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Sample records for aircraft handling qualities

  1. Analysis of aircraft longitudinal handling qualities

    NASA Technical Reports Server (NTRS)

    Hess, R. A.

    1981-01-01

    The optimal control model (OCM) of the human pilot is applied to the study of aircraft handling qualities. Attention is focused primarily on longitudinal tasks. The modeling technique differs from previous applications of the OCM in that considerable effort is expended in simplifying the pilot/vehicle analysis. After briefly reviewing the OCM, a technique for modeling the pilot controlling higher order systems is introduced. Following this, a simple criterion for determining the susceptibility of an aircraft to pilot induced oscillations (PIO) is formulated. Finally, a model-based metric for pilot rating prediction is discussed. The resulting modeling procedure provides a relatively simple, yet unified approach to the study of a variety of handling qualities problems.

  2. An Investigation of Large Aircraft Handling Qualities

    NASA Astrophysics Data System (ADS)

    Joyce, Richard D.

    An analytical technique for investigating transport aircraft handling qualities is exercised in a study using models of two such vehicles, a Boeing 747 and Lockheed C-5A. Two flight conditions are employed for climb and directional tasks, and a third included for a flare task. The analysis technique is based upon a "structural model" of the human pilot developed by Hess. The associated analysis procedure has been discussed previously in the literature, but centered almost exclusively on the characteristics of high-performance fighter aircraft. The handling qualities rating level (HQRL) and pilot induced oscillation tendencies rating level (PIORL) are predicted for nominal configurations of the aircraft and for "damaged" configurations where actuator rate limits are introduced as nonlinearites. It is demonstrated that the analysis can accommodate nonlinear pilot/vehicle behavior and do so in the context of specific flight tasks, yielding estimates of handling qualities, pilot-induced oscillation tendencies and upper limits of task performance. A brief human-in-the-loop tracking study was performed to provide a limited validation of the pilot model employed.

  3. Theoretical and experimental methods to select aircraft handling qualities

    NASA Astrophysics Data System (ADS)

    Zaichik, L. E.; Yashin, Y. P.; Perebatov, V. S.; Desyatnik, P. A.

    2013-12-01

    A theoretical-experimental method is developed to analyze and adequately select aircraft handling qualities (HQ). A review is presented of the criteria developed by the authors to estimate the role of motion cues in controlling of an aircraft, and criteria to estimate the on-ground simulation fidelity. The method is presented to translate on-ground simulation results into real flight conditions.

  4. Handling Qualities of Large Flexible Aircraft. Ph.D. Thesis

    NASA Technical Reports Server (NTRS)

    Poopaka, S.

    1980-01-01

    The effects on handling qualities of elastic modes interaction with the rigid body dynamics of a large flexible aircraft are studied by a mathematical computer simulation. An analytical method to predict the pilot ratings when there is a severe modes interactions is developed. This is done by extending the optimal control model of the human pilot response to include the mode decomposition mechanism into the model. The handling qualities are determined for a longitudinal tracking task using a large flexible aircraft with parametric variations in the undamped natural frequencies of the two lowest frequency, symmetric elastic modes made to induce varying amounts of mode interaction.

  5. Criteria for Handling Qualities of Military Aircraft.

    DTIC Science & Technology

    1982-06-01

    loop precognitive manner. The pilot is able to apply discrete, step-like inputs which more or less exactly produce the desired aircraft response. Some...While closed loop operation depends upon the frequency domain response characteristics, successful precognitive control requires the time domain...represents the other extreme of the pilot task from the precognitive time response situation. Mich work was done in attempting to predict pilot opinion from

  6. Modeling procedures for handling qualities evaluation of flexible aircraft

    NASA Technical Reports Server (NTRS)

    Govindaraj, K. S.; Eulrich, B. J.; Chalk, C. R.

    1981-01-01

    This paper presents simplified modeling procedures to evaluate the impact of flexible modes and the unsteady aerodynamic effects on the handling qualities of Supersonic Cruise Aircraft (SCR). The modeling procedures involve obtaining reduced order transfer function models of SCR vehicles, including the important flexible mode responses and unsteady aerodynamic effects, and conversion of the transfer function models to time domain equations for use in simulations. The use of the modeling procedures is illustrated by a simple example.

  7. The effects of aircraft design and atmospheric turbulence on handling and ride qualities

    NASA Technical Reports Server (NTRS)

    Jones, C. R.; Jacobson, I. D.

    1976-01-01

    The effects of aircraft dynamic characteristics on passenger ride quality were investigated to determine ride-quality isocontours similar to aircraft handling-qualities contours. Measurements were made on a motion-base simulator while varying the aircraft short-period and Dutch Roll frequencies and dampings. Both pilot ratings and subjective ride-quality ratings were obtained during simulator flight. Ride and handling qualities were found to be complimentary for the Dutch Roll mode, but not for the short-period mode. Regions of optimal ride and handling qualities were defined for the short-period mode, and the effects of changes in turbulence level studied using mathematical models.

  8. Handling Quality Requirements for Advanced Aircraft Design: Longitudinal Mode

    DTIC Science & Technology

    1979-08-01

    regarded by implication or otherwise as in any manner licensing the holder or any other person or corporation, or conveying any rights or permission...analog hardware specifications and seleccion on the DFCS performance. * Consideration of the potential degradation of DFCS performance and handling...systems research or even for the engineering design of an aircraft or FCS, matters of style and personal taste can dictate how one chooses to

  9. Unified Theory for Aircraft Handling Qualities and Adverse Aircraft-Pilot Coupling

    NASA Technical Reports Server (NTRS)

    Hess, R. A.

    1997-01-01

    A unified theory for aircraft handling qualities and adverse aircraft-pilot coupling or pilot-induced oscillations is introduced. The theory is based on a structural model of the human pilot. A methodology is presented for the prediction of (1) handling qualities levels; (2) pilot-induced oscillation rating levels; and (3) a frequency range in which pilot-induced oscillations are likely to occur. Although the dynamics of the force-feel system of the cockpit inceptor is included, the methodology will not account for effects attributable to control sensitivity and is limited to single-axis tasks and, at present, to linear vehicle models. The theory is derived from the feedback topology of the structural model and an examination of flight test results for 32 aircraft configurations simulated by the U.S. Air Force/CALSPAN NT-33A and Total In-Flight Simulator variable stability aircraft. An extension to nonlinear vehicle dynamics such as that encountered with actuator saturation is discussed.

  10. Handling Qualities Prediction of an F-16XL-Based Reduced Sonic Boom Aircraft

    NASA Technical Reports Server (NTRS)

    Cogan, Bruce; Yoo, Seung

    2010-01-01

    A major goal of the Supersonics Project under NASA s Fundamental Aeronautics program is sonic boom reduction of supersonic aircraft. An important part of this effort is development and validation of sonic boom prediction tools used in aircraft design. NASA Dryden s F- 16XL was selected as a potential testbed aircraft to provide flight validation. Part of this task was predicting the handling qualities of the modified aircraft. Due to the high cost of modifying the existing F-16XL control laws, it was desirable to find modifications that reduced the aircraft sonic boom but did not degrade baseline aircraft handling qualities allowing for the potential of flight test without changing the current control laws. This was not a requirement for the initial modification design work, but an important consideration for proceeding to the flight test option. The primary objective of this work was to determine an aerodynamic and mass properties envelope of the F-16XL aircraft. The designers could use this envelope to determine the effect of proposed modifications on aircraft handling qualities.

  11. Analysis of Aircraft Control Performance using a Fuzzy Rule Base Representation of the Cooper-Harper Aircraft Handling Quality Rating

    NASA Technical Reports Server (NTRS)

    Tseng, Chris; Gupta, Pramod; Schumann, Johann

    2006-01-01

    The Cooper-Harper rating of Aircraft Handling Qualities has been adopted as a standard for measuring the performance of aircraft since it was introduced in 1966. Aircraft performance, ability to control the aircraft, and the degree of pilot compensation needed are three major key factors used in deciding the aircraft handling qualities in the Cooper- Harper rating. We formulate the Cooper-Harper rating scheme as a fuzzy rule-based system and use it to analyze the effectiveness of the aircraft controller. The automatic estimate of the system-level handling quality provides valuable up-to-date information for diagnostics and vehicle health management. Analyzing the performance of a controller requires a set of concise design requirements and performance criteria. Ir, the case of control systems fm a piloted aircraft, generally applicable quantitative design criteria are difficult to obtain. The reason for this is that the ultimate evaluation of a human-operated control system is necessarily subjective and, with aircraft, the pilot evaluates the aircraft in different ways depending on the type of the aircraft and the phase of flight. In most aerospace applications (e.g., for flight control systems), performance assessment is carried out in terms of handling qualities. Handling qualities may be defined as those dynamic and static properties of a vehicle that permit the pilot to fully exploit its performance in a variety of missions and roles. Traditionally, handling quality is measured using the Cooper-Harper rating and done subjectively by the human pilot. In this work, we have formulated the rules of the Cooper-Harper rating scheme as fuzzy rules with performance, control, and compensation as the antecedents, and pilot rating as the consequent. Appropriate direct measurements on the controller are related to the fuzzy Cooper-Harper rating system: a stability measurement like the rate of change of the cost function can be used as an indicator if the aircraft is under

  12. A design procedure for the handling qualities optimization of the X-29A aircraft

    NASA Technical Reports Server (NTRS)

    Bosworth, John T.; Cox, Timothy H.

    1989-01-01

    A design technique for handling qualities improvement was developed for the X-29A aircraft. As with any new aircraft, the X-29A control law designers were presented with a relatively high degree of uncertainty in their mathematical models. The presence of uncertainties, and the high level of static instability of the X-29A caused the control law designers to stress stability and robustness over handling qualities. During flight test, the mathematical models of the vehicle were validated or corrected to match the vehicle dynamic behavior. The updated models were then used to fine tune the control system to provide fighter-like handling characteristics. A design methodology was developed which works within the existing control system architecture to provide improved handling qualities and acceptable stability with a minimum of cost in both implementation as well as software verification and validation.

  13. Evaluating the Handling Qualities of Flight Control Systems Including Nonlinear Aircraft and System Dynamics

    NASA Astrophysics Data System (ADS)

    Lin, Raymond Chao

    The handling qualities evaluation of nonlinear aircraft systems is an area of concern in loss-of-control (LOC) prevention. The Get Transfer Function (GetTF) method was demonstrated for evaluating the handling qualities of flight control systems and aircraft containing nonlinearities. NASA's Generic Transport Model (GTM), a nonlinear model of a civilian jet transport aircraft, was evaluated. Using classical techniques, the stability, control, and augmentation (SCAS) systems were designed to control pitch rate, roll rate, and airspeed. Hess's structural pilot model was used to model pilot dynamics in pitch and roll-attitude tracking. The simulated task was simultaneous tracking of, both, pitch and roll attitudes. Eight cases were evaluated: 1) gain increase of pitch-attitude command signal, 2) gain increase of roll-attitude command signal, 3) gain reduction of elevator command signal, 4) backlash in elevator actuator, 5) combination 3 and 4 in elevator actuator, 6) gain reduction of aileron command signal, 7) backlash in aileron actuator, and 8) combination of 6 and 7 in aileron actuator. The GetTF method was used to estimate the transfer function approximating a linear relationship between the proprioceptive signal of the pilot model and the command input. The transfer function was then used to predict the handling qualities ratings (HQR) and pilot-induced oscillation ratings (PIOR). The HQR is based on the Cooper-Harper rating scale. In pitch-attitude tracking, the nominal aircraft is predicted to have Level 2* HQRpitch and 2 < PIORpitch < 4. The GetTF method generally predicted degraded handling qualities for cases with impaired actuators. The results demonstrate GetTF's utility in evaluating the handling qualities during the design phase of flight control and aircraft systems. A limited human-in-the-loop pitch tracking exercise was also conducted to validate the structural pilot model.

  14. Analysis of flexible aircraft longitudinal dynamics and handling qualities. Volume 1: Analysis methods

    NASA Technical Reports Server (NTRS)

    Waszak, M. R.; Schmidt, D. S.

    1985-01-01

    As aircraft become larger and lighter due to design requirements for increased payload and improved fuel efficiency, they will also become more flexible. For highly flexible vehicles, the handling qualities may not be accurately predicted by conventional methods. This study applies two analysis methods to a family of flexible aircraft in order to investigate how and when structural (especially dynamic aeroelastic) effects affect the dynamic characteristics of aircraft. The first type of analysis is an open loop model analysis technique. This method considers the effects of modal residue magnitudes on determining vehicle handling qualities. The second method is a pilot in the loop analysis procedure that considers several closed loop system characteristics. Volume 1 consists of the development and application of the two analysis methods described above.

  15. A design procedure for the handling qualities optimization of the X-29A aircraft

    NASA Technical Reports Server (NTRS)

    Bosworth, John T.; Cox, Timothy H.

    1989-01-01

    The techniques used to improve the pitch-axis handling qualities of the X-29A wing-canard-planform fighter aircraft are reviewed. The aircraft and its FCS are briefly described, and the design method, which works within the existing FCS architecture, is characterized in detail. Consideration is given to the selection of design goals and design variables, the definition and calculation of the cost function, the validation of the mathematical model on the basis of flight-test data, and the validation of the improved design by means of nonlinear simulations. Flight tests of the improved design are shown to verify the simulation results.

  16. Analysis of flexible aircraft longitudinal dynamics and handling qualities. Volume 2: Data

    NASA Technical Reports Server (NTRS)

    Waszak, M. R.; Schmidt, D. K.

    1985-01-01

    Two analysis methods are applied to a family of flexible aircraft in order to investigate how and when structural (especially dynamic aeroelastic) effects affect the dynamic characteristics of aircraft. The first type of analysis is an open loop modal analysis technique. This method considers the effect of modal residue magnitudes on determining vehicle handling qualities. The second method is a pilot in the loop analysis procedure that considers several closed loop system characteristics. Both analyses indicated that dynamic aeroelastic effects caused a degradation in vehicle tracking performance, based on the evaluation of some simulation results. Volume 2 consists of the presentation of the state variable models of the flexible aircraft configurations used in the analysis applications mode shape plots for the structural modes, numerical results from the modal analysis frequency response plots from the pilot in the loop analysis and a listing of the modal analysis computer program.

  17. Piloted Simulation Assessment of the Impact of Flexible Structures on Handling Qualities of Generic Supersonic Aircraft

    NASA Technical Reports Server (NTRS)

    Stringer, Mary T.; Cowen, Brandon; Hoffler, Keith D.; Couch, Jesse C.; Ogburn, Marilyn E.; Diebler, Corey G.

    2013-01-01

    The NASA Langley Research Center Cockpit Motion Facility (CMF) was used to conduct a piloted simulation assessment of the impact of flexible structures on flying qualities. The CMF was used because of its relatively high bandwidth, six degree-of-freedom motion capability. Previous studies assessed and attempted to mitigate the effects of multiple dynamic aeroservoelastic modes (DASE). Those results indicated problems existed, but the specific cause and effect was difficult to ascertain. The goal of this study was to identify specific DASE frequencies, damping ratios, and gains that cause degradation in handling qualities. A generic aircraft simulation was developed and designed to have Cooper-Harper Level 1 handling qualities when flown without DASE models. A test matrix of thirty-six DASE modes was implemented. The modes had frequencies ranging from 1 to 3.5 Hz and were applied to each axis independently. Each mode consisted of a single axis, frequency, damping, and gain, and was evaluated individually by six subject pilots with test pilot backgrounds. Analysis completed to date suggests that a number of the DASE models evaluated degrade the handling qualities of this class of aircraft to an uncontrollable condition.

  18. Development of longitudinal handling qualities criteria for large advanced supersonic aircraft

    NASA Technical Reports Server (NTRS)

    Sudderth, R. W.; Mcneill, W. E.

    1976-01-01

    A piloted simulation study was conducted with the aim of advancing the development of longitudinal handling qualities criteria for large supersonic cruise aircraft. The areas of study investigated included high-speed cruise maneuvering, and stall-recovery control power. Comparisons were made with existing criteria and, for the cruise condition, a time response criterion was developed which correlated well with pilot ratings and comments. For low-speed stall recovery a new criterion was developed in terms of nose-down angular acceleration capability.

  19. Flight Validation of a Handling Qualities Metric for a Damaged Aircraft

    NASA Technical Reports Server (NTRS)

    Cogan, Bruce R.

    2009-01-01

    Objectives: a) Develop an asymmetric handling qualities metric to predict cross coupling effects of a damaged aircraft: 1) Initial use of U.S Army Aeronautical Design Specification ADS-33; 2) Modification as required based on flight test results. b) Simulation and Flight Validation of proposed metric: 1) F-16 VISTA (March 2010); 2) F-18 Full Scale Test bed (Potential Early Experiment); and 3) Flight Simulators (GTM, ACFS, F-18 HILS). c) Provide flight validated metric and tool box to control law designers.

  20. Modal control theory and application to aircraft lateral handling qualities design

    NASA Technical Reports Server (NTRS)

    Srinathkumar, S.

    1978-01-01

    A multivariable synthesis procedure based on eigenvalue/eigenvector assignment is reviewed and is employed to develop a systematic design procedure to meet the lateral handling qualities design objectives of a fighter aircraft over a wide range of flight conditions. The closed loop modal characterization developed provides significant insight into the design process and plays a pivotal role in the synthesis of robust feedback systems. The simplicity of the synthesis algorithm yields an efficient computer aided interactive design tool for flight control system synthesis.

  1. Effect of winglets on performance and handling qualities of general aviation aircraft

    NASA Technical Reports Server (NTRS)

    Van Dam, C. P.; Holmes, B. J.; Pitts, C.

    1980-01-01

    Recent flight and wind tunnel evaluations of winglets mounted on general aviation airplanes have shown improvements in cruise fuel efficiency, and climbing and turning performance. Some of these analyses have also uncovered various effects of winglets on airplane handling qualities. Retrofitting an airplane with winglets can result in reduced cross wind take-off and landing capabilities. Also, winglets can have a detrimental effect on the lateral directional response characteristics of aircraft which have a moderate to high level of adverse yaw due to aileron. Introduction of an aileron-rudder-interconnect, and reduction of the effective dihedral by canting-in of the winglets, or addition of a lower winglet can eliminate these flying quality problems.

  2. Estimation of Handling Qualities Parameters of the Tu-144 Supersonic Transport Aircraft from Flight Test Data

    NASA Technical Reports Server (NTRS)

    Curry, Timothy J.; Batterson, James G. (Technical Monitor)

    2000-01-01

    Low order equivalent system (LOES) models for the Tu-144 supersonic transport aircraft were identified from flight test data. The mathematical models were given in terms of transfer functions with a time delay by the military standard MIL-STD-1797A, "Flying Qualities of Piloted Aircraft," and the handling qualities were predicted from the estimated transfer function coefficients. The coefficients and the time delay in the transfer functions were estimated using a nonlinear equation error formulation in the frequency domain. Flight test data from pitch, roll, and yaw frequency sweeps at various flight conditions were used for parameter estimation. Flight test results are presented in terms of the estimated parameter values, their standard errors, and output fits in the time domain. Data from doublet maneuvers at the same flight conditions were used to assess the predictive capabilities of the identified models. The identified transfer function models fit the measured data well and demonstrated good prediction capabilities. The Tu-144 was predicted to be between level 2 and 3 for all longitudinal maneuvers and level I for all lateral maneuvers. High estimates of the equivalent time delay in the transfer function model caused the poor longitudinal rating.

  3. A modal analysis of flexible aircraft dynamics with handling qualities implications

    NASA Technical Reports Server (NTRS)

    Schmidt, D. K.

    1983-01-01

    A multivariable modal analysis technique is presented for evaluating flexible aircraft dynamics, focusing on meaningful vehicle responses to pilot inputs and atmospheric turbulence. Although modal analysis is the tool, vehicle time response is emphasized, and the analysis is performed on the linear, time-domain vehicle model. In evaluating previously obtained experimental pitch tracking data for a family of vehicle dynamic models, it is shown that flexible aeroelastic effects can significantly affect pitch attitude handling qualities. Consideration of the eigenvalues alone, of both rigid-body and aeroelastic modes, does not explain the simulation results. Modal analysis revealed, however, that although the lowest aeroelastic mode frequency was still three times greater than the short-period frequency, the rigid-body attitude response was dominated by this aeroelastic mode. This dominance was defined in terms of the relative magnitudes of the modal residues in selected vehicle responses.

  4. Development of longitudinal handling qualities criteria for large advanced supersonic aircraft

    NASA Technical Reports Server (NTRS)

    Sudderth, R. W.; Bohn, J. G.; Caniff, M. A.; Bennett, G. R.

    1975-01-01

    Longitudinal handling qualities criteria in terms of airplane response characteristics were developed. The criteria cover high speed cruise maneuvering, landing approach, and stall recovery. Data substantiating the study results are reported.

  5. Aircraft model prototypes which have specified handling-quality time histories

    NASA Technical Reports Server (NTRS)

    Johnson, S. H.

    1976-01-01

    Several techniques for obtaining linear constant-coefficient airplane models from specified handling-quality time histories are discussed. One technique, the pseudodata method, solves the basic problem, yields specified eigenvalues, and accommodates state-variable transfer-function zero suppression. The method is fully illustrated for a fourth-order stability-axis small-motion model with three lateral handling-quality time histories specified. The FORTRAN program which obtains and verifies the model is included and fully documented.

  6. Aircraft model prototypes which have specified handling-quality time histories

    NASA Technical Reports Server (NTRS)

    Johnson, S. H.

    1978-01-01

    Several techniques for obtaining linear constant-coefficient airplane models from specified handling-quality time histories are discussed. The pseudodata method solves the basic problem, yields specified eigenvalues, and accommodates state-variable transfer-function zero suppression. The algebraic equations to be solved are bilinear, at worst. The disadvantages are reduced generality and no assurance that the resulting model will be airplane like in detail. The method is fully illustrated for a fourth-order stability-axis small motion model with three lateral handling quality time histories specified. The FORTRAN program which obtains and verifies the model is included and fully documented.

  7. Interpreting the handling qualities of aircraft with stability and control augmentation

    NASA Technical Reports Server (NTRS)

    Hodgkinson, J.; Potsdam, E. H.; Smith, R. E.

    1990-01-01

    The general process of designing an aircraft for good flying qualities is first discussed. Lessons learned are pointed out, with piloted evaluation emerging as a crucial element. Two sources of rating variability in performing these evaluations are then discussed. First, the finite endpoints of the Cooper-Harper scale do not bias parametric statistical analyses unduly. Second, the wording of the scale does introduce some scatter. Phase lags generated by augmentation systems, as represented by equivalent time delays, often cause poor flying qualities. An analysis is introduced which allows a designer to relate any level of time delay to a probability of loss of aircraft control. This view of time delays should, it is hoped, allow better visibility of the time delays in the design process.

  8. Longitudinal Handling Qualities of the Tu-144LL Airplane and Comparisons With Other Large, Supersonic Aircraft

    NASA Technical Reports Server (NTRS)

    Cox, Timothy H.; Marshall, Alisa

    2000-01-01

    Four flights have been conducted using the Tu-144LL supersonic transport aircraft with the dedicated objective of collecting quantitative data and qualitative pilot comments. These data are compared with the following longitudinal flying qualities criteria: Neal-Smith, short-period damping, time delay, control anticipation parameter, phase delay (omega(sp)*T(theta(2))), pitch bandwidth as a function of time delay, and flight path as a function of pitch bandwidth. Determining the applicability of these criteria and gaining insight into the flying qualities of a large, supersonic aircraft are attempted. Where appropriate, YF-12, XB-70, and SR-71 pilot ratings are compared with the Tu-144LL results to aid in the interpretation of the Tu-144LL data and to gain insight into the application of criteria. The data show that approach and landing requirements appear to be applicable to the precision flightpath control required for up-and-away flight of large, supersonic aircraft. The Neal-Smith, control anticipation parameter, and pitch-bandwidth criteria tend to correlate with the pilot comments better than the phase delay criterion, omega(sp)*T(theta(2)). The data indicate that the detrimental flying qualities implication of decoupled pitch-attitude and flightpath responses occurring for high-speed flight may be mitigated by requiring the pilot to close the loop on flightpath or vertical speed.

  9. Effects of higher order control systems on aircraft approach and landing longitudinal handling qualities

    NASA Technical Reports Server (NTRS)

    Pasha, M. A.; Dazzo, J. J.; Silverthorn, J. T.

    1982-01-01

    An investigation of approach and landing longitudinal flying qualities, based on data generated using a variable stability NT-33 aircraft combined with significant control system dynamics is described. An optimum pilot lead time for pitch tracking, flight path angle tracking, and combined pitch and flight path angle tracking tasks is determined from a closed loop simulation using integral squared error (ISE) as a performance measure. Pilot gain and lead time were varied in the closed loop simulation of the pilot and aircraft to obtain the best performance for different control system configurations. The results lead to the selection of an optimum lead time using ISE as a performance criterion. Using this value of optimum lead time, a correlation is then found between pilot rating and performance with changes in the control system and in the aircraft dynamics. It is also shown that pilot rating is closely related to pilot workload which, in turn, is related to the amount of lead which the pilot must generate to obtain satisfactory response. The results also indicate that the pilot may use pitch angle tracking for the approach task and then add flight path angle tracking for the flare and touchdown.

  10. The handling qualities and flight characteristics of the Grumman design 698 simulated twin-engine tilt Nacelle V/STOL aircraft

    NASA Technical Reports Server (NTRS)

    Eskey, M. A.; Wilson, S. B., III

    1986-01-01

    This paper describes three government-conducted, piloted flight simulations of the Grumman Design 698 vertical and short takeoff and landing (V/STOL) aircraft. Emphasis is placed on the aircraft's handling qualities as rated by various NASA, Navy, and Grumman Aerospace Corporating pilots with flight experience ranging from conventional takeoff and landing (CTOL) to V/STOL aircraft. Each successive simulation incorporated modifications to the aircraft in order to resolve the flight problems which were of most concern to the pilots in the previous simulation. The objective of the first simulation was to assess the basic handling qualities of the aircraft with the noncross-shafted propulsion system. The objective of the second simulation was to examine the effects of incorporating the cross-shafted propulsion system. The objective of the third simulation was to examine inoperative single-engine characteristics with and without cross-shafted engines.

  11. Aircraft Handling Qualities Data

    DTIC Science & Technology

    1972-12-01

    34 sent an early estimate in the design process and perhaps the "nominal config- uration" is one which never left the drawing board. The data have been...09 * P 0,0 04@0 in WP5 5 4.55 *55 a0p @4 4.em #50 a,45 05555 eO-aO* ൈ 04 40 C’ L tip- left -ൌ It U4 - - -amw --- - - 2 - -- 4 -4 A-a A22 * ~127... seEen -ts and a movable stabilizer. The lateral con- trol empl(ys five srciler ;anels, an inboard aileron between the inboard and outboard flars, and an

  12. Helicopter Handling Qualities

    NASA Technical Reports Server (NTRS)

    1982-01-01

    Helicopters are used by the military and civilian communities for a variety of tasks and must be capable of operating in poor weather conditions and at night. Accompanying extended helicopter operations is a significant increase in pilot workload and a need for better handling qualities. An overview of the status and problems in the development and specification of helicopter handling-qualities criteria is presented. Topics for future research efforts by government and industry are highlighted.

  13. Factors influencing aircraft ground handling performance

    NASA Technical Reports Server (NTRS)

    Yager, T. J.

    1983-01-01

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

  14. Space shuttle handling qualities

    NASA Technical Reports Server (NTRS)

    Gilbert, D. W.

    1985-01-01

    The initial Orbiter handling qualities requirements, their effect on the vehicle design, and how it all turned out through the first six orbital missions are reviewed. Specific areas consisting of hand controller considerations and the wheelie problem are discussed. The requirements for the pitch axis subsonic flight control system are reviewed. Results of recent simulator evaluations to compare the existing system at landing with several other configurations are presented.

  15. Handling Qualities Implications for Crewed Spacecraft Operations

    NASA Technical Reports Server (NTRS)

    Bailey, Randall E.; Jackson, E. Bruce; Arthur, J. J.

    2012-01-01

    Abstract Handling qualities embody those qualities or characteristics of an aircraft that govern the ease and precision with which a pilot is able to perform the tasks required in support of an aircraft role. These same qualities are as critical, if not more so, in the operation of spacecraft. A research, development, test, and evaluation process was put into effect to identify, understand, and interpret the engineering and human factors principles which govern the pilot-vehicle dynamic system as they pertain to space exploration missions and tasks. Toward this objective, piloted simulations were conducted at the NASA Langley Research Center and Ames Research Center for earth-orbit proximity operations and docking and lunar landing. These works provide broad guidelines for the design of spacecraft to exhibit excellent handling characteristics. In particular, this work demonstrates how handling qualities include much more than just stability and control characteristics of a spacecraft or aircraft. Handling qualities are affected by all aspects of the pilot-vehicle dynamic system, including the motion, visual and aural cues of the vehicle response as the pilot performs the required operation or task. A holistic approach to spacecraft design, including the use of manual control, automatic control, and pilot intervention/supervision is described. The handling qualities implications of design decisions are demonstrated using these pilot-in-the-loop evaluations of docking operations and lunar landings.

  16. Handling qualities effects of display latency

    NASA Technical Reports Server (NTRS)

    King, David W.

    1993-01-01

    Display latency is the time delay between aircraft response and the corresponding response of the cockpit displays. Currently, there is no explicit specification for allowable display lags to ensure acceptable aircraft handling qualities in instrument flight conditions. This paper examines the handling qualities effects of display latency between 70 and 400 milliseconds for precision instrument flight tasks of the V-22 Tiltrotor aircraft. Display delay effects on the pilot control loop are analytically predicted through a second order pilot crossover model of the V-22 lateral axis, and handling qualities trends are evaluated through a series of fixed-base piloted simulation tests. The results show that the effects of display latency for flight path tracking tasks are driven by the stability characteristics of the attitude control loop. The data indicate that the loss of control damping due to latency can be simply predicted from knowledge of the aircraft's stability margins, control system lags, and required control bandwidths. Based on the relationship between attitude control damping and handling qualities ratings, latency design guidelines are presented. In addition, this paper presents a design philosophy, supported by simulation data, for using flight director display augmentation to suppress the effects of display latency for delays up to 300 milliseconds.

  17. Handling Qualities of Unstable Highly Augmented Aircraft (Les Caracteristiques de Manoeuvrabilite des Aeronefs Instables a Stabilite Augmentee)

    DTIC Science & Technology

    1991-05-01

    emonstrawr T. ornado 2.h F- 16 (Y’F- 16) 1 1 -7 F-18 (NF- 17) 12 8. Space Shuttle 131 2.) General Aspects of the X-31I Flight Control Sy~steni 14 2.] 10...with extended flight envelopes lead to use of new technologies like active control and control configured unstable vehicles The review of the handling...are presented Other areas of interest are also considered basic aerodynamic design, specific issues relating to the feel system and control

  18. Handling Qualities Optimization for Rotorcraft Conceptual Design

    NASA Technical Reports Server (NTRS)

    Lawrence, Ben; Theodore, Colin R.; Berger, Tom

    2016-01-01

    Over the past decade, NASA, under a succession of rotary-wing programs has been moving towards coupling multiple discipline analyses in a rigorous consistent manner to evaluate rotorcraft conceptual designs. Handling qualities is one of the component analyses to be included in a future NASA Multidisciplinary Analysis and Optimization framework for conceptual design of VTOL aircraft. Similarly, the future vision for the capability of the Concept Design and Assessment Technology Area (CD&A-TA) of the U.S Army Aviation Development Directorate also includes a handling qualities component. SIMPLI-FLYD is a tool jointly developed by NASA and the U.S. Army to perform modeling and analysis for the assessment of flight dynamics and control aspects of the handling qualities of rotorcraft conceptual designs. An exploration of handling qualities analysis has been carried out using SIMPLI-FLYD in illustrative scenarios of a tiltrotor in forward flight and single-main rotor helicopter at hover. Using SIMPLI-FLYD and the conceptual design tool NDARC integrated into a single process, the effects of variations of design parameters such as tail or rotor size were evaluated in the form of margins to fixed- and rotary-wing handling qualities metrics as well as the vehicle empty weight. The handling qualities design margins are shown to vary across the flight envelope due to both changing flight dynamic and control characteristics and changing handling qualities specification requirements. The current SIMPLI-FLYD capability and future developments are discussed in the context of an overall rotorcraft conceptual design process.

  19. Cooper-Harper Experience Report for Spacecraft Handling Qualities Applications

    NASA Technical Reports Server (NTRS)

    Bailey, Randall E.; Jackson, E. Bruce; Bilimoria, Karl D.; Mueller, Eric R.; Frost, Chad R.; Alderete, Thomas S.

    2009-01-01

    A synopsis of experience from the fixed-wing and rotary-wing aircraft communities in handling qualities development and the use of the Cooper-Harper pilot rating scale is presented as background for spacecraft handling qualities research, development, test, and evaluation (RDT&E). In addition, handling qualities experiences and lessons-learned from previous United States (US) spacecraft developments are reviewed. This report is intended to provide a central location for references, best practices, and lessons-learned to guide current and future spacecraft handling qualities RDT&E.

  20. The effects of aircraft design on STOL ride quality

    NASA Technical Reports Server (NTRS)

    Jones, C. R.; Jacobson, I. D.

    1975-01-01

    Effects of aircraft dynamic characteristics on passenger ride quality are investigated to determine ride-quality isocontours similar to aircraft handling-qualities contours. Measurements are made on a moving-base simulator while varying the aircraft short-period and Dutch Roll frequencies and dampings. Both pilot ratings and subjective ride-quality ratings are obtained during flight. Ride and handling qualities were found to be complementary for the Dutch Roll mode, but not for the short-period mode. Regions of optimal ride and handling qualities are defined for the short-period mode, and the effects of turbulence levels studied.

  1. Orion Entry Handling Qualities Assessments

    NASA Technical Reports Server (NTRS)

    Bihari, B.; Tiggers, M.; Strahan, A.; Gonzalez, R.; Sullivan, K.; Stephens, J. P.; Hart, J.; Law, H., III; Bilimoria, K.; Bailey, R.

    2011-01-01

    The Orion Command Module (CM) is a capsule designed to bring crew back from the International Space Station (ISS), the moon and beyond. The atmospheric entry portion of the flight is deigned to be flown in autopilot mode for nominal situations. However, there exists the possibility for the crew to take over manual control in off-nominal situations. In these instances, the spacecraft must meet specific handling qualities criteria. To address these criteria two separate assessments of the Orion CM s entry Handling Qualities (HQ) were conducted at NASA s Johnson Space Center (JSC) using the Cooper-Harper scale (Cooper & Harper, 1969). These assessments were conducted in the summers of 2008 and 2010 using the Advanced NASA Technology Architecture for Exploration Studies (ANTARES) six degree of freedom, high fidelity Guidance, Navigation, and Control (GN&C) simulation. This paper will address the specifics of the handling qualities criteria, the vehicle configuration, the scenarios flown, the simulation background and setup, crew interfaces and displays, piloting techniques, ratings and crew comments, pre- and post-fight briefings, lessons learned and changes made to improve the overall system performance. The data collection tools, methods, data reduction and output reports will also be discussed. The objective of the 2008 entry HQ assessment was to evaluate the handling qualities of the CM during a lunar skip return. A lunar skip entry case was selected because it was considered the most demanding of all bank control scenarios. Even though skip entry is not planned to be flown manually, it was hypothesized that if a pilot could fly the harder skip entry case, then they could also fly a simpler loads managed or ballistic (constant bank rate command) entry scenario. In addition, with the evaluation set-up of multiple tasks within the entry case, handling qualities ratings collected in the evaluation could be used to assess other scenarios such as the constant bank angle

  2. Ride quality sensitivity to SAS control law and to handling quality variations

    NASA Technical Reports Server (NTRS)

    Roberts, P. A.; Schmidt, D. K.; Swaim, R. L.

    1976-01-01

    The RQ trends which large flexible aircraft exhibit under various parameterizations of control laws and handling qualities are discussed. A summary of the assumptions and solution technique, a control law parameterization review, a discussion of ride sensitivity to handling qualities, and the RQ effects generated by implementing relaxed static stability configurations are included.

  3. A Look at Handling Qualities of Canard Configurations

    NASA Technical Reports Server (NTRS)

    Anderson, Seth B.

    1986-01-01

    The first human-powered flight was achieved by a canard-configured aircraft (Wright Brothers). Although other canard concepts were flown with varying degrees of success over the years, the tail-aft configuration has dominated the aircraft market for both military and civil use. Reviewed are the development of several canard aircraft with emphasis on stability and control, handling qualities, and operating problems. The results show that early canard concepts suffered adversely in flight behavior because of a lack of understanding of the sensitivities of these concepts to basic stability and control principles. Modern canard designs have been made competitive with tail-aft configurations by using appropriate handling qualities design criteria.

  4. Subsonic Wing Optimization for Handling Qualities Using ACSYNT

    NASA Technical Reports Server (NTRS)

    Soban, Danielle Suzanne

    1996-01-01

    The capability to accurately and rapidly predict aircraft stability derivatives using one comprehensive analysis tool has been created. The PREDAVOR tool has the following capabilities: rapid estimation of stability derivatives using a vortex lattice method, calculation of a longitudinal handling qualities metric, and inherent methodology to optimize a given aircraft configuration for longitudinal handling qualities, including an intuitive graphical interface. The PREDAVOR tool may be applied to both subsonic and supersonic designs, as well as conventional and unconventional, symmetric and asymmetric configurations. The workstation-based tool uses as its model a three-dimensional model of the configuration generated using a computer aided design (CAD) package. The PREDAVOR tool was applied to a Lear Jet Model 23 and the North American XB-70 Valkyrie.

  5. Aircraft Cabin Environmental Quality Sensors

    SciTech Connect

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

    2010-05-06

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

  6. A design procedure and handling quality criteria for lateral directional flight control systems

    NASA Technical Reports Server (NTRS)

    Stein, G.; Henke, A. H.

    1972-01-01

    A practical design procedure for aircraft augmentation systems is described based on quadratic optimal control technology and handling-quality-oriented cost functionals. The procedure is applied to the design of a lateral-directional control system for the F4C aircraft. The design criteria, design procedure, and final control system are validated with a program of formal pilot evaluation experiments.

  7. Rotorcraft handling-qualities design criteria development

    NASA Technical Reports Server (NTRS)

    Aiken, Edwin W.; Lebacqz, J. Victor; Chen, Robert T. N.; Key, David L.

    1988-01-01

    Joint NASA/Army efforts at the Ames Research Center to develop rotorcraft handling-qualities design criteria began in earnest in 1975. Notable results were the UH-1H VSTOLAND variable stability helicopter, the VFA-2 camera-and-terrain-board simulator visual system, and the generic helicopter real-time mathematical model, ARMCOP. An initial series of handling-qualities studies was conducted to assess the effects of rotor design parameters, interaxis coupling, and various levels of stability and control augmentation. The ability to conduct in-flight handling-qualities research was enhanced by the development of the NASA/Army CH-47 variable-stability helicopter. Research programs conducted using this vehicle include vertical-response investigations, hover augmentation systems, and the effects of control-force characteristics. The handling-qualities data base was judged to be sufficient to allow an update of the military helicopter handling-qualities specification, MIL-H-8501. These efforts, including not only the in-house experimental work but also contracted research and collaborative programs performed under the auspices of various international agreements. The report concludes by reviewing the topics that are currently most in need of work, and the plans for addressing these topics.

  8. Dynamic stability and handling qualities tests on a highly augmented, statically unstable airplane

    NASA Technical Reports Server (NTRS)

    Gera, Joseph; Bosworth, John T.

    1987-01-01

    Novel flight test and analysis techniques in the flight dynamics and handling qualities area are described. These techniques were utilized at NASA Ames-Dryden during the initial flight envelope clearance of the X-29A aircraft. It is shown that the open-loop frequency response of an aircraft with highly relaxed static stability can be successfully computed on the ground from telemetry data. Postflight closed-loop frequency response data were obtained from pilot-generated frequency sweeps and it is found that the current handling quality requirements for high-maneuverability aircraft are generally applicable to the X-29A.

  9. Handling Qualities of Large Rotorcraft in Hover and Low Speed

    NASA Technical Reports Server (NTRS)

    Malpica, Carlos; Theodore, Colin R.; Lawrence , Ben; Blanken, Chris L.

    2015-01-01

    According to a number of system studies, large capacity advanced rotorcraft with a capability of high cruise speeds (approx.350 mph) as well as vertical and/or short take-off and landing (V/STOL) flight could alleviate anticipated air transportation capacity issues by making use of non-primary runways, taxiways, and aprons. These advanced aircraft pose a number of design challenges, as well as unknown issues in the flight control and handling qualities domains. A series of piloted simulation experiments have been conducted on the NASA Ames Research Center Vertical Motion Simulator (VMS) in recent years to systematically investigate the fundamental flight control and handling qualities issues associated with the characteristics of large rotorcraft, including tiltrotors, in hover and low-speed maneuvering.

  10. Handling Qualities Evaluations of Unmanned Aircraft Systems

    DTIC Science & Technology

    2015-05-04

    limit to how large the delta can be. For example, if the error limit is ±10° for pitch , an input of +20° pitch from a 0° pitch angle will result in the...indicates feedback pitch attitude. Using the pitch ladders, establish two zones UP and DOWN, which are between 0° and 5° pitch , positive and negative...the Pitch Axis Begin the maneuver in level flight then with low frequency inputs maneuver to either the UP or DOWN boundary, as called by the test

  11. Statistical survey of XB-70 airplane responses and control usage with an illustration of the application to handling qualities criteria

    NASA Technical Reports Server (NTRS)

    Powers, B. G.

    1972-01-01

    The magnitude and frequency of occurrence of aircraft responses and control inputs during 27 flights of the XB-70 airplane were measured. Exceedance curves are presented for the airplane responses and control usage. A technique is presented which makes use of these exceedance curves to establish or verify handling qualities criteria. This technique can provide a means of incorporating current operational experience in handling qualities requirements for future aircraft.

  12. Emissions of NOx, particle mass and particle numbers from aircraft main engines, APU's and handling equipment at Copenhagen Airport

    NASA Astrophysics Data System (ADS)

    Winther, Morten; Kousgaard, Uffe; Ellermann, Thomas; Massling, Andreas; Nøjgaard, Jacob Klenø; Ketzel, Matthias

    2015-01-01

    This paper presents a detailed emission inventory for NOx, particle mass (PM) and particle numbers (PN) for aircraft main engines, APU's and handling equipment at Copenhagen Airport (CPH) based on time specific activity data and representative emission factors for the airport. The inventory has a high spatial resolution of 5 m × 5 m in order to be suited for further air quality dispersion calculations. Results are shown for the entire airport and for a section of the airport apron area ("inner apron") in focus. The methodology presented in this paper can be used to quantify the emissions from aircraft main engines, APU and handling equipment in other airports. For the entire airport, aircraft main engines is the largest source of fuel consumption (93%), NOx, (87%), PM (61%) and PN (95%). The calculated fuel consumption [NOx, PM, PN] shares for APU's and handling equipment are 5% [4%, 8%, 5%] and 2% [9%, 31%, 0%], respectively. At the inner apron area for handling equipment the share of fuel consumption [NOx, PM, PN] are 24% [63%, 75%, 2%], whereas APU and main engines shares are 43% [25%, 19%, 54%], and 33% [11%, 6%, 43%], respectively. The inner apron NOx and PM emission levels are high for handling equipment due to high emission factors for the diesel fuelled handling equipment and small for aircraft main engines due to small idle-power emission factors. Handling equipment is however a small PN source due to the low number based emission factors. Jet fuel sulphur-PM sensitivity calculations made in this study with the ICAO FOA3.0 method suggest that more than half of the PM emissions from aircraft main engines at CPH originate from the sulphur content of the fuel used at the airport. Aircraft main engine PN emissions are very sensitive to the underlying assumptions. Replacing this study's literature based average emission factors with "high" and "low" emission factors from the literature, the aircraft main engine PN emissions were estimated to change with a

  13. Handling Qualities of Model Reference Adaptive Controllers with Varying Complexity for Pitch-Roll Coupled Failures

    NASA Technical Reports Server (NTRS)

    Schaefer, Jacob; Hanson, Curt; Johnson, Marcus A.; Nguyen, Nhan

    2011-01-01

    Three model reference adaptive controllers (MRAC) with varying levels of complexity were evaluated on a high performance jet aircraft and compared along with a baseline nonlinear dynamic inversion controller. The handling qualities and performance of the controllers were examined during failure conditions that induce coupling between the pitch and roll axes. Results from flight tests showed with a roll to pitch input coupling failure, the handling qualities went from Level 2 with the baseline controller to Level 1 with the most complex MRAC tested. A failure scenario with the left stabilator frozen also showed improvement with the MRAC. Improvement in performance and handling qualities was generally seen as complexity was incrementally added; however, added complexity usually corresponds to increased verification and validation effort required for certification. The tradeoff between complexity and performance is thus important to a controls system designer when implementing an adaptive controller on an aircraft. This paper investigates this relation through flight testing of several controllers of vary complexity.

  14. Handling Qualities Influences on Civil Tiltrotor Terminal Operating Procedure Development

    NASA Technical Reports Server (NTRS)

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

    1994-01-01

    The potential for tiltrotor aircraft as civil transports has been well recognized. Realization of that potential requires development of operating procedures tailored to take advantage of the tiltrotor's capabilities, including thrust vectoring independent of body pitch attitude and good low-speed control. While the tiltrotor shares flight characteristics with both fixed wing airplanes and helicopters, it must convert between those flight modes, typically within the context of precise terminal operations. A series of piloted simulation experiments has been conducted on the NASA Ames Research Center Vertical Motion Simulator (VMS) to investigate the influence of tiltrotor cockpit design features on developing certification and operating criteria for civil tiltrotor transports. Handling qualities evaluations have shaped cockpit design guidelines and operating procedure development for a civil tiltrotor. In particular, four topics demonstrate the interplay of handling qualities and operations profile in the development of terminal operating procedures and cockpit or control equipment for a civil tiltrotor: conversion (airplane to helicopter mode), final approach path angle, operating profile speeds and speed changes (particularly under instrument conditions), and one engine inoperative operational considerations.

  15. Pre-slaughter handling and pork quality.

    PubMed

    Vermeulen, L; Van de Perre, V; Permentier, L; De Bie, S; Verbeke, G; Geers, R

    2015-02-01

    Environmental variables, as sound levels, were collected during the pre-slaughter process in 18 different Belgian commercial slaughterhouses. Four pre-slaughter phases were determined: firstly after arrival of the truck at the slaughterhouse and just before unloading, secondly during unloading, thirdly at lairage and finally while moving to the stunner. A total of 8508 pigs was examined during the pre-slaughter process, of which the pH(LT) (M. longissimus thoracis), at 30 min post-mortem was measured. For each pre-slaughter phase, variables which might influence pork quality were determined. Moreover, this study made it possible to infer a checklist to represent and predict PSE traits of pork for all kind of pre-slaughter situations. The checklist shows also that the impact on pork quality is more decisive for the variables measured close to the stunning phase. Hence, this information is useful for the industry to optimize handling of pigs, reducing the risk for PSE traits.

  16. Orion Capsule Handling Qualities for Atmospheric Entry

    NASA Technical Reports Server (NTRS)

    Tigges, Michael A.; Bihari, Brian D.; Stephens, John-Paul; Vos, Gordon A.; Bilimoria, Karl D.; Mueller, Eric R.; Law, Howard G.; Johnson, Wyatt; Bailey, Randall E.; Jackson, Bruce

    2011-01-01

    Two piloted simulations were conducted at NASA's Johnson Space Center using the Cooper-Harper scale to study the handling qualities of the Orion Command Module capsule during atmospheric entry flight. The simulations were conducted using high fidelity 6-DOF simulators for Lunar Return Skip Entry and International Space Station Return Direct Entry flight using bank angle steering commands generated by either the Primary (PredGuid) or Backup (PLM) guidance algorithms. For both evaluations, manual control of bank angle began after descending through Entry Interface into the atmosphere until drogue chutes deployment. Pilots were able to use defined bank management and reversal criteria to accurately track the bank angle commands, and stay within flight performance metrics of landing accuracy, g-loads, and propellant consumption, suggesting that the pilotability of Orion under manual control is both achievable and provides adequate trajectory performance with acceptable levels of pilot effort. Another significant result of these analyses is the applicability of flying a complex entry task under high speed entry flight conditions relevant to the next generation Multi Purpose Crew Vehicle return from Mars and Near Earth Objects.

  17. Flying qualities criteria for superaugmented aircraft

    NASA Technical Reports Server (NTRS)

    Berry, D. T.

    1984-01-01

    An overview of Dryden superaugmented aircraft flying qualities research is presented. This includes F-8 digital fly by wire flight experiments, orbiter flying qualities, shuttle improvements, AFTI/F-16, flying qualities and control system alternatives, Vertical Motion Simulator Shuttle evaluation and Total in Flight Simulator pitch rate criteria.

  18. Effects of aircraft design on STOL ride quality: A simulator study

    NASA Technical Reports Server (NTRS)

    Jacobson, I. D.; Jones, C. R.

    1974-01-01

    To improve the ride quality in short takeoff aircraft, several means have been investigated. In general, these methods consist of placing sensors in the aircraft which sense aircraft motion, usually linear accelerations and angular rates. These signals are then used to deflect control surfaces which generate aerodynamic forces and moments which tend to minimize the motion which the passenger feels. One of the disadvantages of some of these systems is that they may tend to degrade the handling qualities or controllability of the airplane, making it more difficult or annoying for the pilot to fly. Rather than using active control systems to control ride quality, one might possibly design aircraft so that they are inherently pleasant to ride. The purpose of this study is to determine the relationship between characteristic aircraft motions and aircraft ride quality.

  19. Nonlinear programming in design of control systems with specified handling qualities.

    NASA Technical Reports Server (NTRS)

    Schy, A. A.

    1972-01-01

    A method is described for using nonlinear programing in the computer-aided design of aircraft control systems. It is assumed that the quality of such systems depends on many criteria. These criteria are included in the constraints vector, and the design proceeds through a sequence of nonlinear programing solutions in which the designer varies the specification of sets of requirements levels. The method is applied to design of a lateral stability augmentation system (SAS) for a fighter aircraft, in which the requirements vector is chosen from the official handling-qualities specifications. Results are shown for several simple SAS configurations designed to obtain desirable handling qualities over all design flight conditions with minimum feedback gains.

  20. Incorporating Handling Qualities Analysis into Rotorcraft Conceptual Design

    NASA Technical Reports Server (NTRS)

    Lawrence, Ben

    2014-01-01

    This paper describes the initial development of a framework to incorporate handling qualities analyses into a rotorcraft conceptual design process. In particular, the paper describes how rotorcraft conceptual design level data can be used to generate flight dynamics models for handling qualities analyses. Also, methods are described that couple a basic stability augmentation system to the rotorcraft flight dynamics model to extend analysis to beyond that of the bare airframe. A methodology for calculating the handling qualities characteristics of the flight dynamics models and for comparing the results to ADS-33E criteria is described. Preliminary results from the application of the handling qualities analysis for variations in key rotorcraft design parameters of main rotor radius, blade chord, hub stiffness and flap moment of inertia are shown. Varying relationships, with counteracting trends for different handling qualities criteria and different flight speeds are exhibited, with the action of the control system playing a complex part in the outcomes. Overall, the paper demonstrates how a broad array of technical issues across flight dynamics stability and control, simulation and modeling, control law design and handling qualities testing and evaluation had to be confronted to implement even a moderately comprehensive handling qualities analysis of relatively low fidelity models. A key outstanding issue is to how to 'close the loop' with an overall design process, and options for the exploration of how to feedback handling qualities results to a conceptual design process are proposed for future work.

  1. Handling Qualities Results of an Initial Geared Flap Tilt Wing Piloted Simulation

    NASA Technical Reports Server (NTRS)

    Guerrero, Lourdes M.; Corliss, Lloyd D.

    1991-01-01

    An exploratory simulation study of a novel approach to pitch control for a tilt wing aircraft was conducted in 1990 on the NASA-Ames Vertical Motion Simulator. The purpose of the study was to evaluate and compare the handling qualities of both a conventional and a geared flap tilt wing control configuration. The geared flap is an innovative control concept which has the potential for reducing or eliminating the horizontal pitch control tail rotor or reaction jets required by prior tilt wing designs. The handling qualities results of the geared flap control configuration are presented in this paper and compared to the conventional (programmed flap) tilt wing control configuration. This paper also describes the geared flap concept, the tilt wing aircraft, the simulation model, the simulation facility and experiment setup, and the pilot evaluation tasks and procedures.

  2. Dynamic stability and handling qualities tests on a highly augmented, statically unstable airplane

    NASA Technical Reports Server (NTRS)

    Gera, Joseph; Bosworth, John T.

    1987-01-01

    This paper describes some novel flight tests and analysis techniques in the flight dynamics and handling qualities area. These techniques were utilized during the initial flight envelope clearance of the X-29A aircraft and were largely responsible for the completion of the flight controls clearance program without any incidents or significant delays. The resulting open-loop and closed-loop frequency responses and the time history comparison using flight and linear simulation data are discussed.

  3. Flight testing and frequency domain analysis for rotorcraft handling qualities characteristics

    NASA Technical Reports Server (NTRS)

    Ham, Johnnie A.; Gardner, Charles K.; Tischler, Mark B.

    1993-01-01

    A demonstration of frequency domain flight testing techniques and analyses was performed on a U.S. Army OH-58D helicopter in support of the OH-58D Airworthiness and Flight Characteristics Evaluation and the Army's development and ongoing review of Aeronautical Design Standard 33C, Handling Qualities Requirements for Military Rotorcraft. Hover and forward flight (60 knots) tests were conducted in 1 flight hour by Army experimental test pilots. Further processing of the hover data generated a complete database of velocity, angular rate, and acceleration frequency responses to control inputs. A joint effort was then undertaken by the Airworthiness Qualification Test Directorate (AQTD) and the U.S. Army Aeroflightdynamics Directorate (AFDD) to derive handling qualities information from the frequency response database. A significant amount of information could be extracted from the frequency domain database using a variety of approaches. This report documents numerous results that have been obtained from the simple frequency domain tests; in many areas, these results provide more insight into the aircraft dynamics that affect handling qualities than to traditional flight tests. The handling qualities results include ADS-33C bandwidth and phase delay calculations, vibration spectral determinations, transfer function models to examine single axis results, and a six degree of freedom fully coupled state space model. The ability of this model to accurately predict aircraft responses was verified using data from pulse inputs. This report also documents the frequency-sweep flight test technique and data analysis used to support the tests.

  4. Effects of simulator motion and visual characteristics on rotorcraft handling qualities evaluations

    NASA Technical Reports Server (NTRS)

    Mitchell, David G.; Hart, Daniel C.

    1993-01-01

    The pilot's perceptions of aircraft handling qualities are influenced by a combination of the aircraft dynamics, the task, and the environment under which the evaluation is performed. When the evaluation is performed in a groundbased simulator, the characteristics of the simulation facility also come into play. Two studies were conducted on NASA Ames Research Center's Vertical Motion Simulator to determine the effects of simulator characteristics on perceived handling qualities. Most evaluations were conducted with a baseline set of rotorcraft dynamics, using a simple transfer-function model of an uncoupled helicopter, under different conditions of visual time delays and motion command washout filters. Differences in pilot opinion were found as the visual and motion parameters were changed, reflecting a change in the pilots' perceptions of handling qualities, rather than changes in the aircraft model itself. The results indicate a need for tailoring the motion washout dynamics to suit the task. Visual-delay data are inconclusive but suggest that it may be better to allow some time delay in the visual path to minimize the mismatch between visual and motion, rather than eliminate the visual delay entirely through lead compensation.

  5. Indoor air quality investigation on commercial aircraft.

    PubMed

    Lee, S C; Poon, C S; Li, X D; Luk, F

    1999-09-01

    Sixteen flights had been investigated for indoor air quality (IAQ) on Cathay Pacific aircraft from June 1996 to August 1997. In general, the air quality on Cathay Pacific aircraft was within relevant air quality standards because the average age of aircraft was less than 2 years. Carbon dioxide (CO2) levels on all flights measured were below the Federal Aviation Administration (FAA) standard (30,000 ppm). The CO2 level was substantially higher during boarding and de-boarding than cruise due to low fresh air supply. Humidity on the aircraft was low, especially for long-haul flights. Minimum humidity during cruise was below the American Society of Heating, Refrigerating, and Air-Conditioning Engineers (ASHRAE) minimum humidity standard (20%). The average temperature was within a comfortable temperature range of 23 +/- 2 degrees C. The vertical temperature profile on aircraft was uniform and below the International Standard Organization (ISO) standard. Carbon monoxide levels were below the FAA standard (50 ppm). Trace amount of ozone detected ranged from undetectable to 90 ppb, which was below the FAA standard. Particulate level was low for most non-smoking flights, but peaks were observed during boarding and de-boarding. The average particulate level in smoking flights (138 micrograms/m3) was higher than non-smoking flights (7.6 micrograms/m3). The impact on IAQ by switching from low-mode to high-mode ventilation showed a reduction in CO2 levels, temperature, and relative humidity.

  6. Review of US Navy VSTOL handling qualities requirements

    NASA Technical Reports Server (NTRS)

    Hutchings, D. E.

    1977-01-01

    Handling qualities requirements for V/STOL operations from small ships are considered in terms of the ship operating environment. Turbulence, wind over the deck, ship motion, visibility, and severe weather and sea conditions are among the factors discussed.

  7. Analytical study of ride smoothing benefits of control system configurations optimized for pilot handling qualities

    NASA Technical Reports Server (NTRS)

    Powers, B. G.

    1978-01-01

    An analytical study was conducted to evaluate the relative improvements in aircraft ride qualities that resulted from utilizing several control law configurations that were optimized for pilot handling qualities only. The airplane configuration used was an executive jet transport in the approach configuration. The control law configurations included the basic system, a rate feedback system, three command augmentation systems (rate command, attitude command, and rate command/attitude hold), and a control wheel steering system. Both the longitudinal and lateral directional axes were evaluated. A representative example of each control law configuration was optimized for pilot handling qualities on a fixed base simulator. The root mean square airplane responses to turbulence were calculated, and predictions of ride quality ratings were computed by using three models available in the literature.

  8. Orion Handling Qualities During ISS Proximity Operations and Docking

    NASA Technical Reports Server (NTRS)

    Stephens, John-Paul; Vos, Gordon A.; Bilimoria, Karl D.; Mueller, Eric R.; Brazzel, Jack; Spehar, Pete

    2011-01-01

    NASA's Orion spacecraft is designed to autonomously rendezvous and dock with many vehicles including the International Space Station. However, the crew is able to assume manual control of the vehicle s attitude and flight path. In these instances, Orion must meet handling qualities requirements established by NASA. Two handling qualities assessments were conducted at the Johnson Space Center to evaluate preliminary designs of the vehicle using a six degree of freedom, high-fidelity guidance, navigation, and control simulation. The first assessed Orion s handling qualities during the last 20 ft before docking, and included both steady and oscillatory motions of the docking target. The second focused on manual acquisition of the docking axis during the proximity operations phase and subsequent station-keeping. Cooper-Harper handling qualities ratings, workload ratings and comments were provided by 10 evaluation pilots for the docking study and 5 evaluation pilots for the proximity operations study. For the docking task, both cases received 90% Level 1 (satisfactory) handling qualities ratings, exceeding NASA s requirement. All ratings for the ProxOps task were Level 1. These evaluations indicate that Orion is on course to meet NASA's handling quality requirements for ProxOps and docking.

  9. Getting a Handle on Academic Quality

    ERIC Educational Resources Information Center

    Massy, William F.; Graham, Steven W.; Short, Paula Myrick

    2007-01-01

    The quality of teaching, more than ever, is seen as the all-important results area for colleges and universities. Few board members would dispute the importance of teaching or their responsibility for exercising oversight over its quality and continuous improvement. Yet there is little consensus about how to accomplish such oversight. Few board…

  10. Developing a workstation-based, real-time simulation for rapid handling qualities evaluations during design

    NASA Technical Reports Server (NTRS)

    Anderson, Frederick; Biezad, Daniel J.

    1994-01-01

    This paper describes the Rapid Aircraft DynamIcs AssessmeNt (RADIAN) project - an integration of the Aircraft SYNThesis (ACSTNT) design code with the USAD DATCOM code that estimates stability derivatives. Both of these codes are available to universities. These programs are then linked to flight simulation and flight controller synthesis tools and resulting design is evaluated on a graphics workstation. The entire process reduces the preliminary design time by an order of magnitude and provides an initial handling qualities evaluation of the design coupled to a control law. The integrated design process is applicable to both conventional aircraft taken from current textbooks and to unconventional designs emphasizing agility and propulsive control of attitude. The interactive and concurrent nature of the design process has been well received by industry and by design engineers at NASA. The process is being implemented into the design curriculum and is being used by students who view it as a significant advance over prior methods.

  11. An Investigation of Large Tilt-Rotor Hover and Low Speed Handling Qualities

    NASA Technical Reports Server (NTRS)

    Malpica, Carlos A.; Decker, William A.; Theodore, Colin R.; Lindsey, James E.; Lawrence, Ben; Blanken, Chris L.

    2011-01-01

    A piloted simulation experiment conducted on the NASA-Ames Vertical Motion Simulator evaluated the hover and low speed handling qualities of a large tilt-rotor concept, with particular emphasis on longitudinal and lateral position control. Ten experimental test pilots evaluated different combinations of Attitude Command-Attitude Hold (ACAH) and Translational Rate Command (TRC) response types, nacelle conversion actuator authority limits and inceptor choices. Pilots performed evaluations in revised versions of the ADS-33 Hover, Lateral Reposition and Depart/Abort MTEs and moderate turbulence conditions. Level 2 handling qualities ratings were primarily recorded using ACAH response type in all three of the evaluation maneuvers. The baseline TRC conferred Level 1 handling qualities in the Hover MTE, but there was a tendency to enter into a PIO associated with nacelle actuator rate limiting when employing large, aggressive control inputs. Interestingly, increasing rate limits also led to a reduction in the handling qualities ratings. This led to the identification of a nacelle rate to rotor longitudinal flapping coupling effect that induced undesired, pitching motions proportional to the allowable amount of nacelle rate. A modification that counteracted this effect significantly improved the handling qualities. Evaluation of the different response type variants showed that inclusion of TRC response could provide Level 1 handling qualities in the Lateral Reposition maneuver by reducing coupled pitch and heave off axis responses that otherwise manifest with ACAH. Finally, evaluations in the Depart/Abort maneuver showed that uncertainty about commanded nacelle position and ensuing aircraft response, when manually controlling the nacelle, demanded high levels of attention from the pilot. Additional requirements to maintain pitch attitude within 5 deg compounded the necessary workload.

  12. Ride quality systems for commuter aircraft

    NASA Technical Reports Server (NTRS)

    Downing, D. R.; Hammond, T. A.; Amin, S. P.

    1983-01-01

    The state-of-the-art in Active Ride Augmentation, specifically in terms of its feasibility for commuter aircraft applications. A literature survey was done, and the principal results are presented here through discussion of different Ride Quality Augmentation System (RQAS) designs and advances in related technologies. Recommended follow-on research areas are discussed, and a preliminary RQAS configuration for detailed design and development is proposed.

  13. In Flight Evaluation of Active Inceptor Force-Feel Characteristics and Handling Qualities

    NASA Technical Reports Server (NTRS)

    Lusardi, Jeff A.; Blanken, Chris L.; Ott, Carl Raymond; Malpica, Carlos A.; von Gruenhagen, Wolfgang

    2012-01-01

    The effect of inceptor feel-system characteristics on piloted handling qualities has been a research topic of interest for many years. Most of the research efforts have focused on advanced fly-by-wire fixed-wing aircraft with only a few studies investigating the effects on rotorcraft. Consequently, only limited guidance is available on how cyclic force-feel characteristics should be set to obtain optimal handling qualities for rotorcraft. To study this effect, the U.S. Army Aeroflightdynamics Directorate working with the DLR Institute of Flight Systems in Germany under Task X of the U.S. German Memorandum of Understanding have been conducting flight test evaluations. In the U.S., five experimental test pilots have completed evaluations of two Mission Task Elements (MTEs) from ADS-33E-PRF and two command/response types for a matrix of center-stick cyclic force-feel characteristics at Moffett Field. In Germany, three experimental test Pilots have conducted initial evaluations of the two MTEs with two command/response types for a parallel matrix of side-stick cyclic force-feel characteristics at WTD-61 in Manching. The resulting data set is used to correlate the effect of changes in natural frequency and damping ratio of the cyclic inceptor on the piloted handling qualities. Existing criteria in ADS-33E and a proposed Handling Qualities Sensitivity Function that includes the effects of the cyclic force-feel characteristics are also evaluated against the data set and discussed.

  14. Results of an A109 simulation validation and handling qualities study

    NASA Technical Reports Server (NTRS)

    Eshow, Michelle M.; Orlandi, Diego; Bonaita, Giovanni; Barbieri, Sergio

    1989-01-01

    The results for the validation of a mathematical model of the Agusta A109 helicopter, and subsequent use of the model as the baseline for a handling qualities study of cockpit centerstick requirements, are described. The technical approach included flight test, non-realtime analysis, and realtime piloted simulation. Results of the validation illustrate a time- and frequency-domain approach to the model and simulator issues. The final A109 model correlates well with the actual aircraft with the Stability Augmentation System (SAS) engaged, but is unacceptable without the SAS because of instability and response coupling at low speeds. Results of the centerstick study support the current U.S. Army handling qualities requirements for centerstick characteristics.

  15. Simulation evaluation of the effects of time delay and motion on rotorcraft handling qualities

    NASA Technical Reports Server (NTRS)

    Mitchell, David G.; Hoh, Roger H.; Atencio, Adolph, Jr.; Key, David L.

    1991-01-01

    A study aimed at determining the effects of simulator characteristics on perceived handling qualities is discussed. Evaluations were conducted with a baseline set of rotorcraft dynamics, using a simple transfer-function model of an uncoupled helicopter, under different conditions of visual and overall time delays. As the visual and motion parameters were changed, differences in pilot opinion were found reflecting a change in the pilots' perceptions of handling qualities, rather than changes in the aircraft model itself. It is concluded that it is necessary to tailor the motion washout dynamics to suit the task, with reduced washouts for precision maneuvering as compared to aggressive maneuvering. Visual-delay data suggest that it may be better to allow some time delay in the visual path to minimize the mismatch between visual and motion, rather than eliminate the visual delay entirely through lead compensation.

  16. Evaluation of High-Angle-of-Attack Handling Qualities for the X-31A Using Standard Evaluation Maneuvers

    NASA Technical Reports Server (NTRS)

    Stoliker, Patrick C.; Bosworth, John T.

    1996-01-01

    The X-31A aircraft gross-acquisition and fine-tracking handling qualities have been evaluated using standard evaluation maneuvers developed by Wright Laboratory, Wright-Patterson Air Force Base. The emphasis of the testing is in the angle-of-attack range between 30 deg and 70 deg. Longitudinal gross-acquisition handling qualities results show borderline Level 1/Level 2 performance. Lateral gross-acquisition testing results in Level 1/Level 2 ratings below 45 deg angle of attack, degrading into Level 3 as angle of attack increases. The fine-tracking performance in both longitudinal and lateral axes also receives Level 1 ratings near 30 deg angle of attack, with the ratings tending towards Level 3 at angles of attack greater than 50 deg. These ratings do not match the expectations from the extensive close-in combat testing where the X-31A aircraft demonstrated fair to good handling qualities maneuvering for high angles of attack. This paper presents the results of the high-angle-of-attack handling qualities flight testing of the X-31A aircraft. Discussion of the preparation for the maneuvers, the pilot ratings, and selected pilot comments are included. Evaluation of the results is made in conjunction with existing Neal-Smith, bandwidth, Smith-Geddes, and military specifications.

  17. Exploratory piloted simulator study of the effects of winglets on handling qualities of a representative agricultural airplane

    NASA Technical Reports Server (NTRS)

    Ogburn, M. E.; Brown, P. W.

    1980-01-01

    The effects on handling qualities of adding winglets to a representative agricultural aircraft configuration during swath-run maneuvering were evaluated. Aerodynamic data used in the simulation were based on low-speed wind tunnel tests of a full scale airplane and a subscale model. The Cooper-Harper handling qualities rating scale, supplementary pilot comments, and pilot vehicle performance data were used to describe the handling qualities of the airplane with the different wing-tip configurations. Results showed that the lateral-directional handling qualities of the airplane were greatly affected by the application of winglets and winglet cant angle. The airplane with winglets canted out 20 deg exhibited severely degraded lateral directional handling qualities in comparison to the basic airplane. When the winglets were canted inward 10 deg, the flying qualities of the configuration were markedly improved over those of the winglet-canted-out configuration or the basic configuration without winglets, indicating that proper tailoring of the winglet design may afford a potential benefit in the area of handling qualities.

  18. Passenger ride quality in transport aircraft

    NASA Technical Reports Server (NTRS)

    Jacobson, I. D.; Kuhlthau, A. R.; Richards, L. G.; Conner, D. W.

    1978-01-01

    Quantitative relationships are presented which can be used to account for passenger ride quality in transport aircraft. These relations can be used to predict passenger comfort and satisfaction under a variety of flight conditions. Several applications are detailed, including evaluation of use of spoilers to attenuate trailing vortices, identifying key elements in a complex maneuver which leads to discomfort, determining noise/motion tradeoffs, evaluating changes in wing loading, and others. Variables included in the models presented are motion, noise, temperature, pressure, and seating.

  19. Handling Qualities Flight Testing of the Stratospheric Observatory for Infrared Astronomy (SOFIA)

    NASA Technical Reports Server (NTRS)

    Glaser, Scott T.; Strovers, Brian K.

    2011-01-01

    Airborne infrared astronomy has a long successful history, albeit relatively unknown outside of the astronomy community. A major problem with ground based infrared astronomy is the absorption and scatter of infrared energy by water in the atmosphere. Observing the universe from above 40,000 ft puts the observation platform above 99% of the water vapor in the atmosphere, thereby addressing this problem at a fraction of the cost of space based systems. The Stratospheric Observatory For Infrared Astronomy (SOFIA) aircraft is the most ambitious foray into the field of airborne infrared astronomy in history. Using a 747SP (The Boeing Company, Chicago, Illinois) aircraft modified with a 2.5m telescope located in the aft section of the fuselage, the SOFIA endeavors to provide views of the universe never before possible and at a fraction of the cost of space based systems. The modification to the airplane includes moveable doors and aperture that expose the telescope assembly. The telescope assembly is aimed and stabilized using a multitude of on board systems. This modification has the potential to cause aerodynamic anomalies that could induce undesired forces either at the cavity itself or indirectly due to interference with the empennage, both of which could cause handling qualities issues. As a result, an extensive analysis and flight test program was conducted from December 2009 through March 2011. Several methods, including a Lower Order Equivalent Systems analysis and pilot assessment, were used to ascertain the effects of the modification. The SOFIA modification was found to cause no adverse handling qualities effects and the aircraft was cleared for operational use. This paper discusses the history and modification to the aircraft, development of test procedures and analysis, results of testing and analysis, lessons learned for future projects and justification for operational certification.

  20. The use of ground based simulation for handling qualities research: A new assessment

    NASA Technical Reports Server (NTRS)

    Mitchell, David G.; Hoh, Roger H.; Atencio, Adolph, Jr.; Key, David L.

    1992-01-01

    A study was conducted on the NASA Ames Research Center's Vertical Motion Simulator to determine the effects of simulator characteristics on perceived handling characteristics. Differences in pilot opinion were found as the visual and motion parameters were changed, reflecting a change in the pilots' perceptions of handling qualities, rather than changes in the aircraft model itself. The results indicate a need for tailoring the motion without dynamics to suit the task, with reduced washouts for precision maneuvering as compared to aggressive maneuvering. Visual delay data are inconclusive, but suggest that it may be better to allow some time delay in the visual path to minimize the mismatch between vision and motion, rather than eliminate the visual delay entirely through lead compensation. The simulation results are compared with ratings from a similar in-flight simulation experiment.

  1. Flexible aircraft flying and ride qualities

    NASA Technical Reports Server (NTRS)

    Ashkenas, I. L.; Magdaleno, R. E.; Mcruer, D. T.

    1984-01-01

    A brief analytic exposition is presented to illustrate a central principle in flexible mode control, some of the pertinent pilot centered requirements are listed and discussed. The desired features of the control methodology are exposed and the methodology to be used is selected. The example Boeing supplied characteristics are discussed and approximated with a reduced order model and a simplified treatment of unsteady aerodynamics. The closed loop flight control system design follows, along with first level assessments of resulting handling and ride quality characteristics. Some of these do not meet the postulated requirements and remain problems to be solved possibly by further analysis or future simulation.

  2. Ground-to-Flight Handling Qualities Comparisons for a High Performance Airplane

    NASA Technical Reports Server (NTRS)

    Brandon, Jay M.; Glaab, Louis J.; Brown, Philip W.; Phillips, Michael R.

    1995-01-01

    A flight test program was conducted in conjunction with a ground-based piloted simulation study to enable a comparison of handling qualities ratings for a variety of maneuvers between flight and simulation of a modern high performance airplane. Specific objectives included an evaluation of pilot-induced oscillation (PIO) tendencies and a determination of maneuver types which result in either good or poor ground-to-flight pilot handling qualities ratings. A General Dynamics F-16XL aircraft was used for the flight evaluations, and the NASA Langley Differential Maneuvering Simulator was employed for the ground based evaluations. Two NASA research pilots evaluated both the airplane and simulator characteristics using tasks developed in the simulator. Simulator and flight tests were all conducted within approximately a one month time frame. Maneuvers included numerous fine tracking evaluations at various angles of attack, load factors and speed ranges, gross acquisitions involving longitudinal and lateral maneuvering, roll angle captures, and an ILS task with a sidestep to landing. Overall results showed generally good correlation between ground and flight for PIO tendencies and general handling qualities comments. Differences in pilot technique used in simulator evaluations and effects of airplane accelerations and motions are illustrated.

  3. Directional handling qualities requirements for nap-of-the-earth tasks

    NASA Technical Reports Server (NTRS)

    Bivens, C. C.

    1986-01-01

    A piloted similator experiment designed to investigate directional axis handling qualities requirements for low-speed and hover tasks conducted by a scout/attack helicopter is described. Included were the directional characteristics of various candidate light helicopter family (LHX) configurations. The test also focused on conventional single main/tail rotor configurations where the first-order effects that contribute to the loss of tail rotor control experienced by the OH-58 series aircraft were modeled. Two types of yaw stability and control augmentation systems were implemented: washed-out yaw rate feedback and shaped control input, and a yaw rate command, heading-hold system. The results of the experiment indicate that rotorcraft configurations with high directional gust sensitivity require more yaw damping to maintain satisfactory handling qualities during nap-of-the-earth (NOE) flying tasks. It was also determined that both yaw damping and control response are critical handling qualities parameters in performing the air-to-air target acquisition and tracking task. The lack of substantial yaw damping and larger values of gust sensitivity increased the possibility of loss of directional control at low airspeeds for the tail rotor configurations.

  4. An Investigation of Large Tilt-Rotor Short-Term Attitude Response Handling Qualities Requirements in Hover

    NASA Technical Reports Server (NTRS)

    Malcipa, Carlos; Decker, William A.; Theodore, Colin R.; Blanken, Christopher L.; Berger, Tom

    2010-01-01

    A piloted simulation investigation was conducted using the NASA Ames Vertical Motion Simulator to study the impact of pitch, roll and yaw attitude bandwidth and phase delay on handling qualities of large tilt-rotor aircraft. Multiple bandwidth and phase delay pairs were investigated for each axis. The simulation also investigated the effect that the pilot offset from the center of gravity has on handling qualities. While pilot offset does not change the dynamics of the vehicle, it does affect the proprioceptive and visual cues and it can have an impact on handling qualities. The experiment concentrated on two primary evaluation tasks: a precision hover task and a simple hover pedal turn. Six pilots flew over 1400 data runs with evaluation comments and objective performance data recorded. The paper will describe the experiment design and methodology, discuss the results of the experiment and summarize the findings.

  5. The Effect of Load Factor on Aircraft Handling Qualities.

    DTIC Science & Technology

    1984-08-10

    C(S + 9) * SS 450 C8 (13) = C(S + 14) * CS * C(S + 9) + C(S * 13)) * S A * CA * CS * 8) * SS 466 CB(14) = C(S II) * CA + C(S + 6) * SA 478 CB(15> - C...SPRINT "CYP" ; :OKE 36,43 PRINT C(S + 3); POKE 36,62 PRINT CP(4) H60 PORE 36,30 PRINT "CYR" POKE 36,43 PRINT C(S + 4); POKE 36,62 PRINT C8 (5) 870 POKE...36,62 : PRINT CB(3) 890 POKE 36,30 * PRINT "CLB" * POKE 36,43 * PRINT C(S + 5); : POKE 36,62 * PRINT C8 (6) 988 POKE 36,30 : PRINT "CLP" * POKE 36,43

  6. New development in flying qualities with application to rotary wing aircraft

    NASA Technical Reports Server (NTRS)

    Hoh, R. H.

    1982-01-01

    Some recent considerations and developments in handling quality criteria are reviewed with emphasis on using fixed wing experience gained in developing MIL-F-8785C and the more recent MiL Standard and Handbook. Particular emphasis is placed on the tasks and environmental conditions used to develop the criterion boundaries, SAS failures, and potential fixed wing criteria that are applicable to rotary wing aircraft.

  7. Aircraft Noise and Quality of Life around Frankfurt Airport

    PubMed Central

    Schreckenberg, Dirk; Meis, Markus; Kahl, Cara; Peschel, Christin; Eikmann, Thomas

    2010-01-01

    In a survey of 2,312 residents living near Frankfurt Airport aircraft noise annoyance and disturbances as well as environmental (EQoL) and health-related quality of life (HQoL) were assessed and compared with data on exposure due to aircraft, road traffic, and railway noise. Results indicate higher noise annoyance than predicted from general exposure-response curves. Beside aircraft sound levels source-related attitudes were associated with reactions to aircraft noise. Furthermore, aircraft noise affected EQoL in general, although to a much smaller extent. HQoL was associated with aircraft noise annoyance, noise sensitivity and partly with aircraft noise exposure, in particular in the subgroup of multimorbid residents. The results suggest a recursive relationship between noise and health, yet this cannot be tested in cross-sectional studies. Longitudinal studies would be recommendable to get more insight in the causal paths underlying the noise-health relationship. PMID:20948931

  8. Aircraft noise and quality of life around Frankfurt Airport.

    PubMed

    Schreckenberg, Dirk; Meis, Markus; Kahl, Cara; Peschel, Christin; Eikmann, Thomas

    2010-09-01

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

  9. Handling Qualities Evaluations of Low Complexity Model Reference Adaptive Controllers for Reduced Pitch and Roll Damping Scenarios

    NASA Technical Reports Server (NTRS)

    Hanson, Curt; Schaefer, Jacob; Burken, John J.; Johnson, Marcus; Nguyen, Nhan

    2011-01-01

    National Aeronautics and Space Administration (NASA) researchers have conducted a series of flight experiments designed to study the effects of varying levels of adaptive controller complexity on the performance and handling qualities of an aircraft under various simulated failure or damage conditions. A baseline, nonlinear dynamic inversion controller was augmented with three variations of a model reference adaptive control design. The simplest design consisted of a single adaptive parameter in each of the pitch and roll axes computed using a basic gradient-based update law. A second design was built upon the first by increasing the complexity of the update law. The third and most complex design added an additional adaptive parameter to each axis. Flight tests were conducted using NASA s Full-scale Advanced Systems Testbed, a highly modified F-18 aircraft that contains a research flight control system capable of housing advanced flight controls experiments. Each controller was evaluated against a suite of simulated failures and damage ranging from destabilization of the pitch and roll axes to significant coupling between the axes. Two pilots evaluated the three adaptive controllers as well as the non-adaptive baseline controller in a variety of dynamic maneuvers and precision flying tasks designed to uncover potential deficiencies in the handling qualities of the aircraft, and adverse interactions between the pilot and the adaptive controllers. The work was completed as part of the Integrated Resilient Aircraft Control Project under NASA s Aviation Safety Program.

  10. Handling Qualities of a Capsule Spacecraft During Atmospheric Entry

    NASA Technical Reports Server (NTRS)

    Bilimoria, Karl D.; Mueller, Eric R.

    2010-01-01

    A piloted simulation was conducted to study handling qualities for capsule spacecraft entering the Earth s atmosphere. Eight evaluation pilots, including six pilot astronauts, provided Cooper-Harper ratings, workload ratings, and qualitative comments. The simulation began after descending through the atmospheric entry interface point and continued until the drogue parachutes deployed. There were two categories of piloting tasks, both of which required bank angle control. In one task category, the pilot followed a closed-loop bank angle command computed by the backup guidance system to manage g-loads during entry. In the other task category, the pilot used intuitive rules to determine the desired bank angle independently, based on an open-loop schedule of vertical speed, Mach, and total energy specified at several range-to-target gates along the entry trajectory. Pilots were able to accurately track the bank angle guidance commands and steered the capsule toward the recovery site with essentially the same range error as the benchmark autopilot trajectory albeit with substantially higher propellant usage, and the handling qualities for this task were satisfactory. Another key result was that the complex piloting task of atmospheric entry could be performed satisfactorily, even in the presence of large dispersions, by controlling bank angle to follow a simple open-loop schedule.

  11. Dynamic stability and handling qualities tests on a highly augmented, statically unstable airplane

    NASA Technical Reports Server (NTRS)

    Gera, Joseph; Bosworth, John T.

    1987-01-01

    Initial envelope clearance and subsequent flight testing of a new, fully augmented airplane with an extremely high degree of static instability can place unusual demands on the flight test approach. Previous flight test experience with these kinds of airplanes is very limited or nonexistent. The safe and efficient flight testing may be further complicated by a multiplicity of control effectors that may be present on this class of airplanes. This paper describes some novel flight test and analysis techniques in the flight dynamics and handling qualities area. These techniques were utilized during the initial flight envelope clearance of the X-29A aircraft and were largely responsible for the completion of the flight controls clearance program without any incidents or significant delays.

  12. Orion Handling Qualities During ISS Rendezvous and Docking

    NASA Technical Reports Server (NTRS)

    Hart, Jeremy J.; Stephens, J. P.; Spehar, P.; Bilimoria, K.; Foster, C.; Gonzalex, R.; Sullivan, K.; Jackson, B.; Brazzel, J.; Hart, J.

    2011-01-01

    The Orion spacecraft was designed to rendezvous with multiple vehicles in low earth orbit (LEO) and beyond. To perform the required rendezvous and docking task, Orion must provide enough control authority to perform coarse translational maneuvers while maintaining precision to perform the delicate docking corrections. While Orion has autonomous docking capabilities, it is expected that final approach and docking operations with the International Space Station (ISS) will initially be performed in a manual mode. A series of evaluations was conducted by NASA and Lockheed Martin at the Johnson Space Center to determine the handling qualities (HQ) of the Orion spacecraft during different docking and rendezvous conditions using the Cooper-Harper scale. This paper will address the specifics of the handling qualities methodology, vehicle configuration, scenarios flown, data collection tools, and subject ratings and comments. The initial Orion HQ assessment examined Orion docking to the ISS. This scenario demonstrates the Translational Hand Controller (THC) handling qualities of Orion. During this initial assessment, two different scenarios were evaluated. The first was a nominal docking approach to a stable ISS, with Orion initializing with relative position dispersions and a closing rate of approximately 0.1 ft/sec. The second docking scenario was identical to the first, except the attitude motion of the ISS was modeled to simulate a stress case ( 1 degree deadband per axis and 0.01 deg/sec rate deadband per axis). For both scenarios, subjects started each run on final approach at a docking port-to-port range of 20 ft. Subjects used the THC in pulse mode with cues from the docking camera image, window views, and range and range rate data displayed on the Orion display units. As in the actual design, the attitude of the Orion vehicle was held by the automated flight control system at 0.5 degree deadband per axis. Several error sources were modeled including Reaction

  13. Effects of cockpit lateral stick characteristics on handling qualities and pilot dynamics

    NASA Technical Reports Server (NTRS)

    Mitchell, David G.; Aponso, Bimal L.; Klyde, David H.

    1992-01-01

    This report presents the results of analysis of cockpit lateral control feel-system studies. Variations in feel-system natural frequency, damping, and command sensing reference (force and position) were investigated, in combination with variations in the aircraft response characteristics. The primary data for the report were obtained from a flight investigation conducted with a variable-stability airplane, with additional information taken from other flight experiments and ground-based simulations for both airplanes and helicopters . The study consisted of analysis of handling qualities ratings and extraction of open-loop, pilot-vehicle describing functions from sum-of-sines tracking data, including, for a limited subset of these data, the development of pilot models. The study confirms the findings of other investigators that the effects on pilot opinion of cockpit feel-system dynamics are not equivalent to a comparable level of added time delay, and until a more comprehensive set of criteria are developed, it is recommended that feel-system dynamics be considered a delay-inducing element in the aircraft response. The best correlation with time-delay requirements was found when the feel-system dynamics were included in the delay measurements, regardless of the command reference. This is a radical departure from past approaches.

  14. Piloting Vertical Flight Aircraft: A Conference on Flying Qualities and Human Factors

    NASA Technical Reports Server (NTRS)

    Blanken, Christopher L. (Editor); Whalley, Matthew S. (Editor)

    1993-01-01

    This document contains papers from a specialists' meeting entitled 'Piloting Vertical Flight Aircraft: A Conference on Flying Qualities and Human Factors.' Vertical flight aircraft, including helicopters and a variety of Vertical Takeoff and Landing (VTOL) concepts, place unique requirements on human perception, control, and performance for the conduct of their design missions. The intent of this conference was to examine, for these vehicles, advances in: (1) design of flight control systems for ADS-33C standards; (2) assessment of human factors influences of cockpit displays and operational procedures; (3) development of VTOL design and operational criteria; and (4) development of theoretical methods or models for predicting pilot/vehicle performance and mission suitability. A secondary goal of the conference was to provide an initial venue for enhanced interaction between human factors and handling qualities specialists.

  15. Passenger aircraft cabin air quality: trends, effects, societal costs, proposals.

    PubMed

    Hocking, M B

    2000-08-01

    As aircraft operators have sought to substantially reduce propulsion fuel cost by flying at higher altitudes, the energy cost of providing adequate outside air for ventilation has increased. This has lead to a significant decrease in the amount of outside air provided to the passenger cabin, partly compensated for by recirculation of filtered cabin air. The purpose of this review paper is to assemble the available measured air quality data and some calculated estimates of the air quality for aircraft passenger cabins to highlight the trend of the last 25 years. The influence of filter efficiencies on air quality, and a few medically documented and anecdotal cases of illness transmission aboard aircraft are discussed. Cost information has been collected from the perspective of both the airlines and passengers. Suggestions for air quality improvement are given which should help to result in a net, multistakeholder savings and improved passenger comfort.

  16. Aircraft Transparency Optical Quality: New Methods of Measurement

    DTIC Science & Technology

    1981-02-01

    AFAMRL.TR-1-21 X AIRCRAFT TRANSPARENCY OPTICAL QUALITY: NEW METHODS OF MEASUREMENT LOUIS V. GENCO , O.D., Lt. Colonel HARRY L. TASK, Ph.D. FEBRUARY...aircraft transparency with simple modifications of a positioning fixture ( Genco , 1979). DESIRABLE CHARACTERISTICS The ideal field evaluation unit for...34Windscreen Angular Deviation Measurement Device," U.S. Air Force Invention No. 13647, Patent Pending. Task, Harry L., Louis V. Genco , and Kenneth L. Smith

  17. Flying Quality Analysis of a JAS 39 Gripen Ministick Controller in an F/A-18 Aircraft

    NASA Technical Reports Server (NTRS)

    Carter, John F.; Stoliker, P. C.

    2000-01-01

    NASA Dryden conducted a handling qualities experiment using a small displacement centerstick controller that Saab-Scania developed for the JAS 39 Gripen aircraft. The centerstick, or ministick, was mounted in the rear cockpit of an F/A-18 aircraft. Production support flight control computers (PSFCC) provided a pilot-selectable research control system. The objectives for this experiment included determining whether the mechanical characteristics of the centerstick controller had any significant effect on the handling qualities of the F/A-18, and determining the usefulness of the PSFCCs for this kind of experiment. Five pilots evaluated closed-loop tracking tasks, including echelon and column formation flight and target following. Cooper-Harper ratings and pilot comments were collected for each maneuver. This paper describes the test system, including the PSFCCs, the Gripen centerstick, and the flight test experiment. The paper presents results of longitudinal handling qualities maneuvers, including low order equivalent systems, Neal-Smith, and controls anticipation parameter analyses. The experiment showed that, while the centerstick controller provided a different aircraft feel, few handling qualities deficiencies resulted. It also demonstrated that the PSFCCs were useful for this kind of investigation.

  18. Indoor air quality: recommendations relevant to aircraft passenger cabins.

    PubMed

    Hocking, M B

    1998-07-01

    To evaluate the human component of aircraft cabin air quality the effects of respiration of a resting adult on air quality in an enclosed space are estimated using standard equations. Results are illustrated for different air volumes per person, with zero air exchange, and with various air change rates. Calculated ventilation rates required to achieve a specified air quality for a wide range of conditions based on theory agree to within 2% of the requirements determined using a standard empirical formula. These calculations quantitatively confirm that the air changes per hour per person necessary for ventilation of an enclosed space vary inversely with the volume of the enclosed space. However, they also establish that the ventilation required to achieve a target carbon dioxide concentration in the air of an enclosed space with a resting adult remains the same regardless of the volume of the enclosed space. Concentration equilibria resulting from the interaction of the respiration of a resting adult with various ventilation conditions are compared with the rated air exchange rates of samples of current passenger aircraft, both with and without air recirculation capability. Aircraft cabin carbon dioxide concentrations calculated from the published ventilation ratings are found to be intermediate to these sets of results obtained by actual measurement. These findings are used to arrive at recommendations for aircraft builders and operators to help improve aircraft cabin air quality at minimum cost. Passenger responses are suggested to help improve their comfort and decrease their exposure to disease transmission, particularly on long flights.

  19. Flying qualities and control system characteristics for superaugmented aircraft

    NASA Technical Reports Server (NTRS)

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

    1984-01-01

    Aircraft-alone dynamics and superaugmented control system fundamental regulatory properties including stability and regulatory responses of the basic closed-loop systems; fundamental high and low frequency margins and governing factors; and sensitivity to aircraft and controller parameters are addressed. Alternative FCS mechanizations, and mechanizational side effects are also discussed. An overview of flying qualities considerations encompasses general pilot operations as a controller in unattended, intermittent and trim, and full-attention regulatory or command control; effective vehicle primary and secondary response properties to pilot inputs and disturbances; pilot control architectural possibilities; and comparison of superaugmented and conventional aircraft path responses for different forms of pilot control. Results of a simple experimental investigation into pilot dynamic behavior in attitude control of superaugmented aircraft configurations with high frequency time laps and time delays are presented.

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

    NASA Astrophysics Data System (ADS)

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

    2013-08-01

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

  1. A compilation and analysis of helicopter handling qualities data. Volume 2: Data analysis

    NASA Technical Reports Server (NTRS)

    Heffley, R. K.

    1979-01-01

    A compilation and an analysis of helicopter handling qualities data are presented. Multiloop manual control methods are used to analyze the descriptive data, stability derivatives, and transfer functions for a six degrees of freedom, quasi static model. A compensatory loop structure is applied to coupled longitudinal, lateral and directional equations in such a way that key handling qualities features are examined directly.

  2. Investigation of Control System and Display Variations on Spacecraft Handling Qualities for Docking with Stationary and Rotating Targets

    NASA Technical Reports Server (NTRS)

    Jackson, E. Bruce; Goodrich, Kenneth H.; Bailey, Randall E.; Barnes, James R.; Ragsdale, William A.; Neuhaus, Jason R.

    2010-01-01

    This paper documents the investigation into the manual docking of a preliminary version of the Crew Exploration Vehicle with stationary and rotating targets in Low Earth Orbit. The investigation was conducted at NASA Langley Research Center in the summer of 2008 in a repurposed fixed-base transport aircraft cockpit and involved nine evaluation astronauts and research pilots. The investigation quantified the benefits of a feed-forward reaction control system thruster mixing scheme to reduce translation-into-rotation coupling, despite unmodeled variations in individual thruster force levels and off-axis center of mass locations up to 12 inches. A reduced rate dead-band in the phase-plane attitude controller also showed some promise. Candidate predictive symbology overlaid on a docking ring centerline camera image did not improve handling qualities, but an innovative attitude status indicator symbol was beneficial. The investigation also showed high workload and handling quality problems when manual dockings were performed with a rotating target. These concerns indicate achieving satisfactory handling quality ratings with a vehicle configuration similar to the nominal Crew Exploration Vehicle may require additional automation.

  3. Aircraft

    DTIC Science & Technology

    2002-01-01

    Company, Washington, DC Boeing Commercial Aircraft Division, Seattle, WA and Long Beach, CA Boeing Military Aircraft and Missile Division, St. Louis, MO and... aircraft ; military fixed-wing aircraft ; rotorcraft (helicopters and tiltrotor aircraft ); and aircraft jet engines. Two companies dominate the commercial... aircraft business, Boeing and Airbus. Four companies dominate the military fixed-wing market, Boeing, Lockheed Martin, BAE Systems, and European

  4. Bacteria that Travel: The Quality of Aircraft Water

    PubMed Central

    Handschuh, Harald; Dwyer, Jean O’; Adley, Catherine C.

    2015-01-01

    The travelling population is increasing globally year on year. International tourist arrival figures reached 1087 million in 2013 and 1133 million in 2014; of which 53% and 54% respectively accounted for air transport. The water on board aircraft is sourced from surface or ground water; piped to a central filling point and distributed to each aircraft by water service vehicles at the home base or at the destination airport. The purpose of this study was to ascertain the microbial, chemical (pH; Total and Free chlorine) and physical (temperature) quality of water from two aircraft, long- and short-haul, as well as from the original water source and the water service vehicle. A total of 154 water samples were collected and analysed. Long-haul flights were found to be significantly poorer in terms of microbial quality than short haul flights (p = 0.015). Furthermore, correlation and regression analysis showed that the water service vehicle was a significant source of increased microbial load in aircraft. Microbial diversity was also demonstrated, with 37 bacterial species identified belonging to eight classes: γ-Proteobacteria; β-Proteobacteria; α-Proteobacteria; Bacilli; Actinobacteria; Flavobacteria; Sphingobacteria and Cytophaga; using phenotypic and 16S rDNA sequence-based analysis. We present a novel quantified study of aircraft-related potable water supplies. PMID:26529000

  5. Bacteria that Travel: The Quality of Aircraft Water.

    PubMed

    Handschuh, Harald; O'Dwyer, Jean; Adley, Catherine C

    2015-10-30

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

  6. Handling Qualities Evaluation of the RAAF Museum Fokker Triplane

    DTIC Science & Technology

    1993-06-01

    surface of the axle fairing. 140 mm aft (14 degrees) Pneumatic tyres (with a correct inflation of * 35 psi) are provided. Automotive drum 100 mm laterally...filler caps secure. 10. Tyre condition, inflation and BEFORE ENGINE START wear. Check underneath the brake units for hydraulic fluid 1. Strap-in...although smooth grass runways are aircraft should be landed on the mainwheels, satisfactory (and preferable for tyre wear keeping the tail in the air

  7. Handling Qualities of Large Rotorcraft in Hover and Low Speed

    DTIC Science & Technology

    2015-03-01

    rotor and thus analogous to the moment induced by the rotor flap dynamics in response to pitch rate of the aircraft, such that: = (17) 15...to accelerate forward and the rotors flap aft in response and cause a nose- up pitch . The larger the allowable nacelle rate, the larger the pitch ...due to pitch attitude in terms of the rotor flapping and nacelle dynamics derivatives. The mechanism is that the opposite sense pitching moment induced

  8. Analysis of Handling Qualities Design Criteria for Active Inceptor Force-Feel Characteristics

    NASA Technical Reports Server (NTRS)

    Malpica, Carlos A.; Lusardi, Jeff A.

    2013-01-01

    The force-feel system characteristics of the cyclic inceptors of most helicopters are set based on the characteristics of the mechanical components in the control system (mass, springs, friction dampers, etc.). For these helicopters, the force-feel characteristics typically remain constant over the entire flight envelope, with perhaps a trim release to minimize control forces while maneuvering. With the advent of fly-by-wire control systems and active inceptors in helicopters, the force-feel characteristics are now determined by the closed-loop response of the active inceptor itself as defined by the inertia, force/displacement gradient, damping, breakout force and detent shape configuration parameters in the inceptor control laws. These systems give the flexibility to dynamically prescribe different feel characteristics for different control modes or flight conditions, and the ability to provide tactile cueing to the pilot through the actively controlled side-stick or center-stick cyclic inceptor. For rotorcraft, a few studies have been conducted to assess the effects of cyclic force-feel characteristics on handling qualities in flight. An early study provided valuable insight into the static force-deflection characteristics (force gradient) and the number of axes controlled by the side-stick controller for the U.S. Army's Advanced Digital/Optical Control System (ADOCS) demonstrator aircraft [1]. The first of a series of studies providing insight on the inceptor dynamic force-feel characteristics was conducted on the NASA/Army CH-47B variable-stability helicopter [2]. This work led to a proposed requirement that set boundaries based on the cyclic natural frequency and inertia, with the stipulation of a lower damping ratio limit of 0.3 [3]. A second study was conducted by the Canadian Institute for Aerospace Research using their variable-stability Bell 205A helicopter [4]. This research suggested boundaries for stick dynamics based on natural frequency and damping

  9. Development of Handling Qualities Criteria for Rotorcraft with Externally Slung Loads

    NASA Technical Reports Server (NTRS)

    Hoh, Roger H.; Heffley, Robert K.; Mitchell, David G.

    2006-01-01

    Piloted simulations were performed on the NASA-Ames Vertical Motion Simulator (VMS) to explore handling qualities issues for large cargo helicopters, particularly focusing on external slung load operations. The purpose of this work was based upon the need to include handling qualities criteria for cargo helicopters in an upgrade to the U.S. Army's rotorcraft handling qualities specification, Aeronautical Design Standard-33 (ADS-33E-PRF). From the VMS results, handling qualities criteria were developed fro cargo helicopters carrying external slung loads in the degraded visual environment (DVE). If satisfied, these criteria provide assurance that the handling quality rating (HQR) will be 4 or better for operations in the DVE, and with a load mass ratio of 0.33 or less. For lighter loads, flying qualities were found to be less dependent on the load geometry and therefore the significance of the criteria is less. For heavier loads, meeting the criteria ensures the best possible handling qualities, albeit Level 2 for load mass ratios greater than 0.33.

  10. Flying Qualities Evaluation of a Commuter Aircraft With an Ice Contaminated Tailplane

    NASA Technical Reports Server (NTRS)

    Ranaudo, Richard J.; Ratvasky, Thomas P.; FossVanZante, Judith

    2000-01-01

    During the NASA/FAA (Federal Aviation Administration) Tailplane Icing Program, pilot evaluations of aircraft flying qualities were conducted with various ice shapes attached to the horizontal tailplane of the NASA Twin Otter Icing Research Aircraft. Initially, only NASA pilots conducted these evaluations, assessing the differences in longitudinal flight characteristics between the baseline or clean aircraft, and the aircraft configured with an Ice Contaminated Tailplane (ICT). Longitudinal tests included Constant Airspeed Flap Transitions, Constant Airspeed Thrust Transitions, zero-G Pushovers, Repeat Elevator Doublets, and Simulated Approach and Go-Around tasks. Later in the program, guest pilots from government and industry were invited to fly the NASA Twin Otter configured with a single full-span artificial ice shape attached to the leading edge of the horizontal tailplane. This shape represented ice formed due to a 'Failed Boot' condition, and was generated from tests in the Glenn Icing Research Tunnel on a full-scale tailplane model. Guest pilots performed longitudinal handling tests, similar to those conducted by the NASA pilots, to evaluate the ICT condition. In general, all pilots agreed that longitudinal flying qualities were degraded as flaps were lowered, and further degraded at high thrust settings. Repeat elevator doublets demonstrated reduced pitch damping effects due to ICT, which is a characteristic that results in degraded flying qualities. Pilots identified elevator control force reversals (CFR) in zero-G pushovers at a 20 deg flap setting, a characteristic that fails the FAR 25 no CFR certification requirement. However, when the same pilots used the Cooper-Harper rating scale to perform a simulated approach and go-around task at the 20 deg flap setting, they rated the airplane as having Level I and Level II flying qualities respectively. By comparison, the same task conducted at the 30 deg flap setting, resulted in Level II flying qualities for

  11. The Role of Aircraft Motion in Airborne Gravity Data Quality

    NASA Astrophysics Data System (ADS)

    Childers, V. A.; Damiani, T.; Weil, C.; Preaux, S. A.

    2015-12-01

    Many factors contribute to the quality of airborne gravity data measured with LaCoste and Romberg-type sensors, such as the Micro-g LaCoste Turnkey Airborne Gravity System used by the National Geodetic Survey's GRAV-D (Gravity for the Redefinition of the American Vertical Datum) Project. For example, it is well documented that turbulence is a big factor in the overall noise level of the measurement. Turbulence is best controlled by avoidance; thus flights in the GRAV-D Project are only undertaken when the predicted wind speeds at flight level are ≤ 40 kts. Tail winds are known to be particularly problematic. The GRAV-D survey operates on a number of aircraft in a variety of wind conditions and geographic locations, and an obvious conclusion from our work to date is that the aircraft itself plays an enormous role in the quality of the airborne gravity measurement. We have identified a number of features of the various aircraft which can be determined to play a role: the autopilot, the size and speed of the aircraft, inherent motion characteristics of the airframe, tip tanks and other modifications to the airframe to reduce motion, to name the most important. This study evaluates the motion of a number of the GRAV-D aircraft and looks at the correlation between this motion and the noise characteristics of the gravity data. The GRAV-D Project spans 7 years and 42 surveys, so we have a significant body of data for this evaluation. Throughout the project, the sensor suite has included an inertial measurement unit (IMU), first the Applanix POSAv, and then later the Honeywell MicroIRS IMU as a part of a NovAtel SPAN GPS/IMU system. We compare the noise characteristics of the data with measures of aircraft motion (via pitch, roll, and yaw captured by the IMU) using a variety of statistical tools. It is expected that this comparison will support the conclusion that certain aircraft tend to work well with this type of gravity sensor while others tend to be problematic in

  12. Analysis of the longitudinal handling qualities and pilot-induced-oscillation tendencies of the High-Angle-of-Attack Research Vehicle (HARV)

    NASA Technical Reports Server (NTRS)

    Hess, Ronald A.

    1994-01-01

    The NASA High-Angle-of Attack Research Vehicle (HARV), a modified F-18 aircraft, experienced handling qualities problems in recent flight tests at NASA Dryden Research Center. Foremost in these problems was the tendency of the pilot-aircraft system to exhibit a potentially dangerous phenomenon known as a pilot-induced oscillation (PIO). When they occur, PIO's can severely restrict performance, sharply dimish mission capabilities, and can even result in aircraft loss. A pilot/vehicle analysis was undertaken with the goal of reducing these PIO tendencies and improving the overall vehicle handling qualities with as few changes as possible to the existing feedback/feedforward flight control laws. Utilizing a pair of analytical pilot models developed by the author, a pilot/vehicle analysis of the existing longitudinal flight control system was undertaken. The analysis included prediction of overall handling qualities levels and PIO susceptability. The analysis indicated that improvement in the flight control system was warranted and led to the formulation of a simple control stick command shaping filter. Analysis of the pilot/vehicle system with the shaping filter indicated significant improvements in handling qualities and PIO tendencies could be achieved. A non-real time simulation of the modified control system was undertaken with a realistic, nonlinear model of the current HARV. Special emphasis was placed upon those details of the command filter implementation which could effect safety of flight. The modified system is currently awaiting evaluation in the real-time, pilot-in-the-loop, Dual-Maneuvering-Simulator (DMS) facility at Langley.

  13. A piloted simulator investigation of augmentation systems to improve helicopter nap-of-the-earth handling qualities

    NASA Technical Reports Server (NTRS)

    Chen, R. T. N.; Talbot, P. D.; Gerdes, R. M.; Dugan, D. C.

    1978-01-01

    A piloted simulation study assessed various levels of stability and control augmentation designed to improve the handling qualities of several helicopters in nap-of-the-earth (NOE) flight. Five basic single rotor helicopters - one teetering, two articulated, and two hingeless - which were found to have a variety of major deficiencies in a previous fixed-based simulator study were selected as baseline configurations. The stability and control augmentation systems (SCAS) include simple control augmentation systems (CAS) to decouple pitch and yaw responses due to collective input and to quicken the pitch and roll control responses; SCAS of rate command type designed to optimize the sensitivity and damping and to decouple the pitch-roll due to aircraft angular rate; and attitude command type SCAS. Pilot ratings and commentary are presented as well as performance data related to the task. SCAS control usage and their gain levels associated with specific rotor type are also discussed.

  14. Handling Qualities Evaluation of Pilot Tools for Spacecraft Docking in Earth Orbit

    NASA Technical Reports Server (NTRS)

    Bilimoria, Karl D.; Mueller, Eric; Frost, Chad

    2009-01-01

    A new generation of spacecraft is now under development by NASA to replace the Space Shuttle and return astronauts to the Moon. These spacecraft will have a manual control capability for several mission tasks, and the ease and precision with which pilots can execute these tasks will have an important effect on mission risk and training costs. This paper focuses on the handling qualities of a spacecraft based on dynamics similar to that of the Crew Exploration Vehicle, during the last segment of the docking task with a space station in low Earth orbit. A previous study established that handling qualities for this task degrade significantly as the level of translation-into-rotation coupling increases. The goal of this study is to evaluate the efficacy of various pilot aids designed to mitigate the handling qualities degradation caused by this coupling. Four pilot tools were ev adluaetead:d-band box/indicator, flight-path marker, translation guidance cues, and feed-forward control. Each of these pilot tools improved handling qualities, generally with greater improvements resulting from using these tools in combination. A key result of this study is that feedforward control effectively counteracts coupling effects, providing solid Level 1 handling qualities for the spacecraft configuration evaluated.

  15. Landing flying qualities evaluation criteria for augmented aircraft

    NASA Technical Reports Server (NTRS)

    Radford, R. C.; Smith, R.; Bailey, R.

    1980-01-01

    The criteria evaluated were: Calspan Neal-Smith; Onstott (Northrop Time Domain); McDonnell-Douglas Equivalent System Approach; R. H. Smith Criterion. Each criterion was applied to the same set of longitudinal approach and landing flying qualities data. A revised version of the Neal-Smith criterion which is applicable to the landing task was developed and tested against other landing flying qualities data. Results indicated that both the revised Neal-Smith criterion and the Equivalent System Approach are good discriminators of pitch landing flying qualities; Neal-Smith has particular merit as a design guide, while the Equivalent System Approach is well suited for development of appropriate military specification requirements applicable to highly augmented aircraft.

  16. Aircraft Recirculation Filter for Air-Quality and Incident Assessment

    PubMed Central

    Eckels, Steven J.; Jones, Byron; Mann, Garrett; Mohan, Krishnan R.; Weisel, Clifford P.

    2015-01-01

    The current research examines the possibility of using recirculation filters from aircraft to document the nature of air-quality incidents on aircraft. These filters are highly effective at collecting solid and liquid particulates. Identification of engine oil contaminants arriving through the bleed air system on the filter was chosen as the initial focus. A two-step study was undertaken. First, a compressor/bleed air simulator was developed to simulate an engine oil leak, and samples were analyzed with gas chromatograph-mass spectrometry. These samples provided a concrete link between tricresyl phosphates and a homologous series of synthetic pentaerythritol esters from oil and contaminants found on the sample paper. The second step was to test 184 used aircraft filters with the same gas chromatograph-mass spectrometry system; of that total, 107 were standard filters, and 77 were nonstandard. Four of the standard filters had both markers for oil, with the homologous series synthetic pentaerythritol esters being the less common marker. It was also found that 90% of the filters had some detectable level of tricresyl phosphates. Of the 77 nonstandard filters, 30 had both markers for oil, a significantly higher percent than the standard filters. PMID:25641977

  17. Efficient halal bleeding, animal handling, and welfare: A holistic approach for meat quality.

    PubMed

    Aghwan, Z A; Bello, A U; Abubakar, A A; Imlan, J C; Sazili, A Q

    2016-11-01

    Traditional halal slaughter and other forms of religious slaughter are still an issue of debate. Opposing arguments related to pre-slaughter handling, stress and pain associated with restraint, whether the incision is painful or not, and the onset of unconsciousness have been put forward, but no consensus has been achieved. There is a need to strike a balance between halal bleeding in the light of science and animal welfare. There is a paucity of scientific data with respect to animal welfare, particularly the use of restraining devices, animal handling, and efficient halal bleeding. However, this review found that competent handling of animals, proper use of restraining devices, and the efficient bleeding process that follows halal slaughter maintains meat eating quality. In conclusion, halal bleeding, when carried out in accordance with recommended animal welfare procedures, will not only maintain the quality and wholesomeness of meat but could also potentially reduce suffering and pain. Maintained meat quality increases consumer satisfaction and food safety.

  18. Flight performance using a hyperstereo helmet-mounted display: aircraft handling

    NASA Astrophysics Data System (ADS)

    Jennings, Sion A.; Craig, Gregory L.; Stuart, Geoffrey W.; Kalich, Melvyn E.; Rash, Clarence E.; Harding, Thomas H.

    2009-05-01

    A flight study was conducted to assess the impact of hyperstereopsis on helicopter handling proficiency, workload and pilot acceptance. Three pilots with varying levels of night vision goggle and hyperstereo helmet-mounted display experience participated in the test. The pilots carried out a series of flights consisting of low-level maneuvers over a period of two weeks. Four of the test maneuvers, The turn around the tail, the hard surface landing, the hover height estimation and the tree-line following were analysed in detail. At the end of the testing period, no significant difference was observed in the performance data, between maneuvers performed with the TopOwl helmet and maneuvers performed with the standard night vision goggle. This study addressed only the image intensification display aspects of the TopOwl helmet system. The tests did not assess the added benefits of overlaid symbology or head slaved infrared camera imagery. These capabilities need to be taken into account when assessing the overall usefulness of the TopOwl system. Even so, this test showed that pilots can utilize the image intensification imagery displayed on the TopOwl to perform benign night flying tasks to an equivalent level as pilots using ANVIS. The study should be extended to investigate more dynamic and aggressive low level flying, slope landings and ship deck landings. While there may be concerns regarding the effect of hyperstereopsis on piloting, this initial study suggests that pilots can either adapt or compensate for hyperstereo effects with sufficient exposure and training. Further analysis and testing is required to determine the extent of training required.

  19. Handling qualities criteria for the space shuttle orbiter during the terminal phase of flight

    NASA Technical Reports Server (NTRS)

    Stapleford, R. L.; Klein, R. H.; Hob, R. H.

    1972-01-01

    It was found that large portions of the military handling qualities specification are directly applicable. However a number of additional and substitute criteria are recommended for areas not covered or inadequately covered in the military specification. Supporting pilot/vehicle analyses and simulation experiments were conducted and are described. Results are also presented of analytical and simulator evaluations of three specific interim Orbiter designs which provided a test of the proposed handling qualities criteria. The correlations between the analytical and experimental evaluations were generally excellent.

  20. Evaluation of Flying Qualities and Guidance Displays for an Advanced Tilt-Wing STOL Transport Aircraft in Final Approach and Landing

    NASA Technical Reports Server (NTRS)

    Frost, Chad R.; Franklin, James A.; Hardy, Gordon H.

    2002-01-01

    A piloted simulation was performed on the Vertical Motion Simulator at NASA Ames Research Center to evaluate flying qualities of a tilt-wing Short Take-Off and Landing (STOL) transport aircraft during final approach and landing. The experiment was conducted to assess the design s handling qualities, and to evaluate the use of flightpath-centered guidance for the precision approach and landing tasks required to perform STOL operations in instrument meteorological conditions, turbulence, and wind. Pilots rated the handling qualities to be satisfactory for all operations evaluated except those encountering extreme crosswinds and severe windshear; even in these difficult meteorological conditions, adequate handling qualities were maintained. The advanced flight control laws and guidance displays provided consistent performance and precision landings.

  1. Directional handling qualities requirements for nap of the earth (NOE) tasks

    NASA Technical Reports Server (NTRS)

    Bivens, C. C.

    1985-01-01

    A piloted simulator experiment has been conducted to ascertain the directional axis handling requirements of hover and below 40-kt tasks of a scout/attack helicopter, with attention to such light helicopter configurations as those being considered for the 'LHX' program. Two types of yaw stability and control augmentation system were implemented: one consisted of a washed-out yaw rate feedback and shaped control unit, while the other involved a yaw rate command heading-hold system. Experiment results indicate that rotorcraft configurations with high directional gust sensitivity require greater minimum yaw damping to maintain satisfactory handling qualities in nap of the earth flight. Yaw damping and control response are critical handling qualities parameters in air-to-air target acquisition and tracking.

  2. Flight evaluation of HL-10 lifting body handling qualities at Mach numbers from 0.30 to 1.86

    NASA Technical Reports Server (NTRS)

    Kempel, R. W.; Manke, J. A.

    1974-01-01

    The longitudinal and lateral-directional handling qualities of the HL-10 lifting body vehicle were evaluated in flight at Mach numbers up to 1.86 and altitudes up to approximately 27,450 meters (90,000 feet). In general, the vehicle's handling qualities were considered to be good. Approximately 91 percent of the pilot ratings were 3.5 or better, and 42.4 percent were 2.0. Handling qualities problems were encountered during the first flight due to problems with the control system and vehicle aerodynamics. Modifications of the flight vehicle corrected all deficiencies, and no other significant handling qualities problems were encountered.

  3. Initial Investigation of Reaction Control System Design on Spacecraft Handling Qualities for Earth Orbit Docking

    NASA Technical Reports Server (NTRS)

    Bailey, Randall E.; Jackson, E. Bruce; Goodrich, Kenneth H.; Ragsdale, W. Al; Neuhaus, Jason; Barnes, Jim

    2008-01-01

    A program of research, development, test, and evaluation is planned for the development of Spacecraft Handling Qualities guidelines. In this first experiment, the effects of Reaction Control System design characteristics and rotational control laws were evaluated during simulated proximity operations and docking. Also, the influence of piloting demands resulting from varying closure rates was assessed. The pilot-in-the-loop simulation results showed that significantly different spacecraft handling qualities result from the design of the Reaction Control System. In particular, cross-coupling between translational and rotational motions significantly affected handling qualities as reflected by Cooper-Harper pilot ratings and pilot workload, as reflected by Task-Load Index ratings. This influence is masked but only slightly by the rotational control system mode. While rotational control augmentation using Rate Command Attitude Hold can reduce the workload (principally, physical workload) created by cross-coupling, the handling qualities are not significantly improved. The attitude and rate deadbands of the RCAH introduced significant mental workload and control compensation to evaluate when deadband firings would occur, assess their impact on docking performance, and apply control inputs to mitigate that impact.

  4. Handling Qualities Evaluation, OH-58A Helicopter Incorporating a Ministab 3-Axis Stability Augmentation System

    DTIC Science & Technology

    1975-02-01

    A limited handling qualities evaluation of the OH-58A helicopter incorporating the SFENA 3-axis stability augmentation system called Ministab was...Ministab stability augmentation system was manufactured by the Societe Francaise d’Equipements pour la Navigation Aerienne (SFENA) of France and made

  5. Analysis of Handling Qualities Design Criteria for Active Inceptor Force-Feel Characteristics

    DTIC Science & Technology

    2013-01-01

    a classical regulatory compensatory task. Sub-components for the structural pilot include neuromuscular dynamics ( ), proprioceptive and vestibular...feedback ( and ̇ respectively), and the visual error compensation ( ). Proprioceptive feedback fundamentally accounts for the ability of...inside of the proprioceptive feedback loop. This allows for the modeling approach to be of use in predicting the handling qualities impact of the

  6. Investigation of the effects of bandwidth and time delay on helicopter roll-axis handling qualities

    NASA Technical Reports Server (NTRS)

    Pausder, Heinz-Juergen; Blanken, Chris L.

    1993-01-01

    Several years of cooperative research conducted under the U.S./German Memorandum of Understanding (MOU) in helicopter flight control has recently resulted in a successful handling qualities study. The focus of this cooperative research has been the effects on handling qualities due to time delays in combination with a high bandwidth vehicle. The jointly performed study included the use of U.S. ground-based simulation and German in-flight simulation facilities. The NASA-Ames Vertical Motion Simulator (VMS) was used to develop a high bandwidth slalom tracking task which took into consideration the constraints of the facilities. The VMS was also used to define a range of the test parameters and to perform initial handling qualities evaluations. The flight tests were conducted using DLR's variable-stability BO 105 S3 Advanced Technology Testing Helicopter System (ATTHeS). Configurations included a rate command and an attitude command response system with added time delays up to 160 milliseconds over the baseline and bandwidth values between 1.5 and 4.5 rad/sec. Sixty-six evaluations were performed in about 25 hours of flight time during ten days of testing. The results indicate a need to more tightly constrain the allowable roll axis phase delay for the Level 1 and Level 2 requirements in the U.S. Army's specification for helicopter handling qualities, ADS-33C.

  7. Handling qualities comparison of panoramic night vision goggles and 46-deg. night vision goggles

    NASA Astrophysics Data System (ADS)

    Craig, Gregory; Jennings, Sion; Thorndycraft, David

    2003-09-01

    Night Vision Goggles allow the user to see in extremely low illumination levels but the visual information provided by Night Vision Goggles has a limited field-of-view that diminishes handling-qualities in the night flying environment. Panoramic Night Vision Goggles were designed to correct this problem by providing a 100° horizontal field-of-view which is larger than currently used Night Vision Goggles. However, in the first generation Panoramic Night Vision Goggle, the improved field of view came at the cost of diminished resolution, contrast and central overlap area when compared to conventional Night Vision Goggles. This paper describes an evaluation that was conducted in the variable stability NRC Bell-205 helicopter to examine the influence on system handling qualities of the Panoramic Night Vision Goggles and a 46° field-of-view UK Night Vision Goggle. Five pilots flew the ADS-33D hover, sidestep and pirouette manoeuvres in simulated night conditions with the UK Night Vision Goggle and the Panoramic Night Vision Goggle. Both subjective and objective measures of task performance were obtained. Handling-qualities ratings showed the pirouette was performed better with the Panoramic Night Vision Goggles. This was the only manoeuvre where there was a clear-cut handling qualities improvement when using the Panoramic Night Vision Goggles. Other manoeuvres such as the sidestep and hover did not show definitive handling qualities rating differences between the two Night Vision Goggle types. The flight test results were interpreted in terms of the design trade-offs of the two night vision systems, with regard to the different acuity, binocular overlaps and fields-of-view.

  8. Microphone Handling Noise: Measurements of Perceptual Threshold and Effects on Audio Quality.

    PubMed

    Kendrick, Paul; Jackson, Iain R; Fazenda, Bruno M; Cox, Trevor J; Li, Francis F

    2015-01-01

    A psychoacoustic experiment was carried out to test the effects of microphone handling noise on perceived audio quality. Handling noise is a problem affecting both amateurs using their smartphones and cameras, as well as professionals using separate microphones and digital recorders. The noises used for the tests were measured from a variety of devices, including smartphones, laptops and handheld microphones. The signal features that characterise these noises are analysed and presented. The sounds include various types of transient, impact noises created by tapping or knocking devices, as well as more sustained sounds caused by rubbing. During the perceptual tests, listeners auditioned speech podcasts and were asked to rate the degradation of any unwanted sounds they heard. A representative design test methodology was developed that tried to encourage everyday rather than analytical listening. Signal-to-noise ratio (SNR) of the handling noise events was shown to be the best predictor of quality degradation. Other factors such as noise type or background noise in the listening environment did not significantly affect quality ratings. Podcast, microphone type and reproduction equipment were found to be significant but only to a small extent. A model allowing the prediction of degradation from the SNR is presented. The SNR threshold at which 50% of subjects noticed handling noise was found to be 4.2 ± 0.6 dBA. The results from this work are important for the understanding of our perception of impact sound and resonant noises in recordings, and will inform the future development of an automated predictor of quality for handling noise.

  9. Microphone Handling Noise: Measurements of Perceptual Threshold and Effects on Audio Quality

    PubMed Central

    Kendrick, Paul; Jackson, Iain R.; Fazenda, Bruno M.; Cox, Trevor J.; Li, Francis F.

    2015-01-01

    A psychoacoustic experiment was carried out to test the effects of microphone handling noise on perceived audio quality. Handling noise is a problem affecting both amateurs using their smartphones and cameras, as well as professionals using separate microphones and digital recorders. The noises used for the tests were measured from a variety of devices, including smartphones, laptops and handheld microphones. The signal features that characterise these noises are analysed and presented. The sounds include various types of transient, impact noises created by tapping or knocking devices, as well as more sustained sounds caused by rubbing. During the perceptual tests, listeners auditioned speech podcasts and were asked to rate the degradation of any unwanted sounds they heard. A representative design test methodology was developed that tried to encourage everyday rather than analytical listening. Signal-to-noise ratio (SNR) of the handling noise events was shown to be the best predictor of quality degradation. Other factors such as noise type or background noise in the listening environment did not significantly affect quality ratings. Podcast, microphone type and reproduction equipment were found to be significant but only to a small extent. A model allowing the prediction of degradation from the SNR is presented. The SNR threshold at which 50% of subjects noticed handling noise was found to be 4.2 ± 0.6 dBA. The results from this work are important for the understanding of our perception of impact sound and resonant noises in recordings, and will inform the future development of an automated predictor of quality for handling noise. PMID:26473498

  10. Integrated Application of Active Controls (IAAC) technology to an advanced subsonic transport project-longitudinal handling qualities study of a relaxed-stability airplane

    NASA Technical Reports Server (NTRS)

    1983-01-01

    The results of a piloted simulation of longitudinal handling qualities of an airplane with relaxed static stability are described. This task was performed under the Integrated Application of Active Controls (IAAC) Technology Project within the NASA Energy Efficient Transport Program. A representative medium range transport airplane, the Boeing Model 757, was simulated. Evaluations were made of the unaugmented airplane and of the airplane with an Essential Pitch Augmented Stability (PAS) System and with a Primary PAS System at various center of gravity (cg) conditions. Level 2 pilot ratings were attained with cg locations aft to about 57% mean aerodynamic chord (MAC) or 6% aft of the neutral point for unaugmented landing approach. For Mach = 0.80, unaugmented cruise Level 2 ratings were attained to 47% MAC or 5% forward of the maneuver point. The augmented airplane model provided handling qualities close to or within the Level 1 boundary at all cg locations for both Essential and Primary PAS. Analyses of the test conditions when compared with existing handling qualities criteria based on classical unaugmented airplane characteristics agreed well with the pilot ratings. The unaugmented results are comparable to those reported by both the Douglas Aircraft Company and Lockheed California Company from simulation investigations of transport configurations with roughly similar dimensional and mass characteristics.

  11. The Implications of Handling Qualities in Civil Helicopter Accidents Involving Hover and Low Speed Flight

    NASA Technical Reports Server (NTRS)

    Dugan, Daniel C.; Delamer, Kevin J.

    2005-01-01

    Because of increasing accident rates in Army helicopters in hover and low speed flight, a study was made in 1999 of accidents which could be attributed to inadequate stability augmentation. A study of civil helicopter accidents from 1993-2004 was then undertaken to pursue the issue of poor handling qualities in helicopters which, in almost all cases, had no stability augmentation. The vast majority of the mishaps studied occurred during daylight in visual meteorological condition, reducing the impact of degraded visual environments (DVE) on the results. Based on the Cooper-Harper Rating Scale, the handling qualities of many of the helicopters studied could be described as having from "very objectionable" to "major" deficiencies. These costly deficiencies have resulted in unnecessary loss of life, injury, and high dollar damage. Low cost and lightweight augmentation systems for helicopters have been developed in the past and are still being investigated. They offer the potential for significant reductions in the accident rate.

  12. Effects of dynamic aeroelasticity on handling qualities and pilot rating. [longitudinal control

    NASA Technical Reports Server (NTRS)

    Yen, W. Y.; Swaim, R. L.

    1977-01-01

    Pilot performance parameters, such as pilot ratings, tracking errors, and pilot comments were determined for a longitudinal pitch tracking task using a large, flexible bomber with parametric variations in the undamped natural frequencies of the two lowest frequency symmetric elastic modes. This pitch tracking task was programmed on a fixed base simulator with an electronic attitude-director display of pitch command, pitch angle, and pitch error. Low frequency structural flexibility significantly affects the handling qualities and pilot ratings in the task evaluated.

  13. Ground Based Simulation Evaluation of the Effects of Time Delays and Motion on Rotorcraft Handling Qualities

    DTIC Science & Technology

    1992-01-01

    Inc. C Lometa, CA ADOLPH ATENCIO, JR. DAVID L. KEY Aeroflightdynamics Directorate U.S. Army Aviation Systems Command Ames Research Center Moffett Field...CA JANUARY 1992 - . Final Report Prepared for Aeroflightdynamics Directorate US Army Aviation Systems Command Ames Research Center Moffett Field, CA...Ground-based simulation is an important tool in the assessment of handling qualities of rotorcraft for both research and development. The strengths and

  14. Evaluation of High-Speed Civil Transport Handling Qualities Criteria with Supersonic Flight Data

    NASA Technical Reports Server (NTRS)

    Cox, Timothy H.; Jackson, Dante W.

    1997-01-01

    Most flying qualities criteria have been developed from data in the subsonic flight regime. Unique characteristics of supersonic flight raise questions about whether these criteria successfully extend into the supersonic flight regime. Approximately 25 years ago NASA Dryden Flight Research Center addressed this issue with handling qualities evaluations of the XB-70 and YF-12. Good correlations between some of the classical handling qualities parameters, such as the control anticipation parameter as a function of damping, were discovered. More criteria have been developed since these studies. Some of these more recent criteria are being used in designing the High-Speed Civil Transport (HSCT). A second research study recently addressed this issue through flying qualities evaluations of the SR-71 at Mach 3. The research goal was to extend the high-speed flying qualities experience of large airplanes and to evaluate more recent MIL-STD-1797 criteria against pilot comments and ratings. Emphasis was placed on evaluating the criteria used for designing the HSCT. XB-70 and YF-12 data from the previous research supplemented the SR-71 data. The results indicate that the criteria used in the HSCT design are conservative and should provide good flying qualities for typical high-speed maneuvering. Additional results show correlation between the ratings and comments and criteria for gradual maneuvering with precision control. Correlation is shown between ratings and comments and an extension of the Neal/Smith criterion using normal acceleration instead of pitch rate.

  15. Aircraft

    DOEpatents

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

    1998-09-22

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

  16. Aircraft

    DOEpatents

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

    1998-01-01

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

  17. Handling Qualities of a Large Civil Tiltrotor in Hover using Translational Rate Command

    NASA Technical Reports Server (NTRS)

    Malpica, Carlos A.; Theodore, Colin R.; Lawrence, Ben; Lindsey, James; Blanken, Chris

    2012-01-01

    A Translational Rate Command (TRC) control law has been developed to enable low speed maneuvering of a large civil tiltrotor with minimal pitch changes by means of automatic nacelle angle deflections for longitudinal velocity control. The nacelle actuator bandwidth required to achieve Level 1 handling qualities in hover and the feasibility of additional longitudinal cyclic control to augment low bandwidth nacelle actuation were investigated. A frequency-domain handling qualities criterion characterizing TRC response in terms of bandwidth and phase delay was proposed and validated against a piloted simulation conducted on the NASA-Ames Vertical Motion Simulator. Seven experimental test pilots completed evaluations in the ADS-33E-PRF Hover Mission Task Element (MTE) for a matrix of nacelle actuator bandwidths, equivalent rise times and control response sensitivities, and longitudinal cyclic control allocations. Evaluated against this task, longitudinal phase delay shows the Level 1 boundary is around 0.4 0.5 s. Accordingly, Level 1 handling qualities were achieved either with a nacelle actuator bandwidth greater than 4 rad/s, or by employing longitudinal cyclic control to augment low bandwidth nacelle actuation.

  18. Flight evaluation of the M2-F3 lifting body handling qualities at Mach numbers from 0.30 to 1.61

    NASA Technical Reports Server (NTRS)

    Kempel, R. W.; Dana, W. H.; Sim, A. G.

    1975-01-01

    Percentage distributions of 423 pilot ratings obtained from 27 flights are used to indicate the general level of handling qualities of the M2-F3 lifting body. Percentage distributions are compared on the basis of longitudinal and lateral-directional handling qualities, control system, control system status, and piloting task. Ratings of longitudinal handling qualities at low speed were slightly better than those for transonic and supersonic speed. The ratings of lateral-directional handling qualities were unaffected by speed and configuration. Specific handling qualities problems are discussed in detail, and comparisons are made with pertinent handling qualities criteria.

  19. Design of a digital ride quality augmentation system for commuter aircraft

    NASA Technical Reports Server (NTRS)

    Hammond, T. A.; Amin, S. P.; Paduano, J. D.; Downing, D. R.

    1984-01-01

    Commuter aircraft typically have low wing loadings, and fly at low altitudes, and so they are susceptible to undesirable accelerations caused by random atmospheric turbulence. Larger commercial aircraft typically have higher wing loadings and fly at altitudes where the turbulence level is lower, and so they provide smoother rides. This project was initiated based on the goal of making the ride of the commuter aircraft as smooth as the ride experienced on the major commercial airliners. The objectives of this project were to design a digital, longitudinal mode ride quality augmentation system (RQAS) for a commuter aircraft, and to investigate the effect of selected parameters on those designs.

  20. Microbiological quality and safe handling of enteral diets in a hospital in Minas Gerais, Brazil

    PubMed Central

    Pinto, Raquel Oliveira Medrado; Correia, Eliznara Fernades; Pereira, Keyla Carvalho; Costa, Paulo de Souza; da Silva, Daniele Ferreira

    2015-01-01

    Contamination of enteral diets represents a high risk of compromising the patient's medical condition. To assess the microbiological quality and aseptic conditions in the preparation and administration of handmade and industrialized enteral diets offered in a hospital in the Valley of Jequitinhonha, MG, Brazil, we performed a microbiological analysis of 50 samples of diets and 27 samples of surfaces, utensils, and water used in the preparation of the diets. In addition, we assessed the good handling practices of enteral diets according to the requirements specified by the Brazilian legislation. Both kinds of enteral diets showed contamination by coliforms and Pseudomonas spp. No sample was positive for Staphylococcus aureus and Salmonella spp. On the other hand, Listeria spp. was detected in only one sample of handmade diets. Contamination was significantly higher in the handmade preparations (p < 0.05). Nonconformities were detected with respect to good handling practices, which may compromise the diet safety. The results indicate that the sanitary quality of the enteral diets is unsatisfactory, especially handmade diets. Contamination by Pseudomonas spp. is significant because it is often involved in infection episodes. With regard to aseptic practices, it was observed the need of implementing new procedures for handling enteral diets. PMID:26273278

  1. Effects of changed aircraft noise exposure on experiential qualities of outdoor recreational areas.

    PubMed

    Krog, Norun Hjertager; Engdahl, Bo; Tambs, Kristian

    2010-10-01

    The literature indicates that sound and visual stimuli interact in the impression of landscapes. This paper examines the relationship between annoyance with sound from aircraft and annoyance with other area problems (e.g., careless bicycle riding, crowding, etc.), and how changes in noise exposure influence the perceived overall recreational quality of outdoor recreational areas. A panel study (telephone interviews) conducted before and after the relocation of Norway's main airport in 1998 examined effects of decreased or increased noise exposure in nearby recreational areas (n = 591/455). Sound from aircraft annoyed the largest proportion of recreationists, except near the old airport after the change. The decrease in annoyance with sound from aircraft was accompanied by significant decreases in annoyance with most of the other area problems. Near the new airport annoyance with most factors beside sound from aircraft increased slightly, but not significantly. A relationship between aircraft noise annoyance and perceived overall recreational quality of the areas was found.

  2. Evaluation of XV-15 tilt rotor aircraft for flying qualities research application

    NASA Technical Reports Server (NTRS)

    Radford, R. C.; Schelhorn, A. E.; Siracuse, R. J.; Till, R. D.; Wasserman, R.

    1976-01-01

    The results of a design review study and evaluation of the XV-15 Tilt Rotor Research Aircraft for flying qualities research application are presented. The objectives of the program were to determine the capability of the XV-15 aircraft and the V/STOLAND system as a safe, inflight facility to provide meaningful research data on flying qualities, flight control systems, and information display systems.

  3. Archive data base and handling system for the Orbiter flying qualities experiment program

    NASA Technical Reports Server (NTRS)

    Myers, T. T.; Dimarco, R.; Magdaleno, R. E.; Aponso, B. L.

    1986-01-01

    The OFQ archives data base and handling system assembled as part of the Orbiter Flying Qualities (OFQ) research of the Orbiter Experiments Program (EOX) are described. The purpose of the OFQ archives is to preserve and document shuttle flight data relevant to vehicle dynamics, flight control, and flying qualities in a form that permits maximum use for qualified users. In their complete form, the OFQ archives contain descriptive text (general information about the flight, signal descriptions and units) as well as numerical time history data. Since the shuttle program is so complex, the official data base contains thousands of signals and very complex entries are required to obtain data. The OFQ archives are intended to provide flight phase oriented data subsets with relevant signals which are easily identified for flying qualities research.

  4. Improved Lunar Lander Handling Qualities Through Control Response Type and Display Enhancements

    NASA Technical Reports Server (NTRS)

    Mueller, Eric Richard; Bilimoria, Karl D.; Frost, Chad Ritchie

    2010-01-01

    A piloted simulation that studied the handling qualities for a precision lunar landing task from final approach to touchdown is presented. A vehicle model based on NASA's Altair Lunar Lander was used to explore the design space around the nominal vehicle configuration to determine which combination of factors provides satisfactory pilot-vehicle performance and workload; details of the control and propulsion systems not available for that vehicle were derived from Apollo Lunar Module data. The experiment was conducted on a large motion base simulator. Eight Space Shuttle and Apollo pilot astronauts and three NASA test pilots served as evaluation pilots, providing Cooper-Harper ratings, Task Load Index ratings and qualitative comments. Each pilot flew seven combinations of control response types and three sets of displays, including two varieties of guidance and a nonguided approach. The response types included Rate Command with Attitude Hold, which was used in the original Apollo Moon landings, a Velocity Increment Command response type designed for up-and-away flight, three response types designed specifically for the vertical descent portion of the trajectory, and combinations of these. It was found that Velocity Increment Command significantly improved handling qualities when compared with the baseline Apollo design, receiving predominantly Level 1 ratings. This response type could be flown with or without explicit guidance cues, something that was very difficult with the baseline design, and resulted in approximately equivalent touchdown accuracies and propellant burn as the baseline response type. The response types designed to be used exclusively in the vertical descent portion of the trajectory did not improve handling qualities.

  5. In Flight Evaluation of Active Inceptor Force-Feel Characteristics and Handling Qualities

    DTIC Science & Technology

    2012-05-01

    Concepts Airborne Laboratory ( RASCAL ) JUH- 60A in-flight simulator with an active center stick, and in Germany DLR is utilizing their Active Control...susceptible to bio-feedback interference with the slalom task. It should be noted that when flying the slalom task in the AFDD JUH- 60A RASCAL the...handling qualities has been conducted with a center stick cyclic on the RASCAL JUH- 60A , and initiated with a side stick on the ACT/FHS EC-135. In

  6. Aircraft

    DTIC Science & Technology

    2003-01-01

    national power. But with the recent events such as the war with Iraq, the Severe Acute Respiratory Syndrome (SARS) outbreak, some major carriers... TITLE AND SUBTITLE 2003 Industry Studies: Aircraft 5a. CONTRACT NUMBER 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER 6. AUTHOR(S) 5d. PROJECT NUMBER

  7. Presentation of flight control design and handling quality commonality by separate surface stability augmentation for the family of commuter airplanes

    NASA Technical Reports Server (NTRS)

    Hensley, Douglas; Creighton, Thomas; Haddad, Raphael; Hendrich, Louis; Morgan, Louise; Russell, Mark; Swift, Gerald

    1987-01-01

    The methodology and results for a flight control design and implementation for common handling qualities by Separate Surface Stability Augmentation (SSSA) for the family of commuter airplanes are contained. The open and closed loop dynamics and the design results of augmenting for common handling qualities are presented. The physical and technology requirements are presented for implementing the SSSA system. The conclusion of this report and recommendations for changes or improvement are discussed.

  8. Flying Qualities of Relaxed Static Stability Aircraft. Volume I. Flying Qualities Airworthiness Assessment and Flight Testing of Augmented Aircraft

    DTIC Science & Technology

    1982-09-01

    FOR CURRENT PART 25 AIRCRAFT.... 58 3. MAXIMUM FORCES EXERTED ON AIRCRAFT ,CONTROL STICK (LBS) BY MEN AND WOME No ......,.....o...denotes damped Imaginary Pole in Right oscillatory response) Half Plane (denotes divergent oscillation) I/ x Left Half Plane Right Half Plane stable...unstable) I0 0 ýRealI Pole (denotes rReal Pole in Right Half first obrder ’respornse) Plane (denotes diver~gent- Sfirst order response) . -- ttime -T

  9. An investigation of the effects of pitch-roll (de)coupling on helicopter handling qualities

    NASA Technical Reports Server (NTRS)

    Blanken, C. L.; Pausder, H. J.; Ockier, C. J.

    1995-01-01

    An extensive investigation of the effects of pitch-roll coupling on helicopter handling qualities was performed by the U.S. Army and Deutsche Forschungsanstalt fur Luft- und Raumfahrt (DLR), using a NASA ground-based and a DLR in-flight simulator. Over 90 different coupling configurations were evaluated using a high gain roll-axis tracking task. The results show that although the current ADS-33C coupling criterion discriminates against those types of coupling typical of conventionally controlled helicopters, it is not always suited for the prediction of handling qualities of helicopters with modern control systems. Based on the observation that high frequency inputs during tracking are used to alleviate coupling, a frequency domain pitch-roll coupling criterion that uses the average coupling ratio between the bandwidth and neutral stability frequency is formulated. This criterion provides a more comprehensive coverage with respect to the different types of coupling, shows excellent consistency, and has the additional benefit that compliance testing data are obtained from the bandwidth/phase delay tests, so that no additional flight testing is needed.

  10. Detailed design of a Ride Quality Augmentation System for commuter aircraft

    NASA Technical Reports Server (NTRS)

    Suikat, Reiner; Donaldson, Kent E.; Downing, David R.

    1989-01-01

    The design of a Ride Quality Augmentation System (RQAS) for commuter aircraft is documented. The RQAS is designed for a Cessna 402B, an 8 passenger prop twin representative to this class of aircraft. The purpose of the RQAS is the reduction of vertical and lateral accelerations of the aircraft due to atmospheric turbulence by the application of active control. The detailed design of the hardware (the aircraft modifications, the Ride Quality Instrumentation System (RQIS), and the required computer software) is examined. The aircraft modifications, consisting of the dedicated control surfaces and the hydraulic actuation system, were designed at Cessna Aircraft by Kansas University-Flight Research Laboratory. The instrumentation system, which consist of the sensor package, the flight computer, a Data Acquisition System, and the pilot and test engineer control panels, was designed by NASA-Langley. The overall system design and the design of the software, both for flight control algorithms and ground system checkout are detailed. The system performance is predicted from linear simulation results and from power spectral densities of the aircraft response to a Dryden gust. The results indicate that both accelerations are possible.

  11. Development of EPA aircraft piston engine emission standards. [for air quality

    NASA Technical Reports Server (NTRS)

    Houtman, W.

    1976-01-01

    Piston engine light aircraft are significant sources of carbon monoxide in the vicinity of high activity general aviation airports. Substantial reductions in carbon monoxide were achieved by fuel mixture leaning using improved fuel management systems. The air quality impact of the hydrocarbon and oxides of nitrogen emissions from piston engine light aircraft were insufficient to justify the design constraints being confronted in present control system developments.

  12. A pilot's assessment of helicopter handling-quality factors common to both agility and instrument flying tasks

    NASA Technical Reports Server (NTRS)

    Gerdes, R. M.

    1980-01-01

    A series of simulation and flight investigations were undertaken to evaluate helicopter flying qualities and the effects of control system augmentation for nap-of-the-Earth (NOE) agility and instrument flying tasks. Handling quality factors common to both tasks were identified. Precise attitude control was determined to be a key requirement for successful accomplishment of both tasks. Factors that degraded attitude controllability were improper levels of control sensitivity and damping, and rotor system cross coupling due to helicopter angular rate and collective pitch input. Application of rate command, attitude command, and control input decouple augmentation schemes enhanced attitude control and significantly improved handling qualities for both tasks. The NOE agility and instrument flying handling quality considerations, pilot rating philosophy, and supplemental flight evaluations are also discussed.

  13. Handling Qualities and Stability Derivatives of the X-24B Research Aircraft

    DTIC Science & Technology

    1976-03-01

    unlimited. Distribution authorized to U.S. Gov’t. agencies only; Test and Evaluation; MAR 1976. Other requests shall be referred to Air Force Flight...J Paul wJKirs * PERFORMING ORGANIZATION NAME AND ADDRESS Deputy Oatmander of Operations Air Force Flight Test Center BdwarJU AFB, CA 93523...test pro- accomplished in a joint JffS? between Jhei’ I** X-24B pro^^ waS Laboratory (AFFDL) , the Air PorclpUah^ Af r^Porce Flight

  14. Development of Handling Quality Criteria for Aircraft with Independent Control of Six Degrees of Freedom

    DTIC Science & Technology

    1981-04-01

    DFC input; the input and the resulting 76 𔃻 K L^r^J ^ > SI 60 fe§i T 1 00 "I o Q U O c CO...i ! ^ ^ i i ■ , T : , , 1 -i, : 0 5 Time (sec) Figure 26. Response to Step Input of DFC Control: Wings-Level...1 ’ 1 (jcu) > DFC dB /deg/sec\\ ^ % / (jCü) ’ DFC (deg) -20 •40 -100 ■200 ■300 ,-,„ 1 ■ T ,ll~.-.—

  15. Application of frequency domain handling qualities criteria to the longitudinal landing task

    NASA Technical Reports Server (NTRS)

    Sarrafian, S. K.; Powers, B. G.

    1985-01-01

    Under NASA sponsorship, an in-flight simulation of the longitudinal handling qualities of several configurations for the approach and landing tasks was performed on the USAF/AFWAL Total In-Flight Simulator by the Calspan Corporation. The basic configuration was a generic transport airplane with static instability. The control laws included proportional plus integral gain loops to produce pitch-rate and angle-of-attack feedback loops. The evaluation task was a conventional visual approach to a flared touchdown at a designated spot on the runway with a lateral offset. The general conclusions were that the existing criteria are based on pitch-attitude response and that these characteristics do not adequately discriminate between the good and bad configurations of this study. This paper describes the work that has been done to further develop frequency-based criteria in an effort to provide better correlation with the observed data.

  16. Some lessons learned in three years with ADS-33C. [rotorcraft handling qualities specification

    NASA Technical Reports Server (NTRS)

    Key, David L.; Blanken, Chris L.; Hoh, Roger H.

    1993-01-01

    Three years of using the U.S. Army's rotorcraft handling qualities specification, Aeronautical Design Standard - 33, has shown it to be surprisingly robust. It appears to provide an excellent basis for design and for assessment, however, as the subtleties become more well understood, several areas needing refinement became apparent. Three responses to these needs have been documented in this paper: (1) The yaw-axis attitude quickness for hover target acquisition and tracking can be relaxed slightly. (2) Understanding and application of criteria for degraded visual environments needed elaboration. This and some guidelines for testing to obtain visual cue ratings have been documented. (3) The flight test maneuvers were an innovation that turned out to be very valuable. Their extensive use has made it necessary to tighten definitions and testing guidance. This was accomplished for a good visual environment and is underway for degraded visual environments.

  17. Piloted simulator investigation of helicopter control systems effects on handling qualities during instrument flight

    NASA Technical Reports Server (NTRS)

    Forrest, R. D.; Chen, R. T. N.; Gerdes, R. M.; Alderete, T. S.; Gee, D. R.

    1979-01-01

    An exploratory piloted simulation was conducted to investigate the effects of the characteristics of helicopter flight control systems on instrument flight handling qualities. This joint FAA/NASA study was motivated by the need to improve instrument flight capability. A near-term objective is to assist in updating the airworthiness criteria for helicopter instrument flight. The experiment consisted of variations of single-rotor helicopter types and levels of stability and control augmentation systems (SCAS). These configurations were evaluated during an omnirange approach task under visual and instrument flight conditions. The levels of SCAS design included a simple rate damping system, collective decoupling plus rate damping, and an attitude command system with collective decoupling. A limited evaluation of stick force versus airspeed stability was accomplished. Some problems were experienced with control system mechanization which had a detrimental effect on longitudinal stability. Pilot ratings, pilot commentary, and performance data related to the task are presented.

  18. The development and potential of inverse simulation for the quantitative assessment of helicopter handling qualities

    NASA Technical Reports Server (NTRS)

    Bradley, Roy; Thomson, Douglas G.

    1993-01-01

    In this paper it is proposed that inverse simulation can make a positive contribution to the study of handling qualities. It is shown that mathematical descriptions of the MTEs (Mission Task Elements) defined in ADS-33C may be used to drive an inverse simulation thereby generating, from an appropriate mathematical model, the controls and states of a subject helicopter flying it. By presenting the results of such simulations it is shown that, in the context of inverse simulation, the attitude quickness parameters given in ADS-33C are independent of vehicle configuration. An alternative quickness parameter, associated with the control displacements required to fly the MTE is proposed, and some preliminary results are presented.

  19. Data Quality in web-based HIV/AIDS research: Handling Invalid and Suspicious Data

    PubMed Central

    Bauermeister, Jose; Pingel, Emily; Zimmerman, Marc; Couper, Mick; Carballo-Diéguez, Alex; Strecher, Victor J.

    2011-01-01

    Invalid data may compromise data quality. We examined how decisions taken to handle these data may affect the relationship between Internet use and HIV risk behaviors in a sample of young men who have sex with men (YMSM). We recorded 548 entries during the three-month period, and created 6 analytic groups (i.e., full sample, entries initially tagged as valid, suspicious entries, valid cases mislabeled as suspicious, fraudulent data, and total valid cases) using data quality decisions. We compared these groups on the sample’s composition and their bivariate relationships. Forty-one cases were marked as invalid, affecting the statistical precision of our estimates but not the relationships between variables. Sixty-two additional cases were flagged as suspicious entries and found to contribute to the sample’s diversity and observed relationships. Using our final analytic sample (N = 447; M = 21.48 years old, SD = 1.98), we found that very conservative criteria regarding data exclusion may prevent researchers from observing true associations. We discuss the implications of data quality decisions and its implications for the design of future HIV/AIDS web-surveys. PMID:23180978

  20. Flight evaluation of the effect of winglets on performance and handling qualities of a single-engine general aviation airplane

    NASA Technical Reports Server (NTRS)

    Holmes, B. J.; Vandam, C. P.; Brown, P. W.; Deal, P. L.

    1980-01-01

    A flight evaluation was conducted to determine the effects of winglets on the performance and handling qualities of a light, single-engine general aviation airplane. The performance measurements were made with a pace airplane to provide calibrated airspeeds; uncalibrated panel instruments in the test airplane were used to provide additional quantitative performance data. These tests were conducted with winglets on and off during the same day to measure relative performance effects. Handling qualities were evaluated by means of pilot comments. Winglets increased cruise speed 8 knots (5.6 percent) at 3962 m (13,000 ft) density altitude and 51 percent maximum continuous power setting. Maximum speed at 3962 m was virtually unchanged. Rate of climb increased approximately 6 percent, or 0.25 m/sec (50 ft/min), at 1524 m (5000 ft). Stall speed was virtually unchanged. Handling qualities were favorably affected.

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

    NASA Astrophysics Data System (ADS)

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

    2012-12-01

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

  2. Effects of control laws and relaxed static stability on vertical ride quality of flexible aircraft

    NASA Technical Reports Server (NTRS)

    Roberts, P. A.; Swaim, R. L.; Schmidt, D. K.; Hinsdale, A. J.

    1977-01-01

    State variable techniques are utilized to generate the RMS vertical load factors for the B-52H and B-1 bombers at low level, mission critical, cruise conditions. A ride quality index is proposed to provide meaningful comparisons between different controls or conditions. Ride quality is shown to be relatively invariant under various popular control laws. Handling quality variations are shown to be major contributors to ride quality variations on both vehicles. Relaxed static stability is artificially implemented on the study vehicles to investigate its effects on ride quality. The B-52H ride quality is generally degraded when handling characteristics are automatically restored by a feedback control to the original values from relaxed stability conditions. The B-1 airplane shows little ride quality sensitivity to the same analysis due to the small rigid body contribution to load factors at the flight condition investigated.

  3. Effects of rotor parameter variations on handling qualities of unaugmented helicopters in simulated terrain flight

    NASA Technical Reports Server (NTRS)

    Talbot, P. D.; Dugan, D. D.; Chen, R. T. N.; Gerdes, R. M.

    1980-01-01

    A coordinated analysis and ground simulator experiment was performed to investigate the effects on single rotor helicopter handling qualities of systematic variations in the main rotor hinge restraint, hub hinge offset, pitch-flap coupling, and blade lock number. Teetering rotor, articulated rotor, and hingeless rotor helicopters were evaluated by research pilots in special low level flying tasks involving obstacle avoidance at 60 to 100 knots airspeed. The results of the experiment are in the form of pilot ratings, pilot commentary, and some objective performance measures. Criteria for damping and sensitivity are reexamined when combined with the additional factors of cross coupling due to pitch and roll rates, pitch coupling with collective pitch, and longitudinal static stability. Ratings obtained with and without motion are compared. Acceptable flying qualities were obtained within each rotor type by suitable adjustment of the hub parameters, however, pure teetering rotors were found to lack control power for the tasks. A limit for the coupling parameter L sub q/L sub p of 0.35 is suggested.

  4. Trends in cabin air quality of commercial aircraft: industry and passenger perspectives.

    PubMed

    Hocking, Martin B

    2002-01-01

    The small air space available per person in a fully occupied aircraft passenger cabin accentuates the human bioeffluent factor in the maintenance of air quality. The accumulation of carbon dioxide and other contributions to poor air quality that can occur with inadequate ventilation, even under normal circumstances, is related to the volume of available air space per person and various ventilation rates. This information is compared with established air quality guidelines to make specific recommendations with reference to aircraft passenger cabins under both normal and abnormal operating conditions. The effects of respiration on the air quality of any enclosed space from the respiration of a resting adult are estimated using standard equations. Results are given for different volumes of space per person, for zero air exchange, and for various air change rates. The required ventilation rates estimated in this way compared closely with results calculated using a standard empirical formula. The results confirm that the outside air ventilation required to achieve a target carbon dioxide concentration in the air of an occupied enclosed space remains the same regardless of the volume of that space. The outside air ventilation capability of older and more recent aircraft is then reviewed and compared with the actual measurements of cabin air quality for these periods. The correlation between calculated and measured aircraft cabin carbon dioxide concentrations from other studies was very good. Respiratory benefits and costs of returning to the 30% higher outside air ventilation rates and 8% higher cabin pressures of the 1960s and 1970s are outlined. Consideration is given to the occasional occurrence of certain types of aircraft malfunction that can introduce more serious contaminants to the aircraft cabin. Recommendations and suggestions for aircraft builders and operators are made that will help improve aircraft cabin air quality and the partial pressure of oxygen that

  5. On the Handling Qualities of Flight Vehicles through Variable Flight Conditions.

    DTIC Science & Technology

    1986-01-01

    and Approximations Classical aircraft longitudinal responses are described by a fourth order characteristic equation. In many cases the responses can...3.4.1 Conventional Vehicle Responses Most of the specifications to satisfy aircraft ( longitudinal ) maneuvering requirements are based on short period

  6. Fiber optic (flight quality) sensors for advanced aircraft propulsion

    NASA Technical Reports Server (NTRS)

    Poppel, Gary L.

    1994-01-01

    Development of flight prototype, fiber-optic sensing system components for measuring nine sensed parameters (three temperatures, two speeds, three positions, and one flame) on an F404-400 aircraft engine is described. Details of each sensor's design, functionality, and environmental testing, and the electro-optics architecture for sensor signal conditioning are presented. Eight different optical sensing techniques were utilized. Design, assembly, and environmental testing of an engine-mounted, electro-optics chassis unit (EOU), providing MIL-C-1553 data output, are related. Interconnection cables and connectors between the EOU and the sensors are identified. Results of sensor/cable/circuitry integrated testing, and installation and ground testing of the sensor system on an engine in October 1993 and April 1994 are given, including comparisons with the engine control system's electrical sensors. Lessons learned about the design, fabrication, testing, and integration of the sensor system components are included.

  7. Effects of Changed Aircraft Noise Exposure on Experiential Qualities of Outdoor Recreational Areas

    PubMed Central

    Krog, Norun Hjertager; Engdahl, Bo; Tambs, Kristian

    2010-01-01

    The literature indicates that sound and visual stimuli interact in the impression of landscapes. This paper examines the relationship between annoyance with sound from aircraft and annoyance with other area problems (e.g., careless bicycle riding, crowding, etc.), and how changes in noise exposure influence the perceived overall recreational quality of outdoor recreational areas. A panel study (telephone interviews) conducted before and after the relocation of Norway’s main airport in 1998 examined effects of decreased or increased noise exposure in nearby recreational areas (n = 591/455). Sound from aircraft annoyed the largest proportion of recreationists, except near the old airport after the change. The decrease in annoyance with sound from aircraft was accompanied by significant decreases in annoyance with most of the other area problems. Near the new airport annoyance with most factors beside sound from aircraft increased slightly, but not significantly. A relationship between aircraft noise annoyance and perceived overall recreational quality of the areas was found. PMID:21139858

  8. High-Alpha Handling Qualities Flight Research on the NASA F/A-18 High Alpha Research Vehicle

    NASA Technical Reports Server (NTRS)

    Wichman, Keith D.; Pahle, Joseph W.; Bahm, Catherine; Davidson, John B.; Bacon, Barton J.; Murphy, Patrick C.; Ostroff, Aaron J.; Hoffler, Keith D.

    1996-01-01

    A flight research study of high-angle-of-attack handling qualities has been conducted at the NASA Dryden Flight Research Center using the F/A-18 High Alpha Research Vehicle (HARV). The objectives were to create a high-angle-of-attack handling qualities flight database, develop appropriate research evaluation maneuvers, and evaluate high-angle-of-attack handling qualities guidelines and criteria. Using linear and nonlinear simulations and flight research data, the predictions from each criterion were compared with the pilot ratings and comments. Proposed high-angle-of-attack nonlinear design guidelines and proposed handling qualities criteria and guidelines developed using piloted simulation were considered. Recently formulated time-domain Neal-Smith guidelines were also considered for application to high-angle-of-attack maneuvering. Conventional envelope criteria were evaluated for possible extension to the high-angle-of-attack regime. Additionally, the maneuvers were studied as potential evaluation techniques, including a limited validation of the proposed standard evaluation maneuver set. This paper gives an overview of these research objectives through examples and summarizes result highlights. The maneuver development is described briefly, the criteria evaluation is emphasized with example results given, and a brief discussion of the database form and content is presented.

  9. 76 FR 7096 - Minimum Quality and Handling Standards for Domestic and Imported Peanuts Marketed in the United...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-02-09

    ... Peanuts Marketed in the United States; Section 610 Review AGENCY: Agricultural Marketing Service, USDA...) review of the Minimum Quality and Handling Standards for Domestic and Imported Peanuts Marketed in the... Domestic and Imported Peanuts Marketed in the United States (Standards), as amended (7 CFR part 996),...

  10. 75 FR 22213 - Minimum Quality and Handling Standards for Domestic and Imported Peanuts Marketed in the United...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-04-28

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF AGRICULTURE Agricultural Marketing Service 7 CFR Part 996 Minimum Quality and Handling Standards for Domestic and Imported Peanuts Marketed in the United States; Section 610 Review AGENCY: Agricultural Marketing Service,...

  11. A flight investigation of the stability, control, and handling qualities of an augmented jet flap STOL airplane

    NASA Technical Reports Server (NTRS)

    Vomaske, R. F.; Innis, R. C.; Swan, B. E.; Grossmith, S. W.

    1978-01-01

    The stability, control, and handling qualities of an augmented jet flap STOL airplane are presented. The airplane is an extensively modified de Havilland Buffalo military transport. The modified airplane has two fan-jet engines which provide vectorable thrust and compressed air for the augmentor jet flap and Boundary-Layer Control (BLC). The augmentor and BLC air is cross ducted to minimize asymmetric moments produced when one engine is inoperative. The modifications incorporated in the airplane include a Stability Augmentation System (SAS), a powered elevator, and a powered lateral control system. The test gross weight of the airplane was between 165,000 and 209,000 N (37,000 and 47,000 lb). Stability, control, and handling qualities are presented for the airspeed range of 40 to 180 knots. The lateral-directional handling qualities are considered satisfactory for the normal operating range of 65 to 160 knots airspeed when the SAS is functioning. With the SAS inoperative, poor turn coordination and spiral instability are primary deficiencies contributing to marginal handling qualities in the landing approach. The powered elevator control system enhanced the controllability in pitch, particularly in the landing flare and stall recovery.

  12. HOPE: An On-Line Piloted Handling Qualities Experiment Data Book

    NASA Technical Reports Server (NTRS)

    Jackson, E. B.; Proffitt, Melissa S.

    2010-01-01

    A novel on-line database for capturing most of the information obtained during piloted handling qualities experiments (either flight or simulated) is described. The Hyperlinked Overview of Piloted Evaluations (HOPE) web application is based on an open-source object-oriented Web-based front end (Ruby-on-Rails) that can be used with a variety of back-end relational database engines. The hyperlinked, on-line data book approach allows an easily-traversed way of looking at a variety of collected data, including pilot ratings, pilot information, vehicle and configuration characteristics, test maneuvers, and individual flight test cards and repeat runs. It allows for on-line retrieval of pilot comments, both audio and transcribed, as well as time history data retrieval and video playback. Pilot questionnaires are recorded as are pilot biographies. Simple statistics are calculated for each selected group of pilot ratings, allowing multiple ways to aggregate the data set (by pilot, by task, or by vehicle configuration, for example). Any number of per-run or per-task metrics can be captured in the database. The entire run metrics dataset can be downloaded in comma-separated text for further analysis off-line. It is expected that this tool will be made available upon request

  13. Integrated aerodynamic and control system design of oblique wing aircraft. Ph.D. Thesis

    NASA Technical Reports Server (NTRS)

    Morris, Stephen James

    1990-01-01

    An efficient high speed aircraft design must achieve a high lift to drag ratio at transonic and supersonic speeds. In 1952 Dr. R. T. Jones proved that for any flight Mach number minimum drag at a fixed lift is achieved by an elliptic wing planform with an appropriate oblique sweep angle. Since then, wind tunnel tests and numerical flow models have confirmed that the compressibility drag of oblique wing aircraft is lower than similar symmetrical sweep designs. At oblique sweep angles above thirty degrees the highly asymmetric planform gives rise to aerodynamic and inertia couplings which affect stability and degrade the aircraft's handling qualities. In the case of the NASA-Rockwell Oblique Wing Research Aircraft, attempts to improve the handling qualities by implementing a stability augmentation system have produced unsatisfactory results because of an inherent lack of controllability in the proposed design. The present work focuses on improving the handling qualities of oblique wing aircraft by including aerodynamic configuration parameters as variables in the control system synthesis to provide additional degrees of freedom with which to further decouple the aircraft's response. Handling qualities are measured using a quadratic cost function identical to that considered in optimal control problems, but the controller architecture is not restricted to full state feedback. An optimization procedure is used to simultaneously solve for the aircraft configuration and control gains which maximize a handling qualities measure, while meeting imposed constraints on trim. In some designs wing flexibility is also modeled and reduced order controllers are implemented. Oblique wing aircraft synthesized by this integrated design method show significant improvement in handling qualities when compared to the originally proposed closed loop aircraft. The integrated design synthesis method is then extended to show how handling qualities may be traded for other types of mission

  14. Design of a digital ride quality augmentation system for a commuter aircraft

    NASA Technical Reports Server (NTRS)

    Hammond, T. A.; Downing, D. R.; Amin, S. P.; Paduano, J.

    1984-01-01

    Commuter aircraft with low wing loading that operate at low altitudes are particularly susceptible to unwanted accelerations caused by atmospheric gusts. This paper describes the design and analysis of a longitudinal digital Ride Quality Augmentation System (RQAS). The RQAS designs were conducted for a Cessna 402B aircraft using the flaps and the elevator as the control surfaces. The designs are generated using linear quadratic Gaussian theory and analyzed in both the time and frequency domains. Nominal designs are presented at five flight conditions that cover a total mission. Trade-off studies are conducted to investigate the effect of sample time, computational delay time, servo bandwidth and control power.

  15. Insitu aircraft verification of the quality of satellite cloud winds over oceanic regions

    NASA Technical Reports Server (NTRS)

    Hasler, A. F.; Skillman, W. C.

    1979-01-01

    A five year aircraft experiment to verify the quality of satellite cloud winds over oceans using in situ aircraft inertial navigation system wind measurements is presented. The final results show that satellite measured cumulus cloud motions are very good estimators of the cloud base wind for trade wind and subtropical high regions. The average magnitude of the vector differences between the cloud motion and the cloud base wind is given. For cumulus clouds near frontal regions, the cloud motion agreed best with the mean cloud layer wind. For a very limited sample, cirrus cloud motions also most closely followed the mean wind in the cloud layer.

  16. The effects of lairage time and handling procedure prior to slaughter on stress and meat quality parameters in pigs.

    PubMed

    Dokmanović, M; Velarde, A; Tomović, V; Glamočlija, N; Marković, R; Janjić, J; Baltić, M Ž

    2014-10-01

    Lairage time (short - 8min to 2.7h, n=28 vs. long - 14 to 21.5h, n=72) and pig handling (gentle - no use of stick or electric prod, pig not slipping, falling, nor emitting high-pitched vocalizations vs. rough - where any of these occurred) effects on pig stress and meat quality were measured. Blood lactate and cortisol, plus post-mortem pH (pH60min; pH24h), temperature (T60min), drip loss, sensory and instrumental color and meat quality for the longissimus dorsi, pars lumbalis derived meat were determined. Carcass rigor mortis and skin damages were measured. Lairage time significantly affected blood lactate, carcass rigor mortis, skin damages, drip loss, color and meat quality. Handling procedure influenced blood lactate, pH60min and T60min. Long lairage was more stressful, and was detrimental to carcass quality, but caused better meat quality compared to short lairage. Rough handling was related to higher lactate and lower meat quality.

  17. In situ aircraft verification of the quality of satellite cloud winds over oceanic regions

    NASA Technical Reports Server (NTRS)

    Hasler, A. F.; Skillman, W. C.; Shenk, W. E.; Steranka, J.

    1979-01-01

    A 5-year aircraft experiment to verify the quality of satellite cloud winds over oceans using in situ aircraft Inertial Navigation System wind measurements is presented. Cloud motions measured by satellite and aircraft wind measurements that were coincident in time and space, and the results from the experiment are for undisturbed to moderately disturbed oceanic weather regimes. The results show that satellite measured cumulus cloud motions are good estimators of the cloud-base wind for trade wind and subtropical high regions. The average magnitude of the vector differences between the cloud motion and the cloud-base wind was determined; for cumulus clouds near frontal regions, the cloud motions agreed best with the mean cloud layer wind. For a very limited sample, cirrus cloud motions most closely followed the mean wind in the cloud layer.

  18. Aircraft sound quality for passenger comfort and enhanced product image

    NASA Astrophysics Data System (ADS)

    Wakefield, Gregory H.; Bultemeier, Eric J.; West, Erik; Angerer, James R.; Bhat, Waman V.

    2005-09-01

    Passenger cabin noise requirements for commercial airplanes are being expanded beyond the traditional focus on noise annoyance and speech intelligibility. There is increasing recognition that the passenger response to the cabin soundscape is much more complex; affecting perceptions of product quality, and impacting fatigue and comfort. Tailoring the soundscape for a preferred cabin environment requires the development of metrics that capture a range of passenger responses. In a preliminary exploration of potential metrics, a series of experiments were undertaken to investigate passenger preference for several classes of stationary and transient sounds within the passenger cabin. The design, implementation, and data analysis for these experiments is discussed, along with the application of results to enhance cabin comfort and to convey product quality. Key findings confirm what has been found in sound quality studies in other industries: sound level alone does not fully account for passenger preference.

  19. Close-range photogrammetry for aircraft quality control

    NASA Astrophysics Data System (ADS)

    Schwartz, D. S.

    Close range photogrammetry is applicable to quality assurance inspections, design data acquisition, and test management support tasks, yielding significant cost avoidance and increased productivity. An understanding of mensuration parameters and their related accuracies is fundamental to the successful application of industrial close range photogrammetry. Attention is presently given to these parameters and to the use of computer modelling as an aid to the photogrammetric entrepreneur in industry. Suggested improvements to cameras and film readers for industrial applications are discussed.

  20. Flying qualities design criteria applicable to supersonic cruise aircraft

    NASA Technical Reports Server (NTRS)

    Chalk, C. R.

    1980-01-01

    A comprehensive set of flying qualities design criteria was prepared for use in the supersonic cruise research program. The framework for stating the design criteria is established and design criteria are included which address specific failures, approach to dangerous flight conditions, flight at high angle of attack, longitudinal and lateral directional stability and control, the primary flight control system, and secondary flight controls. Examples are given of lateral directional design criteria limiting lateral accelerations at the cockpit, time to roll through 30 deg of bank, and time delay in the pilot's command path. Flight test data from the Concorde certification program are used to substantiate a number of the proposed design criteria.

  1. 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.

  2. Validation of the Passenger Ride Quality Apparatus (PRQA) for simulation of aircraft motions for ride-quality research

    NASA Technical Reports Server (NTRS)

    Bigler, W. B., II

    1977-01-01

    The NASA passenger ride quality apparatus (PRQA), a ground based motion simulator, was compared to the total in flight simulator (TIFS). Tests were made on PRQA with varying stimuli: motions only; motions and noise; motions, noise, and visual; and motions and visual. Regression equations for the tests were obtained and subsequent t-testing of the slopes indicated that ground based simulator tests produced comfort change rates similar to actual flight data. It was recommended that PRQA be used in the ride quality program for aircraft and that it be validated for other transportation modes.

  3. An Investigation of Large Tilt-Rotor Hover and Low Speed Handling Qualities

    DTIC Science & Technology

    2011-05-01

    power rather suddenly. This, in conjunction with the sudden change in aerodynamic angle of attack naturally caused the aircraft to climb. Pilots...response type control configurations in the Lateral Reposition. Experimental observations suggested that the high bank angles associated with the...runway as soon as the high opposite bank angle was commanded. At this precise moment pilots were also more prone to introducing longitudinal inputs

  4. Handling Qualities of a Large Civil Tiltrotor in Hover using Translational Rate Command

    DTIC Science & Technology

    2012-05-01

    both discuss the possibilities of TRC using Direct Force Control ( DFC ) through forms of thrust vectoring. Reference [16] also presents an analysis of... DFC based response types, taking it to the extent of comparing both acceleration and translational rate response types using both DFC and attitude...based approaches. Reference [13] reports on a fixed-based simulation study based on the AV-8B aircraft, the paper highlights how DFC decouples the

  5. An Inter-comparative Study of the Effects of Aircraft on Surface Air Quality

    NASA Astrophysics Data System (ADS)

    Cameron, M. A.; Jacobson, M. Z.; Barrett, S. R. H.; Bian, H.; Chen, C. C.; Eastham, S. D.; Gettelman, A.; Khodayari, A.; Liang, Q.; Phoenix, D. B.; Selkirk, H. B.; Unger, N.; Wuebbles, D. J.; Yue, X.

    2015-12-01

    This study inter-compares, among five global models, the potential impacts of all commercial aircraft emissions worldwide on surface ozone and PM2.5. The models include climate-response models (CRMs) with interactive meteorology, chemical-transport models (CTMs) with prescribed meteorology, and models that integrate aspects of both. Previously, few studies have addressed the effects of cruise-altitude aircraft emissions on surface air quality, and each has provided a marginally different result. Here, model inputs are substantially harmonized in an effort to achieve a consensus about the state of understanding of impacts of 2006 commercial aviation emissions. Whereas, all models find that aircraft increase near-surface ozone (0.4 to 1.9% globally), perturbations in the Northern Hemisphere are highest in winter, when ambient ozone levels are lower and potentially of not as much concern to human health compared to the higher ozone in the summer months. Changes in surface-level PM2.5 in the CTMs (0.14 to 0.4%) and CRMs (-1.9 to 1.2%) may depend on highly-varying background aerosol fields among models and the inclusion of feedbacks between aircraft emissions and changes in meteorology. The CTMs tend to show an increase in surface PM2.5 primarily over high-traffic regions in the North American mid-latitudes. The CRMs, on the other hand, demonstrate the effects of changing meteorological fields and potential feedbacks on aviation emission impacts, and exhibit large perturbations over regions where natural emissions (e.g., soil dust and sea spray) are abundant. Excluding these emissions in the CRMs results in a smaller-in-magnitude surface change due to aviation. The changes in ozone and PM2.5 found here may be used to estimate ranges in the net impacts of aircraft on human health.

  6. 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.

  7. Effect of pre-slaughter handling, exercise and the presence of a dog on lamb welfare and meat quality.

    PubMed

    Sutherland, M A; Worth, G M; Stuart, A D; Dobbie, P M; Clerens, S

    2016-08-01

    Before slaughter, lambs may experience several stressors such as feed and water deprivation, handling and transport that have the potential to negatively impact welfare and meat quality. The objective of this study was to evaluate the effect of pre-slaughter handling, exercise and the presence of a dog on the behaviour and physiology of lambs and meat quality at slaughter. At 6 months of age, 60 lambs (n=20 lambs/replicate; three replicates) were allocated to one of the two treatment groups (n=30 lambs/treatment): low (LOW) intensive handling or high (HIGH) intensive handling. LOW lambs were moved short distances, quietly and without the use of a dog before transport. HIGH lambs were moved quickly, long distances and with a dog present before transport. Lamb behaviour (standing, lying, rumination and panting) was recorded for 1 h before (post-treatment) and after transport (post-transport), and for 30 min before slaughter (pre-slaughter). Blood samples were collected before (baseline), after transport (post-transport) and at exsanguination (at slaughter) to assess cortisol, lactate and non-esterified fatty acid (NEFA) concentrations. At slaughter, lamb carcases (M. longissimus lumborum) were evaluated for pH levels, drip and cook loss, and tenderness. HIGH lambs spent more time standing (P<0.001) and panting (P<0.001) and less time lying (P<0.001) and ruminating (P<0.001) post-treatment than LOW lambs, but more (P<0.001) time ruminating post-transport. All lambs spent more time standing (P<0.001) and less time lying (P<0.001) and panting (P<0.001) post-transport and pre-slaughter than post-treatment. Cortisol concentrations were greater (P<0.001) in lambs post-transport and at slaughter compared with baseline values. Lactate concentrations were lower (P=0.002) in HIGH than LOW lambs. In addition, NEFA concentrations were higher (P<0.001) post-transport and at slaughter in HIGH compared with LOW lambs. Ultimate pH was higher (P<0.001) in HIGH than LOW lambs and p

  8. Speech intelligibility and speech quality of modified loudspeaker announcements examined in a simulated aircraft cabin.

    PubMed

    Pennig, Sibylle; Quehl, Julia; Wittkowski, Martin

    2014-01-01

    Acoustic modifications of loudspeaker announcements were investigated in a simulated aircraft cabin to improve passengers' speech intelligibility and quality of communication in this specific setting. Four experiments with 278 participants in total were conducted in an acoustic laboratory using a standardised speech test and subjective rating scales. In experiments 1 and 2 the sound pressure level (SPL) of the announcements was varied (ranging from 70 to 85 dB(A)). Experiments 3 and 4 focused on frequency modification (octave bands) of the announcements. All studies used a background noise with the same SPL (74 dB(A)), but recorded at different seat positions in the aircraft cabin (front, rear). The results quantify speech intelligibility improvements with increasing signal-to-noise ratio and amplification of particular octave bands, especially the 2 kHz and the 4 kHz band. Thus, loudspeaker power in an aircraft cabin can be reduced by using appropriate filter settings in the loudspeaker system.

  9. Anticipated Effectiveness of Active Noise Control in Propeller Aircraft Interiors as Determined by Sound Quality Tests

    NASA Technical Reports Server (NTRS)

    Powell, Clemans A.; Sullivan, Brenda M.

    2004-01-01

    Two experiments were conducted, using sound quality engineering practices, to determine the subjective effectiveness of hypothetical active noise control systems in a range of propeller aircraft. The two tests differed by the type of judgments made by the subjects: pair comparisons in the first test and numerical category scaling in the second. Although the results of the two tests were in general agreement that the hypothetical active control measures improved the interior noise environments, the pair comparison method appears to be more sensitive to subtle changes in the characteristics of the sounds which are related to passenger preference.

  10. Control of Next Generation Aircraft and Wind Turbines

    NASA Technical Reports Server (NTRS)

    Frost, Susan

    2010-01-01

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

  11. Historical overview of V/STOL aircraft technology

    NASA Technical Reports Server (NTRS)

    Anderson, S. B.

    1981-01-01

    The requirements for satisfactory characteristics in several key technology areas are discussed and a review is made of various V/STOL aircraft for the purpose of assessing the success or failure of each design in meeting design requirements. Special operating techniques were developed to help circumvent deficiencies. For the most part performance and handling qualities limitations restricted operational evaluations. Flight operations emphasized the need for good STOL performance, good handling qualities, and stability and control augmentation. The majority of aircraft suffered adverse ground effects.

  12. Handling qualities of a wide-body transport airplane utilizing Pitch Active Control Systems (PACS) for relaxed static stability application

    NASA Technical Reports Server (NTRS)

    Grantham, William D.; Person, Lee H., Jr.; Brown, Philip W.; Becker, Lawrence E.; Hunt, George E.; Rising, J. J.; Davis, W. J.; Willey, C. S.; Weaver, W. A.; Cokeley, R.

    1985-01-01

    Piloted simulation studies have been conducted to evaluate the effectiveness of two pitch active control systems (PACS) on the flying qualities of a wide-body transport airplane when operating at negative static margins. These two pitch active control systems consisted of a simple 'near-term' PACS and a more complex 'advanced' PACS. Eight different flight conditions, representing the entire flight envelope, were evaluated with emphasis on the cruise flight conditions. These studies were made utilizing the Langley Visual/Motion Simulator (VMS) which has six degrees of freedom. The simulation tests indicated that (1) the flying qualities of the baseline aircraft (PACS off) for the cruise and other high-speed flight conditions were unacceptable at center-of-gravity positions aft of the neutral static stability point; (2) within the linear static stability flight envelope, the near-term PACS provided acceptable flying qualities for static stabilty margins to -3 percent; and (3) with the advanced PACS operative, the flying qualities were demonstrated to be good (satisfactory to very acceptable) for static stabilty margins to -20 percent.

  13. Lateral-Directional Eigenvector Flying Qualities Guidelines for High Performance Aircraft

    NASA Technical Reports Server (NTRS)

    Davidson, John B.; Andrisani, Dominick, II

    1996-01-01

    This report presents the development of lateral-directional flying qualities guidelines with application to eigenspace (eigenstructure) assignment methods. These guidelines will assist designers in choosing eigenvectors to achieve desired closed-loop flying qualities or performing trade-offs between flying qualities and other important design requirements, such as achieving realizable gain magnitudes or desired system robustness. This has been accomplished by developing relationships between the system's eigenvectors and the roll rate and sideslip transfer functions. Using these relationships, along with constraints imposed by system dynamics, key eigenvector elements are identified and guidelines for choosing values of these elements to yield desirable flying qualities have been developed. Two guidelines are developed - one for low roll-to-sideslip ratio and one for moderate-to-high roll-to-sideslip ratio. These flying qualities guidelines are based upon the Military Standard lateral-directional coupling criteria for high performance aircraft - the roll rate oscillation criteria and the sideslip excursion criteria. Example guidelines are generated for a moderate-to-large, an intermediate, and low value of roll-to-sideslip ratio.

  14. Tensor-based methods for handling missing data in quality-of-life questionnaires.

    PubMed

    Garg, Lalit; Dauwels, Justin; Earnest, Arul; Leong, Khai Pang

    2014-09-01

    A common problem with self-report quality-of-life questionnaires is missing data. Despite enormous care and effort to prevent it, some level of missing data is common and unavoidable. Missing data can have a detrimental impact on the data analysis. In this paper, a novel approach to imputing missing data in quality-of-life questionnaires is proposed, based on matrix and tensor decompositions. In order to illustrate and assess those methods, two datasets are considered: The first dataset contains the responses of 100 patients to a systemic lupus erythematosus-specific quality-of-life questionnaire; the other contains the responses of 43 patients to a rhino-conjunctivitis quality-of-life questionnaire. The two datasets contain almost no missing data, and for testing purposes, data entries are removed at random to have missing completely at random data. Several proportions of missing values are considered, and for each, the imputation error is assessed through k-fold cross validation. We also evaluate different imputation methods for missing at random and missing not at randomdata. The numerical results demonstrate that the proposed tensor factorization-based methods outperform standard methods in terms of root mean square error with at least 4% improvement, while the bias and variance are similar.

  15. Exposure–Response Relationship Between Aircraft Noise and Sleep Quality: A Community-based Cross-sectional Study

    PubMed Central

    Kim, Soo Jeong; Chai, Sang Kug; Lee, Keou Won; Park, Jae-Beom; Min, Kyoung-Bok; Kil, Hyun Gwon; Lee, Chan; Lee, Kyung Jong

    2014-01-01

    Objectives Exposure to aircraft noise has been shown to have adverse health effects, causing annoyance and affecting the health-related quality of life, sleep, and mental states of those exposed to it. This study aimed to determine sleep quality in participants residing near an airfield and to evaluate the relationship between the levels of aircraft noise and sleep quality. Methods Neighboring regions of a military airfield were divided into three groups: a high exposure group, a low exposure group, and a control group. A total of 1082 participants (aged 30–79 years) completed a comprehensive self-administered questionnaire requesting information about demographics, medical history, lifestyle, and the Pittsburgh Sleep Quality Index. Results Of the 1082 participants, 1005 qualified for this study. The prevalence of sleep disturbance was 45.5% in the control group, 71.8% in the low exposure group, and 77.1% in the high exposure group (p for trend < 0.001). After adjusting for potential confounding factors, we determined the exposure–response relationship between the degree of aircraft noise and sleep quality. Of the participants with a normal mental status, the prevalence of sleep disturbance was 2.61-fold higher in the low exposure group and 3.52-fold higher in the high exposure group than in the control group. Conclusion The relationship between aircraft noise and health should be further evaluated through a large-scale follow-up study. PMID:24955321

  16. The effects of pilot stress factors on handling quality assessments during US/German helicopter agility flight tests

    NASA Technical Reports Server (NTRS)

    Pausder, H. J.; Gerdes, R. M.

    1982-01-01

    Flight tests were conducted with two helicopters to study and evaluate the effects of helicopter characteristics and pilot and task demands on performance in nap-of-the-Earth flight. Different, low-level slalom courses were set up and were flown by three pilots with different levels of flight experience. A pilot rating questionnaire was used to obtain redundant information and to gain more insight into factors that influence pilot ratings. The flight test setups and procedures are described, and the pilot ratings are summarized and interpreted in close connection with the analyzed test data. Pilot stress is discussed. The influence of demands on the pilot, of the helicopter characteristics, and of other stress factors are outlined with particular emphasis on how these factors affect handling-qualities assessment.

  17. Evaluation of hygiene practices and microbiological quality of cooked meat products during slicing and handling at retail.

    PubMed

    Pérez-Rodríguez, F; Castro, R; Posada-Izquierdo, G D; Valero, A; Carrasco, E; García-Gimeno, R M; Zurera, G

    2010-10-01

    Cooked meat ready-to-eat products are recognized to be contaminated during slicing which, in the last years, has been associated with several outbreaks. This work aimed to find out possible relation between the hygiene practice taking place at retail point during slicing of cooked meat products in small and medium-sized establishments (SMEs) and large-sized establishments (LEs) and the microbiological quality of sliced cooked meat products. For that, a checklist was drawn up and filled in based on scoring handling practice during slicing in different establishments in Cordoba (Southern Spain). In addition, sliced cooked meats were analyzed for different microbiological indicators and investigated for the presence of Listeria spp. and Listeria monocytogenes. Results indicated that SMEs showed a more deficient handling practices compared to LEs. In spite of these differences, microbiological counts indicated similar microbiological quality in cooked meat samples for both types of establishments. On the other hand, Listeria monocytogenes and Listeria inocua were isolated from 7.35% (5/68) and 8.82% (6/68) of analyzed samples, respectively. Positive samples for Listeria spp. were found in establishments which showed acceptable hygiene levels, though contamination could be associated to the lack of exclusiveness of slicers at retail points. Moreover, Listeria spp presence could not be statistically linked to any microbiological parameters; however, it was observed that seasonality influenced significantly (P<0.05) L. monocytogenes presence, being all samples found during warm season (5/5). As a conclusion, results suggested that more effort should be made to adequately educate handlers in food hygiene practices, focused specially on SMEs.

  18. Aircraft ride quality controller design using new robust root clustering theory for linear uncertain systems

    NASA Technical Reports Server (NTRS)

    Yedavalli, R. K.

    1992-01-01

    The aspect of controller design for improving the ride quality of aircraft in terms of damping ratio and natural frequency specifications on the short period dynamics is addressed. The controller is designed to be robust with respect to uncertainties in the real parameters of the control design model such as uncertainties in the dimensional stability derivatives, imperfections in actuator/sensor locations and possibly variations in flight conditions, etc. The design is based on a new robust root clustering theory developed by the author by extending the nominal root clustering theory of Gutman and Jury to perturbed matrices. The proposed methodology allows to get an explicit relationship between the parameters of the root clustering region and the uncertainty radius of the parameter space. The current literature available for robust stability becomes a special case of this unified theory. The bounds derived on the parameter perturbation for robust root clustering are then used in selecting the robust controller.

  19. Water quality indicators obtainable from aircraft and Landsat images and their use in classifying lakes

    NASA Technical Reports Server (NTRS)

    Scherz, J. P.; Van Domelen, J. F.

    1975-01-01

    Equations describing the interaction of sunlight and skylight with the surface of a lake, particles in the water to the depth where light is extinguished, and lake bottom are presented, and the use of aircraft and Landsat images to derive water quality indicators on the basis of these interactions is discussed. A very clear, deep lake with a backscatter signal similar to that of distilled water is used as a reference standard. The degree of turbidity of other target lakes is determined by comparing their residual radiance with the clear lake standard and with the residual radiance of a lake whose turbidity has been determined from water samples. The relative and absolute strengths of residual radiance are used to determine the type and concentration of suspended material, respectively. Oil slicks are characterized by an increased specular reflectance component, decreased signal from the underlying water, and added backscatter signal from the oil volume.

  20. Effect of epididymis handling conditions on the quality of ram spermatozoa recovered post-mortem.

    PubMed

    Kaabi, M; Paz, P; Alvarez, M; Anel, E; Boixo, J C; Rouissi, H; Herraez, P; Anel, L

    2003-10-15

    Post-mortem spermatozoa recovery is an important technique for obtaining germplasm reserves from genetically valuable animals or endangered species. However, there are many factors that influence the outcome of this technique. We have studied the effect of the interval between animal's death and sperm recovery (0, 24 or 48 h) on the quality and freezability of ram spermatozoa from cauda epididymidis. Storage temperature of epididymis (room temperature or 5 degrees C) was also analysed. Spermatozoa were diluted with Tes-Tris-Fructose solution supplemented with egg yolk (10%) and glycerol (4%), and frozen using a programmable biofreezer (-20 degrees C/min). Pre-freeze and post-thaw sperm samples showed viable spermatozoa up to 48 h after the animal's death, although their quality declined significantly as post-mortem storage time increased. Epididymis sperm stored at 5 degrees C showed better motility and a lower percentage of abnormal forms than epididymis stored at room temperature after 24 and 48 h. The fertilizing ability of cauda epididymis ram spermatozoa obtained at 0 and 24h after the animal's death is similar to that of ejaculated spermatozoa. Therefore, a good protocol for post-mortem semen collection in rams when epididymal spermatozoa cannot be collected immediately, is to preserve the epididymis at 5 degrees C and process the samples in the first 24h after the animal's death.

  1. Helicopter mathematical models and control law development for handling qualities research

    NASA Technical Reports Server (NTRS)

    Chen, Robert T. N.; Lebacqz, J. Victor; Aiken, Edwin W.; Tischler, Mark B.

    1988-01-01

    Progress made in joint NASA/Army research concerning rotorcraft flight-dynamics modeling, design methodologies for rotorcraft flight-control laws, and rotorcraft parameter identification is reviewed. Research into these interactive disciplines is needed to develop the analytical tools necessary to conduct flying qualities investigations using both the ground-based and in-flight simulators, and to permit an efficient means of performing flight test evaluation of rotorcraft flying qualities for specification compliance. The need for the research is particularly acute for rotorcraft because of their mathematical complexity, high order dynamic characteristics, and demanding mission requirements. The research in rotorcraft flight-dynamics modeling is pursued along two general directions: generic nonlinear models and nonlinear models for specific rotorcraft. In addition, linear models are generated that extend their utilization from 1-g flight to high-g maneuvers and expand their frequency range of validity for the design analysis of high-gain flight control systems. A variety of methods ranging from classical frequency-domain approaches to modern time-domain control methodology that are used in the design of rotorcraft flight control laws is reviewed. Also reviewed is a study conducted to investigate the design details associated with high-gain, digital flight control systems for combat rotorcraft. Parameter identification techniques developed for rotorcraft applications are reviewed.

  2. Impact of Aircraft Emissions on Air Quality in the Vicinity of Airports. Volume 4. Nitrogen Dioxide and Hydrocarbons.

    DTIC Science & Technology

    1984-04-01

    Measurement History ........... 3 2.1.2 System Characterization..* ......... o ...................... 14 2.2 Data Analysis and Results...2.2 Field-Program Measurement History .................................. 8 4 2.3 Julian Date/Calendar Date Correspondence...aircraft on air quality have been the subject of a variety of research programs Involvitng both field- measurement programs and computer model

  3. Performance and Handling Qualities - AH-1G Helicopter Equipped with Three Hot Metal/Plume Infrared Suppressors

    DTIC Science & Technology

    1975-04-01

    relative to the aircraft longitudinal axis. The ejector action, created by the engine exhaust as it is accelerated through the replacement nozzle, draws...Lycoming duct is 55 degrees upward relative to the aircraft longitudinal axis. The airflow induced by the ejector is approximately 80 percent of engine...flow. It is estimted that the exhaust gas exits the elbow at approximately 30 degrees relative to the aircraft longitudinal axis. Net increase to the

  4. Establishing quality assurance criteria for serial dilution operations on liquid-handling equipment.

    PubMed

    Popa-Burke, Ioana; Lupotsky, Brian; Boyer, Joseph; Gannon, William; Hughes, Rob; Kadwill, Paul; Lyerly, Donald; Nichols, Jason; Nixon, Elizabeth; Rimmer, Darren; Saiz-Nicolas, Isabel; Sanfiz-Pinto, Beatriz; Holland, Sue

    2009-09-01

    Since the advent of high-throughput screening (HTS) in the early 1990s, parallel multichannel liquid handlers have become a mainstay in every drug discovery setting. Although several peer-reviewed publications have discussed methods and criteria for stamping multiwell copies, there is very little information about establishing a standard operating procedure (SOP) for standard (microliter-level) serial dilutions of compounds used in dose-response experiments. The authors discuss the 4 main criteria any serial dilution process must pass (accuracy, precision, fold dilution, and outliers) and the process for establishing thresholds for all of these values in a compound management or biological screening laboratory. The thresholds need to be both low enough to be acceptable from a biological potency variability perspective and high enough to allow the instruments to pass the quality assurance (QA) analysis on a regular basis. In this article, the authors suggest suitable thresholds arrived at by a variety of methods, including trend analysis of QA data, survey questionnaire from the main stakeholders (screening scientists, chemists), and published criteria for single-shot stamping. A mathematical analysis of the effect of threshold values on estimated XC(50)s was performed to ensure that the variability introduced by the serial dilution step is within acceptable overall variability limits.

  5. ADS-33C related handling qualities research performed using the NRC Bell 205 airborne simulator

    NASA Technical Reports Server (NTRS)

    Morgan, J. Murray; Baillie, Stewart W.

    1993-01-01

    Over 10 years ago a project was initiated by the U.S. Army AVSCOM to update the military helicopter flying qualities specification MIL-8501-A. While not yet complete, the project reached a major milestone in 1989 with the publication of an Airworthiness Design Standard, ADS-33C. The 8501 update project initially set out to identify critical gaps in the requisite data base and then proceeded to fill them using a variety of directed research studies. The magnitude of the task required that it become an international effort: appropriate research studies were conducted in Germany, the UK and Canada as well as in the USA. Canadian participation was supported by the Department of National Defence (DND) through the Chief of Research and Development. Both ground based and in-flight simulation were used to study the defined areas and the Canadian Bell 205-A1 variable stability helicopter was used extensively as one of the primary research tools available for this effort. This paper reviews the involvement of the Flight Research Laboratory of the National Research Council of Canada in the update project, it describes the various experiments conducted on the Airborne Simulator, it notes significant results obtained and describes ongoing research associated with the project.

  6. Automatic control of an aircraft employing outboard horizontal stabilizers

    NASA Astrophysics Data System (ADS)

    Mukherjee, Jason S.

    2000-10-01

    This dissertation concerns the study of radio-operated control of an aircraft using fixed gain and adaptive controllers. The real-time feedback control system is developed to enhance the flying qualities of an experimental model aircraft. The non-conventional flight dynamics of the Outboard Horizontal Stabilizer (OHS) aircraft cause significant differences in the piloting of the aircraft. The control system was added to augment stability as well as to adjust the flight characteristics so that the OHS aircraft handles similar to a conventional aircraft. The control system design process, as applied to recent innovations in aircraft design, is followed. The Outboard Horizontal Stabilizer concept is a non-conventional aircraft, designed to take advantage of the normally wasted energy developed by the wing tip vortices. The research is based on a remotely-controlled OHS aircraft fitted with various sensors and telemetry as part of a real time feedback control system. Fixed gain Linear Quadratic controllers are first applied to the aircraft and result in a dramatic increase in performance at a nominal operating condition. Non-linearities in the OHS aircraft behavior and a wide operating range demanded the development of a variable gain adaptive controller utilizing a parameter estimation scheme to model the plant. The adaptive LQR gain-scheduled controller that emerged gave good performance over a wide flight envelope.

  7. Air Quality in the Mid-Atlantic/Northeast Region: An Aircraft Survey

    NASA Astrophysics Data System (ADS)

    Marufu, L. T.; Doddridge, B.; Taubman, B.; Piety, C.

    2002-12-01

    Parts of the U.S. Mid-Atlantic and Northeast are frequently in violation of the 125 ppbv 1-hr national ambient air quality standard for ozone (O3). The frequency of occurrence and spatial coverage of these violations are expected to increase when/if new standards for fine particulate matter (PM) and ozone averaged over 8-hr come into effect. Online aircraft measurements provide a powerful tool for determining the levels and origins of both primary and secondary pollutants of interest. During the summer of 2002 the University of Maryland at College Park used a twin engine Piper Aztec-F PA-27-250 aircraft to; investigate pollution transport (ozone, haze, and gaseous precursors) over region, state, and class 1 area boundaries; characterize planetary boundary layer (PBL) height, dynamics and development; investigate cross-corridor (transport corridors, metropolitan/ industrial areas) differences in air quality aloft leading to downwind enhancements in pollutants; investigate mesoscale and sub-regional transport influences (e.g. bay and sea breezes, low-level jets, urban island effects) upon near surface air quality and visibility; acquire in situ data for initialization, constraint, and evaluation of ongoing and planned measurement analyses efforts and modeling studies within the region. A total of 54 research flights (192.5 hours), consisting of fixed-position vertical survey spirals and constant altitude transects, were made upwind, near and downwind of selected major cities/industrial areas, transport corridors and class 1 areas in the Northeast, Mid-Atlantic regions. Preliminary results from upwind, near and downwind data show that major cities/industrial areas (Richmond, Washington, Baltimore, Philadelphia, New York and Boston) and transport corridors are net sources of primary and secondary pollutants (gaseous precursors, ozone, and haze). Class 1 areas (Shenandoah national park VA, Lye Brook NY, Mt. Washington in New Hampshire NH and Acadia in ME), on the other

  8. A piloted simulator investigation of static stability and stability/control augmentation effects on helicopter handling qualities for instrument approach

    NASA Technical Reports Server (NTRS)

    Lebacqz, J. V.; Forrest, R. D.

    1980-01-01

    A ground simulator experiment was conducted on the Flight Simulator for Advanced Aircraft at Ames Research Center to investigate the influence of several static stability and stability/control augmentation design parameters on helicopter flying qualities during terminal area operations in instrument conditions. Effects of light turbulence were included. Two levels of static stability in each rotational axis (pitch, roll, yaw) were examined for a hingeless rotor configuration. The variations in pitch and roll were: (1) stable and (2) neutral static stability; in yaw there were two stable levels. Four types of stability/control augmentation were also examined for the lower level of static stability in each axis. This latter investigation covered three helicopter rotor types: hingeless, articulated, and teetering. Four pilots performed a total of 105 evaluations of these parameters for a representative VOR instrument approach task. Pilot rating results indicate the acceptability of neutral static stability longitudinally and laterally and the need for pitch-roll attitude augmentation to achieve a satisfactory system.

  9. Oblique Wing Research Aircraft on ramp

    NASA Technical Reports Server (NTRS)

    1976-01-01

    This 1976 photograph of the Oblique Wing Research Aircraft was taken in front of the NASA Flight Research Center hangar, located at Edwards Air Force Base, California. In the photograph the noseboom, pitot-static probe, and angles-of-attack and sideslip flow vanes(covered-up) are attached to the front of the vehicle. The clear nose dome for the television camera, and the shrouded propellor for the 90 horsepower engine are clearly seen. The Oblique Wing Research Aircraft was a small, remotely piloted, research craft designed and flight tested to look at the aerodynamic characteristics of an oblique wing and the control laws necessary to achieve acceptable handling qualities. NASA Dryden Flight Research Center and the NASA Ames Research Center conducted research with this aircraft in the mid-1970s to investigate the feasibility of flying an oblique wing aircraft.

  10. Impact of Aircraft Emissions on Air Quality in the Vicinity of Airports. Volume I: Recent Airport Measurement Programs, Data Analyses, and Sub-Model Development

    DTIC Science & Technology

    1980-07-01

    by distribu-. ting "hot spot" impacts to other nearby cross wind receptors. A study of the meteorological factors involved in pollutant levels...10.1 aircraft Tier hour, one projects an annual average aircraft impact of about 0.005 ppm (5 ppb). Even allowing an additional factor of two for...jet plume dynamical factors , tends to overpredict the near field air quality impact of aircraft. Studies at commercial air- ports suggest that this

  11. Impacts of aircraft emissions on the air quality near the ground

    NASA Astrophysics Data System (ADS)

    Lee, H.; Olsen, S. C.; Wuebbles, D. J.; Youn, D.

    2013-01-01

    The continuing increase in demand for commercial aviation transport raises questions about the effects of resulting emissions on the environment. The purpose of this study is to investigate, using a global chemistry transport model, to what extent aviation emissions outside the boundary layer influence air quality in the boundary layer. The effects of current levels of aircraft emissions were studied through comparison of multiple simulations allowing for the separated effects of aviation emissions occurring in the low, middle and upper troposphere. We show that emissions near cruise altitudes rather than emissions during landing and take-off are responsible for most of the total odd-nitrogen (NOy), ozone (O3) and aerosol perturbations near the ground with a noticeable seasonal difference. Overall, the perturbations of these species are smaller than 1 ppb even in winter when the perturbations are greater than in summer. Based on the widely used air quality standards and uncertainty of state-of-the-art models, we conclude that aviation-induced perturbations have a negligible effect on air quality even in areas with heavy air traffic. Aviation emissions lead to a less than 1% aerosol enhancement in the boundary layer due to a slight increase in ammonium nitrate (NH4NO3) during cold seasons and a statistically insignificant aerosol perturbation in summer. In addition, statistical analysis using probability density functions, Hellinger distance, and p-value indicate that aviation emissions outside the boundary layer do not affect the occurrence of extremely high aerosol concentrations in the boundary layer. An additional sensitivity simulation assuming the doubling of surface ammonia emissions demonstrates that the aviation induced aerosol increase near the ground is highly dependent on background ammonia concentrations whose current range of uncertainty is large.

  12. Impacts of aircraft emissions on the air quality near the ground

    NASA Astrophysics Data System (ADS)

    Lee, H.; Olsen, S. C.; Wuebbles, D. J.; Youn, D.

    2013-06-01

    The continuing increase in demand for commercial aviation transport raises questions about the effects of resulting emissions on the environment. The purpose of this study is to investigate, using a global chemistry transport model, to what extent aviation emissions outside the boundary layer influence air quality in the boundary layer. The large-scale effects of current levels of aircraft emissions were studied through comparison of multiple simulations allowing for the separated effects of aviation emissions occurring in the low, middle and upper troposphere. We show that emissions near cruise altitudes (9-11 km in altitude) rather than emissions during landing and take-off are responsible for most of the total odd-nitrogen (NOy), ozone (O3) and aerosol perturbations near the ground with a noticeable seasonal difference. Overall, the perturbations of these species are smaller than 1 ppb even in winter when the perturbations are greater than in summer. Based on the widely used air quality standards and uncertainty of state-of-the-art models, we conclude that aviation-induced perturbations have a negligible effect on air quality even in areas with heavy air traffic. Aviation emissions lead to a less than 1% aerosol enhancement in the boundary layer due to a slight increase in ammonium nitrate (NH4NO3) during cold seasons and a statistically insignificant aerosol perturbation in summer. In addition, statistical analysis using probability density functions, Hellinger distance, and p value indicate that aviation emissions outside the boundary layer do not affect the occurrence of extremely high aerosol concentrations in the boundary layer. An additional sensitivity simulation assuming the doubling of surface ammonia emissions demonstrates that the aviation induced aerosol increase near the ground is highly dependent on background ammonia concentrations whose current range of uncertainty is large.

  13. Application of active controls technology to aircraft bide smoothing systems

    NASA Technical Reports Server (NTRS)

    Lapins, M.; Jacobson, I. D.

    1975-01-01

    A critical review of past efforts in the design and testing of ride smoothing and gust alleviation systems is presented. Design trade offs involving sensor types, choice of feedback loops, human comfort, and aircraft handling-qualities criteria are discussed. Synthesis of a system designed to employ direct-lift and side-force producing surfaces is reported. Two STOL aircraft and an executive transport are considered. Theoretically predicted system performance is compared with hybrid simulation and flight test data. Pilot opinion rating, pilot workload, and passenger comfort rating data for the basic and augmented aircraft are included.

  14. Application of Active Controls Technology to Aircraft Ride Smoothing Systems

    NASA Technical Reports Server (NTRS)

    Lapins, Maris; Jacobson, Ira D.

    1975-01-01

    A critical review of past efforts in the design and testing of ride smoothing and gust alleviation systems is presented. Design trade-offs involving sensor types, choice of feedback loops, human comfort and aircraft handling-qualities criteria are discussed. Synthesis of a system designed to employ direct-lift and side-force producing surfaces is reported. Two STOL-class aircraft and an executive transport are considered. Theoretically-predicted system performance is compared with hybrid simulation and flight test data. Pilot opinion rating, pilot workload, and passenger comfort rating data for the basic and augmented aircraft are included.

  15. A Risk Management Architecture for Emergency Integrated Aircraft Control

    NASA Technical Reports Server (NTRS)

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

    2011-01-01

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

  16. An experimental evaluation of the Sternberg task as a workload metric for helicopter Flight Handling Qualities (FHQ) research

    NASA Technical Reports Server (NTRS)

    Hemingway, J. C.

    1984-01-01

    The objective was to determine whether the Sternberg item-recognition task, employed as a secondary task measure of spare mental capacity for flight handling qualities (FHQ) simulation research, could help to differentiate between different flight-control conditions. FHQ evaluations were conducted on the Vertical Motion Simulator at Ames Research Center to investigate different primary flight-control configurations, and selected stability and control augmentation levels for helicopters engaged in low-level flight regimes. The Sternberg task was superimposed upon the primary flight-control task in a balanced experimental design. The results of parametric statistical analysis of Sternberg secondary task data failed to support the continued use of this task as a measure of pilot workload. In addition to the secondary task, subjects provided Cooper-Harper pilot ratings (CHPR) and responded to workload questionnaire. The CHPR data also failed to provide reliable statistical discrimination between FHQ treatment conditions; some insight into the behavior of the secondary task was gained from the workload questionnaire data.

  17. Pre-slaughter sound levels and pre-slaughter handling from loading at the farm till slaughter influence pork quality.

    PubMed

    Vermeulen, L; Van de Perre, V; Permentier, L; De Bie, S; Verbeke, G; Geers, R

    2016-06-01

    This study investigates the relationship between sound levels, pre-slaughter handling during loading and pork quality. Pre-slaughter variables were investigated from loading till slaughter. A total of 3213 pigs were measured 30 min post-mortem for pH(30LT) (M. Longissimus thoracis). First, a sound level model for the risk to develop PSE meat was established. The difference in maximum and mean sound level during loading, mean sound level during lairage and mean sound level prior to stunning remained significant within the model. This indicated that sound levels during loading had a significant added value to former sound models. Moreover, this study completed the global classification checklist (Vermeulen et al., 2015a) by developing a linear mixed model for pH(30LT) and PSE prevalence, with the difference in maximum and mean sound level measured during loading, the feed withdrawal period and the difference in temperature during loading and lairage. Hence, this study provided new insights over previous research where loading procedures were not included.

  18. A Limited Handling Qualities Evaluation of an In-Flight Simulation of the 2003 Wright Flyer, HAVE WRIGHT

    DTIC Science & Technology

    2001-06-01

    OFF OFF ON 2 ON OFF ON 3 ON ON ON 4 OFF OFF OFF Notes: 1. SAS = Stability Augmentation System . 2. WRI = Warp-Rudder Interconnect. 3. On the VVSLIS...The VVSLIS aircraft configuration was landing gear down and flaps 20% for all flight tests. The pitch Stability Augmentation System (SAS) consisted...aircraft with and without various levels of augmentation including a pitch Stability Augmentation System (SAS), a roll SAS, and a Warp-Rudder

  19. Lightning protection of aircraft

    NASA Technical Reports Server (NTRS)

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

    1977-01-01

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

  20. Preliminary control law and hardware designs for a ride quality augmentation system for commuter aircraft. Phase 2

    NASA Technical Reports Server (NTRS)

    Davis, D. J.; Linse, D. J.; Suikat, R.; Entz, D. P.

    1986-01-01

    The continued investigation of the design of Ride Quality Augmentation Systems (RQAS) for commuter aircraft is described. The purpose of these RQAS is the reduction of the vertical and lateral acceleration response of the aircraft due to atmospheric turbulence by the application of active control. The current investigations include the refinement of the sample data feedback control laws based on the control-rate-weighting and output-weighting optimal control design techniqes. These control designs were evaluated using aircraft time simulations driven by Dryden spectra turbulence. Fixed gain controllers were tested throughout the aircrft operating envelope. The preliminary design of the hardware modifications necessary to implement and test the RQAS on a commuter aircraft is included. These include a separate surface elevator and the flap modifications to provide both direct lift and roll control. A preliminary failure mode investigation was made for the proposed configuration. The results indicate that vertical acceleration reductions of 45% and lateral reductions of more than 50% are possible. A fixed gain controller appears to be feasible with only minor response degradation.

  1. V/STOL tilt rotor aircraft study mathematical model for a real time simulation of a tilt rotor aircraft (Boeing Vertol Model 222), volume 8

    NASA Technical Reports Server (NTRS)

    Rosenstein, H.; Mcveigh, M. A.; Mollenkof, P. A.

    1973-01-01

    A mathematical model for a real time simulation of a tilt rotor aircraft was developed. The mathematical model is used for evaluating aircraft performance and handling qualities. The model is based on an eleven degree of freedom total force representation. The rotor is treated as a point source of forces and moments with appropriate response time lags and actuator dynamics. The aerodynamics of the wing, tail, rotors, landing gear, and fuselage are included.

  2. Application of ride quality technology to predict ride satisfaction for commuter-type aircraft

    NASA Technical Reports Server (NTRS)

    Jacobson, I. D.; Kuhlthau, A. R.; Richards, L. G.

    1975-01-01

    A method was developed to predict passenger satisfaction with the ride environment of a transportation vehicle. This method, a general approach, was applied to a commuter-type aircraft for illustrative purposes. The effect of terrain, altitude and seat location were examined. The method predicts the variation in passengers satisfied for any set of flight conditions. In addition several noncommuter aircraft were analyzed for comparison and other uses of the model described. The method has advantages for design, evaluation, and operating decisions.

  3. Ride Quality Design Criteria for Aircraft with Active Mode Control Systems

    DTIC Science & Technology

    1972-10-01

    comfort or effectiveness level. Nearly all modern aircraft have a stability augmentation system . These systems are designed primarily for rigid body... Augmentation System Design for Low Altitude, High Speed Flexible Aircraft, AFFDL-rR-67-49, February 1968. 4. C. B. Notess, A Triangle-Flexible Airplanes...Structural Design Criteria by Statistical Methods, AFFDL-TR-67-107, June 1968. 3. J. H. Wykes, et al, A Gust Alleviatlon and Structural Dynamic Stability

  4. The Air Quality and Economic Impact of Atmospheric Lead from General Aviation Aircraft in the United States

    NASA Astrophysics Data System (ADS)

    Wolfe, P. J.; Selin, N. E.; Barrett, S. R. H.

    2015-12-01

    While leaded fuels for automobiles were phased-out of use in the United States by 1996, lead (Pb) continues to be used as an anti-knock additive for piston-driven aircraft. We model the annual concentration of atmospheric lead attributable to piston driven aircraft emissions in the continental United States using the Community Multi-scale Air Quality (CMAQ) model. Using aircraft emissions inventories for 2008, we then calculate annual economic damages from lead as lifetime employment losses for a one-year cohort exposed to elevated atmospheric lead concentrations using a range of concentration response functions from literature. Mean and median estimates of annual damages attributable to lifetime lost earnings are 1.06 and 0.60 billion respectively. Economy-wide impacts of IQ-deficits on productivity and labor increase expected damages by 54%. Damages are sensitive to background lead concentrations; as emissions decrease from other sources, the damages attributable to aviation are expected to increase holding aviation emissions constant. The monetary impact of General Aviation lead emissions on the environment is the same order of magnitude as noise, climate change, and air quality degradation from all commercial operations.

  5. A helicopter handling-qualities study of the effects of engine response characteristics, height-control dynamics, and excess power on nap-of-the-Earth operations

    NASA Technical Reports Server (NTRS)

    Corliss, L. D.

    1982-01-01

    The helicopter configuration with an rpm-governed gas-turbine engine was examined. A wide range of engine response time, vehicle damping and sensitivity, and excess power levels was studied. The data are compared with the existing handling-qualities specifications, MIL-F-83300 and AGARD 577, and in general show a need for higher minimums when performing such NOE maneuvers as a dolphin and bob-up task.

  6. Aircraft versus spacecraft for remote monitoring of water quality in U.S. coastal zones

    NASA Technical Reports Server (NTRS)

    Darnell, W. L.

    1977-01-01

    To provide guidance for conducting future water monitoring missions over U.S. coasts, aircraft and spacecraft approaches were defined and quantitatively compared. Sensors, aircraft and spacecraft were selected from current or developmental types for the hardware concepts and monitoring was assumed to begin in 1981-1983. Comparative data are presented on capabilities and costs to monitor both recognized pollution sites and broad shelf areas. For these mission requirements, a large fleet of light aircraft provided better coverage and at lower costs generally than one spacecraft, assuming a single, multi-spectral sensor on each platform. This result could change, however, should additional useful sensors with low cost penalties be found for the spacecraft.

  7. Quality and safety issues highlighted by patients in the handling of laboratory test results by general practices–a qualitative study

    PubMed Central

    2014-01-01

    Background In general practice internationally, many care teams handle large numbers of laboratory test results relating to patients in their care. Related research about safety issues is limited with most of the focus on this workload from secondary care and in North American settings. Little has been published in relation to primary health care in the UK and wider Europe. This study aimed to explore experiences and perceptions of patients with regards to the handling of test results by general practices. Methods A qualitative research approach was used with patients. The setting was west of Scotland general practices from one National Health Service territorial board area. Patients were purposively sampled from practice held lists of patients who received a number of laboratory tests because of chronic medical problems or surveillance of high risk medicines. Focus groups were held and were audio-recorded. Tapes were transcribed and subjected to qualitative analysis. Transcripts were coded and codes merged into themes by two of the researchers. Results 19 participants from four medical practices took part in four focus groups. The main themes identified were: 1. Patients lacked awareness of the results handling process in their practice. 2. Patients usually did not contact their practice for test results, unless they considered themselves to be ill. 3. Patients were concerned about the appropriateness of administrators being involved in results handling. 4. Patients were concerned about breaches of confidentiality when administrators were involved in results handling. 5. Patients valued the use of dedicated results handling staff. 6. Patients welcomed the use of technology to alert them to results being available, and valued the ability to choose how this happened. Conclusions The study confirms the quality and safety of care problems associated with results handling systems and adds to our knowledge of the issues that impact in these areas. Practices need to be

  8. Multi-elemental analysis of jet engine lubricating oils and hydraulic fluids and their implication in aircraft air quality incidents.

    PubMed

    van Netten, C

    1999-05-07

    The flight crews of aircraft often report symptoms including dizziness, nausea, disorientation, blurred vision and tingling in legs and arms. Many of these incidents have been traced to contamination of cabin air with lubricating oil, as well as hydraulic fluid, constituents. Considering that these air contaminants are often subjected to temperatures in excess of 500 degrees C, a large number of different exposures can be expected. Although the reported symptoms are most consistent with exposures to volatile organic compounds, carbon monoxide, and the organophosphate constituents in these oils and fluids, the involvement of these agents has not been clearly demonstrated. Possible exposure to toxic elements, such as lead, mercury, thallium and others, have not been ruled out. In order to assess the potential of exposure to toxic elements a multi-elemental analysis was done on two hydraulic fluids and three lubricating oils which have been implicated in a number of air quality incidents. A secondary objective was to establish if the multi-elemental concentrations of the fluids tested are different enough to allow such an analysis to be used as a possible method of identifying the source of exposure that might have been present during aircraft air quality incidents. No significant concentrations of toxic elements were identified in any of the oils or hydraulic fluids. The elemental compositions of the samples were different enough to be used for identification purposes and the measurement of only three elements was able to achieve this. Whether these findings have an application, in aircraft air quality incident investigations, needs to be established with further studies.

  9. Fuel Consumption Modeling of a Transport Category Aircraft Using Flight Operations Quality Assurance Data: A Literature Review

    NASA Technical Reports Server (NTRS)

    Stolzer, Alan J.

    2002-01-01

    Fuel is a major cost expense for air carriers. A typical airline spends 10% of its operating budget on the purchase of jet fuel, which even exceeds its expenditures on aircraft acquisitions. Thus, it is imperative that fuel consumption be managed as wisely as possible. The implementation of Flight Operations Quality Assurance (FOQA) programs at airlines may be able to assist in this management effort. The purpose of the study is to examine the literature regarding fuel consumption by air carriers, the literature related to air carrier fuel conservation efforts, and the literature related to the appropriate statistical methodologies to analyze the FOQA-derived data.

  10. Droplet Handling

    NASA Astrophysics Data System (ADS)

    Torii, Toru

    When quantitative analysis or quantitative chemical synthesis is performed using a micrototal analysis system (microTAS), the technologies for precise metering, transporting, and mixing of droplets are required. In this chapter, several technologies for the handling of droplets are described. For metering, dispensing and transporting of droplets, pneumatic and electrokinetic forces are used. Separation of cells and particles is also performed by electrical operation. Other handling technique, such as ultrasonic or centrifugal force applications, are also reviewed. Robotic synthesis devices or high throughput screening devices are promising applications for these technologies.

  11. Droplet handling.

    PubMed

    Torii, Toru

    2010-01-01

    When quantitative analysis or quantitative chemical synthesis is performed using a micrototal analysis system (microTAS), the technologies for precise metering, transporting, and mixing of droplets are required. In this chapter, several technologies for the handling of droplets are described. For metering, dispensing and transporting of droplets, pneumatic and electrokinetic forces are used. Separation of cells and particles is also performed by electrical operation. Other handling technique, such as ultrasonic or centrifugal force applications, are also reviewed. Robotic synthesis devices or high throughput screening devices are promising applications for these technologies.

  12. Correlation of ERTS-1 and aircraft optical data with water quality parameters of Charlotte Amalie Harbor, St. Thomas, Virgin Islands

    NASA Technical Reports Server (NTRS)

    Coulbourn, W. C.; Egan, W. G. (Principal Investigator)

    1973-01-01

    The author has identified the following significant results. Attempts to correlate optical aircraft remote sensing of water quality with the optical data from the ERTS-1 satellite using calibrated imagery of Charlotte Amalie harbor, St. Thomas, Virgin Islands are reported. The harbor at Charlotte Amalie has a concentration of a number of factors affecting water quality: untreated sewage, land runoff, and sediment from navigation and dredging operations. Calibration procedures have been originated and applied to ERTS-1 and I2S camera imagery. The results indicate that the ERTS-1 and I2S imagery are correlated with optical in situ measurements of the harbor water. The aircraft green photographic and ERTS-1 MSS-4 bands have been found most suitable for monitoring the scattered light levels under the conditions of the investigation. The chemical parameters of the harbor water were found to be correlated to the optical properties for two stations investigated in detail. The biological properties of the harbor water (chlorophyll and carotenoids), correlate inversely with the optical data near the pollution sources compared to further away. Calibration procedures developed in this investigation were essential to the interpretation of the photographic and ERTS-1 photometric responses.

  13. Boundaries of ERTS and aircraft data within which useful water quality information can be obtained

    NASA Technical Reports Server (NTRS)

    Egan, W. G.

    1974-01-01

    Calibration procedures have been devised and applied to ERTS-1, multispectral, true color, and false color imagery. The results indicate that the ERTS and multispectral imagery are correlated with optical in situ measurements of the harbor water. Correlation is extended to true and false color imagery through in situ optical measurements of the harbor water. The best photometric accuracy is achieved with multispectral aerial imagery and the use of bulk MSS tape. The aircraft green photographic and ERTS-1 MSS-4 bands have been found most suitable for monitoring the scattered light levels under the conditions of this investigation. The application of satellite or aircraft for optical remote sensing depends upon the physical scale and frequency of sensing since both sensor systems generally have sufficient photometric sensitivity. The chemical parameters of the harbor water were found to be correlated to the optical properties for two stations investigated in detail.

  14. A unique facility for V/STOL aircraft hover testing. [Langley Impact Dynamics Research Facility

    NASA Technical Reports Server (NTRS)

    Culpepper, R. G.; Murphy, R. D.; Gillespie, E. A.; Lane, A. G.

    1979-01-01

    The Langley Impact Dynamics Research Facility (IDRF) was modified to obtain static force and moment data and to allow assessment of aircraft handling qualities during dynamic tethered hover flight. Test probe procedures were also established. Static lift and control measurements obtained are presented along with results of limited dynamic tethered hover flight.

  15. Development of control laws for a flight test maneuver autopilot for an F-15 aircraft

    NASA Technical Reports Server (NTRS)

    Alag, G. S.; Duke, E. L.

    1985-01-01

    An autopilot can be used to provide precise control to meet the demanding requirements of flight research maneuvers with high-performance aircraft. This paper presents the development of control laws within the context of flight test maneuver requirements. The control laws are developed using eigensystem assignment and command generator tracking. The eigenvalues and eigenvectors are chosen to provide the necessary handling qualities, while the command generator tracking enables the tracking of a specified state during the maneuver. The effectiveness of the control laws is illustrated by their application to an F-15 aircraft to ensure acceptable aircraft performance during a maneuver.

  16. Development of control laws for a flight test maneuver autopilot for an F-15 aircraft

    NASA Technical Reports Server (NTRS)

    Alag, G. S.; Duke, E. L.

    1985-01-01

    An autopilot can be used to provide precise control to meet the demanding requirements of flight research maneuvers with high-performance aircraft. The development of control laws within the context of flight test maneuver requirements is discussed. The control laws are developed using eigensystem assignment and command generator tracking. The eigenvalues and eigenvectors are chosen to provide the necessary handling qualities, while the command generator tracking enables the tracking of a specified state during the maneuver. The effectiveness of the control laws is illustrated by their application to an F-15 aircraft to ensure acceptable aircraft performance during a maneuver.

  17. The effect of water supply, handling and usage on water quality in relation to health indices in a developing community in South Africa.

    PubMed

    Genthe, B; Strauss, N; Vundule, C; Maforah, F; Seager, J

    1995-09-01

    This study examined the relationship between the quality of water consumed by people in a developing community in South Africa, and health outcomes for diarrhea. Water sources included no formal water supply, communal taps used by over 100 people, outdoor taps on individual plots, and indoor taps. The aim of this 3-year study was to determine water quality at point of collection, to examine patterns of water usage, and to determine the health consequences. This was a case control study and epidemiological assessment. The sample included over 300 households. Cases included pre-school children with severe diarrhea who visited a health facility in the study area. Interviews were conducted to determine hygiene, sanitation, education, and socioeconomic information. Controls of similar age and type of water supply were obtained from neighborhoods in the study area. Findings indicate that water, based on microbiological assay, was of good quality and complied with the South African Bureau of Standards. Water was significantly more contaminated after handling and storage compared to point of source. Cases and controls had equally poor water quality after collection and storage. Control indoor cases had higher levels of E. coli. There was a strong association between diarrhea and the attendance at a day care center. Increased risk of diarrhea was associated with poor kitchen hygiene and low levels of knowledge about hygiene and diarrhea prevention. Communal tap facilities had lower water quality than private taps.

  18. Control Reallocation Strategies for Damage Adaptation in Transport Class Aircraft

    NASA Technical Reports Server (NTRS)

    Gundy-Burlet, Karen; Krishnakumar, K.; Limes, Greg; Bryant, Don

    2003-01-01

    This paper examines the feasibility, potential benefits and implementation issues associated with retrofitting a neural-adaptive flight control system (NFCS) to existing transport aircraft, including both cable/hydraulic and fly-by-wire configurations. NFCS uses a neural network based direct adaptive control approach for applying alternate sources of control authority in the presence of damage or failures in order to achieve desired flight control performance. Neural networks are used to provide consistent handling qualities across flight conditions, adapt to changes in aircraft dynamics and to make the controller easy to apply when implemented on different aircraft. Full-motion piloted simulation studies were performed on two different transport models: the Boeing 747-400 and the Boeing C-17. Subjects included NASA, Air Force and commercial airline pilots. Results demonstrate the potential for improving handing qualities and significantly increased survivability rates under various simulated failure conditions.

  19. Hypersonic reconnaissance aircraft

    NASA Technical Reports Server (NTRS)

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

    1992-01-01

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

  20. Complexity and Pilot Workload Metrics for the Evaluation of Adaptive Flight Controls on a Full Scale Piloted Aircraft

    NASA Technical Reports Server (NTRS)

    Hanson, Curt; Schaefer, Jacob; Burken, John J.; Larson, David; Johnson, Marcus

    2014-01-01

    Flight research has shown the effectiveness of adaptive flight controls for improving aircraft safety and performance in the presence of uncertainties. The National Aeronautics and Space Administration's (NASA)'s Integrated Resilient Aircraft Control (IRAC) project designed and conducted a series of flight experiments to study the impact of variations in adaptive controller design complexity on performance and handling qualities. A novel complexity metric was devised to compare the degrees of simplicity achieved in three variations of a model reference adaptive controller (MRAC) for NASA's F-18 (McDonnell Douglas, now The Boeing Company, Chicago, Illinois) Full-Scale Advanced Systems Testbed (Gen-2A) aircraft. The complexity measures of these controllers are also compared to that of an earlier MRAC design for NASA's Intelligent Flight Control System (IFCS) project and flown on a highly modified F-15 aircraft (McDonnell Douglas, now The Boeing Company, Chicago, Illinois). Pilot comments during the IRAC research flights pointed to the importance of workload on handling qualities ratings for failure and damage scenarios. Modifications to existing pilot aggressiveness and duty cycle metrics are presented and applied to the IRAC controllers. Finally, while adaptive controllers may alleviate the effects of failures or damage on an aircraft's handling qualities, they also have the potential to introduce annoying changes to the flight dynamics or to the operation of aircraft systems. A nuisance rating scale is presented for the categorization of nuisance side-effects of adaptive controllers.

  1. Design of a flight control system for a highly maneuverable aircraft using mu synthesis

    NASA Technical Reports Server (NTRS)

    Reiner, Jacob; Balas, Gary J.; Garrard, William L.

    1993-01-01

    This paper presents a methodology for the design of longitudinal controllers for high performance aircraft operating over large ranges of angle of attack. The technique used for controller design is structured singular value or mu synthesis. The controller is designed to minimize the weighted H-infinity norm of the error between the aircraft response and the desired handling quality specifications without saturating the control actuators. The mu synthesis procedure ensures that the stability and performance of the aircraft is robust to parameter variations and modeling uncertainties included in the design model. Nonlinear simulations demonstrate that the controller satisfies handling quality requirements and provides excellent tracking of pilot inputs over a wide range of transient angles of attack and Mach number.

  2. Hydraulic fluids and jet engine oil: pyrolysis and aircraft air quality.

    PubMed

    van Netten, C; Leung, V

    2001-01-01

    Incidents of smoke in aircraft cabins often result from jet engine oil and/or hydraulic fluid that leaks into ventilation air, which can be subjected to temperatures that exceed 500 degrees C. Exposed flight-crew members have reported symptoms, including dizziness, nausea, disorientation, blurred vision, and tingling in the legs and arms. In this study, the authors investigated pyrolysis products of one jet engine oil and two hydraulic fluids at 525 degrees C. Engine oil was an important source of carbon monoxide. Volatile agents and organophosphate constituents were released from all the agents tested; however, the neurotoxin trimethyl propane phosphate was not found. The authors hypothesized that localized condensation of pyrolysis products in ventilation ducts, followed by mobilization when cabin heat demand was high, accounted for mid-flight incidents. The authors recommended that carbon monoxide data be logged continuously to capture levels during future incidents.

  3. Review of evolving trends in blended wing body aircraft design

    NASA Astrophysics Data System (ADS)

    Okonkwo, Paul; Smith, Howard

    2016-04-01

    The desire to produce environmentally friendly aircraft that is aerodynamically efficient and capable of conveying large number of passengers over long ranges at reduced direct operating cost led aircraft designers to develop the Blended Wing Body (BWB) aircraft concept. The BWB aircraft represents a paradigm shift in the design of aircraft. The design provides aerodynamics and environmental benefits and is suitable for the integration of advanced systems and concepts like laminar flow technology, jet flaps and distributed propulsion. However, despite these benefits, the BWB is yet to be developed for commercial air transport due to several challenges. This paper reviews emerging trends in BWB aircraft design highlighting design challenges that have hindered the development of a BWB passenger transport aircraft. The study finds that in order to harness the advantages and reduce the deficiencies of a tightly coupled configuration like the BWB, a multidisciplinary design synthesis optimisation should be conducted with good handling and ride quality as objective functions within acceptable direct operating cost and noise bounds.

  4. Ride quality - An exploratory study and criteria development. [visual motion simulator measurement of response ratings of ride quality of aircraft

    NASA Technical Reports Server (NTRS)

    Stone, R. W., Jr.

    1974-01-01

    The Langley six degree of freedom visual motion simulator has been used to measure subjective response ratings of the ride quality of eight segments of flight, representative of a wide variation in comfort estimates. The results indicate that the use of simulators for this purpose appears promising. A preliminary approach for the development of criteria for ride quality ratings based on psychophysical precepts is included.

  5. Tests and analyses applicable to passenger ride quality of large transport aircraft

    NASA Technical Reports Server (NTRS)

    Holloway, R. B.; Brumaghin, S. H.

    1972-01-01

    A test program was undertaken to determine airline passenger reaction to vibration environments that might be encountered in a supersonic transport or other large commercial jet aircraft. The principal problem addressed was to determine accelerations of vertical and lateral vibration that people find objectionable. Further questions experimentally posed were: (1) what is the relationship between human reactions to vertical and lateral vibration, (2) to single- and combined-frequency vibration, and (3) to single- and combined-axis vibration? Interest was confined to reactions to vibration in the frequency range of 0.20 to 7.0 Hz, a range typical of the vibration environment of a large airplane. Results indicated an increasing sensitivity to vertical vibration as frequency was increased from 1.0 to 7.0 Hz. Subjects were found most sensitive to lateral vibration in the 1.0 to 3.0 Hz range. There was a nearly linear decrease in sensitivity as frequency of lateral vibration was increased from 3.0 to 7.0 Hz.

  6. Analyses and tests of the B-1 aircraft structural mode control system

    NASA Technical Reports Server (NTRS)

    Wykes, J. H.; Byar, T. R.; Macmiller, C. J.; Greek, D. C.

    1980-01-01

    Analyses and flight tests of the B-1 structural mode control system (SMCS) are presented. Improvements in the total dynamic response of a flexible aircraft and the benefits to ride qualities, handling qualities, crew efficiency, and reduced dynamic loads on the primary structures, were investigated. The effectiveness and the performance of the SMCS, which uses small aerodynamic surfaces at the vehicle nose to provide damping to the structural modes, were evaluated.

  7. Intelligent Control Approaches for Aircraft Applications

    NASA Technical Reports Server (NTRS)

    Gundy-Burlet, Karen; KrishnaKumar, K.; Soloway, Don; Kaneshige, John; Clancy, Daniel (Technical Monitor)

    2001-01-01

    This paper presents an overview of various intelligent control technologies currently being developed and studied under the Intelligent Flight Control (IFC) program at the NASA Ames Research Center. The main objective of the intelligent flight control program is to develop the next generation of flight controllers for the purpose of automatically compensating for a broad spectrum of damaged or malfunctioning aircraft components and to reduce control law development cost and time. The approaches being examined include: (a) direct adaptive dynamic inverse controller and (b) an adaptive critic-based dynamic inverse controller. These approaches can utilize, but do not require, fault detection and isolation information. Piloted simulation studies are performed to examine if the intelligent flight control techniques adequately: 1) Match flying qualities of modern fly-by-wire flight controllers under nominal conditions; 2) Improve performance under failure conditions when sufficient control authority is available; and 3) Achieve consistent handling qualities across the flight envelope and for different aircraft configurations. Results obtained so far demonstrate the potential for improving handling qualities and significantly increasing survivability rates under various simulated failure conditions.

  8. 9 CFR 91.41 - Cleaning and disinfecting of aircraft.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 9 Animals and Animal Products 1 2010-01-01 2010-01-01 false Cleaning and disinfecting of aircraft... INSPECTION AND HANDLING OF LIVESTOCK FOR EXPORTATION Cleaning and Disinfecting of Aircraft § 91.41 Cleaning and disinfecting of aircraft. Prior to loading of animals, the stowage area of aircraft to be used...

  9. 9 CFR 91.41 - Cleaning and disinfecting of aircraft.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 9 Animals and Animal Products 1 2012-01-01 2012-01-01 false Cleaning and disinfecting of aircraft... INSPECTION AND HANDLING OF LIVESTOCK FOR EXPORTATION Cleaning and Disinfecting of Aircraft § 91.41 Cleaning and disinfecting of aircraft. Prior to loading of animals, the stowage area of aircraft to be used...

  10. 9 CFR 91.41 - Cleaning and disinfecting of aircraft.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 9 Animals and Animal Products 1 2013-01-01 2013-01-01 false Cleaning and disinfecting of aircraft... INSPECTION AND HANDLING OF LIVESTOCK FOR EXPORTATION Cleaning and Disinfecting of Aircraft § 91.41 Cleaning and disinfecting of aircraft. Prior to loading of animals, the stowage area of aircraft to be used...

  11. A Program to Improve the Triangulated Surface Mesh Quality Along Aircraft Component Intersections

    NASA Technical Reports Server (NTRS)

    Cliff, Susan E.

    2005-01-01

    A computer program has been developed for improving the quality of unstructured triangulated surface meshes in the vicinity of component intersections. The method relies solely on point removal and edge swapping for improving the triangulations. It can be applied to any lifting surface component such as a wing, canard or horizontal tail component intersected with a fuselage, or it can be applied to a pylon that is intersected with a wing, fuselage or nacelle. The lifting surfaces or pylon are assumed to be aligned in the axial direction with closed trailing edges. The method currently maintains salient edges only at leading and trailing edges of the wing or pylon component. This method should work well for any shape of fuselage that is free of salient edges at the intersection. The method has been successfully demonstrated on a total of 125 different test cases that include both blunt and sharp wing leading edges. The code is targeted for use in the automated environment of numerical optimization where geometric perturbations to individual components can be critical to the aerodynamic performance of a vehicle. Histograms of triangle aspect ratios are reported to assess the quality of the triangles attached to the intersection curves before and after application of the program. Large improvements to the quality of the triangulations were obtained for the 125 test cases; the quality was sufficient for use with an automated tetrahedral mesh generation program that is used as part of an aerodynamic shape optimization method.

  12. Aircraft and satellite monitoring of water quality in Lake Superior near Duluth

    NASA Technical Reports Server (NTRS)

    Scherz, J. P.; Sydor, M.; Vandomelen, J. F.

    1974-01-01

    Satellite images and low altitude aerial photographs often show vivid discolorations in water bodies. Extensive laboratory analysis shows that water reflectance, which causes brightness on aerial images, positively correlates to the water quality parameter of turbidity, which on a particular day correlates to suspended solids. Work with low altitude photography on three overcast days and with ERTS images on five clear days provides positive correlation of image brightness to the high turbidity and solids which are present in Lake Superior near Duluth over 50% of the time. Proper use of aerial images would have shown that an $8,000,000 drinking water intake constructed in the midst of this unpotable, turbid water should have been located 6 miles north in clear, usable water. Noise effects such as skylight reflection, atmospheric effects, and depth penetration also must be understood for operational use of remote sensing for water quality monitoring and are considered in the paper.

  13. 21 CFR 820.140 - Handling.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Handling. 820.140 Section 820.140 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES QUALITY SYSTEM REGULATION Handling, Storage, Distribution, and Installation § 820.140 Handling....

  14. 21 CFR 820.140 - Handling.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Handling. 820.140 Section 820.140 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES QUALITY SYSTEM REGULATION Handling, Storage, Distribution, and Installation § 820.140 Handling....

  15. 21 CFR 820.140 - Handling.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Handling. 820.140 Section 820.140 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES QUALITY SYSTEM REGULATION Handling, Storage, Distribution, and Installation § 820.140 Handling....

  16. Quality Control and Analysis of Microphysical Data Collected in TRMM Aircraft Validation Experiments

    NASA Technical Reports Server (NTRS)

    Heymsfield, Andrew J.

    2004-01-01

    This report summarizes our efforts on the funded project 'Quality Control and Analysis of Microphysical Data Collected in TRMM Airborne Validation Experiments', NASA NAG5-9663, Andrew Heymsfield, P. I. We begin this report by summarizing our activities in FY2000-FY2004. We then present some highlights of our work. The last part of the report lists the publications that have resulted from our funding through this grant.

  17. RTJ-303: Variable geometry, oblique wing supersonic aircraft

    NASA Technical Reports Server (NTRS)

    Antaran, Albert; Belete, Hailu; Dryzmkowski, Mark; Higgins, James; Klenk, Alan; Rienecker, Lisa

    1992-01-01

    This document is a preliminary design of a High Speed Civil Transport (HSCT) named the RTJ-303. It is a 300 passenger, Mach 1.6 transport with a range of 5000 nautical miles. It features four mixed-flow turbofan engines, variable geometry oblique wing, with conventional tail-aft control surfaces. The preliminary cost analysis for a production of 300 aircraft shows that flyaway cost would be 183 million dollars (1992) per aircraft. The aircraft uses standard jet fuel and requires no special materials to handle aerodynamic heating in flight because the stagnation temperatures are approximately 130 degrees Fahrenheit in the supersonic cruise condition. It should be stressed that this aircraft could be built with today's technology and does not rely on vague and uncertain assumptions of technology advances. Included in this report are sections discussing the details of the preliminary design sequence including the mission to be performed, operational and performance constraints, the aircraft configuration and the tradeoffs of the final choice, wing design, a detailed fuselage design, empennage design, sizing of tail geometry, and selection of control surfaces, a discussion on propulsion system/inlet choice and their position on the aircraft, landing gear design including a look at tire selection, tip-over criterion, pavement loading, and retraction kinematics, structures design including load determination, and materials selection, aircraft performance, a look at stability and handling qualities, systems layout including location of key components, operations requirements maintenance characteristics, a preliminary cost analysis, and conclusions made regarding the design, and recommendations for further study.

  18. Air handling units for hospitals.

    PubMed

    Amoroso, V; Gjestvang, R

    1989-10-01

    Air handling units should provide proper quality and conditioned air to various hospital areas. Unit capacity should be able to meet limited space functionality or load changes as well as any smoke control requirements. System components should be readily accessible and appropriate for spaces served. In summary, engineers should consider the following: Environmental design criteria for area being served Components desired Unit type required Economic issues affecting design. Using this approach, design engineers can design hospital air handling units methodically and logically.

  19. Development and Flight Testing of a Neural Network Based Flight Control System on the NF-15B Aircraft

    NASA Technical Reports Server (NTRS)

    Bomben, Craig R.; Smolka, James W.; Bosworth, John T.; Silliams-Hayes, Peggy S.; Burken, John J.; Larson, Richard R.; Buschbacher, Mark J.; Maliska, Heather A.

    2006-01-01

    The Intelligent Flight Control System (IFCS) project at the NASA Dryden Flight Research Center, Edwards AFB, CA, has been investigating the use of neural network based adaptive control on a unique NF-15B test aircraft. The IFCS neural network is a software processor that stores measured aircraft response information to dynamically alter flight control gains. In 2006, the neural network was engaged and allowed to learn in real time to dynamically alter the aircraft handling qualities characteristics in the presence of actual aerodynamic failure conditions injected into the aircraft through the flight control system. The use of neural network and similar adaptive technologies in the design of highly fault and damage tolerant flight control systems shows promise in making future aircraft far more survivable than current technology allows. This paper will present the results of the IFCS flight test program conducted at the NASA Dryden Flight Research Center in 2006, with emphasis on challenges encountered and lessons learned.

  20. Assessing Aircraft Susceptibility to Nonlinear Aircraft-Pilot Coupling/Pilot-Induced Oscillations

    NASA Technical Reports Server (NTRS)

    Hess, R.A.; Stout, P. W.

    1997-01-01

    A unified approach for assessing aircraft susceptibility to aircraft-pilot coupling (or pilot-induced oscillations) which was previously reported in the literature and applied to linear systems is extended to nonlinear systems, with emphasis upon vehicles with actuator rate saturation. The linear methodology provided a tool for predicting: (1) handling qualities levels, (2) pilot-induced oscillation rating levels and (3) a frequency range in which pilot-induced oscillations are likely to occur. The extension to nonlinear systems provides a methodology for predicting the latter two quantities. Eight examples are presented to illustrate the use of the technique. The dearth of experimental flight-test data involving systematic variation and assessment of the effects of actuator rate limits presently prevents a more thorough evaluation of the methodology.

  1. Neighborhood-scale air quality impacts of emissions from motor vehicles and aircraft

    NASA Astrophysics Data System (ADS)

    Choi, Wonsik; Hu, Shishan; He, Meilu; Kozawa, Kathleen; Mara, Steve; Winer, Arthur M.; Paulson, Suzanne E.

    2013-12-01

    A mobile monitoring platform (MMP) was used to measure real-time air pollutant concentrations in different built environments of Boyle Heights (BH, a lower-income community enclosed by several freeways); Downtown Los Angeles (DTLA, adjacent to BH with taller buildings and surrounded by several freeways); and West Los Angeles (WLA, an affluent community traversed by two freeways) in summer afternoons of 2008 and 2011 (only for WLA). Significant inter-community and less significant but observable intra-community differences in traffic-related pollutant concentrations were observed both in the residential neighborhoods studied and on their arterial roadways between BH, DTLA, and WLA, particularly for ultrafine particles (UFP). HEV, defined as vehicles creating plumes with concentrations more than three standard deviations from the adjusted local baseline, were encountered during 6-13% of sampling time, during which they accounted for 17-55% of total UFP concentrations both on arterial roadways and in residential neighborhoods. If instead a single threshold value is used to define HEVs in all areas, HEV's were calculated to make larger contributions to UFP concentrations in BH than other communities by factors of 2-10 or more. Santa Monica Airport located in WLA appears to be a significant source for elevated UFP concentrations in nearby residential neighborhoods 80-400 m downwind. In the WLA area, we also showed, on a neighborhood scale, striking and immediate reductions in particulate pollution (˜70% reductions in both UFP and, somewhat surprisingly, PM2.5), corresponding to dramatic decreases in traffic densities during an I-405 closure event (“Carmageddon”) compared to non-closure Saturday levels. Although pollution reduction due to decreased traffic is not unexpected, this dramatic improvement in particulate pollution provides clear evidence air quality can be improved through strategies such as heavy-duty-diesel vehicle retrofits, earlier retirement of HEV

  2. Development of the remote-handled transuranic waste radioassay data quality objectives. An evaluation of RH-TRU waste inventories, characteristics, radioassay methods and capabilities

    SciTech Connect

    Meeks, A.M.; Chapman, J.A.

    1997-09-01

    The Waste Isolation Pilot Plant will accept remote-handled transuranic waste as early as October of 2001. Several tasks must be accomplished to meet this schedule, one of which is the development of Data Quality Objectives (DQOs) and corresponding Quality Assurance Objectives (QAOs) for the assay of radioisotopes in RH-TRU waste. Oak Ridge National Laboratory (ORNL) was assigned the task of providing to the DOE QAO, information necessary to aide in the development of DQOs for the radioassay of RH-TRU waste. Consistent with the DQO process, information needed and presented in this report includes: identification of RH-TRU generator site radionuclide data that may have potential significance to the performance of the WIPP repository or transportation requirements; evaluation of existing methods to measure the identified isotopic and quantitative radionuclide data; evaluation of existing data as a function of site waste streams using documented site information on fuel burnup, radioisotope processing and reprocessing, special research and development activities, measurement collection efforts, and acceptable knowledge; and the current status of technologies and capabilities at site facilities for the identification and assay of radionuclides in RH-TRU waste streams. This report is intended to provide guidance in developing the RH-TRU waste radioassay DQOs, first by establishing a baseline from which to work, second, by identifying needs to fill in the gaps between what is known and achievable today and that which will be required before DQOs can be formulated, and third, by recommending measures that should be taken to assure that the DQOs in fact balance risk and cost with an achievable degree of certainty.

  3. Conceptual design study of a Harrier V/STOL research aircraft

    NASA Technical Reports Server (NTRS)

    Bode, W. E.; Berger, R. L.; Elmore, G. A.; Lacey, T. R.

    1978-01-01

    MCAIR recently completed a conceptual design study to define modification approaches to, and derive planning prices for the conversion of a two place Harrier to a V/STOL control, display and guidance research aircraft. Control concepts such as rate damping, attitude stabilization, velocity command, and cockpit controllers are to be demonstrated. Display formats will also be investigated, and landing, navigation and guidance systems flight tested. The rear cockpit is modified such that it can be quickly adapted to faithfully simulate the controls, displays and handling qualities of a Type A or Type B V/STOL. The safety pilot always has take command capability. The modifications studied fall into two categories: basic modifications and optional modifications. Technical descriptions of the basic modifications and of the optional modifications are presented. The modification plan and schedule as well as the test plan and schedule are presented. The failure mode and effects analysis, aircraft performance, aircraft weight, and aircraft support are discussed.

  4. Theoretical linear approach to the combined man-manipulator system in manual control of an aircraft

    NASA Technical Reports Server (NTRS)

    Brauser, K.

    1981-01-01

    An approach to the calculation of the dynamic characteristics of the combined man manipulator system in manual aircraft control was derived from a model of the neuromuscular system. This model combines the neuromuscular properties of man with the physical properties of the manipulator system which is introduced as pilot manipulator model into the manual aircraft control. The assumption of man as a quasilinear and time invariant control operator adapted to operating states, depending on the flight phases, of the control system gives rise to interesting solutions of the frequency domain transfer functions of both the man manipulator system and the closed loop pilot aircraft control system. It is shown that it is necessary to introduce the complete precision pilot manipulator model into the closed loop pilot aircraft transfer function in order to understand the well known handling quality criteria, and to derive these criteria directly from human operator properties.

  5. Lake Michigan and Lake Superior air quality: The 1994-2003 LADCO Aircraft Project (LAP)

    NASA Astrophysics Data System (ADS)

    Foley, T. A.; Betterton, E. A.; Jacko, R.; Hillery, J.

    2011-12-01

    The goal of the 1994 to 2003 LADCO Airplane Project (LAP) was to study ozone formation over Lake Michigan so that equitable regional control strategies could be devised. During the ten year LAP campaign, a total of 328 flights were flown on 81 days over Lake Michigan and its southern and western boundaries. LAP also monitored air quality over Lake Superior and other areas in the Midwestern and southern United States. From 2001 to 2003, 117 flights were conducted over Lake Superior, Isle Royale National Park, Painted Rocks National Lakeshore and the Seeney National Wildlife Refuge in Michigan. 63 flights were conducted over St. Louis and 58 flights over the Dolly Sods Wilderness Area in West Virginia. We are looking for collaborators to help us analyze this vast data archive. Our first paper (Atmospheric Environment 45 (2011) 3192-3202) documented the project and presented results of our ozone analysis. Our results support the hypothesis of Dye et al. (1995), who found that the atmosphere over Lake Michigan is stable in the summer due to the air water temperature difference, which creates an efficient reaction chamber for ozone formation. They also hypothesized that the southwest winds characteristic of ozone-conducive conditions transport ozone further north over the lake before it crosses the shoreline onto land. We found that below 200 m above the lake, ozone formation is VOC-limited in the morning and becomes NOx limited in the afternoon. Above 200 m, ozone formation is NOx-limited throughout the day. The onshore NOx and VOC diurnal cycles peak during the early morning rush hour and are clearly linked to traffic patterns. Over the lake, VOC and NOy concentrations peak during the mid-morning rather than the early morning, supporting the hypothesis that the land breeze transports VOC and NOy over the lake. The diurnal NOx pattern over Lake Michigan is less clearly defined than the VOC pattern possibly as a result of emissions from five coal-burning power plants

  6. 14 CFR 25.489 - Ground handling conditions.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Ground handling conditions. 25.489 Section 25.489 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT... ground handling conditions). No wing lift may be considered. The shock absorbers and tires may be...

  7. The Effect of Yaw Coupling in Turning Maneuvers of Large Transport Aircraft

    NASA Technical Reports Server (NTRS)

    McNeill, Walter E.; Innis, Robert C.

    1965-01-01

    A study has been made, using a piloted moving simulator, of the effects of the yaw-coupling parameters N(sub p) and N(sub delta(sub a) on the lateral-directional handling qualities of a large transport airplane at landing-approach airspeed. It is shown that the desirable combinations of these parameters tend to be more proverse when compared with values typical of current aircraft. Results of flight tests in a large variable-stability jet transport showed trends which were similar to those of the simulator data. Areas of minor disagreement, which were traced to differences in airplane geometry, indicate that pilot consciousness of side acceleration forces can be an important factor in handling qualities of future long-nosed transport aircraft.

  8. The Ultra Light Aircraft Testing

    NASA Technical Reports Server (NTRS)

    Smith, Howard W.

    1993-01-01

    The final report for grant NAG1-345 is presented. Recently, the bulk of the work that the grant has supported has been in the areas of ride quality and the structural analysis and testing of ultralight aircraft. The ride quality work ended in May 1989. Hence, the papers presented in this final report are concerned with ultralight aircraft.

  9. Immunity-Based Aircraft Fault Detection System

    NASA Technical Reports Server (NTRS)

    Dasgupta, D.; KrishnaKumar, K.; Wong, D.; Berry, M.

    2004-01-01

    In the study reported in this paper, we have developed and applied an Artificial Immune System (AIS) algorithm for aircraft fault detection, as an extension to a previous work on intelligent flight control (IFC). Though the prior studies had established the benefits of IFC, one area of weakness that needed to be strengthened was the control dead band induced by commanding a failed surface. Since the IFC approach uses fault accommodation with no detection, the dead band, although it reduces over time due to learning, is present and causes degradation in handling qualities. If the failure can be identified, this dead band can be further A ed to ensure rapid fault accommodation and better handling qualities. The paper describes the application of an immunity-based approach that can detect a broad spectrum of known and unforeseen failures. The approach incorporates the knowledge of the normal operational behavior of the aircraft from sensory data, and probabilistically generates a set of pattern detectors that can detect any abnormalities (including faults) in the behavior pattern indicating unsafe in-flight operation. We developed a tool called MILD (Multi-level Immune Learning Detection) based on a real-valued negative selection algorithm that can generate a small number of specialized detectors (as signatures of known failure conditions) and a larger set of generalized detectors for unknown (or possible) fault conditions. Once the fault is detected and identified, an adaptive control system would use this detection information to stabilize the aircraft by utilizing available resources (control surfaces). We experimented with data sets collected under normal and various simulated failure conditions using a piloted motion-base simulation facility. The reported results are from a collection of test cases that reflect the performance of the proposed immunity-based fault detection algorithm.

  10. A plume-in-grid approach to characterize air quality impacts of aircraft emissions at the Hartsfield-Jackson Atlanta International Airport

    NASA Astrophysics Data System (ADS)

    Rissman, J.; Arunachalam, S.; Woody, M.; West, J. J.; BenDor, T.; Binkowski, F. S.

    2013-09-01

    This study examined the impacts of aircraft emissions during the landing and takeoff cycle on PM2.5 concentrations during the months of June and July 2002 at the Hartsfield-Jackson Atlanta International Airport. Primary and secondary pollutants were modeled using the Advanced Modeling System for Transport, Emissions, Reactions, and Deposition of Atmospheric Matter (AMSTERDAM). AMSTERDAM is a modified version of the Community Multiscale Air Quality (CMAQ) model that incorporates a plume-in-grid process to simulate emissions sources of interest at a finer scale than can be achieved using CMAQ's model grid. Three fundamental issues were investigated: the effects of aircraft on PM2.5 concentrations throughout northern Georgia, the differences resulting from use of AMSTERDAM's plume-in-grid process rather than a traditional CMAQ simulation, and the concentrations observed in aircraft plumes at subgrid scales. Comparison of model results with an air quality monitor located in the vicinity of the airport found that normalized mean bias ranges from -77.5% to 6.2% and normalized mean error ranges from 40.4% to 77.5%, varying by species. Aircraft influence average PM2.5 concentrations by up to 0.232 μg m-3 near the airport and by 0.001-0.007 μg m-3 throughout the Atlanta metro area. The plume-in-grid process increases concentrations of secondary PM pollutants by 0.005-0.020 μg m-3 (compared to the traditional grid-based treatment) but reduces the concentration of non-reactive primary PM pollutants by up to 0.010 μg m-3, with changes concentrated near the airport. Examination of subgrid-scale results indicates that median aircraft contribution to grid cells is higher than median puff concentration in the airport's grid cell and outside of a 20 km × 20 km square area centered on the airport, while in a 12 km × 12 km square ring centered on the airport, puffs have median concentrations over an order of magnitude higher than aircraft contribution to the grid cells. Maximum

  11. A review of US Army aircrew-aircraft integration research programs

    NASA Technical Reports Server (NTRS)

    Key, D. C.; Aiken, E. W.

    1984-01-01

    If the U.S. Army's desire to develop a one crew version of the Light Helicopter Family (LHX) helicopter is to be realized, both flightpath management and mission management will have to be performed by one crew. Flightpath management, the helicopter pilot, and the handling qualities of the helicopter were discussed. In addition, mission management, the helicopter pilot, and pilot control/display interface were considered. Aircrew-aircraft integration plans and programs were reviewed.

  12. Conceptual design of an aircraft automated coating removal system

    SciTech Connect

    Baker, J.E.; Draper, J.V.; Pin, F.G.; Primm, A.H.; Shekhar, S.

    1996-05-01

    Paint stripping of the U.S. Air Force`s large transport aircrafts is currently a labor-intensive, manual process. Significant reductions in costs, personnel and turnaround time can be accomplished by the judicious use of automation in some process tasks. This paper presents the conceptual design of a coating removal systems for the tail surfaces of the C-5 plane. Emphasis is placed on the technology selection to optimize human-automation synergy with respect to overall costs, throughput, quality, safety, and reliability. Trade- offs between field-proven vs. research-requiring technologies, and between expected gain vs. cost and complexity, have led to a conceptual design which is semi-autonomous (relying on the human for task specification and disturbance handling) yet incorporates sensor- based automation (for sweep path generation and tracking, surface following, stripping quality control and tape/breach handling).

  13. Effect of stabilization on VTOL aircraft in hovering flight

    NASA Technical Reports Server (NTRS)

    Greif, R. K.; Fry, E. B.; Gerdes, R. M.; Gossett, T. D.

    1972-01-01

    A motion simulator study was conducted to determine the effects of roll and pitch stabilization on the handling qualities and control power requirements of VTOL aircraft during hover and short-distance maneuvering flight. Three levels of stabilization complexity were compared: (1) no stabilization, (2) rate stabilization, and (3) attitude stabilization. Control sensitivities and stabilization gains were optimized prior to comparison. Results are presented to show how the optimum systems were determined and how they compared with each other at different levels of control power. Comparisons were made both in calm air and in the presence of roll disturbances. Results indicate the attitude-stabilized system provides the best handling qualities for the least amount of control power.

  14. Microwave imaging of aircraft

    NASA Astrophysics Data System (ADS)

    Steinberg, Bernard D.

    1988-12-01

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

  15. Alternative jet aircraft fuels

    NASA Technical Reports Server (NTRS)

    Grobman, J.

    1979-01-01

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

  16. A plume-in-grid approach to characterize air quality impacts of aircraft emissions at the Hartsfield-Jackson Atlanta International Airport

    NASA Astrophysics Data System (ADS)

    Rissman, J.; Arunachalam, S.; Woody, M.; West, J. J.; BenDor, T.; Binkowski, F. S.

    2013-01-01

    This study examined the impacts of aircraft emissions during the landing and takeoff cycle on PM2.5 concentrations during the months of June 2002 and July 2002 at the Hartsfield-Jackson Atlanta International Airport. Primary and secondary pollutants were modeled using the Advanced Modeling System for Transport, Emissions, Reactions, and Deposition of Atmospheric Matter (AMSTERDAM). AMSTERDAM is a modified version of the Community Multiscale Air Quality (CMAQ) model that incorporates a plume-in-grid process to simulate emissions sources of interest at a finer scale than can be achieved using CMAQ's model grid. Three fundamental issues were investigated: the effects of aircraft on PM2.5 concentrations throughout northern Georgia, the differences resulting from use of AMSTERDAM's plume-in-grid process rather than a traditional CMAQ simulation, and the concentrations observed in aircraft plumes at sub-grid scales. Comparison of model results with an air quality monitor located in the vicinity of the airport found that normalized mean bias ranges from -77.5% to 6.2% and normalized mean error ranges from 40.4% to 77.5%, varying by species. Aircraft influence average PM2.5 concentrations by up to 0.232 μg m-3 near the airport and by 0.001-0.007 μg m-3 throughout the Atlanta metro area. The plume-in-grid process increases concentrations of secondary PM pollutants by 0.005-0.020 μg m-3 (compared to the traditional grid-based treatment) but reduces the concentration of non-reactive primary PM pollutants by up to 0.010 μg m-3, with changes concentrated near the airport. Examination of sub-grid scale results indicates that puffs within 20 km of the airport often have average PM2.5 concentrations one order of magnitude higher than aircraft contribution to the grid cells containing those puffs, and within 1-4 km of emitters, puffs may have PM2.5 concentrations 3 orders of magnitude greater than the aircraft contribution to their grid cells. 21% of all aircraft-related puffs

  17. Transportation and handling loads

    NASA Technical Reports Server (NTRS)

    Ostrem, F. E.

    1971-01-01

    Criteria and recommended practices are presented for the prediction and verification of transportation and handling loads for the space vehicle structure and for monitoring these loads during transportation and handling of the vehicle or major vehicle segments. Elements of the transportation and handling systems, and the forcing functions and associated loads are described. The forcing functions for common carriers and typical handling devices are assessed, and emphasis is given to the assessment of loads at the points where the space vehicle is supported during transportation and handling. Factors which must be considered when predicting the loads include the transportation and handling medium; type of handling fixture; transport vehicle speed; types of terrain; weather (changes in pressure of temperature, wind, etc.); and dynamics of the transportation modes or handling devices (acceleration, deceleration, and rotations of the transporter or handling device).

  18. Quantitative analysis of aircraft multispectral-scanner data and mapping of water-quality parameters in the James River in Virginia

    NASA Technical Reports Server (NTRS)

    Johnson, R. W.; Bahn, G. S.

    1977-01-01

    Statistical analysis techniques were applied to develop quantitative relationships between in situ river measurements and the remotely sensed data that were obtained over the James River in Virginia on 28 May 1974. The remotely sensed data were collected with a multispectral scanner and with photographs taken from an aircraft platform. Concentration differences among water quality parameters such as suspended sediment, chlorophyll a, and nutrients indicated significant spectral variations. Calibrated equations from the multiple regression analysis were used to develop maps that indicated the quantitative distributions of water quality parameters and the dispersion characteristics of a pollutant plume entering the turbid river system. Results from further analyses that use only three preselected multispectral scanner bands of data indicated that regression coefficients and standard errors of estimate were not appreciably degraded compared with results from the 10-band analysis.

  19. Closed-Loop System Identification Experience for Flight Control Law and Flying Qualities Evaluation of a High Performance Fighter Aircraft

    NASA Technical Reports Server (NTRS)

    Murphy, Patrick C.

    1996-01-01

    This paper highlights some of the results and issues associated with estimating models to evaluate control law design methods and design criteria for advanced high performance aircraft. Experimental fighter aircraft such as the NASA-High Alpha Research Vehicle (HARV) have the capability to maneuver at very high angles of attack where nonlinear aerodynamics often predominate. HARV is an experimental F/A-18, configured with thrust vectoring and conformal actuated nose strakes. Identifying closed-loop models for this type of aircraft can be made difficult by nonlinearities and high order characteristics of the system. In this paper, only lateral-directional axes are considered since the lateral-directional control law was specifically designed to produce classical airplane responses normally expected with low-order, rigid-body systems. Evaluation of the control design methodology was made using low-order equivalent systems determined from flight and simulation. This allowed comparison of the closed-loop rigid-body dynamics achieved in flight with that designed in simulation. In flight, the On Board Excitation System was used to apply optimal inputs to lateral stick and pedals at five angles at attack : 5, 20, 30, 45, and 60 degrees. Data analysis and closed-loop model identification were done using frequency domain maximum likelihood. The structure of identified models was a linear state-space model reflecting classical 4th-order airplane dynamics. Input time delays associated with the high-order controller and aircraft system were accounted for in data preprocessing. A comparison of flight estimated models with small perturbation linear design models highlighted nonlinearities in the system and indicated that the closed-loop rigid-body dynamics were sensitive to input amplitudes at 20 and 30 degrees angle of attack.

  20. Closed-Loop System Identification Experience for Flight Control Law and Flying Qualities Evaluation of a High Performance Fighter Aircraft

    NASA Technical Reports Server (NTRS)

    Murphy, Patrick C.

    1999-01-01

    This paper highlights some of the results and issues associated with estimating models to evaluate control law design methods and design criteria for advanced high performance aircraft. Experimental fighter aircraft such as the NASA High Alpha Research Vehicle (HARV) have the capability to maneuver at very high angles of attack where nonlinear aerodynamics often predominate. HARV is an experimental F/A-18, configured with thrust vectoring and conformal actuated nose strakes. Identifying closed-loop models for this type of aircraft can be made difficult by nonlinearities and high-order characteristics of the system. In this paper only lateral-directional axes are considered since the lateral-directional control law was specifically designed to produce classical airplane responses normally expected with low-order, rigid-body systems. Evaluation of the control design methodology was made using low-order equivalent systems determined from flight and simulation. This allowed comparison of the closed-loop rigid-body dynamics achieved in flight with that designed in simulation. In flight, the On Board Excitation System was used to apply optimal inputs to lateral stick and pedals at five angles of attack: 5, 20, 30, 45, and 60 degrees. Data analysis and closed-loop model identification were done using frequency domain maximum likelihood. The structure of the identified models was a linear state-space model reflecting classical 4th-order airplane dynamics. Input time delays associated with the high-order controller and aircraft system were accounted for in data preprocessing. A comparison of flight estimated models with small perturbation linear design models highlighted nonlinearities in the system and indicated that the estimated closed-loop rigid-body dynamics were sensitive to input amplitudes at 20 and 30 degrees angle of attack.

  1. Quiet short-haul research aircraft familiarization document, revision 1

    NASA Technical Reports Server (NTRS)

    Eppel, J. C.

    1981-01-01

    The design features and general characteristics of the Quiet Short Haul Research Aircraft are described. Aerodynamic characteristics and performance are discussed based on predictions and early flight test data. Principle airplane systems, including the airborne data acquisition system, are also described. The aircraft was designed and built to fulfill the need for a national research facility to explore the use of upper surface blowing, propulsive lift technology in providing short takeoff and landing capability, and perform advanced experiments in various technical disciplines such as aerodynamics, propulsion, stability and control, handling qualities, avionics and flight control systems, trailing vortex phenomena, acoustics, structure and loads, operating systems, human factors, and airworthiness/certification criteria. An unusually austere approach using experimental shop practices resulted in a low cost and high research capability.

  2. Moving base simulation of an integrated flight and propulsion control system for an ejector-augmentor STOVL aircraft in hover

    NASA Technical Reports Server (NTRS)

    Mcneill, Walter, E.; Chung, William W.; Stortz, Michael W.

    1995-01-01

    A piloted motion simulator evaluation, using the NASA Ames Vertical Motion Simulator, was conducted in support of a NASA Lewis Contractual study of the integration of flight and propulsion systems of a STOVL aircraft. Objectives of the study were to validate the Design Methods for Integrated Control Systems (DMICS) concept, to evaluate the handling qualities, and to assess control power usage. The E-7D ejector-augmentor STOVL fighter design served as the basis for the simulation. Handling-qualities ratings were obtained during precision hover and shipboard landing tasks. Handling-qualities ratings for these tasks ranged from satisfactory to adequate. Further improvement of the design process to fully validate the DMICS concept appears to be warranted.

  3. 7 CFR 996.4 - Handle.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Marketing Agreements and Orders; Fruits, Vegetables, Nuts), DEPARTMENT OF AGRICULTURE MINIMUM QUALITY AND HANDLING STANDARDS FOR... consumption channels of commerce: Provided, That this term does not include sales or deliveries of peanuts...

  4. 7 CFR 996.4 - Handle.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (MARKETING AGREEMENTS AND ORDERS; FRUITS, VEGETABLES, NUTS), DEPARTMENT OF AGRICULTURE MINIMUM QUALITY AND HANDLING STANDARDS FOR... consumption channels of commerce: Provided, That this term does not include sales or deliveries of peanuts...

  5. 7 CFR 996.4 - Handle.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Marketing Agreements and Orders; Fruits, Vegetables, Nuts), DEPARTMENT OF AGRICULTURE MINIMUM QUALITY AND HANDLING STANDARDS FOR... consumption channels of commerce: Provided, That this term does not include sales or deliveries of peanuts...

  6. 7 CFR 996.4 - Handle.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Marketing Agreements and Orders; Fruits, Vegetables, Nuts), DEPARTMENT OF AGRICULTURE MINIMUM QUALITY AND HANDLING STANDARDS FOR... consumption channels of commerce: Provided, That this term does not include sales or deliveries of peanuts...

  7. Feedback control laws for highly maneuverable aircraft

    NASA Technical Reports Server (NTRS)

    Garrard, William L.; Balas, Gary J.

    1992-01-01

    The results of a study of the application of H infinity and mu synthesis techniques to the design of feedback control laws for the longitudinal dynamics of the High Angle of Attack Research Vehicle (HARV) are presented. The objective of this study is to develop methods for the design of feedback control laws which cause the closed loop longitudinal dynamics of the HARV to meet handling quality specifications over the entire flight envelope. Control law designs are based on models of the HARV linearized at various flight conditions. The control laws are evaluated by both linear and nonlinear simulations of typical maneuvers. The fixed gain control laws resulting from both the H infinity and mu synthesis techniques result in excellent performance even when the aircraft performs maneuvers in which the system states vary significantly from their equilibrium design values. Both the H infinity and mu synthesis control laws result in performance which compares favorably with an existing baseline longitudinal control law.

  8. Aircraft recognition and tracking device

    NASA Astrophysics Data System (ADS)

    Filis, Dimitrios P.; Renios, Christos I.

    2011-11-01

    The technology of aircraft recognition and tracking has various applications in all areas of air navigation, be they civil or military, spanning from air traffic control and regulation at civilian airports to anti-aircraft weapon handling and guidance for military purposes.1, 18 The system presented in this thesis is an alternative implementation of identifying and tracking flying objects, which benefits from the optical spectrum by using an optical camera built into a servo motor (pan-tilt unit). More specifically, through the purpose-developed software, when a target (aircraft) enters the field of view of the camera18, it is both detected and identified.5, 22 Then the servo motor, being provided with data on target position and velocity, tracks the aircraft while it is in constant communication with the camera (Fig. 1). All the features are so designed as to operate under real time conditions.

  9. Output model-following control synthesis for an oblique-wing aircraft

    NASA Technical Reports Server (NTRS)

    Pahle, Joseph W.

    1990-01-01

    Recent interest in oblique-wing aircraft has focused on the potential aerodynamic performance advantage of a variable-skew oblique wing over a conventional or symmetric sweep wing. Unfortunately, the resulting asymmetric configuration has significant aerodynamic and inertial cross-coupling between the aircraft longitudinal and lateral-directional axes. Presented here is a decoupling control law synthesis technique that integrates stability augmentation, decoupling, and the direct incorporation of desired handling qualities into an output feedback controller. The proposed design technique uses linear quadratic regulator concepts in the framework of explicit model following. The output feedback strategy used is a suboptimal projection from the state space to the output space. Dynamics are then introduced into the controller to improve steady-state performance and increase system robustness. Closed-loop performance is shown by application of the control laws to the linearized equations of motion and nonlinear simulation of an oblique-wing aircraft.

  10. Frequency-response identification of XV-15 tilt-rotor aircraft dynamics

    NASA Technical Reports Server (NTRS)

    Tischler, Mark B.

    1987-01-01

    The timely design and development of the next generation of tilt-rotor aircraft (JVX) depend heavily on the in-depth understanding of existing XV-15 dynamics and the availability of fully validated simulation models. Previous studies have considered aircraft and simulation trim characteristics, but analyses of basic flight vehicle dynamics were limited to qualitative pilot evaluation. The present study has the following objectives: documentation and evaluation of XV-15 bare-airframe dynamics; comparison of aircraft and simulation responses; and development of a validated transfer-function description of the XV-15 needed for future studies. A nonparametric frequency-response approach is used which does not depend on assumed model order or structure. Transfer-function representations are subsequently derived which fit the frequency responses in the bandwidth of greatest concern for piloted handling-qualities and control-system applications.

  11. XV-15 Tiltrotor Aircraft: 1997 Acoustic Testing

    NASA Technical Reports Server (NTRS)

    Edwards, Bryan D.; Conner, David A.

    2003-01-01

    XV-15 acoustic test is discussed, and measured results are presented. The test was conducted by NASA Langley and Bell Helicopter Textron, Inc., during June - July 1997, at the BHTI test site near Waxahachie, Texas. This was the second in a series of three XV-15 tests to document the acoustic signature of the XV-15 tiltrotor aircraft for a variety of flight conditions and minimize the noise signature during approach. Tradeoffs between flight procedures and the measured noise are presented to illustrate the noise abatement flight procedures. The test objectives were to: (1) support operation of future tiltrotors by further developing and demonstrating low-noise flight profiles, while maintaining acceptable handling and ride qualities, and (2) refine approach profiles, selected from previous (1995) tiltrotor testing, to incorporate Instrument Flight Rules (IFR), handling qualities constraints, operations and tradeoffs with sound. Primary emphasis was given to the approach flight conditions where blade-vortex interaction (BVI) noise dominates, because this condition influences community noise impact more than any other. An understanding of this part of the noise generating process could guide the development of low noise flight operations and increase the tiltrotor's acceptance in the community.

  12. Aircraft Design

    NASA Technical Reports Server (NTRS)

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

    2016-01-01

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

  13. Preliminary simulation of an advanced, hingless rotor XV-15 tilt-rotor aircraft

    NASA Technical Reports Server (NTRS)

    Mcveigh, M. A.

    1976-01-01

    The feasibility of the tilt-rotor concept was verified through investigation of the performance, stability and handling qualities of the XV-15 tilt rotor. The rotors were replaced by advanced-technology fiberglass/composite hingless rotors of larger diameter, combined with an advanced integrated fly-by-wire control system. A parametric simulation model of the HRXV-15 was developed, model was used to define acceptable preliminary ranges of primary and secondary control schedules as functions of the flight parameters, to evaluate performance, flying qualities and structural loads, and to have a Boeing-Vertol pilot conduct a simulated flight test evaluation of the aircraft.

  14. Data Handling and Citizenship

    ERIC Educational Resources Information Center

    Tresidder, Gwen

    2006-01-01

    When marking GCSE data handling coursework, the author was repeatedly reminded just how poor the level of statistical understanding is among students. In response to a feeling that the teaching of handling data topics was limited, the author and her colleague designed a project with Y8 students to try to teach statistics for a deeper…

  15. Aircraft Steels

    DTIC Science & Technology

    2009-02-19

    NAWCADPAX/TR-2009/ 12 AIRCRAFT STEELS by E. U. Lee R. Taylor C. Lei H. C. Sanders 19 February 2009...MARYLAND NAWCADPAX/TR-2009/ 12 19 February 2009 AIRCRAFT STEELS by E. U. Lee R. Taylor C. Lei H. C. Sanders...Prescribed by ANSI Std. Z39-18 NAWCADPAX/TR-2009/ 12 ii SUMMARY Five high strength and four stainless steels have been studied, identifying their

  16. Development of Morphing Aircraft Structure Using SMP

    DTIC Science & Technology

    2010-03-01

    from friction in the thin boundary layer surrounding the aircraft surface. In high speed flight, the parasite drag caused by Swet is very important...for cruising long distance, morphing wings transform to longer span and smaller surface to get high CL/CD ratio. 7 c. Loiter The morphing...During loitering the morphing aircraft transform their wings with more sweep back angle to dash in order to get high speed and handling control

  17. Aircraft trace gas measurements during the London 2012 Olympics: Air quality and emission fluxes derived from sampling upwind and downwind of a megacity

    NASA Astrophysics Data System (ADS)

    Allen, G.; O'Shea, S.; Muller, J.; Jones, B.; O'Sullivan, D.; Lee, J. D.; Bauguitte, S.; Gallagher, M. W.; Percival, C.; Barratt, B.; McQuaid, J. B.; Illingworth, S.

    2013-12-01

    This study presents airborne in situ and remote sensing measurements recorded during July and August 2012, across the period of the London 2012 Summer Olympics and simultaneous with the Clear air for London (ClearfLo) ground-based measurement and modelling campaign. Through long-term (2-year) and intensive observation periods (Winter 2011 and Summer 2012), the ClearfLo programme aims to better understand emissions, as well as the chemical, dynamical and micro-meteorological processes which modulate air quality in the London urban environment - an important risk factor for both acute and chronic health effects. The work presented here focuses on two contrasting case studies within the summer ClearfLo period: 30 July 2012 and 9 August 2012, representing relatively clean background and polluted background cases, respectively, and characterised by well-mixed Atlantic westerly maritime inflow in the former and stagnant air (high pressure) in the latter. Measurements of CO, CO2, CH4, N2O, O3, HCN, and other gases measured on board the UK Facility for Airborne Atmospheric Measurement (FAAM) BAe-146 aircraft will be presented and interpreted, with emphasis on observed concentration gradients and tracer-tracer correlations as well as airmass vertical structure and airmass history upwind and downwind of central London in each case. By applying a simple advective model and making use of vertically resolved thermodynamic and composition data, we are able to derive emission strengths for these gases that are representative of the total enclosed surface area. Example emissions for these two cases range between 6x105 kg(C)/hr and 9x105 kg(C)/hr for CO2, and ~0.6x105 kg(C)/hr for CH4. This airborne sampling methodology highlights the unique utility of aircraft measurements to routinely and climatologically characterise emissions from area sources such as cities, and points to future missions to target localised hotspots and distributed point sources.

  18. CHR -- Character Handling Routines

    NASA Astrophysics Data System (ADS)

    Charles, A. C.; Rees, P. C. T.; Chipperfield, A. J.; Jenness, T.

    This document describes the Character Handling Routine library, CHR, and its use. The CHR library augments the limited character handling facilities provided by the Fortran 77 standard. It offers a range of character handling facilities: from formatting Fortran data types into text strings and the reverse, to higher level functions such as wild card matching, string sorting, paragraph reformatting and justification. The library may be used simply for building text strings for interactive applications or as a basis for more complex text processing applications.

  19. Future of remote handling

    SciTech Connect

    Grisham, D.L.; Lambert, J.E.

    1986-01-01

    The field of remote handling started in the late 1940's and early 1950's with the invention of mechanical master-slave and electromechanical manipulators. That field now consists of three major divisions: (1) conventional remote handling in fixed facilities with shielding windows and mechanical manipulators; (2) large area remote handling using portable equipment, electric master-slave manipulators, and television for viewing; and (3) the field of robotics which is beginning to be applied to repetitive operations on toxic and dangerous materials. All three divisions will continue to develop and evolve over the next decade.

  20. 48 CFR 246.408-71 - Aircraft.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 48 Federal Acquisition Regulations System 3 2013-10-01 2013-10-01 false Aircraft. 246.408-71..., DEPARTMENT OF DEFENSE CONTRACT MANAGEMENT QUALITY ASSURANCE Government Contract Quality Assurance 246.408-71 Aircraft. (a) The Federal Aviation Administration (FAA) has certain responsibilities and prerogatives...

  1. 48 CFR 246.408-71 - Aircraft.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 48 Federal Acquisition Regulations System 3 2014-10-01 2014-10-01 false Aircraft. 246.408-71..., DEPARTMENT OF DEFENSE CONTRACT MANAGEMENT QUALITY ASSURANCE Government Contract Quality Assurance 246.408-71 Aircraft. (a) The Federal Aviation Administration (FAA) has certain responsibilities and prerogatives...

  2. 48 CFR 246.408-71 - Aircraft.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 48 Federal Acquisition Regulations System 3 2012-10-01 2012-10-01 false Aircraft. 246.408-71..., DEPARTMENT OF DEFENSE CONTRACT MANAGEMENT QUALITY ASSURANCE Government Contract Quality Assurance 246.408-71 Aircraft. (a) The Federal Aviation Administration (FAA) has certain responsibilities and prerogatives...

  3. 48 CFR 246.408-71 - Aircraft.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 48 Federal Acquisition Regulations System 3 2010-10-01 2010-10-01 false Aircraft. 246.408-71..., DEPARTMENT OF DEFENSE CONTRACT MANAGEMENT QUALITY ASSURANCE Government Contract Quality Assurance 246.408-71 Aircraft. (a) The Federal Aviation Administration (FAA) has certain responsibilities and prerogatives...

  4. 48 CFR 246.408-71 - Aircraft.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 48 Federal Acquisition Regulations System 3 2011-10-01 2011-10-01 false Aircraft. 246.408-71..., DEPARTMENT OF DEFENSE CONTRACT MANAGEMENT QUALITY ASSURANCE Government Contract Quality Assurance 246.408-71 Aircraft. (a) The Federal Aviation Administration (FAA) has certain responsibilities and prerogatives...

  5. Handling Pyrophoric Reagents

    SciTech Connect

    Alnajjar, Mikhail S.; Haynie, Todd O.

    2009-08-14

    Pyrophoric reagents are extremely hazardous. Special handling techniques are required to prevent contact with air and the resulting fire. This document provides several methods for working with pyrophoric reagents outside of an inert atmosphere.

  6. Aircraft Maneuvers for the Evaluation of Flying Qualities and Agility. Volume 1. Maneuver Development Process and Initial Maneuver Set

    DTIC Science & Technology

    1993-08-01

    8217 TOLMAX Time of Max Lift Coeff icient QDOAVG Avg Initial Pitch Accol Over 0.25 sec QDO .25SEC Pitch Acceleration at 0.25 sec ODMAX Max Pitch...Qualities Rating Scales," A Thesis Presented for the Master of Science Degree, University of Tennessee, Knoxville, May 1992. 13. Lockenour, J.L

  7. Identification of linearized equations of motion for the fixed wing configuration of the rotor systems research aircraft

    NASA Technical Reports Server (NTRS)

    Balough, D. L.; Sandlin, D. R.

    1986-01-01

    The purpose of this report is to establish linear, decoupled models of rigid body motion for the fixed wing configuration of the Rotor Systems Research Aircraft (RSRA). Longitudinal and lateral control surface fixed linear models were created from aircraft time histories using current system identification techniques. Models were obtained from computer simulation at 160 KCAS and 200 KCAS, and from flight data at 160 KCAS. Comparisons were performed to examine modeling accuracy, variation of dynamics with airspeed and correlation of simulation and flight data results. The results showed that the longitudinal and lateral linear models accurately predicted RSRA dynamics. The flight data results showed that no significant handling qualities problems were present in the RSRA fixed wing aircraft at the flight speed tested.

  8. Practices to identify and preclude adverse Aircraft-and-Rotorcraft-Pilot Couplings - A design perspective

    NASA Astrophysics Data System (ADS)

    Pavel, Marilena D.; Masarati, Pierangelo; Gennaretti, Massimo; Jump, Michael; Zaichik, Larisa; Dang-Vu, Binh; Lu, Linghai; Yilmaz, Deniz; Quaranta, Giuseppe; Ionita, Achim; Serafini, Jacopo

    2015-07-01

    Understanding, predicting and supressing the inadvertent aircraft oscillations caused by Aircraft/Rotorcraft Pilot Couplings (A/RPC) is a challenging problem for designers. These are potential instabilities that arise from the effort of controlling aircraft with high response actuation systems. The present paper reviews, updates and discusses desirable practices to be used during the design process for unmasking A/RPC phenomena. These practices are stemming from the European Commission project ARISTOTEL Aircraft and Rotorcraft Pilot Couplings - Tools and Techniques for Alleviation and Detection (2010-2013) and are mainly related to aerodynamic and structural modelling of the aircraft/rotorcraft, pilot modelling and A/RPC prediction criteria. The paper proposes new methodologies for precluding adverse A/RPCs events taking into account the aeroelasticity of the structure and pilot biodynamic interaction. It is demonstrated that high-frequency accelerations due to structural elasticity cause negative effects on pilot control, since they lead to involuntary body and limb-manipulator system displacements and interfere with pilot's deliberate control activity (biodynamic interaction) and, finally, worsen handling quality ratings.

  9. ERTS-1 Virgin Islands experiment 589: Determine boundaries of ERTS and aircraft data within which useful water quality information can be obtained. [water pollution in St. Thomas harbor, Virgin Islands

    NASA Technical Reports Server (NTRS)

    Coulbourn, W. C.; Egan, W. G.; Olsen, D. A. (Principal Investigator); Heaslip, G. B.

    1973-01-01

    The author has identified the following significant results. The boundaries of application of ERTS-1 and aircraft data are established for St. Thomas harbor within which useful water quality information can be obtained. In situ physical, chemical, and biological water quality and benthic data were collected. Moored current meters were employed. Optical measurements of solar irradiance, color test panel radiance and water absorption were taken. Procedures for correlating in situ optical, biological, and chemical data with underflight aircraft I2S data and ERTS-1 MSS scanner data are presented. Comparison of bulk and precision CCT computer printout data for this application is made, and a simple method for geometrically locating bulk data individual pixels based on land-water interface is described. ERTS spacecraft data and I2S aircraft imagery are correlated with optical in situ measurements of the harbor water, with the aircraft green photographic and ERTS-1 MSS-4 bands being the most useful. The biological pigments correlate inversely with the optical data for inshore areas and directly further seaward. Automated computer data processing facilitated analysis.

  10. Integrated Model Reduction and Control of Aircraft with Flexible Wings

    NASA Technical Reports Server (NTRS)

    Swei, Sean Shan-Min; Zhu, Guoming G.; Nguyen, Nhan T.

    2013-01-01

    This paper presents an integrated approach to the modeling and control of aircraft with exible wings. The coupled aircraft rigid body dynamics with a high-order elastic wing model can be represented in a nite dimensional state-space form. Given a set of desired output covariance, a model reduction process is performed by using the weighted Modal Cost Analysis (MCA). A dynamic output feedback controller, which is designed based on the reduced-order model, is developed by utilizing output covariance constraint (OCC) algorithm, and the resulting OCC design weighting matrix is used for the next iteration of the weighted cost analysis. This controller is then validated for full-order evaluation model to ensure that the aircraft's handling qualities are met and the uttering motion of the wings suppressed. An iterative algorithm is developed in CONDUIT environment to realize the integration of model reduction and controller design. The proposed integrated approach is applied to NASA Generic Transport Model (GTM) for demonstration.

  11. Investigation of the misfueling of reciprocating piston aircraft engines

    NASA Technical Reports Server (NTRS)

    Scott, J. Holland, Jr.

    1988-01-01

    The Aircraft Misfueling Detection Project was developed by the Goddard Space Flight Center/Wallops Flight Facility at Wallops Island, Virginia. Its purpose was to investigate the misfueling of reciprocating piston aircraft engines by the inadvertent introduction of jet fuel in lieu of or as a contaminant of aviation gasoline. The final objective was the development of a device(s) that will satisfactorily detect misfueling and provide pilots with sufficient warning to avoid injury, fatality, or equipment damage. Two devices have been developed and successfully tested: one, a small contamination detection kit, for use by the pilot, and a second, more sensitive, modified gas chromatograph for use by the fixed-base operator. The gas chromatograph, in addition to providing excellent quality control of the fixed-base operator's fuel handling, is a very good backup for the detection kit in the event it produces negative results. Design parameters were developed to the extent that they may be applied easily to commercial production by the aircraft industry.

  12. Reactive uptake coefficients for N2O5 determined from aircraft measurements during the Second Texas Air Quality Study: Comparison to current model parameterizations

    NASA Astrophysics Data System (ADS)

    Brown, Steven S.; Dubé, William P.; Fuchs, Hendrik; Ryerson, Thomas B.; Wollny, Adam G.; Brock, Charles A.; Bahreini, Roya; Middlebrook, Ann M.; Neuman, J. Andrew; Atlas, Elliot; Roberts, James M.; Osthoff, Hans D.; Trainer, Michael; Fehsenfeld, Frederick C.; Ravishankara, A. R.

    2009-04-01

    This paper presents determinations of reactive uptake coefficients for N2O5, γ(N2O5), on aerosols from nighttime aircraft measurements of ozone, nitrogen oxides, and aerosol surface area on the NOAA P-3 during Second Texas Air Quality Study (TexAQS II). Determinations based on both the steady state approximation for NO3 and N2O5 and a plume modeling approach yielded γ(N2O5) substantially smaller than current parameterizations used for atmospheric modeling and generally in the range 0.5-6 × 10-3. Dependence of γ(N2O5) on variables such as relative humidity and aerosol composition was not apparent in the determinations, although there was considerable scatter in the data. Determinations were also inconsistent with current parameterizations of the rate coefficient for homogenous hydrolysis of N2O5 by water vapor, which may be as much as a factor of 10 too large. Nocturnal halogen activation via conversion of N2O5 to ClNO2 on chloride aerosol was not determinable from these data, although limits based on laboratory parameterizations and maximum nonrefractory aerosol chloride content showed that this chemistry could have been comparable to direct production of HNO3 in some cases.

  13. SPAR data handling utilities

    NASA Technical Reports Server (NTRS)

    Giles, G. L.; Haftka, R. T.

    1978-01-01

    The SPAR computer software system is a collection of processors that perform particular steps in the finite-element structural analysis procedure. The data generated by each processor are stored on a data base complex residing on an auxiliary storage device, and these data are then used by subsequent processors. The SPAR data handling utilities use routines to transfer data between the processors and the data base complex. A detailed description of the data base complex organization is presented. A discussion of how these SPAR data handling utilities are used in an application program to perform desired user functions is given with the steps necessary to convert an existing program to a SPAR processor by incorporating these utilities. Finally, a sample SPAR processor is included to illustrate the use of the data handling utilities.

  14. Aircraft cybernetics

    NASA Technical Reports Server (NTRS)

    1977-01-01

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

  15. A comparison of original aircraft MSS and generated surface water reflectance images as predictors of lake water quality indicators

    SciTech Connect

    Ramsey, E.W. III; Jensen, J.R.

    1988-01-01

    Generated reflectance and original MSS images were compared at six blue to near infrared wavelengths at thirty-eight (38) field locations in three different lakes. Both sets of images were evaluated in terms of their importance in explaining the variance of measured reflectances. Subsequently, the generated reflectance images were related to measured chlorophyll /und a/ and total suspended solids using a statistical analysis that uncovered the simplest relationships explaining the greatest amount of each water variables variance. Applying this methodology resulted in predictor equations explaining 82% of the chlorophyll /und a/ variance and 92% of the total suspended solids variance within the thirty-two (32) water samples analyzed. Maps were produced of L Lake depicting the distributions of two water quality indicators: chlorophyll a and total suspended particles. 16 refs., 6 figs., 4 tabs.

  16. A simulation study of the flight dynamics of elastic aircraft. Volume 2: Data

    NASA Technical Reports Server (NTRS)

    Waszak, Martin R.; Davidson, John B.; Schmidt, David K.

    1987-01-01

    The simulation experiment described addresses the effects of structural flexibility on the dynamic characteristics of a generic family of aircraft. The simulation was performed using the NASA Langley VMS simulation facility. The vehicle models were obtained as part of this research project. The simulation results include complete response data and subjective pilot ratings and comments and so allow a variety of analyses. The subjective ratings and analysis of the time histories indicate that increased flexibility can lead to increased tracking errors, degraded handling qualities, and changes in the frequency content of the pilot inputs. These results, furthermore, are significantly affected by the visual cues available to the pilot.

  17. A simulation study of the flight dynamics of elastic aircraft. Volume 1: Experiment, results and analysis

    NASA Technical Reports Server (NTRS)

    Waszak, Martin R.; Davidson, John B.; Schmidt, David K.

    1987-01-01

    The simulation experiment described addresses the effects of structural flexibility on the dynamic characteristics of a generic family of aircraft. The simulation was performed using the NASA Langley VMS simulation facility. The vehicle models were obtained as part of this research. The simulation results include complete response data and subjective pilot ratings and comments and so allow a variety of analyses. The subjective ratings and analysis of the time histories indicate that increased flexibility can lead to increased tracking errors, degraded handling qualities, and changes in the frequency content of the pilot inputs. These results, furthermore, are significantly affected by the visual cues available to the pilot.

  18. Grain Grading and Handling.

    ERIC Educational Resources Information Center

    Rendleman, Matt; Legacy, James

    This publication provides an introduction to grain grading and handling for adult students in vocational and technical education programs. Organized in five chapters, the booklet provides a brief overview of the jobs performed at a grain elevator and of the techniques used to grade grain. The first chapter introduces the grain industry and…

  19. Microforms in Information Handling.

    ERIC Educational Resources Information Center

    Williams, B. J. S.

    In an attempt to identify some of the factors which influence the utility of microforms as a medium for information handling, this report first traces some of the landmarks in the evolution of microforms since their invention in 1893. It next provides a factual account of current microform media and formats. The last section of the report contains…

  20. Case-based approach to handling aircraft malfunctions

    NASA Astrophysics Data System (ADS)

    Karamouzis, Stamos T.; Feyock, Stefan

    1993-03-01

    Reasoning about physical systems in operation is a difficult task, and any attempt to automate the process must overcome the problems of modeling normal behavior, diagnosing faults, and predicting future behavior. This paper describes a prototypical case-based reasoner (CBR) that operates in the domain of in-flight fault diagnosis and prognosis of aviation subsystems, particularly jet engines. The reasoner operates on the observation that the ability of a CBR program to reason about physical systems can be significantly enhanced by the addition to the CBR program of a model of the physical system to describe the system's structural, functional, and causal behavior.

  1. 7 CFR 996.40 - Handling standards.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 7 Agriculture 8 2011-01-01 2011-01-01 false Handling standards. 996.40 Section 996.40 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Marketing Agreements and Orders; Fruits, Vegetables, Nuts), DEPARTMENT OF AGRICULTURE MINIMUM QUALITY AND...

  2. Flight Test Results on the Stability and Control of the F-15B Quiet Spike Aircraft

    NASA Technical Reports Server (NTRS)

    Moua, Cheng; McWherter, Shaun H.; Cox, Timothy H.; Gera, Joseph

    2007-01-01

    The Quiet Spike (QS) flight research program was an aerodynamic and structural proof-of-concept of a telescoping sonic-boom suppressing nose boom on an F-15 B aircraft. The program goal was to collect flight data for model validation up to 1.8 Mach. The primary test philosophy was maintaining safety of flight. In the area of stability and controls the primary concerns were to assess the potential destabilizing effect of the spike on the stability, controllability, and handling qualities of the aircraft and to ensure adequate stability margins across the entire QS flight envelop. This paper reports on the stability and control methods used for flight envelope clearance and flight test results of the F-15B Quiet Spike. Also discussed are the flight test approach, the criteria to proceed to the next flight condition, brief pilot commentary on typical piloting tasks, approach and landing, and refueling task, and air data sensitivity to the flight control system.

  3. A Theory for the Roll-Ratchet Phenomenon in High Performance Aircraft

    NASA Technical Reports Server (NTRS)

    Hess, Ronald A.

    1997-01-01

    Roll-ratchet refers to a high frequency oscillation which can occur in pilot-in-the-loop control of roll attitude in high performance aircraft. The frequencies of oscillation are typically well beyond those associated with the more familiar pilot-induced oscillation. A structural model of the human pilot which has been employed to provide a unified theory for aircraft handling qualities and pilot-induced oscillations is employed here to provide a theory for the existence of roll-ratchet. It is hypothesized and demonstrated using the structural model that the pilot's inappropriate use of vestibular acceleration feedback can cause this phenomenon, a possibility which has been discussed previously by other researchers. The possible influence of biodynamic feedback on roll ratchet is also discussed.

  4. Advanced AFCS developments on the XV-15 tilt rotor research aircraft. [Automatic Flight Control System

    NASA Technical Reports Server (NTRS)

    Churchill, G. B.; Gerdes, R. M.

    1984-01-01

    The design criteria and control and handling qualities of the Automatic Flight Control System (AFCS), developed in the framework of the XV-15 tilt-rotor research aircraft, are evaluated, differentiating between the stability and control criteria. A technically aggressive SCAS control law was implemented, demonstrating that significant benefits accrue when stability criteria are separated from design criteria; the design analyses for application of the control law are presented, and the limit bandwidth for stabilization in hovering flight is shown to be defined by rotor or control lag functions. Flight tests of the aircraft resulted in a rating of 3 on the Cooper-Harper scale; a possibility of achieving a rating of 2 is expected if the system is applied to the yaw and heave control modes.

  5. Digital adaptive model following flight control. [using fighter aircraft mathematical model-following algorithm

    NASA Technical Reports Server (NTRS)

    Alag, G. S.; Kaufman, H.

    1974-01-01

    Simple mechanical linkages are often unable to cope with the many control problems associated with high performance aircraft maneuvering over a wide flight envelope. One procedure for retaining uniform handling qualities over such an envelope is to implement a digital adaptive controller. Towards such an implementation an explicit adaptive controller, which makes direct use of online parameter identification, has been developed and applied to the linearized equations of motion for a typical fighter aircraft. The system is composed of an online weighted least squares identifier, a Kalman state filter, and a single stage real model following control law. The corresponding control gains are readily adjustable in accordance with parameter changes to ensure asymptotic stability if the conditions for perfect model following are satisfied and stability in the sense of boundedness otherwise.

  6. Aircrew-aircraft integration: A summary of US Army research programs and plans

    NASA Technical Reports Server (NTRS)

    Key, D. L.; Aiken, E. W.

    1984-01-01

    A review of selected programs which illustrate the research efforts of the U.S. Army Aeromechanics Laboratory in the area of aircrew-aircraft integration is presented. Plans for research programs to support the development of future military rotorcraft are also described. The crew of a combat helicopter must, in general, perform two major functions during the conduct of a particular mission: flightpath control and mission management. Accordingly, the research programs described are being conducted in the same two major categories: (1) flightpath control, which encompasses the areas of handling qualities, stability and control, and displays for the pilot's control of the rotorcraft's flightpath, and (2) mission management, which includes human factors and cockpit integration research topics related to performance of navigation, communication, and aircraft systems management tasks.

  7. Aircraft Corrosion

    DTIC Science & Technology

    1981-08-01

    chlore mais dans une proportion semblable b cells d’une eau de vil)e ; - lea solides, d’aprbs lea analyses chimique et criatallographique, paraissaiont...IATA member airlines at $100 million based on 1976 operations. Thus the numbers are large, but detailed analyses on specific aircraft types, in known...demonstrate this in any quantitative way with accurate figures. Better information is required on the cost of corrosion, together with analyses of the

  8. Aircraft Ducting

    NASA Technical Reports Server (NTRS)

    1996-01-01

    Templeman Industries developed the Ultra-Seal Ducting System, an environmental composite air duct with a 50 percent weight savings over current metallic ducting, but could not find a commercial facility with the ability to test it. Marshall Space Flight Center conducted a structural evaluation of the duct, equivalent to 86 years of take-offs and landings in an aircraft. Boeing Commercial Airplane Group and McDonnell Douglas Corporation are currently using the ducts.

  9. Environmental protection agency aircraft emissions standards

    NASA Technical Reports Server (NTRS)

    Kittredge, G. D.

    1977-01-01

    Emissions of air pollutants from aircraft were investigated in order to determine: (1) the extent to which such emissions affect air quality in air quality control regions throughout the United States; and (2) the technological feasibility of controlling such emissions. The basic information supporting the need for aircraft emissions standards is summarized. The EPA ambient air quality standards are presented. Only the primary (health related) standards are shown. Of the six pollutants, only the first three, carbon monoxide (CO), hydrocarbons (HC), and nitrogen oxides, are influenced significantly by aircraft.

  10. Development of an advanced pitch active control system and a reduced area horizontal tail for a wide-body jet aircraft

    NASA Technical Reports Server (NTRS)

    Guinn, Wiley A.

    1984-01-01

    The development of an advanced pitch active control system (PACS) and a reduced area horizontal tail for a wide-body jet transport (L-1011) with a flying horizontal stabilizer is discussed. The advanced PACS control law design objectives were to provide satisfactory handling qualities for aft c.g. flight conditions to negative static stability margins of 10 percent and to provide good maneuver control column force gradients for nonlinear stability flight conditions. Validity of the control laws were demonstrated by piloted flight simulation tests on the NASA Langley Visual Motion Simulator. Satisfactory handling qualities were actually demonstrated to a negative 20 percent static stability margin. The PACS control laws were mechanized to provide the system architecture that would be suitable for an L-1011 flight test program to a negative stability margin of 3 percent which represents the aft c.g. limits of the aircraft. Reduced area horizontal tail designs of 30 and 38 percent with respect to the L-1011 standard tail were designed, fabricated and wind tunnel tested. Drag reductions and weight savings of the 30 percent smaller tail would provide an L/D benefit of about 2% and the 38% small tail L/D benefit would be about 3 percent. However, forward c.g. limitations would have to be imposed on the aircraft because the maximum horizontal tail lift goal was not achieved and sufficient aircraft nose-up control authority was not available. This limitation would not be required for a properly designed new aircraft.

  11. Solid waste handling

    SciTech Connect

    Parazin, R.J.

    1995-05-31

    This study presents estimates of the solid radioactive waste quantities that will be generated in the Separations, Low-Level Waste Vitrification and High-Level Waste Vitrification facilities, collectively called the Tank Waste Remediation System Treatment Complex, over the life of these facilities. This study then considers previous estimates from other 200 Area generators and compares alternative methods of handling (segregation, packaging, assaying, shipping, etc.).

  12. Renal phosphate handling: Physiology

    PubMed Central

    Prasad, Narayan; Bhadauria, Dharmendra

    2013-01-01

    Phosphorus is a common anion. It plays an important role in energy generation. Renal phosphate handling is regulated by three organs parathyroid, kidney and bone through feedback loops. These counter regulatory loops also regulate intestinal absorption and thus maintain serum phosphorus concentration in physiologic range. The parathyroid hormone, vitamin D, Fibrogenic growth factor 23 (FGF23) and klotho coreceptor are the key regulators of phosphorus balance in body. PMID:23961477

  13. Uranium hexafluoride handling. Proceedings

    SciTech Connect

    Not Available

    1991-12-31

    The United States Department of Energy, Oak Ridge Field Office, and Martin Marietta Energy Systems, Inc., are co-sponsoring this Second International Conference on Uranium Hexafluoride Handling. The conference is offered as a forum for the exchange of information and concepts regarding the technical and regulatory issues and the safety aspects which relate to the handling of uranium hexafluoride. Through the papers presented here, we attempt not only to share technological advances and lessons learned, but also to demonstrate that we are concerned about the health and safety of our workers and the public, and are good stewards of the environment in which we all work and live. These proceedings are a compilation of the work of many experts in that phase of world-wide industry which comprises the nuclear fuel cycle. Their experience spans the entire range over which uranium hexafluoride is involved in the fuel cycle, from the production of UF{sub 6} from the naturally-occurring oxide to its re-conversion to oxide for reactor fuels. The papers furnish insights into the chemical, physical, and nuclear properties of uranium hexafluoride as they influence its transport, storage, and the design and operation of plant-scale facilities for production, processing, and conversion to oxide. The papers demonstrate, in an industry often cited for its excellent safety record, continuing efforts to further improve safety in all areas of handling uranium hexafluoride. Selected papers were processed separately for inclusion in the Energy Science and Technology Database.

  14. Linear tracking systems with applications to aircraft control system design

    NASA Technical Reports Server (NTRS)

    Lee, W. H.; Athans, M.; Castanon, D.; Bacchioloni, F.

    1977-01-01

    A class of optimal linear time invariant tracking systems, both in continuous time and discrete time, of which the number of inputs (which are restricted to be step functions) is equal to the number of system outputs, is studied. Along with derivation of equations and design procedures, two discretization schemes are presented, constraining either the control or its time derivative, to be a constant over each sampling period. Descriptions are given for the linearized model of the F-8C aircraft longitudinal dynamics, and the C* handling qualities criterion, which then serve as an illustration of the applications of these linear tracking designs. A suboptimal reduced state design is also presented. Numerical results are given for both the continuous time and discrete time designs.

  15. Simulation of the XV-15 tilt rotor research aircraft

    NASA Technical Reports Server (NTRS)

    Churchill, G. B.; Dugan, D. C.

    1982-01-01

    The effective use of simulation from issuance of the request for proposal through conduct of a flight test program for the XV-15 Tilt Rotor Research Aircraft is discussed. From program inception, simulation complemented all phases of XV-15 development. The initial simulation evaluations during the source evaluation board proceedings contributed significantly to performance and stability and control evaluations. Eight subsequent simulation periods provided major contributions in the areas of control concepts; cockpit configuration; handling qualities; pilot workload; failure effects and recovery procedures; and flight boundary problems and recovery procedures. The fidelity of the simulation also made it a valuable pilot training aid, as well as a suitable tool for military and civil mission evaluations. Simulation also provided valuable design data for refinement of automatic flight control systems. Throughout the program, fidelity was a prime issue and resulted in unique data and methods for fidelity evaluation which are presented and discussed.

  16. Recommendations for cask features for robotic handling from the Advanced Handling Technology Project

    SciTech Connect

    Drotning, W.

    1991-02-01

    This report describes the current status and recent progress in the Advanced Handling Technology Project (AHTP) initiated to explore the use of advanced robotic systems and handling technologies to perform automated cask handling operations at radioactive waste handling facilities, and to provide guidance to cask designers on the impact of robotic handling on cask design. Current AHTP tasks have developed system mock-ups to investigate robotic manipulation of impact limiters and cask tiedowns. In addition, cask uprighting and transport, using computer control of a bridge crane and robot, were performed to demonstrate the high speed cask transport operation possible under computer control. All of the current AHTP tasks involving manipulation of impact limiters and tiedowns require robotic operations using a torque wrench. To perform these operations, a pneumatic torque wrench and control system were integrated into the tool suite and control architecture of the gantry robot. The use of captured fasteners is briefly discussed as an area where alternative cask design preferences have resulted from the influence of guidance for robotic handling vs traditional operations experience. Specific robotic handling experiences with these system mock-ups highlight a number of continually recurring design principles: (1) robotic handling feasibility is improved by mechanical designs which emphasize operation with limited dexterity in constrained workspaces; (2) clearances, tolerances, and chamfers must allow for operations under actual conditions with consideration for misalignment and imprecise fixturing; (3) successful robotic handling is enhanced by including design detail in representations for model-based control; (4) robotic handling and overall quality assurance are improved by designs which eliminate the use of loose, disassembled parts. 8 refs., 15 figs.

  17. Educating with Aircraft Models

    ERIC Educational Resources Information Center

    Steele, Hobie

    1976-01-01

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

  18. XV-15 Tiltrotor Aircraft: 1999 Acoustic Testing - Test Report

    NASA Technical Reports Server (NTRS)

    Edwards, Bryan D.; Conner, David A.

    2003-01-01

    An XV-15 acoustic test is discussed, and measured results are presented. The test was conducted by NASA Langley and Bell Helicopter Textron, Inc., during October 1999, at the BHTI test site near Waxahachie, Texas. As part of the NASA-sponsored Short Haul Civil Tiltrotor noise reduction initiative, this was the third in a series of three major XV-15 acoustic tests. Their purpose was to document the acoustic signature of the XV-15 tiltrotor aircraft for a variety of flight conditions and to minimize the noise signature during approach. Tradeoffs between flight procedures and the measured noise are presented to illustrate the noise abatement flight procedures. The test objectives were to support operation of future tiltrotors by further developing and demonstrating low-noise flight profiles, while maintaining acceptable handling and ride qualities, and refine approach profiles, selected from previous (1995 & 1997) tiltrotor testing, to incorporate Instrument Flight Rules (IFR), handling qualities constraints, operations and tradeoffs with sound. Primary emphasis was given to the approach flight conditions where blade-vortex interaction (BVI) noise dominates, because this condition influences community noise impact more than any other. An understanding of this part of the noise generating process could guide the development of low noise flight operations and increase the tiltrotor's acceptance in the community.

  19. Aircraft Fault Detection and Classification Using Multi-Level Immune Learning Detection

    NASA Technical Reports Server (NTRS)

    Wong, Derek; Poll, Scott; KrishnaKumar, Kalmanje

    2005-01-01

    This work is an extension of a recently developed software tool called MILD (Multi-level Immune Learning Detection), which implements a negative selection algorithm for anomaly and fault detection that is inspired by the human immune system. The immunity-based approach can detect a broad spectrum of known and unforeseen faults. We extend MILD by applying a neural network classifier to identify the pattern of fault detectors that are activated during fault detection. Consequently, MILD now performs fault detection and identification of the system under investigation. This paper describes the application of MILD to detect and classify faults of a generic transport aircraft augmented with an intelligent flight controller. The intelligent control architecture is designed to accommodate faults without the need to explicitly identify them. Adding knowledge about the existence and type of a fault will improve the handling qualities of a degraded aircraft and impact tactical and strategic maneuvering decisions. In addition, providing fault information to the pilot is important for maintaining situational awareness so that he can avoid performing an action that might lead to unexpected behavior - e.g., an action that exceeds the remaining control authority of the damaged aircraft. We discuss the detection and classification results of simulated failures of the aircraft's control system and show that MILD is effective at determining the problem with low false alarm and misclassification rates.

  20. 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.

  1. Complying with US and European complaint handling requirements.

    PubMed

    Donawa, M E

    1997-09-01

    The importance of customer complaints for providing valuable information on the use of medical devices is clearly reflected in United States (US) and European quality system requirements for handling complaints. However, there are significant differences in US and European complaint handling requirements. This article will discuss those differences and methods for ensuring compliance.

  2. 10 CFR 71.127 - Handling, storage, and shipping control.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 10 Energy 2 2014-01-01 2014-01-01 false Handling, storage, and shipping control. 71.127 Section 71.127 Energy NUCLEAR REGULATORY COMMISSION (CONTINUED) PACKAGING AND TRANSPORTATION OF RADIOACTIVE MATERIAL Quality Assurance § 71.127 Handling, storage, and shipping control. The licensee,...

  3. 10 CFR 71.127 - Handling, storage, and shipping control.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 10 Energy 2 2011-01-01 2011-01-01 false Handling, storage, and shipping control. 71.127 Section 71.127 Energy NUCLEAR REGULATORY COMMISSION (CONTINUED) PACKAGING AND TRANSPORTATION OF RADIOACTIVE MATERIAL Quality Assurance § 71.127 Handling, storage, and shipping control. The licensee,...

  4. 10 CFR 71.127 - Handling, storage, and shipping control.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 10 Energy 2 2013-01-01 2013-01-01 false Handling, storage, and shipping control. 71.127 Section 71.127 Energy NUCLEAR REGULATORY COMMISSION (CONTINUED) PACKAGING AND TRANSPORTATION OF RADIOACTIVE MATERIAL Quality Assurance § 71.127 Handling, storage, and shipping control. The licensee,...

  5. 10 CFR 71.127 - Handling, storage, and shipping control.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 10 Energy 2 2012-01-01 2012-01-01 false Handling, storage, and shipping control. 71.127 Section 71.127 Energy NUCLEAR REGULATORY COMMISSION (CONTINUED) PACKAGING AND TRANSPORTATION OF RADIOACTIVE MATERIAL Quality Assurance § 71.127 Handling, storage, and shipping control. The licensee,...

  6. 10 CFR 71.127 - Handling, storage, and shipping control.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 10 Energy 2 2010-01-01 2010-01-01 false Handling, storage, and shipping control. 71.127 Section 71.127 Energy NUCLEAR REGULATORY COMMISSION (CONTINUED) PACKAGING AND TRANSPORTATION OF RADIOACTIVE MATERIAL Quality Assurance § 71.127 Handling, storage, and shipping control. The licensee,...

  7. Standardizing the Handling of Surgical Specimens.

    PubMed

    Shirey, Cheryl; Perrego, Kristen

    2015-11-01

    To standardize the handling of surgical specimens, the OR clinical educators in a community hospital setting devised a series of departmental changes as a quality improvement project. A newly created skill validation was reviewed in an hour-long educational meeting with all OR staff members. In addition to creating a new annual skill validation, discussions about specimens were included in the hand over, the time out, and a newly instituted debriefing tool to be used toward the end of a procedure. This interdisciplinary group devised interventions to improve the process of handling specimens such as standardizing the labeling process and changing the transparency of the specimen container. The goal was to assure standardization of specimen handling, specifically to assist novice staff members, and to harmonize inconsistencies between specialties within the practice of existing staff members. These combined methods helped to ensure accurate communication and procurement of specimens for all procedures.

  8. Solid handling valve

    DOEpatents

    Williams, William R.

    1979-01-01

    The present invention is directed to a solids handling valve for use in combination with lock hoppers utilized for conveying pulverized coal to a coal gasifier. The valve comprises a fluid-actuated flow control piston disposed within a housing and provided with a tapered primary seal having a recessed seat on the housing and a radially expandable fluid-actuated secondary seal. The valve seals are highly resistive to corrosion, erosion and abrasion by the solids, liquids, and gases associated with the gasification process so as to minimize valve failure.

  9. Students' Strategies for Exception Handling

    ERIC Educational Resources Information Center

    Rashkovits, Rami; Lavy, Ilana

    2011-01-01

    This study discusses and presents various strategies employed by novice programmers concerning exception handling. The main contributions of this paper are as follows: we provide an analysis tool to measure the level of assimilation of exception handling mechanism; we present and analyse strategies to handle exceptions; we present and analyse…

  10. Pilot evaluation of sailplane handling qualities

    NASA Technical Reports Server (NTRS)

    Bennett, A. G., Jr.

    1978-01-01

    The evaluation sailplanes were found generally deficient in the area of cockpit layout. The pilots indicated general dissatisfaction with high pitch sensitivity especially when coupled with inertially induced stick forces. While all sailplanes were judged satisfactory for centering thermals and in the ease of speed control in circling flight, pilot opinions diverged on the maneuvering response, pull-out characteristics from a dive, and on phugoid damping. Lateral-directional control problems were noted mainly during takeoff and landing for most sailplanes with the landing wheel ahead of center of gravity. Pilot opinion of in-flight lateral-directional stability and control was generally satisfactory. Five of the evaluation sailplanes exhibited a very narrow airspeed band in which perceptible stall warning buffet occurred. However, this characteristic was considered not objectionable when stall recovery was easy. The pilots objected to the characteristics of a wide airspeed band of stall warning followed by a stall with yawing and rolling tendency and substantial loss of altitude during the stall. Glide path control for the evaluation sailplanes was found to be generally objectionable.

  11. 41 CFR 102-36.345 - May we dispose of excess Flight Safety Critical Aircraft Parts (FSCAP)?

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... Flight Safety Critical Aircraft Parts (FSCAP)? 102-36.345 Section 102-36.345 Public Contracts and... Requires Special Handling Aircraft and Aircraft Parts § 102-36.345 May we dispose of excess Flight Safety... appropriate Criticality Code on the SF 120, and ensure that all available historical and maintenance...

  12. 41 CFR 102-36.345 - May we dispose of excess Flight Safety Critical Aircraft Parts (FSCAP)?

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... Flight Safety Critical Aircraft Parts (FSCAP)? 102-36.345 Section 102-36.345 Public Contracts and... Requires Special Handling Aircraft and Aircraft Parts § 102-36.345 May we dispose of excess Flight Safety... appropriate Criticality Code on the SF 120, and ensure that all available historical and maintenance...

  13. 41 CFR 102-36.345 - May we dispose of excess Flight Safety Critical Aircraft Parts (FSCAP)?

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... Flight Safety Critical Aircraft Parts (FSCAP)? 102-36.345 Section 102-36.345 Public Contracts and... Requires Special Handling Aircraft and Aircraft Parts § 102-36.345 May we dispose of excess Flight Safety... appropriate Criticality Code on the SF 120, and ensure that all available historical and maintenance...

  14. 41 CFR 102-36.345 - May we dispose of excess Flight Safety Critical Aircraft Parts (FSCAP)?

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... Flight Safety Critical Aircraft Parts (FSCAP)? 102-36.345 Section 102-36.345 Public Contracts and... Requires Special Handling Aircraft and Aircraft Parts § 102-36.345 May we dispose of excess Flight Safety... appropriate Criticality Code on the SF 120, and ensure that all available historical and maintenance...

  15. Improved portable lighting for visual aircraft inspection

    SciTech Connect

    Shagam, R.N.; Lerner, J.; Shie, R.

    1995-04-01

    The most common tool used by aircraft inspectors is the personal flashlight. While it is compact and very portable, it is generally typified by poor beam quality which can interfere with the ability for an inspector to detect small defects and anomalies, such as cracks and corrosion sites, which may be indicators of major structural problems. A Light Shaping Diffuser{trademark} (LSD) installed in a stock flashlight as a replacement to the lens can improve the uniformity of an average flashlight and improve the quality of the inspection. Field trials at aircraft maintenance facilities have demonstrated general acceptance of the LSD by aircraft inspection and maintenance personnel.

  16. Aircraft design optimization with multidisciplinary performance criteria

    NASA Technical Reports Server (NTRS)

    Morris, Stephen; Kroo, Ilan

    1989-01-01

    The method described here for aircraft design optimization with dynamic response considerations provides an inexpensive means of integrating dynamics into aircraft preliminary design. By defining a dynamic performance index that can be added to a conventional objective function, a designer can investigate the trade-off between performance and handling (as measured by the vehicle's unforced response). The procedure is formulated to permit the use of control system gains as design variables, but does not require full-state feedback. The examples discussed here show how such an approach can lead to significant improvements in the design as compared with the more common sequential design of system and control law.

  17. Bulk material handling system

    DOEpatents

    Kleysteuber, William K.; Mayercheck, William D.

    1979-01-01

    This disclosure relates to a bulk material handling system particularly adapted for underground mining and includes a monorail supported overhead and carrying a plurality of conveyors each having input and output end portions with the output end portion of a first of the conveyors positioned above an input end portion of a second of the conveyors, a device for imparting motion to the conveyors to move the material from the input end portions toward the output end portions thereof, a device for supporting at least one of the input and output end portions of the first and second conveyors from the monorail, and the supporting device including a plurality of trolleys rollingly supported by the monorail whereby the conveyors can be readily moved therealong.

  18. Aircraft Electric Secondary Power

    NASA Technical Reports Server (NTRS)

    1983-01-01

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

  19. Platelets: handle with care.

    PubMed

    Thomas, S

    2016-10-01

    Platelets are delicate cells that require careful handling between collection, preparation and transfusion. This review addresses practical questions relating to platelet concentration, resting time after collection, total time and number of periods without agitation and temperature. The bags in which platelets are stored are made from gas-permeable plastic to allow sufficient oxygen for the platelets to maintain aerobic respiration. Manufacturers have assigned limits for platelet content and concentration, and these must not be exceeded. There is no strong evidence for or against the resting of platelets post-collection and pre-agitation, but platelets should not be over-wrapped during this period as this compromises gas exchange; a short rest period of up to 1 h may allow the separation of minor aggregates. It is necessary to transport platelet concentrates (e.g. from manufacturing site to hospital), but these periods without gas exchange must be limited to avoid excessive damage to the platelets. Current data support a total of 24 h of transportation per component but with no individual period lasting more than 8 h. Platelets need to be stored at 20-24 °C based on evidence that colder storage leads to irreversible changes on the platelet membrane, resulting in phagocytosis of the platelets following transfusion. Storage at warmer temperatures may lead to an increase in bacterial risk. On the basis of this review, the UK Guidelines for Blood Transfusion Services have been updated to ensure that platelets are handled in the most appropriate way to ensure that efficacious components are provided for patients.

  20. Application of nonlinear adaptive motion washout to transport ground-handling simulation

    NASA Technical Reports Server (NTRS)

    Parrish, R. V.; Martin, D. J., Jr.

    1983-01-01

    The application of a nonlinear coordinated adaptive motion washout to the transport ground-handling environment is documented. Additions to both the aircraft math model and the motion washout system are discussed. The additions to the simulated-aircraft math model provided improved modeling fidelity for braking and reverse-thrust application, and the additions to the motion-base washout system allowed transition from the desired flight parameters to the less restrictive ground parameters of the washout.

  1. Piloted simulation study of an ILS approach of a twin-pusher business/commuter turboprop aircraft configuration

    NASA Technical Reports Server (NTRS)

    Riley, Donald R.; Brandon, Jay M.; Glaab, Louis J.

    1994-01-01

    A six-degree-of-freedom nonlinear simulation of a twin-pusher, turboprop business/commuter aircraft configuration representative of the Cessna ATPTB (Advanced turboprop test bed) was developed for use in piloted studies with the Langley General Aviation Simulator. The math models developed are provided, simulation predictions are compared with with Cessna flight-test data for validation purposes, and results of a handling quality study during simulated ILS (instrument landing system) approaches and missed approaches are presented. Simulated flight trajectories, task performance measures, and pilot evaluations are presented for the ILS approach and missed-approach tasks conducted with the vehicle in the presence of moderate turbulence, varying horizontal winds and engine-out conditions. Six test subjects consisting of two research pilots, a Cessna test pilot, and three general aviation pilots participated in the study. This effort was undertaken in cooperation with the Cessna Aircraft Company.

  2. Pilot Preferences on Displayed Aircraft Control Variables

    NASA Technical Reports Server (NTRS)

    Trujillo, Anna C.; Gregory, Irene M.

    2013-01-01

    The experiments described here explored how pilots want available maneuver authority information transmitted and how this information affects pilots before and after an aircraft failure. The aircraft dynamic variables relative to flight performance were narrowed to energy management variables. A survey was conducted to determine what these variables should be. Survey results indicated that bank angle, vertical velocity, and airspeed were the preferred variables. Based on this, two displays were designed to inform the pilot of available maneuver envelope expressed as bank angle, vertical velocity, and airspeed. These displays were used in an experiment involving control surface failures. Results indicate the displayed limitations in bank angle, vertical velocity, and airspeed were helpful to the pilots during aircraft surface failures. However, the additional information did lead to a slight increase in workload, a small decrease in perceived aircraft flying qualities, and no effect on aircraft situation awareness.

  3. REMOTE HANDLING ARRANGEMENTS

    DOEpatents

    Ginns, D.W.

    1958-04-01

    A means for handling remotely a sample pellet to be irradiated in a nuclear reactor is proposed. It is comprised essentially of an inlet tube extending through the outer shield of the reactor and being inclined so that its outer end is at a higher elevation than its inner end, an outlet tube extending through the outer shield being inclined so that its inner end is at a higher elevation than its outer end, the inner ends of these two tubes being interconnected, and a straight tube extending through the outer shield and into the reactor core between the inlet and outlet tubes and passing through the juncture of said inner ends. A rod-like member is rotatably and slidely operated within the central straight tube and has a receptacle on its inner end for receiving a sample pellet from the inlet tube. The rod member is operated to pick up a sample pellet from the inlet tube, carry the sample pellet into the irradiating position within the core, and return to the receiving position where it is rotated to dump the irradiated pellet into the outlet tube by which it is conveyed by gravity to the outside of the reactor. Stop members are provided in the inlet tube, and electrical operating devices are provided to control the sequence of the operation automatically.

  4. Handling the Heat.

    ERIC Educational Resources Information Center

    Caton, Jay

    1991-01-01

    School food-service programs, endangered by rising costs, would benefit by taking the following steps: (1) improve food quality and presentation; (2) renovate the appearance of cafeterias; (3) enlist cafeteria personnel in reforms and include profit sharing; (4) update management procedures; and (5) cut bureaucracy. (MLF)

  5. Propulsion controlled aircraft computer

    NASA Technical Reports Server (NTRS)

    Cogan, Bruce R. (Inventor)

    2010-01-01

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

  6. A methodology for designing aircraft to low sonic boom constraints

    NASA Technical Reports Server (NTRS)

    Mack, Robert J.; Needleman, Kathy E.

    1991-01-01

    A method for designing conceptual supersonic cruise aircraft to meet low sonic boom requirements is outlined and described. The aircraft design is guided through a systematic evolution from initial three view drawing to a final numerical model description, while the designer using the method controls the integration of low sonic boom, high supersonic aerodynamic efficiency, adequate low speed handling, and reasonable structure and materials technologies. Some experience in preliminary aircraft design and in the use of various analytical and numerical codes is required for integrating the volume and lift requirements throughout the design process.

  7. Small Aircraft Transportation System, Higher Volume Operations Concept: Normal Operations

    NASA Technical Reports Server (NTRS)

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

    2004-01-01

    This document defines the Small Aircraft Transportation System (SATS), Higher Volume Operations (HVO) concept for normal conditions. In this concept, a block of airspace would be established around designated non-towered, non-radar airports during periods of poor weather. Within this new airspace, pilots would take responsibility for separation assurance between their aircraft and other similarly equipped aircraft. Using onboard equipment and procedures, they would then approach and land at the airport. Departures would be handled in a similar fashion. The details for this operational concept are provided in this document.

  8. Fluid handling equipment: A compilation

    NASA Technical Reports Server (NTRS)

    1976-01-01

    Devices and techniques used in fluid-handling and vacuum systems are described. Section 1 presents several articles on fluid lines and tubing. Section 2 describes a number of components such as valves, filters, and regulators. The last section contains descriptions of a number of innovative fluid-handling systems.

  9. Using Fly-By-Wire Technology in Future Models of the UH-60 and Other Rotary Wing Aircraft

    NASA Technical Reports Server (NTRS)

    Solem, Courtney K.

    2011-01-01

    Several fixed-winged airplanes have successfully used fly-by-wire (FBW) technology for the last 40 years. This technology is now beginning to be incorporated into rotary wing aircraft. By using FBW technology, manufacturers are expecting to improve upon the weight, maintenance time and costs, handling and reliability of the aircraft. Before mass production of this new system begins in new models such as the UH-60MU, testing must be conducted to insure the safety of this technology as well as to reassure others it will be worth the time and money to make such a dramatic change to a perfectly functional machine. The RASCAL JUH-60A has been modified for these purposes. This Black Hawk helicopter has already been equipped with the FBW technology and can be configured as a near perfect representation of the UH-60MU. Because both machines have very similar qualities, the data collected from the RASCAL can be used to make future decisions about the UH-60MU. The U.S. Army AFDD Flight Project Office oversees all the design modifications for every hardware system used in the RASCAL aircraft. This project deals with specific designs and analyses of unique RASCAL aircraft subsystems and their modifications to conduct flight mechanics research.

  10. Aircraft flight test trajectory control

    NASA Technical Reports Server (NTRS)

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

    1988-01-01

    Two control law design techniques are compared and the performance of the resulting controllers evaluated. The design requirement is for a flight test trajectory controller (FTTC) capable of closed-loop, outer-loop control of an F-15 aircraft performing high-quality research flight test maneuvers. The maneuver modeling, linearization, and design methodologies utilized in this research, are detailed. The results of applying these FTTCs to a nonlinear F-15 simulation are presented.

  11. A guide to forest seed handling

    SciTech Connect

    Willan, R.L.

    1986-01-01

    This guide to forest seed handling focuses on seed quality, i.e., the physiological viability and vigor of the seeds. Seed and fruit development, germination, and dormancy and the fundamentals of planning seed collections are covered. The guide includes discussions on seed collection of fallen fruits or seeds from the forest floor from the crowns of felled trees, and from standing trees with access from the ground and with other means of access. Also considered are precautions to be followed during fruit and seed handling between collection and processing. The different stages in seed processing are detailed, including extraction, depulping, drying, tumbling and threshing, dewinging, cleaning, grading, and mixing. Factors affecting seed longevity in storage and the choice of storage methods are reviewed. Different forms of seed pretreatment and seed testing methods are described.

  12. A Pilot Opinion Study of Lateral Control Requirements for Fighter-Type Aircraft

    NASA Technical Reports Server (NTRS)

    Creer, Brent Y.; Stewart, John D.; Merrick, Robert B.; Drinkwater, Fred J., III

    1959-01-01

    As part of a continuing NASA program of research on airplane handling qualities, a pilot opinion investigation has been made on the lateral control requirements of fighter aircraft flying in their combat speed range. The investigation was carried out using a stationary flight simulator and a moving flight simulator, and the flight simulator results were supplemented by research tests in actual flight. The flight simulator study was based on the presumption that the pilot rates the roll control of an airplane primarily on a single-degree-of-freedom basis; that is, control of angle of roll about the aircraft body axis being of first importance. From the assumption of a single degree of freedom system it follows that there are two fundamental parameters which govern the airplane roll response, namely the roll damping expressed as a time constant and roll control power in terms of roll acceleration. The simulator study resulted in a criterion in terms of these two parameters which defines satisfactory, unsatisfactory, and unacceptable roll performance from a pilot opinion standpoint. The moving simulator results were substantiated by the in-flight investigation. The derived criterion was compared with the roll performance criterion based upon wing tip helix angle and also with other roll performance concepts which currently influence the roll performance design of military fighter aircraft flying in their combat speed range.

  13. Unmanned aircraft systems

    Technology Transfer Automated Retrieval System (TEKTRAN)

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

  14. Information Handling is the Problem

    NASA Technical Reports Server (NTRS)

    Malin, Jane T.

    2001-01-01

    This slide presentation reviews the concerns surrounding the automation of information handling. There are two types of decision support software that supports most Space Station Flight Controllers. one is very simple, and the other is very complex. A middle ground is sought. This is the reason for the Human Centered Autonomous and Assistant Systems Testbed (HCAAST) Project. The aim is to study flight controllers at work, and in the bigger picture, with particular attention to how they handle information and how coordination of multiple teams is performed. The focus of the project is on intelligent assistants to assist in handling information for the flight controllers.

  15. HAND TRUCK FOR HANDLING EQUIPMENT

    DOEpatents

    King, D.W.

    1959-02-24

    A truck is described for the handling of large and relatively heavy pieces of equipment and particularly for the handling of ion source units for use in calutrons. The truck includes a chassis and a frame pivoted to the chassis so as to be operable to swing in the manner of a boom. The frame has spaced members so arranged that the device to be handled can be suspended between or passed between these spaced members and also rotated with respect to the frame when the device is secured to the spaced members.

  16. Aircraft landing gear systems

    NASA Technical Reports Server (NTRS)

    Tanner, John A. (Editor)

    1990-01-01

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

  17. Tritium handling in vacuum systems

    SciTech Connect

    Gill, J.T.; Coffin, D.O.

    1986-10-01

    This report provides a course in Tritium handling in vacuum systems. Topics presented are: Properties of Tritium; Tritium compatibility of materials; Tritium-compatible vacuum equipment; and Tritium waste treatment.

  18. Dazomet Fumigant Safe Handling Guide

    EPA Pesticide Factsheets

    Dazomet is the active ingredient in Basamid G soil fumigant pesticide. Wear personal protective equipment such as respirators when handling Basamid granules or making an application, mitigate exposures, and recognize signs of vapor inhalation.

  19. Ergonomic material-handling device

    DOEpatents

    Barsnick, Lance E.; Zalk, David M.; Perry, Catherine M.; Biggs, Terry; Tageson, Robert E.

    2004-08-24

    A hand-held ergonomic material-handling device capable of moving heavy objects, such as large waste containers and other large objects requiring mechanical assistance. The ergonomic material-handling device can be used with neutral postures of the back, shoulders, wrists and knees, thereby reducing potential injury to the user. The device involves two key features: 1) gives the user the ability to adjust the height of the handles of the device to ergonomically fit the needs of the user's back, wrists and shoulders; and 2) has a rounded handlebar shape, as well as the size and configuration of the handles which keep the user's wrists in a neutral posture during manipulation of the device.

  20. Handling Procedures of Vegetable Crops

    NASA Technical Reports Server (NTRS)

    Perchonok, Michele; French, Stephen J.

    2004-01-01

    The National Aeronautics and Space Administration (NASA) is working towards future long duration manned space flights beyond low earth orbit. The duration of these missions may be as long as 2.5 years and will likely include a stay on a lunar or planetary surface. The primary goal of the Advanced Food System in these long duration exploratory missions is to provide the crew with a palatable, nutritious, and safe food system while minimizing volume, mass, and waste. Vegetable crops can provide the crew with added nutrition and variety. These crops do not require any cooking or food processing prior to consumption. The vegetable crops, unlike prepackaged foods, will provide bright colors, textures (crispy), and fresh aromas. Ten vegetable crops have been identified for possible use in long duration missions. They are lettuce, spinach, carrot, tomato, green onion, radish, bell pepper, strawberries, fresh herbs, and cabbage. Whether these crops are grown on a transit vehicle (e.g., International Space Station) or on the lunar or planetary surface, it will be necessary to determine how to safely handle the vegetables while maintaining acceptability. Since hydrogen peroxide degrades into water and oxygen and is generally recognized as safe (GRAS), hydrogen peroxide has been recommended as the sanitizer. The objective of th is research is to determine the required effective concentration of hydrogen peroxide. In addition, it will be determined whether the use of hydrogen peroxide, although a viable sanitizer, adversely affects the quality of the vegetables. Vegetables will be dipped in 1 % hydrogen peroxide, 3% hydrogen peroxide, or 5% hydrogen peroxide. Treated produce and controls will be stored in plastic bags at 5 C for up to 14 days. Sensory, color, texture, and total plate count will be measured. The effect on several vegetables including lettuce, radish, tomato and strawberries has been completed. Although each vegetable reacts to hydrogen peroxide differently, the

  1. Material Handling in Dry Docks.

    DTIC Science & Technology

    1981-11-01

    final report of work completed under Naval Sea Systems Command Work Request N0002470WR9666 to identify segments of drydock material handling which may... segment of drydock/shipboard material handling which may be improved to achieve reductions in manhours and overhaul costs for typical availabilities...IAN’ Earthquake criteria, regardless of geograp tical area, which can eliminate anywhere from 1/3 to 1/2 of the blocks required and meet an additional

  2. A STUDY OF CONVENTIONAL AIRPLANE HANDLING QUALITIES REQUIREMENTS. PART 1. ROLL HANDLING QUALITIES

    DTIC Science & Technology

    concerned with bank angle per se, but rather with attaining a mentally commanded bank angle with tolerable accuracy in a reasonable time , and with an easily learned and comfortable program of aileron movements.

  3. Small transport aircraft technology

    NASA Technical Reports Server (NTRS)

    Williams, L. J.

    1983-01-01

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

  4. Design of a turbofan powered regional transport aircraft

    NASA Technical Reports Server (NTRS)

    1991-01-01

    The majority of the market for small commercial transport aircraft is dominated by high efficiency propeller driven aircraft of non-U.S. manufacture. During the past year, an aircraft was designed with ranges of up to 1500 nautical miles and passenger loads between 50 and 90. Special emphasis was placed upon keeping acquisition cost and direct operating costs at a low level while providing passengers with quality comfort levels. Several designs are presented which place a high premium on design innovation.

  5. A Method for Implementing QP-4, an Air Force Logistics Command Quality Assurance Program, in a Base Level Aircraft Maintenance Organization

    DTIC Science & Technology

    1989-09-01

    Document the improved process. 30 j . Control the process (use statistical process control charts) (23:4). Chapter Summary This chapter established a...Competitive Position. Massachusetts Institute of Technology, Center for Advanced Engineering Study, 1982. 6. Dreyfuss, J . "Victories in the Quality...WPAFB, June 1988. 12. Heldt, J . "Quality Pays," Quality, 27: 26-7 (November 1988). 13. Jaraiedi, M. "Multiple Inspections to Meet Desired Outgoing

  6. A robotic manipulator for handling TLD badges.

    PubMed

    Levinson, S; Weinstein, M; Abraham, A; German, U; Gorelik, V; Rozenfeld, R; Hillel, S; Rodnay, G

    2008-11-01

    A prototype system for automatic handling of Harshaw/Bicron (now ThermoFisher Scientific) thermoluminescent dosimetry (TLD) badges, which is based on a robotic arm, was designed and built. The robot performs the loading and unloading of the TLD cards in the badges and transports them between the loading/unloading station and magazine stations. For quality assurance, a sticker containing the worker's details printed in barcode format was added to the badge. Automatic on-line identification is performed for checking the correlation between the badge and the TLD card number.

  7. Aircraft Abnormal Conditions Detection, Identification, and Evaluation Using Innate and Adaptive Immune Systems Interaction

    NASA Astrophysics Data System (ADS)

    Al Azzawi, Dia

    Abnormal flight conditions play a major role in aircraft accidents frequently causing loss of control. To ensure aircraft operation safety in all situations, intelligent system monitoring and adaptation must rely on accurately detecting the presence of abnormal conditions as soon as they take place, identifying their root cause(s), estimating their nature and severity, and predicting their impact on the flight envelope. Due to the complexity and multidimensionality of the aircraft system under abnormal conditions, these requirements are extremely difficult to satisfy using existing analytical and/or statistical approaches. Moreover, current methodologies have addressed only isolated classes of abnormal conditions and a reduced number of aircraft dynamic parameters within a limited region of the flight envelope. This research effort aims at developing an integrated and comprehensive framework for the aircraft abnormal conditions detection, identification, and evaluation based on the artificial immune systems paradigm, which has the capability to address the complexity and multidimensionality issues related to aircraft systems. Within the proposed framework, a novel algorithm was developed for the abnormal conditions detection problem and extended to the abnormal conditions identification and evaluation. The algorithm and its extensions were inspired from the functionality of the biological dendritic cells (an important part of the innate immune system) and their interaction with the different components of the adaptive immune system. Immunity-based methodologies for re-assessing the flight envelope at post-failure and predicting the impact of the abnormal conditions on the performance and handling qualities are also proposed and investigated in this study. The generality of the approach makes it applicable to any system. Data for artificial immune system development were collected from flight tests of a supersonic research aircraft within a motion-based flight

  8. Handling Flight-Research Data In Real Time

    NASA Technical Reports Server (NTRS)

    Moore, Archie L.

    1988-01-01

    Researchers at widely separated locations able to participate in tests and analyze data immediately. Basic data-handling needs common: Communicates with vehicle, pilot, and test team; Acquires, computes, and displays data; knows exact location of research vehicle at all times. Continuing challenge for designers and operators of ground support facilities to perform tasks in real time and present integrated results to research team in real time. Paper presents several approaches to satisfaction of requirements of representative types of aircraft research programs at NASA Western Aeronautical Test Range of Ames Research Center.

  9. Directional monitoring terminal for aircraft noise

    NASA Astrophysics Data System (ADS)

    Genescà, M.

    2016-07-01

    This paper presents a concept of an aircraft noise monitoring terminal (NMT) that reduces background noise and the influence of ground reflection, in comparison with a single microphone. Also, it automatically identifies aircraft sound events based on the direction of arrival of the sound rather than on the sound pressure level (or radar data). And moreover, it provides an indicator of the quality of the sound pressure level measurement, i.e. if it is possibly disturbed by extraneous sources. The performance of this NMT is experimentally tested under real conditions in a measurement site close to Zurich airport. The results show that the NMT unambiguously identifies the noise events generated by the target aircraft, correctly detects those aircraft noise events that may be disturbed by the presence of other sources, and offers a substantial reduction in background and ground reflected sound.

  10. Handling target obscuration through Markov chain observations

    NASA Astrophysics Data System (ADS)

    Kouritzin, Michael A.; Wu, Biao

    2008-04-01

    Target Obscuration, including foliage or building obscuration of ground targets and landscape or horizon obscuration of airborne targets, plagues many real world filtering problems. In particular, ground moving target identification Doppler radar, mounted on a surveillance aircraft or unattended airborne vehicle, is used to detect motion consistent with targets of interest. However, these targets try to obscure themselves (at least partially) by, for example, traveling along the edge of a forest or around buildings. This has the effect of creating random blockages in the Doppler radar image that move dynamically and somewhat randomly through this image. Herein, we address tracking problems with target obscuration by building memory into the observations, eschewing the usual corrupted, distorted partial measurement assumptions of filtering in favor of dynamic Markov chain assumptions. In particular, we assume the observations are a Markov chain whose transition probabilities depend upon the signal. The state of the observation Markov chain attempts to depict the current obscuration and the Markov chain dynamics are used to handle the evolution of the partially obscured radar image. Modifications of the classical filtering equations that allow observation memory (in the form of a Markov chain) are given. We use particle filters to estimate the position of the moving targets. Moreover, positive proof-of-concept simulations are included.

  11. Aircraft Observations of Aerosol Composition and Ageing in New England and Mid-Atlantic States during the Summer 2002 New England Air Quality Study Field Campaign

    SciTech Connect

    Kleinman, Lawrence I.; Daum, Peter H.; Lee, Y.- N.; Senum, Gunar; Springston, Stephen R.; Wang, Jian; Berkowitz, Carl M.; Hubbe, John M.; Zaveri, Rahul A.; Brechtel, Fred J.; Jayne, J. T.; Onasch, Timothy B.; Worsnop, Douglas R.

    2007-05-11

    Aerosol chemical composition, size distributions, and optical properties were measured during 17 aircraft flights in New England and Middle Atlantic States as part of the summer 2002 NEAQS field campaign. An Aerodyne Aerosol Mass Spectrometer (AMS) was operated with a measurement cycle of 30 s, about an order of magnitude faster than used for ground-based measurements. Noise levels within a single measurement period were sub μg m-3. Volume data derived from the AMS were compared with volume measurements from a PCASP optical particle detector and an Scanning Mobility Particle Spectrometer (SMPS); calculated light scattering was compared with measured values from an integrating nephelometer. The median ratio for AMS/SMPS volume was 1.25; the median ratio for AMS/nephelometer scattering was 1.18. Size spectra were compared for subsets of samples with different effective diameters (Deff). There is good agreement between the AMS, PCASP, and SMPS spectra for larger values of Deff but an unexplained over-prediction in the AMS for small values. A dependence of the AMS collection efficiency on aerosol acidity was quantified by a comparison between AMS and PCASP volumes in 2 high sulfate plumes. Average aerosol concentrations were 11 μg m-3. The organic content was high in comparison to monitoring data from the IMPROVE network, varying from 70% in clean air to 40% in high concentration sulfate plumes. The ratio of organic aerosol to CO and light absorption acting were examined as a function of photochemical age. CO is a conservative tracer for urban emissions and light absorption is a surrogate for black carbon which is also conservative. Comparisons were made to surface ratios measured under conditions where there is little secondary organic aerosol (SOA). An increase in these ratios relative to surface values indicates that 70 - 80% of the organic aerosol in polluted air masses was secondary. Most of this SOA is rapidly formed within a few hours. At longer time scales

  12. Raptors and aircraft

    USGS Publications Warehouse

    Smith, D.G.; Ellis, D.H.; Johnson, T.H.; Glinski, Richard L.; Pendleton, Beth Giron; Moss, Mary Beth; LeFranc, Maurice N.=; Millsap, Brian A.; Hoffman, Stephen W.

    1988-01-01

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

  13. Characterization of emissions from commercial aircraft engines during the Aircraft Particle Emissions eXperiment (APEX) 1 to 3

    EPA Science Inventory

    The fine particulate matter emissions from aircraft operations at large airports located in areas of the U. S. designated as non-attainment for the National Ambient Air Quality Standard for PM-2.5 are of major environmental concern. PM emissions data for commercial aircraft engin...

  14. Aircraft Survivability. Spring 2009

    DTIC Science & Technology

    2009-01-01

    Surviving an Aircraft Crash with Airbag Restraintsby Thomas Barth Inflatable restraint solutions have improved the survivability of commercial...Surviving an Aircraft Crash with Airbag Restraints by Thomas Barth Transport Aircraft Interiors The AmSafe Aviation Airbag entered service on commercial...all night.” Keithley also noted that, in his early days at BRL, Walt teamed up with a group of like-minded innovators, including Jim Foulk, Roland

  15. Lightning effects on aircraft

    NASA Technical Reports Server (NTRS)

    1977-01-01

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

  16. Automation effects in a stereotypical multiloop manual control system. [for aircraft

    NASA Technical Reports Server (NTRS)

    Hess, R. A.; Mcnally, B. D.

    1984-01-01

    The increasing reliance of state-of-the art, high performance aircraft on high authority stability and command augmentation systems, in order to obtain satisfactory performance and handling qualities, has made critical the achievement of a better understanding of human capabilities, limitations, and preferences during interactions with complex dynamic systems that involve task allocation between man and machine. An analytical and experimental study has been undertaken to investigate human interaction with a simple, multiloop dynamic system in which human activity was systematically varied by changing the levels of automation. Task definition has led to a control loop structure which parallels that for any multiloop manual control system, and may therefore be considered a stereotype.

  17. Hypersonic aircraft design

    NASA Technical Reports Server (NTRS)

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

    1990-01-01

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

  18. Structureborne noise in aircraft

    NASA Technical Reports Server (NTRS)

    Clevenson, S. A.; Metcalf, V. L.

    1987-01-01

    The amount of noise reaching an aircraft's interior by structureborne paths, when high levels of other noises are present, involves the measurement of transfer functions between vibrating levels on the wing and interior noise. The magnitude of the structureborne noise transfer function is established by exciting the aircraft with an electrodynamic shaker; a second transfer function is measured using the same sensor locations with the aircraft engines operating. Attention is given to the case of a twin-turboprop OV-10A aircraft; the resulting transfer function values at the discrete frequencies corresponding to the propeller blade passage frequency and its first four harmonics are tabulated and illustrated.

  19. Development of Longitudinal Equivalent System Models for Selected U.S. Navy Tactical Aircraft

    DTIC Science & Technology

    1981-08-01

    revaraa side II nacaaaary and Identlly by block number) Aircraft Longitudinal Flying Qualities Equivalent Systems Frequency Response Matching...is a twin turbofan powered, land and carrier based, subsonic, anti- submarine warfare aircraft . Longitudinal control is accomplished via a...based, supersonic fighter aircraft . Longitudinal control is accomplished via an irreversible mechanical flight control system which transmits

  20. CANISTER HANDLING FACILITY CRITICALITY SAFETY CALCULATIONS

    SciTech Connect

    C.E. Sanders

    2005-04-07

    This design calculation revises and updates the previous criticality evaluation for the canister handling, transfer and staging operations to be performed in the Canister Handling Facility (CHF) documented in BSC [Bechtel SAIC Company] 2004 [DIRS 167614]. The purpose of the calculation is to demonstrate that the handling operations of canisters performed in the CHF meet the nuclear criticality safety design criteria specified in the ''Project Design Criteria (PDC) Document'' (BSC 2004 [DIRS 171599], Section 4.9.2.2), the nuclear facility safety requirement in ''Project Requirements Document'' (Canori and Leitner 2003 [DIRS 166275], p. 4-206), the functional/operational nuclear safety requirement in the ''Project Functional and Operational Requirements'' document (Curry 2004 [DIRS 170557], p. 75), and the functional nuclear criticality safety requirements described in the ''Canister Handling Facility Description Document'' (BSC 2004 [DIRS 168992], Sections 3.1.1.3.4.13 and 3.2.3). Specific scope of work contained in this activity consists of updating the Category 1 and 2 event sequence evaluations as identified in the ''Categorization of Event Sequences for License Application'' (BSC 2004 [DIRS 167268], Section 7). The CHF is limited in throughput capacity to handling sealed U.S. Department of Energy (DOE) spent nuclear fuel (SNF) and high-level radioactive waste (HLW) canisters, defense high-level radioactive waste (DHLW), naval canisters, multicanister overpacks (MCOs), vertical dual-purpose canisters (DPCs), and multipurpose canisters (MPCs) (if and when they become available) (BSC 2004 [DIRS 168992], p. 1-1). It should be noted that the design and safety analyses of the naval canisters are the responsibility of the U.S. Department of the Navy (Naval Nuclear Propulsion Program) and will not be included in this document. In addition, this calculation is valid for the current design of the CHF and may not reflect the ongoing design evolution of the facility

  1. A glovebox with three levels of containment and clean room facilities for growing and handling biological material at physiologically correct gas compositions and with optimal quality assessment for tissue-engineering, ex vivo expansion, manipulation and gene therapy.

    PubMed

    Villadsen, J A; Voeten, R G H M; Mosborg Peterson, P

    2002-07-01

    Traditional two levels of containment provide enclosure and underpressure in order to avoid hazardous material to flow towards e.g. a crewmember and thereby cause severe harm. The present-day demands for laboratory safety have revealed a paradox: In the laboratory overpressure is needed to prevent contamination of biological material and under pressure is needed to prevent the pollution of the environment. A new type of combined workbench/incubator has been constructed to meet future regulatory demands for handling and growing human biological cellular material at safe constant physiological conditions: A so-called three levels of containment glovebox/workbench. This new invention avoids the hazards of prior technology. It sets new standards for proper handling of biological materials and will meet the coming safety demands from the growing field of tissue engineering and ex vivo biotechnology. The invention is computer controlled, has a build in cleaning facility for assuring a particle free and aseptic working facility. We now have invented a solution to the above paradox concerning laboratory safety that seems to fulfil the need for safe biological experiments in microgravity. This concept has already been applied into ground-based research and is expected in a few years also to be applied similarly in the ISS environment. Furthermore, handling biological material mimicking in vivo conditions ex vivo requires precise and stabile monitoring and regulation of the isotherm and isobar conditions. Handling stem cells requires in addition low to very low oxygen tension to mimic the stem cells natural habitats. Besides that, the ex vivo gaseous atmosphere and temperature surrounding the cells has to be of same correct composition and temperature as found in the body in order to mimic in vivo situations in such way, that scientifically correct, reproducible and comparable results can be achieved. This fact is strengthened by forthcoming regulations as being prepared by

  2. Trimming an aircraft model for flight simulation

    NASA Technical Reports Server (NTRS)

    Mcfarland, Richard E.

    1987-01-01

    Real-time piloted aircraft simulations with digital computers have been performed at Ames Research Center (ARC) for over two decades. For the simulation of conventional aircraft models, the establishment of initial vehicle and control orientations at various operational flight regimes has been adequately handled by either analog techniques or simple inversion processes. However, exotic helicopter configurations have been introduced recently that require more sophisticated techniques because of their expanded degrees of freedom and environmental vibration levels. At ARC, these techniques are used for the backward solutions to real-time simulation models as required for the generation of trim points. These techniques are presented in this paper with examples from a blade-element helicopter simulation model.

  3. Aircraft Anomaly Detection Using Performance Models Trained on Fleet Data

    NASA Technical Reports Server (NTRS)

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

    2012-01-01

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

  4. 7 CFR 906.7 - Handle.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 8 2010-01-01 2010-01-01 false Handle. 906.7 Section 906.7 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Marketing Agreements and... GRANDE VALLEY IN TEXAS Order Regulating Handling Definitions § 906.7 Handle. Handle or ship means...

  5. 7 CFR 959.7 - Handle.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 8 2010-01-01 2010-01-01 false Handle. 959.7 Section 959.7 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Marketing Agreements and... Handling Definitions § 959.7 Handle. Handle or ship means to package, load, sell, transport, or in any...

  6. 7 CFR 946.7 - Handle.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 8 2010-01-01 2010-01-01 false Handle. 946.7 Section 946.7 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Marketing Agreements and... Regulating Handling Definitions § 946.7 Handle. Handle is synonymous with ship and means to transport,...

  7. 7 CFR 958.7 - Handle.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 8 2010-01-01 2010-01-01 false Handle. 958.7 Section 958.7 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Marketing Agreements and... IN IDAHO, AND MALHEUR COUNTY, OREGON Order Regulating Handling Definitions § 958.7 Handle. Handle...

  8. Portable vacuum object handling device

    DOEpatents

    Anderson, Gordon H.

    1983-08-09

    The disclosure relates to a portable device adapted to handle objects which are not to be touched by hand. A piston and bore wall form a vacuum chamber communicating with an adaptor sealably engageable with an object to be lifted. The piston is manually moved and set to establish vacuum. A valve is manually actuatable to apply the vacuum to lift the object.

  9. General Aviation Aircraft Reliability Study

    NASA Technical Reports Server (NTRS)

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

    2001-01-01

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

  10. BICARBONATE OF SODA BLASTING TECHNOLOGY FOR AIRCRAFT WHEEL PAINTING

    EPA Science Inventory

    This evaluation addressed product quality, waste reduction/pollution prevention and economics in replacing chemical solvent strippers with a bicarbonate of soda blasting technology for removal of paint from aircraft wheels. The evaluation was conducted in the Paint Stripping Sho...

  11. Development and Evaluation of an Air Quality Modeling Approach to Assess Near-Field Impacts of Lead Emissions from Piston-Engine Aircraft Operating on Leaded Aviation Gasoline

    EPA Science Inventory

    Since aviation gasoline is now the largest remaining source of lead (Pb) emissions to the air in the United States, there is increased interest by regulatory agencies and the public in assessing the impacts on residents living in close proximity to these sources. An air quality m...

  12. Study of dynamics of X-14B VTOL aircraft

    NASA Technical Reports Server (NTRS)

    Loscutoff, W. V.; Mitchiner, J. L.; Roesener, R. A.; Seevers, J. A.

    1973-01-01

    Research was initiated to investigate certain facets of modern control theory and their integration with a digital computer to provide a tractable flight control system for a VTOL aircraft. Since the hover mode is the most demanding phase in the operation of a VTOL aircraft, the research efforts were concentrated in this mode of aircraft operation. Research work on three different aspects of the operation of the X-14B VTOL aircraft is discussed. A general theory for optimal, prespecified, closed-loop control is developed. The ultimate goal was optimal decoupling of the modes of the VTOL aircraft to simplify the pilot's task of handling the aircraft. Modern control theory is used to design deterministic state estimators which provide state variables not measured directly, but which are needed for state variable feedback control. The effect of atmospheric turbulence on the X-14B is investigated. A maximum magnitude gust envelope within which the aircraft could operate stably with the available control power is determined.

  13. An aircraft manufacturer's approach to rideability criteria

    NASA Technical Reports Server (NTRS)

    Omassey, R. C.; Leve, H.; Gaume, J. G.

    1972-01-01

    The approach of an aircraft manufacturer to ride quality in air transportation is presented. The subjects discussed are: (1) the external and internal environment in terms of vibration and acoustic sources and general response, (2) guidelines and criteria reflecting current practice, (3) present and future efforts to develop rideability criteria, and (4) requirements for data, criteria, and research in various rideability areas.

  14. Assessment of Alternative Aircraft Fuels

    NASA Technical Reports Server (NTRS)

    1984-01-01

    The purpose of this symposium is to provide representatives from industry, government, and academia concerned with the availability and quality of future aviation turbine fuels with recent technical results and a status review of DOD and NASA sponsored fuels research projects. The symposium has included presentations on the potential crude sources, refining methods, and characteristics of future fuels; the effects of changing fuel characteristics on the performance and durability of jet aircraft components and systems; and the prospects for evolving suitable technology to produce and use future fuels.

  15. Cable Tensiometer for Aircraft

    NASA Technical Reports Server (NTRS)

    Nunnelee, Mark (Inventor)

    2008-01-01

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

  16. Aircraft landing control system

    NASA Technical Reports Server (NTRS)

    Lambregts, Antonius A. (Inventor); Hansen, Rolf (Inventor)

    1982-01-01

    Upon aircraft landing approach, flare path command signals of altitude, vertical velocity and vertical acceleration are generated as functions of aircraft position and velocity with respect to the ground. The command signals are compared with corresponding actual values to generate error signals which are used to control the flight path.

  17. Predicting Aircraft Availability

    DTIC Science & Technology

    2013-06-01

    ENS- GRP -13-J-2 DEPARTMENT OF THE AIR FORCE AIR UNIVERSITY AIR FORCE INSTITUTE OF TECHNOLOGY Wright-Patterson Air Force Base, Ohio...AFIT-ENS- GRP -13-J-2 PREDICTING AIRCRAFT AVAILABILITY GRADUATE RESEARCH PROJECT Presented to the Faculty Department of Operational...APPROVED FOR PUBLIC RELEASE; DISTRIBUTION UNLIMITED AFIT-ENS- GRP -13-J-2 PREDICTING AIRCRAFT AVAILABILITY Mark A. Chapa

  18. Why aircraft disinsection?

    PubMed

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

    2000-01-01

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

  19. Why aircraft disinsection?

    PubMed Central

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

    2000-01-01

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

  20. Aircraft operations management manual

    NASA Technical Reports Server (NTRS)

    1992-01-01

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

  1. A strategic planning methodology for aircraft redesign

    NASA Astrophysics Data System (ADS)

    Romli, Fairuz Izzuddin

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

  2. Flying-qualities criteria for wings-level-turn maneuvering during an air-to-ground weapon delivery task

    NASA Technical Reports Server (NTRS)

    Sammonds, R. I.; Bunnell, J. W.

    1981-01-01

    A moving base simulator experiment demonstrated that a wings-level-turn control mode improved flying qualities for air to ground weapon delivery compared with those of a conventionally controlled aircraft. Evaluations of criteria for dynamic response for this system have shown that pilot ratings correlate well on the basis of equivalent time constant of the initial response. Ranges of this time constant, as well as digital system transport delays and lateral acceleration control authorities that encompassed level 1 through 3 handling qualities, were determined.

  3. Flying-qualities criteria for wings-level-turn maneuvering during an air-to-ground weapon delivery task

    NASA Technical Reports Server (NTRS)

    Sammonds, R. I.; Bunnell, J. W., Jr.

    1980-01-01

    A moving-base simulator experiment conducted at Ames Research Center demonstrated that a wings-level-turn control mode improved flying qualities for air-to-ground weapons delivery compared with those of a conventional aircraft. Evaluations of criteria for dynamic response for this system have shown that pilot ratings correlate well on the basis of equivalent time constant of the initial response. Ranges of this time constant, as well as digital-system transport delays and lateral-acceleration control authorities that encompassed Level I through Level III handling qualities, were determined.

  4. Centralized FITS Metadata Handling Framework at ESO

    NASA Astrophysics Data System (ADS)

    Vera, I.; Dobrzycki, A.; Vuong, M.-H.; Brion, A.

    2011-07-01

    The European Organization for Astronomical Research in the Southern Hemisphere (ESO) headquartered in Garching, Germany, operates three state-of-the-art observatories in Chile: at La Silla, Paranal and Chajnantor. The observatories produce huge amounts of data, which are transferred to the ESO headquarters and stored in the ESO Archive. The archive also stores the products generated by pipeline processing of raw data by the ESO Quality Control (QC) group. In addition, the Archive also stores science products delivered by the principal investigators. Historically, these three processes were independent from one another which resulted in different metadata handling frameworks for each kind of product. This architecture led to duplicate efforts for building metadata-based services as well as creating challenging scenarios for integrating metadata from different processes. We present the metadata handling framework recently implemented at the European Southern Observatory, in which all metadata from FITS compliant sources are stored in a centralized repository database. The framework allows building metadata-based services in a descriptive way, transparently propagating any modifications/updates performed in the central repository. In addition, through a set of common functions, the framework allows for enrichment of FITS-based metadata with derived values and/or with metadata from other ESO operational databases.

  5. Chemical Characterization and Quality Control for an Adhesive.

    DTIC Science & Technology

    ADHESIVES, *IDENTIFICATION, *CHEMICAL ANALYSIS, *QUALITY CONTROL, PHYSICOCHEMICAL PROPERTIES, ACCEPTANCE TESTS, CLASSIFICATION, VIABILITY, TEST METHODS, ANALYTICAL CHEMISTRY, PROCESSING, PRODUCTION CONTROL , AIRCRAFT .

  6. The CDF data handling system

    SciTech Connect

    Dmitry O. Litvintsev

    2003-11-05

    The Collider Detector at Fermilab (CDF) records proton-antiproton collisions at center of mass energy of 2.0 TeV at the Tevatron collider. A new collider run, Run II, of the Tevatron started in April 2001. Increased luminosity will result in about 1 PB of data recorded on tapes in the next two years. Currently the CDF experiment has about 260 TB of data stored on tapes. This amount includes raw and reconstructed data and their derivatives. The data storage and retrieval are managed by the CDF Data Handling (DH) system. This system has been designed to accommodate the increased demands of the Run II environment and has proven robust and reliable in providing reliable flow of data from the detector to the end user. This paper gives an overview of the CDF Run II Data Handling system which has evolved significantly over the course of this year. An outline of the future direction of the system is given.

  7. Portable vacuum object handling device

    DOEpatents

    Anderson, G.H.

    1983-08-09

    The disclosure relates to a portable device adapted to handle objects which are not to be touched by hand. A piston and bore wall form a vacuum chamber communicating with an adaptor sealably engageable with an object to be lifted. The piston is manually moved and set to establish vacuum. A valve is manually actuatable to apply the vacuum to lift the object. 1 fig.

  8. Piloted aircraft simulation concepts and overview

    NASA Technical Reports Server (NTRS)

    Sinacori, J. B.

    1978-01-01

    An overview of piloted aircraft simulation is presented that reflects the viewpoint of an aeronautical technologist. The intent is to acquaint potential users with some of the basic concepts and issues that characterize piloted simulation. Application to the development of aircraft are highlighted, but some aspects of training simulators are covered. A historical review is given together with a description of some current simulators. Simulator usages, advantages, and limitations are discussed and human perception qualities important to simulation are related. An assessment of current simulation is presented that addresses validity, fidelity, and deficiencies. Future prospects are discussed and technology projections are made.

  9. Predicting Visibility of Aircraft

    PubMed Central

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

    2009-01-01

    Visual detection of aircraft by human observers is an important element of aviation safety. To assess and ensure safety, it would be useful to be able to be able to predict the visibility, to a human observer, of an aircraft of specified size, shape, distance, and coloration. Examples include assuring safe separation among aircraft and between aircraft and unmanned vehicles, design of airport control towers, and efforts to enhance or suppress the visibility of military and rescue vehicles. We have recently developed a simple metric of pattern visibility, the Spatial Standard Observer (SSO). In this report we examine whether the SSO can predict visibility of simulated aircraft images. We constructed a set of aircraft images from three-dimensional computer graphic models, and measured the luminance contrast threshold for each image from three human observers. The data were well predicted by the SSO. Finally, we show how to use the SSO to predict visibility range for aircraft of arbitrary size, shape, distance, and coloration. PMID:19462007

  10. Predicting visibility of aircraft.

    PubMed

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

    2009-05-20

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

  11. Translator for Optimizing Fluid-Handling Components

    NASA Technical Reports Server (NTRS)

    Landon, Mark; Perry, Ernest

    2007-01-01

    A software interface has been devised to facilitate optimization of the shapes of valves, elbows, fittings, and other components used to handle fluids under extreme conditions. This software interface translates data files generated by PLOT3D (a NASA grid-based plotting-and- data-display program) and by computational fluid dynamics (CFD) software into a format in which the files can be read by Sculptor, which is a shape-deformation- and-optimization program. Sculptor enables the user to interactively, smoothly, and arbitrarily deform the surfaces and volumes in two- and three-dimensional CFD models. Sculptor also includes design-optimization algorithms that can be used in conjunction with the arbitrary-shape-deformation components to perform automatic shape optimization. In the optimization process, the output of the CFD software is used as feedback while the optimizer strives to satisfy design criteria that could include, for example, improved values of pressure loss, velocity, flow quality, mass flow, etc.

  12. Inductive Learning Approaches for Improving Pilot Awareness of Aircraft Faults

    NASA Technical Reports Server (NTRS)

    Spikovska, Lilly; Iverson, David L.; Poll, Scott; Pryor, anna

    2005-01-01

    Neural network flight controllers are able to accommodate a variety of aircraft control surface faults without detectable degradation of aircraft handling qualities. Under some faults, however, the effective flight envelope is reduced; this can lead to unexpected behavior if a pilot performs an action that exceeds the remaining control authority of the damaged aircraft. The goal of our work is to increase the pilot s situational awareness by informing him of the type of damage and resulting reduction in flight envelope. Our methodology integrates two inductive learning systems with novel visualization techniques. One learning system, the Inductive Monitoring System (IMS), learns to detect when a simulation includes faulty controls, while two others, Inductive Classification System (INCLASS) and multiple binary decision tree system (utilizing C4.5), determine the type of fault. In off-line training using only non-failure data, IMS constructs a characterization of nominal flight control performance based on control signals issued by the neural net flight controller. This characterization can be used to determine the degree of control augmentation required in the pitch, roll, and yaw command channels to counteract control surface failures. This derived information is typically sufficient to distinguish between the various control surface failures and is used to train both INCLASS and C4.5. Using data from failed control surface flight simulations, INCLASS and C4.5 independently discover and amplify features in IMS results that can be used to differentiate each distinct control surface failure situation. In real-time flight simulations, distinguishing features learned during training are used to classify control surface failures. Knowledge about the type of failure can be used by an additional automated system to alter its approach for planning tactical and strategic maneuvers. The knowledge can also be used directly to increase the pilot s situational awareness and

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

    NASA Technical Reports Server (NTRS)

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

    2013-01-01

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

  14. Some fighter aircraft trends

    NASA Technical Reports Server (NTRS)

    Spearman, L.

    1985-01-01

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

  15. Loftin Collection - Boeing Aircraft

    NASA Technical Reports Server (NTRS)

    1933-01-01

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

  16. Tropospheric sampling with aircraft

    SciTech Connect

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

    1991-03-01

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

  17. Aircraft compass characteristics

    NASA Technical Reports Server (NTRS)

    Peterson, John B; Smith, Clyde W

    1937-01-01

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

  18. OVRhyp, Scramjet Test Aircraft

    NASA Technical Reports Server (NTRS)

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

    1990-01-01

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

  19. Testing Aircraft Instruments.

    DTIC Science & Technology

    1981-02-11

    AD-A095 680 ARMY TEST AND EVALUATION COMMAND ABERDEEN PROVING GRO--ETC F/S 1/4 TESTING AIRCRAFT INSTRUMENTS .(U) FEB 81 CLASSIFIED TOP-6-3-013 ML I...Test and Evaluation Command -?Final 7, Ts .to .. eg----- ( -4_ Fia - / + I ORG REPORT STesting Aircraft Instruments , j P I- I. AUTHOR(es) S. CONTRACT...Identify by block number) This document presents information and procedures for testing aircraft flight and systems performance instruments in the functional

  20. Evaluating ammonia (NH3) predictions in the NOAA National Air Quality Forecast Capability (NAQFC) using in situ aircraft, ground-level, and satellite measurements from the DISCOVER-AQ Colorado campaign

    NASA Astrophysics Data System (ADS)

    Battye, William H.; Bray, Casey D.; Aneja, Viney P.; Tong, Daniel; Lee, Pius; Tang, Youhua

    2016-09-01

    The U.S. National Oceanic and Atmospheric Administration (NOAA) is responsible for forecasting elevated levels of air pollution within the National Air Quality Forecast Capability (NAQFC). The current research uses measurements gathered in the DISCOVER-AQ Colorado field campaign and the concurrent Front Range Air Pollution and Photochemistry Experiment (FRAPPE) to test performance of the NAQFC CMAQ modeling framework for predicting NH3. The DISCOVER-AQ and FRAPPE field campaigns were carried out in July and August 2014 in Northeast Colorado. Model predictions are compared with measurements of NH3 gas concentrations and the NH4+ component of fine particulate matter concentrations measured directly by the aircraft in flight. We also compare CMAQ predictions with NH3 measurements from ground-based monitors within the DISCOVER-AQ Colorado geographic domain, and from the Tropospheric Emission Spectrometer (TES) on the Aura satellite. In situ aircraft measurements carried out in July and August of 2014 suggest that the NAQFC CMAQ model underestimated the NH3 concentration in Northeastern Colorado by a factor of ∼2.7 (NMB = -63%). Ground-level monitors also produced a similar result. Average satellite-retrieved NH3 levels also exceeded model predictions by a factor of 1.5-4.2 (NMB = -33 to -76%). The underestimation of NH3 was not accompanied by an underestimation of particulate NH4+, which is further controlled by factors including acid availability, removal rate, and gas-particle partition. The average measured concentration of NH4+ was close to the average predication (NMB = +18%). Seasonal patterns measured at an AMoN site in the region suggest that the underestimation of NH3 is not due to the seasonal allocation of emissions, but to the overall annual emissions estimate. The underestimation of NH3 varied across the study domain, with the largest differences occurring in a region of intensive agriculture near Greeley, Colorado, and in the vicinity of Denver. The

  1. Modeling Programs Increase Aircraft Design Safety

    NASA Technical Reports Server (NTRS)

    2012-01-01

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

  2. 7 CFR 1205.312 - Handle.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (MARKETING AGREEMENTS AND ORDERS; MISCELLANEOUS COMMODITIES), DEPARTMENT OF AGRICULTURE COTTON RESEARCH AND PROMOTION Cotton Research and Promotion Order Definitions § 1205.312 Handle. Handle means to harvest, gin,...

  3. Solar thermal aircraft

    DOEpatents

    Bennett, Charles L.

    2007-09-18

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

  4. Aircraft parameter estimation

    NASA Technical Reports Server (NTRS)

    Iliff, Kenneth W.

    1987-01-01

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

  5. Laminar Flow Aircraft Certification

    NASA Technical Reports Server (NTRS)

    Williams, Louis J. (Compiler)

    1986-01-01

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

  6. Pollution reducing aircraft propulsion

    SciTech Connect

    Tamura, R. M.

    1985-05-28

    Aircraft engine exhaust is mixed with air and fuel and recombusted. Air is drawn into the secondary combustion chamber from suction surfaces on wings. Exhaust of the secondary combustion chamber is blown over wing and fuselage surfaces.

  7. The Aircraft Morphing Program

    NASA Technical Reports Server (NTRS)

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

    1998-01-01

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

  8. Aircraft electromagnetic compatibility

    NASA Technical Reports Server (NTRS)

    Clarke, Clifton A.; Larsen, William E.

    1987-01-01

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

  9. Aircraft Engine Emissions. [conference

    NASA Technical Reports Server (NTRS)

    1977-01-01

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

  10. Depreciation of aircraft

    NASA Technical Reports Server (NTRS)

    Warner, Edward P

    1922-01-01

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

  11. Aircraft Morphing program

    NASA Astrophysics Data System (ADS)

    Wlezien, Richard W.; Horner, Garnett C.; McGowan, Anna-Maria R.; Padula, Sharon L.; Scott, Michael A.; Silcox, Richard J.; Harrison, Joycelyn S.

    1998-06-01

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

  12. Advanced hypersonic aircraft design

    NASA Technical Reports Server (NTRS)

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

    1992-01-01

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

  13. ANALYSIS OF AIRCRAFT MOTIONS

    NASA Technical Reports Server (NTRS)

    Wingrove, R. C.

    1994-01-01

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

  14. Aircraft Survivability. Spring 2011

    DTIC Science & Technology

    2011-01-01

    advancing and applying technology to predict, evaluate , and improve combat survivability of US flight vehicles. John graduated from the University of...support for most of the aircraft and anti-aircraft programs conducted to date under LFT&E statutory requirements. A number of these test and evaluation ...initiatives to improve the state-of-the-art of LFT&E, to place greater emphasis on the evaluation of human casualties, to integrate Battle Damage

  15. Eagle RTS: A design for a regional transport aircraft

    NASA Technical Reports Server (NTRS)

    Bryer, Paul; Buckles, Jon; Lemke, Paul; Peake, Kirk

    1992-01-01

    This university design project concerns the Eagle RTS (Regional Transport System), a 66 passenger, twin turboprop aircraft with a range of 836 nautical miles. It will operate with a crew of two pilots and two flight attendents. This aircraft will employ the use of aluminum alloys and composite materials to reduce the aircraft weight and increase aerodynamic efficiency. The Eagle RTS will use narrow body aerodynamics with a canard configuration to improve performance. Leading edge technology will be used in the cockpit to improve flight handling and safety. The Eagle RTS propulsion system will consist of two turboprop engines with a total thrust of approximately 6300 pounds, 3150 pounds thrust per engine, for the cruise configuration. The engines will be mounted on the aft section of the aircraft to increase passenger safety in the event of a propeller failure. Aft mounted engines will also increase the overall efficiency of the aircraft by reducing the aircraft's drag. The Eagle RTS is projected to have a takeoff distance of approximately 4700 feet and a landing distance of 6100 feet. These distances will allow the Eagle RTS to land at the relatively short runways of regional airports.

  16. Aircraft as Research Tools

    NASA Technical Reports Server (NTRS)

    1999-01-01

    Aeronautical research usually begins with computers, wind tunnels, and flight simulators, but eventually the theories must fly. This is when flight research begins, and aircraft are the primary tools of the trade. Flight research involves doing precision maneuvers in either a specially built experimental aircraft or an existing production airplane that has been modified. For example, the AD-1 was a unique airplane made only for flight research, while the NASA F-18 High Alpha Research Vehicle (HARV) was a standard fighter aircraft that was transformed into a one-of-a-kind aircraft as it was fitted with new propulsion systems, flight controls, and scientific equipment. All research aircraft are able to perform scientific experiments because of the onboard instruments that record data about its systems, aerodynamics, and the outside environment. Since the 1970's, NASA flight research has become more comprehensive, with flights involving everything form Space Shuttles to ultralights. NASA now flies not only the fastest airplanes, but some of the slowest. Flying machines continue to evolve with new wing designs, propulsion systems, and flight controls. As always, a look at today's experimental research aircraft is a preview of the future.

  17. Automatic aircraft recognition

    NASA Astrophysics Data System (ADS)

    Hmam, Hatem; Kim, Jijoong

    2002-08-01

    Automatic aircraft recognition is very complex because of clutter, shadows, clouds, self-occlusion and degraded imaging conditions. This paper presents an aircraft recognition system, which assumes from the start that the image is possibly degraded, and implements a number of strategies to overcome edge fragmentation and distortion. The current vision system employs a bottom up approach, where recognition begins by locating image primitives (e.g., lines and corners), which are then combined in an incremental fashion into larger sets of line groupings using knowledge about aircraft, as viewed from a generic viewpoint. Knowledge about aircraft is represented in the form of whole/part shape description and the connectedness property, and is embedded in production rules, which primarily aim at finding instances of the aircraft parts in the image and checking the connectedness property between the parts. Once a match is found, a confidence score is assigned and as evidence in support of an aircraft interpretation is accumulated, the score is increased proportionally. Finally a selection of the resulting image interpretations with the highest scores, is subjected to competition tests, and only non-ambiguous interpretations are allowed to survive. Experimental results demonstrating the effectiveness of the current recognition system are given.

  18. 7 CFR 981.16 - To handle.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... AND ORDERS; FRUITS, VEGETABLES, NUTS), DEPARTMENT OF AGRICULTURE ALMONDS GROWN IN CALIFORNIA Order Regulating Handling Definitions § 981.16 To handle. To handle means to use almonds commercially of own production or to sell, consign, transport, ship (except as a common carrier of almonds owned by another)...

  19. 7 CFR 981.16 - To handle.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... and Orders; Fruits, Vegetables, Nuts), DEPARTMENT OF AGRICULTURE ALMONDS GROWN IN CALIFORNIA Order Regulating Handling Definitions § 981.16 To handle. To handle means to use almonds commercially of own production or to sell, consign, transport, ship (except as a common carrier of almonds owned by another)...

  20. 7 CFR 981.16 - To handle.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... and Orders; Fruits, Vegetables, Nuts), DEPARTMENT OF AGRICULTURE ALMONDS GROWN IN CALIFORNIA Order Regulating Handling Definitions § 981.16 To handle. To handle means to use almonds commercially of own production or to sell, consign, transport, ship (except as a common carrier of almonds owned by another)...

  1. 7 CFR 981.16 - To handle.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... AND ORDERS; FRUITS, VEGETABLES, NUTS), DEPARTMENT OF AGRICULTURE ALMONDS GROWN IN CALIFORNIA Order Regulating Handling Definitions § 981.16 To handle. To handle means to use almonds commercially of own production or to sell, consign, transport, ship (except as a common carrier of almonds owned by another)...

  2. 7 CFR 981.16 - To handle.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... and Orders; Fruits, Vegetables, Nuts), DEPARTMENT OF AGRICULTURE ALMONDS GROWN IN CALIFORNIA Order Regulating Handling Definitions § 981.16 To handle. To handle means to use almonds commercially of own production or to sell, consign, transport, ship (except as a common carrier of almonds owned by another)...

  3. 7 CFR 946.336 - Handling regulation.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... includes, but is not restricted to, potatoes for dehydration, chips, shoestrings, starch, and flour. It... Agreements and Orders; Fruits, Vegetables, Nuts), DEPARTMENT OF AGRICULTURE IRISH POTATOES GROWN IN WASHINGTON Handling Regulations § 946.336 Handling regulation. No person shall handle any lot of...

  4. 7 CFR 948.386 - Handling regulation.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ..., starch, and flour. It includes only that preparation of potatoes for market which involves the... AGREEMENTS AND ORDERS; FRUITS, VEGETABLES, NUTS), DEPARTMENT OF AGRICULTURE IRISH POTATOES GROWN IN COLORADO Handling Regulations § 948.386 Handling regulation. No person shall handle any lot of potatoes grown...

  5. 7 CFR 948.386 - Handling regulation.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ..., starch, and flour. It includes only that preparation of potatoes for market which involves the... Agreements and Orders; Fruits, Vegetables, Nuts), DEPARTMENT OF AGRICULTURE IRISH POTATOES GROWN IN COLORADO Handling Regulations § 948.386 Handling regulation. No person shall handle any lot of potatoes grown...

  6. 7 CFR 948.386 - Handling regulation.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... is not restricted to, potatoes for dehydration, chips, shoestrings, starch, and flour. It includes... AGREEMENTS AND ORDERS; FRUITS, VEGETABLES, NUTS), DEPARTMENT OF AGRICULTURE IRISH POTATOES GROWN IN COLORADO Handling Regulations § 948.386 Handling regulation. No person shall handle any lot of potatoes grown...

  7. 7 CFR 948.386 - Handling regulation.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... is not restricted to, potatoes for dehydration, chips, shoestrings, starch, and flour. It includes... Agreements and Orders; Fruits, Vegetables, Nuts), DEPARTMENT OF AGRICULTURE IRISH POTATOES GROWN IN COLORADO Handling Regulations § 948.386 Handling regulation. No person shall handle any lot of potatoes grown...

  8. 7 CFR 946.336 - Handling regulation.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... includes, but is not restricted to, potatoes for dehydration, chips, shoestrings, starch, and flour. It... AGREEMENTS AND ORDERS; FRUITS, VEGETABLES, NUTS), DEPARTMENT OF AGRICULTURE IRISH POTATOES GROWN IN WASHINGTON Handling Regulations § 946.336 Handling regulation. No person shall handle any lot of...

  9. 7 CFR 948.386 - Handling regulation.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ..., starch, and flour. It includes only that preparation of potatoes for market which involves the... Agreements and Orders; Fruits, Vegetables, Nuts), DEPARTMENT OF AGRICULTURE IRISH POTATOES GROWN IN COLORADO Handling Regulations § 948.386 Handling regulation. No person shall handle any lot of potatoes grown...

  10. 7 CFR 946.336 - Handling regulation.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... includes, but is not restricted to, potatoes for dehydration, chips, shoestrings, starch, and flour. It... AGREEMENTS AND ORDERS; FRUITS, VEGETABLES, NUTS), DEPARTMENT OF AGRICULTURE IRISH POTATOES GROWN IN WASHINGTON Handling Regulations § 946.336 Handling regulation. No person shall handle any lot of...

  11. 7 CFR 58.443 - Whey handling.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 3 2010-01-01 2010-01-01 false Whey handling. 58.443 Section 58.443 Agriculture... Procedures § 58.443 Whey handling. (a) Adequate sanitary facilities shall be provided for the handling of whey. If outside, necessary precautions shall be taken to minimize flies, insects and development...

  12. 7 CFR 947.7 - Handle.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 8 2010-01-01 2010-01-01 false Handle. 947.7 Section 947.7 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Marketing Agreements and... Definitions § 947.7 Handle. Handle is synonymous with ship and means to sell, transport, or in any other...

  13. 7 CFR 932.16 - Handle.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... Orders; Fruits, Vegetables, Nuts), DEPARTMENT OF AGRICULTURE OLIVES GROWN IN CALIFORNIA Order Regulating Handling Definitions § 932.16 Handle. Handle means to: (a) Size-grade olives, (b) process olives, or (c) use processed olives in the production of packaged olives, within the production area, or (d)...

  14. 7 CFR 932.16 - Handle.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... Orders; Fruits, Vegetables, Nuts), DEPARTMENT OF AGRICULTURE OLIVES GROWN IN CALIFORNIA Order Regulating Handling Definitions § 932.16 Handle. Handle means to: (a) Size-grade olives, (b) process olives, or (c) use processed olives in the production of packaged olives, within the production area, or (d)...

  15. 7 CFR 932.16 - Handle.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... ORDERS; FRUITS, VEGETABLES, NUTS), DEPARTMENT OF AGRICULTURE OLIVES GROWN IN CALIFORNIA Order Regulating Handling Definitions § 932.16 Handle. Handle means to: (a) Size-grade olives, (b) process olives, or (c) use processed olives in the production of packaged olives, within the production area, or (d)...

  16. 7 CFR 932.16 - Handle.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... Orders; Fruits, Vegetables, Nuts), DEPARTMENT OF AGRICULTURE OLIVES GROWN IN CALIFORNIA Order Regulating Handling Definitions § 932.16 Handle. Handle means to: (a) Size-grade olives, (b) process olives, or (c) use processed olives in the production of packaged olives, within the production area, or (d)...

  17. 7 CFR 932.16 - Handle.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... ORDERS; FRUITS, VEGETABLES, NUTS), DEPARTMENT OF AGRICULTURE OLIVES GROWN IN CALIFORNIA Order Regulating Handling Definitions § 932.16 Handle. Handle means to: (a) Size-grade olives, (b) process olives, or (c) use processed olives in the production of packaged olives, within the production area, or (d)...

  18. 3rd International Conference on Stability and Handling of Liquid Fuels

    DTIC Science & Technology

    1988-12-07

    and thermal stability of gasolines, jet fuels, diesel fuels, residual fuels and crude oils. Certain aspects of the handling of these materials were...LCO fractions obtained by distillation is also reported, demonstrating that removal of 315*C+ material greatly improves stability. Analytical results...the whole study are presented in the form of summary tables. Organic materials derived from the aircraft system were found to be major contributors to

  19. The community response to aircraft noise around six Spanish airports

    NASA Astrophysics Data System (ADS)

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

    1993-06-01

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

  20. Propeller aircraft interior noise model utilization study and validation

    NASA Technical Reports Server (NTRS)

    Pope, L. D.

    1984-01-01

    Utilization and validation of a computer program designed for aircraft interior noise prediction is considered. The program, entitled PAIN (an acronym for Propeller Aircraft Interior Noise), permits (in theory) predictions of sound levels inside propeller driven aircraft arising from sidewall transmission. The objective of the work reported was to determine the practicality of making predictions for various airplanes and the extent of the program's capabilities. The ultimate purpose was to discern the quality of predictions for tonal levels inside an aircraft occurring at the propeller blade passage frequency and its harmonics. The effort involved three tasks: (1) program validation through comparisons of predictions with scale-model test results; (2) development of utilization schemes for large (full scale) fuselages; and (3) validation through comparisons of predictions with measurements taken in flight tests on a turboprop aircraft. Findings should enable future users of the program to efficiently undertake and correctly interpret predictions.

  1. CFD Modeling & Verification in an Aircraft Paint Hangar

    DTIC Science & Technology

    2011-05-01

    Collaboration •Navy Bureau of Medicine and Surgery (BUMED), IH Division –Assists CNO with health and safety of Navy aircraft artisans –Quarterly monitoring...levels • Handling paint particulates and vapors 10 E2S2. Verification Pitfalls • Artisans change process in the weeks between baseline and...verification – Added a fabric blanket in front of filter to save filter bank blocking exhaust airflow during sanding • Learn how to go w/o sleep

  2. 150 Passenger Commercial Aircraft

    NASA Technical Reports Server (NTRS)

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

    2002-01-01

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

  3. Measurement of surface scratches on aircraft structures

    NASA Astrophysics Data System (ADS)

    Sarr, Dennis P.

    1996-01-01

    In assuring the quality of aircraft, the skin quality must be free of surface imperfections. Surface imperfections such as scratches are unacceptable for cosmetic and structural reasons. Scratches beyond a certain depth are not repairable, resulting in costly replacement of an aircraft's part. Measurements of aircraft exterior surfaces require a ladder or cherry picker for positioning the inspector. Commercially-available computer vision systems are not portable, easy to use, or ergonomic. The machine vision system must be designed with these criteria in mind. The scratch measurement system (SMS) uses computer vision, digital signal processing, and automated inspection methods. The system is portable and battery powered. It is certified for measuring the depth and width of the anomaly. The SMS provides a comprehensive, analytical, and accurate reading. A hardcopy output provides a permanent record of the analysis. The graphical data shows the surface profile and provides substantial information of the surface anomaly. The factory and flight line use the SMS at different stages of aircraft production. Six systems have been built for use within Boeing. A patent was issued for the SMS in February 1994.

  4. Supersonic Flying Qualities Experience Using the SR-71

    NASA Technical Reports Server (NTRS)

    Cox, Timothy H.; Jackson, Dante

    1997-01-01

    Approximately 25 years ago NASA Dryden Flight Research Center, Edwards, California, initiated the evaluation of supersonic handling qualities issues using the XB-70 and the YF-12. Comparison of pilot comments and ratings with some of the classical handling qualities criteria for transport aircraft provided information on the usefulness of these criteria and insight into supersonic flying qualities issues. A second research study has recently been completed which again addressed supersonic flying qualities issues through evaluations of the SR-71 in flight at Mach 3. Additional insight into supersonic flying qualities issues was obtained through pilot ratings and comments. These ratings were compared with existing military specifications and proposed criteria for the High Speed Civil Transport. This paper investigates the disparity between pilot comments and the Neal/Smith criteria through a modification of the technique using vertical speed at the pilot station. The paper specifically addresses the pilot ability to control flightpath and pitch attitude in supersonic flight and pilot displays typical of supersonic maneuvering.

  5. Immunity-based detection, identification, and evaluation of aircraft sub-system failures

    NASA Astrophysics Data System (ADS)

    Moncayo, Hever Y.

    This thesis describes the design, development, and flight-simulation testing of an integrated Artificial Immune System (AIS) for detection, identification, and evaluation of a wide variety of sensor, actuator, propulsion, and structural failures/damages including the prediction of the achievable states and other limitations on performance and handling qualities. The AIS scheme achieves high detection rate and low number of false alarms for all the failure categories considered. Data collected using a motion-based flight simulator are used to define the self for an extended sub-region of the flight envelope. The NASA IFCS F-15 research aircraft model is used and represents a supersonic fighter which include model following adaptive control laws based on non-linear dynamic inversion and artificial neural network augmentation. The flight simulation tests are designed to analyze and demonstrate the performance of the immunity-based aircraft failure detection, identification and evaluation (FDIE) scheme. A general robustness analysis is also presented by determining the achievable limits for a desired performance in the presence of atmospheric perturbations. For the purpose of this work, the integrated AIS scheme is implemented based on three main components. The first component performs the detection when one of the considered failures is present in the system. The second component consists in the identification of the failure category and the classification according to the failed element. During the third phase a general evaluation of the failure is performed with the estimation of the magnitude/severity of the failure and the prediction of its effect on reducing the flight envelope of the aircraft system. Solutions and alternatives to specific design issues of the AIS scheme, such as data clustering and empty space optimization, data fusion and duplication removal, definition of features, dimensionality reduction, and selection of cluster/detector shape are also

  6. Canada's first fixed-site aircraft noise monitoring system

    SciTech Connect

    Standen, N.M.

    1982-01-01

    The nature of aircraft noise management in Canada as it is presently evolving is discussed. The population of aircraft operating in Canada is similar to most western nations with regard to aircraft type. Canada's airport system includes major airports owned and operated by the federal Department of Transport (Transport Canada), airports owned and operated by provinces, municipalities or local commissions, and privately owned and operated airports, largely catering to general aviation. In addition, there are airports which are owned by Transport Canada, but operated by another agency. The consequence of this arrangement is that the major jet transport traffic is handled by airports which are owned and operated by either Transport Canada or another government agency.

  7. AIRTV: Broadband Direct to Aircraft

    NASA Astrophysics Data System (ADS)

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

    2002-01-01

    over the poles. The system consists of a constellation of 4 geostationary satellites covering the earth and delivering its signals to the aircraft at S band (2.52 -2.67 GHz). The S-band spectrum is ideal for this application since it is allocated on a primary basis by the ITU for global broadcast service. The AirTV service is expected to begin in 2004 and should be unencumbered by adjacent satellite interference due to near completion of the ITU coordination process. Each satellite will deliver four 20 Mbps QPSK data streams consisting of multiplexed compressed digital video channels and IP data over the full global beam coverage. The 80 Mbps capacity of each satellite will provide approximately 60 video channels while still allocating 40 Mbits to data services. The combined constellation capacity of 320 Mbits will significantly exceed the capacity of any similar existing or currently planned global satellite system. In addition, the simplicity of the 4-satellite approach is the most cost effective means to deliver high bandwidth globally. Return links, which are required for internet service, will be provided through the existing Inmarsat Aero-H system already onboard virtually all long haul aircraft and will provide return data rates from the aircraft as high as 432 kbps. integrated receiver/decoder (IRD) assembly. The phased array antenna, a key technology element, is being developed by AirTV's strategic partner, CMC Electronics. This antenna is a scaled version of CMC's Inmarsat Aero H antenna and is capable of scanning to 5 degrees above the horizon. Wide angle scanning up to 85 degrees from zenith is necessary for aircraft traversing the northernmost latitudes on transoceanic routes. AirTV has designed both the satellite coverage and aircraft antenna performance to ensure that high signal quality is maintained along all non-polar airline routes. AirTV will be the future of aeronautical broadband delivery. It has been designed specifically for global services and

  8. Transfer Area Mechanical Handling Calculation

    SciTech Connect

    B. Dianda

    2004-06-23

    This calculation is intended to support the License Application (LA) submittal of December 2004, in accordance with the directive given by DOE correspondence received on the 27th of January 2004 entitled: ''Authorization for Bechtel SAX Company L.L. C. to Include a Bare Fuel Handling Facility and Increased Aging Capacity in the License Application, Contract Number DE-AC28-01R W12101'' (Arthur, W.J., I11 2004). This correspondence was appended by further Correspondence received on the 19th of February 2004 entitled: ''Technical Direction to Bechtel SAIC Company L.L. C. for Surface Facility Improvements, Contract Number DE-AC28-OIRW12101; TDL No. 04-024'' (BSC 2004a). These documents give the authorization for a Fuel Handling Facility to be included in the baseline. The purpose of this calculation is to establish preliminary bounding equipment envelopes and weights for the Fuel Handling Facility (FHF) transfer areas equipment. This calculation provides preliminary information only to support development of facility layouts and preliminary load calculations. The limitations of this preliminary calculation lie within the assumptions of section 5 , as this calculation is part of an evolutionary design process. It is intended that this calculation is superseded as the design advances to reflect information necessary to support License Application. The design choices outlined within this calculation represent a demonstration of feasibility and may or may not be included in the completed design. This calculation provides preliminary weight, dimensional envelope, and equipment position in building for the purposes of defining interface variables. This calculation identifies and sizes major equipment and assemblies that dictate overall equipment dimensions and facility interfaces. Sizing of components is based on the selection of commercially available products, where applicable. This is not a specific recommendation for the future use of these components or their related

  9. Multispectral imaging of aircraft exhaust

    NASA Astrophysics Data System (ADS)

    Berkson, Emily E.; Messinger, David W.

    2016-05-01

    Aircraft pollutants emitted during the landing-takeoff (LTO) cycle have significant effects on the local air quality surrounding airports. There are currently no inexpensive, portable, and unobtrusive sensors to quantify the amount of pollutants emitted from aircraft engines throughout the LTO cycle or to monitor the spatial-temporal extent of the exhaust plume. We seek to thoroughly characterize the unburned hydrocarbon (UHC) emissions from jet engine plumes and to design a portable imaging system to remotely quantify the emitted UHCs and temporally track the distribution of the plume. This paper shows results from the radiometric modeling of a jet engine exhaust plume and describes a prototype long-wave infrared imaging system capable of meeting the above requirements. The plume was modeled with vegetation and sky backgrounds, and filters were selected to maximize the detectivity of the plume. Initial calculations yield a look-up chart, which relates the minimum amount of emitted UHCs required to detect the presence of a plume to the noise-equivalent radiance of a system. Future work will aim to deploy the prototype imaging system at the Greater Rochester International Airport to assess the applicability of the system on a national scale. This project will help monitor the local pollution surrounding airports and allow better-informed decision-making regarding emission caps and pollution bylaws.

  10. The use of hydrogen for aircraft propulsion in view of the fuel crisis.

    NASA Technical Reports Server (NTRS)

    Weiss, S.

    1973-01-01

    In view of projected decreases in available petroleum fuels, interest has been generated in exploiting the potential of liquid hydrogen (LH2) as an aircraft fuel. Cost studies of LH2 production show it to be more expensive than presently used fuels. Regardless of cost considerations, LH2 is viewed as an attractive aircraft fuel because of the potential performance benefits it offers. Accompanying these benefits, however, are many new problems associated with aircraft design and operations; for example, problems related to fuel system design and the handling of LH2 during ground servicing. Some of the factors influencing LH2 fuel tank design, pumping, heat exchange, and flow regulation are discussed.

  11. Piloting considerations for terminal area operations of civil tiltwing and tiltrotor aircraft

    NASA Technical Reports Server (NTRS)

    Hindson, William S.; Hardy, Gordon H.; Tucker, George E.; Decker, William A.

    1993-01-01

    The existing body of research to investigate airworthiness, performance, handling, and operational requirements for STOL and V/STOL aircraft was reviewed for its applicability to the tiltrotor and tiltwing design concepts. The objective of this study was to help determine the needs for developing civil certification criteria for these aircraft concepts. Piloting tasks that were considered included configuration and thrust vector management, glidepath control, deceleration to hover, and engine failure procedures. Flight control and cockpit display systems that have been found necessary to exploit the low-speed operating characteristics of these aircraft are described, and beneficial future developments are proposed.

  12. CANISTER HANDLING FACILITY DESCRIPTION DOCUMENT

    SciTech Connect

    J.F. Beesley

    2005-04-21

    The purpose of this facility description document (FDD) is to establish requirements and associated bases that drive the design of the Canister Handling Facility (CHF), which will allow the design effort to proceed to license application. This FDD will be revised at strategic points as the design matures. This FDD identifies the requirements and describes the facility design, as it currently exists, with emphasis on attributes of the design provided to meet the requirements. This FDD is an engineering tool for design control; accordingly, the primary audience and users are design engineers. This FDD is part of an iterative design process. It leads the design process with regard to the flowdown of upper tier requirements onto the facility. Knowledge of these requirements is essential in performing the design process. The FDD follows the design with regard to the description of the facility. The description provided in this FDD reflects the current results of the design process.

  13. EXTREME -- Handling extreme data sets

    NASA Astrophysics Data System (ADS)

    Taylor, Mark

    This package provides some utilities, background documentation, and associated files for adapting the Starlink Software Collection, and software which uses it, to handle very large data sets. The principal focus of this is to move to use of 64 bits of address space on 64-bit operating systems. This document (SSN/73) is squarely aimed at the problem of adapting the Starlink Software Collection, and consequently focuses on the three operating systems (Solaris, Linux and Tru64) supported by Starlink, the compiled languages Fortran 77 and ANSI C, and Starlink's somewhat idiosyncratic build mechanisms. However, some of the discussion here may be of interest or use to people who are considering the change from 32 to 64 bits for software in other contexts.

  14. High altitude reconnaissance aircraft

    NASA Technical Reports Server (NTRS)

    Yazdo, Renee Anna; Moller, David

    1990-01-01

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

  15. Identification of Aircraft Hazards

    SciTech Connect

    K. Ashley

    2006-12-08

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

  16. IDENTIFICATION OF AIRCRAFT HAZARDS

    SciTech Connect

    K.L. Ashley

    2005-03-23

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

  17. Aircraft noise synthesis system

    NASA Astrophysics Data System (ADS)

    McCurdy, David A.; Grandle, Robert E.

    1987-02-01

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

  18. Aircraft noise synthesis system

    NASA Technical Reports Server (NTRS)

    Mccurdy, David A.; Grandle, Robert E.

    1987-01-01

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

  19. Aircraft Operations Classification System

    NASA Technical Reports Server (NTRS)

    Harlow, Charles; Zhu, Weihong

    2001-01-01

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

  20. Integrated Payload Data Handling Demonstrator

    NASA Astrophysics Data System (ADS)

    FitzGeorge, T.; Wishart, A.; Hann, M.; Phan, N.; Carr, C. M.; Cupido, E.; Fox, P.; Oddy, T.; McGregor, A.; Marshall, A.; Waltham, N.

    2013-09-01

    An integrated Payload Data Handling System (IPDHS) is one in which multiple instruments share a central payload processor for their on-board data processing tasks. This offers a number of advantages over the conventional decentralised architecture. Savings in payload mass and power can be realised because the total processing resource is matched to the requirement, as opposed to the decentralised architecture where the processing resource is in effect the sum of all the applications. Overall development cost can be reduced using a common processor. At individual instrument level the potential benefits include a standardised application development environment, and the opportunity to run the instrument data handling application on a fully redundant and more powerful processor. This paper describes a joint programme by Astrium Ltd, SCISYS UK Limited, Imperial College London and RAL Space to implement a realistic demonstration of an I-PDHS using engineering models of flight instruments (a magnetometer and a camera) and a laboratory demonstrator of a central payload processor which is functionally representative of a flight design. The objective is to raise the Technology Readiness Level (TRL) of the centralised data processing technique by addressing the key areas of task partitioning to prevent fault propagation and the use of a common development process for the instrument applications. The project is supported by a UK Space Agency grant awarded under the National Space Technology Programme SpaceCITI scheme. The demonstration system is set up at the UK Space Agency's International Space Innovation Centre (ISIC) at Harwell and makes use of the ISIC Concurrent Design Facility (CDF).