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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 757 records · Page 42
All sourcesNASA NTRSDOE OSTI
NASA NTRS1976

Transonic-supersonic high Reynolds number stability and control characteristics of a 0.015-scale (remotely controlled elevon) model 44-0 of the space shuttle orbiter tested in the VSD high speed wind tunnel (LA67)

A detailed aerodynamic data base which can be used to substantiate the aerodynamic design data book for the current shuttle orbiter configuration was generated. Special attention was directed to definition of non-linear aerodynamic characteristics by taking data at small increments in the angle of attack, angle of sideslip, Mach number, and elevon position. Six-component aerodynamic force and moment and elevon position data were recorded over an angle-of-attack range from -2 deg to as high as 32 deg at angles of sideslip of 0 deg, 1 deg, and +2 deg. The test Mach numbers were 0.60, 0.80, 0.90, 1.2, 1.5, 2.0, 3.0, and 4.6. The effects of Reynolds number were investigated and covered a range from 5.0 to 16.0 million per foot.

Source record↗
NASA NTRS1977

Transonic high Reynolds number stability and control characteristics of a 0.015-scale remotely controlled elevon model (44-0) of the space shuttle orbiter tested in calspan 8-foot TWT (LA70)

Transonic Wind Tunnel tests were run on a .015 scale model of the space shuttle orbiter vehicle in the 8-foot transonic wind tunnel. Purpose of the test program was to obtain basic shuttle aerodynamic data through a full range of elevon and aileron deflections, verification of data obtained at other facilities, and effects of Reynolds number. Tests were performed at Mach numbers from .35 to 1.20 and Reynolds numbers from 3,500,000 to 8,200,000 per foot. The high Reynolds number conditions (nominal 8,000,000/foot) were obtained using the ejector augmentation system. Angle of attack was varied from -2 to +20 degrees at sideslip angles of -2, 0, and +2 degrees. Sideslip was varied from -6 to +8 degrees at constant angles of attack from 0 to +20 degrees. Aileron settings were varied from -5 to +10 degrees at elevon deflections of -10, 0, and +10 degrees. Fixed aileron settings of 0 and 2 degrees in combination with various fixed elevon settings between -20 and +5 degrees were also run at varying angles of attack.

Parrell, H.↗
NASA NTRS1976

Subsonic stability and control characteristics of a 0.015-scale (remotely controlled elevon) model 44-0 of the space shuttle orbiter tested in the NASA/ARC 12-foot pressure tunnel (LA66)

The investigation was conducted in the NASA/Ames Research Center 12-foot Pressure Tunnel. The model was a Langley-built 0.015-scale SSV orbiter model with remote independently operated left and right elevon surfaces. The objective of the test was to generate a detailed aerodynamic data base for the current shuttle orbiter configuration. Special attention was directed to definition of nonlinear aerodynamic characteristics by taking data at small increments in angle of attack, angle of sideslip, and elevon position. Six-component aerodynamic force and moment and elevon position data were recorded over an angle of attack range from -4 deg to 24 deg at angles of sideslip of 0 deg and + or - 4 deg. Additional tests were made over an angle of sideslip range from -6 deg to 6 deg at selected angles of attack. The test Mach numbers were 0.22 and 0.29 and the Reynolds number was varied from 2.0 to 8.5 million per foot.

Underwood, J. M.↗
NASA NTRS1976

Low-subsonic stability and control characteristics of a 0.015-scale remotely controlled elevon model (44-0) of the space shuttle orbiter in the Langley Research Center low turbulence pressure tunnel (LA61B)

A Langley-built 0.015-scale SSV orbiter configuration with remote independently operated left and right elevon surfaces was tested in the NASA/Langley Research Center Low Turbulence Pressure Tunnel. A detailed aerodynamic data base was obtained for the current shuttle orbiter configuration. Special attention was directed to definition of Reynolds number effects on nonlinear aerodynamic characteristics of the orbiter. Small increments in angle of attack, sideslip, and elevon/aileron position were studied in order to better define areas where nonlinearities may occur. Force and moment, and elevon position data were recorded over an angle of attack range -2 deg to 20 deg at angles of sideslip of 0 deg , + or - 2 deg, and + or - 4 deg. Tests were also made over an angle of sideslip range of -6 deg to 6 deg at selected angles of attack and elevon/aileron position. The test Mach numbers were from 0.15 to 0.30 at Reynolds numbers from 2.0 to 13.5 million per foot.

Source record↗
NASA NTRS1976

High supersonic stability and control characteristics of a 0.015-scale (remotely controlled elevon) model 44-0 space shuttle orbiter tested in the NASA/LaRC 4-foot UPWT (LEG 2) (LA75), volume 1

Wind tunnel tests are reported on a 0.015-scale SSV orbiter model with remote independently operated left and right elevon surfaces. Special attention was directed to definition of nonlinear aerodynamic characteristics by taking data at small increments. Six component aerodynamic force and moment and elevon position data were recorded for the space shuttle orbiter with various elevon, aileron rudder and speed brake deflection combinations over an angle of attack range from -4 deg to 32 deg at angles of sideslip of 0 deg and 3 deg. Additional tests were made over an angle of sideslip range from -6 deg to 8 deg at selected angles of attack. Test Mach numbers were 2.86, 2.90, 3.90 and 4.60 with Reynolds numbers held at a constant 2.0 x 1 million per foot.

Ball, J. W.↗
NASA NTRS1977

Generalized environmental control and life support system computer program (G189A) configuration control, phase 2

The G189A simulation of the Shuttle Orbiter ECLSS was upgraded. All simulation library versions and simulation models were converted from the EXEC2 to the EXEC8 computer system and a new program, G189PL, was added to the combination master program library. The program permits the post-plotting of up to 100 frames of plot data over any time interval of a G189 simulation run. The overlay structure of the G189A simulations were restructured for the purpose of conserving computer core requirements and minimizing run time requirements.

Mcenulty, R. E.↗
NASA NTRS1978

Elevation scanning laser/multi-sensor hazard detection system controller and mirror/mast speed control components

The electro-mechanical and electronic systems involved with pointing a laser beam from a roving vehicle along a desired vector are described. A rotating 8 sided mirror, driven by a phase-locked dc motor servo system, and monitored by a precision optical shaft encoder is used. This upper assembly is then rotated about an orthogonal axis to allow scanning into all 360 deg around the vehicle. This axis is also driven by a phase locked dc motor servo-system, and monitored with an optical shaft encoder. The electronics are realized in standard TTL integrated circuits with UV-erasable proms used to store desired coordinates of laser fire. Related topics such as the interface to the existing test vehicle are discussed.

Craig, J.↗
NASA NTRS1981

High frequency drive mechanism for an active controls systems aircraft control surface

The mechanism was successfully utilized on a wind tunnel model tested in the transonic blow down tunnel. The mechanism is also applicable to a flying aircraft. Several interrelated mechanical subsystems were utilized, including a low inertia antibacklash drive mechanism for high frequency oscillation and a compact antibacklash drive mechanism for conversion of rotary motion to linear motion.

Smith, H. E.↗
NASA NTRS1984

System design of a remotely operated, program controlled measurement table for the calibration of the Egret experiment. Part A: Program control

The structure of the program, the five priority levels, the drive routines, the stepwise drive plan, the figure routines, meander X and y, the range of measurement table, the optimization of figure drive, the figure drive plan, dialogue routines, stack processing, the drive for the main terminal, the protocol routines, the drive for the microterminal, the drive for the experiment computer, and the main program are discussed.

Source record↗
NASA NTRS1985

Description, validation, and modification of the Guyton model for space-flight applications. Part A. Guyton model of circulatory, fluid and electrolyte control. Part B. Modification of the Guyton model for circulatory, fluid and electrolyte control

The mathematical model that has been a cornerstone for the systems analysis of space-flight physiological studies is the Guyton model describing circulatory, fluid and electrolyte regulation. The model and the modifications that are made to permit simulation and analysis of the stress of weightlessness are described.

Leonard, J. I.↗
NASA NTRS1987

Space station control moment gyro control

The potential large center-of-pressure to center-of-gravity offset of the space station makes the short term, within an orbit, variations in density of primary importance. The large range of uncertainty in the prediction of solar activity will penalize the design, developments, and operation of the space station.

Bordano, Aldo↗