by slowing down or speeding up the motors on the outboard sections of the wing. On September 11, 1995, Pathfinder set a new altitude record for solar- powered aircraft of 50,567 feet above Edwards Air Force Base, California, on a 12-hour flight. On July 7, 1997, it set another, unofficial record of 71,500 feet at the Pacific Missile Range Facility, Kauai, Hawaii. In 1998, Pathfinder was modified into the longer-winged Pathfinder Plus

  12. Pathfinder aircraft in flight

    NASA Technical Reports Server (NTRS)

    1995-01-01

    The Pathfinder research aircraft's wing structure was clearly defined as it soared under a clear blue sky during a test flight July 27, 1995, from Dryden Flight Research Center, Edwards, California. The center section and outer wing panels of the aircraft had ribs constructed of thin plastic foam, while the ribs in the inner wing panels are fabricated from lightweight composite material. Developed by AeroVironment, Inc., the Pathfinder was one of several unmanned aircraft being evaluated under NASA's Environmental Research Aircraft and Sensor Technology (ERAST) program. Pathfinder was a lightweight, solar-powered, remotely piloted flying wing aircraft used to demonstrate the use of solar power for long-duration, high-altitude flight. Its name denotes its mission as the 'Pathfinder' or first in a series of solar-powered aircraft that will be able to remain airborne for weeks or months on scientific sampling and imaging missions. Solar arrays covered most of the upper wing surface of the Pathfinder aircraft. These arrays provided up to 8,000 watts of power at high noon on a clear summer day. That power fed the aircraft's six electric motors as well as its avionics, communications, and other electrical systems. Pathfinder also had a backup battery system that could provide power for two to five hours, allowing for limited-duration flight after dark. Pathfinder flew at airspeeds of only 15 to 20 mph. Pitch control was maintained by using tiny elevators on the trailing edge of the wing while turns and yaw control were accomplished by slowing down or speeding up the motors on the outboard sections of the wing. On September 11, 1995, Pathfinder set a new altitude record for solar-powered aircraft of 50,567 feet above Edwards Air Force Base, California, on a 12-hour flight. On July 7, 1997, it set another, unofficial record of 71,500 feet at the Pacific Missile Range Facility, Kauai, Hawaii. In 1998, Pathfinder was modified into the longer-winged Pathfinder Plus

  13. Typhoon hazards in the Shanghai area.

    PubMed

    Zong, Y; Chen, X

    1999-03-01

    There are three major typhoon hazards that apply to the Shanghai area. First, galeforce winds can damage buildings and service facilities. The most severe damage from this occurs only when a typhoon strikes Shanghai directly. Second, both the urban and rural sections of Shanghai are liable to flooding during typhoon seasons. These floods occur when typhoon-induced storm surges coincide with high spring tides and meet with high discharges from the river network as a result of the typhoon downpours. Third, typhoon-induced torrential rain has caused waterlog hazards, particularly in the most densely populated parts of Shanghai. The waterlog hazard has been exacerbated by land subsidence and poor management of pumping systems. In order to prevent disasters happening and reduce the scale of damage, the government has issued construction guidelines and invested in flood defences. Further measures are to be brought in including engineering projects, educational programmes and insurance policies. PMID:10204288

  14. Aircraft noise synthesis system

    NASA Technical Reports Server (NTRS)

    Mccurdy, David A.; Grandle, Robert E.

    1987-01-01

    A second-generation Aircraft Noise Synthesis System has been developed to provide test stimuli for studies of community annoyance to aircraft flyover noise. The computer-based system generates realistic, time-varying, audio simulations of aircraft flyover noise at a specified observer location on the ground. The synthesis takes into account the time-varying aircraft position relative to the observer; specified reference spectra consisting of broadband, narrowband, and pure-tone components; directivity patterns; Doppler shift; atmospheric effects; and ground effects. These parameters can be specified and controlled in such a way as to generate stimuli in which certain noise characteristics, such as duration or tonal content, are independently varied, while the remaining characteristics, such as broadband content, are held constant. The system can also generate simulations of the predicted noise characteristics of future aircraft. A description of the synthesis system and a discussion of the algorithms and methods used to generate the simulations are provided. An appendix describing the input data and providing user instructions is also included.

  15. High altitude reconnaissance aircraft

    NASA Technical Reports Server (NTRS)

    Yazdo, Renee Anna; Moller, David

    1990-01-01

    At the equator the ozone layer ranges from 65,000 to 130,000 plus feet, which is beyond the capabilities of the ER-2, NASA's current high altitude reconnaissance aircraft. The Universities Space Research Association, in cooperation with NASA, is sponsoring an undergraduate program which is geared to designing an aircraft that can study the ozone layer at the equator. This aircraft must be able to cruise at 130,000 feet for six hours at Mach 0.7, while carrying 3,000 lbs. of payload. In addition, the aircraft must have a minimum range of 6,000 miles. In consideration of the novel nature of this project, the pilot must be able to take control in the event of unforeseen difficulties. Three aircraft configurations were determined to be the most suitable - a joined-wing, a biplane, and a twin-boom conventional airplane. The performance of each configuration was analyzed to investigate the feasibility of the project.

  16. Aircraft Operations Classification System

    NASA Technical Reports Server (NTRS)

    Harlow, Charles; Zhu, Weihong

    2001-01-01

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

  17. Aircraft control position indicator

    NASA Technical Reports Server (NTRS)

    Dennis, Dale V. (Inventor)

    1987-01-01

    An aircraft control position indicator was provided that displayed the degree of deflection of the primary flight control surfaces and the manner in which the aircraft responded. The display included a vertical elevator dot/bar graph meter display for indication whether the aircraft will pitch up or down, a horizontal aileron dot/bar graph meter display for indicating whether the aircraft will roll to the left or to the right, and a horizontal dot/bar graph meter display for indicating whether the aircraft will turn left or right. The vertical and horizontal display or displays intersect to form an up/down, left/right type display. Internal electronic display driver means received signals from transducers measuring the control surface deflections and determined the position of the meter indicators on each dot/bar graph meter display. The device allows readability at a glance, easy visual perception in sunlight or shade, near-zero lag in displaying flight control position, and is not affected by gravitational or centrifugal forces.

  18. Health Hazard Evaluations

    MedlinePlus

    ... Products Programs Contact NIOSH HHE Media Health Hazard Evaluations (HHEs) Language: English en Español Recommend on Facebook ... or employers can ask the NIOSH Health Hazard Evaluation (HHE) Program to help learn whether health hazards ...

  19. Action on Hazardous Wastes.

    ERIC Educational Resources Information Center

    EPA Journal, 1979

    1979-01-01

    U.S. EPA is gearing up to investigate about 300 hazardous waste dump sites per year that could pose an imminent health hazard. Prosecutions are expected to result from the priority effort at investigating illegal hazardous waste disposal. (RE)

  20. Damage tolerance for commuter aircraft

    NASA Technical Reports Server (NTRS)

    Lincoln, John W.

    1992-01-01

    The damage tolerance experience in the United States Air Force with military aircraft and in the commercial world with large transport category aircraft indicates that a similar success could be achieved in commuter aircraft. The damage tolerance process is described for the purpose of defining the approach that could be used for these aircraft to ensure structural integrity. Results of some of the damage tolerance assessments for this class of aircraft are examined to illustrate the benefits derived from this approach. Recommendations are given for future damage tolerance assessment of existing commuter aircraft and on the incorporation of damage tolerance capability in new designs.

  1. Metabarcoding avian diets at airports: implications for birdstrike hazard management planning

    PubMed Central

    2013-01-01

    Background Wildlife collisions with aircraft cost the airline industry billions of dollars per annum and represent a public safety risk. Clearly, adapting aerodrome habitats to become less attractive to hazardous wildlife will reduce the incidence of collisions. Formulating effective habitat management strategies relies on accurate species identification of high-risk species. This can be successfully achieved for all strikes either through morphology and/or DNA-based identifications. Beyond species identification, dietary analysis of birdstrike gut contents can provide valuable intelligence for airport hazard management practices in regards to what food is attracting which species to aerodromes. Here, we present birdstrike identification and dietary data from Perth Airport, Western Australia, an aerodrome that saw approximately 140,000 aircraft movements in 2012. Next-generation high throughput DNA sequencing was employed to investigate 77 carcasses from 16 bird species collected over a 12-month period. Five DNA markers, which broadly characterize vertebrates, invertebrates and plants, were used to target three animal mitochondrial genes (12S rRNA, 16S rRNA, and COI) and a plastid gene (trnL) from DNA extracted from birdstrike carcass gastrointestinal tracts. Results Over 151,000 DNA sequences were generated, filtered and analyzed by a fusion-tag amplicon sequencing approach. Across the 77 carcasses, the most commonly identified vertebrate was Mus musculus (house mouse). Acrididae (grasshoppers) was the most common invertebrate family identified, and Poaceae (grasses) the most commonly identified plant family. The DNA-based dietary data has the potential to provide some key insights into feeding ecologies within and around the aerodrome. Conclusions The data generated here, together with the methodological approach, will greatly assist in the development of hazard management plans and, in combination with existing observational studies, provide an improved way to

  2. Aircraft icing instrumentation: Unfilled needs. [rotary wing aircraft

    NASA Technical Reports Server (NTRS)

    Kitchens, P. F.

    1980-01-01

    A list of icing instrumentation requirements are presented. Because of the Army's helicopter orientation, many of the suggestions are specific to rotary wing aircraft; however, some of the instrumentation are also suitable for general aviation aircraft.

  3. Isolated Sensorineural Hearing Loss as a Sequela after Lightning Strike.

    PubMed

    Turan, Mahfuz; Kalkan, Ferhat; Bozan, Nazım; Özçalimli, İsa; Zeki Erdem, Mehmet; Yalınkılıç, Abdülaziz; Garca, Mehmet Fatih

    2015-01-01

    In most of the surviving patients after a lightning strike, audiovestibular abnormalities have been reported. The most frequently reported type of abnormalities is a tympanic membrane perforation with hearing loss and external ear canal burn. However a sensor neural hearing loss and mixed type hearing loss can also occur, but these occur rarely. A nineteen-year-old female patient had, after a lightning strike, serious burns on the left ear, behind the ear, and on the chest and neck. She also had in her left ear 108 dB hearing loss with irregular central perforation and in her right ear 52 dB sensorineural hearing loss. There was no hearing loss before the strike. A hearing aid was recommended for the right ear and good care and follow-up were recommended for the left ear. A lightning strike can cause serious audiological damage. Therefore, it is necessary to make a careful audiovestibular evaluation of the patients. Although there exist rarely healed cases from sensorineural hearing loss after lightning strike in literature, in our case hearing loss occurred bilaterally and then it healed unilaterally. This condition is quite rare in literature. PMID:26161278

  4. How Orogen-scale Exhumed Strike-slip Faults Initiate

    NASA Astrophysics Data System (ADS)

    Cao, S.; Neubauer, F.

    2015-12-01

    Orogen-scale strike-slip faults present one the most important geodynamic processes affecting the lithosphere-asthenosphere system. In specific subtypes, faulting is virtually initiated along hot-to-cool boundaries, e.g. at such of hot granite intrusions or metamorphic core complexes to cool country rocks. Such fault zones are often subparallel to mountain ranges and expose a wide variety of mylonitic, cataclastic and non-cohesive fault rocks, which were formed at different structural levels of the crust and are stacked within each other ("telescoping"). Exhumation of rocks is, therefore, a common feature of such strike-slip faults implying major transtensive and/or transpressive processes accompanying pure strike-slip motion. The hot-to-cool thermal structure across the fault zone significantly influences the physical fault rock properties. One major question is how and where a major strike-slip initiates and further development. Here, we propose a model in which major continental exhumed strike-slip faults potentially evolve along rheologically weak zones such as plutons or margins of metamorphic complexes. As an example, we propose a model for the Ailao Shan-Red River (ASRR) fault, SE Asia, which initiated along the edge of a plutonic belt and evolved in response to India-Asia collision with four tectonic phases.

  5. Relation between inflammables and ignition sources in aircraft environments

    NASA Technical Reports Server (NTRS)

    Scull, Wilfred E

    1951-01-01

    A literature survey was conducted to determine the relation between aircraft ignition sources and inflammables. Available literature applicable to the problem of aircraft fire hazards is analyzed and discussed. Data pertaining to the effect of many variables on ignition temperatures, minimum ignition pressures, minimum spark-ignition energies of inflammables, quenching distances of electrode configurations, and size of openings through which flame will not propagate are presented and discussed. Ignition temperatures and limits of inflammability of gasoline in air in different test environments, and the minimum ignition pressures and minimum size of opening for flame propagation in gasoline-air mixtures are included; inerting of gasoline-air mixtures is discussed.

  6. Relation Between Inflammables and Ignition Sources in Aircraft Environments

    NASA Technical Reports Server (NTRS)

    Scull, Wilfred E

    1950-01-01

    A literature survey was conducted to determine the relation between aircraft ignition sources and inflammables. Available literature applicable to the problem of aircraft fire hazards is analyzed and, discussed herein. Data pertaining to the effect of many variables on ignition temperatures, minimum ignition pressures, and minimum spark-ignition energies of inflammables, quenching distances of electrode configurations, and size of openings incapable of flame propagation are presented and discussed. The ignition temperatures and the limits of inflammability of gasoline in air in different test environments, and the minimum ignition pressure and the minimum size of openings for flame propagation of gasoline - air mixtures are included. Inerting of gasoline - air mixtures is discussed.

  7. Flight-deck display of neighboring aircraft wake vortices

    NASA Astrophysics Data System (ADS)

    Holforty, Wendy L.

    Over the coming decades, aviation operations are predicted to rise steadily, increasing the burden on already congested and constrained airspace. A major factor governing the safe minimum separation distance between aircraft is the hazard generated by the wake of neighboring aircraft. Unaware of their proximity to other traffic, aircraft have encountered the wake turbulence of neighboring aircraft tens of miles ahead of them with serious or fatal consequences. The wake display described herein is a perspective view, synthetic vision, flight deck display that enables flight crews to "see" neighboring aircraft, as well as their wakes via a predictive algorithm. Capable of enhancing the situational awareness with respect to the wake-vortex encounter hazard by enabling the flight crew to see the relative position of their aircraft with respect to the wake hazard, the display may allow for a decrease in the standard aircraft spacing to those now used in VFR conditions and an increase in airport and airspace capacity. At present, there is no mechanism in place in the National Airspace System that warns pilots of potential wake vortex encounters. The concept of a wake vortex display addresses the need for a real-time wake vortex avoidance scheme available directly to the pilot. The wake display has been evaluated under both simulated and actual flight conditions. Thirteen pilots with flight experience ranging from a student pilot to commercial airline and military pilots served as pilot test subjects evaluating the display under simulated conditions. The pilot test subjects completed a survey concerning their knowledge and understanding of wake vortices prior to the simulation data trials and, after the trials, they completed a pilot evaluation and postflight survey rating their experience and providing feedback for the display design. One test pilot and four guest pilots flew the display during the in-flight evaluations incorporating three wake encounter scenarios. They

  8. Birds and Aircraft on Midway Islands, 1956-57 Investigations

    USGS Publications Warehouse

    Kenyon, K.W.; Rice, D.W.; Robbins, C.S.; Aldrich, J.W.

    1958-01-01

    The purpose of this study is to determine the extent to which certain species of birds contribute to the hazard to aircraft at Midway; to learn more about the population dynamics and habits of these species to determine what type of control measures might be possible without endangering the species; and to test methods of control which are suggested. Most of the study has been devoted to the two species of albatrosses and the sooty terns nesting at Midway because of the current belief that these species offered the greatest danger to aircraft safety.

  9. Volcanic ash - danger to aircraft in the north Pacific

    USGS Publications Warehouse

    Neal, Christina A.; Casadevall, Thomas J.; Miller, Thomas P.; Hendley, James W., II; Stauffer, Peter H.

    1997-01-01

    The world's busy air traffic corridors pass over hundreds of volcanoes capable of sudden, explosive eruptions. In the United States alone, aircraft carry many thousands of passengers and millions of dollars of cargo over volcanoes each day. Volcanic ash can be a serious hazard to aviation even thousands of miles from an eruption. Airborne ash can diminish visibility, damage flight control systems, and cause jet engines to fail. USGS and other scientists with the Alaska Volcano Observatory are playing a leading role in the international effort to reduce the risk posed to aircraft by volcanic eruptions.

  10. Emissions from queuing aircraft

    SciTech Connect

    Segal, H.

    1980-01-01

    The ability of the FAA (U.S. Federal Aviation Administration) Simplex mathematical model, which employs a simple point-source algorithm with provisions for selecting a particular plume height and initial box size for each aircraft being analyzed, to predict air quality through modeling emissions released from queuing aircraft was verified by measurements of carbon monoxide emissions from such aircraft during a five-day period at Los Angeles International Airport. The model predicted carbon monoxide concentrations of 4 ppm (National Ambient Air Quality Standard limit value is 35 ppm) at expected populated locations during the highest activity hour monitored. This study should also apply to other engine exhaust gases such as NO/sub x/.

  11. Transport aircraft accident dynamics

    NASA Technical Reports Server (NTRS)

    Cominsky, A.

    1982-01-01

    A study was carried out of 112 impact survivable jet transport aircraft accidents (world wide) of 27,700 kg (60,000 lb.) aircraft and up extending over the last 20 years. This study centered on the effect of impact and the follow-on events on aircraft structures and was confined to the approach, landing and takeoff segments of the flight. The significant characteristics, frequency of occurrence and the effect on the occupants of the above data base were studied and categorized with a view to establishing typical impact scenarios for use as a basis of verifying the effectiveness of potential safety concepts. Studies were also carried out of related subjects such as: (1) assessment of advanced materials; (2) human tolerance to impact; (3) merit functions for safety concepts; and (4) impact analysis and test methods.

  12. Scaling aircraft noise perception.

    NASA Technical Reports Server (NTRS)

    Ollerhead, J. B.

    1973-01-01

    Following a brief review of the background to the study, an extensive experiment is described which was undertaken to assess the practical differences between numerous alternative methods for calculating the perceived levels of individual aircraft flyover wounds. One hundred and twenty recorded sounds, including jets, turboprops, piston aircraft and helicopters were rated by a panel of subjects in a pair comparison test. The results were analyzed to evaluate a number of noise rating procedures, in terms of their ability to accurately estimate both relative and absolute perceived noise levels over a wider dynamic range (84-115 dB SPL) than had generally been used in previous experiments. Performances of the different scales were examined in detail for different aircraft categories, and the merits of different band level summation procedures, frequency weighting functions, duration and tone corrections were investigated.

  13. Alternative aircraft fuels technology

    NASA Technical Reports Server (NTRS)

    Grobman, J.

    1976-01-01

    NASA is studying the characteristics of future aircraft fuels produced from either petroleum or nonpetroleum sources such as oil shale or coal. These future hydrocarbon based fuels may have chemical and physical properties that are different from present aviation turbine fuels. This research is aimed at determining what those characteristics may be, how present aircraft and engine components and materials would be affected by fuel specification changes, and what changes in both aircraft and engine design would be required to utilize these future fuels without sacrificing performance, reliability, or safety. This fuels technology program was organized to include both in-house and contract research on the synthesis and characterization of fuels, component evaluations of combustors, turbines, and fuel systems, and, eventually, full-scale engine demonstrations. A review of the various elements of the program and significant results obtained so far are presented.

  14. Pathfinder aircraft in flight

    NASA Technical Reports Server (NTRS)

    1996-01-01

    The unique Pathfinder solar-powered flying wing, is shown during a checkout flight from the Dryden Flight Research Center, Edwards, California. This two-hour low-altitude flight over Rogers Dry Lake, Nov. 19, 1996, served to test aircraft systems and functional procedures, according to officials of AeroVironment, Inc., Pathfinder's developer and operator. Pathfinder was a lightweight, solar-powered, remotely piloted flying wing aircraft used to demonstrate the use of solar power for long-duration, high-altitude flight. Its name denotes its mission as the 'Pathfinder' or first in a series of solar-powered aircraft that will be able to remain airborne for weeks or months on scientific sampling and imaging missions. Solar arrays covered most of the upper wing surface of the Pathfinder aircraft. These arrays provided up to 8,000 watts of power at high noon on a clear summer day. That power fed the aircraft's six electric motors as well as its avionics, communications, and other electrical systems. Pathfinder also had a backup battery system that could provide power for two to five hours, allowing for limited-duration flight after dark. Pathfinder flew at airspeeds of only 15 to 20 mph. Pitch control was maintained by using tiny elevators on the trailing edge of the wing while turns and yaw control were accomplished by slowing down or speeding up the motors on the outboard sections of the wing. On September 11, 1995, Pathfinder set a new altitude record for solar-powered aircraft of 50,567 feet above Edwards Air Force Base, California, on a 12-hour flight. On July 7, 1997, it set another, unofficial record of 71,500 feet at the Pacific Missile Range Facility, Kauai, Hawaii. In 1998, Pathfinder was modified into the longer-winged Pathfinder Plus configuration. (See the Pathfinder Plus photos and project description.)

  15. Pathfinder aircraft flight

    NASA Technical Reports Server (NTRS)

    1996-01-01

    The Pathfinder research aircraft's wing structure is clearly defined as it soars under a clear blue sky during a test flight from Dryden Flight Research Center, Edwards, California, in November of 1996. Pathfinder was a lightweight, solar-powered, remotely piloted flying wing aircraft used to demonstrate the use of solar power for long-duration, high-altitude flight. Its name denotes its mission as the 'Pathfinder' or first in a series of solar-powered aircraft that will be able to remain airborne for weeks or months on scientific sampling and imaging missions. Solar arrays covered most of the upper wing surface of the Pathfinder aircraft. These arrays provided up to 8,000 watts of power at high noon on a clear summer day. That power fed the aircraft's six electric motors as well as its avionics, communications, and other electrical systems. Pathfinder also had a backup battery system that could provide power for two to five hours, allowing for limited-duration flight after dark. Pathfinder flew at airspeeds of only 15 to 20 mph. Pitch control was maintained by using tiny elevators on the trailing edge of the wing while turns and yaw control were accomplished by slowing down or speeding up the motors on the outboard sections of the wing. On September 11, 1995, Pathfinder set a new altitude record for solar-powered aircraft of 50,567 feet above Edwards Air Force Base, California, on a 12-hour flight. On July 7, 1997, it set another, unofficial record of 71,500 feet at the Pacific Missile Range Facility, Kauai, Hawaii. In 1998, Pathfinder was modified into the longer-winged Pathfinder Plus configuration. (See the Pathfinder Plus photos and project description.)

  16. Aircraft surface coatings

    NASA Technical Reports Server (NTRS)

    1982-01-01

    Liquid, spray on elastomeric polyurethanes are selected and investigated as best candidates for aircraft external protective coatings. Flight tests are conducted to measure drag effects of these coatings compared to paints and a bare metal surface. The durability of two elastometric polyurethanes are assessed in airline flight service evaluations. Laboratory tests are performed to determine corrosion protection properties, compatibility with aircraft thermal anti-icing systems, the effect of coating thickness on erosion durability, and the erosion characteristics of composite leading edges-bare and coated. A cost and benefits assessment is made to determine the economic value of various coating configurations to the airlines.

  17. Aircraft Flutter Testing

    NASA Technical Reports Server (NTRS)

    1997-01-01

    Wilmer Reed gained international recognition for his innovative research, contributions and patented ideas relating to flutter and aeroelasticity of aerospace vehicles at Langley Research Center. In the early 1980's, Reed retired from Langley and joined the engineering staff of Dynamic Engineering Inc. While at DEI, Reed conceived and patented the DEI Flutter Exciter, now used world-wide in flight flutter testing of new or modified aircraft designs. When activated, the DEI Flutter Exciter alternately deflects the airstream upward and downward in a rapid manner, creating a force similar to that produced by an oscillating trailing edge flap. The DEI Flutter Exciter is readily adaptable to a variety of aircraft.

  18. Aircraft Laminar Flow Control

    NASA Technical Reports Server (NTRS)

    Joslin, Ronald D.

    1998-01-01

    Aircraft laminar flow control (LFC) from the 1930's through the 1990's is reviewed and the current status of the technology is assessed. Examples are provided to demonstrate the benefits of LFC for subsonic and supersonic aircraft. Early studies related to the laminar boundary-layer flow physics, manufacturing tolerances for laminar flow, and insect-contamination avoidance are discussed. LFC concept studies in wind-tunnel and flight experiments are the major focus of the paper. LFC design tools are briefly outlined for completeness.

  19. Alternative aircraft fuels

    NASA Technical Reports Server (NTRS)

    Longwell, J. P.; Grobman, J. S.

    1977-01-01

    The efficient utilization of fossil fuels by future jet aircraft may necessitate the broadening of current aviation turbine fuel specifications. The most significant changes in specifications would be an increased aromatics content and a higher final boiling point in order to minimize refinery energy consumption and costs. These changes would increase the freezing point and might lower the thermal stability of the fuel, and could cause increased pollutant emissions, increased combustor liner temperatures, and poorer ignition characteristics. The effects that broadened specification fuels may have on present-day jet aircraft and engine components and the technology required to use fuels with broadened specifications are discussed.

  20. Aircraft engine pollution reduction

    NASA Technical Reports Server (NTRS)

    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.

  1. Aircraft engines. II

    SciTech Connect

    Smith, M.G. Jr.

    1988-01-01

    An account is given of the design features and prospective performance gains of ultrahigh bypass subsonic propulsion configurations and various candidate supersonic commercial aircraft powerplants. The supersonic types, whose enhanced thermodynamic cycle efficiency is considered critical to the economic viability of a second-generation SST, are the variable-cycle engine, the variable stream control engine, the turbine-bypass engine, and the supersonic-throughflow fan. Also noted is the turboramjet concept, which will be applicable to hypersonic aircraft whose airframe structure materials can withstand the severe aerothermodynamic conditions of this flight regime.

  2. After the strike: using facilitation in a residency training program.

    PubMed

    Andres, D; Hamoline, D; Sanders, M; Anderson, J

    1998-03-10

    Methods of alternative dispute resolution, including facilitation, can be used to identify and resolve areas of conflict. Facilitation was used by the University of Saskatchewan's Department of Family Medicine (Saskatoon division) after the strike by residents in July and August 1995 so as to allow optimal use of the remaining educational time. Through facilitation, experiences of the strike and areas of potential conflict were explored. Participants had a broad range of responses to the strike. Specific coping strategies were developed to deal with identified concerns. Although outcomes were not measured formally, levels of trust improved and collegial relationships were restored. Because so many changes occur in health care and medical education, conflict inevitably arises. Facilitation offers one way of dealing with change constructively, thereby making possible the optimal use of educational time. PMID:9526479

  3. Structure as a causal factor in nurses' strikes.

    PubMed

    Hibberd, J M

    1988-01-01

    Nurses employed in Alberta's hospitals have earned a reputation of militancy as a result of four province-wide strikes in the 11-year period 1977-1988. Based on a case study of the first three strikes, the principal causes of the labour disputes are discussed: namely, union ideology, economic factors and inherent constraints in the structure of bargaining in the public sector. Interorganizational relationships of the three main players, the United Nurses of Alberta, the Alberta Hospital Association and the provincial government have been contributing factors in all three strikes. Although issues in the disputes were primarily economic, demands associated with the needs of working women, and demands that threatened the traditional prerogatives of management were at the heart of every impasse. PMID:10290776

  4. Comparison of Blade-Strike Modeling Results with Empirical Data

    SciTech Connect

    Carlson, Thomas J.; Ploskey, Gene R.

    2004-05-06

    This study is the initial stage of further investigation into the dynamics of injury to fish during passage through a turbine runner. As part of the study, Pacific Northwest National Laboratory (PNNL) estimated the probability of blade strike, and associated injury, as a function of fish length and turbine operating geometry at two adjacent turbines in Powerhouse 1 of Bonneville Dam. Units 5 and 6 had identical intakes, stay vanes, wicket gates, and draft tubes, but Unit 6 had a new runner and curved discharge ring to minimize gaps between the runner hub and blades and between the blade tips and discharge ring. We used a mathematical model to predict blade strike associated with two Kaplan turbines and compared results with empirical data from biological tests conducted in 1999 and 2000. Blade-strike models take into consideration the geometry of the turbine blades and discharges as well as fish length, orientation, and distribution along the runner.

  5. Comparison of blade-strike modeling results with empirical data

    SciTech Connect

    Ploskey, Gene R.; Carlson, Thomas J.

    2004-03-01

    This study is the initial stage of further investigation into the dynamics of injury to fish during passage through a turbine runner. As part of the study, Pacific Northwest National Laboratory (PNNL) estimated the probability of blade strike, and associated injury, as a function of fish length and turbine operating geometry at two adjacent turbines in Powerhouse 1 of Bonneville Dam. Units 5 and 6 had identical intakes, stay vanes, wicket gates, and draft tubes, but Unit 6 had a new runner and curved discharge ring to minimize gaps between the runner hub and blades and between the blade tips and discharge ring. We used a mathematical model to predict blade strike associated with two Kaplan turbines and compared results with empirical data from biological tests conducted in 1999 and 2000. Blade-strike models take into consideration the geometry of the turbine blades and discharges as well as fish length, orientation, and distribution along the runner. The first phase of this study included a sensitivity analysis to consider the effects of difference in geometry and operations between families of turbines on the strike probability response surface. The analysis revealed that the orientation of fish relative to the leading edge of a runner blade and the location that fish pass along the blade between the hub and blade tip are critical uncertainties in blade-strike models. Over a range of discharges, the average prediction of injury from blade strike was two to five times higher than average empirical estimates of visible injury from shear and mechanical devices. Empirical estimates of mortality may be better metrics for comparison to predicted injury rates than other injury measures for fish passing at mid-blade and blade-tip locations.

  6. Dynamic Ridges and Valleys in a Strike-Slip Environment

    NASA Astrophysics Data System (ADS)

    Duvall, Alison R.; Tucker, Gregory E.

    2015-10-01

    Strike-slip faults have long been known for characteristic near-fault landforms such as offset rivers and strike-parallel valleys. In this study, we use a landscape evolution model to investigate the longer-term, catchment-wide landscape response to horizontal fault motion. Our results show that strike-slip faulting induces a persistent state of disequilibrium in the modeled landscapes brought about by river lengthening along the fault alternating with abrupt shortening due to stream capture. The models also predict that, in some cases, ridges oriented perpendicular to the fault migrate laterally in conjunction with fault motion. We find that ridge migration happens when slip rate is slow enough and/or soil creep and river incision are efficient enough that the landscape can respond to the disequilibrium brought about by strike-slip motion. Regional rock uplift relative to baselevel also plays a role, as topographic relief is required for ridge migration. In models with faster horizontal slip rates, stronger rocks, or less efficient hillslope transport, ridge mobility is limited or arrested despite the continuance of river lengthening and capture. In these cases, prominent steep, fault-facing facets form along well-developed fault valleys. Comparison of landscapes adjacent to fast-slipping (>30 mm/yr) and slower-slipping (≤1 mm/yr or less) strike-slip faults in California, USA, reveals features that are consistent with model predictions. Our results highlight a potential suite of geomorphic signatures that can be used as indicators of horizontal crustal motion and geomorphic processes in strike-slip settings even after river capture has diminished or erased apparent offset along the fault.

  7. Optical communications for transport aircraft

    NASA Technical Reports Server (NTRS)

    Stengel, Robert

    1994-01-01

    Optical communications for transport aircraft are discussed. The problem involves: increasing demand for radio-frequency bands from an enlarging pool of users (aircraft, ground and sea vehicles, fleet operators, traffic control centers, and commercial radio and television); desirability of providing high-bandwidth dedicated communications to and from every aircraft in the National Airspace System; need to support communications, navigation, and surveillance for a growing number of aircraft; and improved meteorological observations by use of probe aircraft. The solution involves: optical signal transmission support very high data rates; optical transmission of signals between aircraft, orbiting satellites, and ground stations, where unobstructed line-of-sight is available; conventional radio transmissions of signals between aircraft and ground stations, where optical line-of-sight is unavailable; and radio priority given to aircraft in weather.

  8. Fish Passage though Hydropower Turbines: Simulating Blade Strike using the Discrete Element Method

    SciTech Connect

    Richmond, Marshall C.; Romero Gomez, Pedro DJ

    2014-12-08

    mong the hazardous hydraulic conditions affecting anadromous and resident fish during their passage though turbine flows, two are believed to cause considerable injury and mortality: collision on moving blades and decompression. Several methods are currently available to evaluate these stressors in installed turbines, i.e. using live fish or autonomous sensor devices, and in reduced-scale physical models, i.e. registering collisions from plastic beads. However, a priori estimates with computational modeling approaches applied early in the process of turbine design can facilitate the development of fish-friendly turbines. In the present study, we evaluated the frequency of blade strike and nadir pressure environment by modeling potential fish trajectories with the Discrete Element Method (DEM) applied to fish-like composite particles. In the DEM approach, particles are subjected to realistic hydraulic conditions simulated with computational fluid dynamics (CFD), and particle-structure interactions—representing fish collisions with turbine blades—are explicitly recorded and accounted for in the calculation of particle trajectories. We conducted transient CFD simulations by setting the runner in motion and allowing for better turbulence resolution, a modeling improvement over the conventional practice of simulating the system in steady state which was also done here. While both schemes yielded comparable bulk hydraulic performance, transient conditions exhibited a visual improvement in describing flow variability. We released streamtraces (steady flow solution) and DEM particles (transient solution) at the same location from where sensor fish (SF) have been released in field studies of the modeled turbine unit. The streamtrace-based results showed a better agreement with SF data than the DEM-based nadir pressures did because the former accounted for the turbulent dispersion at the intake but the latter did not. However, the DEM-based strike frequency is more

  9. [Force-feeding of hunger-striking prisoners].

    PubMed

    Glick, Shimon

    2014-09-01

    In contrast to the position of the World Medical Association and the Ethics Council of the Israel Medical Association, the author argues for forced-feeding of hunger-striking prisoners when their condition reaches a stage of danger of death or permanent injury. This position is based on the priority of human life over autonomy, and of a communitarian ethic. This position is supported by a District Court decision ordering the feeding of a hunger-striking prisoner, by a Supreme Court decision imposing surgery on a non-consenting prisoner, and in line with Israel's Patient's Right Law. PMID:25417495

  10. Preparing for radiological assessments in the event of a tornado strike at Argonne National Lab. -East

    SciTech Connect

    Goodkind, M.E.; Klimczak, C.A.; Munyon, W.J. )

    1993-01-01

    Argonne National Laboratory-East (ANL) is a Department of Energy (DOE)-owned, contractor-operated national laboratory located 22 miles southwest of downtown Chicago on a wooded, 1700-acre site. The principal nuclear facilities at ANL include a large fast neutron source (Intense Pulse Neutron Source) in which high-energy protons strike a uranium target to produce neutrons for research studies; [sup 60]Co irradiation sources; chemical and metallurgical plutonium laboratories, some of which are currently being decommissioned; several large hot cell facilities designed for work with multicurie quantities of actinide elements and irradiated reactor fuel materials; a few small research reactors currently in different phases of being decommissioned; and a variety of research laboratories handling many different sources in various chemical and physical forms. The hazards analysis for the ANL site shows that tornado strikes are a serious threat. The site has been struck twice in the past 20 yr, receiving only minor building damage and no release of radioactivity to the environment. Although radioactive materials in general are handled in areas that provide good tornado protection, ANL is prepared to address the problems that would occur should there be a loss of control of radioactive materials due to severe building damage.

  11. Light aircraft sound transmission study

    NASA Technical Reports Server (NTRS)

    Atwal, M.; David, J.; Heitman, K.; Crocker, M. J.

    1983-01-01

    The revived interest in the design of propeller driven aircraft is based on increasing fuel prices as well as on the need for bigger short haul and commuter aircraft. A major problem encountered with propeller driven aircraft is propeller and exhaust noise that is transmitted through the fuselage sidewall structure. Part of the work which was conducted during the period April 1 to August 31, 1983, on the studies of sound transmission through light aircraft walls is presented.

  12. Aircraft community noise impact studies

    NASA Technical Reports Server (NTRS)

    1977-01-01

    The objectives of the study are to: (1) conduct a program to determine the community noise impact of advanced technology engines when installed in a supersonic aircraft, (2) determine the potential reduction of community noise by flight operational techniques for the study aircraft, (3) estimate the community noise impact of the study aircraft powered by suppressed turbojet engines and by advanced duct heating turbofan engines, and (4) compare the impact of the two supersonic designs with that of conventional commercial DC-8 aircraft.

  13. The variable density aircraft concept

    NASA Technical Reports Server (NTRS)

    Davenport, A. C.

    1975-01-01

    In the variable density aircraft concept the aircraft's density is varied by varying its volume. This is accomplished by combining a variable volume hull, which is called the dynapod, with intrinsic means for the controlled variation of a mass of working fluid or substance within the aircraft. The dynapod is a hinged structure and follows the volumetric variations of the working fluid. The result is a variable density hull, which with the attachment of power plants, etc., becomes a variable density aircraft.

  14. Bibliography for aircraft parameter estimation

    NASA Technical Reports Server (NTRS)

    Iliff, Kenneth W.; Maine, Richard E.

    1986-01-01

    An extensive bibliography in the field of aircraft parameter estimation has been compiled. This list contains definitive works related to most aircraft parameter estimation approaches. Theoretical studies as well as practical applications are included. Many of these publications are pertinent to subjects peripherally related to parameter estimation, such as aircraft maneuver design or instrumentation considerations.

  15. A review of in-flight detection and identification of aircraft icing and reconfigurable control

    NASA Astrophysics Data System (ADS)

    Caliskan, Fikret; Hajiyev, Chingiz

    2013-07-01

    The recent improvements and research on aviation have focused on the subject of aircraft safe flight even in the severe weather conditions. As one type of such weather conditions, aircraft icing considerably has negative effects on the aircraft flight performance. The risks of the iced aerodynamic surfaces of the flying aircraft have been known since the beginning of the first flights. Until recent years, as a solution for this event, the icing conditions ahead flight route are estimated from radars or other environmental sensors, hence flight paths are changed, or, if it exists, anti-icing/de-icing systems are used. This work aims at the detection and identification of airframe icing based on statistical properties of aircraft dynamics and reconfigurable control protecting aircraft from hazardous icing conditions. In this review paper, aircraft icing identification based on neural network (NN), batch least-squares algorithm, Kalman filtering (KF), combined NN/KF, and H∞ parameter identification techniques are investigated, and compared with each other. Following icing identification, reconfigurable control is applied for protecting the aircraft from hazardous icing conditions.

  16. Aircraft noise prediction

    NASA Astrophysics Data System (ADS)

    Filippone, Antonio

    2014-07-01

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

  17. Aircraft Wake RCS Measurement

    NASA Technical Reports Server (NTRS)

    Gilson, William H.

    1994-01-01

    A series of multi-frequency radar measurements of aircraft wakes at altitudes of 5,000 to 25,00 ft. were performed at Kwajalein, R.M.I., in May and June of 1990. Two aircraft were tested, a Learjet 35 and a Lockheed C-5A. The cross-section of the wake of the Learjet was too small for detection at Kwajalein. The wake of the C-5A, although also very small, was detected and measured at VHF, UHF, L-, S-, and C-bands, at distances behind the aircraft ranging from about one hundred meters to tens of kilometers. The data suggest that the mechanism by which aircraft wakes have detectable radar signatures is, contrary to previous expectations, unrelated to engine exhaust but instead due to turbulent mixing by the wake vortices of pre-existing index of refraction gradients in the ambient atmosphere. These measurements were of necessity performed with extremely powerful and sensitive instrumentation radars, and the wake cross-section is too small for most practical applications.

  18. Counterrotating aircraft propulsor blades

    NASA Technical Reports Server (NTRS)

    Nelson, Joey L. (Inventor); Elston, III, Sidney B. (Inventor); Tseng, Wu-Yang (Inventor); Hemsworth, Martin C. (Inventor)

    1993-01-01

    A propulsor blade for an aircraft engine includes an airfoil section formed in the shape of a scimitar. A metallic blade spar is interposed between opposed surfaces of the blade and is bonded to the surfaces to establish structural integrity of the blade. The metallic blade spar includes a root end allowing attachment of the blade to the engine.

  19. Counterrotating aircraft propulsor blades

    NASA Technical Reports Server (NTRS)

    Nelson, Joey L. (Inventor); Elston, III, Sidney B. (Inventor); Tseng, Wu-Yang (Inventor); Hemsworth, Martin C. (Inventor)

    1988-01-01

    A propulsor blade for an aircraft engine includes an airfoil section formed in the shape of a scimitar. A metallic blade spar is interposed between opposed surfaces of the blade and is bonded to the surfaces to establish structural integrity of the blade. The metallic blade spar includes a root end allowing attachment of the blade to the engine.

  20. Robots for Aircraft Maintenance

    NASA Technical Reports Server (NTRS)

    1993-01-01

    Marshall Space Flight Center charged USBI (now Pratt & Whitney) with the task of developing an advanced stripping system based on hydroblasting to strip paint and thermal protection material from Space Shuttle solid rocket boosters. A robot, mounted on a transportable platform, controls the waterjet angle, water pressure and flow rate. This technology, now known as ARMS, has found commercial applications in the removal of coatings from jet engine components. The system is significantly faster than manual procedures and uses only minimal labor. Because the amount of "substrate" lost is minimal, the life of the component is extended. The need for toxic chemicals is reduced, as is waste disposal and human protection equipment. Users of the ARMS work cell include Delta Air Lines and the Air Force, which later contracted with USBI for development of a Large Aircraft Paint Stripping system (LARPS). LARPS' advantages are similar to ARMS, and it has enormous potential in military and civil aircraft maintenance. The technology may also be adapted to aircraft painting, aircraft inspection techniques and paint stripping of large objects like ships and railcars.

  1. Aircraft adaptive learning control

    NASA Technical Reports Server (NTRS)

    Lee, P. S. T.; Vanlandingham, H. F.

    1979-01-01

    The optimal control theory of stochastic linear systems is discussed in terms of the advantages of distributed-control systems, and the control of randomly-sampled systems. An optimal solution to longitudinal control is derived and applied to the F-8 DFBW aircraft. A randomly-sampled linear process model with additive process and noise is developed.

  2. Ozone and aircraft operations

    NASA Technical Reports Server (NTRS)

    Perkins, P. J.

    1981-01-01

    The cabin ozone problem is discussed. Cabin ozone in terms of health effects, the characteristics of ozone encounters by aircraft, a brief history of studies to define the problem, corrective actions taken, and possible future courses of action are examined. It is suggested that such actions include avoiding high ozone concentrations by applying ozone forecasting in flight planning procedures.

  3. Occupational Hazards of Farming

    PubMed Central

    White, Gill; Cessna, Allan

    1989-01-01

    A number of occupational hazards exist for the farmer and farm worker. They include the hazards of farm machinery, biologic and chemical hazards, and social and environmental stresses. Recognizing of these hazards will help the family physician care for farmers and their families. PMID:21248929

  4. Kinematically Coupled Strike-Slip and Normal Faults in the Lake Mead Strike-Slip Fault System, Southeast Nevada

    NASA Astrophysics Data System (ADS)

    Kattenhorn, S. A.; Marshall, S. T.; Cooke, M. L.

    2008-12-01

    The Lake Mead fault system consists of a ~95 km long, northeast-trending zone of strike-slip faults of Miocene age that accommodate a total left-lateral offset of 20-65 km. We use a combination of detailed field mapping and numerical modeling to show that a previously unnamed left-lateral strike-slip segment of the Lake Mead fault system and a dense cluster of dominantly west-dipping normal faults acted in concert to accommodate regional left-lateral offset. We suggest that the strike-slip fault that we refer to as the Pinto Ridge fault: (1) was kinematically related to other faults of the Lake Mead fault system; (2) was responsible for the creation of the normal fault cluster at Pinto Ridge; and (3) utilized these normal faults as linking structures between separate strike-slip fault segments to create a longer, through-going fault. Results from numerical models demonstrate that the observed location and curving strike patterns of the normal fault cluster is consistent with the faults having formed as secondary structures as the result of the perturbed stress field around the slipping Pinto Ridge fault. Comparison of mechanical efficiency of various normal fault geometries within extending terranes suggests that the observed west dip of normal faults reflects a west- dipping anisotropy at depth, such as a detachment. The apparent terminations of numerous strike-slip faults of the Lake Mead fault system into west-dipping normal faults suggest that a west-dipping detachment may be regionally coherent.

  5. Impact damage in aircraft composite sandwich panels

    NASA Astrophysics Data System (ADS)

    Mordasky, Matthew D.

    An experimental study was conducted to develop an improved understanding of the damage caused by runway debris and environmental threats on aircraft structures. The velocities of impacts for stationary aircraft and aircraft under landing and takeoff speeds was investigated. The impact damage by concrete, asphalt, aluminum, hail and rubber sphere projectiles was explored in detail. Additionally, a kinetic energy and momentum experimental study was performed to look at the nature of the impacts in more detail. A method for recording the contact force history of the impact by an instrumented projectile was developed and tested. The sandwich composite investigated was an IM7-8552 unidirectional prepreg adhered to a NOMEXRTM core with an FM300K film adhesive. Impact experiments were conducted with a gas gun built in-house specifically for delivering projectiles to a sandwich composite target in this specic velocity regime (10--140 m/s). The effect on the impact damage by the projectile was investigated by ultrasonic C-scan, high speed camera and scanning electron and optical microscopy. Ultrasonic C-scans revealed the full extent of damage caused by each projectile, while the high speed camera enabled precise projectile velocity measurements that were used for striking velocity, kinetic energy and momentum analyses. Scanning electron and optical images revealed specific features of the panel failure and manufacturing artifacts within the lamina and honeycomb core. The damage of the panels by different projectiles was found to have a similar damage area for equivalent energy levels, except for rubber which had a damage area that increased greatly with striking velocity. Further investigation was taken by kinetic energy and momentum based comparisons of 19 mm diameter stainless steel sphere projectiles in order to examine the dominating damage mechanisms. The sandwich targets were struck by acrylic, aluminum, alumina, stainless steel and tungsten carbide spheres of the

  6. Torts Liability for Strike Action and Third Party Rights.

    ERIC Educational Resources Information Center

    Raday, Frances

    1979-01-01

    Studies the nature of the torts liability incurred in strikes and the extent of existing immunities bestowed on strikers and their organizers, and explores the principles that should govern liability and immunity. Available from Israel Law Review Association, c/o Faculty of Law, Hebrew University of Jerusalem, Mount Scopus, P.O.B. 24100, Jerusalem…

  7. Monte Carlo Simulation to Estimate Likelihood of Direct Lightning Strikes

    NASA Technical Reports Server (NTRS)

    Mata, Carlos; Medelius, Pedro

    2008-01-01

    A software tool has been designed to quantify the lightning exposure at launch sites of the stack at the pads under different configurations. In order to predict lightning strikes to generic structures, this model uses leaders whose origins (in the x-y plane) are obtained from a 2D random, normal distribution.

  8. Second, Unrelated Cancers Strike 1 in 12 Cancer Patients

    MedlinePlus

    ... medlineplus.gov/news/fullstory_159759.html Second, Unrelated Cancers Strike 1 in 12 Cancer Patients Unfortunately, they're often deadly To use ... in 12 -- already diagnosed with one form of cancer end up developing a second type of unrelated ...

  9. Lightning-Strike Disaster: Effects on Children's Fears and Worries.

    ERIC Educational Resources Information Center

    Dollinger, Stephen J.; And Others

    1984-01-01

    Compares fears of lightning-strike victims (N=29) with matched control children (N=58), using fear reports from children and their mothers. Differences between samples were most pronounced for child-reported fears. Correspondence between mothers' and children's reports of intense storm-related fears was markedly larger in the lightning sample than…

  10. Second, Unrelated Cancers Strike 1 in 12 Cancer Patients

    MedlinePlus

    ... gov/medlineplus/news/fullstory_159759.html Second, Unrelated Cancers Strike 1 in 12 Cancer Patients Unfortunately, they're often deadly To use ... in 12 -- already diagnosed with one form of cancer end up developing a second type of unrelated ...

  11. Suicidal protests: self-immolation, hunger strikes, or suicide bombing.

    PubMed

    Lester, David

    2014-08-01

    Following Lankford's persuasive argument that suicide bombers are indeed suicidal, the next question to ask is why individuals choose one form of suicidal protest over others. Why choose suicide bombing rather than a hunger strike or self-immolation? Some suggestions are provided. PMID:25162850

  12. Faculty Strikes in Higher Education: 1966-1994.

    ERIC Educational Resources Information Center

    Annunziato, Frank R.

    1994-01-01

    Over the 29-year period from 1966 to 1994, the number of faculty strikes recorded by the National Center for the Study of Collective Bargaining in Higher Education and the Professions totaled 163. They transpired in 96 two-year and 67 four-year institutions. The vast majority involved faculty members employed at public sector colleges and…

  13. Formation and Suppression of Strike-Slip Fault Systems

    NASA Astrophysics Data System (ADS)

    Curren, Ivy S.; Bird, Peter

    2014-11-01

    Strike-slip faults are a defining feature of plate tectonics, yet many aspects of their development and evolution remain unresolved. For intact materials and/or regions, a standard sequence of shear development is predicted from physical models and field studies, commencing with the formation of Riedel shears and culminating with the development of a throughgoing fault. However, for materials and/or regions that contain crustal heterogeneities (normal and/or thrust faults, joints, etc.) that predate shear deformation, kinematic evolution of strike-slip faulting is poorly constrained. We present a new plane-stress finite-strain physical analog model developed to investigate primary deformation zone evolution in simple shear, pure strike-slip fault systems in which faults or joints are present before shear initiation. Experimental results suggest that preexisting mechanical discontinuities (faults and/or joints) have a marked effect on the geometry of such systems, causing deflection, lateral distribution, and suppression of shears. A lower limit is placed on shear offset necessary to produce a throughgoing fault in systems containing preexisting structures. Fault zone development observed in these experiments provides new insight for kinematic interpretation of structural data from strike-slip fault zones on Earth, Venus, and other terrestrial bodies.

  14. When the Corporate Storm Strikes the Academy: Faculty Response Required

    ERIC Educational Resources Information Center

    DeBoy, James L.

    2015-01-01

    When the corporate storm strikes the academy, faculty must be willing and able to repel administrative assaults upon academic freedom, shared governance, and tenure. This paper will describe the on-going clash between administrators who embrace the corporate mindset and faculty who cherish traditions of shared governance and collegial…

  15. What To Do When Contagious Disease Strikes Your School.

    ERIC Educational Resources Information Center

    American Bar Association, Chicago, IL.

    This publication presents 10 documents collected to accompany a seminar entitled "What To Do When Contagious Disease Strikes Your School," presented at the 31st annual convention of the National Organization on Legal Problems of Education in 1985. The materials include (1) an agenda of the seminar listing the speakers, their topics, and the time…

  16. Strike Four: An Educational Paradigm Servicing Troublesome Behaviour Students.

    ERIC Educational Resources Information Center

    Netolicky, Cecilia

    For chronically troublesome students educational strategies of exclusion currently lead to revolving door syndrome, resulting in ever-increasing learning deficits, and further inappropriate behaviours. Strike Four is an educational paradigm servicing "category three alienated students" (exhibiting significant social and/or emotional difficulties…

  17. Topic 101: Eleven Campuses, One University, Many Strikes

    ERIC Educational Resources Information Center

    Navarro-Rivera, Pablo

    2010-01-01

    Students from the University of Puerto Rico (UPR) went on strike in April, and, soon after, 10 of the 11 campuses of a public system with more than 60,000 students were closed. "Once recintos, una universidad" (eleven campuses, one university) was the maxim students used to emphasize the concept of the UPR as a system unified by similar goals,…

  18. Determinants of Teacher Militancy: Factors Affecting the Decision to Strike.

    ERIC Educational Resources Information Center

    Tomkiewicz, Joseph

    1979-01-01

    Statistical analysis of factors offered as explanations for teacher militancy demonstrates that they possess little value in differentiating striking from nonstriking school districts. Boards cannot depend on objective measures alone in preparing for negotiations and might better aim their efforts in other directions. (Author/IRT)

  19. Using Primary Sources To Teach the Rail Strike of 1877.

    ERIC Educational Resources Information Center

    Lesh, Bruce

    1999-01-01

    Describes a lesson plan that utilizes two primary sources, a handbill announcing the reduction in Baltimore and Ohio rail workers' wages and a list of damages to Baltimore and Ohio Railroad property, in order to determine the causes and effects of the Rail Strike of 1877. Provides the two sources and other handouts. (CMK)

  20. Physicians' strike and general mortality: Croatia's experience of 2003.

    PubMed

    Erceg, Marijan; Kujundzić-Tiljak, Mirjana; Babić-Erceg, Andrea; Coric, Tanja; Lang, Slobodan

    2007-09-01

    The aim of the study was to establish whether the physicians' strike, which took place in Croatia in 2003, had an impact on the mortality of the population. Mortality data from the National Bureau of Statistics relating to the strike period (15 January - 14 February 2003) were selected and compared with the previous and subsequent periods of the same duration in 2001, 2002 and 2004. Of the 52,575 deaths in 2003, Croatia recorded 4,682 (8.9%, 95% Confidence interval 8.4-9.4) in the strike period from the 15th of January to the 14th of February 2003 or 1.1 deaths per 1000. No deviations of the 15th of January to the 14th of February period's share of the death total in relation to other observation periods were noted. It is impossible to associate the strike based on the figures shown in this paper with either an increase or decrease in population mortality. PMID:18041403

  1. Introduction: Mapping Teachers' Strikes--A "Professionalist" Approach

    ERIC Educational Resources Information Center

    Robert, Andre D.; Tyssens, Jeffrey

    2008-01-01

    This article aims to interpret teacher strikes through a multi-level analysis and the identification of a number of relevant factors relative to the professional project (in a neo-Weberian sense) of primary and secondary school teachers. In the first place the authors' interpretation is based on references to contextual and structural elements,…

  2. In situ turbulence measurements from commercial aircraft

    NASA Astrophysics Data System (ADS)

    Sharman, Robert; Pearson, Julia; Meymaris, Greg; Cornman, Larry; Blackburn, Gary; Farrar, Tammy

    2013-04-01

    The statistical properties of turbulence at upper-levels in the atmosphere (upper troposphere and lower stratosphere or UTLS) are still not very well-known, partly because of the lack of adequate routine observations. This is in spite of the use that such observations would have in better quantifying dissipation rates in the atmosphere due to turbulence, but also for the practical value this information would have in alerting aircraft of potentially hazardous conditions, either in real-time or for climatological route planning. To address this, in the U.S. a program has been underway over the last few years to outfit commercial aircraft with a software package that automatically estimates and reports atmospheric turbulence intensity levels (as ɛ^1/3 where ɛ is the eddy dissipation rate) during each minute of flight. The reporting frequency is variable depending on the airline, but some reports are routinely made once per minute while others report only when the turbulence level exceeds some threshold or "trigger". The amount of turbulence data gathered is unprecedented - as of Jan 2013 there are ~ 200 aircraft outfitted with this system, contributing to well over 140 million archived records of ɛ^1/3 mostly at cruise levels of commercial aircraft, i.e., in the UTLS. In this talk the results of some statistical analyses of these ɛ^1/3 values will be presented, including vertical distributions, horizontal distributions, turbulence patch lengths and depths, and probability distribution functions (PDFs). These analyses are restricted to the U.S. for now, but as this program is expanded to international carriers, such data will begin to become available over other areas of the globe, including the North Atlantic and Europe.

  3. Fires in P-3 Aircraft Oxygen Systems

    NASA Technical Reports Server (NTRS)

    Stoltzfus, Joel

    2006-01-01

    Fires in three P3 aircraft oxygen systems have occurred: one in the Royal Australian Air Force (RAAF) in 1984 and two in the U.S. Navy in 1998 and 2003. All three fires started in the aluminum manifold and check valve (MCV) assembly and produced similar damages to the aircraft in which they occurred. This paper discusses a failure analysis conducted by the NASA Johnson Space Center White Sands Test Facility (WSTF) Oxygen Hazards and Testing Team on the 2003 U.S. Navy VP62 fire. It was surmised that the fire started due to heat generated by an oxygen leak past a silicone check valve seal or possibly because of particle impact near the seat of one of the MCV assembly check valves. An additional analysis of fires in several check valve poppet seals from other aircraft is discussed. These burned poppet seals came from P3 oxygen systems that had been serviced at the Naval Air Station (NAS) in Jacksonville following standard fill procedures. It was concluded that these seal fires occurred due to the heat from compression heating, particle impact, or the heat generated by an oxygen leak past the silicone check valve seal. The fact that catastrophic fires did not occur in the case of each check valve seal fire was attributed to the protective nature of the aluminum oxide layer on the check valve poppets. To prevent future fires of this nature, the U.S. and Canadian fleets of P3 aircraft have been retrofitted with MCV assemblies with an upgraded design and more burn-resistant materials.

  4. Aircraft Icing Weather Data Reporting and Dissemination System

    NASA Technical Reports Server (NTRS)

    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.

  5. Advanced ATC - An aircraft perspective

    NASA Technical Reports Server (NTRS)

    Credeur, L.; Williams, D. H.; Howell, W. E.; Spitzer, C. R.

    1986-01-01

    The principal operational improvements desired by commercial aircraft operators in the United States are efficient aircraft operations and delay reductions at the major terminals. This paper describes efforts underway within the Advanced Transport Operating Systems Program at the Langley Research Center to provide a technology basis for reducing delay while improving aircraft efficiency. The principal thrust is the development of time-based traffic control concepts which could be used within the framework of the upgraded National Airspace System and which would allow conventionally equipped aircraft to operate in a manner compatible with advanced aircraft.

  6. Turboprop cargo aircraft systems study

    NASA Technical Reports Server (NTRS)

    Muehlbauer, J. C.; Hewell, J. G., Jr.; Lindenbaum, S. P.; Randall, C. C.; Searle, N.; Stone, R. G., Jr.

    1981-01-01

    The effects of using advanced turboprop propulsion systems to reduce the fuel consumption and direct operating costs of cargo aircraft were studied, and the impact of these systems on aircraft noise and noise prints around a terminal area was determined. Parametric variations of aircraft and propeller characteristics were investigated to determine their effects on noiseprint areas, fuel consumption, and direct operating costs. From these results, three aircraft designs were selected and subjected to design refinements and sensitivity analyses. Three competitive turbofan aircraft were also defined from parametric studies to provide a basis for comparing the two types of propulsion.

  7. Advanced ATC: An aircraft perspective

    NASA Technical Reports Server (NTRS)

    Credeur, Leonard; Williams, David H.; Howell, William E.; Spitzer, Cary R.

    1986-01-01

    The principal operational improvements desired by commercial aircraft operators in the United States are efficient aircraft operations and delay reductions at the major terminals. Efforts underway within the Advanced Transport Operating Systems Program at the Langley Research Center to provide a technology basis for reducing delay while improving aircraft efficiency are discussed. The principal thrust is the development of time-based traffic control concepts which could be used within the framework of the upgraded National Airspace System and which would allow conventionally equipped aircraft to operate in a manner compatible with advanced aircraft.

  8. Abrupt along-strike change in tectonic style: San Andreas fault zone, San Francisco Peninsula

    USGS Publications Warehouse

    Zoback, M.L.; Jachens, R.C.; Olson, J.A.

    1999-01-01

    Andreas right stepover region and at least 15 km along-strike both to the SE and NW. The 1906 San Francisco earthquake may have nucleated within the San Andreas right stepover, which may help explain the bilateral nature of rupture of this event. Our analysis suggests two seismic hazards for the San Francisco Peninsula in addition to the hazard associated with a M = 7 to 8 strike-slip earthquake along the San Andreas fault: the potential for a M ??? 6 normal-faulting earthquake just 5-8 km west of San Francisco and a M = 6+ thrust faulting event in the southern peninsula.

  9. Recent physician strike in Israel: a health system under stress?

    PubMed Central

    2013-01-01

    In 2011, a series of physician strikes in Israel followed eight months of unsuccessful negotiations with the government (Ministry of Health and the Ministry of Finance). Strikes by physicians may be a warning that all is not well in a health system and protestors have claimed that they signify a system failure. In contrast, others argue that strikes have been a feature of the Israeli health system from its inception and should not be a cause for alarm. This paper analyses the Israeli health system from the perspective of the strikers' demands using the World Health Organisation’s six health system building blocks as a framework, including: service delivery; health workforce; information; medical products, vaccines and technologies; leadership and governance; and financing. While we recognise that the immediate causes of the 2011 strikes were concerns about salaries and working conditions, we argue that a complex set of interacting factors underlie the strikers' demands, resonating with issues relating to five of the WHO building blocks. We argue that of the five, three are most significant and limit progress with all the others: a disgruntled health workforce, many of whom believe that striking is the only way to be heard; a lack of leadership by the government in understanding and responding to physicians' concerns; and a purported information insufficiency, manifest as a lack of critique and analysis that may have prevented those at the top from making a reliable diagnosis of the system’s problems. This paper argues that there are cracks within the Israeli health system but that these are not irresolvable. The Israeli health system is a relatively new and popular health system, but there are no grounds for complacency. PMID:23947638

  10. Aircraft wake-vortex minimization by use of flaps

    NASA Technical Reports Server (NTRS)

    Corsiglia, V. R.; Dunham, R. E., Jr.

    1977-01-01

    A survey was made of research on the alleviation of the trailing vortex hazard by altering span loading with flaps on the generator airplane. Flap configurations of the generator that shed multiple vortices were found to have wakes that dispersed by vortex merging and sinusoidal instability. Reductions of approximately 50 percent in both the wake rolling moment imposed on a following aircraft and the aircraft separation requirement were achieved in the ground based and flight test experiments by deflecting the trailing edge flaps more inboard than outboard. Significantly, this configuration did not increase the drag or vibration on the generating aircraft compared to the conventional landing configuration. Ground based results of rolling moment measurement and flow visualization are shown, using a water tow facility, an air tow facility, and a wind tunnel. Flight test results are also shown, using a full scale B-747 airplane. General agreement was found among the results of the various ground based facilities and the flight tests.

  11. An evaluation of the relative fire hazards of jet A and jet B for commercial flight

    NASA Technical Reports Server (NTRS)

    Hibbard, R. R.; Hacker, P. T.

    1973-01-01

    The relative fire hazards of Jet A and Jet B aircraft fuels are evaluated. The evaluation is based on a consideration of the presence of and/or the generation of flammable mixtures in fuel systems, the ignition characteristics, and the flame propagation rates for the two fuel types. Three distinct aircraft operating regimes where fuel type may be a factor in fire hazards are considered. These are: (1) ground handling and refueling, (2) flight, and (3) crash. The evaluation indicates that the overall fire hazards for Jet A are less than for Jet B fuel.

  12. Hazard function theory for nonstationary natural hazards

    NASA Astrophysics Data System (ADS)

    Read, L.; Vogel, R. M.

    2015-12-01

    Studies from the natural hazards literature indicate that many natural processes, including wind speeds, landslides, wildfires, precipitation, streamflow and earthquakes, show evidence of nonstationary behavior such as trends in magnitudes through time. Traditional probabilistic analysis of natural hazards based on partial duration series (PDS) generally assumes stationarity in the magnitudes and arrivals of events, i.e. that the probability of exceedance is constant through time. Given evidence of trends and the consequent expected growth in devastating impacts from natural hazards across the world, new methods are needed to characterize their probabilistic behavior. The field of hazard function analysis (HFA) is ideally suited to this problem because its primary goal is to describe changes in the exceedance probability of an event over time. HFA is widely used in medicine, manufacturing, actuarial statistics, reliability engineering, economics, and elsewhere. HFA provides a rich theory to relate the natural hazard event series (x) with its failure time series (t), enabling computation of corresponding average return periods and reliabilities associated with nonstationary event series. This work investigates the suitability of HFA to characterize nonstationary natural hazards whose PDS magnitudes are assumed to follow the widely applied Poisson-GP model. We derive a 2-parameter Generalized Pareto hazard model and demonstrate how metrics such as reliability and average return period are impacted by nonstationarity and discuss the implications for planning and design. Our theoretical analysis linking hazard event series x, with corresponding failure time series t, should have application to a wide class of natural hazards.

  13. Fish passage through hydropower turbines: Simulating blade strike using the discrete element method

    NASA Astrophysics Data System (ADS)

    Richmond, M. C.; Romero-Gomez, P.

    2014-03-01

    Among the hazardous hydraulic conditions affecting anadromous and resident fish during their passage though hydro-turbines two common physical processes can lead to injury and mortality: collisions/blade-strike and rapid decompression. Several methods are currently available to evaluate these stressors in installed turbines, e.g. using live fish or autonomous sensor devices, and in reduced-scale physical models, e.g. registering collisions from plastic beads. However, a priori estimates with computational modeling approaches applied early in the process of turbine design can facilitate the development of fish-friendly turbines. In the present study, we evaluated the frequency of blade strike and rapid pressure change by modeling potential fish trajectories with the Discrete Element Method (DEM) applied to fish-like composite particles. In the DEM approach, particles are subjected to realistic hydraulic conditions simulated with computational fluid dynamics (CFD), and particle-structure interactions-representing fish collisions with turbine components such as blades-are explicitly recorded and accounted for in the calculation of particle trajectories. We conducted transient CFD simulations by setting the runner in motion and allowing for unsteady turbulence using detached eddy simulation (DES), as compared to the conventional practice of simulating the system in steady state (which was also done here for comparison). While both schemes yielded comparable bulk hydraulic performance values, transient conditions exhibited an improvement in describing flow temporal and spatial variability. We released streamtraces (in the steady flow solution) and DEM particles (transient solution) at the same locations where sensor fish (SF) were released in previous field studies of the advanced turbine unit. The streamtrace- based results showed a better agreement with SF data than the DEM-based nadir pressures did because the former accounted for the turbulent dispersion at the

  14. Analogue modelling of the effect of topographic steps in the development of strike-slip faults

    NASA Astrophysics Data System (ADS)

    Tomás, Ricardo; Duarte, João C.; Rosas, Filipe M.; Schellart, Wouter; Strak, Vincent

    2016-04-01

    Strike-slip faults often cut across regions of overthickened crust, such as oceanic plateaus or islands. These morphological steps likely cause a local variation in the stress field that controls the geometry of these systems. Such variation in the stress field will likely play a role in strain localization and associated seismicity. This is of particular importance since wrench systems can produce very high magnitude earthquakes. However, such systems have been generally overlooked and are still poorly understood. In this work we will present a set of analogue models that were designed with the objective of understanding how a step in the morphology affects the development of a strike-slip fault system. The models consist of a sand-cake with two areas with different thicknesses connected by a gentle ramp perpendicular to a dextral strike-slip basal fault. The sand-cake lies above two basal plates to which the dextral relative motion was imposed using a stepping-motor. Our results show that a Riedel fault system develops across the two flat areas. However, a very asymmetric fault pattern develops across the morphological step. A deltoid constrictional bulge develops in the thinner part of the model, which progressively acquires a sigmoidal shape with increasing offset. In the thicker part of the domain, the deformation is mostly accommodated by Riedel faults and the one closer to the step acquires a relatively lower angle. Associated to this Riedel fault a collapse area develops and amplifies with increasing offset. For high topographic steps, the propagation of the main fault across the step area only occurs in the final stages of the experiments, contrary to what happens when the step is small or inexistent. These results strongly suggest a major impact of the variation of topography on the development of strike-slip fault systems. The step in the morphology causes variations in the potential energy that changes the local stress field (mainly the vertical

  15. Lightning damage to a general aviation aircraft: Description and analysis

    NASA Technical Reports Server (NTRS)

    Hacker, P. T.

    1974-01-01

    The damage sustained by a Beechcraft King Air Model B90 aircraft by a single lightning discharge is presented and analyzed. The incident occurred during landing approach at Jackson, Michigan, on Feb. 19, 1971. In addition to the usual melted-metal damage at the lightning attachment points, there was severe implosion-type damage over a large area on the lower right side of the aircraft and impact- and crushing-type damage on the upper and lower surfaces on the left wingtip near the trailing edge. Analyses indicate that the implosion-type damage was probably caused by lightning-generated shock waves, that the impact-and crushing-type damage was caused by magnetic forces, and that the lightning discharge was a multiple strike with at least 11 strokes separated in time by about 4.5 milliseconds. The evidence indicates that the lightning discharge was rather different from the average in character severity.

  16. Patterns of variation in feeding strike kinematics of juvenile ghost praying mantis (Phyllocrania paradoxa): are components of the strike stereotypic?

    PubMed

    Oufiero, Christopher E; Nguyen, Tammy; Sragner, Annie; Ellis, Angelah

    2016-09-01

    Functional systems, such as feeding mechanics, often involve the evolution of several components of the musculoskeletal system that are moved in coordination to capture prey. Because these systems often involve the quick movement of several structures, some feeding systems have been hypothesized to be stereotypic. While the motor activity patterns are often stereotyped, the subsequent kinematics can be variable, many times in response to variation in prey stimulus (e.g. prey position). Patterns of feeding kinematics have been well studied among vertebrates, with less attention on invertebrate systems. The goal of this study was to examine the amount of stereotypy in the feeding strike kinematics of praying mantises. We filmed eight juvenile ghost praying mantises (Phyllocrania paradoxa) at 1000 Hz across several days within instar 7. We digitized several points that represent the movement of the coxa, trochanter-femur and tibia of the raptorial foreleg to obtain a set of kinematics including angles and angular velocities of the joint, as well as body lunge. Using the coefficient of variation, we found less stereotypy in the approach stage of the strike compared with the sweep. Using Bonferroni-corrected Pearson's correlations of kinematics with prey position, we found few traits related to prey position with the exception of some kinematics of the coxa joint and the amount of lunge used during the strike. Our results suggest that several components of the praying mantis strike are stereotypic, while others exhibit flexibility to ensure successful capture of the prey. PMID:27358472

  17. Implications of Incessant Strike Actions on the Implementation of Technical Education Programme in Nigeria

    ERIC Educational Resources Information Center

    Adavbiele, J. A.

    2015-01-01

    This paper was designed to x-ray the implications of incessant strike actions on the implementation of Technical education programme in Nigeria. The paper took an exploratory view on the concept of strike actions in Nigeria with particular references on notable strike actions that have occurred in Nigeria. The types of strike were explained and…

  18. Autonomous aircraft initiative study

    NASA Technical Reports Server (NTRS)

    Hewett, Marle D.

    1991-01-01

    The results of a consulting effort to aid NASA Ames-Dryden in defining a new initiative in aircraft automation are described. The initiative described is a multi-year, multi-center technology development and flight demonstration program. The initiative features the further development of technologies in aircraft automation already being pursued at multiple NASA centers and Department of Defense (DoD) research and Development (R and D) facilities. The proposed initiative involves the development of technologies in intelligent systems, guidance, control, software development, airborne computing, navigation, communications, sensors, unmanned vehicles, and air traffic control. It involves the integration and implementation of these technologies to the extent necessary to conduct selected and incremental flight demonstrations.

  19. Aircraft Design Software

    NASA Technical Reports Server (NTRS)

    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.

  20. Aircraft engine pollution reduction.

    NASA Technical Reports Server (NTRS)

    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.

  1. Aircraft turbofan noise

    NASA Technical Reports Server (NTRS)

    Groeneweg, J. F.; Rice, E. J.

    1983-01-01

    Turbofan noise generation and suppression in aircraft engines are reviewed. The chain of physical processes which connect unsteady flow interactions with fan blades to far field noise is addressed. Mechanism identification and description, duct propagation, radiation and acoustic suppression are discussed. The experimental technique of fan inflow static tests are discussed. Rotor blade surface pressure and wake velocity measurements aid in the determination of the types and strengths of the generation mechanisms. Approaches to predicting or measuring acoustic mode content, optimizing treatment impedance to maximize attenuation, translating impedance into porous wall structure and interpreting far field directivity patterns are illustrated by comparisons of analytical and experimental results. The interdependence of source and acoustic treatment design to minimize far field noise is emphasized. Area requiring further research are discussed and the relevance of aircraft turbofan results to quieting other turbomachinery installations is addressed.

  2. Air pollution from aircraft

    NASA Technical Reports Server (NTRS)

    Heywood, J. B.; Fay, J. A.; Chigier, N. A.

    1979-01-01

    Forty-one annotated abstracts of reports generated at MIT and the University of Sheffield are presented along with summaries of the technical projects undertaken. Work completed includes: (1) an analysis of the soot formation and oxidation rates in gas turbine combustors, (2) modelling the nitric oxide formation process in gas turbine combustors, (3) a study of the mechanisms causing high carbon monoxide emissions from gas turbines at low power, (4) an analysis of the dispersion of pollutants from aircraft both around large airports and from the wakes of subsonic and supersonic aircraft, (5) a study of the combustion and flow characteristics of the swirl can modular combustor and the development and verification of NO sub x and CO emissions models, (6) an analysis of the influence of fuel atomizer characteristics on the fuel-air mixing process in liquid fuel spray flames, and (7) the development of models which predict the stability limits of fully and partially premixed fuel-air mixtures.

  3. Project report: Aircraft

    SciTech Connect

    Wuebbles, D.J.; Baughcum, S.; Metwally, M.; Seals, R.

    1994-04-01

    Analyses of scenarios of past and possible future emissions are an important aspect of assessing the potential environmental effects from aircraft, including the proposed high speed civil transport (HSCT). The development of a detailed three-dimensional database that accurately represents the integration of all aircraft emissions along realistic flight paths for such scenarios requires complex computational modeling capabilities. Such a detailed data set is required for the scenarios evaluated in this interim assessment. Within the NASA High-Speed Research Program, the Emissions Scenarios Committee provides a forum for identifying the required scenarios and evaluating the resulting database being developed with the advanced emissions modeling capabilities at the Boeing Company and McDonnell Douglas Corporation.

  4. Energy efficient aircraft engines

    NASA Technical Reports Server (NTRS)

    Chamberlin, R.; Miller, B.

    1979-01-01

    The three engine programs that constitute the propulsion portion of NASA's Aircraft Energy Efficiency Program are described, their status indicated, and anticipated improvements in SFC discussed. The three engine programs are (1) Engine Component Improvement--directed at current engines, (2) Energy Efficiency Engine directed at new turbofan engines, and (3) Advanced Turboprops--directed at technology for advanced turboprop--powered aircraft with cruise speeds to Mach 0.8. Unique propulsion system interactive ties to the airframe resulting from engine design features to reduce fuel consumption are discussed. Emphasis is placed on the advanced turboprop since it offers the largest potential fuel savings of the three propulsion programs and also has the strongest interactive ties to the airframe.

  5. Energy efficient aircraft engines

    NASA Technical Reports Server (NTRS)

    Chamberlin, R.; Miller, B.

    1979-01-01

    The three engine programs that constitute the propulsion portion of NASA's Aircraft Energy Efficiency Program are described, their status indicated, and anticipated improvements in SFC discussed. The three engine programs are: (1) engine component improvement, directed at current engines, (2) energy efficient engine, directed at new turbofan engines, and (3) advanced turboprops, directed at technology for advanced turboprop-powered aircraft with cruise speeds to Mach 0.8. Unique propulsion system interactive ties to the airframe resulting from engine design features to reduce fuel consumption are discussed. Emphasis is placed on the advanced turboprop since it offers the largest potential fuel savings of the three propulsion programs and also has the strongest interactive ties to the airframe.

  6. Electrical Thermometers for Aircraft

    NASA Technical Reports Server (NTRS)

    Peterson, John B; Womack, S H J

    1937-01-01

    Electrical thermometers commonly used on aircraft are the thermoelectric type for measuring engine-cylinder temperatures, the resistance type for measuring air temperatures, and the superheat meters of thermoelectric and resistance types for use on airships. These instruments are described and their advantages and disadvantages enumerated. Methods of testing these instruments and the performance to be expected from each are discussed. The field testing of engine-cylinder thermometers is treated in detail.

  7. Slotted Aircraft Wing

    NASA Technical Reports Server (NTRS)

    McLean, James D. (Inventor); Witkowski, David P. (Inventor); Campbell, Richard L. (Inventor)

    2006-01-01

    A swept aircraft wing includes a leading airfoil element and a trailing airfoil element. At least one full-span slot is defined by the wing during at least one transonic condition of the wing. The full-span slot allows a portion of the air flowing along the lower surface of the leading airfoil element to split and flow over the upper surface of the trailing airfoil element so as to achieve a performance improvement in the transonic condition.

  8. Charge collection and SEU from angled ion strikes

    SciTech Connect

    Dodd, P.E.; Shaneyfelt, M.R.; Sexton, F.W.

    1997-03-01

    Single event upsets (SEUs) are caused in semiconductor microcircuits when charge is deposited in a sensitive volume of the circuit by an incident energetic particle. Collection of this charge causes a loss of information stored at the struck circuit node. Sensitive regions of a microcircuit typically consist of reverse-biased junctions which efficiently collect deposited charge through the influence of drift fields. During laboratory SEU testing, angled ion strikes are often used to conveniently mimic normally incident particles of higher linear energy transfer (LET). This practice is based on ion pathlengths through a thin rectangular parallelepiped (RPP) sensitive volume. Specifically, the authors assume that an angled strike deposits 1/cos{theta} more charge in the sensitive volume, which in turn is assumed to lead to 1/cos{theta} more charge collection at the sensitive node, and an increase in the particle`s effective LET to 1/cos{theta} higher than at normal incidence.

  9. Single Station System and Method of Locating Lightning Strikes

    NASA Technical Reports Server (NTRS)

    Medelius, Pedro J. (Inventor); Starr, Stanley O. (Inventor)

    2003-01-01

    An embodiment of the present invention uses a single detection system to approximate a location of lightning strikes. This system is triggered by a broadband RF detector and measures a time until the arrival of a leading edge of the thunder acoustic pulse. This time difference is used to determine a slant range R from the detector to the closest approach of the lightning. The azimuth and elevation are determined by an array of acoustic sensors. The leading edge of the thunder waveform is cross-correlated between the various acoustic sensors in the array to determine the difference in time of arrival, AT. A set of AT S is used to determine the direction of arrival, AZ and EL. The three estimated variables (R, AZ, EL) are used to locate a probable point of the lightning strike.

  10. Dynamic behavior of elevator compensating sheave during buffer strike

    NASA Astrophysics Data System (ADS)

    Watanabe, S.; Okawa, T.

    2016-05-01

    This paper shows an elevator dynamic model that calculates the compensating sheave motion during a buffer strike. Our equivalent 2-degree-of-freedom vibration model of an elevator system, which consists of a car, a compensating sheave, and compensating ropes, can evaluate the dynamic tension of the compensating ropes caused by a buffer strike. The constraint force, which restricts the upward motion of the compensating sheave, is estimated from the dynamic rope tension. The constraint force is represented by the summation of two vibration modes and is the function of the limited distance of the compensating sheave's upward movement. Our formula, which evaluates the maximum constraint force, shows that a shorter limited distance of the compensating sheave increases the constraint force.

  11. The influence of ice accretion physics on the forecasting of aircraft icing conditions

    NASA Technical Reports Server (NTRS)

    Hansman, R. John, Jr.

    1990-01-01

    The physics which control aircraft ice accretion are reviewed in the context of identifying and forecasting hazardous icing conditions. The severity of aircraft icing is found to be extremely sensitive to temperature, liquid water content and droplet size distribution particularly near the transition between rime and mixed icing. The difficulty in measurement and the variability of these factors with altitude, position and time coupled with variable aircraft sensitivity make forecasting and identifying icing conditions difficult. Automated Pilot Reports (PIREPS) are suggested as one mechanism for improving the data base necessary to forecast icing conditions.

  12. The influence of ice accretion physics on the forecasting of aircraft icing conditions

    NASA Technical Reports Server (NTRS)

    Hansman, R. John, Jr.

    1989-01-01

    The physics which control aircraft ice accretion are reviewed in the context of identifying and forecasting hazardous icing conditions. The severity of aircraft icing is found to be extremely sensitive to temperature, liquid water content and droplet size distribution particularly near the transition between rime and mixed icing. The difficulty in measurement and the variability of these factors with altitude, position and time coupled with variable aircraft sensitivity make forecasting and identifying icing conditions difficult. Automated Pilot Reports (PIREPS) are suggested as one mechanism for improving the data base necessary to forecast icing conditions.

  13. Hot-wire anemometry for in-flight measurement of aircraft wake vortices

    NASA Technical Reports Server (NTRS)

    Jacobsen, R. A.

    1977-01-01

    A development program has demonstrated that hot-wire anemometry can be used successfully on an aircraft in flight to make measurements of wake vortices produced by another aircraft. The probe, whose wires were made of platinum/rhodium, 10 microns in diameter, provides unambiguous results for inflow angles less than about 35 deg. off the probe axis. The high frequency response capability of the hot-wire system allows detailed measurement of the flow structure, and the study of aircraft hazards associated with wake turbulence.

  14. Hunt's 'sincere' words only strike a false note.

    PubMed

    Scott, Graham

    2014-10-21

    The first strike by NHS staff over pay in more than 30 years - and the first by members of the Royal College of Midwives in its history - will hopefully force ministers to rethink their decision to freeze pay rates for 1.3 million health service staff. Those taking part in Monday's four-hour stoppage and this week's 'work-to-rule' deserve great credit for making a sacrifice so that everyone in the NHS may benefit. PMID:25315522

  15. A sonic net excludes birds from an airfield: implications for reducing bird strike and crop losses.

    PubMed

    Swaddle, John P; Moseley, Dana L; Hinders, Mark K; Smith, Elizabeth P

    2016-03-01

    Collisions between birds and aircraft cause billions of dollars of damages annually to civil, commercial, and military aviation. Yet technology to reduce bird strike is not generally effective, especially over longer time periods. Previous information from our lab indicated that filling an area with acoustic noise, which masks important communication channels for birds, can displace European Starlings (Sturnus vulgaris) from food sources. Here we deployed a spatially controlled noise (termed a "sonic net"), designed to overlap with the frequency range of bird vocalizations, at an airfield. By conducting point counts, we monitored the presence of birds for four weeks before deployment of our sonic net, and for four weeks during deployment. We found an 82% reduction in bird presence in the sonic net area compared with change in the reference areas. This effect was as strong in the fourth week of exposure as in the first week. We also calculated the potential costs avoided resulting from this exclusion. We propose that spatially controlled acoustic manipulations that mask auditory communication for birds may be an effective long term and fairly benign way of excluding problem birds from areas of socioeconomic importance, such as airfields, agricultural sites, and commercial properties. PMID:27209777

  16. Cement mantle stress under retroversion torque at heel-strike.

    PubMed

    Afsharpoya, B; Barton, D C; Fisher, J; Purbach, B; Wroblewski, M; Stewart, T D

    2009-12-01

    The paper presents a theory of fixation failure and loosening in cemented total hip prostheses and proceeds to investigate this using an experimentally validated finite element model and two prosthesis types, namely the Charnley and the C-Stem. The study investigates the effects of retroversion torque occurring at heel-strike in combination with a loss of proximal cement/bone support and distal implant/cement support with a good distal cement/bone interface. A 3D finite element model was validated by comparison of femoral surface strains with those measured in an in vitro experimental simulation using an implanted Sawbone femur loaded in the heel-strike position and including a simplified representation of muscle forces. Results showed that the heel-strike position applies a high retroversion torque to the femoral stem that when combined with proximal debonding of the cement/bone interface and distal debonding of the implant/cement interface increases the strain transfer to the cement that may ultimately lead to the breakdown of the cement mantle leading on to osteolysis and loosening of the prostheses. Experimental fatigue testing of the implanted Charnley stem in a Sawbone femur produced cracks within the cement mantle that were located in positions of maximum stress supporting the finite element analysis results and theory of failure. PMID:19879794

  17. Distribution of strike-slip faults on Europa

    NASA Astrophysics Data System (ADS)

    Hoppa, Gregory; Greenberg, Richard; Tufts, B. Randall; Geissler, Paul; Phillips, Cynthia; Milazzo, Moses

    2000-09-01

    Study of four different regions on Europa imaged by the Galileo spacecraft during its first 15 orbits has revealed 117 strike-slip faults. Europa appears to form preferentially right-lateral faults in the southern hemisphere and left-lateral faults in the northern hemisphere. This observation is consistent with a model where diurnal tides due to orbital eccentricity drive strike-slip motion through a process of ``walking,'' in which faults open and close out of phase with alternating right-and left-lateral shear. Lineaments that record both left-and right-lateral motion (e.g., Agave Linea) may record the accommodation of compression in nearby chaotic zones. Nearly all identified strike-slip faults were associated with double ridges or bands, and few were detected along ridgeless cracks. Thus the depth of cracks without ridges does not appear to have penetrated to the low-viscosity decoupling layer, required for diurnal displacement, but cracks that have developed ridges do extend down to such a level. This result supports a model for ridge formation that requires cracks to penetrate to a decoupling layer, such as a liquid water ocean.

  18. The fast and forceful kicking strike of the secretary bird.

    PubMed

    Portugal, Steven J; Murn, Campbell P; Sparkes, Emily L; Daley, Monica A

    2016-01-25

    The study of animal locomotion has uncovered principles that can be applied to bio-inspired robotics, prosthetics and rehabilitation medicine, while also providing insight into musculoskeletal form and function [1-4]. In particular, study of extreme behaviors can reveal mechanical constraints and trade-offs that have influenced evolution of limb form and function [1,2]. Secretary birds (Sagittarius serpentarius; Figure 1A) are large terrestrial birds of prey endemic to sub-Saharan Africa, which feed on snakes, lizards and small mammals [5]. They frequently kick and stamp on the prey's head until it is killed or incapacitated, particularly when dispatching larger lizards and venomous snakes [5]. The consequences of a missed strike when hunting venomous snakes can be deadly [5], so the kicking strikes of secretary birds require fast yet accurate neural control. Delivery of fast, forceful and accurate foot strikes that are sufficient to stun and kill prey requires precision targeting, demanding a high level of coordination between the visual and neuromuscular systems. PMID:26811886

  19. Further identification and treatment modalities in telephone mediated lightning strike

    NASA Technical Reports Server (NTRS)

    Andrews, Christopher J.; Darveniza, Mat

    1991-01-01

    The results are presented of a prospective survey of people injured by lightning impulses transmitted by the public telephone system. The results are compared with those of a previous retrospective survey. Various deficiencies in the methodology of the latter survey are addressed. A division into a population with severe injury and a population with mild injury is made based on medical history and examination taken immediately after a strike. The best predictors of severe injury were found to be the presence of symptoms beyond one week after the strike, and also the initial presence of musculoskeletal injuries. Psychological upset is also seen to be a significant factor in severe injury. The only physical parameter of strike which could be used as a predictor of severe injury was the presence of concomitant power system damage. The importance of earth bonding between power and telephone system is thus supported in a protection strategy. One author draws on experience in treating patients with these injuries to propose a treatment regimen for those with ongoing symptoms. The importance of evaluating and treating psychological and physical aspects is stressed.

  20. Nucleation and growth of strike slip faults in granite.

    USGS Publications Warehouse

    Segall, P.; Pollard, D.P.

    1983-01-01

    Fractures within granodiorite of the central Sierra Nevada, California, were studied to elucidate the mechanics of faulting in crystalline rocks, with emphasis on the nucleation of new fault surfaces and their subsequent propagation and growth. Within the study area the fractures form a single, subparallel array which strikes N50o-70oE and dips steeply to the S. Some of these fractures are identified as joints because displacements across the fracture surfaces exhibit dilation but no slip. The joints are filled with undeformed minerals, including epidote and chlorite. Other fractures are identified as small faults because they display left-lateral strike slip separations of up to 2m. Slickensides, developed on fault surfaces, plunge 0o-20o to the E. The faults occur parallel to, and in the same outcrop with, the joints. The faults are filled with epidote, chlorite, and quartz, which exhibit textural evidence of shear deformation. These observations indicate that the strike slip faults nucleated on earlier formed, mineral filled joints. Secondary, dilational fractures propagated from near the ends of some small faults contemporaneously with the left-lateral slip on the faults. These fractures trend 25o+ or -10o from the fault planes, parallel to the direction of inferred local maximum compressive stress. The faults did not propagate into intact rock in their own planes as shear fractures. -from Authors

  1. Pattern of dynamic displacements in a strike-slip earthquake

    NASA Astrophysics Data System (ADS)

    Saltogianni, V.; Gianniou, M.; Moschas, F.; Stiros, S.

    2016-07-01

    High-rate (1 Hz) records from GPS stations uniformly distributed along the fault ruptures of the 2014 Samothraki-Gökçeada Mw6.9 earthquake in the North Aegean Trough, at the extension of the North Anatolian Fault Zone, were analyzed using the Precise Point Positioning (PPP) technique. Computed dynamic displacements shed light to the pattern of dynamic displacements during shallow strike-slip earthquakes. The area of near-field static seismic displacements bounds ramp-type, long-period dynamic displacements (fling steps) in the sense of static displacements. Along-fault and normal to fault components of dynamic displacement follow typical attenuation laws, but attenuation is higher in the fault-parallel component hence confined to the area of static dislocations. Forward directivity and local, especially topography-controlled amplification effects, consistent with accelerometer evidence, were also observed. The overall pattern seems to characterize shallow strike-slip earthquakes and is expected to prove useful to explain or even predict the near-field damaging potential of strike-slip earthquakes.

  2. Interaction of Aircraft Wakes From Laterally Spaced Aircraft

    NASA Technical Reports Server (NTRS)

    Proctor, Fred H.

    2009-01-01

    Large Eddy Simulations are used to examine wake interactions from aircraft on closely spaced parallel paths. Two sets of experiments are conducted, with the first set examining wake interactions out of ground effect (OGE) and the second set for in ground effect (IGE). The initial wake field for each aircraft represents a rolled-up wake vortex pair generated by a B-747. Parametric sets include wake interactions from aircraft pairs with lateral separations of 400, 500, 600, and 750 ft. The simulation of a wake from a single aircraft is used as baseline. The study shows that wake vortices from either a pair or a formation of B-747 s that fly with very close lateral spacing, last longer than those from an isolated B-747. For OGE, the inner vortices between the pair of aircraft, ascend, link and quickly dissipate, leaving the outer vortices to decay and descend slowly. For the IGE scenario, the inner vortices ascend and last longer, while the outer vortices decay from ground interaction at a rate similar to that expected from an isolated aircraft. Both OGE and IGE scenarios produce longer-lasting wakes for aircraft with separations less than 600 ft. The results are significant because concepts to increase airport capacity have been proposed that assume either aircraft formations and/or aircraft pairs landing on very closely spaced runways.

  3. Handling Hazardous Materials.

    ERIC Educational Resources Information Center

    Piper, James; Piverotto, John

    1990-01-01

    Describes a 16-hour course in hazard communication for vocational instructors, which teaches the proper use, storage, and disposal of hazardous materials in the laboratory as well as techniques for teaching safety. (SK)

  4. Household Hazards to Pets

    MedlinePlus

    ... health by becoming aware of the most common health hazards found in many pet-owning households. Hazards in the Kitchen Foods Many foods are perfectly safe for humans, but could be harmful or potentially deadly to ...

  5. Mission management aircraft operations manual

    NASA Technical Reports Server (NTRS)

    1992-01-01

    This manual prescribes the NASA mission management aircraft program and provides policies and criteria for the safe and economical operation, maintenance, and inspection of NASA mission management aircraft. The operation of NASA mission management aircraft is based on the concept that safety has the highest priority. Operations involving unwarranted risks will not be tolerated. NASA mission management aircraft will be designated by the Associate Administrator for Management Systems and Facilities. NASA mission management aircraft are public aircraft as defined by the Federal Aviation Act of 1958. Maintenance standards, as a minimum, will meet those required for retention of Federal Aviation Administration (FAA) airworthiness certification. Federal Aviation Regulation Part 91, Subparts A and B, will apply except when requirements of this manual are more restrictive.

  6. Lightning induced currents in aircraft wiring using low level injection techniques

    NASA Technical Reports Server (NTRS)

    Stevens, E. G.; Jordan, D. T.

    1991-01-01

    Various techniques were studied to predict the transient current induced into aircraft wiring bundles as a result of an aircraft lightning strike. A series of aircraft measurements were carried out together with a theoretical analysis using computer modeling. These tests were applied to various aircraft and also to specially constructed cylinders installed within coaxial return conductor systems. Low level swept frequency CW (carrier waves), low level transient and high level transient injection tests were applied to the aircraft and cylinders. Measurements were made to determine the transfer function between the aircraft drive current and the resulting skin currents and currents induced on the internal wiring. The full threat lightning induced transient currents were extrapolated from the low level data using Fourier transform techniques. The aircraft and cylinders used were constructed from both metallic and CFC (carbon fiber composite) materials. The results show the pulse stretching phenomenon which occurs for CFC materials due to the diffusion of the lightning current through carbon fiber materials. Transmission Line Matrix modeling techniques were used to compare theoretical and measured currents.

  7. Impact of aircraft plume dynamics on airport local air quality

    NASA Astrophysics Data System (ADS)

    Barrett, Steven R. H.; Britter, Rex E.; Waitz, Ian A.

    2013-08-01

    Air quality degradation in the locality of airports poses a public health hazard. The ability to quantitatively predict the air quality impacts of airport operations is of importance for assessing the air quality and public health impacts of airports today, of future developments, and for evaluating approaches for mitigating these impacts. However, studies such as the Project for the Sustainable Development of Heathrow have highlighted shortcomings in understanding of aircraft plume dispersion. Further, if national or international aviation environmental policies are to be assessed, a computationally efficient method of modeling aircraft plume dispersion is needed. To address these needs, we describe the formulation and validation of a three-dimensional integral plume model appropriate for modeling aircraft exhaust plumes at airports. We also develop a simplified concentration correction factor approach to efficiently account for dispersion processes particular to aircraft plumes. The model is used to explain monitoring station results in the London Heathrow area showing that pollutant concentrations are approximately constant over wind speeds of 3-12 m s-1, and is applied to reproduce empirically derived relationships between engine types and peak NOx concentrations at Heathrow. We calculated that not accounting for aircraft plume dynamics would result in a factor of 1.36-2.3 over-prediction of the mean NOx concentration (depending on location), consistent with empirical evidence of a factor of 1.7 over-prediction. Concentration correction factors are also calculated for aircraft takeoff, landing and taxi emissions, providing an efficient way to account for aircraft plume effects in atmospheric dispersion models.

  8. 14 CFR 43.7 - Persons authorized to approve aircraft, airframes, aircraft engines, propellers, appliances, or...

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ..., airframes, aircraft engines, propellers, appliances, or component parts for return to service after... FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT MAINTENANCE, PREVENTIVE MAINTENANCE, REBUILDING, AND ALTERATION § 43.7 Persons authorized to approve aircraft, airframes, aircraft...

  9. Aircraft cockpit vision: Math model

    NASA Technical Reports Server (NTRS)

    Bashir, J.; Singh, R. P.

    1975-01-01

    A mathematical model was developed to describe the field of vision of a pilot seated in an aircraft. Given the position and orientation of the aircraft, along with the geometrical configuration of its windows, and the location of an object, the model determines whether the object would be within the pilot's external vision envelope provided by the aircraft's windows. The computer program using this model was implemented and is described.

  10. Hazard function theory for nonstationary natural hazards

    NASA Astrophysics Data System (ADS)

    Read, Laura K.; Vogel, Richard M.

    2016-04-01

    Impact from natural hazards is a shared global problem that causes tremendous loss of life and property, economic cost, and damage to the environment. Increasingly, many natural processes show evidence of nonstationary behavior including wind speeds, landslides, wildfires, precipitation, streamflow, sea levels, and earthquakes. Traditional probabilistic analysis of natural hazards based on peaks over threshold (POT) generally assumes stationarity in the magnitudes and arrivals of events, i.e., that the probability of exceedance of some critical event is constant through time. Given increasing evidence of trends in natural hazards, new methods are needed to characterize their probabilistic behavior. The well-developed field of hazard function analysis (HFA) is ideally suited to this problem because its primary goal is to describe changes in the exceedance probability of an event over time. HFA is widely used in medicine, manufacturing, actuarial statistics, reliability engineering, economics, and elsewhere. HFA provides a rich theory to relate the natural hazard event series (X) with its failure time series (T), enabling computation of corresponding average return periods, risk, and reliabilities associated with nonstationary event series. This work investigates the suitability of HFA to characterize nonstationary natural hazards whose POT magnitudes are assumed to follow the widely applied generalized Pareto model. We derive the hazard function for this case and demonstrate how metrics such as reliability and average return period are impacted by nonstationarity and discuss the implications for planning and design. Our theoretical analysis linking hazard random variable X with corresponding failure time series T should have application to a wide class of natural hazards with opportunities for future extensions.

  11. Hazard function theory for nonstationary natural hazards

    NASA Astrophysics Data System (ADS)

    Read, L. K.; Vogel, R. M.

    2015-11-01

    Impact from natural hazards is a shared global problem that causes tremendous loss of life and property, economic cost, and damage to the environment. Increasingly, many natural processes show evidence of nonstationary behavior including wind speeds, landslides, wildfires, precipitation, streamflow, sea levels, and earthquakes. Traditional probabilistic analysis of natural hazards based on peaks over threshold (POT) generally assumes stationarity in the magnitudes and arrivals of events, i.e. that the probability of exceedance of some critical event is constant through time. Given increasing evidence of trends in natural hazards, new methods are needed to characterize their probabilistic behavior. The well-developed field of hazard function analysis (HFA) is ideally suited to this problem because its primary goal is to describe changes in the exceedance probability of an event over time. HFA is widely used in medicine, manufacturing, actuarial statistics, reliability engineering, economics, and elsewhere. HFA provides a rich theory to relate the natural hazard event series (X) with its failure time series (T), enabling computation of corresponding average return periods, risk and reliabilities associated with nonstationary event series. This work investigates the suitability of HFA to characterize nonstationary natural hazards whose POT magnitudes are assumed to follow the widely applied Generalized Pareto (GP) model. We derive the hazard function for this case and demonstrate how metrics such as reliability and average return period are impacted by nonstationarity and discuss the implications for planning and design. Our theoretical analysis linking hazard event series X, with corresponding failure time series T, should have application to a wide class of natural hazards with rich opportunities for future extensions.

  12. Hazard function theory for nonstationary natural hazards

    DOE PAGESBeta

    Read, Laura K.; Vogel, Richard M.

    2016-04-11

    Impact from natural hazards is a shared global problem that causes tremendous loss of life and property, economic cost, and damage to the environment. Increasingly, many natural processes show evidence of nonstationary behavior including wind speeds, landslides, wildfires, precipitation, streamflow, sea levels, and earthquakes. Traditional probabilistic analysis of natural hazards based on peaks over threshold (POT) generally assumes stationarity in the magnitudes and arrivals of events, i.e., that the probability of exceedance of some critical event is constant through time. Given increasing evidence of trends in natural hazards, new methods are needed to characterize their probabilistic behavior. The well-developed field ofmore » hazard function analysis (HFA) is ideally suited to this problem because its primary goal is to describe changes in the exceedance probability of an event over time. HFA is widely used in medicine, manufacturing, actuarial statistics, reliability engineering, economics, and elsewhere. HFA provides a rich theory to relate the natural hazard event series (X) with its failure time series (T), enabling computation of corresponding average return periods, risk, and reliabilities associated with nonstationary event series. This work investigates the suitability of HFA to characterize nonstationary natural hazards whose POT magnitudes are assumed to follow the widely applied generalized Pareto model. We derive the hazard function for this case and demonstrate how metrics such as reliability and average return period are impacted by nonstationarity and discuss the implications for planning and design. As a result, our theoretical analysis linking hazard random variable X with corresponding failure time series T should have application to a wide class of natural hazards with opportunities for future extensions.« less

  13. Hazardous Waste Roundup

    ERIC Educational Resources Information Center

    Farenga, Stephen J.; Joyce, Beverly A.; Ness, Daniel

    2004-01-01

    According to the Environmental Protection Agency (EPA), Americans generate approximately 1.6 million tons of hazardous household waste every year. When most people think of hazardous waste, they generally think of materials used in construction, the defense industry, mining, manufacturing, and agriculture. Few people think of hazardous substances…

  14. 19 CFR 122.64 - Other aircraft.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 19 Customs Duties 1 2014-04-01 2014-04-01 false Other aircraft. 122.64 Section 122.64 Customs... AIR COMMERCE REGULATIONS Clearance of Aircraft and Permission To Depart § 122.64 Other aircraft. Clearance or permission to depart shall be requested by the aircraft commander or agent for aircraft...

  15. 19 CFR 122.64 - Other aircraft.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 19 Customs Duties 1 2012-04-01 2012-04-01 false Other aircraft. 122.64 Section 122.64 Customs... AIR COMMERCE REGULATIONS Clearance of Aircraft and Permission To Depart § 122.64 Other aircraft. Clearance or permission to depart shall be requested by the aircraft commander or agent for aircraft...

  16. 19 CFR 122.64 - Other aircraft.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 19 Customs Duties 1 2013-04-01 2013-04-01 false Other aircraft. 122.64 Section 122.64 Customs... AIR COMMERCE REGULATIONS Clearance of Aircraft and Permission To Depart § 122.64 Other aircraft. Clearance or permission to depart shall be requested by the aircraft commander or agent for aircraft...

  17. 19 CFR 122.64 - Other aircraft.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 19 Customs Duties 1 2010-04-01 2010-04-01 false Other aircraft. 122.64 Section 122.64 Customs... AIR COMMERCE REGULATIONS Clearance of Aircraft and Permission To Depart § 122.64 Other aircraft. Clearance or permission to depart shall be requested by the aircraft commander or agent for aircraft...

  18. Simulation investigation of the effect of the NASA Ames 80-by 120-foot wind tunnel exhaust flow on light aircraft operating in the Moffett field trafffic pattern

    NASA Technical Reports Server (NTRS)

    Streeter, Barry G.

    1986-01-01

    A preliminary study of the exhaust flow from the Ames Research Center 80 by 120 Foot Wind Tunnel indicated that the flow might pose a hazard to low-flying light aircraft operating in the Moffett Field traffic pattern. A more extensive evaluation of the potential hazard was undertaken using a fixed-base, piloted simulation of a light, twin-engine, general-aviation aircraft. The simulated aircraft was flown through a model of the wind tunnel exhaust by pilots of varying experience levels to develop a data base of aircraft and pilot reactions. It is shown that a light aircraft would be subjected to a severe disturbance which, depending upon entry condition and pilot reaction, could result in a low-altitude stall or cause damage to the aircraft tail structure.

  19. Aircraft Low Altitude Wind Shear Detection and Warning System.

    NASA Astrophysics Data System (ADS)

    Sinclair, Peter C.; Kuhn, Peter M.

    1991-01-01

    There is now considerable evidence to substantiate the causal relationship between low altitude wind shear (LAWS) and the recent increase in low-altitude aircraft accidents. The National Research Council has found that for the period 1964 to 1982, LAWS was involved in nearly all the weather-related air carrier fatalities. However, at present, there is no acceptable method, technique, or hardware system that provides the necessary safety margins, for spatial and timely detection of LAWS from an aircraft during the critical phases of landing and takeoff. The Federal Aviation Administration (FAA) has addressed this matter and supports the development of an airborne system for detecting hazardous LAWS with at least a one minute warning of the potential hazard to the pilot. One of the purposes of this paper is to show from some of our preliminary flight measurement research that a forward looking infrared radiometer (FLIR) system can be used to successfully detect the cool downdraft of downbursts [microbursts/macrobursts (MB)] and thunderstorm gust front outflows that are responsible for most of the LAWS events. The FLIR system provides a much greater safety margin for the pilot than that provided by reactive designs such as inertial-air speed systems that require the actual penetration of the MB before a pilot warning can be initiated. Our preliminary results indicate that an advanced airborne FLIR system could provide the pilot with remote indication of MB threat, location, movement, and predicted MB hazards along the flight path ahead of the aircraft.In a proof-of-concept experiment, we have flight tested a prototype FLIR system (nonscanning, fixed range) near and within Colorado MBs with excellent detectability. The results show that a minimum warning time of one-four minutes (5×10 km), depending on aircraft speed, is available to the pilot prior to a MB encounter. Analysis of the flight data with respect to a modified `hazard index' indicates the severe hazard

  20. Broadband electromagnetic sensors for aircraft lightning research. [electromagnetic effects of lightning on aircraft digital equipment

    NASA Technical Reports Server (NTRS)

    Trost, T. F.; Zaepfel, K. P.

    1980-01-01

    A set of electromagnetic sensors, or electrically-small antennas, is described. The sensors are designed for installation on an F-106 research aircraft for the measurement of electric and magnetic fields and currents during a lightning strike. The electric and magnetic field sensors mount on the aircraft skin. The current sensor mounts between the nose boom and the fuselage. The sensors are all on the order of 10 cm in size and should produce up to about 100 V for the estimated lightning fields. The basic designs are the same as those developed for nuclear electromagnetic pulse studies. The most important electrical parameters of the sensors are the sensitivity, or equivalent area, and the bandwidth (or rise time). Calibration of sensors with simple geometries is reliably accomplished by a geometric analysis; all the sensors discussed possess geometries for which the sensitivities have been calculated. For the calibration of sensors with more complex geometries and for general testing of all sensors, two transmission lines were constructed to transmit known pulsed fields and currents over the sensors.

  1. The Typical General Aviation Aircraft

    NASA Technical Reports Server (NTRS)

    Turnbull, Andrew

    1999-01-01

    The reliability of General Aviation aircraft is unknown. In order to "assist the development of future GA reliability and safety requirements", a reliability study needs to be performed. Before any studies on General Aviation aircraft reliability begins, a definition of a typical aircraft that encompasses most of the general aviation characteristics needs to be defined. In this report, not only is the typical general aviation aircraft defined for the purpose of the follow-on reliability study, but it is also separated, or "sifted" into several different categories where individual analysis can be performed on the reasonably independent systems. In this study, the typical General Aviation aircraft is a four-place, single engine piston, all aluminum fixed-wing certified aircraft with a fixed tricycle landing gear and a cable operated flight control system. The system breakdown of a GA aircraft "sifts" the aircraft systems and components into five categories: Powerplant, Airframe, Aircraft Control Systems, Cockpit Instrumentation Systems, and the Electrical Systems. This breakdown was performed along the lines of a failure of the system. Any component that caused a system to fail was considered a part of that system.

  2. Intelligent aircraft/airspace systems

    NASA Technical Reports Server (NTRS)

    Wangermann, John P.

    1995-01-01

    Projections of future air traffic predict at least a doubling of the number of revenue passenger miles flown by the year 2025. To meet this demand, an Intelligent Aircraft/Airspace System (IAAS) has been proposed. The IAAS operates on the basis of principled negotiation between intelligent agents. The aircraft/airspace system today consists of many agents, such as airlines, control facilities, and aircraft. All the agents are becoming increasingly capable as technology develops. These capabilities should be exploited to create an Intelligent Aircraft/Airspace System (IAAS) that would meet the predicted traffic levels of 2005.

  3. Scheduling of an aircraft fleet

    NASA Technical Reports Server (NTRS)

    Paltrinieri, Massimo; Momigliano, Alberto; Torquati, Franco

    1992-01-01

    Scheduling is the task of assigning resources to operations. When the resources are mobile vehicles, they describe routes through the served stations. To emphasize such aspect, this problem is usually referred to as the routing problem. In particular, if vehicles are aircraft and stations are airports, the problem is known as aircraft routing. This paper describes the solution to such a problem developed in OMAR (Operative Management of Aircraft Routing), a system implemented by Bull HN for Alitalia. In our approach, aircraft routing is viewed as a Constraint Satisfaction Problem. The solving strategy combines network consistency and tree search techniques.

  4. NASA research in aircraft propulsion

    NASA Technical Reports Server (NTRS)

    Beheim, M. A.

    1982-01-01

    A broad overview of the scope of research presently being supported by NASA in aircraft propulsion is presented with emphasis on Lewis Research Center activities related to civil air transports, CTOL and V/STOL systems. Aircraft systems work is performed to identify the requirements for the propulsion system that enhance the mission capabilities of the aircraft. This important source of innovation and creativity drives the direction of propulsion research. In a companion effort, component research of a generic nature is performed to provide a better basis for design and provides an evolutionary process for technological growth that increases the capabilities of all types of aircraft. Both are important.

  5. Fire prevention on aircraft

    NASA Technical Reports Server (NTRS)

    Kuhn, Fritz

    1931-01-01

    The following discussion is at first restricted to the light-oil engines now in use. We shall consider how far it is possible to reduce fire hazards by changes in the design of the engines and carburetors and in the arrangement of the fuel pipes.

  6. 14 CFR 21.6 - Manufacture of new aircraft, aircraft engines, and propellers.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 14 Aeronautics and Space 1 2012-01-01 2012-01-01 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...

  7. 14 CFR 21.6 - Manufacture of new aircraft, aircraft engines, and propellers.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 14 Aeronautics and Space 1 2013-01-01 2013-01-01 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...

  8. 14 CFR 21.6 - Manufacture of new aircraft, aircraft engines, and propellers.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 14 Aeronautics and Space 1 2011-01-01 2011-01-01 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...

  9. 14 CFR 21.6 - Manufacture of new aircraft, aircraft engines, and propellers.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 14 Aeronautics and Space 1 2014-01-01 2014-01-01 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...

  10. 14 CFR 21.6 - Manufacture of new aircraft, aircraft engines, and propellers.

    Code of Federal Regulations, 2010 CFR

    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...

  11. National Unmanned Aircraft Systems Project Office

    USGS Publications Warehouse

    Goplen, Susan E.; Sloan, Jeff L.

    2015-01-01

    The U.S. Geological Survey (USGS) National Unmanned Aircraft Systems (UAS) Project Office leads the implementation of UAS technology in the Department of the Interior (DOI). Our mission is to support the transition of UAS into DOI as a new cost-effective tool for collecting remote-sensing data to monitor environmental conditions, respond to natural hazards, recognize the consequences and benefits of land and climate change and conduct wildlife inventories. The USGS is teaming with all DOI agencies and academia as well as local, State, and Tribal governments with guidance from the Federal Aviation Administration and the DOI Office of Aviation Services (OAS) to lead the safe, efficient, costeffective and leading-edge adoption of UAS technology into the scientific research and operational activities of the DOI.

  12. Aircraft surface coatings

    NASA Technical Reports Server (NTRS)

    1983-01-01

    A series of studies in which films and liquid spray-on materials were evaluated in the laboratory for transport aircraft external surface coatings are summarized. Elastomeric polyurethanes were found to best meet requirements. Two commercially available products, CAAPCO B-274 and Chemglaze M313, were subjected to further laboratory testing, airline service evaluations, and drag-measurement flight tests. It was found that these coatings were compatible with the severe operating environment of airlines and that coatings reduced airplane drag. An economic analysis indicated significant dollar benefits to airlines from application of the coatings.

  13. Aircraft Speed Instruments

    NASA Technical Reports Server (NTRS)

    Beij, K Hilding

    1933-01-01

    This report presents a concise survey of the measurement of air speed and ground speed on board aircraft. Special attention is paid to the pitot-static air-speed meter which is the standard in the United States for airplanes. Air-speed meters of the rotating vane type are also discussed in considerable detail on account of their value as flight test instruments and as service instruments for airships. Methods of ground-speed measurement are treated briefly, with reference to the more important instruments. A bibliography on air-speed measurement concludes the report.

  14. Structural integrity in aircraft.

    NASA Technical Reports Server (NTRS)

    Hardrath, H. F.

    1973-01-01

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

  15. Hydrogen aircraft technology

    NASA Technical Reports Server (NTRS)

    Brewer, G. D.

    1991-01-01

    A comprehensive evaluation is conducted of the technology development status, economics, commercial feasibility, and infrastructural requirements of LH2-fueled aircraft, with additional consideration of hydrogen production, liquefaction, and cryostorage methods. Attention is given to the effects of LH2 fuel cryotank accommodation on the configurations of prospective commercial transports and military airlifters, SSTs, and HSTs, as well as to the use of the plentiful heatsink capacity of LH2 for innovative propulsion cycles' performance maximization. State-of-the-art materials and structural design principles for integral cryotank implementation are noted, as are airport requirements and safety and environmental considerations.

  16. Slotted Aircraft Wing

    NASA Technical Reports Server (NTRS)

    Vassberg, John C. (Inventor); Gea, Lie-Mine (Inventor); McLean, James D. (Inventor); Witowski, David P. (Inventor); Krist, Steven E. (Inventor); Campbell, Richard L. (Inventor)

    2006-01-01

    An aircraft wing includes a leading airfoil element and a trailing airfoil element. At least one slot is defined by the wing during at least one transonic condition of the wing. The slot may either extend spanwise along only a portion of the wingspan, or it may extend spanwise along the entire wingspan. In either case, the slot allows a portion of the air flowing along the lower surface of the leading airfoil element to split and flow over the upper surface of the trailing airfoil element so as to achieve a performance improvement in the transonic condition.

  17. Noise: combating a ubiquitous and hazardous pollutant.

    PubMed

    Bronzaft, Arline L.

    2000-01-01

    With a growing body of data suggesting a link between noise and adverse mental and physical health and with noise pollution becoming even more pervasive, especially from the rapid increase in air travel and highway traffic, individuals worldwide are forging alliances to combat this hazardous pollutant. Especially active are the anti-aircraft noise groups. In the United States, the federal government has limited its responsibilities with respect to noise control after an initial interest in the 1970s when legislation was passed promising to protect the American people against the harmful effects of noise. These past years anti-noise activists in the United States have been working arduously to urge the federal government to once again take an active role in abating and controlling noise. They have also been enlisting more citizens to their cause as they educate them to the hazards of noise. PMID:12689475

  18. Automated Hazard Analysis

    2003-06-26

    The Automated Hazard Analysis (AHA) application is a software tool used to conduct job hazard screening and analysis of tasks to be performed in Savannah River Site facilities. The AHA application provides a systematic approach to the assessment of safety and environmental hazards associated with specific tasks, and the identification of controls regulations, and other requirements needed to perform those tasks safely. AHA is to be integrated into existing Savannah River site work control andmore » job hazard analysis processes. Utilization of AHA will improve the consistency and completeness of hazard screening and analysis, and increase the effectiveness of the work planning process.« less

  19. Final results of the NASA storm hazards program

    NASA Technical Reports Server (NTRS)

    Fisher, Bruce D.; Brown, Philip W.; Plumer, J. Anderson; Wunschel, Alfred J., Jr.

    1988-01-01

    Lightning swept-flash attachment patterns and the associated flight conditions were recorded from 1980-1986 during 1496 thunderstorm penetrations and 714 direct strikes with a NASA F-1068 research airplane. These data were studied with an emphasis on lightning avoidance by aircraft and on aircraft protection design. The individual lightning attachment spots, along with crew comments and on-board photographic data were used to identify lightning swept-flash attachment patterns and the orientations of the lightning channels with respect to the airplane. The full-scale in-flight data were compared to results from scale-model arc-attachment tests. The airborne and scale-model data showed that any exterior surface of this airplane may be susceptible to direct lightning attachment. In addition, the altitudes, ambient temperatures, and the relative turbulence and precipitation levels at which the strikes occurred in thunderstorms are summarized and discussed. It was found that the peak strike rate occurred at pressure altitudes betwen 38,000 ft and 40,000 ft, corresponding to ambient temperatures colder than -40 C.

  20. In-Flight Lightning Measurements and Reconstruction on a Metallic and Composite Aircraft

    NASA Astrophysics Data System (ADS)

    Boiddin, J.-F.; Flourens, F.; De Boer, A.; Bardet, M.; Herve, A.; Perez, G.; Riccio, L.

    2012-05-01

    Based on the success of the In-flight Lightning Strike Damage Assessment System (ILDAS) project launched within the scope of the Sixth Framework Programme of the European Commission and completed in July 2009, the results described in this paper form part of the ILDAS2 project initiated by Airbus Operations SAS in partnership with EADS IW and NLR. The principle aim of ILDAS2 project is to develop a system installed aboard an aircraft in order to determine the level, the current waveform and the attachments points of a lightning strike during an aircraft flight. The expectations linked to ILDAS2, the functional architecture of the system, the status and the projection of this development will be presented.

  1. Aircraft Inspection for the General Aviation Aircraft Owner.

    ERIC Educational Resources Information Center

    Federal Aviation Administration (DOT), Washington, DC. Flight Standards Service.

    Presented is useful information for owners, pilots, student mechanics, and others with aviation interests. Part I of this booklet outlines aircraft inspection requirements, owner responsibilities, inspection time intervals, and sources of basic information. Part II is concerned with the general techniques used to inspect an aircraft. (Author/JN)

  2. Hazard Analysis Database Report

    SciTech Connect

    GRAMS, W.H.

    2000-12-28

    The Hazard Analysis Database was developed in conjunction with the hazard analysis activities conducted in accordance with DOE-STD-3009-94, Preparation Guide for U S . Department of Energy Nonreactor Nuclear Facility Safety Analysis Reports, for HNF-SD-WM-SAR-067, Tank Farms Final Safety Analysis Report (FSAR). The FSAR is part of the approved Authorization Basis (AB) for the River Protection Project (RPP). This document describes, identifies, and defines the contents and structure of the Tank Farms FSAR Hazard Analysis Database and documents the configuration control changes made to the database. The Hazard Analysis Database contains the collection of information generated during the initial hazard evaluations and the subsequent hazard and accident analysis activities. The Hazard Analysis Database supports the preparation of Chapters 3 ,4 , and 5 of the Tank Farms FSAR and the Unreviewed Safety Question (USQ) process and consists of two major, interrelated data sets: (1) Hazard Analysis Database: Data from the results of the hazard evaluations, and (2) Hazard Topography Database: Data from the system familiarization and hazard identification.

  3. Preliminary Earthquake Hazard Map of Afghanistan

    USGS Publications Warehouse

    Boyd, Oliver S.; Mueller, Charles S.; Rukstales, Kenneth S.

    2007-01-01

    Introduction Earthquakes represent a serious threat to the people and institutions of Afghanistan. As part of a United States Agency for International Development (USAID) effort to assess the resource potential and seismic hazards of Afghanistan, the Seismic Hazard Mapping group of the United States Geological Survey (USGS) has prepared a series of probabilistic seismic hazard maps that help quantify the expected frequency and strength of ground shaking nationwide. To construct the maps, we do a complete hazard analysis for each of ~35,000 sites in the study area. We use a probabilistic methodology that accounts for all potential seismic sources and their rates of earthquake activity, and we incorporate modeling uncertainty by using logic trees for source and ground-motion parameters. See the Appendix for an explanation of probabilistic seismic hazard analysis and discussion of seismic risk. Afghanistan occupies a southward-projecting, relatively stable promontory of the Eurasian tectonic plate (Ambraseys and Bilham, 2003; Wheeler and others, 2005). Active plate boundaries, however, surround Afghanistan on the west, south, and east. To the west, the Arabian plate moves northward relative to Eurasia at about 3 cm/yr. The active plate boundary trends northwestward through the Zagros region of southwestern Iran. Deformation is accommodated throughout the territory of Iran; major structures include several north-south-trending, right-lateral strike-slip fault systems in the east and, farther to the north, a series of east-west-trending reverse- and strike-slip faults. This deformation apparently does not cross the border into relatively stable western Afghanistan. In the east, the Indian plate moves northward relative to Eurasia at a rate of about 4 cm/yr. A broad, transpressional plate-boundary zone extends into eastern Afghanistan, trending southwestward from the Hindu Kush in northeast Afghanistan, through Kabul, and along the Afghanistan-Pakistan border

  4. Lidar wind shear detection for commercial aircraft

    NASA Astrophysics Data System (ADS)

    Targ, Russell; Bowles, Roland L.

    1991-08-01

    National attention has focused on the critical problem of detecting and avoiding windshear since the crash on August 2, 1985, of a Lockheed L-1011 at Dallas/Fort Worth International Airport. As part of The NASA/FAA National Integrated Windshear Program, the authors have defined a measurable windshear hazard index that can be remotely sensed from an aircraft, to give the pilot information about the wind conditions he will experience at some later time if he continues along the present flight path. The technology analysis and end- to-end performance simulation, which measures signal-to-noise ratios and resulting wind velocity errors for competing coherent lidar systems, shows that a Ho:YAG lidar at a wavelength of 2.1 micrometers and a CO2 lidar at 10.6 micrometers can give the pilot information about the line-of-sight component of a windshear threat in a region extending from his present position to 2 to 4 km in front of the aircraft. This constitutes a warning time of 20 to 40 s, even under conditions of moderately heavy precipitation. Using these results, a Coherent Lidar Airborne Shear Sensor (CLASS), using a Q-switched CO2 laser at 10.6 micrometers , is being designed and developed for flight evaluation in early 1992.

  5. Jelly Quakes - Characteristics of periodic slip events in an analog model of strike slip seismotectonics using ballistic gelatin.

    NASA Astrophysics Data System (ADS)

    Rudolf, Michael; Rosenau, Matthias; Oncken, Onno

    2016-04-01

    Large lithospheric strike-slip faults, such as the San-Andreas Fault, North-Anatolian Fault, or the Tancheng-Lujiang Faultzone, are major sources of seismic hazard. The interplay of complex 3D-geometry and displacement style along the fault, coupled with a varying rheological layering makes it very difficult to model these faults on all relevant timescales. Here we present a novel experimental approach to model intra- and interplate strike-slip faults using a physical/ analog model. We model earthquakes as a stick-slip process, following a rate-and-state frictional law, with glass beads as granular material within a molded fault zone. Crustal elasticity is introduced by using ballistic gelatin (30 w%, pig skin) as analog material. Furthermore, the low-strength and viscous deep crust below 15 km depth, is modeled using a viscoelastic silicone oil (PDMS-G30M). The layered model crust floats on sugar syrup and is compressed in pure shear vice configuration. We monitor the compressive force along with surface kinematics from optical image correlation. The fault is oriented at 45° to the compression direction imposing ideal strike-slip kinematics onto it. After an initial loading phase the model shows periodic slip events occurring alongside with creep on the fault. Using digital image correlation, surface displacement maps are obtained which are similar to those of natural earthquakes. Coseismic displacement along strike is showing a similar bell-shaped distribution as for natural faults. Furthermore, the recurrence intervals and stress drops are scalable to the natural prototype. The modeling results are combined with numerical rate-and-state models using physical parameters from the experiment. This enables us to explore a wide range of parameters and to draw connections between the parameters that control the behavior of seismic and aseismic fault systems.

  6. Along Strike Heterogeneity of Seismic Slip Revealed by Oceanic Transform Fault Earthquakes

    NASA Astrophysics Data System (ADS)

    Aderhold, K.; Abercrombie, R. E.

    2015-12-01

    Oceanic transform faults (OTFs) are considered to have relatively simple structure [thermal, geometric, compositional], with the brittle-ductile transition defined by the 600-800ºC isotherm. Earthquakes on these faults account for less than half of the expected slip (Boettcher & Jordan, 2004), leaving the majority of motion to be accommodated aseismically. The 2015 MW7.1 Charlie-Gibbs transform earthquake is the latest of seven large [M≥6.25] earthquakes that form two quasi-repeating sequences dating back to 1920. These two sequences are separated by a region of persistent aseismicity in the center of the transform, interpreted to be a rupture barrier that prevents the full extent of the transform from rupturing in a single earthquake. However, aseismic rupture barriers alone cannot account for the inferred deficit in the seismic budget of OTFs. A growing catalogue of slip distributions has revealed distinctive behavior for large OTF earthquakes. We present evidence from teleseismic body wave modeling for directivity and slip distribution of four MW ≥ 7.0 oceanic strike-slip earthquakes: the 2015 MW7.1 Charlie-Gibbs transform earthquake in the North Atlantic, the 2015 MW7.0 Fourier transform earthquake in the South Atlantic, and the 2013 MW7.3 and 2006 MW7.4 South Sandwich transform earthquakes in the Southern Ocean. Each earthquake initiates near the ridge with nominal slip then propagates unilaterally to rupture larger asperities nearer the middle of the transform, similar to behavior observed for the 1994 MW7.0 Romanche transform earthquake. Significant continental strike-slip earthquakes, such as the 2002 MW7.9 Denali earthquake and the 2001 MW7.8 Kunlun earthquake, also exhibit unilateral ruptures with a small initial slip. The slip distributions of large oceanic transform earthquakes suggest that seismic coupling of OTFs varies considerably along strike, with large slip asperities separated by areas of little or no slip. Substantial earthquakes are not

  7. Along-strike translation of a fossil slab

    NASA Astrophysics Data System (ADS)

    Eichenbaum-Pikser, J. M.; Forsyth, D. W.; Hirth, G.

    2011-12-01

    The Isabella anomaly is a high seismic velocity anomaly beneath the southern Central Valley of California. Breaking from previous interpretations of the anomaly as a lithospheric drip (Zandt and Carrigan, 1993) or delaminated Sierra Nevada root (Zandt et al., 2004), Forsyth et al. (2011) propose that it is a remnant slab, left over from Cenozoic subduction, attached to the Monterey microplate and translating along-strike with the Pacific plate underneath the edge of the North American plate. This hypothesis requires the slab to translate hundreds of kilometers along strike while remaining intact and attached to the Pacific plate despite drag from the surrounding asthenosphere and overriding lithosphere. Using COMSOL Multiphysics, we design 3-D finite element fluid flow models to simulate this scenario, and calculate the viscosity ratio required between the slab and the surrounding asthenosphere in order for the slab to translate undeformed. The ratio needed increases with downdip extent of the slab, and decreases with slab dip; for geometries approximating that of our proposed slab, it ranges from 10^2 to 10^4. Given the thermal and hydrological history of the slab, mantle flow laws predict viscosity contrasts greater than or equal to these requirements. As such, we conclude that along-strike translation of a remnant slab is entirely feasible, and serves as possible explanation of the Isabella anomaly. The significance of this finding extends beyond our general understanding of subduction dynamics, in that the presence of such a slab could have interesting implications for the water budget of the San Andreas Fault and its role in aseismic slip.

  8. Pericollisional strike-slip basins in western Cordillera, Canada

    SciTech Connect

    Eisbacher, G.H.

    1984-04-01

    The late Mesozoic-Paleogene evolution of the Canadian Cordillera was dominated by accretion of elongate crustal blocks against the North American craton. Geologic and paleomagnetic evidence suggest that these exotic terranes dispersed from volcanic arcs and oceanic platforms and approached North America along anastomosing right-lateral faults with great cumulative displacement. Obduction of oceanic allochthons was followed by transpressive thickening and regional metamorphism of the cratonic margin in the mid-Jurassic. Strike-slip motion and emplacement of plutonic rocks continued near relict sutures and reactivated deep faults. Sedimentary basins related to strike-slip faults formed by elongation of accreted terranes (''Stikinia'' and ''Wrangellia'') and by shear within the deformed cratonic margin zone (''Rocky Mountain Trench''). Subsidence is reflected by northwest-southeast stretching along pull-apart structures, and by massive influx of turbidites from incipient collision zones and relict are relief. It was interrupted and outlived by rotation of blocks, folding of basin sediments, and vigorous progradation of deltaic-fluvial clastics from rising collision belts. Transition from predominant transtension to prevailing transpression is diachronous from basin to basin. Near the Stikine-Wrangellia collision zone (Bowser basin), it occurred in the Late Jurassic; along the Stikine-Wrangellia border it occurred in the mid to Late Cretaceous. Only small nonmarine basins developed in the Rocky Mountain Trench system, which, in its southern-most part, was closed completely during Paleogene thrust faulting. The strike-slip basins of the western Canadian Cordillera were subject to high regional heat flow and also suffered from widespread intrusion of paleogene granitoids. Therefore, they are generally poor oil and gas prospects.

  9. Strike planning against a target base with a value structure

    SciTech Connect

    Chrzanowski, P.L.

    1992-04-21

    With the signing of the Strategic Arms Reduction Treaty (START) and, with the end of the Cold War, two questions arise. How large should force reductions be in a START-II accord How much can the major nuclear powers reduce their nuclear arms and still maintain strategic stability. The results of the analysis presented here are summarized by the following five statements: (1) In the development of target lists, it is important to prioritize. A standard approach is to identify a break-point in the list of installations, to target only those facilities that are above the break-point, and to assign as many weapons as necessary to key installations to achieve damage goals. As an alternative, a systematic method is suggested here that uses the concept of target value. First, an ordinal list of targets must be developed. Then, values can be assigned to targets in a way that leads to reasonable set of targeting priorities and to a useful figure of merit to assess strike effectiveness. (2) Two complementary observations can be made, based on an analysis of optimum attack tactics against a target base with a value structure: It is not practical to size the stockpile based on the number of targets in the target set because a small change in the damage goal for the strike results in large change to the required inventory. By prioritizing targets, it is possible to make large reductions in the force structure while causing only small reductions in the expected target value damaged. (3) Prudence dictates building into strike plans hedges against degraded weapon performance. (4) The impact of defenses on the required offensive inventory depends on details about the management of defensive systems. (5) If timely information can be obtained about damage to targets so that follow-on weapons can be allocated only to undamaged targets, the number of weapons required to achieve the specified damage coal can be reduced significantly.

  10. Strike planning against a target base with a value structure

    SciTech Connect

    Chrzanowski, P.L.

    1992-04-21

    With the signing of the Strategic Arms Reduction Treaty (START) and, with the end of the Cold War, two questions arise. How large should force reductions be in a START-II accord? How much can the major nuclear powers reduce their nuclear arms and still maintain strategic stability. The results of the analysis presented here are summarized by the following five statements: (1) In the development of target lists, it is important to prioritize. A standard approach is to identify a break-point in the list of installations, to target only those facilities that are above the break-point, and to assign as many weapons as necessary to key installations to achieve damage goals. As an alternative, a systematic method is suggested here that uses the concept of target value. First, an ordinal list of targets must be developed. Then, values can be assigned to targets in a way that leads to reasonable set of targeting priorities and to a useful figure of merit to assess strike effectiveness. (2) Two complementary observations can be made, based on an analysis of optimum attack tactics against a target base with a value structure: It is not practical to size the stockpile based on the number of targets in the target set because a small change in the damage goal for the strike results in large change to the required inventory. By prioritizing targets, it is possible to make large reductions in the force structure while causing only small reductions in the expected target value damaged. (3) Prudence dictates building into strike plans hedges against degraded weapon performance. (4) The impact of defenses on the required offensive inventory depends on details about the management of defensive systems. (5) If timely information can be obtained about damage to targets so that follow-on weapons can be allocated only to undamaged targets, the number of weapons required to achieve the specified damage coal can be reduced significantly.

  11. Dumbo heavy lifter aircraft

    NASA Technical Reports Server (NTRS)

    Riester, Peter; Ellis, Colleen; Wagner, Michael; Orren, Scott; Smith, Byron; Skelly, Michael; Zgraggen, Craig; Webber, Matt

    1992-01-01

    The world is rapidly changing from one with two military superpowers, with which most countries were aligned, to one with many smaller military powers. In this environment, the United States cannot depend on the availability of operating bases from which to respond to crises requiring military intervention. Several studies (e.g. the SAB Global Reach, Global Power Study) have indicated an increased need to be able to rapidly transport large numbers of troops and equipment from the continental United States to potential trouble spots throughout the world. To this end, a request for proposals (RFP) for the concept design of a large aircraft capable of 'projecting' a significant military force without reliance on surface transportation was developed. These design requirements are: minimum payload of 400,000 pounds at 2.5 g maneuver load factor; minimum unfueled range of 6,000 nautical miles; and aircraft must operate from existing domestic air bases and use existing airbases or sites of opportunity at the destination.

  12. Aircraft landing using GPS

    NASA Astrophysics Data System (ADS)

    Lawrence, David Gary

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

  13. Hypersonic transport aircraft

    NASA Technical Reports Server (NTRS)

    1987-01-01

    A hypersonic transport aircraft design project was selected as a result of interactions with NASA Lewis Research Center personnel and fits the Presidential concept of the Orient Express. The Graduate Teaching Assistant (GTA) and an undergraduate student worked at the NASA Lewis Research Center during the 1986 summer conducting a literature survey, and relevant literature and useful software were collected. The computer software was implemented in the Computer Aided Design Laboratory of the Mechanical and Aerospace Engineering Department. In addition to the lectures by the three instructors, a series of guest lectures was conducted. The first of these lectures 'Anywhere in the World in Two Hours' was delivered by R. Luidens of NASA Lewis Center. In addition, videotaped copies of relevant seminars obtained from NASA Lewis were also featured. The first assignment was to individually research and develop the mission requirements and to discuss the findings with the class. The class in consultation with the instructors then developed a set of unified mission requirements. Then the class was divided into three design groups (1) Aerodynamics Group, (2) Propulsion Group, and (3) Structures and Thermal Analyses Group. The groups worked on their respective design areas and interacted with each other to finally come up with an integrated conceptual design. The three faculty members and the GTA acted as the resource persons for the three groups and aided in the integration of the individual group designs into the final design of a hypersonic aircraft.

  14. Altus aircraft on runway

    NASA Technical Reports Server (NTRS)

    1996-01-01

    The remotely piloted Altus aircraft flew several developmental test flights from Rogers Dry Lake adjacent to NASA's Dryden Flight Research Center, Edwards, Calif., in 1996. The Altus--the word is Latin for 'high'--is a variant of the Predator surveillance drone built by General Atomics/Aeronautical Systems, Inc. It is designed for high-altitude, long-duration scientific sampling missions, and is powered by a turbocharged four-cylinder piston engine. The first Altus was developed under NASA's Environmental Research Aircraft and Sensor Technology program, while a second Altus was built for a Naval Postgraduate School/Department of Energy program. A pilot in a control station on the ground flew the craft by radio signals, using visual cues from a video camera in the nose of the Altus and information from the craft's air data system. Equipped with a single-stage turbocharger during the 1996 test flights, the first Altus reached altitudes in the 37,000-foot range, while the similarly-equipped second Altus reached 43,500 feet during developmental flights at Dryden in the summer of 1997. The NASA Altus also set an endurance record of more than 26 hours while flying a science mission in late 1996 and still had an estimated 10 hours of fuel remaining when it landed. Now equipped with a two-stage turbocharger, the NASA Altus maintained an altitude of 55,000 feet for four hours during flight tests in 1999.

  15. Biomechanics: deadly strike mechanism of a mantis shrimp.

    PubMed

    Patek, S N; Korff, W L; Caldwell, R L

    2004-04-22

    Stomatopods (mantis shrimp) are well known for the feeding appendages they use to smash shells and impale fish. Here we show that the peacock mantis shrimp (Odontodactylus scyllarus) generates an extremely fast strike that requires major energy storage and release, which we explain in terms of a saddle-shaped exoskeletal spring mechanism. High-speed images reveal the formation and collapse of vapour bubbles next to the prey due to swift movement of the appendage towards it, indicating that O. scyllarus may use destructive cavitation forces to damage its prey. PMID:15103366

  16. Steam Power Plants in Aircraft

    NASA Technical Reports Server (NTRS)

    Wilson, E E

    1926-01-01

    The employment of steam power plants in aircraft has been frequently proposed. Arguments pro and con have appeared in many journals. It is the purpose of this paper to make a brief analysis of the proposal from the broad general viewpoint of aircraft power plants. Any such analysis may be general or detailed.

  17. The Ultra Light Aircraft Testing

    NASA Technical Reports Server (NTRS)

    Smith, Howard W.

    1993-01-01

    The final report for grant NAG1-345 is presented. Recently, the bulk of the work that the grant has supported has been in the areas of ride quality and the structural analysis and testing of ultralight aircraft. The ride quality work ended in May 1989. Hence, the papers presented in this final report are concerned with ultralight aircraft.

  18. Aircraft wiring program status report

    NASA Technical Reports Server (NTRS)

    Beach, Rex

    1995-01-01

    In this Naval Air Warfare Center (NAWC) Aircraft Division status report, the general and wire and cable component activities, the systems engineering activities, the aircraft wiring lead maintenance activities, the NAVAIR/NASA interface activities, and the Base Realignment and Closure (BRAC) Commission recommendations are presented.

  19. Fuel conservative aircraft engine technology

    NASA Technical Reports Server (NTRS)

    Nored, D. L.

    1978-01-01

    Technology developments for more fuel-efficiency subsonic transport aircraft are reported. Three major propulsion projects were considered: (1) engine component improvement - directed at current engines; (2) energy efficient engine - directed at new turbofan engines; and (3) advanced turboprops - directed at technology for advanced turboprop-powered aircraft. Each project is reviewed and some of the technologies and recent accomplishments are described.

  20. Hazard index calculation for 31 May 1984 microburst at Erie, Colorado

    NASA Technical Reports Server (NTRS)

    Kropfli, R. A.

    1988-01-01

    Two x-band Doppler radars, operated by NOAA, were used to collect high resolution data within a small, benign looking microburst during the PHOENIX II boundary layer experiment. The lowest 2.5 km of the microbursts was observed throughout its development and dissipation over a 15 minute period. These observations presented an excellent opportunity to compute a quantitative threat to a hypothetical aircraft whose flight track would carry it through the microburst. The hazard index is based on the kinetic energy loss to the aircraft that would be produced by the microburst; it is a function of the vertical air motion, horizontal spatial derivatives of the wind field, and the assumed aircraft air speed and direction. Indices were computed and plotted for all 8 volume scans and peak values were observed to be sufficiently high to present a significant hazard to an aircraft.