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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.

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At least 109 records · Page 6
All sourcesNASA NTRSDOE OSTI
NASA NTRS1973

Wind tunnel test of the 0.015-scale Rockwell International space shuttle vehicle orbiter in the Ames 6 by 6 foot supersonic wind tunnel

Experimental investigations were performed in a 6- by 6-Foot Supersonic wind tunnel on a 0.015-scale model of the Rockwell International space shuttle vehicle (SSV) 2A orbiter. The purpose of the test was to investigate the longitudinal and lateral-directional characteristics of the vehicle. In addition, hinge moments were measured on the rudder and elevons. Buffet onset was investigated using wing trailing edge pressures and a strain gauge instrumented panel mounted in the wing. The model was tested through a Mach range from 0.6 to 2.0 at a constant unit Reynolds number of 2.5 million. Pitch runs were made at angles of attack from minus 2 deg to +26 deg with beta = 0 deg and 5 deg; yaw runs were made in the range from minus 5 deg to 10 deg of sideslip at angles of attack of 0 deg and 10 deg. Static pressures were measured at the fuselage base and the trailing edges of the wing and rudder. Boundary layer transition was fixed for some runs using distributed roughness strips.

Milam, M. D.↗
NASA NTRS1973

Experimental investigations of an 0.0405 scale Space Shuttle Configuration 3 orbiter to determine subsonic stability characteristics. Volume 1: OA21A

Experimental aerodynamic investigations were conducted in a low speed wind tunnel from May 21 through June 4 and from June 18 through June 25, 1973 on a 0.0405 scale -139B model Space Shuttle Vehicle (SSV) orbiter. The purpose of the test was to investigate the longitudinal and lateral-directional subsonic aerodynamic characteristics of the proposed PRR Space Shuttle orbiter. Emphasis was placed on component buildup effects, elevon, rudder, body flaps, rudder flare effectiveness, and canard and speed brake development. Angles of attack from -4 deg. to 24 deg. and angles of sideslip of -10 deg. to 10 deg. were tested. Static pressures were recorded on the base. The aerodynamic force balance results are presented in plotted and tabular form.

Cameron, B. W.↗
NASA NTRS1974

Experimental investigations of an 0.0405 scale space shuttle configuration 3 orbiter to determine subsonic stability characteristics (OA21A/OA21B), volume 2

Aerodynamic investigations were conducted in a low speed wind tunnel from June 18 through June 25, 1973 on a 0.0405 scale -139B model Space Shuttle Vehicle orbiter. The purpose of the test was to investigate the longitudinal and lateral-directional subsonic aerodynamic characteristics of the proposed PRR Space Shuttle Orbiter. Emphasis was placed on component buildup effects, elevon, rudder, body flaps, rudder flare effectiveness, and canard and speed brake development. Angles of attack from -4 to 24 and angles of sideslip of -10 to 10 were tested. Static pressures were recorded on the base. The aerodynamic force balance results are presented in plotted and tabular form.

Cameron, B. W.↗
NASA NTRS1974

Supersonic tests of an 0.015 scale space shuttle mated vehicle model (67-OTS) in the LaRC UPWT to obtain aerodynamic force data (IA42A/B)

Wind tunnel tests were conducted of the NASA/Rockwell 0.015 scale configuration 4 mated space shuttle vehicle. Data were obtained for a range of Mach numbers from 1.60 to 4.63 and angles of attack from minus 10 degrees to plus 10 degrees. A complete model build-up was performed. Longitudinal and lateral directional stability and control data were obtained for the tank alone, tank plus solid rocket boosters, and mated configuration of tank plus orbiter plus solid rocket boosters. Single component rudder hinge moment data were obtained at rudder deflections of zero degrees and minus 20 degrees for each Mach number tested.

Hardin, R.↗
NASA NTRS1974

Investigation of space shuttle orbiter subsonic stability and control characteristics in the NAAL low speed wind tunnel (OA62B), volume 2

Experimental aerodynamic investigations were conducted on a sting-mounted 0.0405 scale representation of the 140A/B space shuttle orbiter in a 7.75 ft by 11 ft low speed wind tunnel during the period from November 14, 1973 to December 6, 1973. Establishment of basic longitudinal stability characteristics in and out of ground effect, and the establishment of lateral-directional stability characteristics in free air were the primary test objectives. The following effects and configurations were tested: (1) two dual podded nacelle configurations; (2) stability and control characteristics at nominal elevon deflections, rudder deflections, airleron deflections, rudder flare angles, and body flap deflections; (3) effects of various elevon and elevon/fuselage gaps on longitudinal stability and control; (4) pressures on the vertical tail at spanwise stations using pressure bugs; (5) aerodynamic force and moment data measured in the stability axis system by an internally mounted, six-component strain gage balance. For Vol. 1, see N74-32324.

Mennell, R.↗
NASA NTRS1974

Results of transonic wind tunnel tests on an 0.015-scale space shuttle mated vehicle model (67-ots) in the LaRC 8 foot TPT (IA41)

Wind tunnel tests were conducted to obtain aerodynamic force data for Mach numbers from 0.60 to 1.20. Data were obtained for an alpha range of -10 deg to +10 deg (beta = 0 deg beta = 5 deg) and beta range of -10 deg to +10 deg (alpha = 0 deg). Longitudinal and lateral-directional stability and control data were obtained for tank alone, tank plus SRB's, tank plus Orbiter, and mated configuration of tank + Orbiter + SRB's. Also, single-component rudder hinge moment data were obtained at rudder deflections of 0 and -20 deg for each Mach number tested. Plots of aerodynamic coefficients vs. Mach number are presented, using data from both test IA41 and tests LRC-UPWT-1056, 1073 (IA42A/B) for Mach numbers of 1.60 to 4.63. The model tested in IA42A/B was the same model as tested in IA41.

Hardin, R.↗
NASA NTRS1975

A study of pilot behavior during controlling the lateral directional motion of airplanes in turbulent air

The pilot behaviors controlling the lateral directional motion of airplanes in turbulent air have been investigated by using the pilot transfer function which has been obtained by the analysis of flight test data. The pilot uses the gains for the aileron manipulation proportionally to bank angle so as to minimize r.m.s. of bank angle. The pilot rudder manipulations are done proportionally to rolling velocity, yawing velocity, and yaw angle. Namely, the pilot carries out the cross control for the rudder.

Beppu, G.↗
NASA NTRS1975

Wind tunnel test of the 0.019 scale space shuttle integrated vehicle (model 14-OTS) in the CALSPAN 8-foot transonic wind tunnel (IA36), volume 2

A test is presented which was performed to determine the effect of cold jet gas plumes generated from main propulsion system and solid rocket motor nozzles on: (1) six-component force and moment data, (2) wing static pressures, (3) wing hinge moment, (4) elevon hinge moment, (5) rudder hinge moment, and (6) orbiter MPS nozzle pressure loads. The effects of rudder deflection, nozzle gimbal angle, and plume size were also obtained.

Hardin, R. B.↗
NASA NTRS1975

Results of an aerodynamic investigation of a space shuttle orbiter/747 carrier vehicle configuration to establish a free-stream data base for ALT separation investigations, utilizing a 0.0125-scale model (48-0/AX1318I-1) in the ARC 14-foot wind tunnel (CA23A)

Force and moment data are presented which were obtained for each vehicle separately at a Mach number of 0.6, and for the mated orbiter/747 configuration at Mach numbers of 0.3, 0.5, 0.6, and 0.7. Orbiter angles of attack from 0 degrees to +12 degrees and 747/Carrier angles of attack from -3 degrees to +7 degrees were investigated at angles of sideslip of 0 degrees and -5 degrees. Model variables include orbiter elevon and rudder deflections, orbiter tail cone-on and off, various orbiter/747 attach structure configurations, 747 stabilizer and rudder deflections, and 747 CAM modification components-on and off. Photographs of test configurations are included.

Gillins, R. L.↗
NASA NTRS1976

Simulator study of the effectiveness of an automatic control system designed to improve the high-angle-of-attack characteristics of a fighter airplane

A piloted, fixed-base simulation was conducted to study the effectiveness of some automatic control system features designed to improve the stability and control characteristics of fighter airplanes at high angles of attack. These features include an angle-of-attack limiter, a normal-acceleration limiter, an aileron-rudder interconnect, and a stability-axis yaw damper. The study was based on a current lightweight fighter prototype. The aerodynamic data used in the simulation were measured on a 0.15-scale model at low Reynolds number and low subsonic Mach number. The simulation was conducted on the Langley differential maneuvering simulator, and the evaluation involved representative combat maneuvering. Results of the investigation show the fully augmented airplane to be quite stable and maneuverable throughout the operational angle-of-attack range. The angle-of-attack/normal-acceleration limiting feature of the pitch control system is found to be a necessity to avoid angle-of-attack excursions at high angles of attack. The aileron-rudder interconnect system is shown to be very effective in making the airplane departure resistant while the stability-axis yaw damper provided improved high-angle-of-attack roll performance with a minimum of sideslip excursions.

Gilbert, W. P.↗
NASA NTRS1979

Spring control of wire harness loops

Negator spring control guides wire harness between movable and fixed structure. It prevents electrical wire harness loop from jamming or being severed as wire moves in response to changes in position of aircraft rudder. Spring-loaded coiled cable controls wire loop regardless of rudder movement.

Curcio, P. J.↗
NASA NTRS1980

Thrust augmented spin recovery device

Yaw control surfaces were developed for a jet propelled aircraft. A thrust augmented rudder is disposed above the jet exhaust stream and a thrust rudder tab extends downward into the jet exhaust stream. These components are cooperatively deflected to generate yawing moments for directional control of the aircraft.

Berrier, B. L.↗
NASA NTRS1982

Spin-tunnel investigation of a 1/13-scale model of the NASA AD-1 oblique-wing research aircraft

The spin and recovery characteristics of a 1/13-scale model of the NASA AD-1 oblique-wing research aircraft at wing-skew positions of 0, 25, 45, and 60 deg (right wing forward) were investigated. Spins were obtained for all wing-skew positions tested. For the unskewed wing position, two spin modes were possible. One spin mode was very steep and recoveries were obtained within 1 turn or less by rudder reversal. The second spin mode was flat and fast; the angle of attack was about 75 deg and the spin rate was about 145 deg/sec (2.5 seconds per turn). For the skewed wing positions, spins were obtained only in the direction of the forward-skewed wing (right wing forward). No spins were obtained to the left when the wing was skewed with the right wing forward. Recoveries should be attempted by deflecting the rudder to full against the spin, the ailerons to full with the spin, and movement of the wings to 0 deg skew. If the wing is skewed, the recovery may not be effected until the wing skew approaches 0 deg.

White, W. L.↗
NASA NTRS1982

Pilot opinions of sampling effects in lateral-directional control

Flight experiments with a microprocessor control system were conducted to determine the effects of variations in sampling parameters on several pilots' opinions of lateral-directional flying qualities. Princeton's variable-response research aircraft (VRA), which is equipped with a microprocessor based digital flight control system (Micro-DFCS), was the test vehicle. Two U.S. Navy pilots evaluated the effects of sampling rate, quantization, and pure time delay during tracking, approach, and landing. Aircraft carrier approach tasks were conducted using a Navy approach mirror. Acquisition and tracking of fixed objects on the ground provided additional information related to the Navy misson. The longitudinal controls were implemented with analog electronics, while the lateral-directional pilot inputs (stick and rudder) were fed to the Micro-DFCS, which commanded the ailerons and rudder. The conceptual relationship between the evaluation pilot's lateral-directional inputs, the flight computer, and the aircraft are illustrated.

Stengel, R. F.↗
NASA NTRS1983

Braking and cornering studies on an air cushion landing system

An experimental investigation was conducted to evaluate several concepts for braking and steering a vehicle equipped with an air cushion landing system (ACLS). The investigation made use of a modified airboat equipped with an ACLS. Braking concepts were characterized by the average deceleration of the vehicle. Reduced lobe flow and cavity venting braking concepts were evaluated in this program. The cavity venting braking concept demonstrated the best performance, producing decelerations on the test vehicle on the same order as moderate braking with conventional wheel brakes. Steering concepts were evaluated by recording the path taken while attempting to follow a prescribed maneuver. The steering concepts evaluated included using rudders only, using differential lobe flow, and using rudders combined with a lightly loaded, nonsteering center wheel. The latter concept proved to be the most accurate means of steering the vehicle on the ACLS, producing translational deviations two to three times higher than those from conventional nose-gear steering. However, this concept was still felt to provide reasonably precise steering control for the ACLS-equipped vehicle.

Daugherty, R. H.↗
NASA NTRS1983

Review of NASA ACLS research

An experimental investigation was conducted to evaluate a method of maintaining stability of an air cushion vehicle and also to evaluate several concepts to brake and steer an ACLS-equipped vehicle. The investigation used a modified airboat equipped with an air cushion landing system. The pressure relief door stability concept was characterized by the ACLS pressure time histories. The pressure relief doors vented excess cavity and lobe pressures and consistently maintained vehicle heave and pitch stability. Braking concepts were characterized by the average deceleration of the vehicle. Reduced lobe flow and cavity venting braking concepts were evaluated in this program. The cavity venting concept demonstrated the best performance, producing decelerations on the test vehicle on the same order as moderate braking with conventional wheel brakes. Steering concepts were evaluated by recording the path taken while attempting to follow a prescribed maneuver. The steering concepts evaluated included using rudders only, using differential lobe flow, and using rudders combined with a lightly loaded, nonsteering center wheel. The latter concept proved to be the most accurate means of steering the vehicle on the ACLS, producing translational deviations which, while two to three times higher than those from conventional nose gear steering, were still felt to provide reasonably precise steering control for this type vehicle.

Daugherty, R. H.↗
NASA NTRS1985

Space shuttle rudder/speedbrake actuation subsystem

The Rudder/Speedbrake (R/SB) Actuation Subsystem for use on the NASA Space Shuttle Orbiter is an electro-hydro-mechanical system which provides the control and positionary capability of the orbiter aero-dynamic primary flight control surface. The system is located in the vehicle's vertical stabilizer. The geared rotary actuators provide a power hinge feature of the split panel rudder. Actuation of both panels in the same direction provides conventional rudder control; actuating the panels differentially provides a speedbrake function intended to control both speed and pitch. The commands may be superimposed on one another. The system consists of one power drive unit which responds to quadredundant avionic signals to generate a rotary output, four geared rotary actuators, which develop rotary position and torque as outputs, and ten torque transmitting drive-shifts.

Naber, R. A.↗
NASA NTRS1985

Static investigation of several yaw vectoring concepts on nonaxisymmetric nozzles

A test has been conducted in the static test facility of the Langley 16-Foot Transonic Tunnel to determine the flow-turning capability and the effects on nozzle internal performance of several yaw vectoring concepts. Nonaxisymmetric convergent-divergent nozzles with throat areas simulating dry and afterburning power settings and single expansion ramp nozzles with a throat area simulating a dry power setting were modified for yaw thrust vectoring. Forward-thrust and pitch-vectored nozzle configurations were tested with each yaw vectoring concept. Four basic yaw vectoring concepts were investigated on the nonaxisymmetric convergent-divergent nozzles: (1) translating sidewall; (2) downstream (of throat) flaps; (3) upstream (of throat) port/flap; and (4) powered rudder. Selected combinations of the rudder with downstream flaps or upstream port/flap were also tested. A single yaw vectoring concept, post-exit flaps, was investigated on the single expansion ramp nozzles. All testing was conducted at static (no external flow) conditions and nozzle pressure ratios varied from 2.0 up to 10.0.

Mason, M. L.↗