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Scott, B. C.

Publications and source records attributed to Scott, B. C..

Ground-simulation investigations of VTOL airworthiness criteria for terminal-area operations

Several ground-based simulation experiments undertaken to investigate concerns related to tilt-rotor aircraft airworthiness were conducted. The experiments were conducted on the National Aeronautics and Space Administration (NASA) Ames Research Center's Vertical Motion Simulator, which permits simulation of a wide variety of aircraft with a high degree of fidelity of motion cueing. Variations in conversion/deceleration profile, type of augmentation or automation, level of display assistance, and meteorological conditions were considered in the course of the experiments. Certification pilots from the Federal Aviation Administration (FAA) and the Civil Aviation Authority (CAA) participated, in addition to NASA research pilots. The setup of these experiments on the simulator is summarized, and some of the results highlighted.

Lebacqz, J. V.↗

Controlling Transistor Temperature During Burn-In

Boiling refrigerant provides simple temperature control for newly manufactured power transistors. Heat-transfer liquid is Fluorinert FC-77 (or equivalent). Liquid boils at 100 degrees C, which is specified temperature at which transistor cases should be maintained during burn-in with this technique.

Scott, B. C.↗

Ground-simulation investigation of VTOL instrument flight rules airworthiness criteria

A two-part ground-simulation investigation of VTOL terminal-area operations, conducted as part of a joint NASA/FAA program to develop airworthiness criteria for this class of vehicle, is described. The baseline vehicle selected for the simulations was a generalized version of the XV-15 tilt-rotor mathematical model, which was modified to permit generic variations in forces or moments or both with power or configuration changes. Additionally, changes to wing area and rotor-blade chord were considered as a means of modifying the allowable thrust-angle versus speed relationships (the conversion corridor). The Vertical Motion Simulator at Ames Research Center was used in the experiment. Four engineering test pilots conducted over 200 piloted evaluations examining the influence of the experimental variables on their ability to perform terminal-area operations.

Lebacqz, J. V.↗

An Operational evaluation of head up displays for civil transport operations. NASA/FAA phase 3 report

The advantages and disadvantages of head-up displays (HUDs) in commercial jet transport approach and landing operations was evaluated. Ten airline captains currently qualified in the B-727 aircraft flew a series of instrument landing system (ILS) and nonprecision approaches in a motion base simulator using both a flight director HUD concept and a flightpath HUD concept as well as conventional head-down instruments under a variety of environmental and operational conditions to assess: (1) the potential benefits of these HUDs in airline operations; (2) problems which might be associated with their use; and (3) flight crew training requirements and flight crew operating procedures suitable for use with the HUDs. Results are presented in terms of objective simulator based performance measures, subject pilot opinion and rating data, and observer data.

Lauber, J. K.↗

A head-up display format for transport aircraft approach and landing

An electronic flight-guidance display format was designed for use in evaluations of the collimated head-up display concept applied to transport aircraft landing. In the design process of iterative evaluation and modification, some general principles, or guidelines, applicable to electronic flight displays were suggested. The usefulness of an indication of instantaneous inertial flightpath was clearly demonstrated. Evaluator pilot acceptance of the unfamiliar display concepts was very positive when careful attention was given to indoctrination and training.

Bray, R. S.↗

An evaluation of head-up displays in civil transport operations

To determine the advantages and disadvantages of head-up displays (HUD) in civil transport approach and landing operations, an operational evaluation was conducted on the flight simulator for advanced aircraft at Ames. A non-conformal HUD concept which contained raw data and Flight Director command information, and a conformal, flight path HUD concept was designed to permit terminal area maneuvering, intercept, final approach, flare, and landing operations. Twelve B-727 line pilots (Captains) flew a series of precision and non-precision approaches under a variety of environmental and operational conditions, including wind shear, turbulence and low ceilings and visibilities. A preliminary comparison of various system and pilot performance measures as a function of display type (Flight Director HUD, Flight Path HUD, or No HUD) indicates improvements in precision and accuracy of aircraft flight path control when using the HUDs. The results also demonstrated some potentially unique advantages of a flight path HUD during non-precision approaches.

Lauber, J. K.↗

A head-up display for low-visibility approach and landing

An electronic flight-guidance display format was designed for use in evaluations of the collimated head-up display concept in low-visibility landings of transport aircraft. In the design process of iterative evaluation and modification, some general principles, or guidelines, applicable to such flight displays were suggested. The usefulness of an indication of instantaneous inertial flightpath was clearly demonstrated, particularly in low-altitude transition to visual references. Evaluator pilot acceptance of the unfamiliar display concepts was very positive when careful attention was given to indoctrination and training.

Bray, R. S.↗

Tentative civil airworthiness flight criteria for powered-lift transports

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

Hynes, C. S.↗

A STOL airworthiness investigation using a simulation of a deflected slipstream transport. Volume 1: Summary of results and airworthiness implications

A simulator study of short takeoff and landing (STOL) aircraft was conducted using a model of a deflected slipstream transport aircraft. The subjects considered are: (1) the approach, (2) flare and landing, (3) go-around, and (4) takeoff phases of flight. The results are summarized and possible implications with regard to airworthiness criteria are discussed. A data base is provided for future STOL airworthiness requirements and a preliminary indication of potential problem areas is developed. Comparison of the simulation results with various proposed STOL criteria indicates significant deficiencies in many of these criteria.

Stapleford, R. L.↗

A STOL airworthiness investigation using a simulation of an augmentor wing transport. Volume 2: Simulation data and analysis

A simulator study of STOL airworthiness was conducted using a model of an augmentor wing transport. The approach, flare and landing, go-around, and takeoff phases of flight were investigated. The simulation and the data obtained are described. These data include performance measures, pilot commentary, and pilot ratings. A pilot/vehicle analysis of glide slope tracking and of the flare maneuver is included.

Heffley, R. K.↗

A STOL airworthiness investigation using a simulation of an augmentor wing transport. Volume 1: Summary of results and airworthiness implications

A simulator study of STOL airworthiness criteria was conducted using a model of an augmentor wing transport. The approach, flare and landing, go-around, and takeoff phases of flight were investigated. The results are summarized and possible implications with regard to airworthiness criteria are discussed. The results provide a data base for future STOL airworthiness requirements and a preliminary indication of potential problem areas. The results are also compared to the results from an earlier simulation of the Breguet 941S. Where possible, airworthiness criteria are proposed for consideration.

Stapleford, R. L.↗

Motion simulator study of longitudinal stability requirements for large delta wing transport airplanes during approach and landing with stability augmentation systems failed

A ground-based simulator investigation was conducted in preparation for and correlation with an-flight simulator program. The objective of these studies was to define minimum acceptable levels of static longitudinal stability for landing approach following stability augmentation systems failures. The airworthiness authorities are presently attempting to establish the requirements for civil transports with only the backup flight control system operating. Using a baseline configuration representative of a large delta wing transport, 20 different configurations, many representing negative static margins, were assessed by three research test pilots in 33 hours of piloted operation. Verification of the baseline model to be used in the TIFS experiment was provided by computed and piloted comparisons with a well-validated reference airplane simulation. Pilot comments and ratings are included, as well as preliminary tracking performance and workload data.

Snyder, C. T.↗