Engineering Papers⌕ Search

SEARCH · Engineering Papers

Results for “Test Pilots”

Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 721 records · Page 40
All sourcesNASA NTRSDOE OSTI
NASA NTRS2010

Heat Flux and Wall Temperature Estimates for the NASA Langley HIFiRE Direct Connect Rig

An objective of the Hypersonic International Flight Research Experimentation (HIFiRE) Program Flight 2 is to provide validation data for high enthalpy scramjet prediction tools through a single flight test and accompanying ground tests of the HIFiRE Direct Connect Rig (HDCR) tested in the NASA LaRC Arc Heated Scramjet Test Facility (AHSTF). The HDCR is a full-scale, copper heat sink structure designed to simulate the isolator entrance conditions and isolator, pilot, and combustor section of the HIFiRE flight test experiment flowpath and is fully instrumented to assess combustion performance over a range of operating conditions simulating flight from Mach 5.5 to 8.5 and for various fueling schemes. As part of the instrumentation package, temperature and heat flux sensors were provided along the flowpath surface and also imbedded in the structure. The purpose of this paper is to demonstrate that the surface heat flux and wall temperature of the Zirconia coated copper wall can be obtained with a water-cooled heat flux gage and a sub-surface temperature measurement. An algorithm was developed which used these two measurements to reconstruct the surface conditions along the flowpath. Determinations of the surface conditions of the Zirconia coating were conducted for a variety of conditions.

Cuda, Vincent, Jr.↗
NASA NTRS2013

Pre-Study Walkthrough with a Commercial Pilot for a Preliminary Single Pilot Operations Experiment

The number of crew members in commercial flights has decreased to two members, down from the five-member crew required 50 years ago. One question of interest is whether the crew should be reduced to one pilot. In order to determine the critical factors involved in safely transitioning to a single pilot, research must examine whether any performance deficits arise with the loss of a crew member. With a concrete understanding of the cognitive and behavioral role of a co-pilot, aeronautical technologies and procedures can be developed that make up for the removal of the second aircrew member. The current project describes a pre-study walkthrough process that can be used to help in the development of scenarios for testing future concepts and technologies for single pilot operations. Qualitative information regarding the tasks performed by the pilots can be extracted with this technique and adapted for future investigations of single pilot operations.

Single Pilot Operations↗
NASA NTRS1973

A technique for measuring hypersonic flow velocity profiles

A technique for measuring hypersonic flow velocity profiles is described. This technique utilizes an arc-discharge-electron-beam system to produce a luminous disturbance in the flow. The time of flight of this disturbance was measured. Experimental tests were conducted in the Langley pilot model expansion tube. The measured velocities were of the order of 6000 m/sec over a free-stream density range from 0.000196 to 0.00186 kg/cu m. The fractional error in the velocity measurements was less than 5 percent. Long arc discharge columns (0.356 m) were generated under hypersonic flow conditions in the expansion-tube modified to operate as an expansion tunnel.

Gartrell, L. R.↗
NASA NTRS1973

Free-stream temperature, density, and pressure measurements in an expansion tube flow

An experimental study was conducted to determine test-flow conditions in the Langley pilot model expansion tube. Measurements of temperature, density, wall pressure, pitot pressure, and shock and interface velocities were compared with theoretical calculations based on various models of the flow cycle. The vibrational temperature and integrated density of the molecular oxygen component of the flow were measured by use of vacuum ultraviolet absorption techniques. These measurements indicate both the presence and possible degree of nonequilibrium in the flow. Data are compared with several simplified models of the flow cycle, and data trends are discussed.

Haggard, K. V.↗
NASA NTRS1974

Investigation of an anomalous flow condition of the Langley pilot model expansion tube

Free-stream flow velocity measurements were made in the Langley pilot model expansion tube during the test flow interval. During this interval, an anomalous dip in pitot pressure occurs for the expansion tube operating conditions employed. Within the test flow interval, the main conclusions reached from comparison of the measured flow velocity, pitot pressure, and tube wall pressure are: the variations which occur in velocity and wall pressure are small compared with the variations in pitot pressure; a corresponding dip in the derived flow density is associated with the dip in pitot pressure; and the value of the average density over the interval, which results from the expansion from the shocked intermediate chamber condition, is approximately one-half of the value that can result from only an isentropic process.

Friesen, W. J.↗
NASA NTRS1981

Diversity techniques for omnidirectional telemetry coverage of the HiMAT research vehicle

The highly maneuverable aircraft technology (HiMAT) remotely piloted research vehicle (RPRV) was flight tested and a number of technological advances applicable to future fighter aircraft were demonstrated. The aircraft control system uses airborne and ground-based computers which communicate via uplink and downlink telemetry. Antenna radiation patterns are normally much less than ideal for continuous reception or transmission for all aircraft attitudes. After flight qualification and testing on other aircraft, a frequency diversity concept and an antenna diversity concept were implemented on the HiMAT vehicle to obtain omnidirectional telemetry coverage.

Harney, P. F.↗
NASA NTRS1980

HiMAT systems development results and projections

Significant findings of the Highly Maneuverable Aircraft Technology Remotely Piloted Research Vehicle (HiMAT RPRV) flight test program are presented. Among the topics covered are: aerodynamic scaling relationships, the aeroelastic tailoring of wing and canard twist and camber, and laminate graphite/epoxy composite primary structure performance under high-g loading maneuvers. Attention is also given to the set of actuators used in the test and development program, with a view to the minimization of costs through modularity and interchangeability of components and the extensive use of off-the-shelf equipment. The relationship between composite ply geometry and the shape and magnitude of aeroelastic deformations during maneuvering is discussed in detail.

Brown, L. E., Jr.↗
NASA NTRS1982

NASA/FAA Helicopter ATC simulation investigation of RNAV/MLS instrument approaches

The NASA/FAA Helicopter Air Traffic Control (ATC) simulation investigations to determine the feasibility of simultaneous, independent instrument approach procedures for helicopters at major terminal areas, using Area Navigation/Microwave Landing System (RNAV/MLS) guidance, was conducted at several levels of helicopter display sophistication, up to that of a Cockpit Display of Traffic Information (CDTI) system. Test objectives included the determination of pilot acceptability and the tracking performance of the RNAV/MLS's noninterfering rotorcraft approach path structure, along with the evaluation of the effect on controller workload of multiroute structures combining conventional and rotorcraft approaches at various arrival rates and traffic separations. The utility of electronic area maps and CDTI displays was also investigated. Participating pilots flew 127 simulated instrument approaches in an ATC simulation laboratory.

Peach, L. L., Jr.↗
NASA NTRS1986

CID overview

On December 1, 1984, NASA and the Federal Aviation Administration (FAA) conducted the first remotely piloted air-to-ground crash test of a transport category aircraft. The Full-Scale Transport Controlled Impact Demonstration (CID) was the culmination of 4 years of effort by the two agencies. NASA and the FAA had many objectives during the joint planning and execution of the Controlled Impact Demonstration. The structural loads experiment was very successful. Ninety-seven percent of the channels were active at impact. The data is still being assessed. Only a portion of the data is presented here; approximately 80 channels of data are available. Analysis of the remaining data is in progress. Interior photography was also very successful. One hundred percent of the cameras functioned. The film contains unique information on the development of fire and smoke in the interior of the aircraft. From a human tolerance point of view, the CID was simulation of a survivable crash.

Hayduk, R. J.↗
NASA NTRS1984

Highly Maneuverable Aircraft Technology (HiMAT) flight-flutter test program

The highly maneuverable aircraft technology (HiMAT) vehicle was evaluated in a joint NASA and Air Force flight test program. The HiMAT vehicle is a remotely piloted research vehicle. Its design incorporates the use of advanced composite materials in the wings, and canards for aeroelastic tailoring. A flight-flutter test program was conducted to clear a sufficient flight envelope to allow for performance, stability and control, and loads testing. Testing was accomplished with and without flight control-surface dampers. Flutter clearance of the vehicle indicated satisfactory damping and damping trends for the structural modes of the HiMAT vehicle. The data presented include frequency and damping plotted as a function of Mach number.

Kehoe, M. W.↗
NASA NTRS1986

Impact data from a transport aircraft during a controlled impact demonstration

On December 1, 1984, the FAA and NASA conducted a remotely piloted air-to-ground crash test of a Boeing 720 transport aircraft instrumented to measure crash loads of the structure and the anthropomorphic dummy passengers. Over 330 time histories of accelerations and loads collected during the Full-Scale Transport Controlled Impact Demonstration (CID) for the 1-sec period after initial impact are presented. Although a symmetric 1 deg. nose-up attitude with a 17 ft/sec sink rate was planned, the plane was yawed and rolled 13 deg. at initial (left-wing) impact. The first fuselage impact occurred near the nose wheel well with the nose pitched down 2.5 deg. Peak normal (vertical) floor accelerations were highest in the cockpit and forward cabin near the nose wheel well and were approximately 14G. The remaining cabin floor received normal acceleration peaks of 7G or less. The peak longitudinal floor accelerations showed a similar distribution, with the highest (7G) in the cockpit and forward cabin, decreasing to 4G or less toward the rear. Peak transverse floor accelerations ranged from about 5G in the cockpit to 1G in the aft fuselage.

Fasanella, E. L.↗
NASA NTRS1991

Perceptual style and tracking performance

The relationship between perceptual style and tracking of a target was examined. Four pilots were given the Embedded Figures Test to assess their degrees of field dependence or independence. Then they flew in a helicopter simulator and attempted to track an airborne target. A high negative correlation was found between perceptual style and tracking performance. Field-independent subjects were able to track the target for longer periods than field-dependent subjects.

Atchley, Paul↗
NASA NTRS1991

Controls for agility research in the NASA High-Alpha Technology Program

The research process being used to develop control law design methodologies and guidelines in the NASA High-Alpha Technology Program are discussed. This step-by-step process consists of four basic elements: (1) control law architecture definition and linear synthesis, (2) nonlinear batch simulation, (3) piloted simulation evaluation, and (4) flight test validation. This paper discusses the research tools being used in this effort and provides a status report on design methodologies and guidelines being developed for each of these elements.

Foster, John V.↗
NASA NTRS1993

Effects of compression and expansion ramp fuel injector configuration on scramjet combustion and heat transfer

A scramjet combustor with four wall-ramp injectors containing Mach-1.7 fuel jets in the base of the ramps was investigated experimentally. During the test program, two swept ramp injector designs were evaluated. One swept-ramp model had 10-deg compression-ramps and the other had 10-deg expansion cavities between flush wall ramps. The scramjet combustor model was instrumented with pressure taps and heat-flux gages. The pressure measurements indicated that both injector configurations were effective in promoting mixing and combustion. Autoignition occurred for the compression-ramp injectors, and the fuel began to burn immediately downstream of the injectors. In tests of the expansion ramps, a pilot was required to ignite the fuel, and the fuel did not burn for a distance of at least two gaps downstream of the injectors. Once initiated, combustion was rapid in this configuration. Heat transfer measurements showed that the heat flux differed greatly both across the width of the combustor and along the length of the combustor.

Stouffer, Scott D.↗