Science.gov

Sample records for flight paths

  1. Aircraft flight path angle display system

    NASA Technical Reports Server (NTRS)

    Lambregts, Antonius A. (Inventor)

    1991-01-01

    A display system for use in an aircraft control wheel steering system provides the pilot with a single, quickened flight path angle display to overcome poor handling qualities due to intrinsic flight path angle response lags, while avoiding multiple information display symbology. The control law for the flight path angle control system is designed such that the aircraft's actual flight path angle response lags the pilot's commanded flight path angle by a constant time lag .tau., independent of flight conditions. The synthesized display signal is produced as a predetermined function of the aircraft's actual flight path angle, the time lag .tau. and command inputs from the pilot's column.

  2. Vertical flight path steering system for aircraft

    NASA Technical Reports Server (NTRS)

    Lambregts, Antonius A. (Inventor)

    1983-01-01

    Disclosed is a vertical flight path angle steering system for aircraft, utilizing a digital flight control computer which processes pilot control inputs and aircraft response parameters into suitable elevator commands and control information for display to the pilot on a cathode ray tube. The system yields desirable airplane control handling qualities and responses as well as improvements in pilot workload and safety during airplane operation in the terminal area and under windshear conditions.

  3. Planning Flight Paths of Autonomous Aerobots

    NASA Technical Reports Server (NTRS)

    Kulczycki, Eric; Elfes, Alberto; Sharma, Shivanjli

    2009-01-01

    Algorithms for planning flight paths of autonomous aerobots (robotic blimps) to be deployed in scientific exploration of remote planets are undergoing development. These algorithms are also adaptable to terrestrial applications involving robotic submarines as well as aerobots and other autonomous aircraft used to acquire scientific data or to perform surveying or monitoring functions.

  4. Optimum flight paths of turbojet aircraft

    NASA Technical Reports Server (NTRS)

    Miele, Angelo

    1955-01-01

    The climb of turbojet aircraft is analyzed and discussed including the accelerations. Three particular flight performances are examined: minimum time of climb, climb with minimum fuel consumption, and steepest climb. The theoretical results obtained from a previous study are put in a form that is suitable for application on the following simplifying assumptions: the Mach number is considered an independent variable instead of the velocity; the variations of the airplane mass due to fuel consumption are disregarded; the airplane polar is assumed to be parabolic; the path curvatures and the squares of the path angles are disregarded in the projection of the equation of motion on the normal to the path; lastly, an ideal turbojet with performance independent of the velocity is involved. The optimum Mach number for each flight condition is obtained from the solution of a sixth order equation in which the coefficients are functions of two fundamental parameters: the ratio of minimum drag in level flight to the thrust and the Mach number which represents the flight at constant altitude and maximum lift-drag ratio.

  5. Quad-rotor flight path energy optimization

    NASA Astrophysics Data System (ADS)

    Kemper, Edward

    Quad-Rotor unmanned areal vehicles (UAVs) have been a popular area of research and development in the last decade, especially with the advent of affordable microcontrollers like the MSP 430 and the Raspberry Pi. Path-Energy Optimization is an area that is well developed for linear systems. In this thesis, this idea of path-energy optimization is extended to the nonlinear model of the Quad-rotor UAV. The classical optimization technique is adapted to the nonlinear model that is derived for the problem at hand, coming up with a set of partial differential equations and boundary value conditions to solve these equations. Then, different techniques to implement energy optimization algorithms are tested using simulations in Python. First, a purely nonlinear approach is used. This method is shown to be computationally intensive, with no practical solution available in a reasonable amount of time. Second, heuristic techniques to minimize the energy of the flight path are tested, using Ziegler-Nichols' proportional integral derivative (PID) controller tuning technique. Finally, a brute force look-up table based PID controller is used. Simulation results of the heuristic method show that both reliable control of the system and path-energy optimization are achieved in a reasonable amount of time.

  6. Optimum Strategies for Selecting Descent Flight-Path Angles

    NASA Technical Reports Server (NTRS)

    Wu, Minghong G. (Inventor); Green, Steven M. (Inventor)

    2016-01-01

    An information processing system and method for adaptively selecting an aircraft descent flight path for an aircraft, are provided. The system receives flight adaptation parameters, including aircraft flight descent time period, aircraft flight descent airspace region, and aircraft flight descent flyability constraints. The system queries a plurality of flight data sources and retrieves flight information including any of winds and temperatures aloft data, airspace/navigation constraints, airspace traffic demand, and airspace arrival delay model. The system calculates a set of candidate descent profiles, each defined by at least one of a flight path angle and a descent rate, and each including an aggregated total fuel consumption value for the aircraft following a calculated trajectory, and a flyability constraints metric for the calculated trajectory. The system selects a best candidate descent profile having the least fuel consumption value while the fly ability constraints metric remains within aircraft flight descent flyability constraints.

  7. Optimized Flight Path for Localization Using Line of Bearing

    DTIC Science & Technology

    2015-03-26

    OPTIMIZED FLIGHT PATH FOR LOCALIZATION USING LINE OF BEARING THESIS Namkyu Kim, Captain, Republic of Korea AFIT-ENY-MS-15-M-246 DEPARTMENT OF THE AIR...limitations. AFIT-ENY-MS-15-M-246 OPTIMIZED FLIGHT PATH FOR LOCALIZATION USING LINE OF BEARING THESIS Presented to the Faculty Department of Aeronautics...LINE OF BEARING THESIS Namkyu Kim, BS Captain, Republic of Korea Committee Membership: Richard G. Cobb, PhD Chair David R. Jacques, PhD Member Matthew

  8. 14 CFR 25.115 - Takeoff flight path.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT AIRWORTHINESS STANDARDS: TRANSPORT CATEGORY AIRPLANES Flight Performance § 25.115 Takeoff flight path. (a) The takeoff... each point by a gradient of climb equal to— (1) 0.8 percent for two-engine airplanes; (2) 0.9...

  9. 14 CFR 25.115 - Takeoff flight path.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT AIRWORTHINESS STANDARDS: TRANSPORT CATEGORY AIRPLANES Flight Performance § 25.115 Takeoff flight path. (a) The takeoff... each point by a gradient of climb equal to— (1) 0.8 percent for two-engine airplanes; (2) 0.9...

  10. 14 CFR 25.115 - Takeoff flight path.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT AIRWORTHINESS STANDARDS: TRANSPORT CATEGORY AIRPLANES Flight Performance § 25.115 Takeoff flight path. (a) The takeoff... each point by a gradient of climb equal to— (1) 0.8 percent for two-engine airplanes; (2) 0.9...

  11. 14 CFR 25.115 - Takeoff flight path.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT AIRWORTHINESS STANDARDS: TRANSPORT CATEGORY AIRPLANES Flight Performance § 25.115 Takeoff flight path. (a) The takeoff... each point by a gradient of climb equal to— (1) 0.8 percent for two-engine airplanes; (2) 0.9...

  12. 14 CFR 25.115 - Takeoff flight path.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT AIRWORTHINESS STANDARDS: TRANSPORT CATEGORY AIRPLANES Flight Performance § 25.115 Takeoff flight path. (a) The takeoff... each point by a gradient of climb equal to— (1) 0.8 percent for two-engine airplanes; (2) 0.9...

  13. Efficiency Mode of Energy Management based on Optimal Flight Path

    NASA Astrophysics Data System (ADS)

    Yang, Ling-xiao

    2016-07-01

    One new method of searching the optimal flight path in target function is put forward, which is applied to energy section for reentry flight vehicle, and the optimal flight path in which the energy is managed to decline rapidly, is settled by this design. The research for energy management is meaningful for engineering, it can also improve the applicability and flexibility for vehicle. The angle-of-attack and the bank angle are used to regulate energy and range at unpowered reentry flight as control variables. Firstly, the angle-of-attack section for minimum lift-to-drag ratio is ensured by the relation of range and lift-to-drag ratio. Secondly, build the secure boundary for flight corridor by restrictions in flight. Thirdly, the D-e section is optimized for energy expending in corridor by the influencing rule of the D-e section and range. Finally, compare this design method with the traditional Pseudo-spectral method. Moreover, energy-managing is achieved by cooperating lateral motion, and the optimized D-e section is tracked to prove the practicability of programming flight path with energy management.

  14. Light airplane crash tests at three flight-path angles

    NASA Technical Reports Server (NTRS)

    Castle, C. B.; Alfaro-Bou, E.

    1978-01-01

    Three similar twin engine general aviation airplane specimens were crash tested at Langley impact dynamics research facility at 27 m/sec and at flight-path angles of -15 deg, -30 deg, and -45 deg. Other flight parameters were held constant. The test facility, instrumentation, test specimens, and test method are briefly described. Structural damage and accelerometer data for each of the three impact conditions are presented and discussed.

  15. 14 CFR 25.123 - En route flight paths.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... provides adequate cooling in the hot-day condition. (b) The one-engine-inoperative net flight path data...) In non-icing conditions; and (2) In icing conditions with the en route ice accretion defined in appendix C, if: (i) A speed of 1.18 “VSR0 with the en route ice accretion exceeds the en route...

  16. 14 CFR 25.123 - En route flight paths.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... provides adequate cooling in the hot-day condition. (b) The one-engine-inoperative net flight path data...) In non-icing conditions; and (2) In icing conditions with the en route ice accretion defined in appendix C, if: (i) A speed of 1.18 “VSR0 with the en route ice accretion exceeds the en route...

  17. 14 CFR 25.123 - En route flight paths.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... provides adequate cooling in the hot-day condition. (b) The one-engine-inoperative net flight path data...) In non-icing conditions; and (2) In icing conditions with the en route ice accretion defined in appendix C, if: (i) A speed of 1.18 “VSR0 with the en route ice accretion exceeds the en route...

  18. 14 CFR 25.123 - En route flight paths.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... provides adequate cooling in the hot-day condition. (b) The one-engine-inoperative net flight path data...) In non-icing conditions; and (2) In icing conditions with the en route ice accretion defined in appendix C, if: (i) A speed of 1.18 “VSR0 with the en route ice accretion exceeds the en route...

  19. 14 CFR 25.123 - En route flight paths.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... provides adequate cooling in the hot-day condition. (b) The one-engine-inoperative net flight path data...) In non-icing conditions; and (2) In icing conditions with the en route ice accretion defined in appendix C, if: (i) A speed of 1.18 “VSR0 with the en route ice accretion exceeds the en route...

  20. NACA Flight-Path Angle and Air-Speed Recorder

    NASA Technical Reports Server (NTRS)

    Coleman, Donald G

    1926-01-01

    A new trailing bomb-type instrument for photographically recording the flight-path angle and air speed of aircraft in unaccelerated flight is described. The instrument consists essentially of an inclinometer, air-speed meter and a film-drum case. The inclinometer carries an oil-damped pendulum which records optically the flight-path angle upon a rotating motor-driven film drum. The air-speed meter consists of a taut metal diaphragm of high natural frequency which is acted upon by the pressure difference of a Prandtl type Pitot-static tube. The inclinometer record and air-speed record are made optically on the same sensitive film. Two records taken by this instrument are shown.

  1. Flight-Path Characteristics for Decelerating From Supercircular Speed

    NASA Technical Reports Server (NTRS)

    Luidens, Roger W.

    1961-01-01

    Characteristics of the following six flight paths for decelerating from a supercircular speed are developed in closed form: constant angle of attack, constant net acceleration, constant altitude" constant free-stream Reynolds number, and "modulated roll." The vehicles were required to remain in or near the atmosphere, and to stay within the aerodynamic capabilities of a vehicle with a maximum lift-drag ratio of 1.0 and within a maximum net acceleration G of 10 g's. The local Reynolds number for all the flight paths for a vehicle with a gross weight of 10,000 pounds and a 600 swept wing was found to be about 0.7 x 10(exp 6). With the assumption of a laminar boundary layer, the heating of the vehicle is studied as a function of type of flight path, initial G load, and initial velocity. The following heating parameters were considered: the distribution of the heating rate over the vehicle, the distribution of the heat per square foot over the vehicle, and the total heat input to the vehicle. The constant G load path at limiting G was found to give the lowest total heat input for a given initial velocity. For a vehicle with a maximum lift-drag ratio of 1.0 and a flight path with a maximum G of 10 g's, entry velocities of twice circular appear thermo- dynamically feasible, and entries at velocities of 2.8 times circular are aerodynamically possible. The predominant heating (about 85 percent) occurs at the leading edge of the vehicle. The total ablated weight for a 10,000-pound-gross-weight vehicle decelerating from an initial velocity of twice circular velocity is estimated to be 5 percent of gross weight. Modifying the constant G load flight path by a constant-angle-of-attack segment through a flight- to circular-velocity ratio of 1.0 gives essentially a "point landing" capability but also results in an increased total heat input to the vehicle.

  2. Integrated flight path planning system and flight control system for unmanned helicopters.

    PubMed

    Jan, Shau Shiun; Lin, Yu Hsiang

    2011-01-01

    This paper focuses on the design of an integrated navigation and guidance system for unmanned helicopters. The integrated navigation system comprises two systems: the Flight Path Planning System (FPPS) and the Flight Control System (FCS). The FPPS finds the shortest flight path by the A-Star (A*) algorithm in an adaptive manner for different flight conditions, and the FPPS can add a forbidden zone to stop the unmanned helicopter from crossing over into dangerous areas. In this paper, the FPPS computation time is reduced by the multi-resolution scheme, and the flight path quality is improved by the path smoothing methods. Meanwhile, the FCS includes the fuzzy inference systems (FISs) based on the fuzzy logic. By using expert knowledge and experience to train the FIS, the controller can operate the unmanned helicopter without dynamic models. The integrated system of the FPPS and the FCS is aimed at providing navigation and guidance to the mission destination and it is implemented by coupling the flight simulation software, X-Plane, and the computing software, MATLAB. Simulations are performed and shown in real time three-dimensional animations. Finally, the integrated system is demonstrated to work successfully in controlling the unmanned helicopter to operate in various terrains of a digital elevation model (DEM).

  3. Geophysical flight line flying and flight path recovery utilizing the Litton LTN-76 inertial navigation system

    SciTech Connect

    Mitkus, A.F.; Cater, D.; Farmer, P.F.; Gay, S.P. Jr.

    1981-11-01

    The Litton LTN-76 Inertial Navigation Systems (INS) with Inertial Track guidance System (ITGS) software is geared toward the airborne survey industry. This report is a summary of tests performed with the LTN-76 designed to fly an airborne geophysical survey as well as to recover the subsequent flight path utilizing INS derived coordinates.

  4. The flight paths of honeybees recruited by the waggle dance.

    PubMed

    Riley, J R; Greggers, U; Smith, A D; Reynolds, D R; Menzel, R

    2005-05-12

    In the 'dance language' of honeybees, the dancer generates a specific, coded message that describes the direction and distance from the hive of a new food source, and this message is displaced in both space and time from the dancer's discovery of that source. Karl von Frisch concluded that bees 'recruited' by this dance used the information encoded in it to guide them directly to the remote food source, and this Nobel Prize-winning discovery revealed the most sophisticated example of non-primate communication that we know of. In spite of some initial scepticism, almost all biologists are now convinced that von Frisch was correct, but what has hitherto been lacking is a quantitative description of how effectively recruits translate the code in the dance into flight to their destinations. Using harmonic radar to record the actual flight paths of recruited bees, we now provide that description.

  5. Flight 20 (STS-45) polysulfide gas path investigation

    NASA Technical Reports Server (NTRS)

    Bjorkman, Rey C.; Bown, Charles W.; Smith, Scott D.; Walters, Jerry L.; Kulkarni, Suresh B.; Cook, Roger V.; Sebahar, David A.; Walker, Craig S.; Haddock, M. Reed; Lindstrom, Robert E.

    1992-01-01

    This report documents the results of the investigation into causes of gas paths on the 20A and 20B case-to-nozzle joints on STS-42. The investigation was conducted by the Investigation Board appointed by the senior vice president and general manager of Space Operations, Mr. R. E. Lindstrom, on 7 Feb. 1992. The probability of gas path occurrence in the nozzle-to-case-joint polysulfide had been identified during joint redesign. However, actual flight gas path incidence has been limited to RSRM-11 and the 20A and 20B segments. The blow-by condition on the 20A segment was a first time occurrence which was a special concern. The investigation covered all technical aspects associated with the gas path and blow-by conditions: materials and processing history, design requirements and as-built compliance to the design, thermal and structural analyses, computer modeling, and laboratory experimentation with the materials involved. The investigation was coordinated with Mr. Ken Jones at NASA Marshall in bi-weekly teleconferences. The Board also supported Dr. James C. Blair's independent NASA investigation team by providing copies of collected data, conducting requested analyses, and supporting several all-day teleconferences to provide understanding and resolve issues. The Dr. Blair support requirement was successfully concluded on 4 Mar. 1992.

  6. Enroute flight-path planning - Cooperative performance of flight crews and knowledge-based systems

    NASA Technical Reports Server (NTRS)

    Smith, Philip J.; Mccoy, Elaine; Layton, Chuck; Galdes, Deb

    1989-01-01

    Interface design issues associated with the introduction of knowledge-based systems into the cockpit are discussed. Such issues include not only questions about display and control design, they also include deeper system design issues such as questions about the alternative roles and responsibilities of the flight crew and the computer system. In addition, the feasibility of using enroute flight path planning as a context for exploring such research questions is considered. In particular, the development of a prototyping shell that allows rapid design and study of alternative interfaces and system designs is discussed.

  7. Modeled Impact of Cirrus Cloud Increases Along Aircraft Flight Paths

    NASA Technical Reports Server (NTRS)

    Rind, David; Lonergan, P.; Shah, K.

    1999-01-01

    The potential impact of contrails and alterations in the lifetime of background cirrus due to subsonic airplane water and aerosol emissions has been investigated in a set of experiments using the GISS GCM connected to a q-flux ocean. Cirrus clouds at a height of 12-15km, with an optical thickness of 0.33, were input to the model "x" percentage of clear-sky occasions along subsonic aircraft flight paths, where x is varied from .05% to 6%. Two types of experiments were performed: one with the percentage cirrus cloud increase independent of flight density, as long as a certain minimum density was exceeded; the other with the percentage related to the density of fuel expenditure. The overall climate impact was similar with the two approaches, due to the feedbacks of the climate system. Fifty years were run for eight such experiments, with the following conclusions based on the stable results from years 30-50 for each. The experiments show that adding cirrus to the upper troposphere results in a stabilization of the atmosphere, which leads to some decrease in cloud cover at levels below the insertion altitude. Considering then the total effect on upper level cloud cover (above 5 km altitude), the equilibrium global mean temperature response shows that altering high level clouds by 1% changes the global mean temperature by 0.43C. The response is highly linear (linear correlation coefficient of 0.996) for high cloud cover changes between 0. 1% and 5%. The effect is amplified in the Northern Hemisphere, more so with greater cloud cover change. The temperature effect maximizes around 10 km (at greater than 40C warming with a 4.8% increase in upper level clouds), again more so with greater warming. The high cloud cover change shows the flight path influence most clearly with the smallest warming magnitudes; with greater warming, the model feedbacks introduce a strong tropical response. Similarly, the surface temperature response is dominated by the feedbacks, and shows

  8. Flight path-driven mitigation of wavefront curvature effects in SAR images

    SciTech Connect

    Doerry, Armin W.

    2009-06-23

    A wavefront curvature effect associated with a complex image produced by a synthetic aperture radar (SAR) can be mitigated based on which of a plurality of possible flight paths is taken by the SAR when capturing the image. The mitigation can be performed differently for different ones of the flight paths.

  9. Cockpit simulation study of use of flight path angle for instrument approaches

    NASA Technical Reports Server (NTRS)

    Hanisch, B.; Ernst, H.; Johnston, R.

    1981-01-01

    The results of a piloted simulation experiment to evaluate the effect of integrating flight path angle information into a typical transport electronic attitude director indicator display format for flight director instrument landing system approaches are presented. Three electronic display formats are evaluated during 3 deg straight-in approaches with wind shear and turbulence conditions. Flight path tracking data and pilot subjective comments are analyzed with regard to the pilot's tracking performance and workload for all three display formats.

  10. Spatial memory and stereotypy of flight paths by big brown bats in cluttered surroundings.

    PubMed

    Barchi, Jonathan R; Knowles, Jeffrey M; Simmons, James A

    2013-03-15

    The big brown bat, Eptesicus fuscus, uses echolocation for foraging and orientation. The limited operating range of biosonar implies that bats must rely upon spatial memory in familiar spaces with dimensions larger than a few meters. Prior experiments with bats flying in obstacle arrays have revealed differences in flight and acoustic emission patterns depending on the density and spatial extent of the obstacles. Using the same method, combined with acoustic microphone array tracking, we flew big brown bats in an obstacle array that varied in density and distribution in different locations in the flight room. In the initial experiment, six bats learned individually stereotyped flight patterns as they became familiar with the space. After the first day, the repetition rate of sonar broadcasts dropped to a stable level, consistent with low-density clutter. In a second experiment, after acquiring their stable paths, each bat was released from each of two unfamiliar locations in the room. Each bat still followed the same flight path it learned originally. In a third experiment, performed 1 month after the first two experiments, three of the bats were re-flown in the same configuration of obstacles; these three resumed flying in their accustomed path. The other three bats were flown in a mirror-image reconfiguration of the obstacles; these bats quickly found stable flight paths that differed from their originally learned paths. Overall, the flight patterns indicate that the bats perceive the cluttered space as a single scene through which they develop globally organized flight paths.

  11. Flight-path and airspeed control during landing approach for powered-lift aircraft

    NASA Technical Reports Server (NTRS)

    Franklin, J. A.; Innis, R. C.

    1974-01-01

    Manual control of flight path and airspeed during landing approach has been investigated for powered-lift transport aircraft. An analysis was conducted to identify the behavior of the aircraft which would be potentially significant to the pilot controlling flight path and airspeed during the approach. The response characteristics found to describe the aircraft behavior were (1) the initial flight-path response and flight-path overshoot for a step change in thrust, (2) the steady-state coupling of flight path and airspeed for a step change in thrust, and (3) the sensitivity of airspeed to changes in pitch attitude. The significance of these response characteristics was evaluated by pilots on a large-motion, ground-based simulator at Ames Research Center. Coupling between flight path and airspeed was considered by the pilot to be the dominant influence on handling qualities for the approach task. Results are compared with data obtained from flight tests of three existing powered-lift V/STOL aircraft.

  12. Functional integration of vertical flight path and speed control using energy principles

    NASA Technical Reports Server (NTRS)

    Lambregts, A. A.

    1984-01-01

    A generalized automatic flight control system was developed which integrates all longitudinal flight path and speed control functions previously provided by a pitch autopilot and autothrottle. In this design, a net thrust command is computed based on total energy demand arising from both flight path and speed targets. The elevator command is computed based on the energy distribution error between flight path and speed. The engine control is configured to produce the commanded net thrust. The design incorporates control strategies and hierarchy to deal systematically and effectively with all aircraft operational requirements, control nonlinearities, and performance limits. Consistent decoupled maneuver control is achieved for all modes and flight conditions without outer loop gain schedules, control law submodes, or control function duplication.

  13. Robust Flight Path Determination for Mars Precision Landing Using Genetic Algorithms

    NASA Technical Reports Server (NTRS)

    Bayard, David S.; Kohen, Hamid

    1997-01-01

    This paper documents the application of genetic algorithms (GAs) to the problem of robust flight path determination for Mars precision landing. The robust flight path problem is defined here as the determination of the flight path which delivers a low-lift open-loop controlled vehicle to its desired final landing location while minimizing the effect of perturbations due to uncertainty in the atmospheric model and entry conditions. The genetic algorithm was capable of finding solutions which reduced the landing error from 111 km RMS radial (open-loop optimal) to 43 km RMS radial (optimized with respect to perturbations) using 200 hours of computation on an Ultra-SPARC workstation. Further reduction in the landing error is possible by going to closed-loop control which can utilize the GA optimized paths as nominal trajectories for linearization.

  14. Improving the Flight Path Marker Symbol on Rotorcraft Synthetic Vision Displays

    NASA Technical Reports Server (NTRS)

    Szoboszlay, Zoltan P.; Hardy, Gordon H.; Welsh, Terence M.

    2004-01-01

    Two potential improvements to the flight path marker symbol were evaluated on a panel-mounted, synthetic vision, primary flight display in a rotorcraft simulation. One concept took advantage of the fact that synthetic vision systems have terrain height information available ahead of the aircraft. For this first concept, predicted altitude and ground track information was added to the flight path marker. In the second concept, multiple copies of the flight path marker were displayed at 3, 4, and 5 second prediction times as compared to a single prediction time of 3 seconds. Objective and subjective data were collected for eight rotorcraft pilots. The first concept produced significant improvements in pilot attitude control, ground track control, workload ratings, and preference ratings. The second concept did not produce significant differences in the objective or subjective measures.

  15. Aerodynamic investigations to determine possible ice flight paths

    NASA Technical Reports Server (NTRS)

    Burgsmueller, W.; Frenz, H.; May, P.; Anders, G.

    1982-01-01

    After flights with the VFW 614 under severe icing conditions, damage to the engine was found. In wind tunnel tests a determination of the origin of this ice was made; it is supposed that the damage was caused by this ice. On the modified flight test model of the VFW 614 on a 1:15 scale, measurements were conducted in the VFW-Fokker wind tunnel with exposed particles which represented the free ice. The results of this testing are presented.

  16. An evaluation of flight path formats head-up and head-down

    NASA Technical Reports Server (NTRS)

    Sexton, George A.; Moody, Laura E.; Evans, Joanne; Williams, Kenneth E.

    1988-01-01

    Flight path primary flight display formats were incorporated on head-up and head-down electronic displays and integrated into an Advanced Concepts Flight Simulator. Objective and subjective data were collected while ten airline pilots evaluated the formats by flying an approach and landing task under various ceiling, visibility and wind conditions. Deviations from referenced/commanded airspeed, horizontal track, vertical track and touchdown point were smaller using the head-up display (HUD) format than the head-down display (HDD) format, but not significantly smaller. Subjectively, the pilots overwhelmingly preferred (1) flight path formats over attitude formats used in current aircraft, and (2) the head-up presentation over the head-down, primarily because it eliminated the head-down to head-up transition during low visibility landing approaches. This report describes the simulator, the flight displays, the format evaluation, and the results of the objective and subjective data.

  17. Simulator evaluation of a flight-path-angle control system for a transport airplane with direct lift control

    NASA Technical Reports Server (NTRS)

    Kelley, W. W.

    1978-01-01

    A piloted simulator was used to evaluate the flight path angle control capabilities of a system that employs spoiler direct lift control. The system was designated the velocity vector control system and was compared with a baseline flight path angle control system which used elevator for control. The simulated airplane was a medium jet transport. Research pilots flew a manual instrument landing system glide slope tracking task and a variable flight path angle task in the landing configuration to obtain comparative performance data.

  18. Pilot usage of decoupled flight path and pitch controls

    NASA Technical Reports Server (NTRS)

    Berkhout, J.; Osgood, R.; Berry, D.

    1985-01-01

    Data from decoupled flight maneuvers have been collected and analyzed for four AFTI-F-16 pilots operating this aircraft's highly augmented fly-by-wire control system, in order to obtain spectral density, cross spectra, and Bode amplitude data, as well as coherences and phase angles for the two longitudinal axis control functions of each of 50 20-sec epochs. The analysis of each epoch yielded five distinct plotted parameters for the left hand twist grip and right hand sidestick controller output time series. These two control devices allow the left hand to generate vertical translation, direct lift, or pitch-pointing commands that are decoupled from those of the right hand. Attention is given to the control patterns obtained for decoupled normal flight, air-to-air gun engagement decoupled maneuvering, and decoupled air-to-surface bombing run maneuvering.

  19. NASA-FAA helicopter Microwave Landing System curved path flight test

    NASA Technical Reports Server (NTRS)

    Swenson, H. N.; Hamlin, J. R.; Wilson, G. W.

    1983-01-01

    An ongoing series of joint NASA/FAA helicopter Microwave Landing System (MLS) flight tests was conducted at Ames Research Center. This paper deals with tests done from the spring through the fall of 1983. This flight test investigated and developed solutions to the problem of manually flying curved-path and steep glide slope approaches into the terminal area using the MLS and flight director guidance. An MLS-equipped Bell UH-1H helicopter flown by NASA test pilots was used to develop approaches and procedures for flying these approaches. The approaches took the form of Straight-in, U-turn, and S-turn flightpaths with glide slopes of 6 deg, 9 deg, and 12 deg. These procedures were evaluated by 18 pilots from various elements of the helicopter community, flying a total of 221 hooded instrument approaches. Flying these curved path and steep glide slopes was found to be operationally acceptable with flight director guidance using the MLS.

  20. Determination of Flight Paths of an SBD-1 Airplane in Simulated Diving Attacks, Special Report

    NASA Technical Reports Server (NTRS)

    Johnson, Harold I.

    1943-01-01

    An investigation has been made to determine the motions of and the flight paths describe by a Navy dive-bombing airplane in simulated diving attacks. The data necessary to evaluate these items, with the exception of the atmospheric wind data, were obtained from automatic recording instruments installed entirely within the airplane. The atmospheric wind data were obtained from the ground by the balloon-theodolite method. The results of typical dives at various dive angles are presented in the form of time histories of the motion of the airplane as well as flight paths calculated with respect to still air and with respect to the ground.

  1. PRELIMINARY PROJECT PLAN FOR LANSCE INTEGRATED FLIGHT PATHS 11A, 11B, 12, and 13

    SciTech Connect

    D. H. BULTMAN; D. WEINACHT - AIRES CORP.

    2000-08-01

    This Preliminary Project Plan Summarizes the Technical, Cost, and Schedule baselines for an integrated approach to developing several flight paths at the Manual Lujan Jr. Neutron Scattering Center at the Los Alamos Neutron Science Center. For example, the cost estimate is intended to serve only as a rough order of magnitude assessment of the cost that might be incurred as the flight paths are developed. Further refinement of the requirements and interfaces for each beamline will permit additional refinement and confidence in the accuracy of all three baselines (Technical, Cost, Schedule).

  2. Mapping a Path to Autonomous Flight in the National Airspace

    NASA Technical Reports Server (NTRS)

    Lodding, Kenneth N.

    2011-01-01

    The introduction of autonomous flight, whether military, commercial, or civilian, into the National Airspace System (NAS) will present significant challenges. Minimizing the impact and preventing the changes from becoming disruptive, rather than an enhancing technology will not be without difficulty. From obstacle detection and avoidance to real-time verification and validation of system behavior, there are significant problems which must be solved prior to the general acceptance of autonomous systems. This paper examines some of the key challenges and the multi-disciplinary collaboration which must occur for autonomous systems to be accepted as equal partners in the NAS.

  3. A Flight-Path Control of Aircraft Based on Required Acceleration Vector

    NASA Astrophysics Data System (ADS)

    Yoshitani, Naoharu

    This paper presents an automatic flight-path control of aircraft. In the control, a desired flight trajectory is first determined as a sequence of straight lines, arcs and spirals in the three-dimensional space. Commands and command rates of heading and flight-path (climb) angles are then obtained from the desired trajectory. A required acceleration vector of the aircraft is calculated based on the command rates and angle deviations. Desired roll, pitch and yaw rates are then obtained by acceleration controller and are fed to attitude control. The feedback control of acceleration employs conventional PID control technology, without using inverse dynamics of the aircraft, and the attitude control can employ any existing control technologies suitable for the aircraft to be controlled. These make the proposed control relatively simple and easy to implement. Numerical simulations illustrate the effectiveness of the control.

  4. Behavioural mimicry in flight path of Batesian intraspecific polymorphic butterfly Papilio polytes.

    PubMed

    Kitamura, Tasuku; Imafuku, Michio

    2015-06-22

    Batesian mimics that show similar coloration to unpalatable models gain a fitness advantage of reduced predation. Beyond physical similarity, mimics often exhibit behaviour similar to their models, further enhancing their protection against predation by mimicking not only the model's physical appearance but also activity. In butterflies, there is a strong correlation between palatability and flight velocity, but there is only weak correlation between palatability and flight path. Little is known about how Batesian mimics fly. Here, we explored the flight behaviour of four butterfly species/morphs: unpalatable model Pachliopta aristolochiae, mimetic and non-mimetic females of female-limited mimic Papilio polytes, and palatable control Papilio xuthus. We demonstrated that the directional change (DC) generated by wingbeats and the standard deviation of directional change (SDDC) of mimetic females and their models were smaller than those of non-mimetic females and palatable controls. Furthermore, we found no significant difference in flight velocity among all species/morphs. By showing that DC and SDDC of mimetic females resemble those of models, we provide the first evidence for the existence of behavioural mimicry in flight path by a Batesian mimic butterfly.

  5. Behavioural mimicry in flight path of Batesian intraspecific polymorphic butterfly Papilio polytes

    PubMed Central

    Kitamura, Tasuku; Imafuku, Michio

    2015-01-01

    Batesian mimics that show similar coloration to unpalatable models gain a fitness advantage of reduced predation. Beyond physical similarity, mimics often exhibit behaviour similar to their models, further enhancing their protection against predation by mimicking not only the model's physical appearance but also activity. In butterflies, there is a strong correlation between palatability and flight velocity, but there is only weak correlation between palatability and flight path. Little is known about how Batesian mimics fly. Here, we explored the flight behaviour of four butterfly species/morphs: unpalatable model Pachliopta aristolochiae, mimetic and non-mimetic females of female-limited mimic Papilio polytes, and palatable control Papilio xuthus. We demonstrated that the directional change (DC) generated by wingbeats and the standard deviation of directional change (SDDC) of mimetic females and their models were smaller than those of non-mimetic females and palatable controls. Furthermore, we found no significant difference in flight velocity among all species/morphs. By showing that DC and SDDC of mimetic females resemble those of models, we provide the first evidence for the existence of behavioural mimicry in flight path by a Batesian mimic butterfly. PMID:26041360

  6. B-737 flight test of curved-path and steep-angle approaches using MLS guidance

    NASA Technical Reports Server (NTRS)

    Branstetter, J. R.; White, W. F.

    1989-01-01

    A series of flight tests were conducted to collect data for jet transport aircraft flying curved-path and steep-angle approaches using Microwave Landing System (MLS) guidance. During the test, 432 approaches comprising seven different curved-paths and four glidepath angles varying from 3 to 4 degrees were flown in NASA Langley's Boeing 737 aircraft (Transport Systems Research Vehicle) using an MLS ground station at the NASA Wallops Flight Facility. Subject pilots from Piedmont Airlines flew the approaches using conventional cockpit instrumentation (flight director and Horizontal Situation Indicator (HSI). The data collected will be used by FAA procedures specialists to develop standards and criteria for designing MLS terminal approach procedures (TERPS). The use of flight simulation techniques greatly aided the preliminary stages of approach development work and saved a significant amount of costly flight time. This report is intended to complement a data report to be issued by the FAA Office of Aviation Standards which will contain all detailed data analysis and statistics.

  7. A new chirp scaling algorithm of bistatic SAR with parallel flight paths

    NASA Astrophysics Data System (ADS)

    Li, Ning; Wang, Luping

    2011-10-01

    The precise point target reference spectrum of bistatic SAR has been a difficult problem for a long time. Many of the current available algorithms have approximation during deducing. This paper deduces the precise expression in Doppler- Frequency domain with the configuration of parallel flight paths and constant velocity of each platform. Then a new chirp scaling algorithm is put forward. At last, simulations are given to demonstrate the good focusing performance.

  8. From falling to flying: the path to powered flight of a robotic samara nano air vehicle.

    PubMed

    Ulrich, Evan R; Pines, Darryll J; Humbert, J Sean

    2010-12-01

    This paper details the development of a nano-scale (>15 cm) robotic samara, or winged seed. The design of prototypes inspired by naturally occurring geometries is presented along with a detailed experimental process which elucidates similarities between mechanical and robotic samara flight dynamics. The helical trajectories of a samara in flight were observed to differ in-flight path and descent velocity. The body roll and pitch angular rates for the differing trajectories were observed to be coupled to variations in wing pitch, and thus provide a means of control. Inspired by the flight modalities of the bio-inspired samaras, a robotic device has been created that mimics the autorotative capability of the samara, whilst providing the ability to hover, climb and translate. A high-speed camera-based motion capture system is used to observe the flight dynamics of the mechanical and robotic samara. Similarities in the flight dynamics are compared and discussed as it relates to the design of the robotic samara.

  9. Flight Path

    ERIC Educational Resources Information Center

    Ernst, Heidi

    2004-01-01

    Aviation High is a career and technical education school in the Long Island City neighborhood of Queens and the nation's largest aviation-focused high school. Required courses for all 2,000 students include the usual English, math, science, and foreign languages, but also airframe and power plant shops. A 5,000-square-foot annex at John F. Kennedy…

  10. Rotorcraft brownout mitigation through flight path optimization using a high fidelity rotorcraft simulation model

    NASA Astrophysics Data System (ADS)

    Alfred, Jillian Samantha

    Brownout conditions often occur during approach, landing, and take off in a desert environment and involve the entrainment and mobilization of loose sediment and dust into the rotor flow field. For this research, a high fidelity flight dynamics model is used to perform a study on brownout mitigation through operational means of flight path. In order for the high fidelity simulation to model an approach profile, a method for following specific profiles was developed. An optimization study was then performed using this flight dynamics model in a comprehensive brownout simulation. The optimization found a local shallow optimum approach and a global steep optimum approach minimized the intensity of the resulting brownout clouds. These results were consistent previous mitigation studies and operational methods. The results also demonstrated that the addition of a full rotorcraft model into the brownout simulation changed the characteristics of the velocity flow field, and hence changing the character of the brownout cloud that was produced.

  11. Altered orientation and flight paths of pigeons reared on gravity anomalies: a GPS tracking study.

    PubMed

    Blaser, Nicole; Guskov, Sergei I; Meskenaite, Virginia; Kanevskyi, Valerii A; Lipp, Hans-Peter

    2013-01-01

    The mechanisms of pigeon homing are still not understood, in particular how they determine their position at unfamiliar locations. The "gravity vector" theory holds that pigeons memorize the gravity vector at their home loft and deduct home direction and distance from the angular difference between memorized and actual gravity vector. However, the gravity vector is tilted by different densities in the earth crust leading to gravity anomalies. We predicted that pigeons reared on different gravity anomalies would show different initial orientation and also show changes in their flight path when crossing a gravity anomaly. We reared one group of pigeons in a strong gravity anomaly with a north-to-south gravity gradient, and the other group of pigeons in a normal area but on a spot with a strong local anomaly with a west-to-east gravity gradient. After training over shorter distances, pigeons were released from a gravitationally and geomagnetically normal site 50 km north in the same direction for both home lofts. As expected by the theory, the two groups of pigeons showed divergent initial orientation. In addition, some of the GPS-tracked pigeons also showed changes in their flight paths when crossing gravity anomalies. We conclude that even small local gravity anomalies at the birth place of pigeons may have the potential to bias the map sense of pigeons, while reactivity to gravity gradients during flight was variable and appeared to depend on individual navigational strategies and frequency of position updates.

  12. Vertical Field of View Reference Point Study for Flight Path Control and Hazard Avoidance

    NASA Technical Reports Server (NTRS)

    Comstock, J. Raymond, Jr.; Rudisill, Marianne; Kramer, Lynda J.; Busquets, Anthony M.

    2002-01-01

    Researchers within the eXternal Visibility System (XVS) element of the High-Speed Research (HSR) program developed and evaluated display concepts that will provide the flight crew of the proposed High-Speed Civil Transport (HSCT) with integrated imagery and symbology to permit path control and hazard avoidance functions while maintaining required situation awareness. The challenge of the XVS program is to develop concepts that would permit a no-nose-droop configuration of an HSCT and expanded low visibility HSCT operational capabilities. This study was one of a series of experiments exploring the 'design space' restrictions for physical placement of an XVS display. The primary experimental issues here was 'conformality' of the forward display vertical position with respect to the side window in simulated flight. 'Conformality' refers to the case such that the horizon and objects appear in the same relative positions when viewed through the forward windows or display and the side windows. This study quantified the effects of visual conformality on pilot flight path control and hazard avoidance performance. Here, conformality related to the positioning and relationship of the artificial horizon line and associated symbology presented on the forward display and the horizon and associated ground, horizon, and sky textures as they would appear in the real view through a window presented in the side window display. No significant performance consequences were found for the non-conformal conditions.

  13. Altered Orientation and Flight Paths of Pigeons Reared on Gravity Anomalies: A GPS Tracking Study

    PubMed Central

    Blaser, Nicole; Guskov, Sergei I.; Meskenaite, Virginia; Kanevskyi, Valerii A.; Lipp, Hans-Peter

    2013-01-01

    The mechanisms of pigeon homing are still not understood, in particular how they determine their position at unfamiliar locations. The “gravity vector” theory holds that pigeons memorize the gravity vector at their home loft and deduct home direction and distance from the angular difference between memorized and actual gravity vector. However, the gravity vector is tilted by different densities in the earth crust leading to gravity anomalies. We predicted that pigeons reared on different gravity anomalies would show different initial orientation and also show changes in their flight path when crossing a gravity anomaly. We reared one group of pigeons in a strong gravity anomaly with a north-to-south gravity gradient, and the other group of pigeons in a normal area but on a spot with a strong local anomaly with a west-to-east gravity gradient. After training over shorter distances, pigeons were released from a gravitationally and geomagnetically normal site 50 km north in the same direction for both home lofts. As expected by the theory, the two groups of pigeons showed divergent initial orientation. In addition, some of the GPS-tracked pigeons also showed changes in their flight paths when crossing gravity anomalies. We conclude that even small local gravity anomalies at the birth place of pigeons may have the potential to bias the map sense of pigeons, while reactivity to gravity gradients during flight was variable and appeared to depend on individual navigational strategies and frequency of position updates. PMID:24194860

  14. ''Latest Capabilities of Pov-Ray Ricochet Flight Path Analysis & Impact Probability Prediction Software''

    SciTech Connect

    Price, D.E.; Brereton, S.; Newton, M.; Moore, B.; Muirhead, D.; Pastrnak, J.; Prokosch, D.; Spence, B.; Towle, R.

    2000-09-05

    POV-Ray Ricochet Tracker is a freeware computer code developed to analyze high-speed fragment ricochet trajectory paths in complex 3-D areas such as explosives tiring chambers, facility equipment rooms, or shipboard Command and Control Centers. The code analyzes as many as millions of individual fragment trajectory paths in three dimensions and tracks these trajectory paths for up to four bounces through the three-dimensional model. It allows determination of the probabilities of hitting any designated areas or objects in the model. It creates renderings of any ricochet flight paths of interest in photo realistic renderings of the 3-D model. POV-Ray Ricochet Tracker is a customized version of the Persistence of Vision{trademark} Ray-Tracer (POV-Ray{trademark}) version 3.02 code for the Macintosh{trademark} Operating System (MacOS{trademark}). POV-Ray is a third generation graphics engine that creates three-dimensional, very high quality (photo-realistic) images with realistic reflections, shading, textures, perspective, and other effects using a rendering technique called ray-tracing. It reads a text tile that describes the objects, lighting, and camera location in a scene and generates an image of that scene from the viewpoint of the camera. More information about POV-Ray, including the executable and source code, may be found at http://www.povray.org. The customized code (POV-Ray Shrapnel Tracker, V3.02-Custom Build 2) generates individual fragment trajectory paths at any desired angle intervals in three dimensions. The code tracks these trajectory paths through any complex three-dimensional space, and outputs detailed data for each ray as requested by the user. The output may include trajectory source location, initial direction of each trajectory, vector data for each bounce point, and any impacts with designated model target surfaces during any trajectory segment (direct path or reflected paths). This allows determination of the three-dimensional trajectory of

  15. UAV-Based L-Band SAR with Precision Flight Path Control

    NASA Technical Reports Server (NTRS)

    Madsen, Soren N.; Hensley, Scott; Wheeler, Kevin; Sadowy, Greg; Miller, Tim; Muellerschoen, Ron; Lou, Yunling; Rosen, Paul

    2004-01-01

    NASA's Jet Propulsion Laboratory is currently implementing a reconfigurable polarimetric L-band synthetic aperture radar (SAR), specifically designed to acquire airborne repeat track interferometric (RTI) SAR data, also know as differential interferometric measurements. Differential interferometry can provide key displacement measurements, important for the scientific studies of Earthquakes and volcanoes. Using precision real-time GPS and a sensor controlled flight management system, the system will be able to fly predefined paths with great precision. The radar will be designed to operate on a UAV (Unmanned Arial Vehicle) but will initially be demonstrated on a minimally piloted vehicle (MPV), such as the Proteus build by Scaled Composites. The application requires control of the flight path to within a 10 meter tube to support repeat track and formation flying measurements. The design is fully polarimetric with an 80 MHz bandwidth (2 meter range resolution) and 16 kilometer range swath. The antenna is an electronically steered array to assure that the actual antenna pointing can be controlled independent of the wind direction and speed. The system will nominally operate at 45,000 ft. The program started out as a Instrument Incubator Project (IIP) funded by NASA Earth Science and Technology Office (ESTO).

  16. Responses of blowfly motion-sensitive neurons to reconstructed optic flow along outdoor flight paths.

    PubMed

    Boeddeker, N; Lindemann, J P; Egelhaaf, M; Zeil, J

    2005-12-01

    The retinal image flow a blowfly experiences in its daily life on the wing is determined by both the structure of the environment and the animal's own movements. To understand the design of visual processing mechanisms, there is thus a need to analyse the performance of neurons under natural operating conditions. To this end, we recorded flight paths of flies outdoors and reconstructed what they had seen, by moving a panoramic camera along exactly the same paths. The reconstructed image sequences were later replayed on a fast, panoramic flight simulator to identified, motion sensitive neurons of the so-called horizontal system (HS) in the lobula plate of the blowfly, which are assumed to extract self-motion parameters from optic flow. We show that under real life conditions HS-cells not only encode information about self-rotation, but are also sensitive to translational optic flow and, thus, indirectly signal information about the depth structure of the environment. These properties do not require an elaboration of the known model of these neurons, because the natural optic flow sequences generate--at least qualitatively--the same depth-related response properties when used as input to a computational HS-cell model and to real neurons.

  17. Strategies for Choosing Descent Flight-Path Angles for Small Jets

    NASA Technical Reports Server (NTRS)

    Wu, Minghong Gilbert; Green, Steven M.

    2012-01-01

    Three candidate strategies for choosing the descent flight path angle (FPA) for small jets are proposed, analyzed, and compared for fuel efficiency under arrival metering conditions. The strategies vary in operational complexity from a universally fixed FPA, or FPA function that varies with descent speed for improved fuel efficiency, to the minimum-fuel FPA computed for each flight based on winds, route, and speed profile. Methodologies for selecting the parameter for the first two strategies are described. The differences in fuel burn are analyzed over a year s worth of arrival traffic and atmospheric conditions recorded for the Dallas/Fort Worth (DFW) Airport during 2011. The results show that the universally fixed FPA strategy (same FPA for all flights, all year) burns on average 26 lbs more fuel per flight as compared to the minimum-fuel solution. This FPA is adapted to the arrival gate (direction of entry to the terminal) and various timespans (season, month and day) to improve fuel efficiency. Compared to a typical FPA of approximately 3 degrees the adapted FPAs vary significantly, up to 1.3 from one arrival gate to another or up to 1.4 from one day to another. Adapting the universally fixed FPA strategy to the arrival gate or to each day reduces the extra fuel burn relative to the minimum-fuel solution by 27% and 34%, respectively. The adaptations to gate and time combined shows up to 57% reduction of the extra fuel burn. The second strategy, an FPA function, contributes a 17% reduction in the 26 lbs of extra fuel burn over the universally fixed FPA strategy. Compared to the corresponding adaptations of the universally fixed FPA, adaptations of the FPA function reduce the extra fuel burn anywhere from 15-23% depending on the extent of adaptation. The combined effect of the FPA function strategy with both directional and temporal adaptation recovers 67% of the extra fuel relative to the minimum-fuel solution.

  18. Singular perturbation techniques for on-line optimal flight path control

    NASA Technical Reports Server (NTRS)

    Calise, A. J.

    1979-01-01

    This paper presents a partial evaluation on the use of singular perturbation methods for developing computer algorithms for on-line optimal control of aircraft. The evaluation is based on a study of the minimum time intercept problem using F-4 aerodynamic and propulsion data as a base line. The extensions over previous work on this subject are that aircraft turning dynamics (in addition to position and energy dynamics) are included in the analysis, the algorithm is developed for a moving end point and is adaptive to unpredictable target maneuvers, and short range maneuvers that do not have a cruise leg are included. Particular attention is given to identifying those quantities that can be precomputed and stored (as a function of aircraft total energy), thus greatly reducing the onboard computational load. Numerical results are given that illustrate the nature of the optimal intercept flight paths, and an estimate is given for the execution time and storage requirements of the control algorithm.

  19. A Heading and Flight-Path Angle Control of Aircraft Based on Required Acceleration Vector

    NASA Astrophysics Data System (ADS)

    Yoshitani, Naoharu

    This paper describes a control of heading and flight-path angles of aircraft to time-varying command angles. The controller first calculates an acceleration command vector (acV), which is vertical to the velocity vector. acV consists of two components; the one is feedforward acceleration obtained from the rates of command angles, and the other is feedback acceleration obtained from angle deviations by using PID control law. A bank angle command around the velocity vector and commands of pitch and yaw rates are then obtained to generate the required acceleration. A roll rate command is calculated from bank angle deviation. Roll, pitch and yaw rate commands are put into the attitude controller, which can be composed of any suitable control laws such as PID control. The control requires neither aerodynamic coefficients nor online calculation of the inverse dynamics of the aircraft. A numerical simulation illustrates the effects of the control.

  20. Flight path control strategies and preliminary deltaV requirements for the 2007 Mars Phoenix (PHX) mission

    NASA Technical Reports Server (NTRS)

    Raofi, Behzad

    2005-01-01

    This paper describes the methods used to estimate the statistical deltaV requirements for the propulsive maneuvers that will deliver the spacecraft to its target landing site while satisfying planetary protection requirements. the paper presents flight path control analysis results for three different trajectories, open, middle, and close of launch period for the mission.

  1. Effects of Inboard Horizontal Field of View Display Limitations on Pilot Path Control During Total In-Flight Simulator (TIFS) Flight Test

    NASA Technical Reports Server (NTRS)

    Kramer, Lynda J.; Parrish, Russell V.; Williams, Steven P.; Lavell, Jeffrey S.

    1999-01-01

    A flight test was conducted aboard Calspan's Total In-Flight Simulator (TIFS) aircraft by researchers within the External Visibility System (XVS) element of the High-Speed Research program. The purpose was to investigate the effects of inboard horizontal field of view (FOV) display limitations on pilot path control and to learn about the TIFS capabilities and limitations for possible use in future XVS flight tests. The TIFS cockpit windows were masked to represent the front XVS display area and the High-Speed Civil Transport side windows, as viewed by the pilot. Masking limited the forward FOV to 40 deg. horizontal and 50 deg. vertical for the basic flight condition, With an increase of 10 deg. horizontal in the inboard direction for the increased FOV flight condition. Two right-hand approach tasks (base-downwind-final) with a left crosswind on final were performed by three pilots using visual flight rules at Niagara Falls Airport. Each of the two tasks had three replicates for both horizontal FOV conditions, resulting in twelve approaches per test subject. Limited objective data showed that an increase of inboard FOV had no effect (deficiences in objective data measurement capabilities were noted). However, subjective results showed that a 50 deg. FOV was preferred over the 40 deg. FOV.

  2. Empirical determination of solar proton access to the atmosphere: Impact on polar flight paths

    NASA Astrophysics Data System (ADS)

    Neal, Jason J.; Rodger, Craig J.; Green, Janet C.

    2013-07-01

    Violent expulsions on the Sun's surface release high energy solar protons that ultimately affect HF communication used by aircraft. The geomagnetic field screens the low altitude equatorial region, but these protons can access the atmosphere over the poles. The latitudes over which the solar protons can reach vary with geomagnetic indices such as Kp and Dst. In this study we use observations from low Earth orbit to determine the atmospheric access of solar protons and hence the flights paths most likely to be affected. Observations taken by up to six polar orbiting satellites during 15 solar proton events are analyzed. From this we determine 16,850 proton rigidity cutoff estimates across three energy channels. Empirical fits are undertaken to estimate the most likely behavior of the cutoff dependence with geomagnetic activity. The changing Kp value is found to lead the variation in the cutoffs by ~3 h. We provide simple equations by which the geomagnetic latitude at which the protons impact the atmosphere can be determined from a given Kp or Dst value. The variation found in the cutoff with Kp is similar to that used in existing operational models, although we suggest that a ~1-2° equatorward shift in latitude would provide greater accuracy. We find that a Kp predictive model can provide additional warning to the variation in proton cutoffs. Hence, a prediction of the cutoff latitudes can be made ~3 h to as much as 7 h into the future, meeting suggested minimum planning times required by the aviation industry.

  3. An adaptive dual-optimal path-planning technique for unmanned air vehicles with application to solar-regenerative high altitude long endurance flight

    NASA Astrophysics Data System (ADS)

    Whitfield, Clifford A.

    2009-12-01

    A multi-objective technique for Unmanned Air Vehicle (UAV) path and trajectory autonomy generation, through task allocation and sensor fusion has been developed. The Dual-Optimal Path-Planning (D-O.P-P.) Technique generates on-line adaptive flight paths for UAVs based on available flight windows and environmental influenced objectives. The environmental influenced optimal condition, known as the driver' determines the condition, within a downstream virtual window of possible vehicle destinations and orientation built from the UAV kinematics. The intermittent results are pursued by a dynamic optimization technique to determine the flight path. This sequential optimization technique is a multi-objective optimization procedure consisting of two goals, without requiring additional information to combine the conflicting objectives into a single-objective. An example case-study and additional applications are developed and the results are discussed; including the application to the field of Solar Regenerative (SR) High Altitude Long Endurance (HALE) UAV flight. Harnessing solar energy has recently been adapted for use on high altitude UAV platforms. An aircraft that uses solar panels and powered by the sun during the day and through the night by SR systems, in principle could sustain flight for weeks or months. The requirements and limitations of solar powered flight were determined. The SR-HALE UAV platform geometry and flight characteristics were selected from an existing aircraft that has demonstrated the capability for sustained flight through flight tests. The goals were to maintain continual Situational Awareness (SA) over a case-study selected Area of Interest (AOI) and existing UAV power and surveillance systems. This was done for still wind and constant wind conditions at altitude along with variations in latitude. The characteristics of solar flux and the dependence on the surface location and orientation were established along with fixed flight maneuvers for

  4. A Flight Dynamic Simulation Program in Air-Path Axes Using ACSL (Advanced Continuous Simulation Language).

    DTIC Science & Technology

    1986-06-01

    NO-A±?3 649 A FLIGHT DYNANIC SINULRTION PROGRAM IN AIR-PRTH AXES 11𔃼 USING ACSL (ADVANCED.. (U) AERONAUTICAL RESEARCH LABS MELBOURNE (AUSTRALIA) P W...Aeronajutical Restvarch Laboratrmes, ....,. i P.O. Box 4331,M lo re Vic:toria. 3001, Aus trali ."-" Melbourne.-a ’ 𔃾’ -- .-,, : _" • , (C) CMMONWALTH F...of time dependent results . e Tne DERIVATIVE section contains tne aitnd1- of the six degrees look- of freedom flight model. Tr imm inrg o f tnte a ir

  5. Aircraft automatic-flight-control system with inversion of the model in the feed-forward path using a Newton-Raphson technique for the inversion

    NASA Technical Reports Server (NTRS)

    Smith, G. A.; Meyer, G.; Nordstrom, M.

    1986-01-01

    A new automatic flight control system concept suitable for aircraft with highly nonlinear aerodynamic and propulsion characteristics and which must operate over a wide flight envelope was investigated. This exact model follower inverts a complete nonlinear model of the aircraft as part of the feed-forward path. The inversion is accomplished by a Newton-Raphson trim of the model at each digital computer cycle time of 0.05 seconds. The combination of the inverse model and the actual aircraft in the feed-forward path alloys the translational and rotational regulators in the feedback path to be easily designed by linear methods. An explanation of the model inversion procedure is presented. An extensive set of simulation data for essentially the full flight envelope for a vertical attitude takeoff and landing aircraft (VATOL) is presented. These data demonstrate the successful, smooth, and precise control that can be achieved with this concept. The trajectory includes conventional flight from 200 to 900 ft/sec with path accelerations and decelerations, altitude changes of over 6000 ft and 2g and 3g turns. Vertical attitude maneuvering as a tail sitter along all axes is demonstrated. A transition trajectory from 200 ft/sec in conventional flight to stationary hover in the vertical attitude includes satisfactory operation through lift-cure slope reversal as attitude goes from horizontal to vertical at constant altitude. A vertical attitude takeoff from stationary hover to conventional flight is also demonstrated.

  6. Flight paths of seabirds soaring over the ocean surface enable measurement of fine-scale wind speed and direction.

    PubMed

    Yonehara, Yoshinari; Goto, Yusuke; Yoda, Ken; Watanuki, Yutaka; Young, Lindsay C; Weimerskirch, Henri; Bost, Charles-André; Sato, Katsufumi

    2016-08-09

    Ocean surface winds are an essential factor in understanding the physical interactions between the atmosphere and the ocean. Surface winds measured by satellite scatterometers and buoys cover most of the global ocean; however, there are still spatial and temporal gaps and finer-scale variations of wind that may be overlooked, particularly in coastal areas. Here, we show that flight paths of soaring seabirds can be used to estimate fine-scale (every 5 min, ∼5 km) ocean surface winds. Fine-scale global positioning system (GPS) positional data revealed that soaring seabirds flew tortuously and ground speed fluctuated presumably due to tail winds and head winds. Taking advantage of the ground speed difference in relation to flight direction, we reliably estimated wind speed and direction experienced by the birds. These bird-based wind velocities were significantly correlated with wind velocities estimated by satellite-borne scatterometers. Furthermore, extensive travel distances and flight duration of the seabirds enabled a wide range of high-resolution wind observations, especially in coastal areas. Our study suggests that seabirds provide a platform from which to measure ocean surface winds, potentially complementing conventional wind measurements by covering spatial and temporal measurement gaps.

  7. Flight paths of seabirds soaring over the ocean surface enable measurement of fine-scale wind speed and direction

    PubMed Central

    Yonehara, Yoshinari; Goto, Yusuke; Yoda, Ken; Watanuki, Yutaka; Young, Lindsay C.; Weimerskirch, Henri; Bost, Charles-André; Sato, Katsufumi

    2016-01-01

    Ocean surface winds are an essential factor in understanding the physical interactions between the atmosphere and the ocean. Surface winds measured by satellite scatterometers and buoys cover most of the global ocean; however, there are still spatial and temporal gaps and finer-scale variations of wind that may be overlooked, particularly in coastal areas. Here, we show that flight paths of soaring seabirds can be used to estimate fine-scale (every 5 min, ∼5 km) ocean surface winds. Fine-scale global positioning system (GPS) positional data revealed that soaring seabirds flew tortuously and ground speed fluctuated presumably due to tail winds and head winds. Taking advantage of the ground speed difference in relation to flight direction, we reliably estimated wind speed and direction experienced by the birds. These bird-based wind velocities were significantly correlated with wind velocities estimated by satellite-borne scatterometers. Furthermore, extensive travel distances and flight duration of the seabirds enabled a wide range of high-resolution wind observations, especially in coastal areas. Our study suggests that seabirds provide a platform from which to measure ocean surface winds, potentially complementing conventional wind measurements by covering spatial and temporal measurement gaps. PMID:27457932

  8. Sensing and reconstruction of arbitrary light-in-flight paths by a relativistic imaging approach

    NASA Astrophysics Data System (ADS)

    Laurenzis, Martin; Klein, Jonathan; Bacher, Emmanuel; Metzger, Nicolas; Christnacher, Frank

    2016-10-01

    Transient light imaging is an emerging technology and interesting sensing approach for fundamental multidisciplinary research ranging from computer science to remote sensing. Recent developments in sensor technologies and computational imaging has made this emerging sensing approach a candidate for next generation sensor systems with rapidly increasing maturity but still relay on laboratory technology demonstrations. At ISL, transient light sensing is investigated by time correlated single photon counting (TCSPC). An eye-safe shortwave infrared (SWIR) TCSPC setup, consisting of an avalanche photodiode array and a pulsed fiber laser source, is used to investigate sparsely scattered light while propagating through air. Fundamental investigation of light in light are carried out with the aim to reconstruct the propagation path of arbitrary light paths. Light pulses are observed in light at various propagation angles and distances. As demonstrated, arbitrary light paths can be distinguished due to a relativistic effect leading to a distortion of temporal signatures. A novel method analyzing the time difference of arrival (TDOA) is carried out to determine the propagation angle and distance with respect to this relativistic effect. Based on our results, the performance of future laser warning receivers can be improved by the use of single photon counting imaging devices. They can detect laser light even when the laser does not directly hit the sensor or is passing at a certain distance.

  9. Evaluation of unmanned aerial vehicle shape, flight path and camera type for waterfowl surveys: disturbance effects and species recognition

    PubMed Central

    Hall, Graham P.; McDonald, Paul G.

    2016-01-01

    The use of unmanned aerial vehicles (UAVs) for ecological research has grown rapidly in recent years, but few studies have assessed the disturbance impacts of these tools on focal subjects, particularly when observing easily disturbed species such as waterfowl. In this study we assessed the level of disturbance that a range of UAV shapes and sizes had on free-living, non-breeding waterfowl surveyed in two sites in eastern Australia between March and May 2015, as well as the capability of airborne digital imaging systems to provide adequate resolution for unambiguous species identification of these taxa. We found little or no obvious disturbance effects on wild, mixed-species flocks of waterfowl when UAVs were flown at least 60m above the water level (fixed wing models) or 40m above individuals (multirotor models). Disturbance in the form of swimming away from the UAV through to leaving the water surface and flying away from the UAV was visible at lower altitudes and when fixed-wing UAVs either approached subjects directly or rapidly changed altitude and/or direction near animals. Using tangential approach flight paths that did not cause disturbance, commercially available onboard optical equipment was able to capture images of sufficient quality to identify waterfowl and even much smaller taxa such as swallows. Our results show that with proper planning of take-off and landing sites, flight paths and careful UAV model selection, UAVs can provide an excellent tool for accurately surveying wild waterfowl populations and provide archival data with fewer logistical issues than traditional methods such as manned aerial surveys. PMID:27020132

  10. Evaluation of unmanned aerial vehicle shape, flight path and camera type for waterfowl surveys: disturbance effects and species recognition.

    PubMed

    McEvoy, John F; Hall, Graham P; McDonald, Paul G

    2016-01-01

    The use of unmanned aerial vehicles (UAVs) for ecological research has grown rapidly in recent years, but few studies have assessed the disturbance impacts of these tools on focal subjects, particularly when observing easily disturbed species such as waterfowl. In this study we assessed the level of disturbance that a range of UAV shapes and sizes had on free-living, non-breeding waterfowl surveyed in two sites in eastern Australia between March and May 2015, as well as the capability of airborne digital imaging systems to provide adequate resolution for unambiguous species identification of these taxa. We found little or no obvious disturbance effects on wild, mixed-species flocks of waterfowl when UAVs were flown at least 60m above the water level (fixed wing models) or 40m above individuals (multirotor models). Disturbance in the form of swimming away from the UAV through to leaving the water surface and flying away from the UAV was visible at lower altitudes and when fixed-wing UAVs either approached subjects directly or rapidly changed altitude and/or direction near animals. Using tangential approach flight paths that did not cause disturbance, commercially available onboard optical equipment was able to capture images of sufficient quality to identify waterfowl and even much smaller taxa such as swallows. Our results show that with proper planning of take-off and landing sites, flight paths and careful UAV model selection, UAVs can provide an excellent tool for accurately surveying wild waterfowl populations and provide archival data with fewer logistical issues than traditional methods such as manned aerial surveys.

  11. Lévy flights in confining environments: Random paths and their statistics

    NASA Astrophysics Data System (ADS)

    Żaba, Mariusz; Garbaczewski, Piotr; Stephanovich, Vladimir

    2013-09-01

    We analyze a specific class of random systems that, while being driven by a symmetric Lévy stable noise, asymptotically set down at the Boltzmann-type equilibrium, represented by a probability density function (pdf) ρ∗(x)˜exp[-Φ(x)]. This behavior needs to be contrasted with the standard Langevin representation of Lévy jump-type processes. It is known that the choice of the drift function in the Newtonian form ˜-∇Φ excludes the existence of the Boltzmannian pdf ˜exp[-Φ(x)] (Eliazar-Klafter no go theorem). In view of this incompatibility statement, our main goal here is to establish the appropriate path-wise description of the equilibrating jump-type process. A priori given inputs are (i) jump transition rates entering the master equation for ρ(x,t) and (ii) the target (invariant) pdf ρ∗(x) of that equation, in the Boltzmannian form. We resort to numerical methods and construct a suitable modification of the Gillespie algorithm, originally invented in the chemical kinetics context. The generated sample trajectories show up a qualitative typicality, e.g. they display structural features of jumping paths (predominance of small vs large jumps) specific to particular stability indices μ∈(0,2). The obtained random paths statistical data allow us to infer an associated pdf ρ(x,t) dynamics which stands for a validity check of our procedure. The considered exemplary Boltzmannian equilibria ˜exp[-Φ(x)] refer to (i) harmonic potential Φ˜x2, (ii) logarithmic potential Φ˜nln(1+x2) with n=1,2 and (iii) locally periodic confining potential Φ˜sin2(2πx),|x|≤2, Φ˜(x2-4),|x|>2.

  12. Evaluation of a computer-generated perspective tunnel display for flight path following

    NASA Technical Reports Server (NTRS)

    Grunwald, A. J.; Robertson, J. B.; Hatfield, J. J.

    1980-01-01

    The display was evaluated by monitoring pilot performance in a fixed base simulator with the vehicle dynamics of a CH-47 tandem rotor helicopter. Superposition of the predicted future vehicle position on the tunnel image was also investigated to determine whether, and to what extent, it contributes to better system performance (the best predicted future vehicle position was sought). Three types of simulator experiments were conducted: following a desired trajectory in the presence of disturbances; entering the trajectory from a random position, outside the trajectory; detecting and correcting failures in automatic flight. The tunnel display with superimposed predictor/director symbols was shown to be a very successful combination, which outperformed the other two displays in all three experiments. A prediction time of 4 to 7 sec. was found to optimize trajectory tracking for the given vehicle dynamics and flight condition. Pilot acceptance of the tunnel plus predictor/director display was found to be favorable and the time the pilot needed for familiarization with the display was found to be relatively short.

  13. Volume-imaging lidar observations of the convective structure surrounding the flight path of a flux-measuring aircraft

    NASA Technical Reports Server (NTRS)

    Eloranta, Edwin W.; Forrest, Daniel K.

    1992-01-01

    The University of Wisconsin volume imaging lidar has been used to portray images of the three-dimensional structure of clear air convective plumes in the atmosphere surrounding the flight path of the instrumented Twin Otter aircraft operated by the National Aeronautical Establishment of Canada. Lidar images provide a context for interpretation of the aircraft measurements. The position of data points within a convective element can be determined and the temporal development of the plume can be observed to time the observation with respect to the life cycle of the plume. Plots of the vertical flux of water vapor, superimposed on lidar images clearly demonstrate the well-known sampling difficulties encountered when attempting to measure fluxes near the top of the convective layer. When loran was used to determine average aircraft velocity, flight-leg-averaged horizontal winds measured by the aircraft and area-averaged winds measured by lidar agree to within 0.2 m/s in speed and 1 deg in direction.

  14. Volume-imaging lidar observations of the convective structure surrounding the flight path of a flux-measuring aircraft

    NASA Astrophysics Data System (ADS)

    Eloranta, Edwin W.; Forrest, Daniel K.

    1992-11-01

    The University of Wisconsin volume imaging lidar has been used to portray images of the three-dimensional structure of clear air convective plumes in the atmosphere surrounding the flight path of the instrumented Twin Otter aircraft operated by the National Aeronautical Establishment (NAE) of Canada. Lidar images provide a context for interpretation of the aircraft measurements. The position of data points within a convective element can be determined and the temporal development of the plume can be observed to time the observation with respect to the life cycle of the plume. Plots of the vertical flux of water vapor, q'w', superimposed on lidar images clearly demonstrate the well-known sampling difficulties encountered when attempting to measure fluxes near the top of the convective layer. When Loran was used to determine average aircraft velocity, flight-leg-averaged horizontal winds measured by the aircraft and area-averaged winds measured by lidar agree to within 0.2 m s-1 in speed and 1° in direction.

  15. An evaluation of flight path management automation in transport category aircraft

    NASA Technical Reports Server (NTRS)

    Chandra, D.; Bussolari, S. R.

    1991-01-01

    A desk-top simulation of a Boeing 757/767 Electronic Flight Instrumentation System (EFIS) and Control Display Unit (CDU) was used in an experiment to compare three modes of communication for the clearance amendment process: standard voice procedures, a textual delivery method, and a graphical delivery method. Eight qualified Boeing 757/767 pilots served as subjects. Each flew nine landing scenarios with three amendments given in each scenario. Both acceptable and unacceptable clearance amendments were presented in order to assess situational awareness. Times for comprehension and execution of the amendment were recorded along with workload ratings, responses to unacceptable amendments, and subjective impressions. The graphical mode was found to be superior in terms of the time measures and subjective ratings. No difference was found between the modes in the ability to detect unacceptable clearances.

  16. Conformal flight path symbology for head-up displays: Defining the distribution of visual attention in three-dimensional space

    NASA Astrophysics Data System (ADS)

    Ververs, Patricia May

    An extensive investigation of the format for head-up display (HUD) instrumentation was conducted in a two-part experiment. First, a pilot's information requirements for the tasks of approach, landing, and taxi were determined through a survey administered to professional commercial pilots via the world wide web. The results of the survey were applied in the development of two symbology sets, one set for flight navigation and the second for ground navigation. Second, twenty pilots from the University of Illinois at Urbana-Champaign were recruited to participate in a 3-day experiment. The study was designed to investigate the format for symbology on HUDs and the performance effects of using conformal and partially conformal symbology to support the pilots' tasks. In addition, two different methods were investigated for supporting the pilots' transition between the task of flying and the task of landing. A seamless transition used visual momentum techniques to smoothly guide the pilots' cognitive transition between the serial displays and the associated tasks. A seamed approach employed an abrupt change between the displays to alert the pilots of the task switch. The results indicate that incorporating a virtually conformal, tunnel-in-the-sky symbology into a complete HUD instrumentation set offers promising pilot performance effects. Pilots easily navigated the complex curved approaches with little to no deviation from the flight path (approximately 10 feet), while performing the secondary tasks of the scanning their instruments and the environment. The seamless transition between the flight and ground symbology offered the pilots a preview of the upcoming landing task, thereby preparing them for the task switch. On the ground, the perspective (scene-linked) symbology set supported landing and taxi navigation tasks with the equal efficiency to the plan view display but with much greater precision. Theories of allocation of attention were used to interpret the

  17. Flight tests of three-dimensional path-redefinition algorithms for transition from Radio Navigation (RNAV) to Microwave Landing System (MLS) navigation when flying an aircraft on autopilot

    NASA Technical Reports Server (NTRS)

    Hueschen, Richard M.

    1988-01-01

    This report contains results of flight tests for three path update algorithms designed to provide smooth transition for an aircraft guidance system from DME, VORTAC, and barometric navaids to the more precise MLS by modifying the desired 3-D flight path. The first algorithm, called Zero Cross Track, eliminates the discontinuity in cross-track and altitude error at transition by designating the first valid MLS aircraft position as the desired first waypoint, while retaining all subsequent waypoints. The discontinuity in track angle is left unaltered. The second, called Tangent Path, also eliminates the discontinuity in cross-track and altitude errors and chooses a new desired heading to be tangent to the next oncoming circular arc turn. The third, called Continued Track, eliminates the discontinuity in cross-track, altitude, and track angle errors by accepting the current MLS position and track angle as the desired ones and recomputes the location of the next waypoint. The flight tests were conducted on the Transportation Systems Research Vehicle, a small twin-jet transport aircraft modified for research under the Advanced Transport Operating Systems program at Langley Research Center. The flight tests showed that the algorithms provided a smooth transition to MLS.

  18. Path-integral formulation for Lévy flights: Evaluation of the propagator for free, linear, and harmonic potentials in the over- and underdamped limits

    NASA Astrophysics Data System (ADS)

    Janakiraman, Deepika; Sebastian, K. L.

    2012-12-01

    Lévy flights can be described using a Fokker-Planck equation, which involves a fractional derivative operator in the position coordinate. Such an operator has its natural expression in the Fourier domain. Starting with this, we show that the solution of the equation can be written as a Hamiltonian path integral. Though this has been realized in the literature, the method has not found applications as the path integral appears difficult to evaluate. We show that a method in which one integrates over the position coordinates first, after which integration is performed over the momentum coordinates, can be used to evaluate several path integrals that are of interest. Using this, we evaluate the propagators for (a) free particle, (b) particle subjected to a linear potential, and (c) harmonic potential. In all the three cases, we have obtained results for both overdamped and underdamped cases.

  19. Comparative Flow Path Analysis and Design Assessment of an Axisymmetric Hydrogen Fueled Scramjet Flight Test Engine at a Mach Number of 6.5

    NASA Technical Reports Server (NTRS)

    McClinton, C.; Rondakov, A.; Semenov, V.; Kopehenov, V.

    1991-01-01

    NASA has contracted with the Central Institute of Aviation Motors CIAM to perform a flight test and ground test and provide a scramjet engine for ground test in the United States. The objective of this contract is to obtain ground to flight correlation for a supersonic combustion ramjet (scramjet) engine operating point at a Mach number of 6.5. This paper presents results from a flow path performance and thermal evaluation performed on the design proposed by the CIAM. This study shows that the engine will perform in the scramjet mode for stoichiometric operation at a flight Mach number of 6.5. Thermal assessment of the structure indicates that the combustor cooling liner will provide adequate cooling for a Mach number of 6.5 test condition and that optional material proposed by CIAM for the cowl leading-edge design are required to allow operation with or without a type IV shock-shock interaction.

  20. Motion of a ballistic missile angularly misaligned with the flight path upon entering the atmosphere and its effect upon aerodynamic heating, aerodynamic loads, and miss distance

    NASA Technical Reports Server (NTRS)

    Allen, Julian H

    1957-01-01

    An analysis is given of the oscillating motion of a ballistic missile which upon entering the atmosphere is angularly misaligned with respect to the flight path. The history of the motion for some example missiles is discussed from the point of view of the effect of the motion on the aerodynamic heating and loading. The miss distance at the target due to misalignment and to small accidental trim angles is treated. The stability problem is also discussed for the case where the missile is tumbling prior to atmospheric entry.

  1. The Human Space Life Sciences Critical Path Roadmap Project: A Strategy for Human Space Flight through Exploration-Class Missions

    NASA Technical Reports Server (NTRS)

    Sawin, Charles F.

    1999-01-01

    The product of the critical path roadmap project is an integrated strategy for mitigating the risks associated with human exploration class missions. It is an evolving process that will assure the ability to communicate the integrated critical path roadmap. Unlike previous reports, this one will not sit on a shelf - it has the full support of the JSC Space and Life Sciences Directorate (SA) and is already being used as a decision making tool (e.g., budget and investigation planning for Shuttle and Space Station mission). Utility of this product depends on many efforts, namely: providing the required information (completed risk data sheets, critical question information, technology data). It is essential to communicate the results of the critical path roadmap to the scientific community - this meeting is a good opportunity to do so. The web site envisioned for the critical path roadmap will provide the capability to communicate to a broader community and to track and update the system routinely.

  2. Characteristics of wake vortex generated by a Boeing 727 jet transport during two-segment and normal ILS approach flight paths

    NASA Technical Reports Server (NTRS)

    Kurkowski, R. L.; Barber, M. R.; Garodz, L. J.

    1976-01-01

    A series of flight tests was conducted to evaluate the vortex wake characteristics of a Boeing 727 (B727-200) aircraft during conventional and two-segment ILS approaches. Twelve flights of the B727, which was equipped with smoke generators for vortex marking, were flown and its vortex wake was intentionally encountered by a Lear Jet model 23 (LR-23) and a Piper Twin Comanche (PA-30). Location of the B727 vortex during landing approach was measured using a system of photo-theodolites. The tests showed that at a given separation distance there were no readily apparent differences in the upsets resulting from deliberate vortex encounters during the two types of approaches. Timed mappings of the position of the landing configuration vortices showed that they tended to descend approximately 91 m(300 ft) below the flight path of the B727. The flaps of the B727 have a dominant effect on the character of the trailed wake vortex. The clean wing produces a strong, concentrated vortex but as the flaps are lowered, the vortex system becomes more diffuse. Pilot opinion and roll acceleration data indicate that 4.5 n.mi. would be a minimum separation distance at which roll control of light aircraft (less than 5,670 kg (12,500 lb) could be maintained during parallel encounters of the B727's landing configuration wake. This minimum separation distance is generally in scale with results determined from previous tests of other aircraft using the small roll control criteria.

  3. Goldstein-Kac telegraph processes with random speeds: Path probabilities, likelihoods, and reported Lévy flights

    NASA Astrophysics Data System (ADS)

    Sim, Aaron; Liepe, Juliane; Stumpf, Michael P. H.

    2015-04-01

    The Goldstein-Kac telegraph process describes the one-dimensional motion of particles with constant speed undergoing random changes in direction. Despite its resemblance to numerous real-world phenomena, the singular nature of the resultant spatial distribution of each particle precludes the possibility of any a posteriori empirical validation of this random-walk model from data. Here we show that by simply allowing for random speeds, the ballistic terms are regularized and that the diffusion component can be well-approximated via the unscented transform. The result is a computationally efficient yet robust evaluation of the full particle path probabilities and, hence, the parameter likelihoods of this generalized telegraph process. We demonstrate how a population diffusing under such a model can lead to non-Gaussian asymptotic spatial distributions, thereby mimicking the behavior of an ensemble of Lévy walkers.

  4. New Results from Frequency and Energy Reference Measurements during the first Test Flight with the Airborne Integrated Path Differential Absorption Lidar System CHARM-F

    NASA Astrophysics Data System (ADS)

    Ehret, G.; Fix, A.; Amediek, A.; Quatrevalet, M.

    2015-12-01

    The Integrated Path Differential Absorption Lidar (IPDA) technique is regarded as a suitable means for the measurement of methane and carbon dioxide columns from satellite or aircraft platforms with unprecedented accuracy. Currently, the German-French methane mission MERLIN (Methan Remote Lidar Mission) is prepared. At the same time CHARM-F, an aircraft installed system has been developed at DLR as an airborne demonstrator for a spaceborne greenhouse gas mission. Both use e.g. optical parametric oscillators (OPOs) in a double-pulse mode as the transmitter. Of particular importance for both instruments are the sub-modules required for the frequency stabilization of the transmitter wavelength and, since the IPDA technique, in contrast to DIAL, requires the exact knowledge of the energy ratio of outgoing on-line. The coherence of the lidar transmitter gives rise to speckle effects which have to be considered for the monitoring of the energy ratio of outgoing on- and off-line pulses. For the frequency reference of CHARM-F, a very successful stabilization scheme has been developed which will also serve as the reference for MERLIN. In Spring 2015, CHARM-F was flown aboard the German HALO aircraft for the first time which enables a detailed view on the performance of both the energy calibration and frequency reference subsystems under real flight conditions. As an initial quality check we will compared the airborne results to previous lab measurements which have been performed under stable environmental conditions.

  5. Path Finder

    SciTech Connect

    Rigdon, J. Brian; Smith, Marcus Daniel; Mulder, Samuel A

    2014-01-07

    PathFinder is a graph search program, traversing a directed cyclic graph to find pathways between labeled nodes. Searches for paths through ordered sequences of labels are termed signatures. Determining the presence of signatures within one or more graphs is the primary function of Path Finder. Path Finder can work in either batch mode or interactively with an analyst. Results are limited to Path Finder whether or not a given signature is present in the graph(s).

  6. Kinetographic determination of airplane flight characteristics

    NASA Technical Reports Server (NTRS)

    Raethjen, P; Knott, H

    1927-01-01

    The author's first experiments with a glider on flight characteristics demonstrated that an accurate flight-path measurement would enable determination of the polar diagram from a gliding flight. Since then he has endeavored to obtain accurate flight measurements by means of kinetograph (motion-picture camera). Different methods of accomplishing this are presented.

  7. Path Pascal

    NASA Technical Reports Server (NTRS)

    Campbell, R. H.; Kolstad, R. B.; Holle, D. F.; Miller, T. J.; Krause, P.; Horton, K.; Macke, T.

    1983-01-01

    Path Pascal is high-level experimental programming language based on PASCAL, which incorporates extensions for systems and real-time programming. Pascal is extended to treat real-time concurrent systems.

  8. Total energy based flight control system

    NASA Technical Reports Server (NTRS)

    Lambregts, Antonius A. (Inventor)

    1985-01-01

    An integrated aircraft longitudinal flight control system uses a generalized thrust and elevator command computation (38), which accepts flight path angle, longitudinal acceleration command signals, along with associated feedback signals, to form energy rate error (20) and energy rate distribution error (18) signals. The engine thrust command is developed (22) as a function of the energy rate distribution error and the elevator position command is developed (26) as a function of the energy distribution error. For any vertical flight path and speed mode the outerloop errors are normalized (30, 34) to produce flight path angle and longitudinal acceleration commands. The system provides decoupled flight path and speed control for all control modes previously provided by the longitudinal autopilot, autothrottle and flight management systems.

  9. AFMS Flight Path: Building Future Leaders

    DTIC Science & Technology

    2009-02-12

    Better Leaders: Developing Air Force Squadron Leadership for the Next Century. National Security Program Discussion Paper Series 03-001. Cambridge, Mass...Building Better Leaders: Developing Air Force Squadron Leadership for the Next Century. National Security Program Discussion Paper Series 03‐001

  10. Autonomous Flight Safety System

    NASA Technical Reports Server (NTRS)

    Ferrell, Bob; Santuro, Steve; Simpson, James; Zoerner, Roger; Bull, Barton; Lanzi, Jim

    2004-01-01

    Autonomous Flight Safety System (AFSS) is an independent flight safety system designed for small to medium sized expendable launch vehicles launching from or needing range safety protection while overlying relatively remote locations. AFSS replaces the need for a man-in-the-loop to make decisions for flight termination. AFSS could also serve as the prototype for an autonomous manned flight crew escape advisory system. AFSS utilizes onboard sensors and processors to emulate the human decision-making process using rule-based software logic and can dramatically reduce safety response time during critical launch phases. The Range Safety flight path nominal trajectory, its deviation allowances, limit zones and other flight safety rules are stored in the onboard computers. Position, velocity and attitude data obtained from onboard global positioning system (GPS) and inertial navigation system (INS) sensors are compared with these rules to determine the appropriate action to ensure that people and property are not jeopardized. The final system will be fully redundant and independent with multiple processors, sensors, and dead man switches to prevent inadvertent flight termination. AFSS is currently in Phase III which includes updated algorithms, integrated GPS/INS sensors, large scale simulation testing and initial aircraft flight testing.

  11. Utilization of path length fuzing in the Peacekeeper Weapon System

    NASA Astrophysics Data System (ADS)

    Jackson, A. D.

    This paper presents a discussion of the utilization and implementation of path length fuzing in the Peacekeeper Weapon System. Some background information which introduces the concept of path length fuzing and discusses its applicability to the Peacekeeper is first presented. Mathematical modeling of path length fuzing is discussed, and some novel algorithms and techniques developed by the author for implementation of path length fuzing in the Peacekeeper Operational Flight Program are presented. The scope of this paper is confined to the flight software and targeting aspects of path length fuzing; details of of the fuze hardware and electronics are not addressed.

  12. Flight testing and simulation of an F-15 airplane using throttles for flight control

    NASA Technical Reports Server (NTRS)

    Burcham, Frank W., Jr.; Maine, Trindel; Wolf, Thomas

    1992-01-01

    Flight tests and simulation studies using the throttles of an F-15 airplane for emergency flight control have been conducted at the NASA Dryden Flight Research Facility. The airplane and the simulation are capable of extended up-and-away flight, using only throttles for flight path control. Initial simulation results showed that runway landings using manual throttles-only control were difficult, but possible with practice. Manual approaches flown in the airplane were much more difficult, indicating a significant discrepancy between flight and simulation. Analysis of flight data and development of improved simulation models that resolve the discrepancy are discussed. An augmented throttle-only control system that controls bank angle and flight path with appropriate feedback parameters has also been developed, evaluated in simulations, and is planned for flight in the F-15.

  13. Multiple paths in complex tasks

    NASA Technical Reports Server (NTRS)

    Galanter, Eugene; Wiegand, Thomas; Mark, Gloria

    1987-01-01

    The relationship between utility judgments of subtask paths and the utility of the task as a whole was examined. The convergent validation procedure is based on the assumption that measurements of the same quantity done with different methods should covary. The utility measures of the subtasks were obtained during the performance of an aircraft flight controller navigation task. Analyses helped decide among various models of subtask utility combination, whether the utility ratings of subtask paths predict the whole tasks utility rating, and indirectly, whether judgmental models need to include the equivalent of cognitive noise.

  14. Flight evaluation: Ohio University omega receiver base

    NASA Technical Reports Server (NTRS)

    Chamberlin, K. A.; Lilley, R. W.; Salter, R. J.

    1974-01-01

    A flight evaluation is presented of the Ohio University Omega Receiver Base, developed under the NASA Tri-University Program in Air Transportation, to provide a vehicle for the transfer of flight-test data to NASA and to other participants in the Tri-University program. Chart recordings of flight data are given, along with chronological listings of significant events which occurred during the flight. Digital data was prepared in data-processing card form for distribution. Data include phase measurements from all eight Omega time-slots for the duration of the flight, plus event marks which serve to correlate the phase data with flight-path documentation.

  15. Last Flight for GRAIL's Twin Spacecraft

    NASA Video Gallery

    This animation shows the final flight path for NASA’s twin GravityRecovery and Interior Laboratory (GRAIL) mission spacecraft, which willimpact the moon on Dec. 17, 2012, around 2:28 p.m. PST. ...

  16. Advanced transport operating system software upgrade: Flight management/flight controls software description

    NASA Technical Reports Server (NTRS)

    Clinedinst, Winston C.; Debure, Kelly R.; Dickson, Richard W.; Heaphy, William J.; Parks, Mark A.; Slominski, Christopher J.; Wolverton, David A.

    1988-01-01

    The Flight Management/Flight Controls (FM/FC) software for the Norden 2 (PDP-11/70M) computer installed on the NASA 737 aircraft is described. The software computes the navigation position estimates, guidance commands, those commands to be issued to the control surfaces to direct the aircraft in flight based on the modes selected on the Advanced Guidance Control System (AGSC) mode panel, and the flight path selected via the Navigation Control/Display Unit (NCDU).

  17. Flight in low-level wind shear

    NASA Technical Reports Server (NTRS)

    Frost, W.

    1983-01-01

    Results of studies of wind shear hazard to aircraft operation are summarized. Existing wind shear profiles currently used in computer and flight simulator studies are reviewed. The governing equations of motion for an aircraft are derived incorporating the variable wind effects. Quantitative discussions of the effects of wind shear on aircraft performance are presented. These are followed by a review of mathematical solutions to both the linear and nonlinear forms of the governing equations. Solutions with and without control laws are presented. The application of detailed analysis to develop warning and detection systems based on Doppler radar measuring wind speed along the flight path is given. A number of flight path deterioration parameters are defined and evaluated. Comparison of computer-predicted flight paths with those measured in a manned flight simulator is made. Some proposed airborne and ground-based wind shear hazard warning and detection systems are reviewed. The advantages and disadvantages of both types of systems are discussed.

  18. 75 FR 22519 - Airworthiness Directives; Honeywell International Inc., Primus EPIC and Primus APEX Flight...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-04-29

    ... its scheduled flight path, and result in possible collision with other aircraft or terrain. DATES... transport airplanes: Chip Adam, Flight Test Pilot, Flight Test Branch, ANM-160L, FAA, Los Angeles Aircraft... during flight. Because of our requirement to promote safe flight of civil aircraft and thus the...

  19. Design of energy-based terrain following flight control system

    NASA Astrophysics Data System (ADS)

    Wang, Wei; Li, Aijun; Xie, Yanwu; Tan, Jian

    2006-11-01

    Historically, aircraft longitudinal control has been realized by means of two loops: flight path (the control variable is elevator displacement) and speed control (the control variable is propulsive thrust or engine power). Both the elevator and throttle control cause coupled altitude and speed response, which exerts negative effects on longitudinal flight performance of aircraft, especially for Terrain Following(TF) flight. Energy-based method can resolve coupled problem between flight speed and path by controlling total energy rate and energy distribution rate between elevator and throttle. In this paper, energy-based control method is applied to design a TF flight control system for controlling flight altitude directly. An error control method of airspeed and altitude is adopted to eliminate the stable error of the total energy control system when decoupling control. Pitch loop and pitch rate feedback loop are designed for the system to damp the oscillatory response produced by TF system. The TF flight control system structure diagram and an aircraft point-mass energy motion model including basic control loops are given and used to simulate decoupling performance of the TF fight control system. Simulation results show that the energy-based TF flight control system can decouple flight velocity and flight path angle, exactly follow planned flight path, and greatly reduce altitude error, which is between +10m and -8m.

  20. Kuiper Belt Objects Along the Pluto Express Path

    NASA Technical Reports Server (NTRS)

    Jewitt, David C.

    1998-01-01

    The science objective of this work was to identify objects in the Kuiper Belt which will, in the 5 years following Pluto encounter, be close to the flight path of NASA's Pluto-Kuiper Express. Currently, launch is scheduled for 2004 with a flight time of about 1 decade. Early identification of post-Pluto targets is important for mission design and orbit refinement. An object or objects close enough to the flight path can be visited and studied at high resolution, using only residual gas in the thrusters to affect a close encounter.

  1. Understanding Flight

    SciTech Connect

    Anderson, David

    2001-01-31

    Through the years the explanation of flight has become mired in misconceptions that have become dogma. Wolfgang Langewiesche, the author of 'Stick and Rudder' (1944) got it right when he wrote: 'Forget Bernoulli's Theorem'. A wing develops lift by diverting (from above) a lot of air. This is the same way that a propeller produces thrust and a helicopter produces lift. Newton's three laws and a phenomenon called the Coanda effect explain most of it. With an understanding of the real physics of flight, many things become clear. Inverted flight, symmetric wings, and the flight of insects are obvious. It is easy to understand the power curve, high-speed stalls, and the effect of load and altitude on the power requirements for lift. The contribution of wing aspect ratio on the efficiency of a wing, and the true explanation of ground effect will also be discussed.

  2. Advanced flight computer. Special study

    NASA Technical Reports Server (NTRS)

    Coo, Dennis

    1995-01-01

    This report documents a special study to define a 32-bit radiation hardened, SEU tolerant flight computer architecture, and to investigate current or near-term technologies and development efforts that contribute to the Advanced Flight Computer (AFC) design and development. An AFC processing node architecture is defined. Each node may consist of a multi-chip processor as needed. The modular, building block approach uses VLSI technology and packaging methods that demonstrate a feasible AFC module in 1998 that meets that AFC goals. The defined architecture and approach demonstrate a clear low-risk, low-cost path to the 1998 production goal, with intermediate prototypes in 1996.

  3. The absolute path command

    SciTech Connect

    Moody, A.

    2012-05-11

    The ap command traveres all symlinks in a given file, directory, or executable name to identify the final absolute path. It can print just the final path, each intermediate link along with the symlink chan, and the permissions and ownership of each directory component in the final path. It has functionality similar to "which", except that it shows the final path instead of the first path. It is also similar to "pwd", but it can provide the absolute path to a relative directory from the current working directory.

  4. Post-Flight Analysis of GPSR Performance During Orion Exploration Flight Test 1

    NASA Technical Reports Server (NTRS)

    Barker, Lee; Mamich, Harvey; McGregor, John

    2016-01-01

    On 5 December 2014, the first test flight of the Orion Multi-Purpose Crew Vehicle executed a unique and challenging flight profile including an elevated re-entry velocity and steeper flight path angle to envelope lunar re-entry conditions. A new navigation system including a single frequency (L1) GPS receiver was evaluated for use as part of the redundant navigation system required for human space flight. The single frequency receiver was challenged by a highly dynamic flight environment including flight above low Earth orbit, as well as single frequency operation with ionospheric delay present. This paper presents a brief description of the GPS navigation system, an independent analysis of flight telemetry data, and evaluation of the GPSR performance, including evaluation of the ionospheric model employed to supplement the single frequency receiver. Lessons learned and potential improvements will be discussed.

  5. Flight Simulation.

    DTIC Science & Technology

    1986-09-01

    PROCEEDINGS No.408 Flight Simulation DTIC !ELECTE NOVO505s ’ D -J DISTRIBUTION AND AVAILABILITY I I •k i nimy fle-"-- THE MISSION OF AGARI) The mission of...recherche. Ie d ~veloppement et lentrainement. Les objectifs du symposium de la commmission m~canique de vol de L’AGARD 6taient de fournir une description...tttbution Availjbiily CcodeS AvailI a.- d or Dist Spe~cial FLIGHT MECHANICS PANEL OFFICERS Chairman: Dr Ing. P.Hamcl Deputy Chairman: Dr Ing. A.Filisetti

  6. Flight directors for STOl aircraft

    NASA Technical Reports Server (NTRS)

    Rabin, U. H.

    1983-01-01

    Flight director logic for flight path and airspeed control of a powered-lift STOL aircraft in the approach, transition, and landing configurations are developed. The methods for flight director design are investigated. The first method is based on the Optimal Control Model (OCM) of the pilot. The second method, proposed here, uses a fixed dynamic model of the pilot in a state space formulation similar to that of the OCM, and includes a pilot work-load metric. Several design examples are presented with various aircraft, sensor, and control configurations. These examples show the strong impact of throttle effectiveness on the performance and pilot work-load associated with manual control of powered-lift aircraft during approach. Improved performed and reduced pilot work-load can be achieved by using direct-lift-control to increase throttle effectiveness.

  7. 14 CFR 25.1329 - Flight guidance system.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... in the flight path. This applies to both fault-free operation and in the event of a malfunction, and... armed modes, transitions, and reversions. Selector switch position is not an acceptable means...

  8. 14 CFR 25.1329 - Flight guidance system.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... in the flight path. This applies to both fault-free operation and in the event of a malfunction, and... armed modes, transitions, and reversions. Selector switch position is not an acceptable means...

  9. Measurement resolution of noise directivity patterns from acoustic flight tests

    NASA Technical Reports Server (NTRS)

    Conner, David A.

    1989-01-01

    The measurement resolution of noise directivity patterns from acoustic flight tests was investigated. Directivity angle resolution is affected by the data reduction parameters, the aircraft velocity and flyover altitude, and by deviations of the aircraft from the desired flight path. Equations are developed which determine bounds for the lateral and longitudinal directivity angle resolution as a function of the nominal directivity angle. The equations are applied to a flight test data base and the effects of several flight conditions and data reduction parameters on the directivity angle resolution are presented. The maximum directivity angle resolution typically occurs when the aircraft is at or near the overhead position. In general, directivity angle resolution improves with decreasing velocity, increasing altitude, increasing sampling rate, decreasing block size, and decreasing block averages. Deviations from the desired ideal flight path will increase the resolution. For the flight experiment considered in this study, an average of two flyovers were required at each test condition to obtain an acceptable flight path. The ability of the pilot to maintain the flight track improved with decreasing altitude, decreasing velocity, and practice. Due to the prevailing wind conditions, yaw angles of as much as 20 deg were required to maintain the desired flight path.

  10. System and Method for Aiding Pilot Preview, Rehearsal, Review, and Real-Time Visual Acquisition of Flight Mission Progress

    NASA Technical Reports Server (NTRS)

    Prinzel, III, Lawrence J. (Inventor); Pope, Alan T. (Inventor); Williams, Steven P. (Inventor); Bailey, Randall E. (Inventor); Arthur, Jarvis J. (Inventor); Kramer, Lynda J. (Inventor); Schutte, Paul C. (Inventor)

    2012-01-01

    Embodiments of the invention permit flight paths (current and planned) to be viewed from various orientations to provide improved path and terrain awareness via graphical two-dimensional or three-dimensional perspective display formats. By coupling the flight path information with a terrain database, uncompromising terrain awareness relative to the path and ownship is provided. In addition, missed approaches, path deviations, and any navigational path can be reviewed and rehearsed before performing the actual task. By rehearsing a particular mission, check list items can be reviewed, terrain awareness can be highlighted, and missed approach procedures can be discussed by the flight crew. Further, the use of Controller Pilot Datalink Communications enables data-linked path, flight plan changes, and Air Traffic Control requests to be integrated into the flight display of the present invention.

  11. Radiological Assistance Program Flight Planning Tool

    SciTech Connect

    Messick, C.; Pham, M.; Ridgeway, J.; Smith, R.

    2011-12-19

    The Radiological Assitance Program (RAP) is the National Nuclear Security Administration's (NNSA) first responder to radiological emergencies. RAP's mission is to identify and minimize radiological hazards, as well as provide radiological emergency response and technical advice to decision makers. One tool commonly used is aerial radiation detection equipment. During a response getting this equipment in the right place quickly is critical. The RAP Flight Planning Tool (a ArcGIS 10 Desktop addin) helps minimize this response time and provides specific customizable flight path information to the flight staff including maps, coordinates, and azimuths.

  12. The universal path integral

    NASA Astrophysics Data System (ADS)

    Lloyd, Seth; Dreyer, Olaf

    2016-02-01

    Path integrals calculate probabilities by summing over classical configurations of variables such as fields, assigning each configuration a phase equal to the action of that configuration. This paper defines a universal path integral, which sums over all computable structures. This path integral contains as sub-integrals all possible computable path integrals, including those of field theory, the standard model of elementary particles, discrete models of quantum gravity, string theory, etc. The universal path integral possesses a well-defined measure that guarantees its finiteness. The probabilities for events corresponding to sub-integrals can be calculated using the method of decoherent histories. The universal path integral supports a quantum theory of the universe in which the world that we see around us arises out of the interference between all computable structures.

  13. Pulled Motzkin paths

    NASA Astrophysics Data System (ADS)

    Janse van Rensburg, E. J.

    2010-08-01

    In this paper the models of pulled Dyck paths in Janse van Rensburg (2010 J. Phys. A: Math. Theor. 43 215001) are generalized to pulled Motzkin path models. The generating functions of pulled Motzkin paths are determined in terms of series over trinomial coefficients and the elastic response of a Motzkin path pulled at its endpoint (see Orlandini and Whittington (2004 J. Phys. A: Math. Gen. 37 5305-14)) is shown to be R(f) = 0 for forces pushing the endpoint toward the adsorbing line and R(f) = f(1 + 2cosh f))/(2sinh f) → f as f → ∞, for forces pulling the path away from the X-axis. In addition, the elastic response of a Motzkin path pulled at its midpoint is shown to be R(f) = 0 for forces pushing the midpoint toward the adsorbing line and R(f) = f(1 + 2cosh (f/2))/sinh (f/2) → 2f as f → ∞, for forces pulling the path away from the X-axis. Formal combinatorial identities arising from pulled Motzkin path models are also presented. These identities are the generalization of combinatorial identities obtained in directed paths models to their natural trinomial counterparts.

  14. Path Integrals and Hamiltonians

    NASA Astrophysics Data System (ADS)

    Baaquie, Belal E.

    2014-03-01

    1. Synopsis; Part I. Fundamental Principles: 2. The mathematical structure of quantum mechanics; 3. Operators; 4. The Feynman path integral; 5. Hamiltonian mechanics; 6. Path integral quantization; Part II. Stochastic Processes: 7. Stochastic systems; Part III. Discrete Degrees of Freedom: 8. Ising model; 9. Ising model: magnetic field; 10. Fermions; Part IV. Quadratic Path Integrals: 11. Simple harmonic oscillators; 12. Gaussian path integrals; Part V. Action with Acceleration: 13. Acceleration Lagrangian; 14. Pseudo-Hermitian Euclidean Hamiltonian; 15. Non-Hermitian Hamiltonian: Jordan blocks; 16. The quartic potential: instantons; 17. Compact degrees of freedom; Index.

  15. Kuiper Belt Objects Along the Pluto-Express Path

    NASA Technical Reports Server (NTRS)

    Jewitt, David (Principal Investigator)

    1997-01-01

    The science objective of this work is to identify objects in the Kuiper Belt which will, in the 5 years following Pluto encounter, be close to the flight path of NASA's Pluto Express. Our hope is that we will find a Kuiper Belt object or objects close enough that a spacecraft flyby will be possible. If we find a suitable object, the science yield of Pluto Express will be substantially enhanced. The density of objects in the Kuiper Belt is such that we are reasonably likely to find an object close enough to the flight path that on-board gas thrusters can effect a close encounter.

  16. Flight evaluation of advanced flight control systems and cockpit displays for powered-lift STOL Aircraft

    NASA Technical Reports Server (NTRS)

    Franklin, J. A.; Smith, D. W.; Watson, D. M.; Warner, D. N., Jr.; Innis, R. C.; Hardy, G. H.

    1976-01-01

    A flight research program was conducted to assess the improvements, in longitudinal path control during a STOL approach and landing, that can be achieved with manual and automatic control system concepts and cockpit displays with various degrees of complexity. NASA-Ames powered-lift Augmentor Wing Research Aircraft was used in the research program. Satisfactory flying qualities were demonstrated for selected stabilization and command augmentation systems and flight director combinations. The ability of the pilot to perform precise landings at low touchdown sink rates with a gentle flare maneuver was also achieved. The path-control improvement is considered to be applicable to other powered-lift aircraft configurations.

  17. Optimal nonlinear estimation for aircraft flight control in wind shear

    NASA Technical Reports Server (NTRS)

    Mulgund, Sandeep S.

    1994-01-01

    The most recent results in an ongoing research effort at Princeton in the area of flight dynamics in wind shear are described. The first undertaking in this project was a trajectory optimization study. The flight path of a medium-haul twin-jet transport aircraft was optimized during microburst encounters on final approach. The assumed goal was to track a reference climb rate during an aborted landing, subject to a minimum airspeed constraint. The results demonstrated that the energy loss through the microburst significantly affected the qualitative nature of the optimal flight path. In microbursts of light to moderate strength, the aircraft was able to track the reference climb rate successfully. In severe microbursts, the minimum airspeed constraint in the optimization forced the aircraft to settle on a climb rate smaller than the target. A tradeoff was forced between the objectives of flight path tracking and stall prevention.

  18. A study of interior noise levels, noise sources and transmission paths in light aircraft

    NASA Technical Reports Server (NTRS)

    Hayden, R. E.; Murray, B. S.; Theobald, M. A.

    1983-01-01

    The interior noise levels and spectral characteristics of 18 single-and twin-engine propeller-driven light aircraft, and source-path diagnosis of a single-engine aircraft which was considered representative of a large part of the fleet were studied. The purpose of the flight surveys was to measure internal noise levels and identify principal noise sources and paths under a carefully controlled and standardized set of flight procedures. The diagnostic tests consisted of flights and ground tests in which various parts of the aircraft, such as engine mounts, the engine compartment, exhaust pipe, individual panels, and the wing strut were instrumented to determine source levels and transmission path strengths using the transfer function technique. Predominant source and path combinations are identified. Experimental techniques are described. Data, transfer function calculations to derive source-path contributions to the cabin acoustic environment, and implications of the findings for noise control design are analyzed.

  19. In-flight turbulence benefits soaring birds

    USGS Publications Warehouse

    Mallon, Julie M; Bildstein, Keith L.; Katzner, Todd E.

    2015-01-01

    Birds use atmospheric updrafts to subsidize soaring flight. We observed highly variable soaring flight by Black Vultures (Coragyps atratus) and Turkey Vultures (Cathartes aura) in Virginia, USA, that was inconsistent with published descriptions of terrestrial avian flight. Birds engaging in this behavior regularly deviated vertically and horizontally from linear flight paths. We observed the soaring flight behavior of these 2 species to understand why they soar in this manner and when this behavior occurs. Vultures used this type of soaring mainly at low altitudes (<50 m), along forest edges, and when conditions were poor for thermal development. Because of the tortuous nature of this flight, we describe it as “contorted soaring.” The primary air movement suitable to subsidize flight at this altitude and under these atmospheric conditions is small-scale, shear-induced turbulence, which our results suggest can be an important resource for soaring birds because it permits continuous subsidized flight when other types of updraft are not available.

  20. Slow Lévy flights

    NASA Astrophysics Data System (ADS)

    Boyer, Denis; Pineda, Inti

    2016-02-01

    Among Markovian processes, the hallmark of Lévy flights is superdiffusion, or faster-than-Brownian dynamics. Here we show that Lévy laws, as well as Gaussian distributions, can also be the limit distributions of processes with long-range memory that exhibit very slow diffusion, logarithmic in time. These processes are path dependent and anomalous motion emerges from frequent relocations to already visited sites. We show how the central limit theorem is modified in this context, keeping the usual distinction between analytic and nonanalytic characteristic functions. A fluctuation-dissipation relation is also derived. Our results may have important applications in the study of animal and human displacements.

  1. Design and analysis of advanced flight planning concepts

    NASA Technical Reports Server (NTRS)

    Sorensen, John A.

    1987-01-01

    The objectives of this continuing effort are to develop and evaluate new algorithms and advanced concepts for flight management and flight planning. This includes the minimization of fuel or direct operating costs, the integration of the airborne flight management and ground-based flight planning processes, and the enhancement of future traffic management systems design. Flight management (FMS) concepts are for on-board profile computation and steering of transport aircraft in the vertical plane between a city pair and along a given horizontal path. Flight planning (FPS) concepts are for the pre-flight ground based computation of the three-dimensional reference trajectory that connects the city pair and specifies the horizontal path, fuel load, and weather profiles for initializing the FMS. As part of these objectives, a new computer program called EFPLAN has been developed and utilized to study advanced flight planning concepts. EFPLAN represents an experimental version of an FPS. It has been developed to generate reference flight plans compatible as input to an FMS and to provide various options for flight planning research. This report describes EFPLAN and the associated research conducted in its development.

  2. A Path to Discovery

    ERIC Educational Resources Information Center

    Stegemoller, William; Stegemoller, Rebecca

    2004-01-01

    The path taken and the turns made as a turtle traces a polygon are examined to discover an important theorem in geometry. A unique tool, the Angle Adder, is implemented in the investigation. (Contains 9 figures.)

  3. Tortuous path chemical preconcentrator

    DOEpatents

    Manginell, Ronald P.; Lewis, Patrick R.; Adkins, Douglas R.; Wheeler, David R.; Simonson, Robert J.

    2010-09-21

    A non-planar, tortuous path chemical preconcentrator has a high internal surface area having a heatable sorptive coating that can be used to selectively collect and concentrate one or more chemical species of interest from a fluid stream that can be rapidly released as a concentrated plug into an analytical or microanalytical chain for separation and detection. The non-planar chemical preconcentrator comprises a sorptive support structure having a tortuous flow path. The tortuosity provides repeated twists, turns, and bends to the flow, thereby increasing the interfacial contact between sample fluid stream and the sorptive material. The tortuous path also provides more opportunities for desorption and readsorption of volatile species. Further, the thermal efficiency of the tortuous path chemical preconcentrator is comparable or superior to the prior non-planar chemical preconcentrator. Finally, the tortuosity can be varied in different directions to optimize flow rates during the adsorption and desorption phases of operation of the preconcentrator.

  4. Flight Path Control Design for the Cassini Solstice Mission

    NASA Technical Reports Server (NTRS)

    Ballard, Christopher G.; Ionasescu, Rodica

    2011-01-01

    The Cassini spacecraft has been in orbit around Saturn for just over 7 years, with a planned 7-year extension, called the Solstice Mission, which started on September 27, 2010. The Solstice Mission includes 205 maneuvers and 70 flybys which consist of the moons Titan, Enceladus, Dione, and Rhea. This mission is designed to use all available propellant with a statistical margin averaging 0.6 m/s per encounter, and the work done to prove and ensure the viability of this margin is highlighted in this paper.

  5. AN ANALYSIS OF TERMINAL FLIGHT PATH CONTROL IN CARRIER LANDING

    DTIC Science & Technology

    Fresnel lens optical landing system/(FLOLS)/pilot/aircraft system, considering deck motions and air turbulence inputs. Performance of this model in terms of terminal conditions in the vertical plane (ramp clearance, impact velocity, dispersion of the touchdown point) and aircraft longitudinal motions in the groove prior to touchdown is consistent with and validated by actual performance. The terminal dispersions are statistically combined to yield probabilities of potential ramp strikes, landing gear failures, and bolters, which, when put through a simplified pilot/LSO

  6. 14 CFR 23.61 - Takeoff flight path.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ...) of this section, reduced at each point by a gradient of climb equal to— (1) 0.8 percent for two... airplanes. (c) The prescribed reduction in climb gradient may be applied as an equivalent reduction...

  7. 14 CFR 23.61 - Takeoff flight path.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... point by a gradient of climb equal to— (1) 0.8 percent for two-engine airplanes; (2) 0.9 percent for... climb gradient may be applied as an equivalent reduction in acceleration along that part of the...

  8. 14 CFR 23.61 - Takeoff flight path.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... paragraph (a) of this section, reduced at each point by a gradient of climb equal to— (1) 0.8 percent for... airplanes. (c) The prescribed reduction in climb gradient may be applied as an equivalent reduction...

  9. 14 CFR 23.61 - Takeoff flight path.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ...) of this section, reduced at each point by a gradient of climb equal to— (1) 0.8 percent for two... airplanes. (c) The prescribed reduction in climb gradient may be applied as an equivalent reduction...

  10. 14 CFR 23.61 - Takeoff flight path.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... paragraph (a) of this section, reduced at each point by a gradient of climb equal to— (1) 0.8 percent for... airplanes. (c) The prescribed reduction in climb gradient may be applied as an equivalent reduction...

  11. Green Flight Challenge

    NASA Video Gallery

    The CAFE Green Flight Challenge sponsored by Google will be held at the CAFE Foundation Flight Test Center at Charles M. Schulz Sonoma County Airport in Santa Rosa, Calif. The Green Flight Challeng...

  12. Turbulence flight director analysis and preliminary simulation

    NASA Technical Reports Server (NTRS)

    Johnson, D. E.; Klein, R. E.

    1974-01-01

    A control column and trottle flight director display system is synthesized for use during flight through severe turbulence. The column system is designed to minimize airspeed excursions without overdriving attitude. The throttle system is designed to augment the airspeed regulation and provide an indication of the trim thrust required for any desired flight path angle. Together they form an energy management system to provide harmonious display indications of current aircraft motions and required corrective action, minimize gust upset tendencies, minimize unsafe aircraft excursions, and maintain satisfactory ride qualities. A preliminary fixed-base piloted simulation verified the analysis and provided a shakedown for a more sophisticated moving-base simulation to be accomplished next. This preliminary simulation utilized a flight scenario concept combining piloting tasks, random turbulence, and discrete gusts to create a high but realistic pilot workload conducive to pilot error and potential upset. The turbulence director (energy management) system significantly reduced pilot workload and minimized unsafe aircraft excursions.

  13. NASA's Flight Opportunities Program

    NASA Video Gallery

    NASA's Flight Opportunities Program is facilitating low-cost access to suborbital space, where researchers can test technologies using commercially developed vehicles. Suborbital flights can quickl...

  14. Flexible-Path Human Exploration

    NASA Technical Reports Server (NTRS)

    Sherwood, B.; Adler, M.; Alkalai, L.; Burdick, G.; Coulter, D.; Jordan, F.; Naderi, F.; Graham, L.; Landis, R.; Drake, B.; Hoffman, S.; Grunsfeld, J.; Seery, B. D.

    2010-01-01

    In the fourth quarter of 2009 an in-house, multi-center NASA study team briefly examined "Flexible Path" concepts to begin understanding characteristics, content, and roles of potential missions consistent with the strategy proposed by the Augustine Committee. We present an overview of the study findings. Three illustrative human/robotic mission concepts not requiring planet surface operations are described: assembly of very large in-space telescopes in cis-lunar space; exploration of near Earth objects (NEOs); exploration of Mars' moon Phobos. For each, a representative mission is described, technology and science objectives are outlined, and a basic mission operations concept is quantified. A fourth type of mission, using the lunar surface as preparation for Mars, is also described. Each mission's "capability legacy" is summarized. All four illustrative missions could achieve NASA's stated human space exploration objectives and advance human space flight toward Mars surface exploration. Telescope assembly missions would require the fewest new system developments. NEO missions would offer a wide range of deep-space trip times between several months and two years. Phobos exploration would retire several Marsclass risks, leaving another large remainder set (associated with entry, descent, surface operations, and ascent) for retirement by subsequent missions. And extended lunar surface operations would build confidence for Mars surface missions by addressing a complementary set of risks. Six enabling developments (robotic precursors, ISS exploration testbed, heavy-lift launch, deep-space-capable crew capsule, deep-space habitat, and reusable in-space propulsion stage) would apply across multiple program sequence options, and thus could be started even without committing to a specific mission sequence now. Flexible Path appears to be a viable strategy, with meaningful and worthy mission content.

  15. Stirling to Flight Initiative

    NASA Technical Reports Server (NTRS)

    Hibbard, Kenneth E.; Mason, Lee S.; Ndu, Obi; Smith, Clayton; Withrow, James P.

    2016-01-01

    Flight (S2F) initiative with the objective of developing a 100-500 We Stirling generator system. Additionally, a different approach is being devised for this initiative to avoid pitfalls of the past, and apply lessons learned from the recent ASRG experience. Two key aspects of this initiative are a Stirling System Technology Maturation Effort, and a Surrogate Mission Team (SMT) intended to provide clear mission pull and requirements context. The S2F project seeks to lead directly into a DOE flight system development of a new SRG. This paper will detail the proposed S2F initiative, and provide specifics on the key efforts designed to pave a forward path for bringing Stirling technology to flight.

  16. Flight Test Series 3: Flight Test Report

    NASA Technical Reports Server (NTRS)

    Marston, Mike; Sternberg, Daniel; Valkov, Steffi

    2015-01-01

    This document is a flight test report from the Operational perspective for Flight Test Series 3, a subpart of the Unmanned Aircraft System (UAS) Integration in the National Airspace System (NAS) project. Flight Test Series 3 testing began on June 15, 2015, and concluded on August 12, 2015. Participants included NASA Ames Research Center, NASA Armstrong Flight Research Center, NASA Glenn Research Center, NASA Langley Research center, General Atomics Aeronautical Systems, Inc., and Honeywell. Key stakeholders analyzed their System Under Test (SUT) in two distinct configurations. Configuration 1, known as Pairwise Encounters, was subdivided into two parts: 1a, involving a low-speed UAS ownship and intruder(s), and 1b, involving a high-speed surrogate ownship and intruder. Configuration 2, known as Full Mission, involved a surrogate ownship, live intruder(s), and integrated virtual traffic. Table 1 is a summary of flights for each configuration, with data collection flights highlighted in green. Section 2 and 3 of this report give an in-depth description of the flight test period, aircraft involved, flight crew, and mission team. Overall, Flight Test 3 gathered excellent data for each SUT. We attribute this successful outcome in large part from the experience that was acquired from the ACAS Xu SS flight test flown in December 2014. Configuration 1 was a tremendous success, thanks to the training, member participation, integration/testing, and in-depth analysis of the flight points. Although Configuration 2 flights were cancelled after 3 data collection flights due to various problems, the lessons learned from this will help the UAS in the NAS project move forward successfully in future flight phases.

  17. Design and Testing of a Low Noise Flight Guidance Concept

    NASA Technical Reports Server (NTRS)

    Williams, David H.; Oseguera-Lohr, Rosa M.; Lewis, Elliot T.

    2004-01-01

    A flight guidance concept was developed to assist in flying continuous descent approach (CDA) procedures designed to lower the noise under the flight path of jet transport aircraft during arrival operations at an airport. The guidance consists of a trajectory prediction algorithm that was tuned to produce a high-efficiency, low noise flight profile with accompanying autopilot and flight display elements needed by the flight control system and pilot to fly the approach. A key component of the flight guidance was a real-time display of energy error relative to the predicted flight path. The guidance was integrated with the conventional Flight Management System (FMS) guidance of a modern jet transport airplane and tested in a high fidelity flight simulation. A charted arrival procedure, which allowed flying conventional arrivals, CDA arrivals with standard guidance, and CDA arrivals with the new low noise guidance, was developed to assist in the testing and evaluation of the low noise guidance concept. Results of the simulation testing showed the low noise guidance was easy to use by airline pilot test subjects and effective in achieving the desired noise reduction. Noise under the flight path was reduced by at least 2 decibels in Sound Exposure Level (SEL) at distances from about 3 nautical miles out to about 17.5 nautical miles from the runway, with a peak reduction of 8.5 decibels at about 10.5 nautical miles. Fuel consumption was also reduced by about 17% for the LNG conditions compared to baseline runs for the same flight distance. Pilot acceptance and understanding of the guidance was quite high with favorable comments and ratings received from all test subjects.

  18. Precision Cleaning - Path to Premier

    NASA Technical Reports Server (NTRS)

    Mackler, Scott E.

    2008-01-01

    ITT Space Systems Division s new Precision Cleaning facility provides critical cleaning and packaging of aerospace flight hardware and optical payloads to meet customer performance requirements. The Precision Cleaning Path to Premier Project was a 2007 capital project and is a key element in the approved Premier Resource Management - Integrated Supply Chain Footprint Optimization Project. Formerly precision cleaning was located offsite in a leased building. A new facility equipped with modern precision cleaning equipment including advanced process analytical technology and improved capabilities was designed and built after outsourcing solutions were investigated and found lacking in ability to meet quality specifications and schedule needs. SSD cleans parts that can range in size from a single threaded fastener all the way up to large composite structures. Materials that can be processed include optics, composites, metals and various high performance coatings. We are required to provide verification to our customers that we have met their particulate and molecular cleanliness requirements and we have that analytical capability in this new facility. The new facility footprint is approximately half the size of the former leased operation and provides double the amount of throughput. Process improvements and new cleaning equipment are projected to increase 1st pass yield from 78% to 98% avoiding $300K+/yr in rework costs. Cost avoidance of $350K/yr will result from elimination of rent, IT services, transportation, and decreased utility costs. Savings due to reduced staff expected to net $4-500K/yr.

  19. Mobile transporter path planning

    NASA Technical Reports Server (NTRS)

    Baffes, Paul; Wang, Lui

    1990-01-01

    The use of a genetic algorithm (GA) for solving the mobile transporter path planning problem is investigated. The mobile transporter is a traveling robotic vehicle proposed for the space station which must be able to reach any point of the structure autonomously. Elements of the genetic algorithm are explored in both a theoretical and experimental sense. Specifically, double crossover, greedy crossover, and tournament selection techniques are examined. Additionally, the use of local optimization techniques working in concert with the GA are also explored. Recent developments in genetic algorithm theory are shown to be particularly effective in a path planning problem domain, though problem areas can be cited which require more research.

  20. Flight projects overview

    NASA Technical Reports Server (NTRS)

    Levine, Jack

    1988-01-01

    Information is given in viewgraph form on the activities of the Flight Projects Division of NASA's Office of Aeronautics and Space Technology. Information is given on space research and technology strategy, current space flight experiments, the Long Duration Exposure Facility, the Orbiter Experiment Program, the Lidar In-Space Technology Experiment, the Ion Auxiliary Propulsion System, the Arcjet Flight Experiment, the Telerobotic Intelligent Interface Flight Experiment, the Cryogenic Fluid Management Flight Experiment, the Industry/University In-Space Flight Experiments, and the Aeroassist Flight Experiment.

  1. Development of flying qualities criteria for single pilot instrument flight operations

    NASA Technical Reports Server (NTRS)

    Bar-Gill, A.; Nixon, W. B.; Miller, G. E.

    1982-01-01

    Flying qualities criteria for Single Pilot Instrument Flight Rule (SPIFR) operations were investigated. The ARA aircraft was modified and adapted for SPIFR operations. Aircraft configurations to be flight-tested were chosen and matched on the ARA in-flight simulator, implementing modern control theory algorithms. Mission planning and experimental matrix design were completed. Microprocessor software for the onboard data acquisition system was debugged and flight-tested. Flight-path reconstruction procedure and the associated FORTRAN program were developed. Algorithms associated with the statistical analysis of flight test results and the SPIFR flying qualities criteria deduction are discussed.

  2. Design of an advanced flight planning system

    NASA Technical Reports Server (NTRS)

    Sorensen, J. A.; Goka, T.

    1985-01-01

    The demand for both fuel conservation and four-dimensional traffic management require that the preflight planning process be designed to account for advances in airborne flight management and weather forecasting. The steps and issues in designing such an advanced flight planning system are presented. Focus is placed on the different optimization options for generating the three-dimensional reference path. For the cruise phase, one can use predefined jet routes, direct routes based on a network of evenly spaced grid points, or a network where the grid points are existing navaid locations. Each choice has its own problem in determining an optimum solution. Finding the reference path is further complicated by choice of cruise altitude levels, use of a time-varying weather field, and requiring a fixed time-of-arrival (four-dimensional problem).

  3. An Unplanned Path

    ERIC Educational Resources Information Center

    McGarvey, Lynn M.; Sterenberg, Gladys Y.; Long, Julie S.

    2013-01-01

    The authors elucidate what they saw as three important challenges to overcome along the path to becoming elementary school mathematics teacher leaders: marginal interest in math, low self-confidence, and teaching in isolation. To illustrate how these challenges were mitigated, they focus on the stories of two elementary school teachers--Laura and…

  4. Gas path seal

    NASA Technical Reports Server (NTRS)

    Bill, R. C.; Johnson, R. D. (Inventor)

    1979-01-01

    A gas path seal suitable for use with a turbine engine or compressor is described. A shroud wearable or abradable by the abrasion of the rotor blades of the turbine or compressor shrouds the rotor bades. A compliant backing surrounds the shroud. The backing is a yieldingly deformable porous material covered with a thin ductile layer. A mounting fixture surrounds the backing.

  5. Optimal symmetric flight with an intermediate vehicle model

    NASA Technical Reports Server (NTRS)

    Menon, P. K. A.; Kelley, H. J.; Cliff, E. M.

    1983-01-01

    Optimal flight in the vertical plane with a vehicle model intermediate in complexity between the point-mass and energy models is studied. Flight-path angle takes on the role of a control variable. Range-open problems feature subarcs of vertical flight and singular subarcs. The class of altitude-speed-range-time optimization problems with fuel expenditure unspecified is investigated and some interesting phenomena uncovered. The maximum-lift-to-drag glide appears as part of the family, final-time-open, with appropriate initial and terminal transient exceeding level-flight drag, some members exhibiting oscillations. Oscillatory paths generally fail the Jacobi test for durations exceeding a period and furnish a minimum only for short-duration problems.

  6. Tentative civil airworthiness flight criteria for powered-lift transports

    NASA Technical Reports Server (NTRS)

    Hynes, C. S.; Scott, B. C.

    1976-01-01

    Representatives of the U.S., British, French, and Canadian airworthiness authorities participated in a NASA/FAA program to formulate tentative civil airworthiness flight criteria for powered-lift transports. The ultimate limits of the flight envelope are defined by boundaries in the airspeed/path-angle plane. Angle of attack and airspeed margins applied to these ultimate limits provide protection against both atmospheric disturbances and disturbances resulting from pilot actions or system variability, but do not ensure maneuvering capability directly, as the 30% speed margin does for conventional transports. Separate criteria provide for direct demonstration of adequate capability for approach path control, flare and landing, and for go-around. Demonstration maneuvers are proposed, and appropriate abuses and failures are suggested. Taken together, these criteria should permit selection of appropriate operating points within the flight envelopes for the approach, landing, and go-around flight phases which are likely to be most critical for powered-lift aircraft.

  7. Real-Time Trajectory Generation for Autonomous Nonlinear Flight Systems

    DTIC Science & Technology

    2006-04-01

    Real-Time Trajectory Generation for Autonomous Nonlinear Flight Systems AF02T002 Phase II Final Report Contract No. FA9550-04-C-0032 Principal...3. REPORT TYPE AND DATES COVERED Final Report for 14 April 2004-14 April 2006 Real-Time Trajectory Generation for Autonomous Nonlinear Flight...A 13. ABSTRACT (Maximum 200 Words) Unmanned aerial vehicle and smart munition systems need robust, real-time path generation and

  8. Feasibility Study for Integrated Flight Trajectory Control (Fighter).

    DTIC Science & Technology

    1979-11-01

    ntamber) Flight Trajectory C.ntrol Control Law Development Profile Synthesis Tactical Situation Display Four -Dimensional Navigation Vertical Situation...realtime trajectory generation was developed as a vital part of the total solution. This trajectory, generator operates in four dimensions, X, Y...FLIGHT PROFILE SYNTHESIS 5-1 5.1 Four -Dimensional Trajectory Generator 5-1 5.1.1 Waypoint Parameters 5-1 5.1.2 Threat Avoidance 5-2 5.1.3 Horizontal Path

  9. Flight Test Engineering

    NASA Technical Reports Server (NTRS)

    Pavlock, Kate Maureen

    2013-01-01

    Although the scope of flight test engineering efforts may vary among organizations, all point to a common theme: flight test engineering is an interdisciplinary effort to test an asset in its operational flight environment. Upfront planning where design, implementation, and test efforts are clearly aligned with the flight test objective are keys to success. This chapter provides a top level perspective of flight test engineering for the non-expert. Additional research and reading on the topic is encouraged to develop a deeper understanding of specific considerations involved in each phase of flight test engineering.

  10. Low Bandwidth Robust Controllers for Flight

    NASA Technical Reports Server (NTRS)

    Biezad, Daniel J.; Chou, Hwei-Lan

    1993-01-01

    Through throttle manipulations, engine thrust can be used for emergency flight control for multi-engine aircraft. Previous study by NASA Dryden has shown the use of throttles for emergency flight control to be very difficult. In general, manual fly-by-throttle is extremely difficult - with landing almost impossible, but control augmentation makes runway landings feasible. Flight path control using throttles-only to achieve safe emergency landing for a large jet transport airplane, Boeing 720, was investigated using Quantitative Feedback Theory (QFT). Results were compared to an augmented control developed in a previous simulation study. The control augmentation corrected the unsatisfactory open-loop characteristics by increasing system bandwidth and damping, but increasing the control bandwidth substantially proved very difficult. The augmented pitch control is robust under no or moderate turbulence. The augmented roll control is sensitive to configuration changes.

  11. Low bandwidth robust controllers for flight

    NASA Technical Reports Server (NTRS)

    Biezad, Daniel J.; Chou, Hwei-Lan

    1993-01-01

    Through throttle manipulations, engine thrust can be used for emergency flight control for multi-engine aircraft. Previous study by NASA Dryden has shown the use of throttles for emergency flight control to be very difficult. In general, manual fly-by-throttle is extremely difficult - with landing almost impossible, but control augmentation makes runway landings feasible. Flight path control using throttles-only to achieve safe emergency landing for a large jet transport airplane, Boeing 720, was investigated using Quantitative Feedback Theory (QFT). Results were compared to an augmented control developed in a previous simulation study. The control augmentation corrected the unsatisfactory open-loop characteristics by increasing system bandwidth and damping, but increasing the control bandwidth substantially proved very difficult. The augmented pitch control is robust under no or moderate turbulence. The augmented roll control is sensitive to configuration changes.

  12. Entanglement by Path Identity.

    PubMed

    Krenn, Mario; Hochrainer, Armin; Lahiri, Mayukh; Zeilinger, Anton

    2017-02-24

    Quantum entanglement is one of the most prominent features of quantum mechanics and forms the basis of quantum information technologies. Here we present a novel method for the creation of quantum entanglement in multipartite and high-dimensional systems. The two ingredients are (i) superposition of photon pairs with different origins and (ii) aligning photons such that their paths are identical. We explain the experimentally feasible creation of various classes of multiphoton entanglement encoded in polarization as well as in high-dimensional Hilbert spaces-starting only from nonentangled photon pairs. For two photons, arbitrary high-dimensional entanglement can be created. The idea of generating entanglement by path identity could also apply to quantum entities other than photons. We discovered the technique by analyzing the output of a computer algorithm. This shows that computer designed quantum experiments can be inspirations for new techniques.

  13. Entanglement by Path Identity

    NASA Astrophysics Data System (ADS)

    Krenn, Mario; Hochrainer, Armin; Lahiri, Mayukh; Zeilinger, Anton

    2017-02-01

    Quantum entanglement is one of the most prominent features of quantum mechanics and forms the basis of quantum information technologies. Here we present a novel method for the creation of quantum entanglement in multipartite and high-dimensional systems. The two ingredients are (i) superposition of photon pairs with different origins and (ii) aligning photons such that their paths are identical. We explain the experimentally feasible creation of various classes of multiphoton entanglement encoded in polarization as well as in high-dimensional Hilbert spaces—starting only from nonentangled photon pairs. For two photons, arbitrary high-dimensional entanglement can be created. The idea of generating entanglement by path identity could also apply to quantum entities other than photons. We discovered the technique by analyzing the output of a computer algorithm. This shows that computer designed quantum experiments can be inspirations for new techniques.

  14. Nonadiabatic transition path sampling

    NASA Astrophysics Data System (ADS)

    Sherman, M. C.; Corcelli, S. A.

    2016-07-01

    Fewest-switches surface hopping (FSSH) is combined with transition path sampling (TPS) to produce a new method called nonadiabatic path sampling (NAPS). The NAPS method is validated on a model electron transfer system coupled to a Langevin bath. Numerically exact rate constants are computed using the reactive flux (RF) method over a broad range of solvent frictions that span from the energy diffusion (low friction) regime to the spatial diffusion (high friction) regime. The NAPS method is shown to quantitatively reproduce the RF benchmark rate constants over the full range of solvent friction. Integrating FSSH within the TPS framework expands the applicability of both approaches and creates a new method that will be helpful in determining detailed mechanisms for nonadiabatic reactions in the condensed-phase.

  15. Preliminary test results of a flight management algorithm for fuel conservative descents in a time based metered traffic environment. [flight tests of an algorithm to minimize fuel consumption of aircraft based on flight time

    NASA Technical Reports Server (NTRS)

    Knox, C. E.; Cannon, D. G.

    1979-01-01

    A flight management algorithm designed to improve the accuracy of delivering the airplane fuel efficiently to a metering fix at a time designated by air traffic control is discussed. The algorithm provides a 3-D path with time control (4-D) for a test B 737 airplane to make an idle thrust, clean configured descent to arrive at the metering fix at a predetermined time, altitude, and airspeed. The descent path is calculated for a constant Mach/airspeed schedule from linear approximations of airplane performance with considerations given for gross weight, wind, and nonstandard pressure and temperature effects. The flight management descent algorithms and the results of the flight tests are discussed.

  16. PathMaster

    PubMed Central

    Mattie, Mark E.; Staib, Lawrence; Stratmann, Eric; Tagare, Hemant D.; Duncan, James; Miller, Perry L.

    2000-01-01

    Objective: Currently, when cytopathology images are archived, they are typically stored with a limited text-based description of their content. Such a description inherently fails to quantify the properties of an image and refers to an extremely small fraction of its information content. This paper describes a method for automatically indexing images of individual cells and their associated diagnoses by computationally derived cell descriptors. This methodology may serve to better index data contained in digital image databases, thereby enabling cytologists and pathologists to cross-reference cells of unknown etiology or nature. Design: The indexing method, implemented in a program called PathMaster, uses a series of computer-based feature extraction routines. Descriptors of individual cell characteristics generated by these routines are employed as indexes of cell morphology, texture, color, and spatial orientation. Measurements: The indexing fidelity of the program was tested after populating its database with images of 152 lymphocytes/lymphoma cells captured from lymph node touch preparations stained with hematoxylin and eosin. Images of “unknown” lymphoid cells, previously unprocessed, were then submitted for feature extraction and diagnostic cross-referencing analysis. Results: PathMaster listed the correct diagnosis as its first differential in 94 percent of recognition trials. In the remaining 6 percent of trials, PathMaster listed the correct diagnosis within the first three “differentials.” Conclusion: PathMaster is a pilot cell image indexing program/search engine that creates an indexed reference of images. Use of such a reference may provide assistance in the diagnostic/prognostic process by furnishing a prioritized list of possible identifications for a cell of uncertain etiology. PMID:10887168

  17. PATHS groundwater hydrologic model

    SciTech Connect

    Nelson, R.W.; Schur, J.A.

    1980-04-01

    A preliminary evaluation capability for two-dimensional groundwater pollution problems was developed as part of the Transport Modeling Task for the Waste Isolation Safety Assessment Program (WISAP). Our approach was to use the data limitations as a guide in setting the level of modeling detail. PATHS Groundwater Hydrologic Model is the first level (simplest) idealized hybrid analytical/numerical model for two-dimensional, saturated groundwater flow and single component transport; homogeneous geology. This document consists of the description of the PATHS groundwater hydrologic model. The preliminary evaluation capability prepared for WISAP, including the enhancements that were made because of the authors' experience using the earlier capability is described. Appendixes A through D supplement the report as follows: complete derivations of the background equations are provided in Appendix A. Appendix B is a comprehensive set of instructions for users of PATHS. It is written for users who have little or no experience with computers. Appendix C is for the programmer. It contains information on how input parameters are passed between programs in the system. It also contains program listings and test case listing. Appendix D is a definition of terms.

  18. 'Mighty Eagle' Takes Flight

    NASA Video Gallery

    The "Mighty Eagle," a NASA robotic prototype lander, had a successful first untethered flight Aug. 8 at the Marshall Center. During the 34-second flight, the Mighty Eagle soared and hovered at 30 f...

  19. Autonomous Soaring Flight Results

    NASA Technical Reports Server (NTRS)

    Allen, Michael J.

    2006-01-01

    A viewgraph presentation on autonomous soaring flight results for Unmanned Aerial Vehicles (UAV)'s is shown. The topics include: 1) Background; 2) Thermal Soaring Flight Results; 3) Autonomous Dolphin Soaring; and 4) Future Plans.

  20. Control-oriented reduced order modeling of dipteran flapping flight

    NASA Astrophysics Data System (ADS)

    Faruque, Imraan

    Flying insects achieve flight stabilization and control in a manner that requires only small, specialized neural structures to perform the essential components of sensing and feedback, achieving unparalleled levels of robust aerobatic flight on limited computational resources. An engineering mechanism to replicate these control strategies could provide a dramatic increase in the mobility of small scale aerial robotics, but a formal investigation has not yet yielded tools that both quantitatively and intuitively explain flapping wing flight as an "input-output" relationship. This work uses experimental and simulated measurements of insect flight to create reduced order flight dynamics models. The framework presented here creates models that are relevant for the study of control properties. The work begins with automated measurement of insect wing motions in free flight, which are then used to calculate flight forces via an empirically-derived aerodynamics model. When paired with rigid body dynamics and experimentally measured state feedback, both the bare airframe and closed loop systems may be analyzed using frequency domain system identification. Flight dynamics models describing maneuvering about hover and cruise conditions are presented for example fruit flies (Drosophila melanogaster) and blowflies (Calliphorids). The results show that biologically measured feedback paths are appropriate for flight stabilization and sexual dimorphism is only a minor factor in flight dynamics. A method of ranking kinematic control inputs to maximize maneuverability is also presented, showing that the volume of reachable configurations in state space can be dramatically increased due to appropriate choice of kinematic inputs.

  1. In Flight, Online

    ERIC Educational Resources Information Center

    Lucking, Robert A.; Wighting, Mervyn J.; Christmann, Edwin P.

    2005-01-01

    The concept of flight for human beings has always been closely tied to imagination. To fly like a bird requires a mind that also soars. Therefore, good teachers who want to teach the scientific principles of flight recognize that it is helpful to share stories of their search for the keys to flight. The authors share some of these with the reader,…

  2. Post-Flight Analysis of the Guidance, Navigation, and Control Performance During Orion Exploration Flight Test 1

    NASA Technical Reports Server (NTRS)

    Barth, Andrew; Mamich, Harvey; Hoelscher, Brian

    2015-01-01

    The first test flight of the Orion Multi-Purpose Crew Vehicle presented additional challenges for guidance, navigation and control as compared to a typical re-entry from the International Space Station or other Low Earth Orbit. An elevated re-entry velocity and steeper flight path angle were chosen to achieve aero-thermal flight test objectives. New IMU's, a GPS receiver, and baro altimeters were flight qualified to provide the redundant navigation needed for human space flight. The guidance and control systems must manage the vehicle lift vector in order to deliver the vehicle to a precision, coastal, water landing, while operating within aerodynamic load, reaction control system, and propellant constraints. Extensive pre-flight six degree-of-freedom analysis was performed that showed mission success for the nominal mission as well as in the presence of sensor and effector failures. Post-flight reconstruction analysis of the test flight is presented in this paper to show whether that all performance metrics were met and establish how well the pre-flight analysis predicted the in-flight performance.

  3. Flight testing TECS - The Total Energy Control System

    NASA Technical Reports Server (NTRS)

    Kelly, James R.; Person, Lee H., Jr.; Bruce, Kevin R.

    1986-01-01

    This paper describes some of the unique features of an integrated throttle-elevator control law known as the Total Energy Control System (TECS) which has been flight tested on NASA Langley's Transport Systems Research Vehicle. The TECS concept is designed around total energy principles. It utilizes a full-time autothrottle to control the total energy of the aircraft and the elevator to distribute the energy between speed and flight path objectives. Time histories of selected parameters generated from flight data are used to illustrate the pilot-like control strategy of the system and the priority logic employed when throttle limiting is encountered.

  4. Tracking hurricane paths

    NASA Technical Reports Server (NTRS)

    Prabhakaran, Nagarajan; Rishe, Naphtali; Athauda, Rukshan

    1997-01-01

    The South East coastal region experiences hurricane threat for almost six months in every year. To improve the accuracy of hurricane forecasts, meteorologists would need the storm paths of both the present and the past. A hurricane path can be established if we could identify the correct position of the storm at different times right from its birth to the end. We propose a method based on both spatial and temporal image correlations to locate the position of a storm from satellite images. During the hurricane season, the satellite images of the Atlantic ocean near the equator are examined for the hurricane presence. This is accomplished in two steps. In the first step, only segments with more than a particular value of cloud cover are selected for analysis. Next, we apply image processing algorithms to test the presence of a hurricane eye in the segment. If the eye is found, the coordinate of the eye is recorded along with the time stamp of the segment. If the eye is not found, we examine adjacent segments for the existence of hurricane eye. It is probable that more than one hurricane eye could be found from different segments of the same period. Hence, the above process is repeated till the entire potential area for hurricane birth is exhausted. The subsequent/previous position of each hurricane eye will be searched in the appropriate adjacent segments of the next/previous period to mark the hurricane path. The temporal coherence and spatial coherence of the images are taken into account by our scheme in determining the segments and the associated periods required for analysis.

  5. Critical Path Web Site

    NASA Technical Reports Server (NTRS)

    Robinson, Judith L.; Charles, John B.; Rummel, John A. (Technical Monitor)

    2000-01-01

    Approximately three years ago, the Agency's lead center for the human elements of spaceflight (the Johnson Space Center), along with the National Biomedical Research Institute (NSBRI) (which has the lead role in developing countermeasures) initiated an activity to identify the most critical risks confronting extended human spaceflight. Two salient factors influenced this activity: first, what information is needed to enable a "go/no go" decision to embark on extended human spaceflight missions; and second, what knowledge and capabilities are needed to address known and potential health, safety and performance risks associated with such missions. A unique approach was used to first define and assess those risks, and then to prioritize them. This activity was called the Critical Path Roadmap (CPR) and it represents an opportunity to develop and implement a focused and evolving program of research and technology designed from a "risk reduction" perspective to prevent or minimize the risks to humans exposed to the space environment. The Critical Path Roadmap provides the foundation needed to ensure that human spaceflight, now and in the future, is as safe, productive and healthy as possible (within the constraints imposed on any particular mission) regardless of mission duration or destination. As a tool, the Critical Path Roadmap enables the decisionmaker to select from among the demonstrated or potential risks those that are to be mitigated, and the completeness of that mitigation. The primary audience for the CPR Web Site is the members of the scientific community who are interested in the research and technology efforts required for ensuring safe and productive human spaceflight. They may already be informed about the various space life sciences research programs or they may be newcomers. Providing the CPR content to potential investigators increases the probability of their delivering effective risk mitigations. Others who will use the CPR Web Site and its content

  6. Critical Path Web Site

    NASA Technical Reports Server (NTRS)

    Robinson, Judith L.; Charles, John B.; Rummel, John A. (Technical Monitor)

    2000-01-01

    Approximately three years ago, the Agency's lead center for the human elements of spaceflight (the Johnson Space Center), along with the National Biomedical Research Institute (NSBRI) (which has the lead role in developing countermeasures) initiated an activity to identify the most critical risks confronting extended human spaceflight. Two salient factors influenced this activity: first, what information is needed to enable a "go/no go" decision to embark on extended human spaceflight missions; and second, what knowledge and capabilities are needed to address known and potential health, safety and performance risks associated with such missions. A unique approach was used to first define and assess those risks, and then to prioritize them. This activity was called the Critical Path Roadmap (CPR) and it represents an opportunity to develop and implement a focused and evolving program of research and technology designed from a "risk reduction" perspective to prevent or minimize the risks to humans exposed to the space environment. The Critical Path Roadmap provides the foundation needed to ensure that human spaceflight, now and in the future, is as safe, productive and healthy as possible (within the constraints imposed on any particular mission) regardless of mission duration or destination. As a tool, the Critical Path Roadmap enables the decision maker to select from among the demonstrated or potential risks those that are to be mitigated, and the completeness of that mitigation. The primary audience for the CPR Web Site is the members of the scientific community who are interested in the research and technology efforts required for ensuring safe and productive human spaceflight. They may already be informed about the various space life sciences research programs or they may be newcomers. Providing the CPR content to potential investigators increases the probability of their delivering effective risk mitigations. Others who will use the CPR Web Site and its

  7. Advanced flight software reconfiguraton

    NASA Technical Reports Server (NTRS)

    Porcher, Bryan

    1991-01-01

    Information is given in viewgraph form on advanced flight software reconfiguration. Reconfiguration is defined as identifying mission and configuration specific requirements, controlling mission and configuration specific data, binding this information to the flight software code to perform specific missions, and the release and distribution of the flight software. The objectives are to develop, demonstrate, and validate advanced software reconfiguration tools and techniques; to demonstrate reconfiguration approaches on Space Station Freedom (SSF) onboard systems displays; and to interactively test onboard systems displays, flight software, and flight data.

  8. JAVA PathFinder

    NASA Technical Reports Server (NTRS)

    Mehhtz, Peter

    2005-01-01

    JPF is an explicit state software model checker for Java bytecode. Today, JPF is a swiss army knife for all sort of runtime based verification purposes. This basically means JPF is a Java virtual machine that executes your program not just once (like a normal VM), but theoretically in all possible ways, checking for property violations like deadlocks or unhandled exceptions along all potential execution paths. If it finds an error, JPF reports the whole execution that leads to it. Unlike a normal debugger, JPF keeps track of every step how it got to the defect.

  9. Portage and Path Dependence*

    PubMed Central

    Bleakley, Hoyt; Lin, Jeffrey

    2012-01-01

    We examine portage sites in the U.S. South, Mid-Atlantic, and Midwest, including those on the fall line, a geomorphological feature in the southeastern U.S. marking the final rapids on rivers before the ocean. Historically, waterborne transport of goods required portage around the falls at these points, while some falls provided water power during early industrialization. These factors attracted commerce and manufacturing. Although these original advantages have long since been made obsolete, we document the continuing importance of these portage sites over time. We interpret these results as path dependence and contrast explanations based on sunk costs interacting with decreasing versus increasing returns to scale. PMID:23935217

  10. The Path to NGATS

    NASA Technical Reports Server (NTRS)

    Scardina, John

    2006-01-01

    NGATS operational Improvements and benefits include: 1) Broad area and precision navigation to access and capacity; 2) Airspace access and management to capacity; 3) 4D trajectory based ATM to capacity and efficiency; 4) Reduced separation between aircraft to capacity; 5) Flight deck situational awareness and delegation to capacity and safety; 6) ATM decision support to capacity; 7) Improved weather data and dissemination to capacity and safety; 8) Reduced cost to deliver ATM services to cost; 9) Greatly expanded airport network and improved terminals to capacity.

  11. I-FORCAST: Rapid Flight Planning Tool

    NASA Technical Reports Server (NTRS)

    Oaida, Bogdan; Khan, Mohammed; Mercury, Michael B.

    2012-01-01

    I-FORCAST (Instrument - Field of Regard Coverage Analysis and Simulation Tool) is a flight planning tool specifically designed for quickly verifying the feasibility and estimating the cost of airborne remote sensing campaigns (see figure). Flights are simulated by being broken into three predefined routing algorithms as necessary: mapping in a snaking pattern, mapping the area around a point target (like a volcano) with a star pattern, and mapping the area between a list of points. The tool has been used to plan missions for radar, lidar, and in-situ atmospheric measuring instruments for a variety of aircraft. It has also been used for global and regional scale campaigns and automatically includes landings when refueling is required. The software has been compared to the flight times of known commercial aircraft route travel times, as well as a UAVSAR (Uninhabited Aerial Vehicle Synthetic Aperture Radar) campaign, and was within 15% of the actual flight time. Most of the discrepancy is due to non-optimal flight paths taken by actual aircraft to avoid restricted airspace and used to follow landing and take-off corridors.

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

    NASA Technical Reports Server (NTRS)

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

    1993-01-01

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

  13. Symbology Development for General Aviation Synthetic Vision Primary Flight Displays for the Approach and Missed-Approach Modes of Flight

    NASA Technical Reports Server (NTRS)

    Bartolone, Anthony P.; Hughes, Monica F.; Wong, Douglas T.; Takallu, Mohammad A.

    2004-01-01

    Spatial disorientation induced by inadvertent flight into instrument meteorological conditions (IMC) continues to be a leading cause of fatal accidents in general aviation. The Synthetic Vision Systems General Aviation (SVS-GA) research element, an integral part of NASA s Aviation Safety and Security Program (AvSSP), is investigating a revolutionary display technology designed to mitigate low visibility events such as controlled flight into terrain (CFIT) and low-visibility loss of control (LVLoC). The integrated SVS Primary Flight Display (SVS-PFD) utilizes computer generated 3-dimensional imagery of the surrounding terrain augmented with flight path guidance symbology. This unique combination will provide GA pilots with an accurate representation of their environment and projection of their flight path, regardless of time of day or out-the-window (OTW) visibility. The initial Symbology Development for Head-Down Displays (SD-HDD) simulation experiment examined 16 display configurations on a centrally located high-resolution PFD installed in NASA s General Aviation Work Station (GAWS) flight simulator. The results of the experiment indicate that situation awareness (SA) can be enhanced without having a negative impact on flight technical error (FTE), by providing a general aviation pilot with an integrated SVS display to use when OTW visibility is obscured.

  14. Time-of-flight measurements

    SciTech Connect

    Atwood, W.B.

    1980-10-01

    Time of flight (TOF) measurements are used in high energy particle physics experiments to: (1) distinguish background from events and (2) identify particle types. An example of background separation is shown. These data come from a coincidence electro-production experiment performed at SLAC. The reaction being studied was e + p ..-->.. e' + p' + X where the e(p) stand for an initial and detected electron (proton) and X is a produced but undetected final state with a mass in the rho meson region. The relative time between the detection of an electron and a proton in two of the spectrometers in End Station A is plotted. Data for two different kinematic settings taken in the experiment are shown. The time resolution has been partially corrected for the various flight paths through the instruments and the difference in time resolutions between the two settings results mainly from the incompleteness of this correction. The signal height above the background depends on the time resolution, ..delta.. tau. The chance background is proportional to the product of the electron counting rate, the proton counting rate, and ..delta.. tau. Smaller ..delta.. tau means that higher electron and proton counting rates may be tolerated and result in a similar signal-to-noise ratio.

  15. NASA Dryden Flight Research Center C-17 Research Overview

    NASA Technical Reports Server (NTRS)

    Miller, Chris

    2007-01-01

    A general overview of NASA Dryden Flight Research Center's C-17 Aircraft is presented. The topics include: 1) 2006 Activities PHM Instrumentation Refurbishment; 2) Acoustic and Vibration Sensors; 3) Gas Path Sensors; 4) NASA Instrumentation System Racks; 5) NASA C-17 Simulator; 6) Current Activities; 7) Future Work; 8) Lawn Dart ; 9) Weight Tub; and 10) Parachute Test Vehicle.

  16. Optimal Propellant Maneuver Flight Demonstrations on ISS

    NASA Technical Reports Server (NTRS)

    Bhatt, Sagar; Bedrossian, Nazareth; Longacre, Kenneth; Nguyen, Louis

    2013-01-01

    In this paper, first ever flight demonstrations of Optimal Propellant Maneuver (OPM), a method of propulsive rotational state transition for spacecraft controlled using thrusters, is presented for the International Space Station (ISS). On August 1, 2012, two ISS reorientations of about 180deg each were performed using OPMs. These maneuvers were in preparation for the same-day launch and rendezvous of a Progress vehicle, also a first for ISS visiting vehicles. The first maneuver used 9.7 kg of propellant, whereas the second used 10.2 kg. Identical maneuvers performed without using OPMs would have used approximately 151.1kg and 150.9kg respectively. The OPM method is to use a pre-planned attitude command trajectory to accomplish a rotational state transition. The trajectory is designed to take advantage of the complete nonlinear system dynamics. The trajectory choice directly influences the cost of the maneuver, in this case, propellant. For example, while an eigenaxis maneuver is kinematically the shortest path between two orientations, following that path requires overcoming the nonlinear system dynamics, thereby increasing the cost of the maneuver. The eigenaxis path is used for ISS maneuvers using thrusters. By considering a longer angular path, the path dependence of the system dynamics can be exploited to reduce the cost. The benefits of OPM for the ISS include not only reduced lifetime propellant use, but also reduced loads, erosion, and contamination from thrusters due to fewer firings. Another advantage of the OPM is that it does not require ISS flight software modifications since it is a set of commands tailored to the specific attitude control architecture. The OPM takes advantage of the existing ISS control system architecture for propulsive rotation called USTO control mode1. USTO was originally developed to provide ISS Orbiter stack attitude control capability for a contingency tile-repair scenario, where the Orbiter is maneuvered using its robotic

  17. Path following by a quadrotor using virtual target pursuit guidance

    NASA Astrophysics Data System (ADS)

    Manjunath, Abhishek

    Quadrotors, being more agile than fixed-wing vehicles, are the ideal candidates for autonomous missions in small, compact spaces. The immense challenge to navigate such environments is fulfilled by the concept of path following. Path following is the method of tracking/tracing a fixed, pre-defined path with minimum position error while exerting the lowest possible control effort. In this work, the missile guidance technique of Pure Pursuit is adopted and modified for a 3D quadrotor model to follow fixed, compact trajectories. A specialized hardware testing platform is developed to test this algorithm. The results obtained from simulation and flight tests are compared to results from another technique called Differential Flatness. A small part of this thesis also deals with the stability analysis of the modified 3D Pure Pursuit algorithm to track trajectories expending lower control effort.

  18. A Cockpit Display Designed to Enable Limited Flight Deck Separation Responsibility

    NASA Technical Reports Server (NTRS)

    Johnson, Walter W.; Battiste, Vernol; Bochow, Sheila Holland

    2003-01-01

    Cockpit displays need to be substantially improved to serve the goals of situational awareness, conflict detection, and path replanning, in Free Flight. This paper describes the design of such an advanced cockpit display, along with an initial simulation based usability evaluation. Flight crews were particularly enthusiastic about color coding for relative altitude, dynamically pulsing predictors, and the use of 3-D flight plans for alerting and situational awareness.

  19. 14 CFR 121.493 - Flight time limitations: Flight engineers and flight navigators.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 14 Aeronautics and Space 3 2014-01-01 2014-01-01 false Flight time limitations: Flight engineers and flight navigators. 121.493 Section 121.493 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION... Limitations: Flag Operations § 121.493 Flight time limitations: Flight engineers and flight navigators. (a)...

  20. 14 CFR 121.493 - Flight time limitations: Flight engineers and flight navigators.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 14 Aeronautics and Space 3 2012-01-01 2012-01-01 false Flight time limitations: Flight engineers and flight navigators. 121.493 Section 121.493 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION... Limitations: Flag Operations § 121.493 Flight time limitations: Flight engineers and flight navigators. (a)...

  1. 14 CFR 121.493 - Flight time limitations: Flight engineers and flight navigators.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 14 Aeronautics and Space 3 2013-01-01 2013-01-01 false Flight time limitations: Flight engineers and flight navigators. 121.493 Section 121.493 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION... Limitations: Flag Operations § 121.493 Flight time limitations: Flight engineers and flight navigators. (a)...

  2. 14 CFR 121.493 - Flight time limitations: Flight engineers and flight navigators.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 14 Aeronautics and Space 3 2011-01-01 2011-01-01 false Flight time limitations: Flight engineers and flight navigators. 121.493 Section 121.493 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION... Limitations: Flag Operations § 121.493 Flight time limitations: Flight engineers and flight navigators. (a)...

  3. 14 CFR 121.493 - Flight time limitations: Flight engineers and flight navigators.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 14 Aeronautics and Space 3 2010-01-01 2010-01-01 false Flight time limitations: Flight engineers and flight navigators. 121.493 Section 121.493 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION... Limitations: Flag Operations § 121.493 Flight time limitations: Flight engineers and flight navigators. (a)...

  4. GPS 3-D cockpit displays: Sensors, algorithms, and flight testing

    NASA Astrophysics Data System (ADS)

    Barrows, Andrew Kevin

    Tunnel-in-the-Sky 3-D flight displays have been investigated for several decades as a means of enhancing aircraft safety and utility. However, high costs have prevented commercial development and seriously hindered research into their operational benefits. The rapid development of Differential Global Positioning Systems (DGPS), inexpensive computing power, and ruggedized displays is now changing this situation. A low-cost prototype system was built and flight tested to investigate implementation and operational issues. The display provided an "out the window" 3-D perspective view of the world, letting the pilot see the horizon, runway, and desired flight path even in instrument flight conditions. The flight path was depicted as a tunnel through which the pilot flew the airplane, while predictor symbology provided guidance to minimize path-following errors. Positioning data was supplied, by various DGPS sources including the Stanford Wide Area Augmentation System (WAAS) testbed. A combination of GPS and low-cost inertial sensors provided vehicle heading, pitch, and roll information. Architectural and sensor fusion tradeoffs made during system implementation are discussed. Computational algorithms used to provide guidance on curved paths over the earth geoid are outlined along with display system design issues. It was found that current technology enables low-cost Tunnel-in-the-Sky display systems with a target cost of $20,000 for large-scale commercialization. Extensive testing on Piper Dakota and Beechcraft Queen Air aircraft demonstrated enhanced accuracy and operational flexibility on a variety of complex flight trajectories. These included curved and segmented approaches, traffic patterns flown on instruments, and skywriting by instrument reference. Overlays to existing instrument approaches at airports in California and Alaska were flown and compared with current instrument procedures. These overlays demonstrated improved utility and situational awareness for

  5. Development and Flight Test of an Augmented Thrust-Only Flight Control System on an MD-11 Transport Airplane

    NASA Technical Reports Server (NTRS)

    Burcham, Frank W., Jr.; Maine, Trindel A.; Burken, John J.; Pappas, Drew

    1996-01-01

    An emergency flight control system using only engine thrust, called Propulsion-Controlled Aircraft (PCA), has been developed and flight tested on an MD-11 airplane. In this thrust-only control system, pilot flight path and track commands and aircraft feedback parameters are used to control the throttles. The PCA system was installed on the MD-11 airplane using software modifications to existing computers. Flight test results show that the PCA system can be used to fly to an airport and safely land a transport airplane with an inoperative flight control system. In up-and-away operation, the PCA system served as an acceptable autopilot capable of extended flight over a range of speeds and altitudes. The PCA approaches, go-arounds, and three landings without the use of any non-nal flight controls have been demonstrated, including instrument landing system-coupled hands-off landings. The PCA operation was used to recover from an upset condition. In addition, PCA was tested at altitude with all three hydraulic systems turned off. This paper reviews the principles of throttles-only flight control; describes the MD-11 airplane and systems; and discusses PCA system development, operation, flight testing, and pilot comments.

  6. Multiagent Flight Control in Dynamic Environments with Cooperative Coevolutionary Algorithms

    NASA Technical Reports Server (NTRS)

    Knudson, Matthew D.; Colby, Mitchell; Tumer, Kagan

    2014-01-01

    Dynamic flight environments in which objectives and environmental features change with respect to time pose a difficult problem with regards to planning optimal flight paths. Path planning methods are typically computationally expensive, and are often difficult to implement in real time if system objectives are changed. This computational problem is compounded when multiple agents are present in the system, as the state and action space grows exponentially. In this work, we use cooperative coevolutionary algorithms in order to develop policies which control agent motion in a dynamic multiagent unmanned aerial system environment such that goals and perceptions change, while ensuring safety constraints are not violated. Rather than replanning new paths when the environment changes, we develop a policy which can map the new environmental features to a trajectory for the agent while ensuring safe and reliable operation, while providing 92% of the theoretically optimal performance

  7. 757 Path Loss Measurements

    NASA Technical Reports Server (NTRS)

    Horton, Kent; Huffman, Mitch; Eppic, Brian; White, Harrison

    2005-01-01

    Path Loss Measurements were obtained on three (3) GPS equipped 757 aircraft. Systems measured were Marker Beacon, LOC, VOR, VHF (3), Glide Slope, ATC (2), DME (2), TCAS, and GPS. This data will provide the basis for assessing the EMI (Electromagnetic Interference) safety margins of comm/nav (communication and navigation) systems to portable electronic device emissions. These Portable Electronic Devices (PEDs) include all devices operated in or around the aircraft by crews, passengers, servicing personnel, as well as the general public in the airport terminals. EMI assessment capability is an important step in determining if one system-wide PED EMI policy is appropriate. This data may also be used comparatively with theoretical analysis and computer modeling data sponsored by NASA Langley Research Center and others.

  8. Sequential quadratic programming-based fast path planning algorithm subject to no-fly zone constraints

    NASA Astrophysics Data System (ADS)

    Liu, Wei; Ma, Shunjian; Sun, Mingwei; Yi, Haidong; Wang, Zenghui; Chen, Zengqiang

    2016-08-01

    Path planning plays an important role in aircraft guided systems. Multiple no-fly zones in the flight area make path planning a constrained nonlinear optimization problem. It is necessary to obtain a feasible optimal solution in real time. In this article, the flight path is specified to be composed of alternate line segments and circular arcs, in order to reformulate the problem into a static optimization one in terms of the waypoints. For the commonly used circular and polygonal no-fly zones, geometric conditions are established to determine whether or not the path intersects with them, and these can be readily programmed. Then, the original problem is transformed into a form that can be solved by the sequential quadratic programming method. The solution can be obtained quickly using the Sparse Nonlinear OPTimizer (SNOPT) package. Mathematical simulations are used to verify the effectiveness and rapidity of the proposed algorithm.

  9. Flight code validation simulator

    SciTech Connect

    Sims, B.A.

    1995-08-01

    An End-To-End Simulation capability for software development and validation of missile flight software on the actual embedded computer has been developed utilizing a 486 PC, i860 DSP coprocessor, embedded flight computer and custom dual port memory interface hardware. This system allows real-time interrupt driven embedded flight software development and checkout. The flight software runs in a Sandia Digital Airborne Computer (SANDAC) and reads and writes actual hardware sensor locations in which IMU (Inertial Measurements Unit) data resides. The simulator provides six degree of freedom real-time dynamic simulation, accurate real-time discrete sensor data and acts on commands and discretes from the flight computer. This system was utilized in the development and validation of the successful premier flight of the Digital Miniature Attitude Reference System (DMARS) in January 1995 at the White Sands Missile Range on a two stage attitude controlled sounding rocket.

  10. Flight control actuation system

    NASA Technical Reports Server (NTRS)

    Wingett, Paul T. (Inventor); Gaines, Louie T. (Inventor); Evans, Paul S. (Inventor); Kern, James I. (Inventor)

    2006-01-01

    A flight control actuation system comprises a controller, electromechanical actuator and a pneumatic actuator. During normal operation, only the electromechanical actuator is needed to operate a flight control surface. When the electromechanical actuator load level exceeds 40 amps positive, the controller activates the pneumatic actuator to offset electromechanical actuator loads to assist the manipulation of flight control surfaces. The assistance from the pneumatic load assist actuator enables the use of an electromechanical actuator that is smaller in size and mass, requires less power, needs less cooling processes, achieves high output forces and adapts to electrical current variations. The flight control actuation system is adapted for aircraft, spacecraft, missiles, and other flight vehicles, especially flight vehicles that are large in size and travel at high velocities.

  11. Flight control actuation system

    NASA Technical Reports Server (NTRS)

    Wingett, Paul T. (Inventor); Gaines, Louie T. (Inventor); Evans, Paul S. (Inventor); Kern, James I. (Inventor)

    2004-01-01

    A flight control actuation system comprises a controller, electromechanical actuator and a pneumatic actuator. During normal operation, only the electromechanical actuator is needed to operate a flight control surface. When the electromechanical actuator load level exceeds 40 amps positive, the controller activates the pneumatic actuator to offset electromechanical actuator loads to assist the manipulation of flight control surfaces. The assistance from the pneumatic load assist actuator enables the use of an electromechanical actuator that is smaller in size and mass, requires less power, needs less cooling processes, achieves high output forces and adapts to electrical current variations. The flight control actuation system is adapted for aircraft, spacecraft, missiles, and other flight vehicles, especially flight vehicles that are large in size and travel at high velocities.

  12. Interactive cutting path analysis programs

    NASA Technical Reports Server (NTRS)

    Weiner, J. M.; Williams, D. S.; Colley, S. R.

    1975-01-01

    The operation of numerically controlled machine tools is interactively simulated. Four programs were developed to graphically display the cutting paths for a Monarch lathe, Cintimatic mill, Strippit sheet metal punch, and the wiring path for a Standard wire wrap machine. These programs are run on a IMLAC PDS-ID graphic display system under the DOS-3 disk operating system. The cutting path analysis programs accept input via both paper tape and disk file.

  13. Flight telerobotic servicer

    NASA Technical Reports Server (NTRS)

    Haley, Dennis

    1990-01-01

    Viewgraphs on the Space Station Flight Telerobotic Servicer (SSFTS) are presented. Topics covered include: SSFTS design; SSFTS elements; FTS mission requirements; FTS general requirements; flight telerobotic servicer - telerobot; FTS manipulator; force-torque transducer; end effector changeout mechanism; flight telerobotic servicer - end-of-arm tooling; user interfaces; FTS data management and processing; control subsystem; FTS vision subsystem and camera positioning assembly; FTS workstation display assembly panel; mini-master hand controller; and FTS NASREM system architecture.

  14. Digital flight control research

    NASA Technical Reports Server (NTRS)

    Potter, J. E.; Stern, R. G.; Smith, T. B.; Sinha, P.

    1974-01-01

    The results of studies which were undertaken to contribute to the design of digital flight control systems, particularly for transport aircraft are presented. In addition to the overall design considerations for a digital flight control system, the following topics are discussed in detail: (1) aircraft attitude reference system design, (2) the digital computer configuration, (3) the design of a typical digital autopilot for transport aircraft, and (4) a hybrid flight simulator.

  15. Autonomous Flight Safety System

    NASA Technical Reports Server (NTRS)

    Simpson, James

    2010-01-01

    The Autonomous Flight Safety System (AFSS) is an independent self-contained subsystem mounted onboard a launch vehicle. AFSS has been developed by and is owned by the US Government. Autonomously makes flight termination/destruct decisions using configurable software-based rules implemented on redundant flight processors using data from redundant GPS/IMU navigation sensors. AFSS implements rules determined by the appropriate Range Safety officials.

  16. Unified powered flight guidance

    NASA Technical Reports Server (NTRS)

    Brand, T. J.; Brown, D. W.; Higgins, J. P.

    1973-01-01

    A complete revision of the orbiter powered flight guidance scheme is presented. A unified approach to powered flight guidance was taken to accommodate all phases of exo-atmospheric orbiter powered flight, from ascent through deorbit. The guidance scheme was changed from the previous modified version of the Lambert Aim Point Maneuver Mode used in Apollo to one that employs linear tangent guidance concepts. This document replaces the previous ascent phase equation document.

  17. YF-17 in Flight

    NASA Technical Reports Server (NTRS)

    1976-01-01

    The Northrop Aviation YF-17 technology demonstrator aircraft in flight during a 1976 flight research program at NASA's Dryden Flight Research Center, Edwards, California. From May 27 to July 14, 1976, the Dryden Flight Research Center, Edwards, California, flew the Northrop Aviation YF-17 technology demonstrator to test the high-performance U.S. Air Force fighter at transonic speeds. The objectives of the seven-week flight test program included the study of maneuverability of this aircraft at transonic speeds and the collection of in-flight pressure data from around the afterbody of the aircraft to improve wind-tunnel predictions for future fighter aircraft. Also studied were stability and control and buffeting at high angles of attack as well as handling qualities at high load factors. Another objective of this program was to familiarize center pilots with the operation of advanced high-performance fighter aircraft. During the seven-week program, all seven of the center's test pilots were able to fly the aircraft with Gary Krier serving as project pilot. In general the pilots reported no trouble adapting to the aircraft and reported that it was easy to fly. There were no familiarization flights. All 25 research flights were full-data flights. They obtained data on afterbody pressures, vertical-fin dynamic loads, agility, pilot physiology, and infrared signatures. Average flight time was 45 minutes, although two flights involving in-flight refueling lasted approximately one hour longer than usual. Dryden Project Manager Roy Bryant considered the program a success. Center pilots felt that the aircraft was generations ahead of then current active military aircraft. Originally built for the Air Force's lightweight fighter program, the YF-17 Cobra left Dryden to support the Northrop/Navy F-18 Program. The F-18 Hornet evolved from the YF-17.

  18. Multi-Criteria Path Finding

    NASA Astrophysics Data System (ADS)

    Mohammadi, E.; Hunter, A.

    2012-07-01

    Path finding solutions are becoming a major part of many GIS applications including location based services and web-based GIS services. Most traditional path finding solutions are based on shortest path algorithms that tend to minimize the cost of travel from one point to another. These algorithms make use of some cost criteria that is usually an attribute of the edges in the graph network. Providing one shortest path limits user's flexibility when choosing a possible route, especially when more than one parameter is utilized to calculate cost (e.g., when length, number of traffic lights, and number of turns are used to calculate network cost.) K shortest path solutions tend to overcome this problem by providing second, third, and Kth shortest paths. These algorithms are efficient as long as the graphs edge weight does not change dynamically and no other parameters affect edge weights. In this paper we try to go beyond finding shortest paths based on some cost value, and provide all possible paths disregarding any parameter that may affect total cost. After finding all possible paths, we can rank the results by any parameter or combination of parameters, without a substantial increase in time complexity.

  19. An introduction to critical paths.

    PubMed

    Coffey, Richard J; Richards, Janet S; Remmert, Carl S; LeRoy, Sarah S; Schoville, Rhonda R; Baldwin, Phyllis J

    2005-01-01

    A critical path defines the optimal sequencing and timing of interventions by physicians, nurses, and other staff for a particular diagnosis or procedure. Critical paths are developed through collaborative efforts of physicians, nurses, pharmacists, and others to improve the quality and value of patient care. They are designed to minimize delays and resource utilization and to maximize quality of care. Critical paths have been shown to reduce variation in the care provided, facilitate expected outcomes, reduce delays, reduce length of stay, and improve cost-effectiveness. The approach and goals of critical paths are consistent with those of total quality management (TQM) and can be an important part of an organization's TQM process.

  20. Bat flight: aerodynamics, kinematics and flight morphology.

    PubMed

    Hedenström, Anders; Johansson, L Christoffer

    2015-03-01

    Bats evolved the ability of powered flight more than 50 million years ago. The modern bat is an efficient flyer and recent research on bat flight has revealed many intriguing facts. By using particle image velocimetry to visualize wake vortices, both the magnitude and time-history of aerodynamic forces can be estimated. At most speeds the downstroke generates both lift and thrust, whereas the function of the upstroke changes with forward flight speed. At hovering and slow speed bats use a leading edge vortex to enhance the lift beyond that allowed by steady aerodynamics and an inverted wing during the upstroke to further aid weight support. The bat wing and its skeleton exhibit many features and control mechanisms that are presumed to improve flight performance. Whereas bats appear aerodynamically less efficient than birds when it comes to cruising flight, they have the edge over birds when it comes to manoeuvring. There is a direct relationship between kinematics and the aerodynamic performance, but there is still a lack of knowledge about how (and if) the bat controls the movements and shape (planform and camber) of the wing. Considering the relatively few bat species whose aerodynamic tracks have been characterized, there is scope for new discoveries and a need to study species representing more extreme positions in the bat morphospace.

  1. Automatic layout of integrated-optic time-of-flight circuits

    NASA Astrophysics Data System (ADS)

    Fogg, Ruth D.

    1996-11-01

    This work describes the architecture and algorithms used in the computer-aided design tool developed for the automatic layout of integrated-optic, time-of-flight circuit designs. As in VLSI circuit layout, total wire length and chip area minimization are the goals in the layout of time-of-flight circuits. However, there are two major differences between the layout of time of flight circuits and VLSI circuits. First, the interconnection lengths of time-of-flight designs are exactly specified in order to achieve the necessary delays for signal synchronization. SEcondly, the switching elements are 120 times longer than they are wide. This highly astigmatic aspect ratio causes severe constraints on how and where the switches are placed. Assuming the continued development of corner turning mirrors allows the use of a parallel, row-based device placement architecture and a rectangular, fixed-grid track system for the connecting paths. The layout process proceeds in two steps. The first step involves the use of a partial circuit graph representation to place the elements in rows, oriented in the direction of the signal flow. After iterative improvement of the placement, the second step proceeds with the routing of the connecting paths. The main problem in the automatic layout of time-of-flight circuits is achieving the correct path lengths without overlapping previously routed paths. This problem is solved by taking advantage of a certain degree of variability present in each path, allowing the use of simple heuristics to circumvent previously routed paths.

  2. Flight research and testing

    NASA Technical Reports Server (NTRS)

    Putnam, Terrill W.; Ayers, Theodore G.

    1988-01-01

    Flight research and testing form a critical link in the aeronautic R and D chain. Brilliant concepts, elegant theories, and even sophisticated ground tests of flight vehicles are not sufficient to prove beyond doubt that an unproven aeronautical concept will actually perform as predicted. Flight research and testing provide the ultimate proof that an idea or concept performs as expected. Ever since the Wright brothers, flight research and testing have been the crucible in which aeronautical concepts have advanced and been proven to the point that engineers and companies have been willing to stake their future to produce and design new aircraft. This is still true today, as shown by the development of the experimental X-30 aerospace plane. The Dryden Flight Research Center (Ames-Dryden) continues to be involved in a number of flight research programs that require understanding and characterization of the total airplane in all the aeronautical disciplines, for example the X-29. Other programs such as the F-14 variable-sweep transition flight experiment have focused on a single concept or discipline. Ames-Dryden also continues to conduct flight and ground based experiments to improve and expand the ability to test and evaluate advanced aeronautical concepts. A review of significant aeronautical flight research programs and experiments is presented to illustrate both the progress made and the challenges to come.

  3. Flight research and testing

    NASA Technical Reports Server (NTRS)

    Putnam, Terrill W.; Ayers, Theodore G.

    1989-01-01

    Flight research and testing form a critical link in the aeronautic research and development chain. Brilliant concepts, elegant theories, and even sophisticated ground tests of flight vehicles are not sufficient to prove beyond a doubt that an unproven aeronautical concept will actually perform as predicted. Flight research and testing provide the ultimate proof that an idea or concept performs as expected. Ever since the Wright brothers, flight research and testing were the crucible in which aeronautical concepts were advanced and proven to the point that engineers and companies are willing to stake their future to produce and design aircraft. This is still true today, as shown by the development of the experimental X-30 aerospace plane. The Dryden Flight Research Center (Ames-Dryden) continues to be involved in a number of flight research programs that require understanding and characterization of the total airplane in all the aeronautical disciplines, for example the X-29. Other programs such as the F-14 variable-sweep transition flight experiment have focused on a single concept or discipline. Ames-Dryden also continues to conduct flight and ground based experiments to improve and expand the ability to test and evaluate advanced aeronautical concepts. A review of significant aeronautical flight research programs and experiments is presented to illustrate both the progress being made and the challenges to come.

  4. Alaskan flight trials of a synthetic vision system for instrument landings of a piston twin aircraft

    NASA Astrophysics Data System (ADS)

    Barrows, Andrew K.; Alter, Keith W.; Jennings, Chad W.; Powell, J. D.

    1999-07-01

    Stanford University has developed a low-cost prototype synthetic vision system and flight tested it onboard general aviation aircraft. The display aids pilots by providing an 'out the window' view, making visualization of the desired flight path a simple task. Predictor symbology provides guidance on straight and curved paths presented in a 'tunnel- in-the-sky' format. Based on commodity PC hardware to achieve low cost, the Tunnel Display system uses differential GPS (typically from Stanford prototype Wide Area Augmentation System hardware) for positioning and GPS-aided inertial sensors for attitude determination. The display has been flown onboard Piper Dakota and Beechcraft Queen Air aircraft at several different locations. This paper describes the system, its development, and flight trials culminating with tests in Alaska during the summer of 1998. Operational experience demonstrated the Tunnel Display's ability to increase flight- path following accuracy and situational awareness while easing the task instrument flying.

  5. Technology review of flight crucial flight controls

    NASA Technical Reports Server (NTRS)

    Rediess, H. A.; Buckley, E. C.

    1984-01-01

    The results of a technology survey in flight crucial flight controls conducted as a data base for planning future research and technology programs are provided. Free world countries were surveyed with primary emphasis on the United States and Western Europe because that is where the most advanced technology resides. The survey includes major contemporary systems on operational aircraft, R&D flight programs, advanced aircraft developments, and major research and technology programs. The survey was not intended to be an in-depth treatment of the technology elements, but rather a study of major trends in systems level technology. The information was collected from open literature, personal communications and a tour of several companies, government organizations and research laboratories in the United States, United Kingdom, France, and the Federal Republic of Germany.

  6. Vehicle path-planning in three dimensions using optics analogs for optimizing visibility and energy cost

    NASA Technical Reports Server (NTRS)

    Rowe, Neil C.; Lewis, David H.

    1989-01-01

    Path planning is an important issue for space robotics. Finding safe and energy-efficient paths in the presence of obstacles and other constraints can be complex although important. High-level (large-scale) path planning for robotic vehicles was investigated in three-dimensional space with obstacles, accounting for: (1) energy costs proportional to path length; (2) turn costs where paths change trajectory abruptly; and (3) safety costs for the danger associated with traversing a particular path due to visibility or invisibility from a fixed set of observers. Paths optimal with respect to these cost factors are found. Autonomous or semi-autonomous vehicles were considered operating either in a space environment around satellites and space platforms, or aircraft, spacecraft, or smart missiles operating just above lunar and planetary surfaces. One class of applications concerns minimizing detection, as for example determining the best way to make complex modifications to a satellite without being observed by hostile sensors; another example is verifying there are no paths (holes) through a space defense system. Another class of applications concerns maximizing detection, as finding a good trajectory between mountain ranges of a planet while staying reasonably close to the surface, or finding paths for a flight between two locations that maximize the average number of triangulation points available at any time along the path.

  7. X-43A Flight Controls

    NASA Technical Reports Server (NTRS)

    Baumann, Ethan

    2006-01-01

    A viewgraph presentation detailing X-43A Flight controls at NASA Dryden Flight Research Center is shown. The topics include: 1) NASA Dryden, Overview and current and recent flight test programs; 2) Unmanned Aerial Vehicle Synthetic Aperture Radar (UAVSAR) Program, Program Overview and Platform Precision Autopilot; and 3) Hyper-X Program, Program Overview, X-43A Flight Controls and Flight Results.

  8. Path Analysis: A Brief Introduction.

    ERIC Educational Resources Information Center

    Carducci, Bernardo J.

    Path analysis is presented as a technique that can be used to test on a priori model based on a theoretical conceptualization involving a network of selected variables. This being an introductory source, no previous knowledge of path analysis is assumed, although some understanding of the fundamentals of multiple regression analysis might be…

  9. A Bat Algorithm with Mutation for UCAV Path Planning

    PubMed Central

    Wang, Gaige; Guo, Lihong; Duan, Hong; Liu, Luo; Wang, Heqi

    2012-01-01

    Path planning for uninhabited combat air vehicle (UCAV) is a complicated high dimension optimization problem, which mainly centralizes on optimizing the flight route considering the different kinds of constrains under complicated battle field environments. Original bat algorithm (BA) is used to solve the UCAV path planning problem. Furthermore, a new bat algorithm with mutation (BAM) is proposed to solve the UCAV path planning problem, and a modification is applied to mutate between bats during the process of the new solutions updating. Then, the UCAV can find the safe path by connecting the chosen nodes of the coordinates while avoiding the threat areas and costing minimum fuel. This new approach can accelerate the global convergence speed while preserving the strong robustness of the basic BA. The realization procedure for original BA and this improved metaheuristic approach BAM is also presented. To prove the performance of this proposed metaheuristic method, BAM is compared with BA and other population-based optimization methods, such as ACO, BBO, DE, ES, GA, PBIL, PSO, and SGA. The experiment shows that the proposed approach is more effective and feasible in UCAV path planning than the other models. PMID:23365518

  10. Reconfigurable data path processor

    NASA Technical Reports Server (NTRS)

    Donohoe, Gregory (Inventor)

    2005-01-01

    A reconfigurable data path processor comprises a plurality of independent processing elements. Each of the processing elements advantageously comprising an identical architecture. Each processing element comprises a plurality of data processing means for generating a potential output. Each processor is also capable of through-putting an input as a potential output with little or no processing. Each processing element comprises a conditional multiplexer having a first conditional multiplexer input, a second conditional multiplexer input and a conditional multiplexer output. A first potential output value is transmitted to the first conditional multiplexer input, and a second potential output value is transmitted to the second conditional multiplexer output. The conditional multiplexer couples either the first conditional multiplexer input or the second conditional multiplexer input to the conditional multiplexer output, according to an output control command. The output control command is generated by processing a set of arithmetic status-bits through a logical mask. The conditional multiplexer output is coupled to a first processing element output. A first set of arithmetic bits are generated according to the processing of the first processable value. A second set of arithmetic bits may be generated from a second processing operation. The selection of the arithmetic status-bits is performed by an arithmetic-status bit multiplexer selects the desired set of arithmetic status bits from among the first and second set of arithmetic status bits. The conditional multiplexer evaluates the select arithmetic status bits according to logical mask defining an algorithm for evaluating the arithmetic status bits.

  11. Space Flight. Teacher Resources.

    ERIC Educational Resources Information Center

    2001

    This teacher's guide contains information, lesson plans, and diverse student learning activities focusing on space flight. The guide is divided into seven sections: (1) "Drawing Activities" (Future Flight; Space Fun; Mission: Draw); (2) "Geography" (Space Places); (3) "History" (Space and Time); (4)…

  12. Flight Test Techniques

    DTIC Science & Technology

    2009-07-01

    Fort Rucker, AL 36362-5276 8. PERFORMING ORGANIZATION REPORT NUMBER TOP 7-4-020 9. SPONSORING/ MONITORING AGENCY NAME(S) AND ADDRESS(ES...2 3. REQUIRED TEST CONDITIONS ............................................. 3 3.1...3. REQUIRED TEST CONDITIONS . 3.1 Air Vehicle Flight Test Techniques. Many different flight test techniques are in existence. As technology

  13. Electromechanical flight control actuator

    NASA Technical Reports Server (NTRS)

    1979-01-01

    The feasibility of using an electromechanical actuator (EMA) as the primary flight control equipment in aerospace flight is examined. The EMA motor design is presented utilizing improved permanent magnet materials. The necessary equipment to complete a single channel EMA using the single channel power electronics breadboard is reported. The design and development of an improved rotor position sensor/tachometer is investigated.

  14. Exploring flight crew behaviour

    NASA Technical Reports Server (NTRS)

    Helmreich, R. L.

    1987-01-01

    A programme of research into the determinants of flight crew performance in commercial and military aviation is described, along with limitations and advantages associated with the conduct of research in such settings. Preliminary results indicate significant relationships among personality factors, attitudes regarding flight operations, and crew performance. The potential theoretical and applied utility of the research and directions for further research are discussed.

  15. Java for flight software

    NASA Technical Reports Server (NTRS)

    Benowitz, E.; Niessner, A.

    2003-01-01

    This work involves developing representative mission-critical spacecraft software using the Real-Time Specification for Java (RTSJ). This work currently leverages actual flight software used in the design of actual flight software in the NASA's Deep Space 1 (DSI), which flew in 1998.

  16. NASA Aerospace Flight Battery Systems Program Update

    NASA Technical Reports Server (NTRS)

    Manzo, Michelle; ODonnell, Patricia

    1997-01-01

    The objectives of NASA's Aerospace Flight Battery Systems Program is to: develop, maintain and provide tools for the validation and assessment of aerospace battery technologies; accelerate the readiness of technology advances and provide infusion paths for emerging technologies; provide NASA projects with the required database and validation guidelines for technology selection of hardware and processes relating to aerospace batteries; disseminate validation and assessment tools, quality assurance, reliability, and availability information to the NASA and aerospace battery communities; and ensure that safe, reliable batteries are available for NASA's future missions.

  17. Collabortive Authoring of Walden's Paths

    SciTech Connect

    Li, Yuanling; Bogen II, Paul Logasa; Pogue, Daniel; Furuta, Richard Keith; Shipman, Frank Major

    2012-01-01

    This paper presents a prototype of an authoring tool to allow users to collaboratively build, annotate, manage, share and reuse collections of distributed resources from the World Wide Web. This extends on the Walden’s Path project’s work to help educators bring resources found on the World Wide Web into a linear contextualized structure. The introduction of collaborative authoring feature fosters collaborative learning activities through social interaction among participants, where participants can coauthor paths in groups. Besides, the prototype supports path sharing, branching and reusing; specifically, individual participant can contribute to the group with private collections of knowledge resources; paths completed by group can be shared among group members, such that participants can tailor, extend, reorder and/or replace nodes to have sub versions of shared paths for different information needs.

  18. The Flight Track Noise Impact Model

    NASA Technical Reports Server (NTRS)

    Burn, Melissa; Carey, Jeffrey; Czech, Joseph; Wingrove, Earl R., III

    1997-01-01

    To meet its objective of assisting the U.S. aviation industry with the technological challenges of the future, NASA must identify research areas that have the greatest potential for improving the operation of the air transportation system. To accomplish this, NASA is building an Aviation System Analysis Capability (ASAC). The Flight Track Noise Impact Model (FTNIM) has been developed as part of the ASAC. Its primary purpose is to enable users to examine the impact that quieter aircraft technologies and/or operations might have on air carrier operating efficiency at any one of 8 selected U.S. airports. The analyst selects an airport and case year for study, chooses a set of flight tracks for use in the case, and has the option of reducing the noise of the aircraft by 3, 6, or 10 decibels. Two sets of flight tracks are available for each airport: one that represents actual current conditions, including noise abatement tracks, which avoid flying over noise-sensitive areas; and a second set that offers more efficient routing. FTNIM computes the resultant noise impact and the time and distance saved for each operation on the more efficient, alternate tracks. Noise impact is characterized in three ways: the size of the noise contour footprint, the number of people living within the contours, and the number of homes located in the same contours. Distance and time savings are calculated by comparing the noise abatement flight path length to the more efficient alternate routing.

  19. The flight of Archaeopteryx.

    PubMed

    Chatterjee, Sankar; Templin, R Jack

    2003-01-01

    The origin of avian flight is often equated with the phylogeny, ecology, and flying ability of the primitive Jurassic bird, Archaeopteryx. Debate persists about whether it was a terrestrial cursor or a tree dweller. Despite broad acceptance of its arboreal life style from anatomical, phylogenetic, and ecological evidence, a new version of the cursorial model was proposed recently asserting that a running Archaeopteryx could take off from the ground using thrust and sustain flight in the air. However, Archaeopteryx lacked both the powerful flight muscles and complex wing movements necessary for ground takeoff. Here we describe a flight simulation model, which suggests that for Archaeopteryx, takeoff from a perch would have been more efficient and cost-effective than from the ground. Archaeopteryx may have made short flights between trees, utilizing a novel method of phugoid gliding.

  20. Miscarriage Among Flight Attendants

    PubMed Central

    Grajewski, Barbara; Whelan, Elizabeth A.; Lawson, Christina C.; Hein, Misty J.; Waters, Martha A.; Anderson, Jeri L.; MacDonald, Leslie A.; Mertens, Christopher J.; Tseng, Chih-Yu; Cassinelli, Rick T.; Luo, Lian

    2015-01-01

    Background Cosmic radiation and circadian disruption are potential reproductive hazards for flight attendants. Methods Flight attendants from 3 US airlines in 3 cities were interviewed for pregnancy histories and lifestyle, medical, and occupational covariates. We assessed cosmic radiation and circadian disruption from company records of 2 million individual flights. Using Cox regression models, we compared respondents (1) by levels of flight exposures and (2) to teachers from the same cities, to evaluate whether these exposures were associated with miscarriage. Results Of 2654 women interviewed (2273 flight attendants and 381 teachers), 958 pregnancies among 764 women met study criteria. A hypothetical pregnant flight attendant with median firsttrimester exposures flew 130 hours in 53 flight segments, crossed 34 time zones, and flew 15 hours during her home-base sleep hours (10 pm–8 am), incurring 0.13 mGy absorbed dose (0.36 mSv effective dose) of cosmic radiation. About 2% of flight attendant pregnancies were likely exposed to a solar particle event, but doses varied widely. Analyses suggested that cosmic radiation exposure of 0.1 mGy or more may be associated with increased risk of miscarriage in weeks 9–13 (odds ratio = 1.7 [95% confidence interval = 0.95–3.2]). Risk of a first-trimester miscarriage with 15 hours or more of flying during home-base sleep hours was increased (1.5 [1.1–2.2]), as was risk with high physical job demands (2.5 [1.5–4.2]). Miscarriage risk was not increased among flight attendants compared with teachers. Conclusions Miscarriage was associated with flight attendant work during sleep hours and high physical job demands and may be associated with cosmic radiation exposure. PMID:25563432

  1. Through the eyes of a bird: modelling visually guided obstacle flight

    PubMed Central

    Lin, Huai-Ti; Ros, Ivo G.; Biewener, Andrew A.

    2014-01-01

    Various flight navigation strategies for birds have been identified at the large spatial scales of migratory and homing behaviours. However, relatively little is known about close-range obstacle negotiation through cluttered environments. To examine obstacle flight guidance, we tracked pigeons (Columba livia) flying through an artificial forest of vertical poles. Interestingly, pigeons adjusted their flight path only approximately 1.5 m from the forest entry, suggesting a reactive mode of path planning. Combining flight trajectories with obstacle pole positions, we reconstructed the visual experience of the pigeons throughout obstacle flights. Assuming proportional–derivative control with a constant delay, we searched the relevant parameter space of steering gains and visuomotor delays that best explained the observed steering. We found that a pigeon's steering resembles proportional control driven by the error angle between the flight direction and the desired opening, or gap, between obstacles. Using this pigeon steering controller, we simulated obstacle flights and showed that pigeons do not simply steer to the nearest opening in the direction of flight or destination. Pigeons bias their flight direction towards larger visual gaps when making fast steering decisions. The proposed behavioural modelling method converts the obstacle avoidance behaviour into a (piecewise) target-aiming behaviour, which is better defined and understood. This study demonstrates how such an approach decomposes open-loop free-flight behaviours into components that can be independently evaluated. PMID:24812052

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

    NASA Technical Reports Server (NTRS)

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

    1993-01-01

    The Flight Systems Development branch of the U.S. Army's Avionics Research and Development Activity (AVRADA) and NASA Ames Research Center developed for flight testing a Computer Aided Low-Altitude Helicopter Flight (CALAHF) guidance system. The system includes a trajectory-generation algorithm which uses dynamic programming and a helmet-mounted display (HMD) presentation of a pathway-in-the-sky, a phantom aircraft, and flight-path vector/predictor guidance symbology. The trajectory-generation algorithm uses knowledge of the global mission requirements, a digital terrain map, aircraft performance capabilities, and precision navigation information to determine a trajectory between mission waypoints that seeks valleys to minimize threat exposure. This system was developed and evaluated through extensive use of piloted simulation and has demonstrated a 'pilot centered' concept of automated and integrated navigation and terrain mission planning flight guidance. This system has shown a significant improvement in pilot situational awareness, and mission effectiveness as well as a decrease in training and proficiency time required for a near terrain, nighttime, adverse weather system.

  3. Future Flight Decks

    NASA Technical Reports Server (NTRS)

    Arbuckle, P. Douglas; Abbott, Kathy H.; Abbott, Terence S.; Schutte, Paul C.

    1998-01-01

    The evolution of commercial transport flight deck configurations over the past 20-30 years and expected future developments are described. Key factors in the aviation environment are identified that the authors expect will significantly affect flight deck designers. One of these is the requirement for commercial aviation accident rate reduction, which is probably required if global commercial aviation is to grow as projected. Other factors include the growing incrementalism in flight deck implementation, definition of future airspace operations, and expectations of a future pilot corps that will have grown up with computers. Future flight deck developments are extrapolated from observable factors in the aviation environment, recent research results in the area of pilot-centered flight deck systems, and by considering expected advances in technology that are being driven by other than aviation requirements. The authors hypothesize that revolutionary flight deck configuration changes will be possible with development of human-centered flight deck design methodologies that take full advantage of commercial and/or entertainment-driven technologies.

  4. Initial Flight Test of the Production Support Flight Control Computers at NASA Dryden Flight Research Center

    NASA Technical Reports Server (NTRS)

    Carter, John; Stephenson, Mark

    1999-01-01

    The NASA Dryden Flight Research Center has completed the initial flight test of a modified set of F/A-18 flight control computers that gives the aircraft a research control law capability. The production support flight control computers (PSFCC) provide an increased capability for flight research in the control law, handling qualities, and flight systems areas. The PSFCC feature a research flight control processor that is "piggybacked" onto the baseline F/A-18 flight control system. This research processor allows for pilot selection of research control law operation in flight. To validate flight operation, a replication of a standard F/A-18 control law was programmed into the research processor and flight-tested over a limited envelope. This paper provides a brief description of the system, summarizes the initial flight test of the PSFCC, and describes future experiments for the PSFCC.

  5. Columbia's first shakedown flight

    NASA Astrophysics Data System (ADS)

    Bell, Peter M.

    The space shuttle orbiter Columbia, first of the planned fleet of spacecraft in the nation's space transportation system, will liftoff on its first orbital shakedown flight on or about the 10th of April 1981. Launch will be from the NASA Kennedy Space Center Launch Complex 39A, no earlier than 45 minutes after sunrise. Crew for the first orbital flight will be John W. Young, commander, veteran of two Gemini and two Apollo space flights, and U.S. Navy Capt. Robert L. Crippen, pilot. Crippen has not flown in space.

  6. Intelligent flight control systems

    NASA Technical Reports Server (NTRS)

    Stengel, Robert F.

    1993-01-01

    The capabilities of flight control systems can be enhanced by designing them to emulate functions of natural intelligence. Intelligent control functions fall in three categories. Declarative actions involve decision-making, providing models for system monitoring, goal planning, and system/scenario identification. Procedural actions concern skilled behavior and have parallels in guidance, navigation, and adaptation. Reflexive actions are spontaneous, inner-loop responses for control and estimation. Intelligent flight control systems learn knowledge of the aircraft and its mission and adapt to changes in the flight environment. Cognitive models form an efficient basis for integrating 'outer-loop/inner-loop' control functions and for developing robust parallel-processing algorithms.

  7. Flight Dynamics Analysis Branch

    NASA Technical Reports Server (NTRS)

    Stengle, Tom; Flores-Amaya, Felipe

    2000-01-01

    This report summarizes the major activities and accomplishments carried out by the Flight Dynamics Analysis Branch (FDAB), Code 572, in support of flight projects and technology development initiatives in fiscal year 2000. The report is intended to serve as a summary of the type of support carried out by the FDAB, as well as a concise reference of key accomplishments and mission experience derived from the various mission support roles. The primary focus of the FDAB is to provide expertise in the disciplines of flight dynamics, spacecraft trajectory, attitude analysis, and attitude determination and control. The FDAB currently provides support for missions and technology development projects involving NASA, government, university, and private industry.

  8. Transition Path Theory

    NASA Astrophysics Data System (ADS)

    vanden-Eijnden, E.

    The dynamical behavior of many systems arising in physics, chemistry, biology, etc. is dominated by rare but important transition events between long lived states. For over 70 years, transition state theory (TST) has provided the main theoretical framework for the description of these events [17,33,34]. Yet, while TST and evolutions thereof based on the reactive flux formalism [1, 5] (see also [30,31]) give an accurate estimate of the transition rate of a reaction, at least in principle, the theory tells very little in terms of the mechanism of this reaction. Recent advances, such as transition path sampling (TPS) of Bolhuis, Chandler, Dellago, and Geissler [3, 7] or the action method of Elber [15, 16], may seem to go beyond TST in that respect: these techniques allow indeed to sample the ensemble of reactive trajectories, i.e. the trajectories by which the reaction occurs. And yet, the reactive trajectories may again be rather uninformative about the mechanism of the reaction. This may sound paradoxical at first: what more than actual reactive trajectories could one need to understand a reaction? The problem, however, is that the reactive trajectories by themselves give only a very indirect information about the statistical properties of these trajectories. This is similar to why statistical mechanics is not simply a footnote in books about classical mechanics. What is the probability density that a trajectory be at a given location in state-space conditional on it being reactive? What is the probability current of these reactive trajectories? What is their rate of appearance? These are the questions of interest and they are not easy to answer directly from the ensemble of reactive trajectories. The right framework to tackle these questions also goes beyond standard equilibrium statistical mechanics because of the nontrivial bias that the very definition of the reactive trajectories imply - they must be involved in a reaction. The aim of this chapter is to

  9. Identification of atypical flight patterns

    NASA Technical Reports Server (NTRS)

    Statler, Irving C. (Inventor); Ferryman, Thomas A. (Inventor); Amidan, Brett G. (Inventor); Whitney, Paul D. (Inventor); White, Amanda M. (Inventor); Willse, Alan R. (Inventor); Cooley, Scott K. (Inventor); Jay, Joseph Griffith (Inventor); Lawrence, Robert E. (Inventor); Mosbrucker, Chris (Inventor)

    2005-01-01

    Method and system for analyzing aircraft data, including multiple selected flight parameters for a selected phase of a selected flight, and for determining when the selected phase of the selected flight is atypical, when compared with corresponding data for the same phase for other similar flights. A flight signature is computed using continuous-valued and discrete-valued flight parameters for the selected flight parameters and is optionally compared with a statistical distribution of other observed flight signatures, yielding atypicality scores for the same phase for other similar flights. A cluster analysis is optionally applied to the flight signatures to define an optimal collection of clusters. A level of atypicality for a selected flight is estimated, based upon an index associated with the cluster analysis.

  10. An Introduction to Path Analysis

    ERIC Educational Resources Information Center

    Wolfe, Lee M.

    1977-01-01

    The analytical procedure of path analysis is described in terms of its use in nonexperimental settings in the social sciences. The description assumes a moderate statistical background on the part of the reader. (JKS)

  11. Scattering theory with path integrals

    SciTech Connect

    Rosenfelder, R.

    2014-03-15

    Starting from well-known expressions for the T-matrix and its derivative in standard nonrelativistic potential scattering, I rederive recent path-integral formulations due to Efimov and Barbashov et al. Some new relations follow immediately.

  12. The Effects of Crosswind Flight on Rotor Harmonic Noise Radiation

    NASA Technical Reports Server (NTRS)

    Greenwood, Eric; Sim, Ben W.

    2013-01-01

    In order to develop recommendations for procedures for helicopter source noise characterization, the effects of crosswinds on main rotor harmonic noise radiation are assessed using a model of the Bell 430 helicopter. Crosswinds are found to have a significant effect on Blade-Vortex Interaction (BVI) noise radiation when the helicopter is trimmed with the fuselage oriented along the inertial flight path. However, the magnitude of BVI noise remains unchanged when the pilot orients the fuselage along the aerodynamic velocity vector, crabbing for zero aerodynamic sideslip. The effects of wind gradients on BVI noise are also investigated and found to be smaller in the crosswind direction than in the headwind direction. The effects of crosswinds on lower harmonic noise sources at higher flight speeds are also assessed. In all cases, the directivity of radiated noise is somewhat changed by the crosswind. The model predictions agree well with flight test data for the Bell 430 helicopter captured under various wind conditions. The results of this investigation would suggest that flight paths for future acoustic flight testing are best aligned across the prevailing wind direction to minimize the effects of winds on noise measurements when wind cannot otherwise be avoided.

  13. Controlled Hypersonic Flight Air Data System and Flight Instrumentation

    DTIC Science & Technology

    2007-06-01

    strongly on the flight envelope, re-entry trajectory and vehicle structure. Flight envelope and re-entry trajectory influence primarily the sensor...6 3.3 Flight Wind angles and basic considerations...determination the Mach number independence principle can however be used to derive simple analytic expressions. 3.3 Flight Wind angles and basic

  14. SR-71 Flight

    NASA Video Gallery

    Two SR-71A aircraft were loaned from the U.S. Air Force for use for high-speed, high-altitude research at the NASA Dryden Flight Research Center, Edwards, California. One of them was later returned...

  15. Human Space Flight

    NASA Technical Reports Server (NTRS)

    Woolford, Barbara; Mount, Frances

    2004-01-01

    The first human space flight, in the early 1960s, was aimed primarily at determining whether humans could indeed survive and function in micro-gravity. Would eating and sleeping be possible? What mental and physical tasks could be performed? Subsequent programs increased the complexity of the tasks the crew performed. Table 1 summarizes the history of U.S. space flight, showing the projects, their dates, crew sizes, and mission durations. With over forty years of experience with human space flight, the emphasis now is on how to design space vehicles, habitats, and missions to produce the greatest returns to human knowledge. What are the roles of the humans in space flight in low earth orbit, on the moon, and in exploring Mars?

  16. Beta experiment flight report

    NASA Technical Reports Server (NTRS)

    1982-01-01

    A focused laser Doppler velocimeter system was developed for the measurement of atmospheric backscatter (beta) from aerosols at infrared wavelengths. The system was flight tested at several different locations and the results of these tests are summarized.

  17. Phonotactic flight of the parasitoid fly Emblemasoma auditrix (Diptera: Sarcophagidae).

    PubMed

    Tron, Nanina; Lakes-Harlan, Reinhard

    2017-01-01

    The parasitoid fly Emblemasoma auditrix locates its hosts using acoustic cues from sound producing males of the cicada Okanagana rimosa. Here, we experimentally analysed the flight path of the phonotaxis from a landmark to the target, a hidden loudspeaker in the field. During flight, the fly showed only small lateral deviations. The vertical flight direction angles were initially negative (directed downwards relative to starting position), grew positive (directed upwards) in the second half of the flight, and finally flattened (directed horizontally or slightly upwards), typically resulting in a landing above the loudspeaker. This phonotactic flight pattern was largely independent from sound pressure level or target distance, but depended on the elevation of the sound source. The flight velocity was partially influenced by sound pressure level and distance, but also by elevation. The more elevated the target, the lower was the speed. The accuracy of flight increased with elevation of the target as well as the landing precision. The minimal vertical angle difference eliciting differences in behaviour was 10°. By changing the elevation of the acoustic target after take-off, we showed that the fly is able to orientate acoustically while flying.

  18. Formal language constrained path problems

    SciTech Connect

    Barrett, C.; Jacob, R.; Marathe, M.

    1997-07-08

    In many path finding problems arising in practice, certain patterns of edge/vertex labels in the labeled graph being traversed are allowed/preferred, while others are disallowed. Motivated by such applications as intermodal transportation planning, the authors investigate the complexity of finding feasible paths in a labeled network, where the mode choice for each traveler is specified by a formal language. The main contributions of this paper include the following: (1) the authors show that the problem of finding a shortest path between a source and destination for a traveler whose mode choice is specified as a context free language is solvable efficiently in polynomial time, when the mode choice is specified as a regular language they provide algorithms with improved space and time bounds; (2) in contrast, they show that the problem of finding simple paths between a source and a given destination is NP-hard, even when restricted to very simple regular expressions and/or very simple graphs; (3) for the class of treewidth bounded graphs, they show that (i) the problem of finding a regular language constrained simple path between source and a destination is solvable in polynomial time and (ii) the extension to finding context free language constrained simple paths is NP-complete. Several extensions of these results are presented in the context of finding shortest paths with additional constraints. These results significantly extend the results in [MW95]. As a corollary of the results, they obtain a polynomial time algorithm for the BEST k-SIMILAR PATH problem studied in [SJB97]. The previous best algorithm was given by [SJB97] and takes exponential time in the worst case.

  19. Orion Abort Flight Test

    NASA Technical Reports Server (NTRS)

    Hayes, Peggy Sue

    2010-01-01

    The purpose of NASA's Constellation project is to create the new generation of spacecraft for human flight to the International Space Station in low-earth orbit, the lunar surface, as well as for use in future deep-space exploration. One portion of the Constellation program was the development of the Orion crew exploration vehicle (CEV) to be used in spaceflight. The Orion spacecraft consists of a crew module, service module, space adapter and launch abort system. The crew module was designed to hold as many as six crew members. The Orion crew exploration vehicle is similar in design to the Apollo space capsules, although larger and more massive. The Flight Test Office is the responsible flight test organization for the launch abort system on the Orion crew exploration vehicle. The Flight Test Office originally proposed six tests that would demonstrate the use of the launch abort system. These flight tests were to be performed at the White Sands Missile Range in New Mexico and were similar in nature to the Apollo Little Joe II tests performed in the 1960s. The first flight test of the launch abort system was a pad abort (PA-1), that took place on 6 May 2010 at the White Sands Missile Range in New Mexico. Primary flight test objectives were to demonstrate the capability of the launch abort system to propel the crew module a safe distance away from a launch vehicle during a pad abort, to demonstrate the stability and control characteristics of the vehicle, and to determine the performance of the motors contained within the launch abort system. The focus of the PA-1 flight test was engineering development and data acquisition, not certification. In this presentation, a high level overview of the PA-1 vehicle is given, along with an overview of the Mobile Operations Facility and information on the White Sands tracking sites for radar & optics. Several lessons learned are presented, including detailed information on the lessons learned in the development of wind

  20. Flight evaluation of the terminal guidance system

    NASA Technical Reports Server (NTRS)

    Sandlin, D. R.

    1981-01-01

    The terminal guidance system (TGS) is avionic equipment which gives guidance along a curved descending flight path to a landing. A Cessna 182 was used as the test aircraft and the TGS was installed and connected to the altimeter, DME, RMI, and gyro compass. Approaches were flown by three different pilots. When the aircraft arrives at the termination point, it is set up on final approach for a landing. The TGS provides guidance for curved descending approaches with guideslopes of 6 deg which required, for experienced pilots, workloads that are approximately the same as for an ILS. The glideslope is difficult to track within 1/2 n.m. of the VOR/DME station. The system permits, for experienced pilots, satisfactory approaches with a turn radius as low as 1/2 n.m. and a glideslope of 6 deg. Turn angles have little relation to pilot workload for curved approaches. Pilot experience is a factor for curved approaches. Pilots with low instrument time have difficulty flying steep approaches with small turn radius. Turbulence increases the pilot workload for curved approaches. The TGS does not correct to a given flight path over the ground nor does it adequately compensate for wind drift.

  1. 1999 Flight Mechanics Symposium

    NASA Technical Reports Server (NTRS)

    Lynch, John P. (Editor)

    1999-01-01

    This conference publication includes papers and abstracts presented at the Flight Mechanics Symposium held on May 18-20, 1999. Sponsored by the Guidance, Navigation and Control Center of Goddard Space Flight Center, this symposium featured technical papers on a wide range of issues related to orbit-attitude prediction, determination, and control; attitude sensor calibration; attitude determination error analysis; attitude dynamics; and orbit decay and maneuver strategy. Government, industry, and the academic community participated in the preparation and presentation of these papers.

  2. International Flight Planning Handbook.

    DTIC Science & Technology

    1985-04-01

    SAC pilots and navigators for international operations and provide increased confidence to deal effectively with contingencies that might occur. -, The...control and altitude separation. Therefore, aircrft separation is greater than operations within a radar enviro :..en:. The service is provided by the ICAO...within the CONUS ARTCC system are connected. Therefore, a handoff of a flight will be effected prior to entry into an adjoining FIR or UIR. Once a flight

  3. The flight robotics laboratory

    NASA Technical Reports Server (NTRS)

    Tobbe, Patrick A.; Williamson, Marlin J.; Glaese, John R.

    1988-01-01

    The Flight Robotics Laboratory of the Marshall Space Flight Center is described in detail. This facility, containing an eight degree of freedom manipulator, precision air bearing floor, teleoperated motion base, reconfigurable operator's console, and VAX 11/750 computer system, provides simulation capability to study human/system interactions of remote systems. The facility hardware, software and subsequent integration of these components into a real time man-in-the-loop simulation for the evaluation of spacecraft contact proximity and dynamics are described.

  4. X-29 in flight

    NASA Technical Reports Server (NTRS)

    1991-01-01

    Two X-29 aircraft, featuring one of the most unusual designs in aviation history, were flown at the NASA Ames-Dryden Flight Research Facility (later redesignated the Dryden Flight Research Center), Edwards, Calif., as technology demonstrators to investigate a host of advanced concepts and technologies. This 23 second clip begins with a camera pan from the aircraft's right rear quarter forward as the X-29 flies along in a near- stall maneuver.

  5. Flight behavior of charged droplets in electrohydrodynamic inkjet printing

    NASA Astrophysics Data System (ADS)

    Yudistira, Hadi Teguh; Nguyen, Vu Dat; Dutta, Prashanta; Byun, Doyoung

    2010-01-01

    Flight behaviors of charged droplets are presented for electrohydrodynamic (EHD) inkjet printing. Three different kinds of EHD spraying techniques, pulsed dc, ac, and single potential (SP) ac, have been investigated and both conductive and dielectric target surfaces were considered. Experimental results show that the flight paths of charged droplets may deviate from their regular straight route, i.e., directly from the nozzle to the substrate. Depending on the droplet charge and applied electric field, droplets may deflect, reflect, or retreat to the meniscus. We can solve these drawbacks by SP EHD printing.

  6. Modern digital flight control system design for VTOL aircraft

    NASA Technical Reports Server (NTRS)

    Broussard, J. R.; Berry, P. W.; Stengel, R. F.

    1979-01-01

    Methods for and results from the design and evaluation of a digital flight control system (DFCS) for a CH-47B helicopter are presented. The DFCS employed proportional-integral control logic to provide rapid, precise response to automatic or manual guidance commands while following conventional or spiral-descent approach paths. It contained altitude- and velocity-command modes, and it adapted to varying flight conditions through gain scheduling. Extensive use was made of linear systems analysis techniques. The DFCS was designed, using linear-optimal estimation and control theory, and the effects of gain scheduling are assessed by examination of closed-loop eigenvalues and time responses.

  7. Cassini - Huygens: Heavily instrumented flight systems approaching Saturn and Titan

    NASA Technical Reports Server (NTRS)

    Doody, D.

    2003-01-01

    Abstract?? Cassini and Huygens flight systems are described including capabilities, launch, flight path, mission science objectives, and instruments. Interplanetary cruise, Saturn arrival, and science-tour operations are also discussed, including use of JPL's worldwide Deep Space Network for two-way communications. Launched 15 October 1997, Cassini/Huygens will arrive at the Saturnian system on 1 July 2004. The Cassini Orbiter begins a four-year tour of the ringed gas giant, and the Huygens Probe descends through Titan's dense atmosphere on 14 January 2005.

  8. Meteorological conditions during the summer 1986 CITE 2 flight series

    NASA Technical Reports Server (NTRS)

    Shipham, Mark C.; Cahoon, Donald R.; Bachmeier, A. Scott

    1990-01-01

    An overview of meteorological conditions during the NASA Global Tropospheric Experiment/Chemical Instrumentation Testing and Evaluation (GTE/CITE 2) summer 1986 flight series is presented. Computer-generated isentropic trajectories are used to trace the history of air masses encountered along each aircraft flight path. The synoptic-scale wind fields are depicted based on Montgomery stream function analyses. Time series of aircraft-measured temperature, dew point, ozone, and altitude are shown to depict air mass variability. Observed differences between maritime tropical and maritime polar air masses are discussed.

  9. Magnesium and Space Flight

    PubMed Central

    Smith, Scott M.; Zwart, Sara R.

    2015-01-01

    Magnesium is an essential nutrient for muscle, cardiovascular, and bone health on Earth, and during space flight. We sought to evaluate magnesium status in 43 astronauts (34 male, 9 female; 47 ± 5 years old, mean ± SD) before, during, and after 4–6-month space missions. We also studied individuals participating in a ground analog of space flight (head-down-tilt bed rest; n = 27 (17 male, 10 female), 35 ± 7 years old). We evaluated serum concentration and 24-h urinary excretion of magnesium, along with estimates of tissue magnesium status from sublingual cells. Serum magnesium increased late in flight, while urinary magnesium excretion was higher over the course of 180-day space missions. Urinary magnesium increased during flight but decreased significantly at landing. Neither serum nor urinary magnesium changed during bed rest. For flight and bed rest, significant correlations existed between the area under the curve of serum and urinary magnesium and the change in total body bone mineral content. Tissue magnesium concentration was unchanged after flight and bed rest. Increased excretion of magnesium is likely partially from bone and partially from diet, but importantly, it does not come at the expense of muscle tissue stores. While further study is needed to better understand the implications of these findings for longer space exploration missions, magnesium homeostasis and tissue status seem well maintained during 4–6-month space missions. PMID:26670248

  10. Magnesium and Space Flight.

    PubMed

    Smith, Scott M; Zwart, Sara R

    2015-12-08

    Magnesium is an essential nutrient for muscle, cardiovascular, and bone health on Earth, and during space flight. We sought to evaluate magnesium status in 43 astronauts (34 male, 9 female; 47 ± 5 years old, mean ± SD) before, during, and after 4-6-month space missions. We also studied individuals participating in a ground analog of space flight (head-down-tilt bed rest; n = 27 (17 male, 10 female), 35 ± 7 years old). We evaluated serum concentration and 24-h urinary excretion of magnesium, along with estimates of tissue magnesium status from sublingual cells. Serum magnesium increased late in flight, while urinary magnesium excretion was higher over the course of 180-day space missions. Urinary magnesium increased during flight but decreased significantly at landing. Neither serum nor urinary magnesium changed during bed rest. For flight and bed rest, significant correlations existed between the area under the curve of serum and urinary magnesium and the change in total body bone mineral content. Tissue magnesium concentration was unchanged after flight and bed rest. Increased excretion of magnesium is likely partially from bone and partially from diet, but importantly, it does not come at the expense of muscle tissue stores. While further study is needed to better understand the implications of these findings for longer space exploration missions, magnesium homeostasis and tissue status seem well maintained during 4-6-month space missions.

  11. Designing Flight Deck Procedures

    NASA Technical Reports Server (NTRS)

    Degani, Asaf; Wiener, Earl

    2005-01-01

    Three reports address the design of flight-deck procedures and various aspects of human interaction with cockpit systems that have direct impact on flight safety. One report, On the Typography of Flight- Deck Documentation, discusses basic research about typography and the kind of information needed by designers of flight deck documentation. Flight crews reading poorly designed documentation may easily overlook a crucial item on the checklist. The report surveys and summarizes the available literature regarding the design and typographical aspects of printed material. It focuses on typographical factors such as proper typefaces, character height, use of lower- and upper-case characters, line length, and spacing. Graphical aspects such as layout, color coding, fonts, and character contrast are discussed; and several cockpit conditions such as lighting levels and glare are addressed, as well as usage factors such as angular alignment, paper quality, and colors. Most of the insights and recommendations discussed in this report are transferable to paperless cockpit systems of the future and computer-based procedure displays (e.g., "electronic flight bag") in aerospace systems and similar systems that are used in other industries such as medical, nuclear systems, maritime operations, and military systems.

  12. Implementation of a Novel Flight Tracking and Recovery Package for High Altitude Ballooning Missions

    NASA Astrophysics Data System (ADS)

    Fatima, Aqsa; Nekkanti, Sanjay; Mohan Suri, Ram; Shankar, Divya; Prasad Nagendra, Narayan

    High altitude ballooning is typically used for scientific missions including stratospheric observations, aerological observations, and near space environment technology demonstration. The usage of stratospheric balloons is a cost effective method to pursue several scientific and technological avenues against using satellites in the void of space. Based on the Indian Institute of Astrophysics (IIA) ballooning program for studying Comet ISON using high altitude ballooning, a cost effective flight tracking and recovery package for ballooning missions has been developed using open source hardware. The flight tracking and recovery package is based on using Automatic Packet Reporting System (APRS) and has a redundant Global System for Mobile Communications (GSM) based Global Positioning System (GPS) tracker. The APRS based tracker uses AX.25 protocol for transmission of the GPS coordinates (latitude, longitude, altitude, time) alongside the heading and health parameters of the board (voltage, temperature). APRS uses amateur radio frequencies where data is transmitted in packet messaging format, modulated by radio signals. The receiver uses Very High Frequency (VHF) transceiver to demodulate the APRS signals. The data received will be decoded using MixW (open source software). A bridge will be established between the decoding software and the APRS software. The flight path will be predicted before the launch and the real time position co-ordinates will be used to obtain the real time flight path that will be uploaded online using the bridge connection. We also use open source APRS software to decode and Google Earth to display the real time flight path. Several ballooning campaigns do not employ payload data transmission in real time, which makes the flight tracking and package recovery vital for data collection and recovery of flight instruments. The flight tracking and recovery package implemented in our missions allow independent development of the payload package

  13. Automated ISS Flight Utilities

    NASA Technical Reports Server (NTRS)

    Offermann, Jan Tuzlic

    2016-01-01

    EVADES output. As mentioned above, GEnEVADOSE makes extensive use of ROOT version 6, the data analysis framework developed at the European Organization for Nuclear Research (CERN), and the code is written to the C++11 standard (as are the other projects). My second project is the Automated Mission Reference Exposure Utility (AMREU).Unlike GEnEVADOSE, AMREU is a combination of three frameworks written in both Python and C++, also making use of ROOT (and PyROOT). Run as a combination of daily and weekly cron jobs, these macros query the SRAG database system to determine the active ISS missions, and query minute-by-minute radiation dose information from ISS-TEPC (Tissue Equivalent Proportional Counter), one of the radiation detectors onboard the ISS. Using this information, AMREU creates a corrected data set of daily radiation doses, addressing situations where TEPC may be offline or locked up by correcting doses for days with less than 95% live time (the total amount time the instrument acquires data) by averaging the past 7 days. As not all errors may be automatically detectable, AMREU also allows for manual corrections, checking an updated plaintext file each time it runs. With the corrected data, AMREU generates cumulative dose plots for each mission, and uses a Python script to generate a flight note file (.docx format) containing these plots, as well as information sections to be filled in and modified by the space weather environment officers with information specific to the week. AMREU is set up to run without requiring any user input, and it automatically archives old flight notes and information files for missions that are no longer active. My other projects involve cleaning up a large data set from the Charged Particle Directional Spectrometer (CPDS), joining together many different data sets in order to clean up information in SRAG SQL databases, and developing other automated utilities for displaying information on active solar regions, that may be used by the

  14. X-Hab Challenge: Students in the Critical Path

    NASA Technical Reports Server (NTRS)

    Howe, A. Scott; Drew, B. A.; Bailey, L.; Gill, T.; Liolios, S.; Walsh, E.; Dory, J.; Howe, A. S.; Smitherman, D.; Bookout, P.; Howard, Robert; Tri, T.; Toups, Larry

    2012-01-01

    The eXploration Habitat (X-Hab) Academic Innovation Challenge follows a non-typical format for university student competitions. Rather than provide a realistic simulated mission for the students to perform, the X-Hab Challenge puts the student teams in the critical path of NASA's human space flight Exploration systems research and development, and expects them to deliver a product that will likely become heritage for eventual flight systems in the years to come. The added responsibility has two major benefits: the university teams are given real ownership in the NASA vision; students are given Principal Investigator (PI) status for their contribution and are looked upon as peers in the development process. This paper introduces the X-Hab Challenge and discusses the successes behind the program.

  15. Systems Engineering Technical Authority: A Path to Mission Success

    NASA Technical Reports Server (NTRS)

    Andary, James F.; So, Maria M.; Breindel, Barry

    2008-01-01

    The systems engineering of space missions to study planet Earth has been an important focus of the National Aeronautics and Space Administration (NASA) since its inception. But all space missions are becoming increasingly complex and this fact, reinforced by some major mishaps, has caused NASA to reevaluate their approach to achieving safety and mission success. A new approach ensures that there are adequate checks and balances in place to maximize the probability of safety and mission success. To this end the agency created the concept of Technical Authority which identifies a key individual accountable and responsible for the technical integrity of a flight mission as well as a project-independent reporting path. At the Goddard Space Flight Center (GSFC) this responsibility ultimately begins with the Mission Systems Engineer (MSE) for each satellite mission. This paper discusses the Technical Authority process and then describes some unique steps that are being taken at the GSFC to support these MSEs in meeting their responsibilities.

  16. 14 CFR 121.414 - Initial and transition training and checking requirements: flight instructors (airplane), flight...

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ....414 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED... flight training for flight instructors (airplane), flight engineer instructors (airplane), and flight... to develop during instruction. (4) For flight engineer instructors (airplane) and flight...

  17. 14 CFR 121.414 - Initial and transition training and checking requirements: flight instructors (airplane), flight...

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ....414 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED... flight training for flight instructors (airplane), flight engineer instructors (airplane), and flight... to develop during instruction. (4) For flight engineer instructors (airplane) and flight...

  18. 14 CFR 121.414 - Initial and transition training and checking requirements: flight instructors (airplane), flight...

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ....414 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED... flight training for flight instructors (airplane), flight engineer instructors (airplane), and flight... to develop during instruction. (4) For flight engineer instructors (airplane) and flight...

  19. Path planning and Ground Control Station simulator for UAV

    NASA Astrophysics Data System (ADS)

    Ajami, A.; Balmat, J.; Gauthier, J.-P.; Maillot, T.

    In this paper we present a Universal and Interoperable Ground Control Station (UIGCS) simulator for fixed and rotary wing Unmanned Aerial Vehicles (UAVs), and all types of payloads. One of the major constraints is to operate and manage multiple legacy and future UAVs, taking into account the compliance with NATO Combined/Joint Services Operational Environment (STANAG 4586). Another purpose of the station is to assign the UAV a certain degree of autonomy, via autonomous planification/replanification strategies. The paper is organized as follows. In Section 2, we describe the non-linear models of the fixed and rotary wing UAVs that we use in the simulator. In Section 3, we describe the simulator architecture, which is based upon interacting modules programmed independently. This simulator is linked with an open source flight simulator, to simulate the video flow and the moving target in 3D. To conclude this part, we tackle briefly the problem of the Matlab/Simulink software connection (used to model the UAV's dynamic) with the simulation of the virtual environment. Section 5 deals with the control module of a flight path of the UAV. The control system is divided into four distinct hierarchical layers: flight path, navigation controller, autopilot and flight control surfaces controller. In the Section 6, we focus on the trajectory planification/replanification question for fixed wing UAV. Indeed, one of the goals of this work is to increase the autonomy of the UAV. We propose two types of algorithms, based upon 1) the methods of the tangent and 2) an original Lyapunov-type method. These algorithms allow either to join a fixed pattern or to track a moving target. Finally, Section 7 presents simulation results obtained on our simulator, concerning a rather complicated scenario of mission.

  20. Antimicrobial Medication Stability During Space Flight

    NASA Technical Reports Server (NTRS)

    Putcha, Lakshmi; Berens, Kurt; Du, Jianping

    2004-01-01

    The current vision for manned space flight involves lunar and Martian exploration within the next two decades. In order for NASA to achieve these goals, a significant amount of preparation is necessary to assure crew health and safety. A mission critical component of this vision centers around the stability of pharmaceutical preparations contained in the space medicine kits. Evidence suggests that even brief periods of space flight have significant detrimental effects for some pharmaceutical formulations. The effects observed include decreases in physical stability of drug formulations of sufficient magnitude to effect bioavailability. Other formulations exhibit decreases in chemical stability resulting in a loss of potency. Physical or-chemical instability of pharmaceutical formulations i n space medicine kits could render the products ineffective. Of additional concern is the potential for formation of toxic degradation products as a result of the observed product instability. This proposal addresses Question number 11 of Clinical Capabilities in the Critical Path Roadmap. In addition, this proposal will reduce the risks and/or enhance the capabilities of humans exposed to the environments of space flight or an extraterrestrial destination by identifying drugs that may be unstable during spaceflight.

  1. History of nutrition in space flight: overview.

    PubMed

    Lane, Helen W; Feeback, Daniel L

    2002-10-01

    Major accomplishments in nutritional sciences for support of human space travel have occurred over the past 40 y. This article reviews these accomplishments, beginning with the early Gemini program and continuing through the impressive results from the first space station Skylab program that focused on life sciences research, the Russian contributions through the Mir space station, the US Shuttle life sciences research, and the emerging International Space Station missions. Nutrition is affected by environmental conditions such as radiation, temperature, and atmospheric pressures, and these are reviewed. Nutrition with respect to space flight is closely interconnected with other life sciences research disciplines including the study of hematology, immunology, as well as neurosensory, cardiovascular, gastrointestinal, circadian rhythms, and musculoskeletal physiology. These relationships are reviewed in reference to the overall history of nutritional science in human space flight. Cumulative nutritional research over the past four decades has resulted in the current nutritional requirements for astronauts. Space-flight nutritional recommendations are presented along with the critical path road map that outlines the research needed for future development of nutritional requirements.

  2. History of nutrition in space flight: overview

    NASA Technical Reports Server (NTRS)

    Lane, Helen W.; Feeback, Daniel L.

    2002-01-01

    Major accomplishments in nutritional sciences for support of human space travel have occurred over the past 40 y. This article reviews these accomplishments, beginning with the early Gemini program and continuing through the impressive results from the first space station Skylab program that focused on life sciences research, the Russian contributions through the Mir space station, the US Shuttle life sciences research, and the emerging International Space Station missions. Nutrition is affected by environmental conditions such as radiation, temperature, and atmospheric pressures, and these are reviewed. Nutrition with respect to space flight is closely interconnected with other life sciences research disciplines including the study of hematology, immunology, as well as neurosensory, cardiovascular, gastrointestinal, circadian rhythms, and musculoskeletal physiology. These relationships are reviewed in reference to the overall history of nutritional science in human space flight. Cumulative nutritional research over the past four decades has resulted in the current nutritional requirements for astronauts. Space-flight nutritional recommendations are presented along with the critical path road map that outlines the research needed for future development of nutritional requirements.

  3. Flight Planning in the Cloud

    NASA Technical Reports Server (NTRS)

    Flores, Sarah L.; Chapman, Bruce D.; Tung, Waye W.; Zheng, Yang

    2011-01-01

    This new interface will enable Principal Investigators (PIs), as well as UAVSAR (Uninhabited Aerial Vehicle Synthetic Aperture Radar) members to do their own flight planning and time estimation without having to request flight lines through the science coordinator. It uses an all-in-one Google Maps interface, a JPL hosted database, and PI flight requirements to design an airborne flight plan. The application will enable users to see their own flight plan being constructed interactively through a map interface, and then the flight planning software will generate all the files necessary for the flight. Afterward, the UAVSAR team can then complete the flight request, including calendaring and supplying requisite flight request files in the expected format for processing by NASA s airborne science program. Some of the main features of the interface include drawing flight lines on the map, nudging them, adding them to the current flight plan, and reordering them. The user can also search and select takeoff, landing, and intermediate airports. As the flight plan is constructed, all of its components are constantly being saved to the database, and the estimated flight times are updated. Another feature is the ability to import flight lines from previously saved flight plans. One of the main motivations was to make this Web application as simple and intuitive as possible, while also being dynamic and robust. This Web application can easily be extended to support other airborne instruments.

  4. Flight Simulator Evaluation of Synthetic Vision Display Concepts to Prevent Controlled Flight Into Terrain (CFIT)

    NASA Technical Reports Server (NTRS)

    Arthur, Jarvis J., III; Prinzel, Lawrence J., III; Kramer, Lynda J.; Parrish, Russell V.; Bailey, Randall E.

    2004-01-01

    In commercial aviation, over 30-percent of all fatal accidents worldwide are categorized as Controlled Flight Into Terrain (CFIT) accidents, where a fully functioning airplane is inadvertently flown into the ground. The major hypothesis for a simulation experiment conducted at NASA Langley Research Center was that a Primary Flight Display (PFD) with synthetic terrain will improve pilots ability to detect and avoid potential CFITs compared to conventional instrumentation. All display conditions, including the baseline, contained a Terrain Awareness and Warning System (TAWS) and Vertical Situation Display (VSD) enhanced Navigation Display (ND). Each pilot flew twenty-two approach departure maneuvers in Instrument Meteorological Conditions (IMC) to the terrain challenged Eagle County Regional Airport (EGE) in Colorado. For the final run, flight guidance cues were altered such that the departure path went into terrain. All pilots with a synthetic vision system (SVS) PFD (twelve of sixteen pilots) noticed and avoided the potential CFIT situation. The four pilots who flew the anomaly with the conventional baseline PFD configuration (which included a TAWS and VSD enhanced ND) had a CFIT event. Additionally, all the SVS display concepts enhanced the pilot s situational awareness, decreased workload and improved flight technical error (FTE) compared to the baseline configuration.

  5. Long duration flights management

    NASA Astrophysics Data System (ADS)

    Sosa-Sesma, Sergio; Letrenne, Gérard; Spel, Martin; Charbonnier, Jean-Marc

    Long duration flights (LDF) require a special management to take the best decisions in terms of ballast consumption and instant of separation. As a contrast to short duration flights, where meteorological conditions are relatively well known, for LDF we need to include the meteorological model accuracy in trajectory simulations. Dispersions on the fields of model (wind, temperature and IR fluxes) could make the mission incompatible with safety rules, authorized zones and others flight requirements. Last CNES developments for LDF act on three main axes: 1. Although ECMWF-NCEP forecast allows generating simulations from a 4D point (altitude, latitude, longitude and UT time), result is not statistical, it is determinist. To take into account model dispersion a meteorological NCEP data base was analyzed. A comparison between Analysis (AN) and Forecast (FC) for the same time frame had been done. Result obtained from this work allows implementing wind and temperature dispersions on balloon flight simulator. 2. For IR fluxes, NCEP does not provide ascending IR fluxes in AN mode but only in FC mode. To obtain the IR fluxes for each time frame, satellite images are used. A comparison between FC and satellites measurements had been done. Results obtained from this work allow implementing flux dispersions on balloon flight simulator. 3. An improved cartography containing a vast data base had been included in balloon flight simulator. Mixing these three points with balloon flight dynamics we have obtained two new tools for observing balloon evolution and risk, one of them is called ASTERISK (Statistic Tool for Evaluation of Risk) for calculations and the other one is called OBERISK (Observing Balloon Evolution and Risk) for visualization. Depending on the balloon type (super pressure, zero pressure or MIR) relevant information for the flight manager is different. The goal is to take the best decision according to the global situation to obtain the largest flight duration with

  6. XV-15 in flight

    NASA Technical Reports Server (NTRS)

    1981-01-01

    The XV-15 Tilt-Rotor aircraft was designed by Bell Aircraft, Niagara Falls, New York, in the mid-1970's under a contract with NASA and the U.S. Army. It was capable of taking off and landing vertically like a helicopter and of flying horizontally when its 'prop rotors' were rotated forward and downward. NASA Ames Research Center, Mountain View, California, and the Army Air Mobility Laboratory cooperated in a program to obtain two of the aircraft for flight research. The first aircraft arrived at Ames on March 23, 1978. After wind-tunnel testing in the Ames 40-by-80-foot wind tunnel, the aircraft began its contractor flight tests at Ames on April 23, 1979. Bell, Army, and U.S. Marine pilots flew it on 140 separate missions over the next year before turning the aircraft over to Ames. That center, in turn, chose to perform the initial flight research at the Dryden Flight Research Center, Edwards, California, where aircraft Number 2 began flight research with Dryden pilots on October 3, 1980, followed by aircraft Number 1 (previously the wind-tunnel model) the following year. Service pilots continued to fly the aircraft, including missions at Fort Huachuca, Arizona, and aboard the Navy USS Tripoli. Ames pilots also flew the XV-15 extensively during its lengthy period of flight research. The Ames flight research team finally returned aircraft Number 2 to Bell Helicopter in April 1994. The successful flight research with the XV-15, spearheaded by the team at Ames, led to the military V-22 Osprey and to the possibility of using tilt-rotor aircraft as a solution to the problem of crowded airports and highways. The XV-15 weighed 9,076 pounds empty and measured slightly more than 46 feet in length. The distance from the ground to the top of the tail was nearly 13 feet, and the span of its forward-swept wings was about 32 feet. It featured two three-bladed rotors, each measuring 25 feet in diameter. This movie clip runs about 49 seconds showing the XV-15 aircraft turning and

  7. Eclipse takeoff and flight

    NASA Technical Reports Server (NTRS)

    1998-01-01

    This 25-second clip shows the QF-106 'Delta Dart' tethered to the USAF C-141A during takeoff and in flight. NASA Dryden Flight Research Center, Edwards, California, supported a Kelly Space and Technology, Inc. (KST)/U.S. Air Force project known as Eclipse, which demonstrated a reusable tow launch vehicle concept. The purpose of the project was to demonstrate a reusable tow launch vehicle concept that had been conceived and patented by KST. Kelly Space obtained a contract with the USAF Research Laboratory for the tow launch demonstration project under the Small Business Innovation Research (SBIR) program. The USAF SBIR contract included the modifications to turn the QF-106 into the Experimental Demonstrator #1 (EXD-01), and the C141A aircraft to incorporate the tow provisions to link the two aircraft, as well as conducting flight tests. The demonstration consisted of ground and flight tests. These tests included a Combined Systems Test of both airplanes joined by a tow rope, a towed taxi test, and six towed flights. The primary goal of the project was demonstrating the tow phase of the Eclipse concept using a scaled-down tow aircraft (C-141A) and a representative aerodynamically-shaped aircraft (QF-106A) as a launch vehicle. This was successfully accomplished. On December 20, 1997, NASA research pilot Mark Stucky flew a QF-106 on the first towed flight behind an Air Force C-141 in the joint Eclipse project with KST to demonstrate the reusable tow launch vehicle concept developed by KST. Kelly hoped to use the data from the tow tests to validate a tow-to-launch procedure for reusable space launch vehicles. Stucky flew six successful tow tests between December 1997 and February 6, 1998. On February 6, 1998, the sixth and final towed flight brought the project to a successful completion. Preliminary flight results determined that the handling qualities of the QF-106 on tow were very stable; actual flight measured values of tow rope tension were well within predictions

  8. Perseus Post-flight

    NASA Technical Reports Server (NTRS)

    1991-01-01

    Crew members check out the Perseus proof-of-concept vehicle on Rogers Dry Lake, adjacent to the Dryden Flight Research Center, Edwards, California, after a test flight in 1991. Perseus B is a remotely piloted aircraft developed as a design-performance testbed under NASA's Environmental Research Aircraft and Sensor Technology (ERAST) project. Perseus is one of several flight vehicles involved in the ERAST project. A piston engine, propeller-powered aircraft, Perseus was designed and built by Aurora Flight Sciences Corporation, Manassas, Virginia. The objectives of Perseus B's ERAST flight tests have been to reach and maintain horizontal flight above altitudes of 60,000 feet and demonstrate the capability to fly missions lasting from 8 to 24 hours, depending on payload and altitude requirements. The Perseus B aircraft established an unofficial altitude record for a single-engine, propeller-driven, remotely piloted aircraft on June 27, 1998. It reached an altitude of 60,280 feet. In 1999, several modifications were made to the Perseus aircraft including engine, avionics, and flight-control-system improvements. These improvements were evaluated in a series of operational readiness and test missions at the Dryden Flight Research Center, Edwards, California. Perseus is a high-wing monoplane with a conventional tail design. Its narrow, straight, high-aspect-ratio wing is mounted atop the fuselage. The aircraft is pusher-designed with the propeller mounted in the rear. This design allows for interchangeable scientific-instrument payloads to be placed in the forward fuselage. The design also allows for unobstructed airflow to the sensors and other devices mounted in the payload compartment. The Perseus B that underwent test and development in 1999 was the third generation of the Perseus design, which began with the Perseus Proof-Of-Concept aircraft. Perseus was initially developed as part of NASA's Small High-Altitude Science Aircraft (SHASA) program, which later evolved

  9. Perseus in Flight

    NASA Technical Reports Server (NTRS)

    1991-01-01

    The Perseus proof-of-concept vehicle in flight at the Dryden Flight Research Center, Edwards, California in 1991. Perseus is one of several remotely-piloted aircraft designed for high-altitude, long-endurance scientific sampling missions being evaluated under the ERAST program. Perseus B is a remotely piloted aircraft developed as a design-performance testbed under NASA's Environmental Research Aircraft and Sensor Technology (ERAST) project. Perseus is one of several flight vehicles involved in the ERAST project. A piston engine, propeller-powered aircraft, Perseus was designed and built by Aurora Flight Sciences Corporation, Manassas, Virginia. The objectives of Perseus B's ERAST flight tests have been to reach and maintain horizontal flight above altitudes of 60,000 feet and demonstrate the capability to fly missions lasting from 8 to 24 hours, depending on payload and altitude requirements. The Perseus B aircraft established an unofficial altitude record for a single-engine, propeller-driven, remotely piloted aircraft on June 27, 1998. It reached an altitude of 60,280 feet. In 1999, several modifications were made to the Perseus aircraft including engine, avionics, and flight-control-system improvements. These improvements were evaluated in a series of operational readiness and test missions at the Dryden Flight Research Center, Edwards, California. Perseus is a high-wing monoplane with a conventional tail design. Its narrow, straight, high-aspect-ratio wing is mounted atop the fuselage. The aircraft is pusher-designed with the propeller mounted in the rear. This design allows for interchangeable scientific-instrument payloads to be placed in the forward fuselage. The design also allows for unobstructed airflow to the sensors and other devices mounted in the payload compartment. The Perseus B that underwent test and development in 1999 was the third generation of the Perseus design, which began with the Perseus Proof-Of-Concept aircraft. Perseus was initially

  10. Aerodynamics of bird flight

    NASA Astrophysics Data System (ADS)

    Dvořák, Rudolf

    2016-03-01

    Unlike airplanes birds must have either flapping or oscillating wings (the hummingbird). Only such wings can produce both lift and thrust - two sine qua non attributes of flying.The bird wings have several possibilities how to obtain the same functions as airplane wings. All are realized by the system of flight feathers. Birds have also the capabilities of adjusting the shape of the wing according to what the immediate flight situation demands, as well as of responding almost immediately to conditions the flow environment dictates, such as wind gusts, object avoidance, target tracking, etc. In bird aerodynamics also the tail plays an important role. To fly, wings impart downward momentum to the surrounding air and obtain lift by reaction. How this is achieved under various flight situations (cruise flight, hovering, landing, etc.), and what the role is of the wing-generated vortices in producing lift and thrust is discussed.The issue of studying bird flight experimentally from in vivo or in vitro experiments is also briefly discussed.

  11. KELVIN rare gas time-of-flight program

    SciTech Connect

    Vernon, M.

    1981-03-01

    The purpose of this appendix is to explain in detail the procedure for performing time-of-flight (TOF) calibration measurements. The result of the calibration measurements is to assign a correct length (L) to the path the molecules travel in a particular experimental configuration. In conjunction with time information (t) a velocity distribution (L/t) can then be determined. The program KELVIN is listed.

  12. Ellisoidal mirror for time-of-flight electron energy analysis

    SciTech Connect

    Waligorski, G.; Cooke, W.E.

    1993-05-01

    We have constructed an ellipsoidal electron mirror from a pair of molded stainless steel grids in a fashion similar to the parabolic mirror constructed by Trevor et al.. The ellipsoidal geometry provides superior collection efficiency while maintaining good temporal resolution for our small flight path of 19 cm. We will present data showing the use of this analyzer to separate electrons produced in various channels following the decay of doubly-excited autoionizing states of barium.

  13. An in flight investigation of pitch rate flight control systems and application of frequency domain and time domain predictive criteria

    NASA Technical Reports Server (NTRS)

    Berthe, C. J.; Chalk, C. R.; Sarrafian, S.

    1984-01-01

    The degree of attitude control provided by current integral-proportional pitch rate command-type control systems, while a prerequisite for flared landing, is insufficient for 'Level 1' performance. The pilot requires 'surrogate' feedback cues to precisely control flight path in the landing flare. Monotonic stick forces and pilot station vertical acceleration are important cues which can be provided by means of angle-of-attack and pitch rate feedback in order to achieve conventional short period and phugoid characteristics. Integral-proportional pitch rate flight control systems can be upgraded to Level 1 flared landing performance by means of lead/lag and washout prefilters in the command path. Strong pilot station vertical acceleration cues can provide Level 1 flared landing performance even in the absence of monotonic stick forces.

  14. X-31 in flight - Post Stall Maneuver

    NASA Technical Reports Server (NTRS)

    1995-01-01

    Two X-31 Enhanced Fighter Maneuverability (EFM) demonstrators were flown at the Rockwell International facility, Palmdale, California, and the NASA Dryden Flight Research Center, Edwards, California, to obtain data that may apply to the design of highly-maneuverable next-generation fighters. The program had its first flight on October 11, 1990, in Palmdale; it ended in June 1995. The X-31 program demonstrated the value of thrust vectoring (directing engine exhaust flow) coupled with advanced flight control systems, to provide controlled flight during close-in air combat at very high angles of attack. The result of this increased maneuverability is an aircraft with a significant advantage over conventional fighters. 'Angle-of-attack' (alpha) is an engineering term to describe the angle of an aircraft body and wings relative to its actual flight path. During maneuvers, pilots often fly at extreme angles of attack -- with the nose pitched up while the aircraft continues in its original direction. This can lead to loss of control and result in the loss of the aircraft, pilot or both. Three thrust vectoring paddles made of graphite epoxy mounted on the exhaust nozzle of the X-31 aircraft directed the exhaust flow to provide control in pitch (up and down) and yaw (right and left) to improve control. The paddles can sustain heat of up to 1,500 degrees centigrade for extended periods of time. In addition the X-31 aircraft were configured with movable forward canards and fixed aft strakes. The canards were small wing-like structures set on the wing line between the nose and the leading edge of the wing. The strakes were set on the same line between the trailing edge of the wing and the engine exhaust. Both supplied additional control in tight maneuvering situations. The X-31 research program produced technical data at high angles of attack. This information is giving engineers and aircraft designers a better understanding of aerodynamics, effectiveness of flight controls

  15. X-31 in flight, Herbst maneuver

    NASA Technical Reports Server (NTRS)

    1990-01-01

    Two X-31 Enhanced Fighter Maneuverability (EFM) demonstrators were flown at the Rockwell International Palmdale, California, facility and the NASA Dryden Flight Research Center, Edwards, California, to obtain data that may apply to the design of highly-maneuverable next-generation fighters. The program had its first flight on October 11, 1990, in Palmdale; it ended in June 1995. The X-31 program demonstrated the value of thrust vectoring (directing engine exhaust flow) coupled with advanced flight control systems, to provide controlled flight during close-in air combat at very high angles of attack. The result of this increased maneuverability is an aircraft with a significant advantage over conventional fighters. 'Angle-of-attack' (alpha) is an engineering term to describe the angle of an aircraft body and wings relative to its actual flight path. During maneuvers, pilots often fly at extreme angles of attack--with the nose pitched up while the aircraft continues in its original direction. This can lead to loss of control and result in the loss of the aircraft, or both. Three thrust-vectoring paddles made of graphite epoxy mounted on the X-31 aircraft exhaust nozzle directed the exhaust flow to provide control in pitch (up and down) and yaw (right and left) to improve control. The paddles can sustain heat of up to 1,500 degrees centigrade for extended periods of time. In addition the X-31 aircraft were configured with movable forward canards and fixed aft strakes. The canards were small wing-like structures set on the wing line between the nose and the leading edge of the wing. The strakes were set on the same line between the trailing edge of the wing and the engine exhaust. Both supplied additional control in tight maneuvering situations. The X-31 research program produced technical data at high angles of attack. This information is giving engineers and aircraft designers a better understanding of aerodynamics, effectiveness of flight controls and thrust

  16. X-31 in flight - Post Stall Maneuver

    NASA Technical Reports Server (NTRS)

    1995-01-01

    Two X-31 Enhanced Fighter Maneuverability (EFM) demonstrators were flown at Rockwell International's Palmdale, Calif., facility and the NASA Dryden Flight Research Center, Edwards, Calif., to obtain data that may apply to the design of highly-maneuverable next-generation fighters. The program had its first flight on Oct. 11, 1990, in Palmdale; it ended in June 1995. The X-31 program demonstrated the value of thrust vectoring (directing engine exhaust flow) coupled with advanced flight control systems, to provide controlled flight during close-in air combat at very high angles of attack. The result of this increased maneuverability is a significant advantage over conventional fighters. 'Angle-of-attack' (alpha) is an engineering term to describe the angle of an aircraft's body and wings relative to its actual flight path. During maneuvers, pilots often fly at extreme angles of attack -- with the nose pitched up while the aircraft continues in its original direction. This can lead to loss of control and result in the loss of the aircraft, pilot or both. Three thrust vectoring paddles made of graphite epoxy mounted on the X-31's exhaust nozzle directed the exhaust flow to provide control in pitch (up and down) and yaw (right and left) to improve control. The paddles can sustain heat of up to 1,500 degrees centigrade for extended periods of time. In addition the X-31s were configured with movable forward canards and fixed aft strakes. The canards were small wing-like structures set on the wing line between the nose and the leading edge of the wing. The strakes were set on the same line between the trailing edge of the wing and the engine exhaust. Both supplyied additional control in tight maneuvering situations. The X-31 research program produced technical data at high angles of attack. This information is giving engineers and aircraft designers a better understanding of aerodynamics, effectiveness of flight controls and thrust vectoring, and airflow phenomena at high

  17. Perseus in Flight

    NASA Technical Reports Server (NTRS)

    1991-01-01

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

  18. Gas-path seal technology

    NASA Technical Reports Server (NTRS)

    Zuk, J.

    1976-01-01

    Improved gas-path seals are needed for better fuel economy, longer performance retention, and lower maintenance, particularly in advanced, high-performance gas turbine engines. Problems encountered in gas-path sealing are described, as well as new blade-tip sealing approaches for high-pressure compressors and turbines. These include a lubricant coating for conventional, porous-metal, rub-strip materials used in compressors. An improved hot-press metal alloy shows promise to increase the operating surface temperatures of high-pressure-turbine, blade-tip seals to 1450 K (2150 F). Three ceramic seal materials are also described that have the potential to allow much higher gas-path surface operating temperatures than are possible with metal systems.

  19. HOPE real time flight operations analyses for return to earth phase, part A

    NASA Astrophysics Data System (ADS)

    1993-03-01

    The results of the HOPE (H-2 Orbiting Plane) real time flight operation analysis for return to earth phase are presented. The analyses of the flight parameter real time estimation accuracy was conducted (including definition of the estimate system operation, close examination of required function and programs, and study on the verification and experiment plans) and the following two items of the system verification and experiment are proposed: (1) utilization of the ETS-X (Engineering Test Satellite-X); and (2) utilization of mock-up landing experiment plane. The study on the limit of deviation from the flight path was conducted, and various factors to improve the flight path deviation are outlined.

  20. Innovative development path of ethnomedicines: the interpretation of the path.

    PubMed

    Zhu, Zhaoyun; Fu, Dehuan; Gui, Yali; Cui, Tao; Wang, Jingkun; Wang, Ting; Yang, Zhizhong; Niu, Yanfei; She, Zhennan; Wang, Li

    2017-03-01

    One of the primary purposes of the innovative development of ethnomedicines is to use their excellent safety and significant efficacy to serve a broader population. To achieve this purpose, modern scientific and technological means should be referenced, and relevant national laws and regulations as well as technical guides should be strictly followed to develop standards and to perform systemic research in producing ethnomedicines. Finally, ethnomedicines, which are applied to a limited extent in ethnic areas, can be transformed into safe, effective, and quality-controllable medical products to relieve the pain of more patients. The innovative development path of ethnomedicines includes the following three primary stages: resource study, standardized development research, and industrialization of the achievements and efforts for internationalization. The implementation of this path is always guaranteed by the research and development platform and the talent team. This article is based on the accumulation of long-term practice and is combined with the relevant disciplines, laws and regulations, and technical guidance from the research and development of ethnomedicines. The intention is to perform an in-depth analysis and explanation of the major research thinking, methods, contents, and technical paths involved in all stages of the innovative development path of ethnomedicines to provide useful references for the development of proper ethnomedicine use.

  1. Speckle Imaging Over Horizontal Paths

    SciTech Connect

    Carrano, C J

    2002-05-21

    Atmospheric aberrations reduce the resolution and contrast in surveillance images recorded over horizontal or slant paths. This paper describes our recent horizontal and slant path imaging experiments of extended scenes as well as the results obtained using speckle imaging. The experiments were performed with an 8-inch diameter telescope placed on either a rooftop or hillside and cover ranges of interest from 0.5 km up to 10 km. The scenery includes resolution targets, people, vehicles, and other structures. The improvement in image quality using speckle imaging is dramatic in many cases, and depends significantly upon the atmospheric conditions. We quantify resolution improvement through modulation transfer function measurement comparisons.

  2. 2001 Flight Mechanics Symposium

    NASA Technical Reports Server (NTRS)

    Lynch, John P. (Editor)

    2001-01-01

    This conference publication includes papers and abstracts presented at the Flight Mechanics Symposium held on June 19-21, 2001. Sponsored by the Guidance, Navigation and Control Center of Goddard Space Flight Center, this symposium featured technical papers on a wide range of issues related to attitude/orbit determination, prediction and control; attitude simulation; attitude sensor calibration; theoretical foundation of attitude computation; dynamics model improvements; autonomous navigation; constellation design and formation flying; estimation theory and computational techniques; Earth environment mission analysis and design; and, spacecraft re-entry mission design and operations.

  3. Soaring flight in Guinea

    NASA Technical Reports Server (NTRS)

    Idrac, P

    1920-01-01

    The term soaring is applied here to the flight of certain large birds which maneuver in the air without moving their wings. The author explains the methods of his research and here gives approximate figures for the soaring flight of the Egyptian Vulture and the African White backed Vulture. Figures are given in tabular form for relative air speed per foot per second, air velocity per foot per second, lift/drag ratio, and selected coefficients. The author argues that although the figures given were taken from a very limited series of observations, they have nevertheless thrown some light on the use by birds of the internal energy of the air.

  4. LSRA in flight

    NASA Technical Reports Server (NTRS)

    1993-01-01

    A NASA CV-990, modified as a Landing Systems Research Aircraft (LSRA), in flight over NASA's Dryden Flight Research Center, Edwards, California, for a test of the space shuttle landing gear system. The space shuttle landing gear test unit, operated by a high-pressure hydraulic system, allowed engineers to assess and document the performance of space shuttle main and nose landing gear systems, tires and wheel assemblies, plus braking and nose wheel steering performance. The series of 155 test missions for the space shuttle program provided extensive data about the life and endurance of the shuttle tire systems and helped raise the shuttle crosswind landing limits at Kennedy.

  5. ASTRID rocket flight test

    SciTech Connect

    Whitehead, J.C.; Pittenger, L.C.; Colella, N.J.

    1994-07-01

    On February 4, 1994, we successfully flight tested the ASTRID rocket from Vandenberg Air Force Base. The technology for this rocket originated in the Brilliant Pebbles program and represents a five-year development effort. This rocket demonstrated how our new pumped-propulsion technology-which reduced the total effective engine mass by more than one half and cut the tank mass to one fifth previous requirements-would perform in atmospheric flight. This demonstration paves the way for potential cost-effective uses of the new propulsion system in commercial aerospace vehicles, exploration of the planets, and defense applications.

  6. The Effect of Lift on Entry Corridor Depth and Guidance Requirements for the Return Lunar Flight

    NASA Technical Reports Server (NTRS)

    Wong, Thomas J.; Slye, Robert E.

    1961-01-01

    Corridors for manned vehicles are defined consistent with requirements for avoiding radiation exposure and for limiting values of peak deceleration. Use of lift increases the depth of the entry corridor. Mid-course guidance requirements appear to be critical only for the flight-path angle. Increasing the energy of the transport orbit increases the required guidance accuracy for the flight-path angle. Corrective thrust applied essentially parallel to the local horizontal produces the maximum change in perigee altitude for a given increment of velocity. Energy required to effect a given change in perigee altitude varies inversely with range measured from the center of the earth.

  7. Collision avoidance in commercial aircraft Free Flight via neural networks and non-linear programming.

    PubMed

    Christodoulou, Manolis A; Kontogeorgou, Chrysa

    2008-10-01

    In recent years there has been a great effort to convert the existing Air Traffic Control system into a novel system known as Free Flight. Free Flight is based on the concept that increasing international airspace capacity will grant more freedom to individual pilots during the enroute flight phase, thereby giving them the opportunity to alter flight paths in real time. Under the current system, pilots must request, then receive permission from air traffic controllers to alter flight paths. Understandably the new system allows pilots to gain the upper hand in air traffic. At the same time, however, this freedom increase pilot responsibility. Pilots face a new challenge in avoiding the traffic shares congested air space. In order to ensure safety, an accurate system, able to predict and prevent conflict among aircraft is essential. There are certain flight maneuvers that exist in order to prevent flight disturbances or collision and these are graded in the following categories: vertical, lateral and airspeed. This work focuses on airspeed maneuvers and tries to introduce a new idea for the control of Free Flight, in three dimensions, using neural networks trained with examples prepared through non-linear programming.

  8. Human Factors Affecting Pilot Performance in Vertical and Translational Instrument Flight.

    DTIC Science & Technology

    1983-12-01

    Corl, and Jensen, 1981). These advances in avionics capabilities, especially the explosion in low-cost, light-weight, and highly reliable computing...waypoints, VOR and TACAN information, course lines, deviation from desired course (and flight path prediction in some cases), time and distance to...display was developed such tizat control and display dynamics are directionally compatible. He als) provided flight prediction in both the horizontal

  9. Space Shuttle flight control system

    NASA Technical Reports Server (NTRS)

    Klinar, W. J.; Kubiak, E. T.; Peters, W. H.; Saldana, R. L.; Smith, E. E., Jr.; Stegall, H. W.

    1975-01-01

    The Space Shuttle is a control stabilized vehicle with control provided by an all digital, fly-by-wire flight control system. This paper gives a description of the several modes of flight control which correspond to the Shuttle mission phases. These modes are ascent flight control (including open loop first stage steering, the use of four computers operating in parallel and inertial guidance sensors), on-orbit flight control (with a discussion of reaction control, phase plane switching logic, jet selection logic, state estimator logic and OMS thrust vector control), entry flight control and TAEM (terminal area energy management to landing). Also discussed are redundancy management and backup flight control.

  10. Adaptive integral dynamic surface control of a hypersonic flight vehicle

    NASA Astrophysics Data System (ADS)

    Aslam Butt, Waseem; Yan, Lin; Amezquita S., Kendrick

    2015-07-01

    In this article, non-linear adaptive dynamic surface air speed and flight path angle control designs are presented for the longitudinal dynamics of a flexible hypersonic flight vehicle. The tracking performance of the control design is enhanced by introducing a novel integral term that caters to avoiding a large initial control signal. To ensure feasibility, the design scheme incorporates magnitude and rate constraints on the actuator commands. The uncertain non-linear functions are approximated by an efficient use of the neural networks to reduce the computational load. A detailed stability analysis shows that all closed-loop signals are uniformly ultimately bounded and the ? tracking performance is guaranteed. The robustness of the design scheme is verified through numerical simulations of the flexible flight vehicle model.

  11. Moving in a moving medium: new perspectives on flight.

    PubMed

    Shepard, Emily L C; Ross, Andrew N; Portugal, Steven J

    2016-09-26

    One of the defining features of the aerial environment is its variability; air is almost never still. This has profound consequences for flying animals, affecting their flight stability, speed selection, energy expenditure and choice of flight path. All these factors have important implications for the ecology of flying animals, and the ecosystems they interact with, as well as providing bio-inspiration for the development of unmanned aerial vehicles. In this introduction, we touch on the factors that drive the variability in airflows, the scales of variability and the degree to which given airflows may be predictable. We then summarize how papers in this volume advance our understanding of the sensory, biomechanical, physiological and behavioural responses of animals to air flows. Overall, this provides insight into how flying animals can be so successful in this most fickle of environments.This article is part of the themed issue 'Moving in a moving medium: new perspectives on flight'.

  12. The interpretation of flying qualities requirements for flight control design

    NASA Technical Reports Server (NTRS)

    Rynaski, E. G.; Weingarten, N. C.; Grantham, W.

    1986-01-01

    The flying requirements of MIL-F-8785(C) are interpreted in terms of command/response configurations, and pilot preference for flight control systems configurations of angle of attack, or pitch rate command, specified independently for the short period and phugoid dynamics, is determined using the Total-In-Flight-Simulator aircraft. The results show that for either command configuration, the short term response applies to the angle of attack response of the vehicle, and that this response must satisfy the omega(n) vs n/alpha requirement. The preference in the long term for angle of attack command indicates that the pilot wants the aircraft to fly in the direction it is pointing, and an attitude hold system is not found to be preferred unless attitude hold results in flight path angle hold.

  13. Career Paths in Environmental Sciences

    EPA Science Inventory

    Career paths, current and future, in the environmental sciences will be discussed, based on experiences and observations during the author's 40 + years in the field. An emphasis will be placed on the need for integrated, transdisciplinary systems thinking approaches toward achie...

  14. SSME propellant path leak detection

    NASA Technical Reports Server (NTRS)

    Crawford, Roger; Shohadaee, Ahmad Ali

    1989-01-01

    The complicated high-pressure cycle of the space shuttle main engine (SSME) propellant path provides many opportunities for external propellant path leaks while the engine is running. This mode of engine failure may be detected and analyzed with sufficient speed to save critical engine test hardware from destruction. The leaks indicate hardware failures which will damage or destroy an engine if undetected; therefore, detection of both cryogenic and hot gas leaks is the objective of this investigation. The primary objective of this phase of the investigation is the experimental validation of techniques for detecting and analyzing propellant path external leaks which have a high probability of occurring on the SSME. The selection of candidate detection methods requires a good analytic model for leak plumes which would develop from external leaks and an understanding of radiation transfer through the leak plume. One advanced propellant path leak detection technique is obtained by using state-of-the-art technology infrared (IR) thermal imaging systems combined with computer, digital image processing, and expert systems for the engine protection. The feasibility of IR leak plume detection is evaluated on subscale simulated laboratory plumes to determine sensitivity, signal to noise, and general suitability for the application.

  15. Career Path of School Superintendents.

    ERIC Educational Resources Information Center

    Mertz, Norma T.; McNeely, Sonja R.

    This study of the career paths of 147 Tennessee school superintendents sought to determine to what extent coaching and principalships are routes to that office. The majority of respondents were white males; only one was black, and 10 were female. The data were analyzed by group, race, sex, years in office, and method of selection (elected or…

  16. Employer Resource Manual. Project Path.

    ERIC Educational Resources Information Center

    Kane, Karen R.; Del George, Eve

    Project Path at Illinois' College of DuPage was established to provide pre-employment training and career counseling for disabled students. To encourage the integration of qualified individuals with disabilities into the workplace, the project compiled this resource manual for area businesses, providing tips for interacting with disabled people…

  17. Perceived Shrinkage of Motion Paths

    ERIC Educational Resources Information Center

    Sinico, Michele; Parovel, Giulia; Casco, Clara; Anstis, Stuart

    2009-01-01

    We show that human observers strongly underestimate a linear or circular trajectory that a luminous spot follows in the dark. At slow speeds, observers are relatively accurate, but, as the speed increases, the size of the path is progressively underestimated, by up to 35%. The underestimation imposes little memory load and does not require…

  18. QAM multi-path characterization due to ocean scattering

    SciTech Connect

    Petersen, T. L.; Bracht, R. R.; Pasquale, R. V.; Dimsdle, J.; Swanson, R.

    2002-01-01

    A series of RF channel flight characterization tests are to be run, in early March, to benchmark high speed, 16QAM multi-path performance over the ocean surface. The modulation format being tested is a 16 differential phase, absolute amplitude, two level polar quadrature amplitude modulation. The bit rate is 100 Megabits per second. This transmitted signal will be generated in a burst mode, being on for 40 microseconds once every 40 milliseconds. An aircraft will radiate the RF test signal at 5 different altitudes. The aircraft will make two inward flights at each altitude with vertical and horizontal polarization respectively. Receivers are to be placed in two different locations using circular antenna polarization. One receiver will be placed at an altitude of 230 feet above the ocean surface, and the other on a boat with the antenna placed just up off of the ocean surface. Data is to be collected over multiple wavelength changes in the difference between the line of sight and the reflected multi-path ray. The real time signal strength variation is to be recorded as well. Analysis of the resulting data will show flat fading and frequency selective fading effects. The test is run over two different days to provide for some variation in sea state conditions. This resulting information will help quantify the effectiveness of this novel modulation scheme for missile telemetry end event data applications.

  19. X-31 in flight - Herbst Turn

    NASA Technical Reports Server (NTRS)

    1995-01-01

    Two X-31 Enhanced Fighter Maneuverability (EFM) demonstrators were flown at the Rockwell International facility, Palmdale, California, and the NASA Dryden Flight Research Center, Edwards, California, to obtain data that may apply to the design of highly-maneuverable next-generation fighters. The program had its first flight on October 11, 1990, in Palmdale; it ended in June 1995. The X-31 program demonstrated the value of thrust vectoring (directing engine exhaust flow) coupled with advanced flight control systems, to provide controlled flight during close-in air combat at very high angles of attack. The result of this increased maneuverability is an airplane with a significant advantage over conventional fighters. 'Angle-of-attack' (alpha) is an engineering term to describe the angle of an aircraft body and wings relative to its actual flight path. During maneuvers, pilots often fly at extreme angles of attack -- with the nose pitched up while the aircraft continues in its original direction. This can lead to loss of control and result in the loss of the aircraft, pilot or both. Three thrust-vectoring paddles made of graphite epoxy mounted on the exhaust nozzle of the X-31 aircraft directed the exhaust flow to provide control in pitch (up and down) and yaw (right and left) to improve control. The paddles can sustain heat of up to 1,500 degrees centigrade for extended periods of time. In addition the X-31 aircraft were configured with movable forward canards and fixed aft strakes. The canards were small wing-like structures set on the wing line between the nose and the leading edge of the wing. The strakes were set on the same line between the trailing edge of the wing and the engine exhaust. Both supplied additional control in tight maneuvering situations. The X-31 research program produced technical data at high angles of attack. This information is giving engineers and aircraft designers a better understanding of aerodynamics, effectiveness of flight controls

  20. X-31 in flight - Double Reversal

    NASA Technical Reports Server (NTRS)

    1995-01-01

    Two X-31 Enhanced Fighter Maneuverability (EFM) demonstrators were flown at the Rockwell International facility, Palmdale, California, and the NASA Dryden Flight Research Center, Edwards, California, to obtain data that may apply to the design of highly-maneuverable next-generation fighters. The program had its first flight on October 11, 1990, in Palmdale; it ended in June 1995. The X-31 program demonstrated the value of thrust vectoring (directing engine exhaust flow) coupled with advanced flight control systems, to provide controlled flight during close-in air combat at very high angles of attack. The result of this increased maneuverability is an airplane with a significant advantage over conventional fighters. 'Angle-of-attack' (alpha) is an engineering term to describe the angle of an aircraft body and wings relative to its actual flight path. During maneuvers, pilots often fly at extreme angles of attack -- with the nose pitched up while he aircraft continues in its original direction. This can lead to loss of control and result in the loss of the aircraft, pilot or both. Three thrust-vectoring paddles made of graphite epoxy mounted on the exhaust nozzle of the X-31 aircraft directed the exhaust flow to provide control in pitch (up and down) and yaw (right and left) to improve control. The paddles can sustain heat of up to 1,500 degrees centigrade for extended periods of time. In addition the X-31 aircraft were configured with movable forward canards and fixed aft strakes. The canards were small wing-like structures set on the wing line between the nose and the leading edge of the wing. The strakes were set on the same line between the trailing edge of the wing and the engine exhaust. Both supplied additional control in tight maneuvering situations. The X-31 research program produced technical data at high angles of attack. This information is giving engineers and aircraft designers a better understanding of aerodynamics, effectiveness of flight controls and

  1. Insect Flight and MAVs

    DTIC Science & Technology

    2007-11-02

    flight u After 350 million years of evolution , they have probably found good solutions for – Kinematics – Wing design – Control Systems High-Lift...Plane Episyrphus balteatus Hoverflies, dragonflies , small birds and bats rely on dynamic stall on the downstroke (red) for weight support Fling

  2. Weather and Flight Testing

    NASA Technical Reports Server (NTRS)

    Wiley, Scott

    2007-01-01

    This viewgraph document reviews some of the weather hazards involved with flight testing. Some of the hazards reviewed are: turbulence, icing, thunderstorms and winds and windshear. Maps, pictures, satellite pictures of the meteorological phenomena and graphs are included. Also included are pictures of damaged aircraft.

  3. Flight Termination Criteria

    NASA Astrophysics Data System (ADS)

    Haber, Jerold M.; Larson, Erik

    2013-09-01

    The first line of defense in protecting the public against the threat of injury from a failing space booster is the flight termination system. Consequently, these systems must be highly reliable and the criteria for flight termination must be carefully formulated. Criteria must be developed based on observable data that allows adequate time for the data to be assessed and a flight termination action to be triggered. Criteria should be set so that 1) the chance a good vehicle will be terminated is small, 2) the chance of failing to terminate an errant vehicle before it can hazard population centers or valuable assets is minimal, and 3) there is assurance that the combination of the planned trajectory and mission rules do not induce excessive risks to land based populations, air lanes, and shipping lanes should the vehicle need to be terminated [1].This paper provides an overview of the approaches to developing and implement flight termination criteria and a tool for understanding risk implications of proposed criteria.

  4. White Flight: Some Hypotheses.

    ERIC Educational Resources Information Center

    Wegmann, Robert G.

    The available literature on white flight, or, more properly, school resegregation -- the phenomenon of white withdrawal (total or partial) from desegregated schools -- is reviewed in this paper which also reports some new research in this area. The distinction is made between those schools located on the fringes of the inner city, which first…

  5. Autonomous Formation Flight

    NASA Technical Reports Server (NTRS)

    Schkolnik, Gerard S.; Cobleigh, Brent

    2004-01-01

    NASA's Strategic Plan for the Aerospace Technology Enterprise includes ambitious objectives focused on affordable air travel, reduced emissions, and expanded aviation-system capacity. NASA Dryden Flight Research Center, in cooperation with NASA Ames Research Center, the Boeing Company, and the University of California, Los Angeles, has embarked on an autonomous-formation-flight project that promises to make significant strides towards these goals. For millions of years, birds have taken advantage of the aerodynamic benefit of flying in formation. The traditional "V" formation flown by many species of birds (including gulls, pelicans, and geese) enables each of the trailing birds to fly in the upwash flow field that exists just outboard of the bird immediately ahead in the formation. The result for each trailing bird is a decrease in induced drag and thus a reduction in the energy needed to maintain a given speed. Hence, for migratory birds, formation flight extends the range of the system of birds over the range of birds flying solo. The Autonomous Formation Flight (AFF) Project is seeking to extend this symbiotic relationship to aircraft.

  6. Flight Model Discharge System

    DTIC Science & Technology

    1989-09-01

    Itterconnection wiring diagram for the ESA ............................... 34 3-13 Typical gain versus total count curve for CEM...42 3-16 Calibration curve for energy bin 12 of the ion ESA ....................... 43 3-17 Flight ESA S/N001...Calibration curves for SPM S/N001 ......................................... 67 4-11 Calibration curves for SPM S/N002

  7. F-104 in flight

    NASA Technical Reports Server (NTRS)

    1993-01-01

    F-104G N826NA during a 1993 flight over the Mojave desert, outfitted with an experiment pylon under the center fuselage and wing racks. The F-104 was originally designed by Kelly Johnson of the Lockheed Skunk Works as a day fighter. The aircraft soon proved ideal for both research and training. For instance, a modified F-104 tested the reaction control jets for the X-15. The F-104's short wings and low lift to drag ratio made it ideal to simulate the X-15 landing profile, which the F-104s often undertook before X-15 flights in order to acquaint pilots with the rocket plane's landing characteristics. This training role continued with the lifting bodies. NASA F-104s were also used for high-speed research after the X-1E was retired. Finally, the F-104s were also used as chase planes for research missions. The F-104G was a late model designed as a fighter bomber for low-level strike missions. It was built for use by the West German Air Force and other foreign governments. N826NA accomplished a wide-range of research activities, including tests of the Space Shuttle's Thermal Protection System (TPS) tiles. The aircraft made 1,415 flights before being retired. It is now on display at the Dryden Flight Research Center.

  8. Flight Mechanics Symposium 1997

    NASA Technical Reports Server (NTRS)

    Walls, Donna M. (Editor)

    1997-01-01

    This conference publication includes papers and abstracts presented at the Flight Mechanics Symposium. This symposium featured technical papers on a wide range of issues related to orbit-attitude prediction, determination, and control; attitude sensor calibration; attitude determination error analysis; attitude dynamics; and orbit decay and maneuver strategy. Government, industry, and the academic community participated in the preparation and presentation of these papers.

  9. Flight telerobotic servicer legacy

    NASA Astrophysics Data System (ADS)

    Shattuck, Paul L.; Lowrie, James W.

    1992-11-01

    The Flight Telerobotic Servicer (FTS) was developed to enhance and provide a safe alternative to human presence in space. The first step for this system was a precursor development test flight (DTF-1) on the Space Shuttle. DTF-1 was to be a pathfinder for manned flight safety of robotic systems. The broad objectives of this mission were three-fold: flight validation of telerobotic manipulator (design, control algorithms, man/machine interfaces, safety); demonstration of dexterous manipulator capabilities on specific building block tasks; and correlation of manipulator performance in space with ground predictions. The DTF-1 system is comprised of a payload bay element (7-DOF manipulator with controllers, end-of-arm gripper and camera, telerobot body with head cameras and electronics module, task panel, and MPESS truss) and an aft flight deck element (force-reflecting hand controller, crew restraint, command and display panel and monitors). The approach used to develop the DTF-1 hardware, software and operations involved flight qualification of components from commercial, military, space, and R controller, end-of-arm tooling, force/torque transducer) and the development of the telerobotic system for space applications. The system is capable of teleoperation and autonomous control (advances state of the art); reliable (two-fault tolerance); and safe (man-rated). Benefits from the development flight included space validation of critical telerobotic technologies and resolution of significant safety issues relating to telerobotic operations in the Shuttle bay or in the vicinity of other space assets. This paper discusses the lessons learned and technology evolution that stemmed from developing and integrating a dexterous robot into a manned system, the Space Shuttle. Particular emphasis is placed on the safety and reliability requirements for a man-rated system as these are the critical factors which drive the overall system architecture. Other topics focused on include

  10. Spacewedge #1 in Flight

    NASA Technical Reports Server (NTRS)

    1992-01-01

    A Spacewedge subscale model, built to help develop potential autonomous recovery systems for spacecraft as well as methods for delivering large Army cargo loads to precision landings, maneuvers through the air under its steerable parafoil during 1992 flight testing. From October 1991 to December 1996, NASA Ames-Dryden Flight Research Facility (after 1994, the Dryden Flight Research Center, Edwards, California) conducted a research program know as the Spacecraft Autoland Project. This Project was designed to determine the feasibility of the autonomous recovery of a spacecraft using a ram-air parafoil system for the final stages of flight, including a precision landing. The Johnson Space Center and the U.S. Army participated in various phases of the program. The Charles Stark Draper Laboratory developed the software for Wedge 3 under contract to the Army. Four generic spacecraft (each called a Spacewedge or simply a Wedge) were built; the last one was built to test the feasibility of a parafoil for delivering Army cargoes. Technology developed during this program has applications for future spacecraft recovery systems, such as the X-38 Crew Return Vehicle demonstrator. The Spacewedge program demonstrated precision flare and landing into the wind at a predetermined location. The program showed that a flexible, deployable system using autonomous navigation and landing was a viable and practical way to recover spacecraft. NASA researchers conducted flight tests of the Spacewedge at three sites near Dryden, a hillside near Tehachapi, the Rogers Dry Lakebed at Edwards Air Force Base, and the California City Airport Drop Zone. During the first phase of testing 36 flights were made. Phase II consisted of 45 flights using a smaller parafoil. A third Phase of 34 flights was conducted primarily by the Army and resulted in the development of an Army guidance system for precision offset cargo delivery. The wedge used during the Army phase was not called a Spacewedge but simply a

  11. 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.)

  12. Spreading paths in partially observed social networks

    PubMed Central

    Onnela, Jukka-Pekka; Christakis, Nicholas A.

    2012-01-01

    Understanding how and how far information, behaviors, or pathogens spread in social networks is an important problem, having implications for both predicting the size of epidemics, as well as for planning effective interventions. There are, however, two main challenges for inferring spreading paths in real-world networks. One is the practical difficulty of observing a dynamic process on a network, and the other is the typical constraint of only partially observing a network. Using a static, structurally realistic social network as a platform for simulations, we juxtapose three distinct paths: (1) the stochastic path taken by a simulated spreading process from source to target; (2) the topologically shortest path in the fully observed network, and hence the single most likely stochastic path, between the two nodes; and (3) the topologically shortest path in a partially observed network. In a sampled network, how closely does the partially observed shortest path (3) emulate the unobserved spreading path (1)? Although partial observation inflates the length of the shortest path, the stochastic nature of the spreading process also frequently derails the dynamic path from the shortest path. We find that the partially observed shortest path does not necessarily give an inflated estimate of the length of the process path; in fact, partial observation may, counterintuitively, make the path seem shorter than it actually is. PMID:22587148

  13. U.S. Airline Transport Pilot International Flight Language Experiences, Report 6: Native English-Speaking Controllers Communicating With Non-Native English-Speaking Pilots

    DTIC Science & Technology

    2011-03-01

    English - speaking pilot and you are on the same flight path and you suspect that pilot is low in English language proficiency skills ...native speaker of English (or English dialect). 2. Controllers need to develop greater patience with non-native English - speaking pilots. Once interna...when a non-native English - speaking pilot and you are on the same flight path and you suspect that pilot is low in English language proficiency skills

  14. The NASA Flight Demonstration Program

    NASA Technical Reports Server (NTRS)

    Levin, G. M.; Routh, D.

    1985-01-01

    The Flight Demonstration Program was initiated by the Office of Space Flight in October 1983. The purposes of this program are to conduct an ongoing series of flight demonstrations which demonstrate critical enabling technology to potential Shuttle users and at the same time provide hands on experience to NASA engineers. Flight demonstrations are selected through a peer review process in response to an annual solicitation issued by the Flight Demonstration Office at NASA Headquarters. As of July 1985 one major flight demonstration has been successfully conducted, two flight demonstrations are scheduled to fly in November on STS 61-B, and five flight demonstrations are in various stages of development and planned to be flown during the next three years.

  15. Boeing flight deck design philosophy

    NASA Technical Reports Server (NTRS)

    Stoll, Harty

    1990-01-01

    Information relative to Boeing flight deck design philosophy is given in viewgraph form. Flight deck design rules, design considerations, functions allocated to the crew, redundancy and automation concerns, and examples of accident data that were reviewed are listed.

  16. Effect of light intensity on flight control and temporal properties of photoreceptors in bumblebees.

    PubMed

    Reber, Therese; Vähäkainu, Antti; Baird, Emily; Weckström, Matti; Warrant, Eric; Dacke, Marie

    2015-05-01

    To control flight, insects rely on the pattern of visual motion generated on the retina as they move through the environment. When light levels fall, vision becomes less reliable and flight control thus becomes more challenging. Here, we investigated the effect of light intensity on flight control by filming the trajectories of free-flying bumblebees (Bombus terrestris, Linnaeus 1758) in an experimental tunnel at different light levels. As light levels fell, flight speed decreased and the flight trajectories became more tortuous but the bees were still remarkably good at centring their flight about the tunnel's midline. To investigate whether this robust flight performance can be explained by visual adaptations in the bumblebee retina, we also examined the response speed of the green-sensitive photoreceptors at the same light intensities. We found that the response speed of the photoreceptors significantly decreased as light levels fell. This indicates that bumblebees have both behavioural (reduction in flight speed) and retinal (reduction in response speed of the photoreceptors) adaptations to allow them to fly in dim light. However, the more tortuous flight paths recorded in dim light suggest that these adaptations do not support flight with the same precision during the twilight hours of the day.

  17. Enzymatic reaction paths as determined by transition path sampling

    NASA Astrophysics Data System (ADS)

    Masterson, Jean Emily

    Enzymes are biological catalysts capable of enhancing the rates of chemical reactions by many orders of magnitude as compared to solution chemistry. Since the catalytic power of enzymes routinely exceeds that of the best artificial catalysts available, there is much interest in understanding the complete nature of chemical barrier crossing in enzymatic reactions. Two specific questions pertaining to the source of enzymatic rate enhancements are investigated in this work. The first is the issue of how fast protein motions of an enzyme contribute to chemical barrier crossing. Our group has previously identified sub-picosecond protein motions, termed promoting vibrations (PVs), that dynamically modulate chemical transformation in several enzymes. In the case of human heart lactate dehydrogenase (hhLDH), prior studies have shown that a specific axis of residues undergoes a compressional fluctuation towards the active site, decreasing a hydride and a proton donor--acceptor distance on a sub-picosecond timescale to promote particle transfer. To more thoroughly understand the contribution of this dynamic motion to the enzymatic reaction coordinate of hhLDH, we conducted transition path sampling (TPS) using four versions of the enzymatic system: a wild type enzyme with natural isotopic abundance; a heavy enzyme where all the carbons, nitrogens, and non-exchangeable hydrogens were replaced with heavy isotopes; and two versions of the enzyme with mutations in the axis of PV residues. We generated four separate ensembles of reaction paths and analyzed each in terms of the reaction mechanism, time of barrier crossing, dynamics of the PV, and residues involved in the enzymatic reaction coordinate. We found that heavy isotopic substitution of hhLDH altered the sub-picosecond dynamics of the PV, changed the favored reaction mechanism, dramatically increased the time of barrier crossing, but did not have an effect on the specific residues involved in the PV. In the mutant systems

  18. Cardiovascular physiology in space flight

    NASA Technical Reports Server (NTRS)

    Charles, John B.; Bungo, Michael W.

    1991-01-01

    The effects of space flight on the cardiovascular system have been studied since the first manned flights. In several instances, the results from these investigations have directly contradicted the predictions based on established models. Results suggest associations between space flight's effects on other organ systems and those on the cardiovascular system. Such findings provide new insights into normal human physiology. They must also be considered when planning for the safety and efficiency of space flight crewmembers.

  19. YF-12 in flight

    NASA Technical Reports Server (NTRS)

    1972-01-01

    The Flight Research Center's involvement with the YF-12A, an interceptor version of the Lockheed A-12, began in 1967. Ames Research Center was interested in using wind tunnel data that had been generated at Ames under extreme secrecy. Also, the Office of Advanced Research and Technology (OART) saw the YF-12A as a means to advance high-speed technology, which would help in designing the Supersonic Transport (SST). The Air Force needed technical assistance to get the latest reconnaissance version of the A-12 family, the SR-71A, fully operational. Eventually, the Air Force offered NASA the use of two YF-12A aircraft, 60-6935 and 60-6936. A joint NASA-USAF program was mapped out in June 1969. NASA and Air Force technicians spent three months readying 935 for flight. On 11 December 1969, the flight program got underway with a successful maiden flight piloted by Col. Joe Rogers and Maj. Gary Heidelbaugh of the SR-71/F-12 Test Force. During the program, the Air Force concentrated on military applications, and NASA pursued a loads research program. NASA studies included inflight heating, skin-friction cooling, 'coldwall' research (a heat transfer experiment), flowfield studies, shaker vane research, and tests in support of the Space Shuttle landing program. Ultimately, 935 became the workhorse of the program, with 146 flights between 11 December 1969 and 7 November 1979. The second YF-12A, 936, made 62 flights. It was lost in a non-fatal crash on 24 June 1971. It was replaced by the so-called YF-12C (SR-71A 61-7951, modified with YF-12A inlets and engines and a bogus tail number 06937). The Lockheed A-12 family, known as the Blackbirds, were designed by Clarence 'Kelly' Johnson. They were constructed mostly of titanium to withstand aerodynamic heating. Fueled by JP-7, the Blackbirds were capable of cruising at Mach 3.2 and attaining altitudes in excess of 80,000 feet. The first version, a CIA reconnaissance aircraft that first flew in April 1962 was called the A-12. An

  20. NASA Dryden Flight Research Center

    NASA Technical Reports Server (NTRS)

    Navarro, Robert

    2009-01-01

    This DVD has several short videos showing some of the work that Dryden is involved in with experimental aircraft. These are: shots showing the Active AeroElastic Wing (AAW) loads calibration tests, AAW roll maneuvers, AAW flight control surface inputs, Helios flight, and takeoff, and Pathfinder takeoff, flight and landing.

  1. Flight crew health stabilization program

    NASA Technical Reports Server (NTRS)

    Wooley, B. C.; Mccollum, G. W.

    1975-01-01

    The flight crew health stabilization program was developed to minimize or eliminate the possibility of adverse alterations in the health of flight crews during immediate preflight, flight, and postflight periods. The elements of the program, which include clinical medicine, immunology, exposure prevention, and epidemiological surveillance, are discussed briefly. No crewmember illness was reported for the missions for which the program was in effect.

  2. A Hybrid Metaheuristic DE/CS Algorithm for UCAV Three-Dimension Path Planning

    PubMed Central

    Wang, Gaige; Guo, Lihong; Duan, Hong; Wang, Heqi; Liu, Luo; Shao, Mingzhen

    2012-01-01

    Three-dimension path planning for uninhabited combat air vehicle (UCAV) is a complicated high-dimension optimization problem, which primarily centralizes on optimizing the flight route considering the different kinds of constrains under complicated battle field environments. A new hybrid metaheuristic differential evolution (DE) and cuckoo search (CS) algorithm is proposed to solve the UCAV three-dimension path planning problem. DE is applied to optimize the process of selecting cuckoos of the improved CS model during the process of cuckoo updating in nest. The cuckoos can act as an agent in searching the optimal UCAV path. And then, the UCAV can find the safe path by connecting the chosen nodes of the coordinates while avoiding the threat areas and costing minimum fuel. This new approach can accelerate the global convergence speed while preserving the strong robustness of the basic CS. The realization procedure for this hybrid metaheuristic approach DE/CS is also presented. In order to make the optimized UCAV path more feasible, the B-Spline curve is adopted for smoothing the path. To prove the performance of this proposed hybrid metaheuristic method, it is compared with basic CS algorithm. The experiment shows that the proposed approach is more effective and feasible in UCAV three-dimension path planning than the basic CS model. PMID:23193383

  3. A fixed-base simulation study of two STOL aircraft flying curved, descending instrument approach paths

    NASA Technical Reports Server (NTRS)

    Benner, M. S.; Sawyer, R. H.; Mclaughlin, M. D.

    1973-01-01

    A real-time, fixed-base simulation study has been conducted to determine the curved, descending approach paths (within passenger-comfort limits) that would be acceptable to pilots, the flight-director-system logic requirements for curved-flight-path guidance, and the paths which can be flown within proposed microwave landing system (MLS) coverage angles. Two STOL aircraft configurations were used in the study. Generally, no differences in the results between the two STOL configurations were found. The investigation showed that paths with a 1828.8 meter turn radius and a 1828.8 meter final-approach distance were acceptable without winds and with winds up to at least 15 knots for airspeeds from 75 to 100 knots. The altitude at roll-out from the final turn determined which final-approach distances were acceptable. Pilots preferred to have an initial straight leg of about 1 n. mi. after MLS guidance acquisition before turn intercept. The size of the azimuth coverage angle necessary to meet passenger and pilot criteria depends on the size of the turn angle: plus or minus 60 deg was adequate to cover all paths execpt ones with a 180 deg turn.

  4. Bisphosphonate ISS Flight Experiment

    NASA Technical Reports Server (NTRS)

    LeBlanc, Adrian; Matsumoto, Toshio; Jones, Jeffrey; Shapiro, Jay; Lang, Thomas; Shackleford, Linda; Smith, Scott M.; Evans, Harlan; Spector, Elizabeth; Ploutz-Snyder, Robert; Sibonga, Jean; Keyak, Joyce; Nakamura, Toshitaka; Kohri, Kenjiro; Ohshima, Hiroshi; Moralez, Gilbert

    2014-01-01

    The bisphosphonate study is a collaborative effort between the NASA and JAXA space agencies to investigate the potential for antiresorptive drugs to mitigate bone changes associated with long-duration spaceflight. Elevated bone resorption is a hallmark of human spaceflight and bed rest (common zero-G analog). We tested whether an antiresorptive drug in combination with in-flight exercise would ameliorate bone loss and hypercalcuria during longduration spaceflight. Measurements include DXA, QCT, pQCT, and urine and blood biomarkers. We have completed analysis of 7 crewmembers treated with alendronate during flight and the immediate postflight (R+<2 week) data collection in 5 of 10 controls without treatment. Both groups used the advanced resistive exercise device (ARED) during their missions. We previously reported the pre/postflight results of crew taking alendronate during flight (Osteoporosis Int. 24:2105-2114, 2013). The purpose of this report is to present the 12-month follow-up data in the treated astronauts and to compare these results with preliminary data from untreated crewmembers exercising with ARED (ARED control) or without ARED (Pre-ARED control). Results: the table presents DXA and QCT BMD expressed as percentage change from preflight in the control astronauts (18 Pre-ARED and the current 5 ARED-1-year data not yet available) and the 7 treated subjects. As shown previously the combination of exercise plus antiresorptive is effective in preventing bone loss during flight. Bone measures for treated subjects, 1 year after return from space remain at or near baseline values. Except in one region, the treated group maintained or gained bone 1 year after flight. Biomarker data are not currently available for either control group and therefore not presented. However, data from other studies with or without ARED show elevated bone resorption and urinary Ca excretion while bisphosphonate treated subjects show decreases during flight. Comparing the two control

  5. Automatic layout of integrated-optics time-of-flight circuits

    NASA Astrophysics Data System (ADS)

    Kennett-Fogg, Ruth D.

    1995-04-01

    This work describes the architecture and algorithms used in the computer aided design tool developed for the automatic layout of integrated optic, time of flight circuit designs. This is similar to the layout of electronic VLSI circuits, where total wire length and chip area minimization are the major goals. Likewise, total wire length and chip area minimization are also the goals in the layout of time of flight circuits. However, there are two major differences between the layout of time of flight circuits and VLSI circuits. First, the interconnection lengths of time of flight designs are exactly specified in order to achieve the necessary delays for signal synchronization. Secondly, the switching elements are 120 times longer than they are wide. This highly astigmatic aspect ratio causes severe constraints on how and where the switches are placed. The assumed development of integrated corner turning mirrors allows the use of a parallel, row based device placement architecture and a rectangular, fixed grid track system for the connecting paths. The layout process proceeds in two steps. The first step involves the use of a partial circuit graph representation to place the elements in rows, oriented in the direction of the signal flow. After iterative improvement of the placement, the second step proceeds with the routing of the connecting paths. The main problem in the automatic layout of time of flight circuits is achieving the correct path lengths without overlapping previously routed paths. This problem is solved by taking advantage of a certain degree of variability present in each path, allowing the use of simple heuristics to circumvent previously routed paths.

  6. Conceptual Design of a Tiltrotor Transport Flight Deck

    NASA Technical Reports Server (NTRS)

    Decker, William A.; Dugan, Daniel C.; Simmons, Rickey C.; Tucker, George E.; Aiken, Edwin W. (Technical Monitor)

    1995-01-01

    A tiltrotor transport has considerable potential as a regional transport, increasing the air transportation system capacity by off-loading conventional runways. Such an aircraft will have a flight deck suited to its air transportation task and adapted to unique urban vertiport operating requirements. Such operations are likely to involve steep, slow instrument approaches for vertical and extremely short rolling take-offs and landings. While much of a tiltrotor transport's operations will be in common with commercial fixed-wing operations, terminal area operations will impose alternative flight deck design solutions. Control systems, displays and guidance, and control inceptors must be tailored to both routine and emergency vertical flight operations. This paper will survey recent experience with flight deck design elements suitable to a tiltrotor transport and will propose a conceptual cockpit design for such an aircraft. A series of piloted simulations using the NASA Ames Vertical Motion Simulator have investigated cockpit design elements and operating requirements for tiltrotor transports operating into urban vertiports. These experiments have identified the need for a flight director or equivalent display guidance for steep final approaches. A flight path vector display format has proven successful for guiding tiltrotor transport terminal area operations. Experience with a Head-Up Display points to the need for a bottom-mounted display device to maximize its utility on steep final approach paths. Configuration control (flap setting and nacelle angle) requires appropriate augmentation and tailoring for civil transport operations, flown to an airline transport pilot instrument flight rules (ATP-IFR) standard. The simulation experiments also identified one thrust control lever geometry as inappropriate to the task and found at least acceptable results with the vertical thrust control lever of the XV-15. In addition to the thrust controller, the attitude control of

  7. 14 CFR 121.414 - Initial and transition training and checking requirements: flight instructors (airplane), flight...

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ....414 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED... training for flight instructors (airplane), flight engineer instructors (airplane), and flight navigator... instruction. (4) For flight engineer instructors (airplane) and flight navigator instructors (airplane),...

  8. Effects of space flight on locomotor control

    NASA Technical Reports Server (NTRS)

    Bloomberg, Jacob J.; Layne, Charles S.; McDonald, P. Vernon; Peters, Brian T.; Huebner, William P.; Reschke, Millard F.; Berthoz, Alain; Glasauer, Stefan; Newman, Dava; Jackson, D. Keoki

    1999-01-01

    In the microgravity environment of spaceflight, the relationship between sensory input and motor output is altered. During prolonged missions, neural adaptive processes come into play to recalibrate central nervous system function, thereby permitting new motor control strategies to emerge in the novel sensory environment of microgravity. However, the adaptive state achieved during spaceflight is inappropriate for a unit gravity environment and leads to motor control alterations upon return to Earth that include disturbances in locomotion. Indeed, gait and postural instabilities following the return to Earth have been reported in both U.S. astronauts and Russian cosmonauts even after short duration (5- to 10-day) flights. After spaceflight, astronauts may: (1) experience the sensation of turning while attempting to walk a straight path, (2) encounter sudden loss of postural stability, especially when rounding corners, (3) perceive exaggerated pitch and rolling head movements during walking, (4) experience sudden loss of orientation in unstructured visual environments, or (5) experience significant oscillopsia during locomotion.

  9. Time-of-Flight Microwave Camera.

    PubMed

    Charvat, Gregory; Temme, Andrew; Feigin, Micha; Raskar, Ramesh

    2015-10-05

    Microwaves can penetrate many obstructions that are opaque at visible wavelengths, however microwave imaging is challenging due to resolution limits associated with relatively small apertures and unrecoverable "stealth" regions due to the specularity of most objects at microwave frequencies. We demonstrate a multispectral time-of-flight microwave imaging system which overcomes these challenges with a large passive aperture to improve lateral resolution, multiple illumination points with a data fusion method to reduce stealth regions, and a frequency modulated continuous wave (FMCW) receiver to achieve depth resolution. The camera captures images with a resolution of 1.5 degrees, multispectral images across the X frequency band (8 GHz-12 GHz), and a time resolution of 200 ps (6 cm optical path in free space). Images are taken of objects in free space as well as behind drywall and plywood. This architecture allows "camera-like" behavior from a microwave imaging system and is practical for imaging everyday objects in the microwave spectrum.

  10. Uavrc, a Generic Mav Flight Assistance Software

    NASA Astrophysics Data System (ADS)

    Israel, M.; Mende, M.; Keim, S.

    2015-08-01

    In this paper we present our multicopter flight assistance software uavRC, which bears on a distributed system with interchangeable MAV-drivers and a browser-based user interface that can be used on any computer, tablet or smartphone. The software components can be distributed on different computers and are even executable on a Raspberry Pi. The components communicate over a well-defined interface. One module is the browser based user interface, another module is the MAV driver. There are additional modules like a task-scheduler, a path-planer and many more. Currently the software is in beta stage, so there is still a lot of work in progress. With this paper we focus on the software architecture.

  11. 14 CFR 91.109 - Flight instruction; Simulated instrument flight and certain flight tests.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... certain flight tests. (a) No person may operate a civil aircraft (except a manned free balloon) that is... used for a flight test for an airline transport pilot certificate or a class or type rating on...

  12. Flight of a UV spectrophotometer aboard Galileo 2, the NASA Convair 990 aircraft

    NASA Technical Reports Server (NTRS)

    Sellers, B.; Hunderwadel, J. L.; Hanser, F. A.

    1976-01-01

    An ultraviolet interference-filter spectrophotometer (UVS) fabricated for aircraft-borne use on the DOT Climatic Impact Assessment Program (CIAP) has been successfully tested in a series of flights on the NASA Convair 990, Galileo II. UV flux data and the calculated total ozone above the flight path are reported for several of the flights. Good agreement is obtained with the total ozone as deducted by integration of an ozone sonde vertical profile obtained at Wallops Island, Virginia near the time of a CV-990 underpass. Possible advantages of use of the UVS in the NASA Global Atmospheric Sampling Program are discussed.

  13. Methodology of a combined ground based testing and numerical modelling analysis of supersonic combustion flow paths

    NASA Astrophysics Data System (ADS)

    Hannemann, Klaus; Karl, Sebastian; Martinez Schramm, Jan; Steelant, Johan

    2010-10-01

    In the framework of the European Commission co-funded LAPCAT (Long-Term Advanced Propulsion Concepts and Technologies) project, the methodology of a combined ground-based testing and numerical modelling analysis of supersonic combustion flow paths was established. The approach is based on free jet testing of complete supersonic combustion ramjet (scramjet) configurations consisting of intake, combustor and nozzle in the High Enthalpy Shock Tunnel Göttingen (HEG) of the German Aerospace Center (DLR) and computational fluid dynamics studies utilising the DLR TAU code. The capability of the established methodology is demonstrated by applying it to the flow path of the generic HyShot II scramjet flight experiment configuration.

  14. Physarum can compute shortest paths.

    PubMed

    Bonifaci, Vincenzo; Mehlhorn, Kurt; Varma, Girish

    2012-09-21

    Physarum polycephalum is a slime mold that is apparently able to solve shortest path problems. A mathematical model has been proposed by Tero et al. (Journal of Theoretical Biology, 244, 2007, pp. 553-564) to describe the feedback mechanism used by the slime mold to adapt its tubular channels while foraging two food sources s(0) and s(1). We prove that, under this model, the mass of the mold will eventually converge to the shortest s(0)-s(1) path of the network that the mold lies on, independently of the structure of the network or of the initial mass distribution. This matches the experimental observations by Tero et al. and can be seen as an example of a "natural algorithm", that is, an algorithm developed by evolution over millions of years.

  15. Path similarity skeleton graph matching.

    PubMed

    Bai, Xiang; Latecki, Longin Jan

    2008-07-01

    This paper presents a novel framework to for shape recognition based on object silhouettes. The main idea is to match skeleton graphs by comparing the shortest paths between skeleton endpoints. In contrast to typical tree or graph matching methods, we completely ignore the topological graph structure. Our approach is motivated by the fact that visually similar skeleton graphs may have completely different topological structures. The proposed comparison of shortest paths between endpoints of skeleton graphs yields correct matching results in such cases. The skeletons are pruned by contour partitioning with Discrete Curve Evolution, which implies that the endpoints of skeleton branches correspond to visual parts of the objects. The experimental results demonstrate that our method is able to produce correct results in the presence of articulations, stretching, and occlusion.

  16. Becoming a flight surgeon.

    PubMed

    Gallé-Tessonneau, J R

    1988-12-01

    This text is the inaugural lesson given by the Professor of Aeronautic Psychiatry and starts the training period for new flight surgeons in the French Air Force. Introducing the French Air Force Medicine Training Session, the author speaks about the psychological aspects in aviation medicine. Three points of pilots' psychology are developed: 1) the pilot's body as the source of intense sensations and as an object of important value; 2) the libidinal, narcissistic, and defensive aspects of the pilot's spirit; and 3) the pilot's environment with its characteristic relationships. These facts influence the medical approach and modify the physician-pilot relationship. The flight surgeon must pay attention and get ready for this specific practice.

  17. Optimal symmetric flight studies

    NASA Technical Reports Server (NTRS)

    Weston, A. R.; Menon, P. K. A.; Bilimoria, K. D.; Cliff, E. M.; Kelley, H. J.

    1985-01-01

    Several topics in optimal symmetric flight of airbreathing vehicles are examined. In one study, an approximation scheme designed for onboard real-time energy management of climb-dash is developed and calculations for a high-performance aircraft presented. In another, a vehicle model intermediate in complexity between energy and point-mass models is explored and some quirks in optimal flight characteristics peculiar to the model uncovered. In yet another study, energy-modelling procedures are re-examined with a view to stretching the range of validity of zeroth-order approximation by special choice of state variables. In a final study, time-fuel tradeoffs in cruise-dash are examined for the consequences of nonconvexities appearing in the classical steady cruise-dash model. Two appendices provide retrospective looks at two early publications on energy modelling and related optimal control theory.

  18. Squeezed states and path integrals

    NASA Technical Reports Server (NTRS)

    Daubechies, Ingrid; Klauder, John R.

    1992-01-01

    The continuous-time regularization scheme for defining phase-space path integrals is briefly reviewed as a method to define a quantization procedure that is completely covariant under all smooth canonical coordinate transformations. As an illustration of this method, a limited set of transformations is discussed that have an image in the set of the usual squeezed states. It is noteworthy that even this limited set of transformations offers new possibilities for stationary phase approximations to quantum mechanical propagators.

  19. Flight Day 2 Highlights

    NASA Technical Reports Server (NTRS)

    2003-01-01

    The STS-107 second flight day begins with a shot of the Spacehab Research Double Module. Live presentations of experiments underway inside of the Spacehab Module are presented. Six experiments are shown. As part of the Space Technology and Research Student Payload, students from Australia, China, Israel, Japan, New York, and Liechtenstein are studying the effect that microgravity has on ants, spiders, silkworms, fish, bees, granular materials, and crystals. Mission Specialist Kalpana Chawla is seen working with the zeolite crystal growth experiment.

  20. MARS Flight Engineering Status

    SciTech Connect

    Fast, James E.; Dorow, Kevin E.; Morris, Scott J.; Thompson, Robert C.; Willett, Jesse A.

    2010-04-06

    The Multi-sensor Airborne Radiation Survey Flight Engineering project (MARS FE) has designed a high purity germanium (HPGe) crystal array for conducting a wide range of field measurements. In addition to the HPGe detector system, a platform-specific shock and vibration isolation system and environmental housing have been designed to support demonstration activities in a maritime environment on an Unmanned Surface Vehicle (USV). This report describes the status of the equipment as of the end of FY09.

  1. Infrared Thermography Flight Experimentation

    NASA Technical Reports Server (NTRS)

    Blanchard, Robert C.; Carter, Matthew L.; Kirsch, Michael

    2003-01-01

    Analysis was done on IR data collected by DFRC on May 8, 2002. This includes the generation of a movie to initially examine the IR flight data. The production of the movie was challenged by the volume of data that needed to be processed, namely 40,500 images with each image (256 x 252) containing over 264 million points (pixel depth 4096). It was also observed during the initial analysis that the RTD surface coating has a different emissivity than the surroundings. This fact added unexpected complexity in obtaining a correlation between RTD data and IR data. A scheme was devised to generate IR data near the RTD location which is not affected by the surface coating This scheme is valid as long as the surface temperature as measured does not change too much over a few pixel distances from the RTD location. After obtaining IR data near the RTD location, it is possible to make a direct comparison with the temperature as measured during the flight after adjusting for the camera s auto scaling. The IR data seems to correlate well to the flight temperature data at three of the four RID locations. The maximum count intensity occurs closely to the maximum temperature as measured during flight. At one location (RTD #3), there is poor correlation and this must be investigated before any further progress is possible. However, with successful comparisons at three locations, it seems there is great potential to be able to find a calibration curve for the data. Moreover, as such it will be possible to measure temperature directly from the IR data in the near future.

  2. Neural Flight Control System

    NASA Technical Reports Server (NTRS)

    Gundy-Burlet, Karen

    2003-01-01

    The Neural Flight Control System (NFCS) was developed to address the need for control systems that can be produced and tested at lower cost, easily adapted to prototype vehicles and for flight systems that can accommodate damaged control surfaces or changes to aircraft stability and control characteristics resulting from failures or accidents. NFCS utilizes on a neural network-based flight control algorithm which automatically compensates for a broad spectrum of unanticipated damage or failures of an aircraft in flight. Pilot stick and rudder pedal inputs are fed into a reference model which produces pitch, roll and yaw rate commands. The reference model frequencies and gains can be set to provide handling quality characteristics suitable for the aircraft of interest. The rate commands are used in conjunction with estimates of the aircraft s stability and control (S&C) derivatives by a simplified Dynamic Inverse controller to produce virtual elevator, aileron and rudder commands. These virtual surface deflection commands are optimally distributed across the aircraft s available control surfaces using linear programming theory. Sensor data is compared with the reference model rate commands to produce an error signal. A Proportional/Integral (PI) error controller "winds up" on the error signal and adds an augmented command to the reference model output with the effect of zeroing the error signal. In order to provide more consistent handling qualities for the pilot, neural networks learn the behavior of the error controller and add in the augmented command before the integrator winds up. In the case of damage sufficient to affect the handling qualities of the aircraft, an Adaptive Critic is utilized to reduce the reference model frequencies and gains to stay within a flyable envelope of the aircraft.

  3. Flight Crew Health Maintenance

    NASA Technical Reports Server (NTRS)

    Gullett, C. C.

    1970-01-01

    The health maintenance program for commercial flight crew personnel includes diet, weight control, and exercise to prevent heart disease development and disability grounding. The very high correlation between hypertension and overweight in cardiovascular diseases significantly influences the prognosis for a coronary prone individual and results in a high rejection rate of active military pilots applying for civilian jobs. In addition to physical fitness the major items stressed in pilot selection are: emotional maturity, glucose tolerance, and family health history.

  4. Dryden Flight Research Center

    NASA Technical Reports Server (NTRS)

    Kostyk, Christopher Barry

    2007-01-01

    As part of a session at the 2007 Thermal & Fluids Analysis Workshop (TFAWS), an overview of the operations at NASA Dryden Flight Research Center was given. Mission support at this site includes the Aeronautics Research Mission Directorate (ARMD); Exploration Systems Mission Directorate (ESMD), Science - ER-2; Science - G3 UAVSAR; Science - Ikhana and Space Operations. In addition, the presentation describes TFAWS related work at Dryden.

  5. Flight Software Math Library

    NASA Technical Reports Server (NTRS)

    McComas, David

    2013-01-01

    The flight software (FSW) math library is a collection of reusable math components that provides typical math utilities required by spacecraft flight software. These utilities are intended to increase flight software quality reusability and maintainability by providing a set of consistent, well-documented, and tested math utilities. This library only has dependencies on ANSI C, so it is easily ported. Prior to this library, each mission typically created its own math utilities using ideas/code from previous missions. Part of the reason for this is that math libraries can be written with different strategies in areas like error handling, parameters orders, naming conventions, etc. Changing the utilities for each mission introduces risks and costs. The obvious risks and costs are that the utilities must be coded and revalidated. The hidden risks and costs arise in miscommunication between engineers. These utilities must be understood by both the flight software engineers and other subsystem engineers (primarily guidance navigation and control). The FSW math library is part of a larger goal to produce a library of reusable Guidance Navigation and Control (GN&C) FSW components. A GN&C FSW library cannot be created unless a standardized math basis is created. This library solves the standardization problem by defining a common feature set and establishing policies for the library s design. This allows the libraries to be maintained with the same strategy used in its initial development, which supports a library of reusable GN&C FSW components. The FSW math library is written for an embedded software environment in C. This places restrictions on the language features that can be used by the library. Another advantage of the FSW math library is that it can be used in the FSW as well as other environments like the GN&C analyst s simulators. This helps communication between the teams because they can use the same utilities with the same feature set and syntax.

  6. X-29 flight maneuvers

    NASA Technical Reports Server (NTRS)

    1989-01-01

    Two X-29 aircraft, featuring one of the most unusual designs in aviation history, were flown at the NASA Dryden Flight Research Center, Edwards, Calif., as technology demonstrators to investigate a host of advanced concepts and technologies. This 30-second clip of air-to-air footage shows the X-29 as it makes hard left and right aileron turns followed up with a few barrel rolls.

  7. Advanced flight control system study

    NASA Technical Reports Server (NTRS)

    Hartmann, G. L.; Wall, J. E., Jr.; Rang, E. R.; Lee, H. P.; Schulte, R. W.; Ng, W. K.

    1982-01-01

    A fly by wire flight control system architecture designed for high reliability includes spare sensor and computer elements to permit safe dispatch with failed elements, thereby reducing unscheduled maintenance. A methodology capable of demonstrating that the architecture does achieve the predicted performance characteristics consists of a hierarchy of activities ranging from analytical calculations of system reliability and formal methods of software verification to iron bird testing followed by flight evaluation. Interfacing this architecture to the Lockheed S-3A aircraft for flight test is discussed. This testbed vehicle can be expanded to support flight experiments in advanced aerodynamics, electromechanical actuators, secondary power systems, flight management, new displays, and air traffic control concepts.

  8. Accelerating cleanup: Paths to closure

    SciTech Connect

    Edwards, C.

    1998-06-30

    This document was previously referred to as the Draft 2006 Plan. As part of the DOE`s national strategy, the Richland Operations Office`s Paths to Closure summarizes an integrated path forward for environmental cleanup at the Hanford Site. The Hanford Site underwent a concerted effort between 1994 and 1996 to accelerate the cleanup of the Site. These efforts are reflected in the current Site Baseline. This document describes the current Site Baseline and suggests strategies for further improvements in scope, schedule and cost. The Environmental Management program decided to change the name of the draft strategy and the document describing it in response to a series of stakeholder concerns, including the practicality of achieving widespread cleanup by 2006. Also, EM was concerned that calling the document a plan could be misconstrued to be a proposal by DOE or a decision-making document. The change in name, however, does not diminish the 2006 vision. To that end, Paths to Closure retains a focus on 2006, which serves as a point in time around which objectives and goals are established.

  9. Path planning under spatial uncertainty.

    PubMed

    Wiener, Jan M; Lafon, Matthieu; Berthoz, Alain

    2008-04-01

    In this article, we present experiments studying path planning under spatial uncertainties. In the main experiment, the participants' task was to navigate the shortest possible path to find an object hidden in one of four places and to bring it to the final destination. The probability of finding the object (probability matrix) was different for each of the four places and varied between conditions. Givensuch uncertainties about the object's location, planning a single path is not sufficient. Participants had to generate multiple consecutive plans (metaplans)--for example: If the object is found in A, proceed to the destination; if the object is not found, proceed to B; and so on. The optimal solution depends on the specific probability matrix. In each condition, participants learned a different probability matrix and were then asked to report the optimal metaplan. Results demonstrate effective integration of the probabilistic information about the object's location during planning. We present a hierarchical planning scheme that could account for participants' behavior, as well as for systematic errors and differences between conditions.

  10. Electron Inelastic-Mean-Free-Path Database

    National Institute of Standards and Technology Data Gateway

    SRD 71 NIST Electron Inelastic-Mean-Free-Path Database (PC database, no charge)   This database provides values of electron inelastic mean free paths (IMFPs) for use in quantitative surface analyses by AES and XPS.

  11. Time optimal paths for high speed maneuvering

    SciTech Connect

    Reister, D.B.; Lenhart, S.M.

    1993-01-01

    Recent theoretical results have completely solved the problem of determining the minimum length path for a vehicle with a minimum turning radius moving from an initial configuration to a final configuration. Time optimal paths for a constant speed vehicle are a subset of the minimum length paths. This paper uses the Pontryagin maximum principle to find time optimal paths for a constant speed vehicle. The time optimal paths consist of sequences of axes of circles and straight lines. The maximum principle introduces concepts (dual variables, bang-bang solutions, singular solutions, and transversality conditions) that provide important insight into the nature of the time optimal paths. We explore the properties of the optimal paths and present some experimental results for a mobile robot following an optimal path.

  12. Flight Project Data Book

    NASA Technical Reports Server (NTRS)

    1992-01-01

    The Office of Space Science and Applications (OSSA) is responsible for the overall planning, directing, executing, and evaluating that part of the overall NASA program that has the goal of using the unique characteristics of the space environment to conduct a scientific study of the universe, to understand how the Earth works as an integrated system, to solve practical problems on Earth, and to provide the scientific and technological research foundation for expanding human presence beyond Earth orbit into the solar system. OSSA guides its program toward leadership through its pursuit of excellence across the full spectrum of disciplines. OSSA pursues these goals through an integrated program of ground-based laboratory research and experimentation, suborbital flight of instruments on airplanes, balloons, and sounding rockets; flight of instruments and the conduct of research on the Shuttle/Spacelab system and on Space Station Freedom; and development and flight of automated Earth-orbiting and interplanetary spacecraft. The OSSA program is conducted with the participation and support of other Government agencies and facilities, universities throughout the United States, the aerospace contractor community, and all of NASA's nine Centers. In addition, OSSA operates with substantial international participation in many aspects of our Space Science and Applications Program. OSSA's programs currently in operation, those approved for development, and those planned for future missions are described.

  13. Solar array flight experiment

    NASA Technical Reports Server (NTRS)

    1986-01-01

    Emerging satellite designs require increasing amounts of electrical power to operate spacecraft instruments and to provide environments suitable for human habitation. In the past, electrical power was generated by covering rigid honeycomb panels with solar cells. This technology results in unacceptable weight and volume penalties when large amounts of power are required. To fill the need for large-area, lightweight solar arrays, a fabrication technique in which solar cells are attached to a copper printed circuit laminated to a plastic sheet was developed. The result is a flexible solar array with one-tenth the stowed volume and one-third the weight of comparably sized rigid arrays. An automated welding process developed to attack the cells to the printed circuit guarantees repeatable welds that are more tolerant of severe environments than conventional soldered connections. To demonstrate the flight readiness of this technology, the Solar Array Flight Experiment (SAFE) was developed and flown on the space shuttle Discovery in September 1984. The tests showed the modes and frequencies of the array to be very close to preflight predictions. Structural damping, however, was higher than anticipated. Electrical performance of the active solar panel was also tested. The flight performance and postflight data evaluation are described.

  14. Measurement and Characterization of Helicopter Noise in Steady-State and Maneuvering Flight

    NASA Technical Reports Server (NTRS)

    Schmitz, Fredric H.; Greenwood, Eric; Sickenberger, Richard D.; Gopalan, Gaurav; Sim, Ben Well-C; Conner, David; Moralez, Ernesto; Decker, William A.

    2007-01-01

    A special acoustic flight test program was performed on the Bell 206B helicopter outfitted with an in-flight microphone boom/array attached to the helicopter while simultaneous acoustic measurements were made using a linear ground array of microphones arranged to be perpendicular to the flight path. Air and ground noise measurements were made in steady-state longitudinal and steady turning flight, and during selected dynamic maneuvers. Special instrumentation, including direct measurement of the helicopter s longitudinal tip-path-plane (TPP) angle, Differential Global Positioning System (DGPS) and Inertial Navigation Unit (INU) measurements, and a pursuit guidance display were used to measure important noise controlling parameters and to make the task of flying precise operating conditions and flight track easier for the pilot. Special care was also made to test only in very low winds. The resulting acoustic data is of relatively high quality and shows the value of carefully monitoring and controlling the helicopter s performance state. This paper has shown experimentally, that microphones close to the helicopter can be used to estimate the specific noise sources that radiate to the far field, if the microphones are positioned correctly relative to the noise source. Directivity patterns for steady, turning flight were also developed, for the first time, and connected to the turning performance of the helicopter. Some of the acoustic benefits of combining normally separated flight segments (i.e. an accelerated segment and a descending segment) were also demonstrated.

  15. Bats coordinate sonar and flight behavior as they forage in open and cluttered environments.

    PubMed

    Falk, Benjamin; Jakobsen, Lasse; Surlykke, Annemarie; Moss, Cynthia F

    2014-12-15

    Echolocating bats use active sensing as they emit sounds and listen to the returning echoes to probe their environment for navigation, obstacle avoidance and pursuit of prey. The sensing behavior of bats includes the planning of 3D spatial trajectory paths, which are guided by echo information. In this study, we examined the relationship between active sonar sampling and flight motor output as bats changed environments from open space to an artificial forest in a laboratory flight room. Using high-speed video and audio recordings, we reconstructed and analyzed 3D flight trajectories, sonar beam aim and acoustic sonar emission patterns as the bats captured prey. We found that big brown bats adjusted their sonar call structure, temporal patterning and flight speed in response to environmental change. The sonar beam aim of the bats predicted the flight turn rate in both the open room and the forest. However, the relationship between sonar beam aim and turn rate changed in the forest during the final stage of prey pursuit, during which the bat made shallower turns. We found flight stereotypy developed over multiple days in the forest, but did not find evidence for a reduction in active sonar sampling with experience. The temporal patterning of sonar sound groups was related to path planning around obstacles in the forest. Together, these results contribute to our understanding of how bats coordinate echolocation and flight behavior to represent and navigate their environment.

  16. Bats coordinate sonar and flight behavior as they forage in open and cluttered environments

    PubMed Central

    Falk, Benjamin; Jakobsen, Lasse; Surlykke, Annemarie; Moss, Cynthia F.

    2014-01-01

    Echolocating bats use active sensing as they emit sounds and listen to the returning echoes to probe their environment for navigation, obstacle avoidance and pursuit of prey. The sensing behavior of bats includes the planning of 3D spatial trajectory paths, which are guided by echo information. In this study, we examined the relationship between active sonar sampling and flight motor output as bats changed environments from open space to an artificial forest in a laboratory flight room. Using high-speed video and audio recordings, we reconstructed and analyzed 3D flight trajectories, sonar beam aim and acoustic sonar emission patterns as the bats captured prey. We found that big brown bats adjusted their sonar call structure, temporal patterning and flight speed in response to environmental change. The sonar beam aim of the bats predicted the flight turn rate in both the open room and the forest. However, the relationship between sonar beam aim and turn rate changed in the forest during the final stage of prey pursuit, during which the bat made shallower turns. We found flight stereotypy developed over multiple days in the forest, but did not find evidence for a reduction in active sonar sampling with experience. The temporal patterning of sonar sound groups was related to path planning around obstacles in the forest. Together, these results contribute to our understanding of how bats coordinate echolocation and flight behavior to represent and navigate their environment. PMID:25394632

  17. A review of some head-up display formats. [tests on sensing equipment for flights following partly visible terrain close to the ground

    NASA Technical Reports Server (NTRS)

    Naish, J. M.

    1979-01-01

    Two alternate head-up display devices (HUD) were compared for properties relevant to the accurate performance of concurrent tasks in real flight conditions and in various flight modes. The comparisons were made to find the disorientation resistance of the HUDs along with the tracking accuracy, interference resistance, fixation resistance, and error resistance. The use of displacement and flight path information for vertical control is discussed in terms of flight stability. Several combinations of symbols and driving signals are described, including a compensated control law, which were used in simulated flight to deal with wind shear.

  18. Multiple Paths to Encephalization and Technical Civilizations

    NASA Astrophysics Data System (ADS)

    Schwartzman, David; Middendorf, George

    2011-12-01

    We propose consideration of at least two possible evolutionary paths for the emergence of intelligent life with the potential for technical civilization. The first is the path via encephalization of homeothermic animals; the second is the path to swarm intelligence of so-called superorganisms, in particular the social insects. The path to each appears to be facilitated by environmental change: homeothermic animals by decreased climatic temperature and for swarm intelligence by increased oxygen levels.

  19. Path-Based Supports for Hypergraphs

    NASA Astrophysics Data System (ADS)

    Brandes, Ulrik; Cornelsen, Sabine; Pampel, Barbara; Sallaberry, Arnaud

    A path-based support of a hypergraph H is a graph with the same vertex set as H in which each hyperedge induces a Hamiltonian subgraph. While it is NP-complete to compute a path-based support with the minimum number of edges or to decide whether there is a planar path-based support, we show that a path-based tree support can be computed in polynomial time if it exists.

  20. In-flight detection and identification and accommodation of aircraft icing

    NASA Astrophysics Data System (ADS)

    Caliskan, Fikret; Hajiyev, Chingiz

    2012-11-01

    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 paper, aircraft icing identification based on neural networks is investigated. Following icing identification, reconfigurable control is applied for protecting the aircraft from hazardous icing conditions.

  1. Analyzing the flared landing task with pitch-rate flight control systems

    NASA Technical Reports Server (NTRS)

    Hess, Ronald A.; Yousefpor, Marduke

    1990-01-01

    A closed-loop handling qualities methodology is applied to an analysis of the flared landing task with pitch-rate flight control systems. A model of pilot behavior throughout approach and flare is developed which postulates the manner in which the pilot may move from pitch attitude to flight path angle control. Twenty-five configurations flight tested on the NC-131H Total In-flight Simulator aircraft are analyzed using a structural pilot model ad a handling qualities methodology previously reported in the literature. Closed-loop simulation of the simplified landing task is undertaken using the structural model. The pilot ratings from flight test extended the data base supporting the utility of a model-based handling qualities metric. A handling qualities sensitivity function is introduced which may have potential as a design tool.

  2. Recycling Flight Hardware Components and Systems to Reduce Next Generation Research Costs

    NASA Technical Reports Server (NTRS)

    Turner, Wlat

    2011-01-01

    With the recent 'new direction' put forth by President Obama identifying NASA's new focus in research rather than continuing on a path to return to the Moon and Mars, the focus of work at Kennedy Space Center (KSC) may be changing dramatically. Research opportunities within the micro-gravity community potentially stands at the threshold of resurgence when the new direction of the agency takes hold for the next generation of experimenters. This presentation defines a strategy for recycling flight experiment components or part numbers, in order to reduce research project costs, not just in component selection and fabrication, but in expediting qualification of hardware for flight. A key component of the strategy is effective communication of relevant flight hardware information and available flight hardware components to researchers, with the goal of 'short circuiting' the design process for flight experiments

  3. Flight mechanics of a tailless articulated wing aircraft.

    PubMed

    Paranjape, Aditya A; Chung, Soon-Jo; Selig, Michael S

    2011-06-01

    This paper investigates the flight mechanics of a micro aerial vehicle without a vertical tail in an effort to reverse-engineer the agility of avian flight. The key to stability and control of such a tailless aircraft lies in the ability to control the incidence angles and dihedral angles of both wings independently. The dihedral angles can be varied symmetrically on both wings to control aircraft speed independently of the angle of attack and flight path angle, while asymmetric dihedral can be used to control yaw in the absence of a vertical stabilizer. It is shown that wing dihedral angles alone can effectively regulate sideslip during rapid turns and generate a wide range of equilibrium turn rates while maintaining a constant flight speed and regulating sideslip. Numerical continuation and bifurcation analysis are used to compute trim states and assess their stability. This paper lays the foundation for design and stability analysis of a flapping wing aircraft that can switch rapidly from flapping to gliding flight for agile manoeuvring in a constrained environment.

  4. NASA Bioculture System: From Experiment Definition to Flight Payload

    NASA Technical Reports Server (NTRS)

    Sato, Kevin Y.; Almeida, Eduardo; Austin, Edward M.

    2014-01-01

    Starting in 2015, the NASA Bioculture System will be available to the science community to conduct cell biology and microbiology experiments on ISS. The Bioculture System carries ten environmentally independent Cassettes, which house the experiments. The closed loop fluids flow path subsystem in each Cassette provides a perfusion-based method for maintain specimen cultures in a shear-free environment by using a biochamber based on porous hollow fiber bioreactor technology. Each Cassette contains an incubator and separate insulated refrigerator compartment for storage of media, samples, nutrients and additives. The hardware is capable of fully automated or manual specimen culturing and processing, including in-flight experiment initiation, sampling and fixation, up to BSL-2 specimen culturing, and the ability to up to 10 independent cultures in parallel for statistical analysis. The incubation and culturing of specimens in the Bioculture System is a departure from standard laboratory culturing methods. Therefore, it is critical that the PI has an understanding the pre-flight test required for successfully using the Bioculture System to conduct an on-orbit experiment. Overall, the PI will conduct a series of ground tests to define flight experiment and on-orbit implementation requirements, verify biocompatibility, and determine base bioreactor conditions. The ground test processes for the utilization of the Bioculture System, from experiment selection to flight, will be reviewed. Also, pre-flight test schedules and use of COTS ground test equipment (CellMax and FiberCell systems) and the Bioculture System will be discussed.

  5. Cygnus Pressurized Cargo Module (PCM) Flight Inertial Load Static Tests

    NASA Astrophysics Data System (ADS)

    Murgia, Giovanni; Mancini, Simone; Palmieri, Paolo; Rutigliano, Luigi

    2012-07-01

    Cygnus PCM Flight Inertial Load Static Test campaign has been performed by Thales Alenia Space - Italy (TAS-I) to achieve the Static Qualification of its Primary Structure. A “Proto-flight Approach” has been followed (as per [1] and [2]), thus the first flight unit, the PCM0, has been tested up to qualification level (qualification/acceptance factor equivalent to 1.2 [1]). The PCM0 has been constrained to a dummy Service Module (the second member of Cygnus Spacecraft), representative in terms of interfaces provisions, and flight load conditions have been reproduced with proper forces that have been applied by means of hydraulic jacks at internal PCM secondary structure interfaces. Test load cases have been defined in order to simulate load paths and relevant stress fields associated to the worst flight load conditions by using the FE model analyses. Tests have been monitored by means of gauges and displacement transducers and results have been utilized to correlate the PCM FEM following [3] requirements.

  6. Performance Analysis of Path Planning Modeling

    NASA Astrophysics Data System (ADS)

    Wang, Zhirui; Li, Shuanghong; Zhang, Ying; Du, Qiaoling

    Ant colony system (ACS) algorithm was applied to the path planning for the robot. In the same working environment, path planning based on MAKLINK graph theory and Voronoi diagram were simulated and compared. MAKLINK graph theory is appropriate to apply to precise searching in small-scale district, and Voronoi diagram is suitable for fast path planning in a large area.

  7. Evaluation of the Learning Path Specification

    ERIC Educational Resources Information Center

    Janssen, Jose; Berlanga, Adriana J.; Koper, Rob

    2011-01-01

    Flexible lifelong learning requires that learners can compare and select learning paths that best meet individual needs, not just in terms of learning goals, but also in terms of planning, costs etc. To this end a learning path specification was developed, which describes both the contents and the structure of any learning path, be it formal,…

  8. X-4 in flight

    NASA Technical Reports Server (NTRS)

    1951-01-01

    In the early days of transonic flight research, many aerodynamicists believed that eliminating conventional tail surfaces could reduce the problems created by shock wave interaction with the tail's lifting surfaces. To address this issue, the Army Air Forces's Air Technical Service awarded a contract to Northrop Aircraft Corporation on 5 April 1946 to build a piloted 'flying laboratory.' Northrop already had experience with tailless flying wing designs such as the N-1M, N-9M, XB-35, and YB-49. Subsequently, the manufacturer built two semi-tailless X-4 research aircraft, the first of which flew half a century ago. The X-4 was designed to investigate transonic compressibility effects at speeds near Mach 0.85 to 0.88, slightly below the speed of sound. Northrop project engineer Arthur Lusk designed the aircraft with swept wings and a conventional fuselage that housed two turbojet engines. It had a vertical stabilizer, but no horizontal tail surfaces. It was one of the smallest X-planes ever built, and every bit of internal space was used for systems and instrumentation. The first X-4 arrived at Muroc Air Force Base by truck on 15 November 1948. Over the course of several weeks, engineers conducted static tests, and Northrop test pilot Charles Tucker made initial taxi runs. Although small of stature, he barely fit into the diminutive craft. Tucker, a veteran Northrop test pilot, had previously flown the XB-35 and YB-49 flying wing bomber prototypes. Prior to flying for Northrop, he had logged 400 hours in jet airplanes as a test pilot for Lockheed and the Air Force. He would now be responsible for completing the contractor phase of the X-4 flight test program. Finally, all was ready. Tucker climbed into the cockpit, and made the first flight on 15 December 1948. It only lasted 18 minutes, allowing just enough time for the pilot to become familiar with the basic handling qualities of the craft. The X-4 handled well, but Tucker noted some longitudinal instability at all

  9. In-flight Diagnostics in LISA Pathfinder

    NASA Astrophysics Data System (ADS)

    Lobo, A.; Nofrarias, M.; Ramos-Castro, J.; Sanjuan, J.; Conchillo, A.; Ortega, J. A.; Xirgu, X.; Araujo, H.; Boatella, C.; Chmeissani, M.; Grimani, C.; Puigdengoles, C.; Wass, P.; García-Berro, E.; García, S.; Martínez, L. M.; Montero, G.

    2006-11-01

    LISA PathFinder (LPF) will be flown with the objective to test in space key technologies for LISA. However its sensitivity goals are, for good reason, one order of magnitude less than those which LISA will have to meet, both in drag-free and optical metrology requirements, and in the observation frequency band. While the expected success of LPF will of course be of itself a major step forward to LISA, one might not forget that a further improvement by an order of magnitude in performance will still be needed. Clues for the last leap are to be derived from proper disentanglement of the various sources of noise which contribute to the total noise, as measured in flight during the PathFinder mission. This paper describes the principles, workings and requirements of one of the key tools to serve the above objective: the diagnostics subsystem. This consists in sets of temperature, magnetic field, and particle counter sensors, together with generators of controlled thermal and magnetic perturbations. At least during the commissioning phase, the latter will be used to identify feed-through coefficients between diagnostics sensor readings and associated actual noise contributions. A brief progress report of the current state of development of the diagnostics subsystem will be given as well.

  10. Path Relaxation: Path Planning for a Mobile Robot.

    DTIC Science & Technology

    1984-04-01

    15213 April 1984 JUN 5 1984 Copyright © 1984 Mobile Robot Laboratory, Carnegie-Mellon University The CMU Rover has been supported at the Carnegie-Mellon...particular robot or mission. Path Relaxation is part of Fido, the vision and navigation system of the CM L Rover mol)ile robot. [29, 411 The Rover , under...their 31) positions relative to the Rover . The Rover will then move about half a meter, take a new pair of pictires, find the 40 tracked points in each of

  11. A Safe Flight Approach of the UAV in the Electrical Line Inspection

    NASA Astrophysics Data System (ADS)

    Liu, Changan; Liu, Yang; Wu, Hua; Dong, Ruifang

    2015-10-01

    In recent years, the UAV (Unmanned Aerial Vehicle) inspection for the electrical line has received increasing attentions due to the advantages of low costs, easiness to control and flexibility. The UAV can inspect the electrical tower independently and automatically by planning the flight path. But during the inspection along the path, the UAV is easily impacted by gust wind due to its light weight and small size, which always leads to the crash into the electrical tower. Thus, in this paper, a safe flight approach (SFA) is proposed to make the flight be safer during the inspection. The main contributions include: firstly, the piecewise linear interpolation method is proposed to fit the distribution curve of the electrical towers based on the GPS coordinates of the electrical towers; secondly, the no-fly zone on the both sides of the distribution curve are created, and a security distance formula (SDF) is raised to decide the width of the no-fly zone; thirdly, a gust wind formula (GWF) is proposed to improve the artificial potential field approach, which can contribute to the path planning of the UAV; finally, a flight path of the UAV can be planned using the SFA to make the UAV avoid colliding with the electric tower. The proposed approach is tested on the experiment to demonstrate its effectiveness.

  12. Diving-flight aerodynamics of a peregrine falcon (Falco peregrinus).

    PubMed

    Ponitz, Benjamin; Schmitz, Anke; Fischer, Dominik; Bleckmann, Horst; Brücker, Christoph

    2014-01-01

    This study investigates the aerodynamics of the falcon Falco peregrinus while diving. During a dive peregrines can reach velocities of more than 320 km h⁻¹. Unfortunately, in freely roaming falcons, these high velocities prohibit a precise determination of flight parameters such as velocity and acceleration as well as body shape and wing contour. Therefore, individual F. peregrinus were trained to dive in front of a vertical dam with a height of 60 m. The presence of a well-defined background allowed us to reconstruct the flight path and the body shape of the falcon during certain flight phases. Flight trajectories were obtained with a stereo high-speed camera system. In addition, body images of the falcon were taken from two perspectives with a high-resolution digital camera. The dam allowed us to match the high-resolution images obtained from the digital camera with the corresponding images taken with the high-speed cameras. Using these data we built a life-size model of F. peregrinus and used it to measure the drag and lift forces in a wind-tunnel. We compared these forces acting on the model with the data obtained from the 3-D flight path trajectory of the diving F. peregrinus. Visualizations of the flow in the wind-tunnel uncovered details of the flow structure around the falcon's body, which suggests local regions with separation of flow. High-resolution pictures of the diving peregrine indicate that feathers pop-up in the equivalent regions, where flow separation in the model falcon occurred.

  13. ISOPHOT: in-flight performance report

    NASA Astrophysics Data System (ADS)

    Lemke, Dietrich; Klaas, Ulrich; Abraham, P.; Acosta Pulido, J. A.; Castaneda, H.; Cornwall, L.; Gabriel, C.; Groezinger, Ulrich; Haas, M.; Heinrichsen, Ingolf; Herbstmeier, Uwe; Schubert, Josef; Schulz, Bernhard; Stickel, Manfred; Toth, L. V.

    1998-08-01

    The imaging photopolarimeter ISOPHOT on-board the European satellite ISO houses 144 background detectors of Si:Ga, Si:P, Ge:Ga and stressed Ge:Ga, all sampled by newly developed cold read-out electronics. There is large temporal radiation damage to most of these detectors on the daily passage through the earth's radiation belts. In addition the Ge:Ga detectors exhibit a continuous responsivity increase caused by the cosmic radiation far off the earth. Effective curing procedure shave been developed to heat out these effects. The in-flight sensitivities achieved are close to the pre-flight predictions for most channels. At 100-200 micrometers cirrus confusion is a serious limit for the detection of faint objects on large parts of the sky. The cold filter wheel carrying 56 optical elements, such as filters, apertures and polarizers, as well as the focal plane chopper, operate with high precision and very low power consumption. Due to an effective cold internal baffle system the measured near-field straylight was close to the pre- flight theoretical prediction based on APART simulations. THe sun and moon straylight at 25 and 175 micrometers was measured during several solar eclipses. Drift and transients of the detectors, non-linearities of the preamplifiers, ionizing radiation effects and a complex optical path make the photometric calibration of this instrument challenging. Because most of these effects are reproducible, a calibration accuracy of < 30 percent is already available for most photometric modes. Examples of observations, including the 175 micrometers Serendipitous Sky Survey, will highlight the capabilities of the instrument.

  14. A Flight Evaluation of the Factors which Influence the Selection of Landing Approach Speeds

    NASA Technical Reports Server (NTRS)

    Drinkwater, Fred J., III; Cooper, George E.

    1958-01-01

    The factors which influence the selection of landing approach speeds are discussed from the pilot's point of view. Concepts were developed and data were obtained during a landing approach flight investigation of a large number of jet airplane configurations which included straight-wing, swept-wing, and delta-wing airplanes as well as several applications of boundary-layer control. Since the fundamental limitation to further reductions in approach speed on most configurations appeared to be associated with the reduction in the pilot's ability to control flight path angle and airspeed, this problem forms the basis of the report. A simplified equation is presented showing the basic parameters which govern the flight path angle and airspeed changes, and pilot control techniques are discussed in relation to this equation. Attention is given to several independent aerodynamic characteristics which do not affect the flight path angle or airspeed directly but which determine to a large extent the effort and attention required of the pilot in controlling these factors during the approach. These include stall characteristics, stability about all axes, and changes in trim due to thrust adjustments. The report considers the relationship between piloting technique and all of the factors previously mentioned. A piloting technique which was found to be highly desirable for control of high-performance airplanes is described and the pilot's attitudes toward low-speed flight which bear heavily on the selection of landing approach speeds under operational conditions are discussed.

  15. Optical path control in the MAM testbed

    NASA Technical Reports Server (NTRS)

    Regehr, M. W.; Hines, B.; Holmes, B.

    2003-01-01

    Future space-based optical interferometers will require control of the optical path delay to accomplish some or all of the three objectives: balancing the optical path in the two arms to within a tolerance corresponding to the coherence length of the star light being observed, modulating the optical path in order to observe the phase of the star light interference fringe, and modulating the path length in order to reduce the effect of cyclic errors in the laser metrology system used to measure the optical path length in the two arms of the interferometer.

  16. Characterizing the Evolutionary Path(s) to Early Homo

    PubMed Central

    Schroeder, Lauren; Roseman, Charles C.; Cheverud, James M.; Ackermann, Rebecca R.

    2014-01-01

    Numerous studies suggest that the transition from Australopithecus to Homo was characterized by evolutionary innovation, resulting in the emergence and coexistence of a diversity of forms. However, the evolutionary processes necessary to drive such a transition have not been examined. Here, we apply statistical tests developed from quantitative evolutionary theory to assess whether morphological differences among late australopith and early Homo species in Africa have been shaped by natural selection. Where selection is demonstrated, we identify aspects of morphology that were most likely under selective pressure, and determine the nature (type, rate) of that selection. Results demonstrate that selection must be invoked to explain an Au. africanus—Au. sediba—Homo transition, while transitions from late australopiths to various early Homo species that exclude Au. sediba can be achieved through drift alone. Rate tests indicate that selection is largely directional, acting to rapidly differentiate these taxa. Reconstructions of patterns of directional selection needed to drive the Au. africanus—Au. sediba—Homo transition suggest that selection would have affected all regions of the skull. These results may indicate that an evolutionary path to Homo without Au. sediba is the simpler path and/or provide evidence that this pathway involved more reliance on cultural adaptations to cope with environmental change. PMID:25470780

  17. The 737 graphite composite flight spoiler flight service evaluation

    NASA Technical Reports Server (NTRS)

    Coggeshall, R. L.

    1985-01-01

    The flight service experience of 111 graphite-epoxy spoilers on 737 transport aircraft and related ground based environmental exposure of graphite-epoxy material specimens is covered. Spoilers have been installed on 28 aircraft representing seven major airlines operating throughout the world. An extended flight service evaluation program of 15 years is presently underway. As of December 1984, a total of 2,092, 155 spoiler flight hours and 2,954,814 spoiler landings had been accumulated by this fleet.

  18. Orion Pad Abort 1 Flight Test - Ground and Flight Operations

    NASA Technical Reports Server (NTRS)

    Hackenbergy, Davis L.; Hicks, Wayne

    2011-01-01

    This paper discusses the ground and flight operations aspects to the Pad Abort 1 launch. The paper details the processes used to plan all operations. The paper then discussions the difficulties of integration and testing, while detailing some of the lessons learned throughout the entire launch campaign. Flight operational aspects of the launc are covered in order to provide the listener with the full suite of operational issues encountered in preparation for the first flight test of the Orion Launch Abort System.

  19. The Laser Communications Relay and the Path to the Next Generation Near Earth Relay

    NASA Technical Reports Server (NTRS)

    Israel, David J.

    2015-01-01

    NASA Goddard Space Flight Center is currently developing the Laser Communications Relay Demonstration (LCRD) as a Path to the Next Generation Near Earth Space Communication Network. The current NASA Space Network or Tracking and Data Relay Satellite System is comprised of a constellation of Tracking and Data Relay Satellites (TDRS) in geosynchronous orbit and associated ground stations and operation centers. NASA is currently targeting a next generation of relay capability on orbit in the 2025 timeframe.

  20. Attention trees and semantic paths

    NASA Astrophysics Data System (ADS)

    Giusti, Christian; Pieroni, Goffredo G.; Pieroni, Laura

    2007-02-01

    In the last few decades several techniques for image content extraction, often based on segmentation, have been proposed. It has been suggested that under the assumption of very general image content, segmentation becomes unstable and classification becomes unreliable. According to recent psychological theories, certain image regions attract the attention of human observers more than others and, generally, the image main meaning appears concentrated in those regions. Initially, regions attracting our attention are perceived as a whole and hypotheses on their content are formulated; successively the components of those regions are carefully analyzed and a more precise interpretation is reached. It is interesting to observe that an image decomposition process performed according to these psychological visual attention theories might present advantages with respect to a traditional segmentation approach. In this paper we propose an automatic procedure generating image decomposition based on the detection of visual attention regions. A new clustering algorithm taking advantage of the Delaunay- Voronoi diagrams for achieving the decomposition target is proposed. By applying that algorithm recursively, starting from the whole image, a transformation of the image into a tree of related meaningful regions is obtained (Attention Tree). Successively, a semantic interpretation of the leaf nodes is carried out by using a structure of Neural Networks (Neural Tree) assisted by a knowledge base (Ontology Net). Starting from leaf nodes, paths toward the root node across the Attention Tree are attempted. The task of the path consists in relating the semantics of each child-parent node pair and, consequently, in merging the corresponding image regions. The relationship detected in this way between two tree nodes generates, as a result, the extension of the interpreted image area through each step of the path. The construction of several Attention Trees has been performed and partial

  1. Decomposition technique and optimal trajectories for the aeroassisted flight experiment

    NASA Technical Reports Server (NTRS)

    Miele, A.; Wang, T.; Deaton, A. W.

    1990-01-01

    An actual geosynchronous Earth orbit-to-low Earth orbit (GEO-to-LEO) transfer is considered with reference to the aeroassisted flight experiment (AFE) spacecraft, and optimal trajectories are determined by minimizing the total characteristic velocity. The optimization is performed with respect to the time history of the controls (angle of attack and angle of bank), the entry path inclination and the flight time being free. Two transfer maneuvers are considered: direct ascent (DA) to LEO and indirect ascent (IA) to LEO via parking Earth orbit (PEO). By taking into account certain assumptions, the complete system can be decoupled into two subsystems: one describing the longitudinal motion and one describing the lateral motion. The angle of attack history, the entry path inclination, and the flight time are determined via the longitudinal motion subsystem. In this subsystem, the difference between the instantaneous bank angle and a constant bank angle is minimized in the least square sense subject to the specified orbital inclination requirement. Both the angles of attack and the angle of bank are shown to be constant. This result has considerable importance in the design of nominal trajectories to be used in the guidance of AFE and aeroassisted orbital transfer (AOT) vehicles.

  2. NASA/FAA Tailplane Icing Program: Flight Test Report

    NASA Technical Reports Server (NTRS)

    Ratvasky, Thomas P.; VanZante, Judith Foss; Sim, Alex

    2000-01-01

    This report presents results from research flights that explored the characteristics of an ice-contaminated tailplane using various simulated ice shapes attached to the leading edge of the horizontal tailplane. A clean leading edge provided the baseline case, then three ice shapes were flown in order of increasing severity. Flight tests included both steady state and dynamic maneuvers. The steady state points were 1G wings level and steady heading sideslips. The primary dynamic maneuvers were pushovers to various G-levels; elevator doublets; and thrust transitions. These maneuvers were conducted for a full range of flap positions and aircraft angle of attack where possible. The analysis of this data set has clearly demonstrated the detrimental effects of ice contamination on aircraft stability and controllability. Paths to tailplane stall were revealed through parameter isolation and transition studies. These paths are (1) increasing ice shape severity, (2) increasing flap deflection, (3) high or low speeds, depending on whether the aircraft is in a steady state (high speed) or pushover maneuver (low speed), and (4) increasing thrust. The flight research effort was very comprehensive, but did not examine effects of tailplane design and location, or other aircraft geometry configuration effects. However, this effort provided the role of some of the parameters in promoting tailplane stall. The lessons learned will provide guidance to regulatory agencies, aircraft manufacturers, and operators on ice-contaminated tailplane stall in the effort to increase aviation safety and reduce the fatal accident rate.

  3. Flight assessment of an integrated DNAW helicopter pilotage display system; flight trial 'HAWKOWL'

    NASA Astrophysics Data System (ADS)

    Thorndycraft, David C.; Longman, Peter J.; Marsden, David F.; Jennings, Sion

    2007-04-01

    Military helicopter operations are often constrained by environmental conditions including low light levels and poor weather. Recent operational experience has also shown the difficulty presented by certain terrain when operating at low altitude by day and night. For example, poor visual cues when flying over featureless terrain with low scene contrast, or obscuration of vision caused by wind blown and re-circulated dust at low level (brown out). These types of conditions can result in loss of spatial awareness and loss of precise control of the aircraft. Atmospheric obscurants such as fog, cloud, rain and snow can similarly lead to hazardous situations. Day Night All Weather (DNAW) systems applied research, sponsored by UK MOD, has developed a systematic, human centred approach, to understanding and developing pilotage display systems for challenging environments. A prototype DNAW system has been developed using an incremental flight test programme, leading to the flight assessment of a fully integrated pilotage display solution, trial HAWKOWL, installed in a Sea King helicopter. The system comprises several sub-systems including; a multi-spectral sensor suite, image processing and fusion; head down and head-tracked Display Night Vision Goggles; onboard mission planning and route generation; precision navigation; dynamic flight path guidance; and conformal, task dependent, symbology. A variety of qualitative and quantitative assessment techniques have been developed and applied to determine the performance of the system and the capability it provides. This paper describes the approach taken in the design, implementation and assessment of the system and identifies key results from the flight trial.

  4. The 737 graphite composite flight spoiler flight service evaluation

    NASA Technical Reports Server (NTRS)

    Coggeshall, Randy L.

    1987-01-01

    The ninth flight service report was prepared in compliance with the requirements of Contract NAS1-11668. It covers the flight service experience of 111 graphite-epoxy spoilers on 737 transport aircraft and related ground-based environmental exposure of graphite epoxy material specimens for the period 1 Jan. 1985 through 31 Dec. 1986. Spoilers have been installed on 28 aircraft representing seven major airlines operating throughout the world. An extended flight service evaluation program of 15 years is presently underway. As of 31 Dec. 1986, a total of 3,339,608 spoiler flight-hours and 3,320,952 spoiler landings had been accumulated by this fleet.

  5. Enhanced Flight Termination System Flight Demonstration and Results

    NASA Technical Reports Server (NTRS)

    Tow, David; Arce, Dennis

    2007-01-01

    This paper discusses the methodology, requirements, tests, and implementation plan for the live demonstration of the Enhanced Flight Termination System (EFTS) using a missile program at two locations in Florida: Eglin Air Force Base (AFB) and Tyndall AFB. The demonstration included the integration of EFTS Flight Termination Receivers (FTRs) onto the missile and the integration of EFTS-program-developed transmitter assets with the mission control system at Eglin and Tyndall AFBs. The initial test stages included ground testing and captive-carry flights, followed by a launch in which EFTS was designated as the primary flight termination system for the launch.

  6. Multiple order common path spectrometer

    NASA Technical Reports Server (NTRS)

    Newbury, Amy B. (Inventor)

    2010-01-01

    The present invention relates to a dispersive spectrometer. The spectrometer allows detection of multiple orders of light on a single focal plane array by splitting the orders spatially using a dichroic assembly. A conventional dispersion mechanism such as a defraction grating disperses the light spectrally. As a result, multiple wavelength orders can be imaged on a single focal plane array of limited spectral extent, doubling (or more) the number of spectral channels as compared to a conventional spectrometer. In addition, this is achieved in a common path device.

  7. Communication path for extreme environments

    NASA Technical Reports Server (NTRS)

    Jorgensen, Charles C. (Inventor); Betts, Bradley J. (Inventor)

    2010-01-01

    Methods and systems for using one or more radio frequency identification devices (RFIDs), or other suitable signal transmitters and/or receivers, to provide a sensor information communication path, to provide location and/or spatial orientation information for an emergency service worker (ESW), to provide an ESW escape route, to indicate a direction from an ESW to an ES appliance, to provide updated information on a region or structure that presents an extreme environment (fire, hazardous fluid leak, underwater, nuclear, etc.) in which an ESW works, and to provide accumulated thermal load or thermal breakdown information on one or more locations in the region.

  8. Flight Mechanics Project

    NASA Technical Reports Server (NTRS)

    Steck, Daniel

    2009-01-01

    This report documents the generation of an outbound Earth to Moon transfer preliminary database consisting of four cases calculated twice a day for a 19 year period. The database was desired as the first step in order for NASA to rapidly generate Earth to Moon trajectories for the Constellation Program using the Mission Assessment Post Processor. The completed database was created running a flight trajectory and optimization program, called Copernicus, in batch mode with the use of newly created Matlab functions. The database is accurate and has high data resolution. The techniques and scripts developed to generate the trajectory information will also be directly used in generating a comprehensive database.

  9. The Third Flight Magnet

    NASA Technical Reports Server (NTRS)

    McGhee, R. Wayne

    1998-01-01

    A self-shielded superconducting magnet was designed for the NASA Goddard Space Flight Center Adiabatic Demagnetization Refrigerator Program. This is the third magnet built from this design. The magnets utilize Cryomagnetics' patented ultra-low current technology. The magnetic system is capable of reaching a central field of two tesla at slightly under two amperes and has a total inductance of 1068 henries. This final report details the requirements of the magnet, the specifications of the resulting magnet, the test procedures and test result data for the third magnet (Serial # C-654-M), and recommended precautions for use of the magnet.

  10. Optimal guidance with obstacle avoidance for nap-of-the-earth flight

    NASA Technical Reports Server (NTRS)

    Pekelsma, Nicholas J.

    1988-01-01

    The development of automatic guidance is discussed for helicopter Nap-of-the-Earth (NOE) and near-NOE flight. It deals with algorithm refinements relating to automated real-time flight path planning and to mission planning. With regard to path planning, it relates rotorcraft trajectory characteristics to the NOE computation scheme and addresses real-time computing issues and both ride quality issues and pilot-vehicle interfaces. The automated mission planning algorithm refinements include route optimization, automatic waypoint generation, interactive applications, and provisions for integrating the results into the real-time path planning software. A microcomputer based mission planning workstation was developed and is described. Further, the application of Defense Mapping Agency (DMA) digital terrain to both the mission planning workstation and to automatic guidance is both discussed and illustrated.

  11. On-line reentry guidance algorithm with both path and no-fly zone constraints

    NASA Astrophysics Data System (ADS)

    Zhang, Da; Liu, Lei; Wang, Yongji

    2015-12-01

    This study proposes an on-line predictor-corrector reentry guidance algorithm that satisfies path and no-fly zone constraints for hypersonic vehicles with a high lift-to-drag ratio. The proposed guidance algorithm can generate a feasible trajectory at each guidance cycle during the entry flight. In the longitudinal profile, numerical predictor-corrector approaches are used to predict the flight capability from current flight states to expected terminal states and to generate an on-line reference drag acceleration profile. The path constraints on heat rate, aerodynamic load, and dynamic pressure are implemented as a part of the predictor-corrector algorithm. A tracking control law is then designed to track the reference drag acceleration profile. In the lateral profile, a novel guidance algorithm is presented. The velocity azimuth angle error threshold and artificial potential field method are used to reduce heading error and to avoid the no-fly zone. Simulated results for nominal and dispersed cases show that the proposed guidance algorithm not only can avoid the no-fly zone but can also steer a typical entry vehicle along a feasible 3D trajectory that satisfies both terminal and path constraints.

  12. In-Flight System Identification

    NASA Technical Reports Server (NTRS)

    Morelli, Eugene A.

    1998-01-01

    A method is proposed and studied whereby the system identification cycle consisting of experiment design and data analysis can be repeatedly implemented aboard a test aircraft in real time. This adaptive in-flight system identification scheme has many advantages, including increased flight test efficiency, adaptability to dynamic characteristics that are imperfectly known a priori, in-flight improvement of data quality through iterative input design, and immediate feedback of the quality of flight test results. The technique uses equation error in the frequency domain with a recursive Fourier transform for the real time data analysis, and simple design methods employing square wave input forms to design the test inputs in flight. Simulation examples are used to demonstrate that the technique produces increasingly accurate model parameter estimates resulting from sequentially designed and implemented flight test maneuvers. The method has reasonable computational requirements, and could be implemented aboard an aircraft in real time.

  13. KC-135 winglet flight results

    NASA Technical Reports Server (NTRS)

    Montoya, L. C.

    1981-01-01

    Three KC-135 winglet configurations were flight tested for cant/incidence angles of 15 deg/-4 deg, 15 deg/-2 deg, and 0 deg/-4 deg, as well as the basic wing. The flight results for the 15 deg/-4 deg and basic wing configurations confirm the wind tunnel predicted 7% incremental decrease in total drag at cruise conditions. The 15 deg/-4 configuration flight measured wing and winglet pressure distributions, loads, stability and control, flutter, and buffet also correlate well with predicted values. The only unexpected flight results as compared with analytical predictions is a flutter speed decrease for the 0 deg/-4 deg configuration. The 15 deg/-2 deg configuration results show essentially the same incremental drag reduction as the 15 deg/-4 deg configuration; however, the flight loads are approximately 30% higher for the 15 deg/-2 deg configuration. The drag data for the 0 deg/-4 deg configuration show only a flight drag reduction.

  14. An Autonomous Flight Safety System

    NASA Technical Reports Server (NTRS)

    Bull, James B.; Lanzi, Raymond J.

    2007-01-01

    The Autonomous Flight Safety System (AFSS) being developed by NASA s Goddard Space Flight Center s Wallops Flight Facility and Kennedy Space Center has completed two successful developmental flights and is preparing for a third. AFSS has been demonstrated to be a viable architecture for implementation of a completely vehicle based system capable of protecting life and property in event of an errant vehicle by terminating the flight or initiating other actions. It is capable of replacing current human-in-the-loop systems or acting in parallel with them. AFSS is configured prior to flight in accordance with a specific rule set agreed upon by the range safety authority and the user to protect the public and assure mission success. This paper discusses the motivation for the project, describes the method of development, and presents an overview of the evolving architecture and the current status.

  15. Path integration: effect of curved path complexity and sensory system on blindfolded walking.

    PubMed

    Koutakis, Panagiotis; Mukherjee, Mukul; Vallabhajosula, Srikant; Blanke, Daniel J; Stergiou, Nicholas

    2013-02-01

    Path integration refers to the ability to integrate continuous information of the direction and distance traveled by the system relative to the origin. Previous studies have investigated path integration through blindfolded walking along simple paths such as straight line and triangles. However, limited knowledge exists regarding the role of path complexity in path integration. Moreover, little is known about how information from different sensory input systems (like vision and proprioception) contributes to accurate path integration. The purpose of the current study was to investigate how sensory information and curved path complexity affect path integration. Forty blindfolded participants had to accurately reproduce a curved path and return to the origin. They were divided into four groups that differed in the curved path, circle (simple) or figure-eight (complex), and received either visual (previously seen) or proprioceptive (previously guided) information about the path before they reproduced it. The dependent variables used were average trajectory error, walking speed, and distance traveled. The results indicated that (a) both groups that walked on a circular path and both groups that received visual information produced greater accuracy in reproducing the path. Moreover, the performance of the group that received proprioceptive information and later walked on a figure-eight path was less accurate than their corresponding circular group. The groups that had the visual information also walked faster compared to the group that had proprioceptive information. Results of the current study highlight the roles of different sensory inputs while performing blindfolded walking for path integration.

  16. Advanced flight control system study

    NASA Technical Reports Server (NTRS)

    Mcgough, J.; Moses, K.; Klafin, J. F.

    1982-01-01

    The architecture, requirements, and system elements of an ultrareliable, advanced flight control system are described. The basic criteria are functional reliability of 10 to the minus 10 power/hour of flight and only 6 month scheduled maintenance. A distributed system architecture is described, including a multiplexed communication system, reliable bus controller, the use of skewed sensor arrays, and actuator interfaces. Test bed and flight evaluation program are proposed.

  17. XB-70A in flight

    NASA Technical Reports Server (NTRS)

    1968-01-01

    The XB-70 was the world's largest experimental aircraft. Capable of flight at speeds of three times the speed of sound (2,000 miles per hour) at altitudes of 70,000 feet, the XB-70 was used to collect in-flight information for use in the design of future supersonic aircraft, military and civilian. This 23-second video clip shows the XB-70A taxiing, taking off, and in flight.

  18. Information Display System for Atypical Flight Phase

    NASA Technical Reports Server (NTRS)

    Statler, Irving C. (Inventor); Ferryman, Thomas A. (Inventor); Amidan, Brett G. (Inventor); Whitney, Paul D. (Inventor); White, Amanda M. (Inventor); Willse, Alan R. (Inventor); Cooley, Scott K. (Inventor); Jay, Joseph Griffith (Inventor); Lawrence, Robert E. (Inventor); Mosbrucker, Chris J. (Inventor); Rosenthal, Loren J. (Inventor); Lynch, Robert E. (Inventor); Chidester, Thomas R. (Inventor); Prothero, Gary L. (Inventor); Andrei, Adi (Inventor); Romanowski, Timothy P. (Inventor); Robin, Daniel E. (Inventor); Prothero, Jason W. (Inventor)

    2007-01-01

    Method and system for displaying information on one or more aircraft flights, where at least one flight is determined to have at least one atypical flight phase according to specified criteria. A flight parameter trace for an atypical phase is displayed and compared graphically with a group of traces, for the corresponding flight phase and corresponding flight parameter, for flights that do not manifest atypicality in that phase.

  19. Human Space Flight

    NASA Technical Reports Server (NTRS)

    Woolford, Barbara

    2006-01-01

    The performance of complex tasks on the International Space Station (ISS) requires significant preflight crew training commitments and frequent skill and knowledge refreshment. This report documents a recently developed just-in-time training methodology, which integrates preflight hardware familiarization and procedure training with an on-orbit CD-ROM-based skill enhancement. This just-in-time concept was used to support real-time remote expert guidance to complete medical examinations using the ISS Human Research Facility (HRF). An American md Russian ISS crewmember received 2-hours of hands on ultrasound training 8 months prior to the on-orbit ultrasound exam. A CD-ROM-based Onboard Proficiency Enhancement (OPE) interactive multimedia program consisting of memory enhancing tutorials, and skill testing exercises, was completed by the crewmember six days prior to the on-orbit ultrasound exam. The crewmember was then remotely guided through a thoracic, vascular, and echocardiographic examination by ultrasound imaging experts. Results of the CD ROM based OPE session were used to modify the instructions during a complete 35 minute real-time thoracic, cardiac, and carotid/jugular ultrasound study. Following commands from the ground-based expert, the crewmember acquired all target views and images without difficulty. The anatomical content and fidelity of ultrasound video were excellent and adequate for clinical decision-making. Complex ultrasound experiments with expert guidance were performed with high accuracy following limited pre-flight training and CD-ROM-based in-flight review, despite a 2-second communication latency.

  20. NASA - Human Space Flight

    NASA Technical Reports Server (NTRS)

    Davis, Jeffrey R.

    2006-01-01

    The presentation covers five main topical areas. The first is a description of how things work in the microgravity environment such as convection and sedimentation. The second part describes the effects of microgravity on human physiology. This is followed by a description of the hazards of space flight including the environment, the space craft, and the mission. An overview of biomedical research in space, both on shuttle and ISS is the fourth section of the presentation. The presentation concludes with a history of space flight from Ham to ISS. At CART students (11th and 12th graders from Fresno Unified and Clovis Unified) are actively involved in their education. They work in teams to research real world problems and discover original solutions. Students work on projects guided by academic instructors and business partners. They will have access to the latest technology and will be expected to expand their learning environment to include the community. They will focus their studies around a career area (Professional Sciences, Advanced Communications, Engineering and Product Development, or Global Issues).

  1. [In-flight emergencies].

    PubMed

    Jessen, Knud

    2005-10-17

    It is estimated that at least one billion passengers travel by air every year. It is predicted that this number will double in the future, including an increasing number of aged passengers. It is further estimated that for every ten million passengers, 225 acute in-flight incidents and one death will occur. Modern commercial aircraft impose certain physical and physiological stresses on passengers, due mainly to the lowered barometric pressure in the cabin during cruising. The top five in-flight incidents are vasovagal, cardiac, pulmonary, and gastrointestinal attacks and minor traumas and burns. Travel by air is, however, safe and can be tolerated by most people. Each aircraft is equipped with emergency oxygen and medical kits, the crew is trained in advanced first aid, and a link to a ground-based medical centre often exists. Ill and elderly people can have their journey specifically prepared for by communication between their physician and the medical service of the particular company, providing the best opportunity for a smooth journey.

  2. BEAM Technology Flight Demonstration

    NASA Technical Reports Server (NTRS)

    Wang, David

    2005-01-01

    As technologies advance, their growing complexity makes them harder to maintain. Detection methods for isolating and identifying impending problems are needed to balance this complexity. Through comparison of signal pairs from onboard sensors, the Beacon-based Exception Analysis For Multimissions (BEAM) algorithm can identify and help classify deviations in system operation from a data-trained statistical model. The goal of this task is to mature BEAM and validate its performance on a flying test bed. A series of F-18 flight demonstrations with BEAM monitoring engine parameters in real time was used to demonstrate in-the-field readiness. Captured F-18 and simulated F-18 engine data were used in model creation and training. The algorithm was then ported to the embedded system with a data buffering, file writing, and data-time-stamp monitoring shell to reduce the impact of embedded system faults on BEAM'S ability to correctly identify engine faults. Embedded system testing identified hardware related restrictions and contributed to iterative improvements in the code's runtime performance. The system was flown with forced engine flameouts and other pilot induced faults to simulate operation out of the norm. Successful detection of these faults, confirmed through post-flight data analysis, helped BEAM achieve TRL6.

  3. Mathematical analysis study for radar data processing and enchancement. Part 2: Modeling of propagation path errors

    NASA Technical Reports Server (NTRS)

    James, R.; Brownlow, J. D.

    1985-01-01

    A study is performed under NASA contract to evaluate data from an AN/FPS-16 radar installed for support of flight programs at Dryden Flight Research Facility of NASA Ames Research Center. The purpose of this study is to provide information necessary for improving post-flight data reduction and knowledge of accuracy of derived radar quantities. Tracking data from six flights are analyzed. Noise and bias errors in raw tracking data are determined for each of the flights. A discussion of an altitude bias error during all of the tracking missions is included. This bias error is defined by utilizing pressure altitude measurements made during survey flights. Four separate filtering methods, representative of the most widely used optimal estimation techniques for enhancement of radar tracking data, are analyzed for suitability in processing both real-time and post-mission data. Additional information regarding the radar and its measurements, including typical noise and bias errors in the range and angle measurements, is also presented. This report is in two parts. This is part 2, a discussion of the modeling of propagation path errors.

  4. Shuttle Risk Progression by Flight

    NASA Technical Reports Server (NTRS)

    Hamlin, Teri; Kahn, Joe; Thigpen, Eric; Zhu, Tony; Lo, Yohon

    2011-01-01

    Understanding the early mission risk and progression of risk as a vehicle gains insights through flight is important: . a) To the Shuttle Program to understand the impact of re-designs and operational changes on risk. . b) To new programs to understand reliability growth and first flight risk. . Estimation of Shuttle Risk Progression by flight: . a) Uses Shuttle Probabilistic Risk Assessment (SPRA) and current knowledge to calculate early vehicle risk. . b) Shows impact of major Shuttle upgrades. . c) Can be used to understand first flight risk for new programs.

  5. Tactical Night Terrain Flight Navigation

    DTIC Science & Technology

    1979-09-01

    an reverse aide It necesarmy and identify by block unmber) Terrain flight Night flight Surface nav’igation 20,. AW4~ACT ( C ~venoUa sov ero " eom a maa...were used on each test flight. The helicopter used for the low-level flights were equipped initially with a commercial radar altimeter with a single...indicator, which was later changed to a military AN/APN-209 radar altimeter with dual indicators. The second helicopter was used for command and

  6. Pathfinder: Visual Analysis of Paths in Graphs

    PubMed Central

    Partl, C.; Gratzl, S.; Streit, M.; Wassermann, A. M.; Pfister, H.; Schmalstieg, D.; Lex, A.

    2016-01-01

    The analysis of paths in graphs is highly relevant in many domains. Typically, path-related tasks are performed in node-link layouts. Unfortunately, graph layouts often do not scale to the size of many real world networks. Also, many networks are multivariate, i.e., contain rich attribute sets associated with the nodes and edges. These attributes are often critical in judging paths, but directly visualizing attributes in a graph layout exacerbates the scalability problem. In this paper, we present visual analysis solutions dedicated to path-related tasks in large and highly multivariate graphs. We show that by focusing on paths, we can address the scalability problem of multivariate graph visualization, equipping analysts with a powerful tool to explore large graphs. We introduce Pathfinder (Figure 1), a technique that provides visual methods to query paths, while considering various constraints. The resulting set of paths is visualized in both a ranked list and as a node-link diagram. For the paths in the list, we display rich attribute data associated with nodes and edges, and the node-link diagram provides topological context. The paths can be ranked based on topological properties, such as path length or average node degree, and scores derived from attribute data. Pathfinder is designed to scale to graphs with tens of thousands of nodes and edges by employing strategies such as incremental query results. We demonstrate Pathfinder's fitness for use in scenarios with data from a coauthor network and biological pathways. PMID:27942090

  7. Status of automatic guidance systems for rotorcraft in low altitude flight

    NASA Technical Reports Server (NTRS)

    Sridhar, Banavar; Cheng, Victor H. L.; Swenson, Harry N.

    1992-01-01

    Rotorcraft operating in high-threat environments fly close to the earth's surface to utilize surrounding terrain, vegetation, or man-made objects to minimize the risk of being detected by an enemy. The piloting of the rotorcraft is at best a very demanding task and the pilots need help from on-board automation tools in order to devote more time to mission-related activities. The Automated Nap-of-the-Earth (NOE) Flight Program is a cooperative NASA/Army program aimed at the development of technologies for enhancing piloted low-altitude/NOE flight path management and control through computer and sensor aiding. The long-term objective is to work towards achieving automation for aiding the pilot in NOE flight with a flight demonstration of resulting computer/sensor aiding concepts at an established course. The technology for pilot-centered NOE automation is not currently available. Success in automating NOE functions will depend on major breakthroughs in real-time flight path planning algorithms, effective methods for the pilot to interface to the automatic modes, understanding of visual images, sensor data processing/fusion, and sensor development. Our approach to developing the technologies required to solve this problem consist of the following phases: (1) algorithm development, (2) laboratory evaluation, (3) piloted ground simulation, and (4) evaluation in flight. An overview of the research in this area at NASA Ames Research Center is given.

  8. SHEFEX II Flight Instrumentation And Preparation Of Post Flight Analysis

    NASA Astrophysics Data System (ADS)

    Thiele, Thomas; Siebe, Frank; Gulhan, Ali

    2011-05-01

    A main disadvantage of modern TPS systems for re- entry vehicles is the expensive manufacturing and maintenance process due to the complex geometry of these blunt nose configurations. To reduce the costs and to improve the aerodynamic performance the German Aerospace Center (DLR) is following a different approach using TPS structures consisting of flat ceramic tiles. To test these new sharp edged TPS structures the SHEFEX I flight experiment was designed and successfully performed by DLR in 2005. To further improve the reliability of the sharp edged TPS design at even higher Mach numbers, a second flight experiment SHEFEX II will be performed in September 2011. In comparison to SHEFEX I the second flight experiment has a fully symmetrical shape and will reach a maximum Mach number of about 11. Furthermore the vehicle has an active steering system using four canards to control the flight attitude during re-entry, e.g. roll angle, angle of attack and sideslip. After a successful flight the evaluation of the flight data will be performed using a combination of numerical and experimental tools. The data will be used for the improvement of the present numerical analysis tools and to get a better understanding of the aerothermal behaviour of sharp TPS structures. This paper presents the flight instrumentation of the SHEFEX II TPS. In addition the concept of the post flight analysis is presented.

  9. B-52/Pegasus with X-43A departing on first captive flight.

    NASA Technical Reports Server (NTRS)

    2001-01-01

    The NASA X-43A hypersonic research vehicle and its Pegasus booster rocket, mounted beneath the wing of their B-52 mothership, had a successful first captive-carry flight on April 28, 2001, Basically a dress rehearsal for a subsequent free flight, the captive-carry flight kept the X-43A-and-Pegasus combination attached to the B-52's wing pylon throughout the almost two-hour mission from NASA's Dryden Flight Research Center, Edwards, Calif., over the Pacific Missile Test Range, and back to Dryden. The NASA X-43A hypersonic research vehicle and its Pegasus booster rocket, mounted beneath the wing of their B-52 mothership, had a successful first captive-carry flight on April 28, 2001, Basically a dress rehearsal for a subsequent free flight, the captive-carry flight kept the X-43A-and-Pegasus combination attached to the B-52's wing pylon throughout the almost two-hour mission from NASA's Dryden Flight Research Center, Edwards, Calif., over the Pacific Missile Test Range, and back to Dryden. After taking off from the Dryden Flight Research Center, Edwards, Calif., at 12:33 p.m. PDT, the B-52 soared off the California coast on the predetermined flight path, and returned to Dryden for a 2:19 p.m. PDT landing. Pending thorough evaluation of all flight data, this captive-carry test could lead to the first flight of the X-43A 'stack' as early as mid-May. The first free flight will be air-launched by NASA's B-52 at about 24,000 feet altitude. The booster will accelerate the X-43A to Mach 7 to approximately 95,000 feet altitude. At booster burnout, the X-43 will separate from the booster and fly under its own power on a preprogrammed flight path. The hydrogen-fueled aircraft has a wingspan of approximately 5 feet, measures 12 feet long and weighs about 2,800 pounds.

  10. B-52/Pegasus with X-43A in flight over Pacific Ocean.

    NASA Technical Reports Server (NTRS)

    2001-01-01

    The NASA X-43A hypersonic research vehicle and its Pegasus booster rocket, mounted beneath the wing of their B-52 mothership, had a successful first captive-carry flight on April 28, 2001, Basically a dress rehearsal for a subsequent free flight, the captive-carry flight kept the X-43A-and-Pegasus combination attached to the B-52's wing pylon throughout the almost two-hour mission from NASA's Dryden Flight Research Center, Edwards, Calif., over the Pacific Missile Test Range, and back to Dryden. The NASA X-43A hypersonic research vehicle and its Pegasus booster rocket, mounted beneath the wing of their B-52 mothership, had a successful first captive-carry flight on April 28, 2001, Basically a dress rehearsal for a subsequent free flight, the captive-carry flight kept the X-43A-and-Pegasus combination attached to the B-52's wing pylon throughout the almost two-hour mission from NASA's Dryden Flight Research Center, Edwards, Calif., over the Pacific Missile Test Range, and back to Dryden. After taking off from the Dryden Flight Research Center, Edwards, Calif., at 12:33 p.m. PDT, the B-52 soared off the California coast on the predetermined flight path, and returned to Dryden for a 2:19 p.m. PDT landing. Pending thorough evaluation of all flight data, this captive-carry test could lead to the first flight of the X-43A 'stack' as early as mid-May. The first free flight will be air-launched by NASA's B-52 at about 24,000 feet altitude. The booster will accelerate the X-43A to Mach 7 to approximately 95,000 feet altitude. At booster burnout, the X-43 will separate from the booster and fly under its own power on a preprogrammed flight path. The hydrogen-fueled aircraft has a wingspan of approximately 5 feet, measures 12 feet long and weighs about 2,800 pounds.

  11. Close view of B-52/Pegasus with X-43A in flight.

    NASA Technical Reports Server (NTRS)

    2001-01-01

    The NASA X-43A hypersonic research vehicle and its Pegasus booster rocket, mounted beneath the wing of their B-52 mothership, had a successful first captive-carry flight on April 28, 2001, Basically a dress rehearsal for a subsequent free flight, the captive-carry flight kept the X-43A-and-Pegasus combination attached to the B-52's wing pylon throughout the almost two-hour mission from NASA's Dryden Flight Research Center, Edwards, Calif., over the Pacific Missile Test Range, and back to Dryden. The NASA X-43A hypersonic research vehicle and its Pegasus booster rocket, mounted beneath the wing of their B-52 mothership, had a successful first captive-carry flight on April 28, 2001, Basically a dress rehearsal for a subsequent free flight, the captive-carry flight kept the X-43A-and-Pegasus combination attached to the B-52's wing pylon throughout the almost two-hour mission from NASA's Dryden Flight Research Center, Edwards, Calif., over the Pacific Missile Test Range, and back to Dryden. After taking off from the Dryden Flight Research Center, Edwards, Calif., at 12:33 p.m. PDT, the B-52 soared off the California coast on the predetermined flight path, and returned to Dryden for a 2:19 p.m. PDT landing. Pending thorough evaluation of all flight data, this captive-carry test could lead to the first flight of the X-43A 'stack' as early as mid-May. The first free flight will be air-launched by NASA's B-52 at about 24,000 feet altitude. The booster will accelerate the X-43A to Mach 7 to approximately 95,000 feet altitude. At booster burnout, the X-43 will separate from the booster and fly under its own power on a preprogrammed flight path. The hydrogen-fueled aircraft has a wingspan of approximately 5 feet, measures 12 feet long and weighs about 2,800 pounds.

  12. B-52/Pegasus with X-43A landing after first captive carry flight.

    NASA Technical Reports Server (NTRS)

    2001-01-01

    The NASA X-43A hypersonic research vehicle and its Pegasus booster rocket, mounted beneath the wing of their B-52 mothership, had a successful first captive-carry flight on April 28, 2001, Basically a dress rehearsal for a subsequent free flight, the captive-carry flight kept the X-43A-and-Pegasus combination attached to the B-52's wing pylon throughout the almost two-hour mission from NASA's Dryden Flight Research Center, Edwards, Calif., over the Pacific Missile Test Range, and back to Dryden. The NASA X-43A hypersonic research vehicle and its Pegasus booster rocket, mounted beneath the wing of their B-52 mothership, had a successful first captive-carry flight on April 28, 2001, Basically a dress rehearsal for a subsequent free flight, the captive-carry flight kept the X-43A-and-Pegasus combination attached to the B-52's wing pylon throughout the almost two-hour mission from NASA's Dryden Flight Research Center, Edwards, Calif., over the Pacific Missile Test Range, and back to Dryden. After taking off from the Dryden Flight Research Center, Edwards, Calif., at 12:33 p.m. PDT, the B-52 soared off the California coast on the predetermined flight path, and returned to Dryden for a 2:19 p.m. PDT landing. Pending thorough evaluation of all flight data, this captive-carry test could lead to the first flight of the X-43A 'stack' as early as mid-May. The first free flight will be air-launched by NASA's B-52 at about 24,000 feet altitude. The booster will accelerate the X-43A to Mach 7 to approximately 95,000 feet altitude. At booster burnout, the X-43 will separate from the booster and fly under its own power on a preprogrammed flight path. The hydrogen-fueled aircraft has a wingspan of approximately 5 feet, measures 12 feet long and weighs about 2,800 pounds.

  13. In-flight simulation study of decoupled longitudinal controls for the approach and landing of a STOL aircraft

    NASA Technical Reports Server (NTRS)

    Feinreich, B.; Seckel, E.; Ellis, D. R.

    1977-01-01

    In this decoupled concept, the natural interactions of the flight variables were suppressed, and the pilot operated a separate controller for each (fore-and-aft control column for flight path angle without speed or pitch attitude change, for example). The handling qualities of the decoupled airplane were judged to be very favorable. The precise path control led to small touchdown point dispersion along with consistently low sink rates. The decoupled control system provided significantly better flying qualities than did conventional SAS applied to the same basic airframe.

  14. Integrated assignment and path planning

    NASA Astrophysics Data System (ADS)

    Murphey, Robert A.

    2005-11-01

    A surge of interest in unmanned systems has exposed many new and challenging research problems across many fields of engineering and mathematics. These systems have the potential of transforming our society by replacing dangerous and dirty jobs with networks of moving machines. This vision is fundamentally separate from the modern view of robotics in that sophisticated behavior is realizable not by increasing individual vehicle complexity, but instead through collaborative teaming that relies on collective perception, abstraction, decision making, and manipulation. Obvious examples where collective robotics will make an impact include planetary exploration, space structure assembly, remote and undersea mining, hazardous material handling and clean-up, and search and rescue. Nonetheless, the phenomenon driving this technology trend is the increasing reliance of the US military on unmanned vehicles, specifically, aircraft. Only a few years ago, following years of resistance to the use of unmanned systems, the military and civilian leadership in the United States reversed itself and have recently demonstrated surprisingly broad acceptance of increasingly pervasive use of unmanned platforms in defense surveillance, and even attack. However, as rapidly as unmanned systems have gained acceptance, the defense research community has discovered the technical pitfalls that lie ahead, especially for operating collective groups of unmanned platforms. A great deal of talent and energy has been devoted to solving these technical problems, which tend to fall into two categories: resource allocation of vehicles to objectives, and path planning of vehicle trajectories. An extensive amount of research has been conducted in each direction, yet, surprisingly, very little work has considered the integrated problem of assignment and path planning. This dissertation presents a framework for studying integrated assignment and path planning and then moves on to suggest an exact

  15. How Constant Momentum Acceleration Decouples Energy and Space Focusing in Distance-of-Flight and Time-of-Flight Mass Spectrometries

    SciTech Connect

    Dennis, Elise; Gundlach-Graham, Alexander W.; Enke, Chris; Ray, Steven J.; Carado, Anthony J.; Barinaga, Charles J.; Koppenaal, David W.; Hieftje, Gary M.

    2013-05-01

    Time-of-flight (TOF) and distance-of-flight (DOF) mass spectrometers require means for focusing ions at the detector(s) because of initial dispersions of position and energy at the time of their acceleration. Time-of-flight mass spectrometers ordinarily employ constant energy acceleration (CEA), which creates a space-focus plane at which the initial spatial dispersion is corrected. In contrast, constant-momentum acceleration (CMA), in conjunction with an ion mirror, provides focus of the initial energy dispersion at the energy focus time for ions of all m/z at their respective positions along the flight path. With CEA, the initial energy dispersion is not simultaneously correctable as its effect on ion velocity is convoluted with that of the spatial dispersion. The initial spatial dispersion with CMA remains unchanged throughout the field-free region of the flight path, so spatial dispersion can be reduced before acceleration. Improved focus is possible when each dispersion can be addressed independently. With minor modification, a TOF mass spectrometer can be operated in CMA mode by treating the TOF detector as though it were a single element in the array of detectors that would be used in a DOF mass spectrometer. Significant improvement in mass resolution is thereby achieved, albeit over a narrow range of m/z values. In this paper, experimental and theoretical results are presented that illustrate the energy-focusing capabilities of both DOF and TOF mass spectrometry.

  16. Do birds sleep in flight?

    NASA Astrophysics Data System (ADS)

    Rattenborg, Niels C.

    2006-09-01

    The following review examines the evidence for sleep in flying birds. The daily need to sleep in most animals has led to the common belief that birds, such as the common swift ( Apus apus), which spend the night on the wing, sleep in flight. The electroencephalogram (EEG) recordings required to detect sleep in flight have not been performed, however, rendering the evidence for sleep in flight circumstantial. The neurophysiology of sleep and flight suggests that some types of sleep might be compatible with flight. As in mammals, birds exhibit two types of sleep, slow-wave sleep (SWS) and rapid eye-movement (REM) sleep. Whereas, SWS can occur in one or both brain hemispheres at a time, REM sleep only occurs bihemispherically. During unihemispheric SWS, the eye connected to the awake hemisphere remains open, a state that may allow birds to visually navigate during sleep in flight. Bihemispheric SWS may also be possible during flight when constant visual monitoring of the environment is unnecessary. Nevertheless, the reduction in muscle tone that usually accompanies REM sleep makes it unlikely that birds enter this state in flight. Upon landing, birds may need to recover the components of sleep that are incompatible with flight. Periods of undisturbed postflight recovery sleep may be essential for maintaining adaptive brain function during wakefulness. The recent miniaturization of EEG recording devices now makes it possible to measure brain activity in flight. Determining if and how birds sleep in flight will contribute to our understanding of a largely unexplored aspect of avian behavior and may also provide insight into the function of sleep.

  17. Space Shuttle flying qualities and flight control system assessment

    NASA Technical Reports Server (NTRS)

    Myers, T. T.; Mcruer, D. T.; Johnston, D. E.

    1982-01-01

    This paper reviews issues, data, and analyses relevant to the longitudinal flying qualities of the Space Shuttle in approach and landing. The manual control of attitude and path are first examined theoretically to demonstrate the unconventional nature of the Shuttle's augmented pitch and path response characteristics. The time domain pitch rate transient response criterion used for design of the Shuttle flight control system is examined in context with data from recent flying qualities experiments and operational aircraft. Questions arising from this examination are addressed through comparisons with MIL-F-8785C and other proposed flying qualities criteria which indicate potential longitudinal flying qualities problems. However, it is shown that these criteria, based largely on data from conventional aircraft, may be inappropriate for assessing the Shuttle.

  18. 49 CFR 1552.3 - Flight training.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 49 Transportation 9 2010-10-01 2010-10-01 false Flight training. 1552.3 Section 1552.3..., DEPARTMENT OF HOMELAND SECURITY CIVIL AVIATION SECURITY FLIGHT SCHOOLS Flight Training for Aliens and Other Designated Individuals § 1552.3 Flight training. This section describes the procedures a flight school...

  19. Extracting Critical Path Graphs from MPI Applications

    SciTech Connect

    Schulz, M

    2005-07-27

    The critical path is one of the fundamental runtime characteristics of a parallel program. It identifies the longest execution sequence without wait delays. In other words, the critical path is the global execution path that inflicts wait operations on other nodes without itself being stalled. Hence, it dictates the overall runtime and knowing it is important to understand an application's runtime and message behavior and to target optimizations. We have developed a toolset that identifies the critical path of MPI applications, extracts it, and then produces a graphical representation of the corresponding program execution graph to visualize it. To implement this, we intercept all MPI library calls, use the information to build the relevant subset of the execution graph, and then extract the critical path from there. We have applied our technique to several scientific benchmarks and successfully produced critical path diagrams for applications running on up to 128 processors.

  20. Sequential Path Entanglement for Quantum Metrology

    PubMed Central

    Jin, Xian-Min; Peng, Cheng-Zhi; Deng, Youjin; Barbieri, Marco; Nunn, Joshua; Walmsley, Ian A.

    2013-01-01

    Path entanglement is a key resource for quantum metrology. Using path-entangled states, the standard quantum limit can be beaten, and the Heisenberg limit can be achieved. However, the preparation and detection of such states scales unfavourably with the number of photons. Here we introduce sequential path entanglement, in which photons are distributed across distinct time bins with arbitrary separation, as a resource for quantum metrology. We demonstrate a scheme for converting polarization Greenberger-Horne-Zeilinger entanglement into sequential path entanglement. We observe the same enhanced phase resolution expected for conventional path entanglement, independent of the delay between consecutive photons. Sequential path entanglement can be prepared comparably easily from polarization entanglement, can be detected without using photon-number-resolving detectors, and enables novel applications.

  1. Counting paths with Schur transitions

    NASA Astrophysics Data System (ADS)

    Díaz, Pablo; Kemp, Garreth; Véliz-Osorio, Alvaro

    2016-10-01

    In this work we explore the structure of the branching graph of the unitary group using Schur transitions. We find that these transitions suggest a new combinatorial expression for counting paths in the branching graph. This formula, which is valid for any rank of the unitary group, reproduces known asymptotic results. We proceed to establish the general validity of this expression by a formal proof. The form of this equation strongly hints towards a quantum generalization. Thus, we introduce a notion of quantum relative dimension and subject it to the appropriate consistency tests. This new quantity finds its natural environment in the context of RCFTs and fractional statistics; where the already established notion of quantum dimension has proven to be of great physical importance.

  2. Digital flight control systems

    NASA Technical Reports Server (NTRS)

    Caglayan, A. K.; Vanlandingham, H. F.

    1977-01-01

    The design of stable feedback control laws for sampled-data systems with variable rate sampling was investigated. These types of sampled-data systems arise naturally in digital flight control systems which use digital actuators where it is desirable to decrease the number of control computer output commands in order to save wear and tear of the associated equipment. The design of aircraft control systems which are optimally tolerant of sensor and actuator failures was also studied. Detection of the failed sensor or actuator must be resolved and if the estimate of the state is used in the control law, then it is also desirable to have an estimator which will give the optimal state estimate even under the failed conditions.

  3. Flight deck engine advisor

    NASA Technical Reports Server (NTRS)

    Shontz, W. D.; Records, R. M.; Antonelli, D. R.

    1992-01-01

    The focus of this project is on alerting pilots to impending events in such a way as to provide the additional time required for the crew to make critical decisions concerning non-normal operations. The project addresses pilots' need for support in diagnosis and trend monitoring of faults as they affect decisions that must be made within the context of the current flight. Monitoring and diagnostic modules developed under the NASA Faultfinder program were restructured and enhanced using input data from an engine model and real engine fault data. Fault scenarios were prepared to support knowledge base development activities on the MONITAUR and DRAPhyS modules of Faultfinder. An analysis of the information requirements for fault management was included in each scenario. A conceptual framework was developed for systematic evaluation of the impact of context variables on pilot action alternatives as a function of event/fault combinations.

  4. The Cibola flight experiment

    SciTech Connect

    Caffrey, Michael Paul; Nelson, Anthony; Salazar, Anthony; Roussel - Dupre, Diane; Katko, Kim; Palmer, Joseph; Robinson, Scott; Wirthlin, Michael; Howes, William; Richins, Daniel

    2009-01-01

    The Cibola Flight Experiment (CFE) is an experimental small satellite carrying a reconfigurable processing instrument developed at the Los Alamos National Laboratory that demonstrates the feasibility of using FPGA-based high-performance computing for sensor processing in the space environment. The CFE satellite was launched on March 8, 2007 in low-earth orbit and has operated extremely well since its deployment. The nine Xilinx Virtex FPGAs used in the payload have been used for several high-throughput sensor processing applications and for single-event upset (SEU) monitoring and mitigation. This paper will describe the CFE system and summarize its operational results. In addition, this paper will describe the results from several SEU detection circuits that were performed on the spacecraft.

  5. Flight Operations Analysis Tool

    NASA Technical Reports Server (NTRS)

    Easter, Robert; Herrell, Linda; Pomphrey, Richard; Chase, James; Wertz Chen, Julie; Smith, Jeffrey; Carter, Rebecca

    2006-01-01

    Flight Operations Analysis Tool (FLOAT) is a computer program that partly automates the process of assessing the benefits of planning spacecraft missions to incorporate various combinations of launch vehicles and payloads. Designed primarily for use by an experienced systems engineer, FLOAT makes it possible to perform a preliminary analysis of trade-offs and costs of a proposed mission in days, whereas previously, such an analysis typically lasted months. FLOAT surveys a variety of prior missions by querying data from authoritative NASA sources pertaining to 20 to 30 mission and interface parameters that define space missions. FLOAT provides automated, flexible means for comparing the parameters to determine compatibility or the lack thereof among payloads, spacecraft, and launch vehicles, and for displaying the results of such comparisons. Sparseness, typical of the data available for analysis, does not confound this software. FLOAT effects an iterative process that identifies modifications of parameters that could render compatible an otherwise incompatible mission set.

  6. X-38 - First Flight

    NASA Technical Reports Server (NTRS)

    1997-01-01

    Reminiscent of the lifting body research flights conducted more than 30 years earlier, NASA's B-52 mothership lifts off carrying a new generation of lifting body research vehicle--the X-38. The X-38 was designed to help develop an emergency crew return vehicle for the International Space Station. NASA B-52, Tail Number 008, is an air launch carrier aircraft, 'mothership,' as well as a research aircraft platform that has been used on a variety of research projects. The aircraft, a 'B' model built in 1952 and first flown on June 11, 1955, is the oldest B-52 in flying status and has been used on some of the most significant research projects in aerospace history. Some of the significant projects supported by B-52 008 include the X-15, the lifting bodies, HiMAT (highly maneuverable aircraft technology), Pegasus, validation of parachute systems developed for the space shuttle program (solid-rocket-booster recovery system and the orbiter drag chute system), and the X-38. The B-52 served as the launch vehicle on 106 X-15 flights and flew a total of 159 captive-carry and launch missions in support of that program from June 1959 to October 1968. Information gained from the highly successful X-15 program contributed to the Mercury, Gemini, and Apollo human spaceflight programs as well as space shuttle development. Between 1966 and 1975, the B-52 served as the launch aircraft for 127 of the 144 wingless lifting body flights. In the 1970s and 1980s, the B-52 was the launch aircraft for several aircraft at what is now the Dryden Flight Research Center, Edwards, California, to study spin-stall, high-angle-of attack, and maneuvering characteristics. These included the 3/8-scale F-15/spin research vehicle (SRV), the HiMAT (Highly Maneuverable Aircraft Technology) research vehicle, and the DAST (drones for aerodynamic and structural testing). The aircraft supported the development of parachute recovery systems used to recover the space shuttle solid rocket booster casings. It also

  7. X-38 - First Flight

    NASA Technical Reports Server (NTRS)

    1997-01-01

    In a scene reminiscent of the lifting body research flights conducted more than 30 years earlier, this photo shows a close-up view of NASA's B-52 mothership as it lifts off carrying a new generation of lifting body research vehicle--the X-38. The X-38 was designed to help develop an emergency crew return vehicle for the International Space Station. NASA B-52, Tail Number 008, is an air launch carrier aircraft, 'mothership,' as well as a research aircraft platform that has been used on a variety of research projects. The aircraft, a 'B' model built in 1952 and first flown on June 11, 1955, is the oldest B-52 in flying status and has been used on some of the most significant research projects in aerospace history. Some of the significant projects supported by B-52 008 include the X-15, the lifting bodies, HiMAT (highly maneuverable aircraft technology), Pegasus, validation of parachute systems developed for the space shuttle program (solid-rocket-booster recovery system and the orbiter drag chute system), and the X-38. The B-52 served as the launch vehicle on 106 X-15 flights and flew a total of 159 captive-carry and launch missions in support of that program from June 1959 to October 1968. Information gained from the highly successful X-15 program contributed to the Mercury, Gemini, and Apollo human spaceflight programs as well as space shuttle development. Between 1966 and 1975, the B-52 served as the launch aircraft for 127 of the 144 wingless lifting body flights. In the 1970s and 1980s, the B-52 was the launch aircraft for several aircraft at what is now the Dryden Flight Research Center, Edwards, California, to study spin-stall, high-angle-of attack, and maneuvering characteristics. These included the 3/8-scale F-15/spin research vehicle (SRV), the HiMAT (Highly Maneuverable Aircraft Technology) research vehicle, and the DAST (drones for aerodynamic and structural testing). The aircraft supported the development of parachute recovery systems used to recover the

  8. Cibola flight experiment

    SciTech Connect

    Roussel-Dupre, D.; Caffrey, M. P.

    2004-01-01

    Los Alamos National Laboratory is building the Cibola Flight Experiment (CFE), a reconfigurable processor payload intended for a Low Earth Orbit system. It will survey portions of the VHF and UHF radio spectra. The experiment uses networks of reprogrammable, Field Programmable Gate Arrays (FPGAs) to process the received signals for ionospheric and lightning studies. The objective is to validate the on-orbit use of commercial, reconfigurable FPGA technology utilizing several different single-event upset mitigation schemes. It will also detect and measure impulsive events that occur in a complex background. Surrey Satellite Technology, Ltd (SSTL) is building the small host satellite, CFESat, based upon SSTL's disaster monitoring constellation (DMC) and Topsat mission satellite designs. The CFESat satellite will be launched by the Space Test Program in September 2006 on the US Air Force Evolved Expendable Launch Vehicle (EELV) using the EELV's Secondary Payload Adapter (ESPA) that allows up to six small satellites to be launched as 'piggyback' passengers with larger spacecraft.

  9. Future Flight Central

    NASA Technical Reports Server (NTRS)

    1999-01-01

    NASA 'Future Flight Central,' the world's first full-scale virtual airport control tower, opened December 13, 1999 at NASA Ames Research Center, Moffett Field, California. Constructed at a cost of $10 million, the two story facility was jointly funded by NASA and the Federal Aviation Administration (FAA). The facility is designed to test ways to solve potential air and ground traffic problems at commercial airports under realistic airport conditions and configurations. The facility provides an opportunity for airlines and airports to mitigate passenger delays by fine tuning airport hub operations, gate management, ramp movement procedures, and various other airport improvements. Twelve rear projection screens provide a seamless 360 degree high- resolution view of the airport or other screens being depicted. The imaging system, powered by supercomputers, provides a realistic view of weather conditions, enviromental and seasonal effects and the movement of up to 200 active aircraft and ground vehicles.

  10. Space flight rehabilitation.

    PubMed

    Payne, Michael W C; Williams, David R; Trudel, Guy

    2007-07-01

    The weightless environment of space imposes specific physiologic adaptations on healthy astronauts. On return to Earth, these adaptations manifest as physical impairments that necessitate a period of rehabilitation. Physiologic changes result from unloading in microgravity and highly correlate with those seen in relatively immobile terrestrial patient populations such as spinal cord, geriatric, or deconditioned bed-rest patients. Major postflight impairments requiring rehabilitation intervention include orthostatic intolerance, bone demineralization, muscular atrophy, and neurovestibular symptoms. Space agencies are preparing for extended-duration missions, including colonization of the moon and interplanetary exploration of Mars. These longer-duration flights will result in more severe and more prolonged disability, potentially beyond the point of safe return to Earth. This paper will review and discuss existing space rehabilitation plans for major postflight impairments. Evidence-based rehabilitation interventions are imperative not only to facilitate return to Earth but also to extend the safe duration of exposure to a physiologically hostile microgravity environment.

  11. Moving in a moving medium: new perspectives on flight

    PubMed Central

    Shepard, Emily L. C.; Portugal, Steven J.

    2016-01-01

    One of the defining features of the aerial environment is its variability; air is almost never still. This has profound consequences for flying animals, affecting their flight stability, speed selection, energy expenditure and choice of flight path. All these factors have important implications for the ecology of flying animals, and the ecosystems they interact with, as well as providing bio-inspiration for the development of unmanned aerial vehicles. In this introduction, we touch on the factors that drive the variability in airflows, the scales of variability and the degree to which given airflows may be predictable. We then summarize how papers in this volume advance our understanding of the sensory, biomechanical, physiological and behavioural responses of animals to air flows. Overall, this provides insight into how flying animals can be so successful in this most fickle of environments. This article is part of the themed issue ‘Moving in a moving medium: new perspectives on flight’. PMID:27528772

  12. Multi-Agent Flight Simulation with Robust Situation Generation

    NASA Technical Reports Server (NTRS)

    Johnson, Eric N.; Hansman, R. John, Jr.

    1994-01-01

    A robust situation generation architecture has been developed that generates multi-agent situations for human subjects. An implementation of this architecture was developed to support flight simulation tests of air transport cockpit systems. This system maneuvers pseudo-aircraft relative to the human subject's aircraft, generating specific situations for the subject to respond to. These pseudo-aircraft maneuver within reasonable performance constraints, interact in a realistic manner, and make pre-recorded voice radio communications. Use of this system minimizes the need for human experimenters to control the pseudo-agents and provides consistent interactions between the subject and the pseudo-agents. The achieved robustness of this system to typical variations in the subject's flight path was explored. It was found to successfully generate specific situations within the performance limitations of the subject-aircraft, pseudo-aircraft, and the script used.

  13. Conflict Probe Concepts Analysis in Support of Free Flight

    NASA Technical Reports Server (NTRS)

    Warren, Anthony W.; Schwab, Robert W.; Geels, Timothy J.; Shakarian, Arek

    1997-01-01

    This study develops an operational concept and requirements for en route Free Flight using a simulation of the Cleveland Air Route Traffic Control Center, and develops requirements for an automated conflict probe for use in the Air Traffic Control (ATC) Centers. In this paper, we present the results of simulation studies and summarize implementation concepts and infrastructure requirements to transition from the current air traffic control system to mature Free Right. The transition path to Free Flight envisioned in this paper assumes an orderly development of communications, navigation, and surveillance (CNS) technologies based on results from our simulation studies. The main purpose of this study is to provide an overall context and methodology for evaluating airborne and ground-based requirements for cooperative development of the future ATC system.

  14. Simulating flight boundary conditions for orbiter payload modal survey

    NASA Technical Reports Server (NTRS)

    Chung, Y. T.; Sernaker, M. L.; Peebles, J. H.

    1993-01-01

    An approach to simulate the characteristics of the payload/orbiter interfaces for the payload modal survey was developed. The flexure designed for this approach is required to provide adequate stiffness separation in the free and constrained interface degrees of freedom to closely resemble the flight boundary condition. Payloads will behave linearly and demonstrate similar modal effective mass distribution and load path as the flight if the flexure fixture is used for the payload modal survey. The potential non-linearities caused by the trunnion slippage during the conventional fixed base modal survey may be eliminated. Consequently, the effort to correlate the test and analysis models can be significantly reduced. An example is given to illustrate the selection and the sensitivity of the flexure stiffness. The advantages of using flexure fixtures for the modal survey and for the analytical model verification are also demonstrated.

  15. The time-of-flight wall for the HADES spectrometer

    SciTech Connect

    Agodi, C.; Bassi, A.; Bassini, R.

    1998-06-01

    In the framework of the HADES (High Acceptance DiElectron Spectrometer) collaboration the authors are developing the Time Of Flight (TOF) wall subdetector. In order to efficiently select events with e{sup +}e{sup {minus}} pairs produced in the nuclear matter, the TOF wall must be able to resolve electrons from pions up to 0.5 GeV/c and from protons up to 2 GeV/c. Because the short flight path of about 2m requires a 100--150 ps time resolution, the authors are building a granular system made of scintillator rods readout on both ends by means of photomultipliers, capable of such performance.

  16. Computer vision techniques for rotorcraft low altitude flight

    NASA Technical Reports Server (NTRS)

    Sridhar, Banavar

    1990-01-01

    Rotorcraft operating in high-threat environments fly close to the earth's surface to utilize surrounding terrain, vegetation, or manmade objects to minimize the risk of being detected by an enemy. Increasing levels of concealment are achieved by adopting different tactics during low-altitude flight. Rotorcraft employ three tactics during low-altitude flight: low-level, contour, and nap-of-the-earth (NOE). The key feature distinguishing the NOE mode from the other two modes is that the whole rotorcraft, including the main rotor, is below tree-top whenever possible. This leads to the use of lateral maneuvers for avoiding obstacles, which in fact constitutes the means for concealment. The piloting of the rotorcraft is at best a very demanding task and the pilot will need help from onboard automation tools in order to devote more time to mission-related activities. The development of an automation tool which has the potential to detect obstacles in the rotorcraft flight path, warn the crew, and interact with the guidance system to avoid detected obstacles, presents challenging problems. Research is described which applies techniques from computer vision to automation of rotorcraft navigtion. The effort emphasizes the development of a methodology for detecting the ranges to obstacles in the region of interest based on the maximum utilization of passive sensors. The range map derived from the obstacle-detection approach can be used as obstacle data for the obstacle avoidance in an automatic guidance system and as advisory display to the pilot. The lack of suitable flight imagery data presents a problem in the verification of concepts for obstacle detection. This problem is being addressed by the development of an adequate flight database and by preprocessing of currently available flight imagery. The presentation concludes with some comments on future work and how research in this area relates to the guidance of other autonomous vehicles.

  17. Adaptive nonlinear flight control

    NASA Astrophysics Data System (ADS)

    Rysdyk, Rolf Theoduor

    1998-08-01

    Research under supervision of Dr. Calise and Dr. Prasad at the Georgia Institute of Technology, School of Aerospace Engineering. has demonstrated the applicability of an adaptive controller architecture. The architecture successfully combines model inversion control with adaptive neural network (NN) compensation to cancel the inversion error. The tiltrotor aircraft provides a specifically interesting control design challenge. The tiltrotor aircraft is capable of converting from stable responsive fixed wing flight to unstable sluggish hover in helicopter configuration. It is desirable to provide the pilot with consistency in handling qualities through a conversion from fixed wing flight to hover. The linear model inversion architecture was adapted by providing frequency separation in the command filter and the error-dynamics, while not exiting the actuator modes. This design of the architecture provides for a model following setup with guaranteed performance. This in turn allowed for convenient implementation of guaranteed handling qualities. A rigorous proof of boundedness is presented making use of compact sets and the LaSalle-Yoshizawa theorem. The analysis allows for the addition of the e-modification which guarantees boundedness of the NN weights in the absence of persistent excitation. The controller is demonstrated on the Generic Tiltrotor Simulator of Bell-Textron and NASA Ames R.C. The model inversion implementation is robustified with respect to unmodeled input dynamics, by adding dynamic nonlinear damping. A proof of boundedness of signals in the system is included. The effectiveness of the robustification is also demonstrated on the XV-15 tiltrotor. The SHL Perceptron NN provides a more powerful application, based on the universal approximation property of this type of NN. The SHL NN based architecture is also robustified with the dynamic nonlinear damping. A proof of boundedness extends the SHL NN augmentation with robustness to unmodeled actuator

  18. X-1 in flight

    NASA Technical Reports Server (NTRS)

    1947-01-01

    The Bell Aircraft Corporation X-1-1 (#46-062) in flight. The shock wave pattern in the exhaust plume is visible. The X-1 series aircraft were air-launched from a modified Boeing B-29 or a B-50 Superfortress bombers. The X-1-1 was painted a bright orange by Bell Aircraft. It was thought that the aircraft would be more visable to those doing the tracking during a flight. When NACA received the airplanes they were painted white, which was an easier color to find in the skies over Muroc Air Field in California. This particular craft was nicknamed 'Glamorous Glennis' by Chuck Yeager in honor of his wife, and is now on permanent display in the Smithsonian Institution's National Air and Space Museum in Washington, DC. There were five versions of the Bell X-1 rocket-powered research aircraft that flew at the NACA High-Speed Flight Research Station, Edwards, California. The bullet-shaped X-1 aircraft were built by Bell Aircraft Corporation, Buffalo, N.Y. for the U.S. Army Air Forces (after 1947, U.S. Air Force) and the National Advisory Committee for Aeronautics (NACA). The X-1 Program was originally designated the XS-1 for EXperimental Sonic. The X-1's mission was to investigate the transonic speed range (speeds from just below to just above the speed of sound) and, if possible, to break the 'sound barrier.' Three different X-1s were built and designated: X-1-1, X-1-2 (later modified to become the X-1E), and X-1-3. The basic X-1 aircraft were flown by a large number of different pilots from 1946 to 1951. The X-1 Program not only proved that humans could go beyond the speed of sound, it reinforced the understanding that technological barriers could be overcome. The X-1s pioneered many structural and aerodynamic advances including extremely thin, yet extremely strong wing sections; supersonic fuselage configurations; control system requirements; powerplant compatibility; and cockpit environments. The X-1 aircraft were the first transonic-capable aircraft to use an all

  19. ER-2 in flight

    NASA Technical Reports Server (NTRS)

    1996-01-01

    In this film clip, we see an ER-2 on its take off roll and climb as it departs from runway 22 at Edwards AFB, California. In 1981, NASA acquired its first ER-2 aircraft. The agency obtained a second ER-2 in 1989. These airplanes replaced two Lockheed U-2 aircraft, which NASA had used to collect scientific data since 1971. The U-2, and later the ER-2, were based at the Ames Research Center, Moffett Field, California, until 1997. In 1997, the ER-2 aircraft and their operations moved to NASA Dryden Flight Research Center, Edwards, California. Since the inaugural flight for this program, August 31, 1971, NASA U-2 and ER-2 aircraft have flown more than 4,000 data missions and test flights in support of scientific research conducted by scientists from NASA, other federal agencies, states, universities, and the private sector. NASA is currently using two ER-2 Airborne Science aircraft as flying laboratories. The aircraft, based at NASA Dryden, collect information about our surroundings, including Earth resources, celestial observations, atmospheric chemistry and dynamics, and oceanic processes. The aircraft also are used for electronic sensor research and development, satellite calibration, and satellite data validation. The ER-2 is a versatile aircraft well-suited to perform multiple mission tasks. It is 30 percent larger than the U-2 with a 20 feet longer wingspan and a considerably increased payload over the older airframe. The aircraft has four large pressurized experiment compartments and a high-capacity AC/DC electrical system, permitting it to carry a variety of payloads on a single mission. The modular design of the aircraft permits rapid installation or removal of payloads to meet changing mission requirements. The ER-2 has a range beyond 3,000 miles (4800 kilometers); is capable of long flight duration and can operate at altitudes up to 70,000 feet (21.3 kilometers) if required. Operating at an altitude of 65,000 feet (19.8 kilometers) the ER-2 acquires data

  20. History of Manned Space Flight

    NASA Technical Reports Server (NTRS)

    1975-01-01

    U.S. manned space projects from Mercury Redstone 3 through Skylab 4 are briefly described including dates, flight duration, crew, and number of earth/moon orbits. The flight costs of each project are itemized. Highlights in the history of the manned space program from 1957 to February, 1974 are included.

  1. Strategy in space flight experiments

    NASA Technical Reports Server (NTRS)

    Marvin, Dean; Severns, James

    1991-01-01

    The main topics of the workshop were the evaluation of both the need for flight testing of solar array hardware and the opportunities for such testing. Spacecraft charging effects, array dynamics, cost-effectiveness, and methods of flight planning were also discussed.

  2. In-flight Medical Emergencies

    PubMed Central

    Chandra, Amit; Conry, Shauna

    2013-01-01

    Introduction: Research and data regarding in-flight medical emergencies during commercial air travel are lacking. Although volunteer medical professionals are often called upon to assist, there are no guidelines or best practices to guide their actions. This paper reviews the literature quantifying and categorizing in-flight medical incidents, discusses the unique challenges posed by the in-flight environment, evaluates the legal aspects of volunteering to provide care, and suggests an approach to managing specific conditions at 30,000 feet. Methods: We conducted a MEDLINE search using search terms relevant to aviation medical emergencies and flight physiology. The reference lists of selected articles were reviewed to identify additional studies. Results: While incidence studies were limited by data availability, syncope, gastrointestinal upset, and respiratory complaints were among the most common medical events reported. Chest pain and cardiovascular events were commonly associated with flight diversion. Conclusion: When in-flight medical emergencies occur, volunteer physicians should have knowledge about the most common in-flight medical incidents, know what is available in on-board emergency medical kits, coordinate their therapy with the flight crew and remote resources, and provide care within their scope of practice. PMID:24106549

  3. STS-80 Post Flight Presentation

    NASA Technical Reports Server (NTRS)

    1996-01-01

    The flight crew of STS-80, Cmdr. Kenneth D. Cockrell, Pilot Kent V. Rominger, Mission Specialists, Tamara E. Jernigan, Thomas D. Jones, and F. Story Musgrave give a post flight presentation of their mission. This presentation is divided into two parts first a slide presentation of still shots, and the second is a video presentation.

  4. Laminar-flow flight experiments

    NASA Technical Reports Server (NTRS)

    Wagner, Richard D.; Maddalon, Dal V.; Bartlett, D. W.; Collier, F. S., Jr.; Braslow, A. L.

    1989-01-01

    The flight testing conducted over the past 10 years in the NASA laminar-flow control (LFC) will be reviewed. The LFC program was directed towards the most challenging technology application, the high supersonic speed transport. To place these recent experiences in perspective, earlier important flight tests will first be reviewed to recall the lessons learned at that time.

  5. Aircraft flight test trajectory control

    NASA Technical Reports Server (NTRS)

    Menon, P. K. A.; Walker, R. A.

    1988-01-01

    Two design techniques for linear flight test trajectory controllers (FTTCs) are described: Eigenstructure assignment and the minimum error excitation technique. The two techniques are used to design FTTCs for an F-15 aircraft model for eight different maneuvers at thirty different flight conditions. An evaluation of the FTTCs is presented.

  6. In-Flight Aerodynamic Measurements of an Iced Horizontal Tailplane

    NASA Technical Reports Server (NTRS)

    Ratvasky, Thomas P.; VanZante, Judith Foss

    1999-01-01

    The effects of tailplane icing on aircraft dynamics and tailplane aerodynamics were investigated using, NASA's modified DHC-6 Twin Otter icing research aircraft. This flight program was a major element of the four-year NASA/FAA research program that also included icing wind tunnel testing, dry-air aerodynamic wind tunnel testing, and analytical code development. Flight tests were conducted to obtain aircraft dynamics and tailplane aerodynamics of the DHC-6 with four tailplane leading-edge configurations. These configurations included a clean (baseline) and three different artificial ice shapes. Quasi-steady and various dynamic flight maneuvers were performed over the full range of angles of attack and wing flap settings with each iced tailplane configuration. This paper presents results from the quasi-steady state flight conditions and describes the range of flow fields at the horizontal tailplane, the aeroperformance effect of various ice shapes on tailplane lift and elevator hinge moment, and suggests three paths that can lead toward ice-contaminated tailplane stall. It was found that wing, flap deflection was the most significant factor in driving the tailplane angle of attack toward alpha(tail stall). However, within a given flap setting, an increase in airspeed also drove the tailplane angle of attack toward alpha(tail stall). Moreover, increasing engine thrust setting also pushed the tailplane to critical performance limits, which resulted in premature tailplane stall.

  7. Energy requirements for space flight

    NASA Technical Reports Server (NTRS)

    Lane, Helen W.

    1992-01-01

    Both the United States and the Soviet Union perform human space research. This paper reviews data available on energy metabolism in the microgravity of space flight. The level of energy utilization in space seems to be similar to that on earth, as does energy availability. However, despite adequate intake of energy and protein and in-flight exercise, lean body mass was catabolized, as indicated by negative nitrogen balance. Metabolic studies during simulated microgravity (bed rest) and true microgravity in flight have shown changes in blood glucose, fatty acids and insulin concentrations, suggesting that energy metabolism may be altered during space flight. Future research should focus on the interactions of lean body mass, diet and exercise in space, and their roles in energy metabolism during space flight.

  8. Applications of Payload Directed Flight

    NASA Technical Reports Server (NTRS)

    Ippolito, Corey; Fladeland, Matthew M.; Yeh, Yoo Hsiu

    2009-01-01

    Next generation aviation flight control concepts require autonomous and intelligent control system architectures that close control loops directly around payload sensors in manner more integrated and cohesive that in traditional autopilot designs. Research into payload directed flight control at NASA Ames Research Center is investigating new and novel architectures that can satisfy the requirements for next generation control and automation concepts for aviation. Tighter integration between sensor and machine requires definition of specific sensor-directed control modes to tie the sensor data directly into a vehicle control structures throughout the entire control architecture, from low-level stability- and control loops, to higher level mission planning and scheduling reasoning systems. Payload directed flight systems can thus provide guidance, navigation, and control for vehicle platforms hosting a suite of onboard payload sensors. This paper outlines related research into the field of payload directed flight; and outlines requirements and operating concepts for payload directed flight systems based on identified needs from the scientific literature.'

  9. Path planning for persistent surveillance applications using fixed-wing unmanned aerial vehicles

    NASA Astrophysics Data System (ADS)

    Keller, James F.

    This thesis addresses coordinated path planning for fixed-wing Unmanned Aerial Vehicles (UAVs) engaged in persistent surveillance missions. While uniquely suited to this mission, fixed wing vehicles have maneuver constraints that can limit their performance in this role. Current technology vehicles are capable of long duration flight with a minimal acoustic footprint while carrying an array of cameras and sensors. Both military tactical and civilian safety applications can benefit from this technology. We make three main contributions: C1 A sequential path planner that generates a C 2 flight plan to persistently acquire a covering set of data over a user designated area of interest. The planner features the following innovations: • A path length abstraction that embeds kino-dynamic motion constraints to estimate feasible path length. • A Traveling Salesman-type planner to generate a covering set route based on the path length abstraction. • A smooth path generator that provides C 2 routes that satisfy user specified curvature constraints. C2 A set of algorithms to coordinate multiple UAVs, including mission commencement from arbitrary locations to the start of a coordinated mission and de-confliction of paths to avoid collisions with other vehicles and fixed obstacles. C3 A numerically robust toolbox of spline-based algorithms tailored for vehicle routing validated through flight test experiments on multiple platforms. A variety of tests and platforms are discussed. The algorithms presented are based on a technical approach with approximately equal emphasis on analysis, computation, dynamic simulation, and flight test experimentation. Our planner (C1) directly takes into account vehicle maneuverability and agility constraints that could otherwise render simple solutions infeasible. This is especially important when surveillance objectives elevate the importance of optimized paths. Researchers have developed a diverse range of solutions for persistent

  10. CO2 LIDAR measurements over a 20-km slant path

    NASA Astrophysics Data System (ADS)

    Senft, Daniel C.; Fox, Marsha J.; Gonglewski, John D.; Dowling, James A.; Highland, Ronald G.; Shilko, Michael L.

    1997-01-01

    The Air Force Phillips Laboratory conducted a series of measurements in February, May and August 1995 at the Air Force Maui Optical Station (AMOS) facility on Maui, Hawaii, to determine system requirements for an airborne long path CO(subscript 2) DIAL system. The lidar incorporates a cavity-matched mode-locked 3-J laser with the 60 cm diameter AMOS Beam Director Telescope. The one-way beam propagation path length was 21.3 km, originating at the AMOS facility on Haleakala at an altitude of 3.050 km ASL, and terminating at a target site near sea level. Both heterodyne and direct detection techniques are compared with respect to radiometric performance and signal statistics. Minimum detectable absorption levels for DIAL systems using both detection techniques and a variety of targets are estimated from long- range measurements with controlled absorbers. The signal correlation as a function of interpulse temporal separation was determined for long-range direct detection measurements. Radiometric models including system optical characteristics, beam propagation considerations, target reflectivity characteristics,a nd atmospheric effects have been developed and validated experimentally. A new receiver system is currently being fabricated and the laser transmitter is being upgraded for pulse-to-pulse wavelength agility, prior to incorporation into a C-135E airborne platform for future flight experiments.

  11. A Flexible Path for Human and Robotic Space Exploration

    NASA Technical Reports Server (NTRS)

    Korsmeyer, David J.; Landis, Robert; Merrill, Raymond Gabriel; Mazanek, Daniel D.; Falck, Robert D.; Adams, Robert B.

    2010-01-01

    During the summer of 2009, a flexible path scenario for human and robotic space exploration was developed that enables frequent, measured, and publicly notable human exploration of space beyond low-Earth orbit (LEO). The formulation of this scenario was in support of the Exploration Beyond LEO subcommittee of the Review of U.S. Human Space Flight Plans Committee that was commissioned by President Obama. Exploration mission sequences that allow humans to visit a wide number of inner solar system destinations were investigated. The scope of destinations included the Earth-Moon and Earth-Sun Lagrange points, near-Earth objects (NEOs), the Moon, and Mars and its moons. The missions examined assumed the use of Constellation Program elements along with existing launch vehicles and proposed augmentations. Additionally, robotic missions were envisioned as complements to human exploration through precursor missions, as crew emplaced scientific investigations, and as sample gathering assistants to the human crews. The focus of the flexible path approach was to gain ever-increasing operational experience through human exploration missions ranging from a few weeks to several years in duration, beginning in deep space beyond LEO and evolving to landings on the Moon and eventually Mars.

  12. General Aviation Interior Noise. Part 1; Source/Path Identification

    NASA Technical Reports Server (NTRS)

    Unruh, James F.; Till, Paul D.; Palumbo, Daniel L. (Technical Monitor)

    2002-01-01

    There were two primary objectives of the research effort reported herein. The first objective was to identify and evaluate noise source/path identification technology applicable to single engine propeller driven aircraft that can be used to identify interior noise sources originating from structure-borne engine/propeller vibration, airborne propeller transmission, airborne engine exhaust noise, and engine case radiation. The approach taken to identify the contributions of each of these possible sources was first to conduct a Principal Component Analysis (PCA) of an in-flight noise and vibration database acquired on a Cessna Model 182E aircraft. The second objective was to develop and evaluate advanced technology for noise source ranking of interior panel groups such as the aircraft windshield, instrument panel, firewall, and door/window panels within the cabin of a single engine propeller driven aircraft. The technology employed was that of Acoustic Holography (AH). AH was applied to the test aircraft by acquiring a series of in-flight microphone array measurements within the aircraft cabin and correlating the measurements via PCA. The source contributions of the various panel groups leading to the array measurements were then synthesized by solving the inverse problem using the boundary element model.

  13. Orion Exploration Flight Test Post-Flight Inspection and Analysis

    NASA Technical Reports Server (NTRS)

    Miller, J. E.; Berger, E. L.; Bohl, W. E.; Christiansen, E. L.; Davis, B. A.; Deighton, K. D.; Enriquez, P. A.; Garcia, M. A.; Hyde, J. L.; Oliveras, O. M.

    2017-01-01

    The multipurpose crew vehicle, Orion, is being designed and built for NASA to handle the rigors of crew launch, sustainment and return from scientific missions beyond Earth orbit. In this role, the Orion vehicle is meant to operate in the space environments like the naturally occurring meteoroid and the artificial orbital debris environments (MMOD) with successful atmospheric reentry at the conclusion of the flight. As a result, Orion's reentry module uses durable porous, ceramic tiles on almost thirty square meters of exposed surfaces to accomplish both of these functions. These durable, non-ablative surfaces maintain their surface profile through atmospheric reentry; thus, they preserve any surface imperfections that occur prior to atmospheric reentry. Furthermore, Orion's launch abort system includes a shroud that protects the thermal protection system while awaiting launch and during ascent. The combination of these design features and a careful pre-flight inspection to identify any manufacturing imperfections results in a high confidence that damage to the thermal protection system identified post-flight is due to the in-flight solid particle environments. These favorable design features of Orion along with the unique flight profile of the first exploration flight test of Orion (EFT-1) have yielded solid particle environment measurements that have never been obtained before this flight.

  14. Expanded study of feasibility of measuring in-flight 747/JT9D loads, performance, clearance, and thermal data

    NASA Technical Reports Server (NTRS)

    Sallee, G. P.; Martin, R. L.

    1980-01-01

    The JT9D jet engine exhibits a TSFC loss of about 1 percent in the initial 50 flight cycles of a new engine. These early losses are caused by seal-wear induced opening of running clearances in the engine gas path. The causes of this seal wear have been identified as flight induced loads which deflect the engine cases and rotors, causing the rotating blades to rub against the seal surfaces, producing permanent clearance changes. The real level of flight loads encountered during airplane acceptance testing and revenue service and the engine's response in the dynamic flight environment were investigated. The feasibility of direct measurement of these flight loads and their effects by concurrent measurement of 747/JT9D propulsion system aerodynamic and inertia loads and the critical engine clearance and performance changes during 747 flight and ground operations was evaluated. A number of technical options were examined in relation to the total estimated program cost to facilitate selection of the most cost effective option. It is concluded that a flight test program meeting the overall objective of determining the levels of aerodynamic and inertia load levels to which the engine is exposed during the initial flight acceptance test and normal flight maneuvers is feasible and desirable. A specific recommended flight test program, based on the evaluation of cost effectiveness, is defined.

  15. X-31 in flight - Mongoose Maneuver

    NASA Technical Reports Server (NTRS)

    1995-01-01

    Two X-31 Enhanced Fighter Maneuverability (EFM) demonstrators were flown at the Rockwell International facility, Palmdale, California, and the NASA Dryden Flight Research Center, Edwards, California, to obtain data that may apply to the design of highly-maneuverable next-generation fighters. The program had its first flight on October 11, 1990, in Palmdale; it ended in June 1995. The X-31 program demonstrated the value of thrust vectoring (directing engine exhaust flow) coupled with advanced flight control systems, to provide controlled flight during close-in air combat at very high angles of attack. The result of this increased maneuverability is an aircraft with a significant advantage over conventional fighters. 'Angle-of-attack' (alpha) is an engineering term to describe the angle of an aircraft body and wings relative to its actual flight path. During maneuvers, pilots often fly at extreme angles of attack -- with the nose pitched up while the aircraft continues in its original direction. This can lead to loss of control and result in the loss of the aircraft, pilot or both. Three thrust-vectoring paddles made of graphite epoxy mounted on the exhaust nozzle of the X-31 aircraft directed the exhaust flow to provide control in pitch (up and down) and yaw (right and left) to improve control. The paddles can sustain heat of up to 1,500 degrees centigrade for extended periods of time. In addition the X-31 aircraft were configured with movable forward canards and fixed aft strakes. The canards were small wing-like structures set on the wing line between the nose and the leading edge of the wing. The strakes were set on the same line between the trailing edge of the wing and the engine exhaust. Both supplied additional control in tight maneuvering situations. The X-31 research program produced technical data at high angles of attack. This information is giving engineers and aircraft designers a better understanding of aerodynamics, effectiveness of flight controls

  16. Integrated Approach to Flight Crew Training

    NASA Technical Reports Server (NTRS)

    Carroll, J. E.

    1984-01-01

    The computer based approach used by United Airlines for flight training is discussed. The human factors involved in specific aircraft accidents are addressed. Flight crew interaction and communication as they relate to training and flight safety are considered.

  17. NASA test flights with increased flight stress indices

    NASA Technical Reports Server (NTRS)

    Smith, I. S., Jr.

    1991-01-01

    This paper presents the objectives, results, and conclusions stemming from a series of six test flights conducted for the National Aeronautics and Space Administration (NASA) by the National Scientific Balloon Facility (NSBF). Results from the test flights indicate that: (1) the current two U.S. balloon films are capable of being flown at significantly increased flight stress index values; (2) payload weights less than the design minimum payload can be reliably flown without fear of structural failure due to increased circumferential stress; and (3) large and rapid decreases in payload weight can be tolerated by current balloons without structural failure.

  18. Flight testing of the Capillary Pumped Loop Flight Experiment

    NASA Technical Reports Server (NTRS)

    Butler, Dan; Ottenstein, Laura; Ku, Jentung

    1995-01-01

    The Capillary Pumped Loop Flight Experiment (CAPL) employs a passive two-phase thermal control system that uses the latent heat of vaporization of ammonia to transfer heat over long distances. CAPL was designed as a prototype of the Earth Observing System (EOS) instrument thermal control systems. The purpose of the mission was to provide validation of the system performance in micro-gravity, prior to implementation on EOS. CAPL was flown on STS-60 in February, 1994, with some unexpected results related to gravitational effects on two-phase systems. Flight test results and post flight investigations will be addressed, along with a brief description of the experiment design.

  19. Foreign technology summary of flight crucial flight control systems

    NASA Technical Reports Server (NTRS)

    Rediess, H. A.

    1984-01-01

    A survey of foreign technology in flight crucial flight controls is being conducted to provide a data base for planning future research and technology programs. Only Free World countries were surveyed, and the primary emphasis was on Western Europe because that is where the most advanced technology resides. The survey includes major contemporary systems on operational aircraft, R&D flight programs, advanced aircraft developments, and major research and technology programs. The information was collected from open literature, personal communications, and a tour of several companies, government organizations, and research laboratories in the United Kingdom, France, and the Federal Republic of Germany. A summary of the survey results to date is presented.

  20. Korean Air Lines Flight 007: Lessons from the Past and Insights for the Future

    NASA Technical Reports Server (NTRS)

    Degani, Asaf; Shafto, M. (Technical Monitor)

    2001-01-01

    The majority of the problems pilot encounter when using automated systems center around two factors: (1) the pilot has an incomplete and inadequate model of how the autopilot works; and (2) the displays and flight manuals, provided to the pilot, are inadequate for the task. The tragic accident of Korean Air Lines Flight 007, a Boeing 747 that deviated from its intended flight path, provides a compelling case-study of problems related to pilots' use of automated systems. This paper describes what had happened and exposes two types of human-automation interaction problems: (1) The pilots of KAL were not provided with adequate information about the actual behavior of the autopilot and its mode transition logic; and (2) The autopilot onboard KAL 007 did not provide adequate information to the flight crew about its active and armed modes. Both factors, according to the International Civil Aviation Organization (1993) report on the accident, contributed to the aircraft's lethal navigation error.

  1. Honeybees perform optimal scale-free searching flights when attempting to locate a food source.

    PubMed

    Reynolds, Andrew M; Smith, Alan D; Reynolds, Don R; Carreck, Norman L; Osborne, Juliet L

    2007-11-01

    The foraging strategies used by animals are key to their success in spatially and temporally heterogeneous environments. We hypothesise that when a food source at a known location ceases to be available, flying insects will exhibit search patterns that optimise the rediscovery of such resources. In order to study these searching patterns, foraging honeybees were trained to an artificial feeder that was then removed, and the subsequent flight patterns of the bees were recorded using harmonic radar. We show that the flight patterns have a scale-free (Lévy-flight) characteristic that constitutes an optimal searching strategy for the location of the feeder. It is shown that this searching strategy would remain optimal even if the implementation of the Lévy-flights was imprecise due, for example, to errors in the bees' path integration system or difficulties in responding to variable wind conditions. The implications of these findings for animal foraging in general are discussed.

  2. Flight-test measurement of the noise reduction of a jet transport delayed flap approach procedure

    NASA Technical Reports Server (NTRS)

    Foster, J. D.; Lasagna, P. L.

    1976-01-01

    A delayed flap approach procedure was flight tested using the NASA CV-990 airplane to measure and analyze the noise produced beneath the flight path. Three other types of landing approaches were also flight tested to provide a comparison of the noise reduction benefits to the delayed flap approach. The conventional type of approach was used as a baseline to compare the effectiveness of the other approaches. The decelerating approach is a variation of the delayed flap approach. A detailed comparison of the ground perceived noise generated during the approaches is presented. For this comparison, the measured noise data were normalized to compensate for variations in aircraft weight and winds that occurred during the flight tests. The data show that the reduced flap approach offers some noise reduction, while the delayed flap and decelerating approaches offer significant noise reductions over the conventional approach.

  3. Perturbative Methods in Path Integration

    NASA Astrophysics Data System (ADS)

    Johnson-Freyd, Theodore Paul

    This dissertation addresses a number of related questions concerning perturbative "path" integrals. Perturbative methods are one of the few successful ways physicists have worked with (or even defined) these infinite-dimensional integrals, and it is important as mathematicians to check that they are correct. Chapter 0 provides a detailed introduction. We take a classical approach to path integrals in Chapter 1. Following standard arguments, we posit a Feynman-diagrammatic description of the asymptotics of the time-evolution operator for the quantum mechanics of a charged particle moving nonrelativistically through a curved manifold under the influence of an external electromagnetic field. We check that our sum of Feynman diagrams has all desired properties: it is coordinate-independent and well-defined without ultraviolet divergences, it satisfies the correct composition law, and it satisfies Schrodinger's equation thought of as a boundary-value problem in PDE. Path integrals in quantum mechanics and elsewhere in quantum field theory are almost always of the shape ∫ f es for some functions f (the "observable") and s (the "action"). In Chapter 2 we step back to analyze integrals of this type more generally. Integration by parts provides algebraic relations between the values of ∫ (-) es for different inputs, which can be packaged into a Batalin--Vilkovisky-type chain complex. Using some simple homological perturbation theory, we study the version of this complex that arises when f and s are taken to be polynomial functions, and power series are banished. We find that in such cases, the entire scheme-theoretic critical locus (complex points included) of s plays an important role, and that one can uniformly (but noncanonically) integrate out in a purely algebraic way the contributions to the integral from all "higher modes," reducing ∫ f es to an integral over the critical locus. This may help explain the presence of analytic continuation in questions like the

  4. Current Simulator Substitution Practices in Flight Training

    DTIC Science & Technology

    1977-02-01

    environments. The percentage reduction of the original in-flight syllabus (effectiveness) and the ratio of simulator hours required per in-flight...in the report are percent flight TAEG Report No. 43 syllabus reduction and flight substitution ratio. Explanatory information is provided to...formula (Percent Flight Syllabus Reduction) expresses the overall ability of the simulator to reduce the amount of in-flight training in the syllabus

  5. IVGEN Post Flight Analysis

    NASA Technical Reports Server (NTRS)

    Mcquillen, John; Brown, Dan; Hussey, Sam; Zoldak, John

    2014-01-01

    The Intravenous Fluid Generation (IVGEN) Experiment was a technology demonstration experiment that purified ISS potable water, mixed it with salt, and transferred it through a sterilizing filter. On-orbit performance was verified as appropriate and two 1.5 l bags of normal saline solution were returned to earth for post-flight testing by a FDA certified laboratory for compliance with United States Pharmacopiea (USP) standards. Salt concentration deviated from required values and an analysis identified probable causes. Current efforts are focused on Total Organic Content (TOC) testing, and shelf life.The Intravenous Fluid Generation (IVGEN) Experiment demonstrated the purification of ISS potable water, the mixing of the purified water with sodium chloride, and sterilization of the solution via membrane filtration. On-orbit performance was monitored where feasible and two 1.5-liter bags of normal saline solution were returned to earth for post-flight testing by a FDA-registered laboratory for compliance with United States Pharmacopeia (USP)standards [1]. Current efforts have been focused on challenge testing with identified [2] impurities (total organic-carbon), and shelf life testing. The challenge testing flowed known concentrations of contaminants through the IVGEN deionizing cartridge and membrane filters to test their effectiveness. One finding was that the filters and DI-resin themselves contribute to the contaminant load during initial startup, suggesting that the first 100 ml of fluid be discarded. Shelf life testing is ongoing and involves periodic testing of stored DI cartridges and membrane filters that are capped and sealed in hermetic packages. The testing is conducted at six month intervals measuring conductivity and endotoxins in the effluent. Currently, the packaging technique has been successfully demonstrated for one year of storage testing. The USP standards specifies that the TOC be conducted at point of generation as opposed to point of

  6. In-flight corrections in free-flying barn owls (Tyto alba) during sound localization tasks.

    PubMed

    Hausmann, Laura; Plachta, Dennis T T; Singheiser, Martin; Brill, Sandra; Wagner, Hermann

    2008-09-01

    Barn owls localize a stationary auditory target with high accuracy. They might also be able to hit a target that is intermittently moving while the owl is approaching. If so, there should be a critical delay before strike initiation, up to which the owl can adapt its flight path to a new stimulus position. In this study, this critical stimulus delay was determined in a three-dimensional free-flight paradigm. Barn owls localized a pulsed broadband noise while sitting on a perch in total darkness. This initial signal stopped with the owl's take-off and an in-flight stimulus (target sound), lasting 200 ms, was introduced at variable time delays (300-1200 ms) during the approximate flight time of 1300 ms. The owls responded to the in-flight signal with a corrective head and body turn. The percentage of trials in which correction turns occurred (40-80%) depended upon the individual bird, but was independent of the stimulus delay within a range of 800 ms after take-off. Correction turns strongly decreased at delays >or=800 ms. The landing precision of the owls, defined as their distance to the in-flight speaker, did not decrease with increasing stimulus delay, but decreased if the owl failed to perform a correction turn towards that speaker. Landing precision was higher for a short (50 cm) than for a large (100 cm) distance between the initial and the new target. Thus, the ability of barn owls to adapt their flight path to a new sound target depends on the in-flight stimulus delay, as well as on the distance between initial and novel targets.

  7. Flight Tests Validate Collision-Avoidance System

    NASA Video Gallery

    Flights tests of a smartphone-assisted automatic ground collision avoidance system at NASA's Dryden Flight Research Center consistently commanded evasive maneuvers when it sensed that the unmanned ...

  8. Uncertainty of in-flight thrust determination

    NASA Technical Reports Server (NTRS)

    Abernethy, Robert B.; Adams, Gary R.; Steurer, John W.; Ascough, John C.; Baer-Riedhart, Jennifer L.; Balkcom, George H.; Biesiadny, Thomas

    1986-01-01

    Methods for estimating the measurement error or uncertainty of in-flight thrust determination in aircraft employing conventional turbofan/turbojet engines are reviewed. While the term 'in-flight thrust determination' is used synonymously with 'in-flight thrust measurement', in-flight thrust is not directly measured but is determined or calculated using mathematical modeling relationships between in-flight thrust and various direct measurements of physical quantities. The in-flight thrust determination process incorporates both ground testing and flight testing. The present text is divided into the following categories: measurement uncertainty methodoogy and in-flight thrust measurent processes.

  9. Nutritional Biochemistry of Space Flight

    NASA Technical Reports Server (NTRS)

    Smith, Scott M.

    2000-01-01

    Adequate nutrition is critical for maintenance of crew health during and after extended-duration space flight. The impact of weightlessness on human physiology is profound, with effects on many systems related to nutrition, including bone, muscle, hematology, fluid and electrolyte regulation. Additionally, we have much to learn regarding the impact of weightlessness on absorption, mtabolism , and excretion of nutrients, and this will ultimately determine the nutrient requirements for extended-duration space flight. Existing nutritional requirements for extended-duration space flight have been formulated based on limited flight research, and extrapolation from ground-based research. NASA's Nutritional Biochemistry Laboratory is charged with defining the nutritional requirements for space flight. This is accomplished through both operational and research projects. A nutritional status assessment program is included operationally for all International Space Station astronauts. This medical requirement includes biochemical and dietary assessments, and is completed before, during, and after the missions. This program will provide information about crew health and nutritional status, and will also provide assessments of countermeasure efficacy. Ongoing research projects include studies of calcium and bone metabolism, and iron absorption and metabolism. The calcium studies include measurements of endocrine regulation of calcium homeostasis, biochemical marker of bone metabolism, and tracer kinetic studies of calcium movement in the body. These calcium kinetic studies allow for estimation of intestinal absorption, urinary excretion, and perhaps most importantly - deposition and resorption of calcium from bone. The Calcium Kinetics experiment is currently being prepared for flight on the Space Shuttle in 2001, and potentially for subsequent Shuttle and International Space Station missions. The iron study is intended to assess whether iron absorption is down-regulated dUl1ng

  10. White Noise Path Integrals in Stochastic Neurodynamics

    NASA Astrophysics Data System (ADS)

    Carpio-Bernido, M. Victoria; Bernido, Christopher C.

    2008-06-01

    The white noise path integral approach is used in stochastic modeling of neural activity, where the primary dynamical variables are the relative membrane potentials, while information on transmembrane ionic currents is contained in the drift coefficient. The white noise path integral allows a natural framework and can be evaluated explicitly to yield a closed form for the conditional probability density.

  11. The Path of Carbon in Photosynthesis VI.

    DOE R&D Accomplishments Database

    Calvin, M.

    1949-06-30

    This paper is a compilation of the essential results of our experimental work in the determination of the path of carbon in photosynthesis. There are discussions of the dark fixation of photosynthesis and methods of separation and identification including paper chromatography and radioautography. The definition of the path of carbon in photosynthesis by the distribution of radioactivity within the compounds is described.

  12. The path dependence of deformation texture development

    SciTech Connect

    Takeshita, T.; Kocks, U.F.; Wenk, H.R.

    1987-01-01

    It is demonstrated for the case of three different strain paths, all of which end up with the same, elongated specimen shape, that the texture developed during straining is path dependent. This is true both for experiments on aluminum polycrystals and for simulations using the LApp code.

  13. Career Path Guide for Adult Career Choices.

    ERIC Educational Resources Information Center

    Case, Clydia

    Intended for adults who are considering career choices or changes, this booklet provides opportunities for self-study and reflection in six career paths. The booklet begins with tips for long-term career survival and myths and realities of career planning. After a brief career survey, readers are introduced to six career paths: arts and…

  14. A Random Walk on a Circular Path

    ERIC Educational Resources Information Center

    Ching, W.-K.; Lee, M. S.

    2005-01-01

    This short note introduces an interesting random walk on a circular path with cards of numbers. By using high school probability theory, it is proved that under some assumptions on the number of cards, the probability that a walker will return to a fixed position will tend to one as the length of the circular path tends to infinity.

  15. Cooperative organic mine avoidance path planning

    NASA Astrophysics Data System (ADS)

    McCubbin, Christopher B.; Piatko, Christine D.; Peterson, Adam V.; Donnald, Creighton R.; Cohen, David

    2005-06-01

    The JHU/APL Path Planning team has developed path planning techniques to look for paths that balance the utility and risk associated with different routes through a minefield. Extending on previous years' efforts, we investigated real-world Naval mine avoidance requirements and developed a tactical decision aid (TDA) that satisfies those requirements. APL has developed new mine path planning techniques using graph based and genetic algorithms which quickly produce near-minimum risk paths for complicated fitness functions incorporating risk, path length, ship kinematics, and naval doctrine. The TDA user interface, a Java Swing application that obtains data via Corba interfaces to path planning databases, allows the operator to explore a fusion of historic and in situ mine field data, control the path planner, and display the planning results. To provide a context for the minefield data, the user interface also renders data from the Digital Nautical Chart database, a database created by the National Geospatial-Intelligence Agency containing charts of the world's ports and coastal regions. This TDA has been developed in conjunction with the COMID (Cooperative Organic Mine Defense) system. This paper presents a description of the algorithms, architecture, and application produced.

  16. Adaptively Ubiquitous Learning in Campus Math Path

    ERIC Educational Resources Information Center

    Shih, Shu-Chuan; Kuo, Bor-Chen; Liu, Yu-Lung

    2012-01-01

    The purposes of this study are to develop and evaluate the instructional model and learning system which integrate ubiquitous learning, computerized adaptive diagnostic testing system and campus math path learning. The researcher first creates a ubiquitous learning environment which is called "adaptive U-learning math path system". This…

  17. Connections on decorated path space bundles

    NASA Astrophysics Data System (ADS)

    Chatterjee, Saikat; Lahiri, Amitabha; Sengupta, Ambar N.

    2017-02-01

    For a principal bundle P → M equipped with a connection A ¯ , we study an infinite dimensional bundle PA¯ dec P over the space of paths on M, with the points of PA¯ dec P being horizontal paths on P decorated with elements of a second structure group. We construct parallel transport processes on such bundles and study holonomy bundles in this setting.

  18. Evaluation of Calcine Disposition - Path Forward

    SciTech Connect

    Steve Birrer

    2003-02-01

    This document describes an evaluation of the baseline and two alternative disposition paths for the final disposition of the calcine wastes stored at the Idaho Nuclear Technology and Engineering Center at the Idaho National Engineering and Environmental Laboratory. The pathways are evaluated against a prescribed set of criteria and a recommendation is made for the path forward.

  19. Modeling pilot interaction with automated digital avionics systems: Guidance and control algorithms for contour and nap-of-the-Earth flight

    NASA Technical Reports Server (NTRS)

    Hess, Ronald A.

    1990-01-01

    A collection of technical papers are presented that cover modeling pilot interaction with automated digital avionics systems and guidance and control algorithms for contour and nap-of-the-earth flight. The titles of the papers presented are as follows: (1) Automation effects in a multiloop manual control system; (2) A qualitative model of human interaction with complex dynamic systems; (3) Generalized predictive control of dynamic systems; (4) An application of generalized predictive control to rotorcraft terrain-following flight; (5) Self-tuning generalized predictive control applied to terrain-following flight; and (6) Precise flight path control using a predictive algorithm.

  20. Space Flight Immunodeficiency

    NASA Technical Reports Server (NTRS)

    Shearer, William T.

    1999-01-01

    The National Aeronautics and Space Administration (NASA) has had sufficient concern for the well-being of astronauts traveling in space to create the National Space Biomedical Research Institute (NSBRI), which is investigating several areas of biomedical research including those of immunology. As part of the Immunology, Infection, and Hematology Team, the co-investigators of the Space Flight Immunodeficiency Project began their research projects on April 1, 1998 and are now just into the second year of work. Two areas of research have been targeted: 1) specific immune (especially antibody) responses and 2) non-specific inflammation and adhesion. More precise knowledge of these two areas of research will help elucidate the potential harmful effects of space travel on the immune system, possibly sufficient to create a secondary state of immunodeficiency in astronauts. The results of these experiments are likely to lead to the delineation of functional alterations in antigen presentation, specific immune memory, cytokine regulation of immune responses, cell to cell interactions, and cell to endothelium interactions.

  1. SR-71 flight

    NASA Technical Reports Server (NTRS)

    1990-01-01

    The movie clip shown here runs about 13 seconds and shows an air-to-air shot of the front of the SR-71 aircraft and a head-on view of it coming in for a landing. Two SR-71A aircraft on loan from the U.S. Air Force have been used for high-speed, high-altitude research at the NASA Dryden Flight Research Center, Edwards, California, since 1991. One of them was later returned to the Air Force. A third SR-71 on loan from the Air Force is an SR-71B used for training but not for flight research. Developed for the U.S. Air Force as reconnaissance aircraft more than 30 years ago, SR-71 aircraft are still the world's fastest and highest-flying production aircraft. These aircraft can fly more than 2200 miles per hour (Mach 3+ or more than three times the speed of sound) and at altitudes of over 85,000 feet. This operating environment makes the aircraft excellent platforms to carry out research and experiments in a variety of areas--aerodynamics, propulsion, structures, thermal protection materials, high-speed and high-temperature instrumentation, atmospheric studies, and sonic-boom characterization. Data from the SR-71 high-speed research program may be used to aid designers of future supersonic or hypersonic aircraft and propulsion systems, including a possible high-speed civil transport. The SR-71 program at Dryden has been part of the NASA overall high-speed aeronautical research program, and projects have involved other NASA research centers, other government agencies, universities, and commercial firms. One of the first major experiments to be flown in the NASA SR-71 program was a laser air-data collection system. This system used laser light instead of air pressure to produce airspeed and attitude reference data such as angle of attack and angle of sideslip. These data are normally obtained with small tubes and vanes extending into the air stream, or from tubes with flush openings on the aircraft outer skin. The flights provided information on the presence of

  2. Gerbertian paths for the Jubilee

    NASA Astrophysics Data System (ADS)

    Sigismondi, Costantino

    2015-04-01

    Gerbert before becoming Pope Sylvester II came several times in Rome, as reported in his Letters and in the biography of Richerus. Eight places in Rome can be connected with Gerbertian memories. 1. The Cathedral of St. John in the Lateran where the gravestone of his tumb is still preserved near the Holy Door; 2. the “Basilica Hierusalem” (Santa Croce) where Gerbert had the stroke on May 3rd 1003 which lead him to death on May 12th; 3. the Aventine hill, with the church of the Knights of Malta in the place where the palace of the Ottonian Emperors was located; 4. the church of St. Bartholomew in the Tiber Island built in 997 under Otto III; 5. the Obelisk of Augustus in Montecitorio to remember the relationship between Gerbert, Astronomy and numbers which led the birth of the legends on Gerbert magician; 6. St. Mary Major end of the procession of August 15, 1000; 7. St. Paul outside the walls with the iconography of the Popes and 8. St. Peter's tumb end of all Romaei pilgrimages. This Gerbertian path in Rome suggests one way to accomplish the pilgrimage suggested by Pope Francis in the Bulla Misericordiae Vultus (14) of indiction of the new Jubilee.

  3. Bergman Kernel from Path Integral

    NASA Astrophysics Data System (ADS)

    Douglas, Michael R.; Klevtsov, Semyon

    2010-01-01

    We rederive the expansion of the Bergman kernel on Kähler manifolds developed by Tian, Yau, Zelditch, Lu and Catlin, using path integral and perturbation theory, and generalize it to supersymmetric quantum mechanics. One physics interpretation of this result is as an expansion of the projector of wave functions on the lowest Landau level, in the special case that the magnetic field is proportional to the Kähler form. This is relevant for the quantum Hall effect in curved space, and for its higher dimensional generalizations. Other applications include the theory of coherent states, the study of balanced metrics, noncommutative field theory, and a conjecture on metrics in black hole backgrounds discussed in [24]. We give a short overview of these various topics. From a conceptual point of view, this expansion is noteworthy as it is a geometric expansion, somewhat similar to the DeWitt-Seeley-Gilkey et al short time expansion for the heat kernel, but in this case describing the long time limit, without depending on supersymmetry.

  4. Decision paths in complex tasks

    NASA Technical Reports Server (NTRS)

    Galanter, Eugene

    1991-01-01

    Complex real world action and its prediction and control has escaped analysis by the classical methods of psychological research. The reason is that psychologists have no procedures to parse complex tasks into their constituents. Where such a division can be made, based say on expert judgment, there is no natural scale to measure the positive or negative values of the components. Even if we could assign numbers to task parts, we lack rules i.e., a theory, to combine them into a total task representation. We compare here two plausible theories for the amalgamation of the value of task components. Both of these theories require a numerical representation of motivation, for motivation is the primary variable that guides choice and action in well-learned tasks. We address this problem of motivational quantification and performance prediction by developing psychophysical scales of the desireability or aversiveness of task components based on utility scaling methods (Galanter 1990). We modify methods used originally to scale sensory magnitudes (Stevens and Galanter 1957), and that have been applied recently to the measure of task 'workload' by Gopher and Braune (1984). Our modification uses utility comparison scaling techniques which avoid the unnecessary assumptions made by Gopher and Braune. Formula for the utility of complex tasks based on the theoretical models are used to predict decision and choice of alternate paths to the same goal.

  5. Dynamic Flight Envelope Assessment with Flight Safety Applications

    NASA Astrophysics Data System (ADS)

    Pandita, Rohit

    Aircraft have a manufacturer prescribed operating flight envelope for safe operation, exceeding these limits can result in unrecoverable departures or even structural failure. Numerous commercial aircraft accidents in the past have been attributed to loss-of-control (LOC) resulting from exceeding the safe operating flight envelope. Hence, real-time knowledge of the safe operating flight envelope is essential for safe flight operation, a problem known as dynamic flight envelope assessment. This dissertation explores dynamic flight envelope assessment from a control theoretic perspective. Two notions of the flight envelope, namely, the reachable sets and the region-of-attraction analysis are investigated. The NASA generic transport model (GTM) aircraft dynamics is used as an application problem. Linear and nonlinear techniques for flight envelope assessment are formulated in the linear matrix inequality (LMI) and sum-of-squares (SOS) framework, respectively. LMI and SOS problems are computationally tractable convex optimization problems for which many semi-definite programming solvers are available. This thesis also investigated fault detection and isolation strategies. Commercial jet transport aircrafts make extensive use of active controls. Faults or failures in the flight control system (FCS) elements like sensors or control effectors can lead to catastrophic failure. Model-based fault detection and isolation (FDI) filters can provide analytical redundancy by reliably detecting such faults in the system. Practical application of model-based FDI filters is limited so far due to poor performance, false alarms and missed detection arising out of uncertain dynamics of the aircraft, effect of nonlinearities in the system and the influence of closed-loop controllers. An application of closed-loop metrics to assess worst case FDI filter performance in the presence of a controller and uncertain dynamics is presented. Longitudinal GTM dynamics are considered. An Hinfinity

  6. Bumblebee Flight in Heavy Turbulence

    NASA Astrophysics Data System (ADS)

    Engels, T.; Kolomenskiy, D.; Schneider, K.; Lehmann, F.-O.; Sesterhenn, J.

    2016-01-01

    High-resolution numerical simulations of a tethered model bumblebee in forward flight are performed superimposing homogeneous isotropic turbulent fluctuations to the uniform inflow. Despite tremendous variation in turbulence intensity, between 17% and 99% with respect to the mean flow, we do not find significant changes in cycle-averaged aerodynamic forces, moments, or flight power when averaged over realizations, compared to laminar inflow conditions. The variance of aerodynamic measures, however, significantly increases with increasing turbulence intensity, which may explain flight instabilities observed in freely flying bees.

  7. SPIRIT 1 Final Flight Report

    DTIC Science & Technology

    1991-05-15

    If _ PL-TR-91-2226 Environmental Research Papers, No.1094 AD-A257 088" S PI R IT I llll l ii l li l IilI FINAL FLIGHT REPORT Donald R. Smith Michael...24213• :_• ./1111111111 II/ ll/ I111ll /i l ! 1111 I~lll’ "This technical report has been reviewed and is approved for publication" ,’TP" D. PRICE...the 500- to 2000-cm-1 (5- to 20-jim) region. This report provides a detailed overview of the SPIRIT 1 flight and mission and the analysis of the flight

  8. Calcium Kinetics During Space Flight

    NASA Technical Reports Server (NTRS)

    Smith, Scott M.; OBrien, K. O.; Abrams, S. A.; Wastney, M. E.

    2005-01-01

    Bone loss during space flight is one of the most critical challenges to astronaut health on space exploration missions. Defining the time course and mechanism of these changes will aid in developing means to counteract bone loss during space flight, and will have relevance for other clinical situations that impair weight-bearing activity. Bone health is a product of the balance between bone formation and bone resorption. Early space research could not clearly identify which of these was the main process altered in bone loss, but identification of the collagen crosslinks in the 1990s made possible a clear understanding that the impact of space flight was greater on bone resorption, with bone formation being unchanged or only slightly decreased. Calcium kinetics data showed that bone resorption was greater during flight than before flight (668 plus or minus 130 vs. 427 plus or minus 153 mg/d, p less than 0.001), and clearly documented that true intestinal calcium absorption was lower during flight than before flight (233 plus or minus 87 vs. 460 plus or minus 47 mg/d, p less than 0.01). Weightlessness had a detrimental effect on the balance in bone turnover: the difference between daily calcium balance during flight (-234 plus or minus 102 mg/d) and calcium balance before flight (63 plus or minus 75 mg/d) approached 300 mg/d (p less than 0.01). These data demonstrate that the bone loss that occurs during space flight is a consequence of increased bone resorption and decreased intestinal calcium absorption. Examining the changes in bone and calcium homeostasis in the initial days and weeks of space flight, as well as at later times on missions longer than 6 months, is critical to understanding the nature of bone adaptation to weightlessness. To increase knowledge of these changes, we studied bone adaptation to space flight on the 16-day Space Shuttle Columbia (STS-107) mission. When the brave and talented crew of Columbia were lost during reentry on the tragic morning

  9. Flight Rules Critical Readiness Review

    NASA Technical Reports Server (NTRS)

    Kim, E.; Knudsen, F.; Rice, S.

    2010-01-01

    The increment 23/24 Critical Readiness Review (CRR) flight rules are presented. The topics include: 1) B13-152 Acoustic Constraints; 2) B13-113 IFM/Corrective Action Prioritization Due to Loss of Exercise Capability; 3) B13-116 Constraints on Treadmill VIS Failure; 4) B13-201 Medical Management of ISS Fire/Smoke Response; 5) ARED and T2 Exercise constraints Flight rules (flight and stage specific); 6) FYI: B14 FR to be updated with requirement to sample crew sleep locations prior to receiving a "recommendation" from SRAG on where to sleep.

  10. Vapor Compression Distillation Flight Experiment

    NASA Technical Reports Server (NTRS)

    Hutchens, Cindy F.

    2002-01-01

    One of the major requirements associated with operating the International Space Station is the transportation -- space shuttle and Russian Progress spacecraft launches - necessary to re-supply station crews with food and water. The Vapor Compression Distillation (VCD) Flight Experiment, managed by NASA's Marshall Space Flight Center in Huntsville, Ala., is a full-scale demonstration of technology being developed to recycle crewmember urine and wastewater aboard the International Space Station and thereby reduce the amount of water that must be re-supplied. Based on results of the VCD Flight Experiment, an operational urine processor will be installed in Node 3 of the space station in 2005.

  11. Cardiovascular function in space flight

    NASA Technical Reports Server (NTRS)

    Nicogossian, A. E.; Charles, J. B.; Bungo, M. W.; Leach-Huntoon, C. S.

    1990-01-01

    Postflight orthostatic intolerance and cardiac hemodynamics associated with manned space flight have been investigated on seven STS missions. Orthostatic heart rates appear to be influenced by the mission duration. The rates increase during the first 7-10 days of flight and recover partially after that. Fluid loading is used as a countermeasure to the postflight orthostatic intolerance. The carotid baroreceptor function shows only slight responsiveness to orthostatic stimulation. Plots of the baroreceptor function are presented. It is concluded that an early adaptation to the space flight conditions involves a fluid shift and that the subsequent alterations in the neutral controlling mechanisms contribute to the orthoststic intolerance.

  12. Immune responses in space flight

    NASA Technical Reports Server (NTRS)

    Sonnenfeld, G.

    1998-01-01

    Space flight has been shown to have profound effects on immunological parameters of humans, monkeys and rodents. These studies have been carried out by a number of different laboratories. Among the parameters affected are leukocyte blastogenesis, natural killer cell activity, leukocyte subset distribution, cytokine production - including interferons and interleukins, and macrophage maturation and activity. These changes start to occur only after a few days space flight, and some changes continue throughout long-term space flight. Antibody responses have received only very limited study, and total antibody levels have been shown to be increased after long-term space flight. Several factors could be involved in inducing these changes. These factors could include microgravity, lack of load-bearing, stress, acceleration forces, and radiation. The mechanism(s) for space flight-induced changes in immune responses remain(s) to be established. Certainly, there can be direct effects of microgravity, or other factors, on cells that play a fundamental role in immune responses. However, it is now clear that there are interactions between the immune system and other physiological systems that could play a major role. For example, changes occurring in calcium use in the musculoskeletal system induced by microgravity or lack of use could have great impact on the immune system. Most of the changes in immune responses have been observed using samples taken immediately after return from space flight. However, there have been two recent studies that have used in-flight testing. Delayed-type hypersensitivity responses to common recall antigens of astronauts and cosmonauts have been shown to be decreased when tested during space flights. Additionally, natural killer cell and blastogenic activities are inhibited in samples taken from rats during space flight. Therefore, it is now clear that events occurring during space flight itself can affect immune responses. The biological

  13. Shortest path and Schramm-Loewner Evolution

    PubMed Central

    Posé, N.; Schrenk, K. J.; Araújo, N. A. M.; Herrmann, H. J.

    2014-01-01

    We numerically show that the statistical properties of the shortest path on critical percolation clusters are consistent with the ones predicted for Schramm-Loewner evolution (SLE) curves for κ = 1.04 ± 0.02. The shortest path results from a global optimization process. To identify it, one needs to explore an entire area. Establishing a relation with SLE permits to generate curves statistically equivalent to the shortest path from a Brownian motion. We numerically analyze the winding angle, the left passage probability, and the driving function of the shortest path and compare them to the distributions predicted for SLE curves with the same fractal dimension. The consistency with SLE opens the possibility of using a solid theoretical framework to describe the shortest path and it raises relevant questions regarding conformal invariance and domain Markov properties, which we also discuss. PMID:24975019

  14. A clinical path for adult diabetes.

    PubMed

    Courtney, L; Gordon, M; Romer, L

    1997-01-01

    The use of clinical paths for patient care management was explored by this development team as a mechanism to provide consistent, high-quality care to hospitalized patients in high-volume, high-risk diagnostic categories. Reviewing the historical aspects and importance of clinical paths helped expand the team's perspective to incorporate pre- and posthospitalization phases of patient care into the clinical path being developed. A multidisciplinary team of physicians, nurses, health educators, and dietitians from both inpatient and outpatient departments of Kaiser-Santa Teresa Medical Center in San Jose, California, devised and implemented an Adult Diabetes Mellitus care path. Staff education preceded the implementation of the care paths. Measurements of quality indicators showed improvements in patient satisfaction, patient education, patient knowledge, and nutrition assessments.

  15. Topological Path Planning in GPS Trajectory Data

    PubMed Central

    Corcoran, Padraig

    2016-01-01

    This paper proposes a novel solution to the problem of computing a set of topologically inequivalent paths between two points in a space given a set of samples drawn from that space. Specifically, these paths are homotopy inequivalent where homotopy is a topological equivalence relation. This is achieved by computing a basis for the group of homology inequivalent loops in the space. An additional distinct element is then computed where this element corresponds to a loop which passes through the points in question. The set of paths is subsequently obtained by taking the orbit of this element acted on by the group of homology inequivalent loops. Using a number of spaces, including a street network where the samples are GPS trajectories, the proposed method is demonstrated to accurately compute a set of homotopy inequivalent paths. The applications of this method include path and coverage planning. PMID:28009817

  16. Iced Aircraft Flight Data for Flight Simulator Validation

    NASA Technical Reports Server (NTRS)

    Ratvasky, Thomas P.; Blankenship, Kurt; Rieke, William; Brinker, David J.

    2003-01-01

    NASA is developing and validating technology to incorporate aircraft icing effects into a flight training device concept demonstrator. Flight simulation models of a DHC-6 Twin Otter were developed from wind tunnel data using a subscale, complete aircraft model with and without simulated ice, and from previously acquired flight data. The validation of the simulation models required additional aircraft response time histories of the airplane configured with simulated ice similar to the subscale model testing. Therefore, a flight test was conducted using the NASA Twin Otter Icing Research Aircraft. Over 500 maneuvers of various types were conducted in this flight test. The validation data consisted of aircraft state parameters, pilot inputs, propulsion, weight, center of gravity, and moments of inertia with the airplane configured with different amounts of simulated ice. Emphasis was made to acquire data at wing stall and tailplane stall since these events are of primary interest to model accurately in the flight training device. Analyses of several datasets are described regarding wing and tailplane stall. Key findings from these analyses are that the simulated wing ice shapes significantly reduced the C , max, while the simulated tail ice caused elevator control force anomalies and tailplane stall when flaps were deflected 30 deg or greater. This effectively reduced the safe operating margins between iced wing and iced tail stall as flap deflection and thrust were increased. This flight test demonstrated that the critical aspects to be modeled in the icing effects flight training device include: iced wing and tail stall speeds, flap and thrust effects, control forces, and control effectiveness.

  17. Flight Testing a Digital Flight Control System. Issues and Results

    DTIC Science & Technology

    1984-07-01

    Program is primarily oriented to the development, integration, and I - evaluation of new flight control technologies . The testbed used in this program is...will be tested for safe operations to give confidence in case of non-rUettable automatic IBU engagement. ISSUE: CONTROL LAW AND REDUNDANCY MAGEMENT CO...were available. Being an advanced development program evaluating new aspects of integrated flight control technology , the latter approach was chosen

  18. Infrared Sensing Aeroheating Flight Experiment: STS-96 Flight Results

    NASA Technical Reports Server (NTRS)

    Blanchard, Robert C.; Wilmoth, Richard G.; Glass, Christopher E.; Merski, N. Ronald, Jr.; Berry, Scott A.; Bozung, Timothy J.; Tietjen, Alan; Wendt, Jodean; Dawson, Don

    2001-01-01

    Major elements of an experiment called the Infrared Sensing Aeroheating Flight Experiment are discussed. The primary experiment goal is to provide reentry global temperature images from infrared measurements to define the characteristics of hypersonic boundary-layer transition during flight. Specifically, the experiment is to identify, monitor, and quantity hypersonic boundary layer windward surface transition of the X-33 vehicle during flight. In addition, the flight data will serve as a calibration and validation of current boundary layer transition prediction techniques, provide benchmark laminar, transitional, and fully turbulent global aeroheating data in order to validate existing wind tunnel and computational results, and to advance aeroheating technology. Shuttle Orbiter data from STS-96 used to validate the data acquisition and data reduction to global temperatures, in order to mitigate the experiment risks prior to the maiden flight of the X-33, is discussed. STS-96 reentry midwave (3-5 micron) infrared data were collected at the Ballistic Missile Defense Organization/Innovative Sciences and Technology Experimentation Facility site at NASA-Kennedy Space Center and subsequently mapped into global temperature contours using ground calibrations only. A series of image mapping techniques have been developed in order to compare each frame of infrared data with thermocouple data collected during the flight. Comparisons of the ground calibrated global temperature images with the corresponding thermocouple data are discussed. The differences are shown to be generally less than about 5%, which is comparable to the expected accuracy of both types of aeroheating measurements.

  19. Identification of a typical flight patterns

    NASA Technical Reports Server (NTRS)

    Statler, Irving C. (Inventor); Ferryman, Thomas A (Inventor); Amidan, Brett G. (Inventor); Whitney, Paul D. (Inventor); White, M. (Inventor); Willse, Alan R. (Inventor); Cooley, Scott K. (Inventor); Jay, Joseph Griffith (Inventor); Lawrence, Robert E. (Inventor); Mosbrucker, Chris (Inventor)

    2005-01-01

    Method and system for analyzing aircraft data, including multiple selected flight parameters for a selected phase of a selected flight, and for determining when the selected phase of the selected flight is atypical, when compared with corresponding data for the same phase for other similar flights. A flight signature is computed using continuous- valued and discrete-valued flight parameters for the selected flight parameters and is optionally compared with a statistical distribution of other observed flight signatures, yielding a typicality scores for the same phase for other similar flights. A cluster analysis is optionally applied to the flight signatures to define an optimal collection of clusters. A level of atypicality for a selected flight is estimated, based upon an index associated with the cluster analysis.

  20. Minimum-Energy Flight Paths for UAVs Using Mesoscale Wind Forecasts and Approximate Dynamic Programming

    DTIC Science & Technology

    2007-12-01

    24) ( , ) ( ) ij arc i j D x dx DX=∫ . All of the processes that lead to loss of energy, including drag, will eventually be translated to heating of...the wind field as a function of altitude, up to 10 km, according to a 160 km x 160 km COAMPS forecast over Yucca, Nevada test site, for (a) wind...for two cases: (a) | | 90ijβ γ− ≤ and (b) | | 90ijβ γ− ≥ ..................................................27  x Figure 15.  A circular turn from