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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 1,531 records · Page 85
All sourcesNASA NTRSDOE OSTI
NASA NTRS1973

Space shuttle post-entry and landing analysis. Volume 2: Appendices

Four candidate navigation systems for the space shuttle orbiter approach and landing phase are evaluated in detail. These include three conventional navaid systems and a single-station one-way Doppler system. In each case, a Kalman filter is assumed to be mechanized in the onboard computer, blending the navaid data with IMU and altimeter data. Filter state dimensions ranging from 6 to 24 are involved in the candidate systems. Comprehensive truth models with state dimensions ranging from 63 to 82 are formulated and used to generate detailed error budgets and sensitivity curves illustrating the effect of variations in the size of individual error sources on touchdown accuracy. The projected overall performance of each system is shown in the form of time histories of position and velocity error components.

Crawford, B. S.↗
NASA NTRS1975

Measurement of post-separated flow fields on airfoils

Detailed experimental measurements have been made of separated flow fields on a two-dimensional airfoil at low speeds. A rather small pitch yaw pressure probe was chosen. This probe has the capability of remote traversing in the vertical axis and remote yawing of plus or minus 180 deg. The calibration of the probe indicates a useful pitch angle range of about plus or minus 45 deg. The probe and its calibrations provide static and total pressure information as well as three components of velocity. Description and calibration of the probe and typical velocity and pressure plots of the separated flow fields are included.

Seetharam, H. C.↗
NASA NTRS1975

Post-ejection impacts of the space shuttle solid rocket booster nose cap

The dynamics of impacts between the nose cap ejected from the space shuttle solid rocket booster and the drogue parachute pack are analyzed. The analysis is restricted to planar impact, and assumes the law of restitution and the possible occurrence of three types of impact, depending on the friction behavior of the colliding surfaces: forward slip; backward slip; no slip (normal rebound). The positions of both bodies and their velocities at the time of impact are required. Seven successive impacts, representing all three types, detected and simulated for the case of nose cap ejection at 20 fps normal to the direction of airflow, with selected coefficients of friction (0.25) and restitution (0.85).

Banerjee, A. K.↗
NASA NTRS1976

Maneuver sequence design for the post-Jupiter leg of Pioneer Saturn

After passing the planet Jupiter in December 1974, Pioneer 11 is on a flight path on which it will encounter Saturn in late 1979. Following an uncorrected trajectory, the spacecraft would pass 2 million km behind Saturn. A sequence of midcourse maneuvers for modifying the Pioneer trajectory is discussed. The corrected flight path is to bring the spacecraft within 500,000 km of Saturn's satellite Titan. Attention is given to maneuver capabilities and constraints, the maneuver design concept, questions related to the selection of an interim aimpoint, and aspects of maneuver implementation.

Frauenholz, R. B.↗
NASA NTRS1975

Computer analysis of femoral angiograms for evaluation of atherosclerosis in post-infarct males-clinical correlates

Femoral artery atheromatous lesions were studied and their changes as a measure of therapeutic effectiveness were assessed. The incidence of coronary risk factors in 100 patients was determined. Abnormal cholesterol was present in 42 percent, abnormal triglycerides in 66 percent, abnormal intravenous glucose tolerance test in 52 percent, judged from a K value of .9 or less by the technique of Wahlbert. A history of high blood pressure was present in 32 percent. Smoking was one of the most common factors.

Sanmarco, M. E.↗
NASA NTRS1977

Description of a Computer Program Written for Approach and Landing Test Post Flight Data Extraction of Proximity Separation Aerodynamic Coefficients and Aerodynamic Data Base Verification

A computer program written to calculate the proximity aerodynamic force and moment coefficients of the Orbiter/Shuttle Carrier Aircraft (SCA) vehicles based on flight instrumentation is described. The ground reduced aerodynamic coefficients and instrumentation errors (GRACIE) program was developed as a tool to aid in flight test verification of the Orbiter/SCA separation aerodynamic data base. The program calculates the force and moment coefficients of each vehicle in proximity to the other, using the load measurement system data, flight instrumentation data and the vehicle mass properties. The uncertainty in each coefficient is determined, based on the quoted instrumentation accuracies. A subroutine manipulates the Orbiter/747 Carrier Separation Aerodynamic Data Book to calculate a comparable set of predicted coefficients for comparison to the calculated flight test data.

Homan, D. J.↗
NASA NTRS1977

Post Viking planetary protection requirements study

Past planetary quarantine requirements were reviewed in the light of present Viking data to determine the steps necessary to prevent contamination of the Martian surface on future missions. The currently used term planetary protection reflects a broader scope of understanding of the problems involved. Various methods of preventing contamination are discussed in relation to proposed projects, specifically the 1984 Rover Mission.

Wolfson, R. P.↗
NASA NTRS1977

Post LANDSAT D Advanced Concept Evaluation (PLACE)

An outline is given of the mission objectives and requirements, system elements, system concepts, technology requirements and forecasting, and priority analysis for LANDSAT D. User requirements and mission analysis and technological forecasting are emphasized. Mission areas considered include agriculture, range management, forestry, geology, land use, water resources, environmental quality, and disaster assessment.

Source record↗
NASA NTRS1978

A significant post-launch calibration experiment for the SEASAT-A SAR

A technique for periodically monitoring the impulse response function of the SEASAT-A synthetic aperture radar is outlined that yields most of the significant contributors to the overall instrument transfer function. The essential measurement involves exciting the total SAR system at L-band with a strong point source scatterer, receiving via the normal S-band analog data link, and finally sampling and processing only a small subset of data in the immediate vicinity of the strong point source.

Beal, R. C.↗
NASA NTRS1977

SMD 3 post test medical report

One of several reports that were prepared to document the results of the Spacelab Mission Development Test 3 is presented. This report covers clinical support to the crew as well as assistance and counsel to others in crew selection, health stabilization of the crew and the laboratory animals, and habitability and duty schedules.

Hordinsky, J. R.↗