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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 703 records · Page 39
All sourcesNASA NTRSDOE OSTI
NASA NTRS1973

Results of tests in the MSFC 14 x 14 inch trisonic wind tunnel on a .004 scale model of the Rockwell International Space Shuttle Vehicle 3, (integrated configuration)

Experimental aerodynamic investigations were conducted during mid-July, 1973 on a .004 scale model of the Rockwell International integrated configuration Space Shuttle Vehicle 3. The purpose of the tests was three fold: (1) to determine the static stability characteristics of the integrated vehicle, utilizing the Vehicle 3 orbiter configuration; (2) to determine the effect of interstage structure and tank external fuel lines on the integrated vehicle aerodynamic characteristics; (3) to determine the effects of the aft interstage structure on orbiter aerodynamic loads. Data were recorded on the integrated vehicle (test no. 579) at angles of attack and sideslip ranging from -10 deg to 10 deg over a Mach number schedule from 0.6 to 4.96. Data were obtained on the orbiter alone in the presence of the external tank with SRB attached (test no. 580) at angles of attack from -10 deg to 10 deg over a Mach number range from .6 to 1.96. Plotted data are presented in the body axis system.

Allen, E. C.↗
NASA NTRS1973

Effects of the air breathing propulsion system on space shuttle orbiter subsonic stability and control characteristics (OA71A)

Experimental aerodynamic investigations were conducted on an 0.0405 scale representation of the -89B (2A) Space Shuttle Orbiter in a 7.75 x 11.00 ft low speed wind tunnel during the time period from July 27, 1973 to August 3, 1973. The primary test objective was to investigate the aerodynamic effects of engine nacelle grouping and location on the orbiter ferry mission configuration. Five nacelles were tested, both individually mounted as well as mounted in a podded configuration, at the baseline position and moved 45.0 in. aft (full scale). Orbiter control effectiveness, both with and without nacelles, was recorded at elevon deflections of 0 deg, 5 deg, 10 deg, -10 deg and -20 deg and aileron deflections, about 0 deg elevon, of 0 deg, 5 deg, 10 deg, and 15 deg. The model was sting mounted on a 2.5 inch diameter internal strain gage balance entering through the base region. The nominal angle of attack range was -4 deg or = alpha or = 30 deg. Yaw polars were recorded over the beta range of -10 deg or = beta or = at fixed angles of attack of 0 deg and 10 deg.

Mennell, R. C.↗
NASA NTRS1974

Design of a powered elevator control system

The design, fabrication and flight testing of a powered elevator system for the Augmentor Wing Jet STOL Research Aircraft (AWJSRA or Mod C-8A) are discussed. The system replaces a manual spring tab elevator control system that was unsatisfactory in the STOL flight regime. Pitch control in the AWJSRA is by means of a single elevator control surface. The elevator is used for both maneuver and trim control as the stabilizer is fixed. A fully powered, irreversible flight control system powered by dual hydraulic sources was designed. The existing control columns and single mechanical cable system of the AWJSRA have been retained as has been the basic elevator surface, except that the elevator spring tab is modified into a geared balance tab. The control surface is directly actuated by a dual tandem moving body actuator. Control signals are transmitted from the elevator aft quadrant to the actuator by a linkage system that includes a limited authority series servo actuator.

Glende, W. L. B.↗
NASA NTRS1973

Acoustic characteristics of a large-scale wind tunnel model of an upper-surface blown flap transport having two engines

The upper-surface blown (USB) flap as a powered-lift concept has evolved because of the potential acoustic shielding provided when turbofan engines are installed on a wing upper surface. The results from a wind tunnel investigation of a large-scale USB model powered by two JT15D-1 turbofan engines are-presented. The effects of coanda flap extent and deflection, forward speed, and exhaust nozzle configuration were investigated. To determine the wing shielding the acoustics of a single engine nacelle removed from the model were also measured. Effective shielding occurred in the aft underwing quadrant. In the forward quadrant the shielding of the high frequency noise was counteracted by an increase in the lower frequency wing-exhaust interaction noise. The fuselage provided shielding of the opposite engine noise such that the difference between single and double engine operation was 1.5 PNdB under the wing. The effects of coanda flap deflection and extent, angle of attack, and forward speed were small. Forward speed reduced the perceived noise level (PNL) by reducing the wing-exhaust interaction noise.

Falarski, M. D.↗
NASA NTRS1973

Static stability and control effectiveness of models 12-0 and 34-0 of the vehicle 3 configuration, volume 2

Static stability and control effectiveness characteristics of two 0.004 scale models of the vehicle 3 configuration are presented. The components investigated consisted of a single aft body, vertical/rudder, OMS pods with two interchangeable wings, four interchangeable forward bodies, four trimmers, and a spoiler. The test was conducted in a 14 x 14 inch trisonic wind tunnel over a Mach number range from 0.6 to 4.96. Angles of attack from 0 to 60 degrees and angles of sideslip from -10 to 10 degrees at 0, 10, 20, 30, and 40 degrees angle of attack were tested. Elevon, body flap, and speed brake deflection composed the parametric considerations. No grit was placed on the models during the test. The lateral-directional characteristics are presented along with some additional longitudinal data.

Allen, E. C.↗
NASA NTRS1974

Results of wind tunnel tests at Mach 5 on the .004 scale model 2A configuration space shuttle to determine proximity effects and orbiter control effectiveness during orbiter/external tank abort separation (IAG)

Results from tests in the NASA/MSFC Trisonic Wind Tunnel on 0.004-Scale Orbiter and External Tank Force Models in Close Proximity (RTLS Abort Separation Conditions) are presented. The primary test objectives were to obtain data concerning proximity effects on the aerodynamic forces and moments experienced by Vehicle 2A Configuration Shuttle Orbiter and External Tank during an abort separation (Return to Launch Site) at a Mach number of 5. Additionally, data on orbiter control effectiveness during such an abort was obtained. Proximity effects were investigated for relative angles of incidence from minus 5 deg to plus 10 deg of the orbiter FRL with respect to the external tank centerline over a range of vertical and longitudinal displacements from the mated position to 2.5 tank diameters below and 3 tank diameters aft of the mated position.

Garton, W. P.↗
NASA NTRS1974

TF34 Quiet Nacelle nearfield acoustic test results

The results of the nearfield acoustic tests conducted on the TF34 Quiet Nacelle are presented. The high fan noise suppression levels being sought (26 PNdB reduction in aft noise) necessitated the use of an extensive system of special nearfield acoustic instrumentation to properly evaluate the suppression achieved. The design, operation, and test results from each of these nearfield acoustic instrumentation systems are presented.

Coward, W. E.↗
NASA NTRS1974

Reduced gravity fecal collector seat and urinal

A waste collection system for use in a reduced gravity including a seat having an opening centrally located with a pair of opposed depressed valleys on opposite sides of said opening for accommodating the ischial tuberosities of a user. The seat has contoured surfaces for providing support of the user's body and includes a prominent ridge towards the rear, which provides forward-aft positioning cue to the user. A curved recess is provided adjacent the forward portion of the seat for accommodating a tubular urinal having an enlarged open mouth.

Brown, J. W.↗
NASA NTRS1974

Low speed wind tunnel flow field results for JT8D refan engines on the Boeing 727-200

Low speed flow angularity results are presented showing flow direction at the nacelle locations on the Boeing 727-200. Flow angle probes (yawheads) were used for measurements at side and center inlet positions on the aft fuselage. A range of flap settings were tested with flap angles of 0 deg, 15 deg, and 40 deg selected for investigation.

Easterbrook, W. G.↗
NASA NTRS1974

Results of tests OA26 and IA16 in the NASA/ARC 3.5-foot hypersonic wind tunnel on an 0.015-scale model (36-OTS) of the space shuttle configuration 140A/B to obtain pressures for venting analysis

Tests were conducted, from November 15 to December 4, 1973, to obtain surface pressure data on an 0.015-scale replica of the Space Shuttle Vehicle 4. Data were obtained at Mach numbers of 5.3, 7.4, and 10.3, to support the venting analysis for both launch and entry conditions. These tests were the final tests in a series covering a Mach number range from 0.6 to 10.3. The model was instrumented with pressure orifices in the vicinity of the cargo bay door hinge and parting lines, and on the side of the fuselage at the crew compartment, and below the orbital maneuvering system pods at the aft compartment. The model was tested at angles of attack and sideslip consistent with expected divergencies from the nominal trajectory.

Spangler, R. H.↗
NASA NTRS1973

System design of the Pioneer Venus spacecraft. Volume 11: Launch vehicle utilization

A summary of the spacecraft descriptions; the probe bus, large probe, small probe, and orbiter is presented. The highlights on the designs of the Atlas/Centaur spacecraft as compared to the corresponding Thor/Delta spacecraft designs are contained. A comparison is made of the two Atlas/Centaur spacecraft for reference. The major differences are the replacement of the probes of the forward end of the probe bus with the mechanically despun antenna of the orbiter and the replacement of the bicone antenna on the aft end with the orbit insertion motor. The cross sections of the large and small probes are compared. The major features of each probe are described. The Thor/Delta and Atlas/Centaur designs for the probe bus and orbiter are analyzed. The usable spacecraft mass for the Atlas/Centaur is roughly twice that for the Thor/Delta if the Type I trajectory is assumed. It is somewhat less for the Type II trajectory in the designated launch years. This additional mass capability leads to cost savings in many areas which are described.

Varga, R. J.↗
NASA NTRS1974

Results of tests OA63 and IA29 on an 0.015 scale model of the space shuttle configuration 140 A/B in the NASA/ARC 6- by 6-foot transonic wind tunnel, volume 1

Tests were conducted in the NASA/ARC 6- by 6-foot transonic wind tunnel from September 12 to September 28, 1973 on an 0.015-scale model of the space shuttle configuration 140 A/B. Surface pressure data were obtained for the orbiter for both launch and entry configuration at Mach numbers from 0.6 to 2.0. The surface pressures were obtained in the vicinity of the cargo bay door hinge and parting lines, the side of the fuselage at the crew compartment and below the OMS pods at the aft compartment. Data were obtained at angles of attack and sideslip consistent with the expected divergencies along the nominal trajectory. These tests were first in a series of tests supporting the orbiter venting analysis. The series will include tests in three facilities covering a total Mach number range from 0.6 to 10.4.

Spangler, R. H.↗
NASA NTRS1974

Results of tests (OA64 and IA35) of an 0.015-scale model (36-OTS) of the space shuttle configuration 140A/B in the NASA/LaRC unitary plan wind tunnel

Supersonic aerodynamic tests were conducted in the NASA/LaRC Unitary Plan Wind Tunnel on a 0.015-scale model of the Space Shuttle Vehicle 4 configuration. Surface pressure data were obtained for both the launch (test IA35) and entry (test OA64) configurations at Mach numbers from 2.5 to 4.5. The surface pressure was measured in the vicinity of the cargo bay door hinge and parting lines and on the side of the fuselage at the crew compartment and below the OMS pods at the aft compartment. Data were obtained for angles of attack and sideslip consistent with the expected excursions about the nominal trajectory values at the test Mach numbers. These tests were a part of a test series supporting the orbiter venting analysis over a Mach number range from 0.6 to 10.4

Thornton, D. E.↗
NASA NTRS1974

Study of the single body yawed-wing aircraft concept

Areas relating to the development and improvement of the single-fuselage, yawed-wing transonic transport concept were investigated. These included: (1) developing an alternate configuration with a simplified engine installation;(2) determining a structural design speed placard that would allow the engine-airframe match for optimum airplane performance; and (3) conducting an aeroelastic stability and control analysis of the yawed-wing configuration with a flexible wing. A two-engine, single-fuselage, yawed-wing configuration was developed that achieved the Mach 1.2 design mission at 5560 km (3000 nmi) and payload of 18,140 kg (40,000 lb) with a gross weight of 217,700 kg (480,000 lb). This airplane was slightly heavier than the aft-integrated four-engine configuration that had been developed in a previous study. A modified structural design speed placard, which was determined, resulted in a 6% to 8% reduction in the gross weight of the yawed-wing configurations. The dynamic stability characteristics of the single-fuselage yawed-wing configuration were found to be very dependent on the magnitude of the pitch/roll coupling, the static longitudinal stability, and the dihedral effect.

Kulfan, R. M.↗
NASA NTRS1974

Space shuttle SRM interim contract, part 1

Essential studies and analyses required to integrate the SRM into the booster and overall space shuttle system. Emphasis was placed on the case, nozzle, insulation, and propellant components with resulting performance, weight, and structural load characteristics being generated. Effort conducted during the time period of this contract included studies, analyses, planning, and preliminary design activities. Technical requirements identified in the SRM Project Request for Proposal No. 8-1-4-94-98401 and Thiokol's proposed SRM design (designated Configuration 0) established the basis for this effort. The requirements were evaluated jointly with MSFC and altered where necessary to incorporate new information that evolved after issuance of the RFP and during the course of this interim contract. Revised water impact loads and load distributions were provided based on additional model test data and analytical effort conducted by NASA subsequent to the RFP release. Launch pad peaking loads into the SRM aft skirt were provided which also represented a change from RFP requirements. A modified SRM/External Tank (ET) attachment configuration with new structural load data was supplied by NASA, and direction was received to include a 2 percent inert weight contingency.

Source record↗
NASA NTRS1974

Results of tests to determine the aerodynamic characteristics of two potential aeromaneuvering orbit-to-orbit shuttle (AMOOS) vehicle configurations in the NASA-Ames 3.5 foot hypersonic wind tunnel

An aerodynamic wind tunnel investigation was conducted in the NASA-Ames Research Center (ARC) 3.5-foot hypersonic facility to provide data for use in obtaining experimental force and static stability characteristics of two potential aeromaneuvering orbit-to-orbit shuttle (AMOOS) vehicle configurations. The experimental data were compared with the aerodynamic characteristics estimated using Newtonian theory, thus establishing the usefulness of these predictions. The candidate AMOOS configurations selected for the wind tunnel tests were the AMOOS 5B and HB configurations. Two flap configurations were tested for each candidate - a forward or compression surface flap and an aft or expansion flap. Photographs and sketches of the two configurations with different control surfaces are shown. It was determined that Newtonian theory generally predicted the aerodynamics of the 5B configuration with acceptable accuracy for all expansion flap deflections and for compression flap deflections less than or equal to 10 degrees. Flow separation upstream of large compression flap deflections was detected from the experimental data.

Ketter, F. C., Jr.↗
NASA NTRS1974

Experimental evaluation of compliant surfaces at low speeds

An experimental study was devised to determine the profile drag on a subsonic wind tunnel model partially covered with various compliant surface materials. The model consisted of a large section of constant thickness bounded fore and aft by symmetric airfoil fairings. A flat rigid plate, the control surface, could be exchanged for four contiguous complaint panels. The flexible media generally consisted of thin polyvinylchloride membranes stretched to various tensions over trapped fluid cavities of air, water, or polyethelene oxide solution, or over dry or flooded open-celled polyurethane foams. On the basis of very accurate direct-force cell measurements, all configurations were found to yield profile drags equal to or slightly higher than that obtained for the conventional rigid surface case. The results indicate that the potential for practical drag-reducing applications will be limited to either high-density or high-speed flows where more sensible pressure perturbations occur.

Mcalister, K. W.↗
NASA NTRS1973

The Space Shuttle Main Engine

A reusable high-performance rocket engine intended for putting the Space Shuttle orbiter vehicle into earth orbit is described. Three such engines are clustered in the aft end of the orbiter stage. They burn in parallel with the solid-propellant boosters during the initial ascent phase and continue to burn after booster ejection until just prior to orbit insertion. The nominal burn time is roughly 10 min. Propulsion requirements demand maximum performance from liquid oxygen/hydrogen propellants with a minimum hardware weight. The engine design and the present progress made in the development of the engine are discussed.

Castenholz, P. D.↗