Search NASA⌕ Search

Engineering topics

Burley, James R., II

Publications and source records attributed to Burley, James R., II.

Holographic Helmet-Mounted Display Unit

Helmet-mounted display unit designed for use in testing innovative concepts for display of information to aircraft pilots. Operates in conjunction with computers generating graphical displays. Includes two ocular subunits containing miniature cathoderay tubes and optics providing 40 degrees vertical, 50 degrees horizontal field of view to each eye, with or without stereopsis. In future color application, each ocular subunit includes trichromatic holographic combiner tuned to red, green, and blue wavelengths of phosphors used in development of miniature color display devices.

Burley, James R., II↗

Concepts for conformal and body-axis attitude information for spatial awareness presented in a helmet-mounted display

A piloted simulation study has been conducted to evaluate two methods of presenting attitude information in a helmet-mounted display (HMD) for spatial awareness in a fighter airplane. One method, the body-axis concept, displayed the information relative to the body axis of the airplane. The quantitative results of this study favored the body-axis concept. Although no statistically significant differences were noted for either the pilots' understanding of roll attitude or target position, the pilots made pitch judgment errors three times more often with the conformal display. The subjective results showed the body-axis display did not cause attitude confusion, a prior concern with this display. In the posttest comments, the pilots overwhelmingly selected the body-axis display as the display of choice.

Jones, Denise R.↗

Pilot/Vehicle display development from simulation to flight

The Pilot Vehicle Interface Group, Cockpit Technology Branch, Flight Management Division, at the NASA Langley Research Center is developing display concepts for air combat in the next generation of highly maneuverable aircraft. The High-Alpha Technology Program, under which the research is being done, is involved in flight tests of many new control and display concepts on the High-Alpha Research Vehicle, a highly modified F-18 aircraft. In order to support display concept development through flight testing, a software/hardware system is being developed which will support each phase of the project with little or no software modifications, thus saving thousands of manhours in software development time. Simulation experiments are in progress now and flight tests are slated to begin in FY1994.

Dare, Alan R.↗

Evaluation of conformal and body-axis attitude information for spatial awareness

The traditional head-up display (HUD) used in most modern fighter aircraft presents attitude information that is both conformal to the outside world and aligned with the body-axis of the aircraft. The introduction of helmet-mounted display (HMD) technology into simulated and actual flight environments has introduced an interesting issue regarding the presentation of attitude information. This information can be presented conformally or relative to the aircraft's body-axis, but not both (except in the special case where the pilot's line of sight is directly matched with the aircraft's body-axis). The question addressed with this study was whether attitude information displayed in an HMD should be presented with respect to the real world (conformally) or to the aircraft's body-axis. To answer this, both conformal and body-axis attitude symbology were compared under simulated air combat situations. The results of this study indicated that the body-axis concept was a more effective HMD display. A detailed description of the flight task and results of this study will be presented.

Jones, Denise R.↗

Predictive nosepointing and flightpath displays for air-to-air combat

As part of the High-Angle-of-Attack Technology Program (HATP), two integrated pictorial displays have been developed for piloted simulation evaluations and, ultimately, for flight testing on board the F/A-18 High Alpha Research Vehicle (HARV). The first concept is a nosepointing display which illustrates the range of control the pilot has over the aircraft nose. The second concept is a predictive flightpath display that allows the pilot to see how his current control inputs will affect his aircraft's future position and orientation. The development of both display concepts will be discussed, as well as the results from a piloted simulation experiment in which pilots viewed the flightpath display in a wide-field-of-view Helmet-Mounted Display (HMD) while engaged in an air-combat situation.

Viken, Sally A.↗

Qualitative evaluation of a conformal velocity vector display for use at high angles-of-attack in fighter aircraft

A piloted simulation study was conducted to evaluate the utility of a display device designed to illustrate graphically and conformally the approximate location of a fighter aircraft's velocity vector. The display device consisted of two vertical rows of light emitting diodes (LED's) located toward the center of the cockpit instrument panel to each side of the control stick. The light strings provided a logical extension of the head up display (HUD) velocity vector symbol at flight path angles which exceeded the HUD field-of-view. Four test subjects flew a modified F/A-18 model with this display in an air-to-air engagement task against an equally capable opponent. Their responses to a questionnaire indicated that the conformal velocity vector information could not be used during the scenarios investigated due to the inability to visually track a target and view the lights simultaneously.

Jones, Denise R.↗

A full-color wide-field-of-view holographic helmet-mounted display for pilot/vehicle interface development and human factors studies

The application of advanced display concepts and helmet-mounted display (HMD) technology to air-to-air combat in highly maneuverable aircraft is discussed. The concepts considered include control authority, aircraft attitude, and energy maneuverability, and an HMD system designed for simulation studies is described. The human factors issues involved are addressed.

Burley, James R., II↗

Effect of empennage arrangement on single-engine nozzle/afterbody static pressures at transonic speeds

An investigation has been conducted in the Langley 16-Foot Transonic Tunnel to determine the effects on empennage arrangement on single-engine nozzle/afterbody static pressures. Tests were done at Mach numbers from 0.60 to 1.20, nozzle pressure ratios from 1.0 (jet off) to 8.0. and angles of attack from -3 to 9 deg (at jet off conditions), depending on Mach number. Three empennage arrangements (aft, staggered, and forward) were investigated. Extensive measurements were made of static pressure on the nozzle/afterbody in the vicinity of the tail surfaces.

Henderson, William P.↗

Effect of a trade between boattail angle and wedge size on the performance of a nonaxisymmetric wedge nozzle

An investigation was conducted in the Langley 16-Foot Transonic Tunnel to determine the effect of a boattail angle and wedge-size trade on the performance of nonaxisymmetric wedge nozzles installed on a generic twin-engine fighter aircraft model. Test data were obtained at static conditions and at Mach numbers from 0.60 to 1.25. Angle of attack was held constant at 0 deg. High-pressure air was used to simulate jet exhaust, and the nozzle pressure ratio was varied from 1.0 (jet off) to slightly over 15.0. For the configurations studied, the results indicate that wedge size can be reduced without affecting aeropropulsive performance.

Carson, George T., Jr.↗

Parametric Study of Afterbody/nozzle Drag on Twin Two-dimensional Convergent-divergent Nozzles at Mach Numbers from 0.60 to 1.20

An investigation has been conducted in the Langley 16-Foot Transonic Tunnel to determine the effects of upper and lower external nozzle flap geometry on the external afterbody/nozzle drag of nonaxisymmetric two-dimensional convergent-divergent exhaust nozzles having parallel external sidewalls installed on a generic twin-engine, fighter-aircraft model. Tests were conducted over a Mach number range from 0.60 to 1.20 and over an angle-of-attack range from -5 to 9 deg. Nozzle pressure ratio was varied from jet off (1.0) to approximately 10.0, depending on Mach number.

Pendergraft, Odis C., Jr.↗