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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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Two-axis winching and traversing device is used for installing liquid-propellant rocket-engine fuel and liquid oxygen suction ducts between the valves and the rocket engine on a test stand. The device raises and maneuvers the duct into the required position where it can be safely installed by mechanics.
Mathematical models for probability of successful traverse of asteroid belt or zero penetration of spacecraft shield
Radio ray scattering resulting from traversing anisotropically turbulent solar corona, noting refraction effect on signal pulse arrival time
Effective heat transfer coefficient lambda for microscopic Fe particles traversing rarefied air, oxygen and Ar target gases
MHD Rankine-Hugoniot equations for ion density, thermal pressure and convective velocity magnitude and orientation during Pioneer 6 traversal of earth bow shock
Interstellar propagation effect on spectra and charge ratios due to ionization energy loss and nuclear spallation during traversal of matter
Energy loss of high energy cosmic rays traversing isotropic radiation field of arbitrary energy spectrum in pair producing collisions with ambient photons
Development of gravimeter for lunar traverse gravity experiment and specifications for instrument, operation, and experiment error budget
Total cross section measurements for formation of metastable hydrogen atoms by charge transfer of proton traversed targets of helium, argon, nitrogen, and oxygen
Photographs and descriptions of Apollo 15 at Hadley base and lunar rover traverses
Differential energy losses of alpha particles traversing materials in superconducting and normal states
The OGO-6 electric field measurements make it clear that the general pattern of high latitude electric fields in magnetic time-invariant latitude coordinates is not highly variable and that when unusual variations, or field distributions, occur they are relatively isolated in time and spatial extent. Thus, electric field changes on a global scale cannot, in general, be evoked as a direct cause of substorms. Polar traverses along the 18(h) to 6(h) magnetic time meridian show that the sum of potential drops across the evening auroral belt and morning auroral belt approximately equals the potential drop across the polar cap. The integrated polar cap potential drop ranges from 20 to 100 keV and values in the center of this range are most common under conditions of moderate magnetic disturbance. Roughly near 18(h) magnetic local time, a latitudinally narrow strip at the transition between auroral belt and polar cap fields exhibits unusually large field fluctuations immediately following the sudden onset of a negative bay at later magnetic local times. It appears likely that this spatially isolated correlation is related to an effect rather than a cause of substorm enhancement.
The unsteady aerodynamics of the proposed delta planform, high cross range, shuttle orbiters, are investigated. It is found that these vehicles are subject to five unsteady-flow phenomena that could compromise the flight dynamics. The phenomena are as follows: (1) leeside shock-induced separation, (2) sudden leading-edge stall, (3) vortex burst, (4)bow shock-flap shock interaction, and (5) forebody vorticity. Trajectory shaping is seen as the most powerful means of avoiding deterimental effects of the stall phenomena; however, stall must be fixed or controlled when traversing the stall region. Other phenomana may be controlled by carefully programmed control deflections and some configuration modifications. Ways to alter the occurrence of the various flow conditions are explored.
The unsteady aerodynamics of the delta planform, high cross range, shuttle orbiter were investigated. It has been found that these vehicles are subject to five unsteady flow phenomena that could compromise the flight dynamics. They are: (1) leeside shock induced separation, (2) sudden leading edge stall, (3) vortex burst, (4) bow shock-flap shock interaction, (5) forebody vorticity. Trajectory shaping is seen as the most powerful means of avoiding the detrimental effects of the stall phenomena. However, stall must be fixed or controlled when traversing the stall region. The other phenomena may be controlled by carefully programmed control deflections and some configuration modification. Ways to alter the occurrence of the various flow conditions are explored.
The Apollo 15 manned lunar-landing mission is discussed. As compared with previous Apollo manned lunar-landing missions, the mission 15 is characterized by increased hardware capability, a larger scientific payload, and a battery-powered lunar roving vehicle (Rover). Benefits resulting from these additions to Apollo 15 were a mission duration of 12-1/3 days, a lunar stay time of nearly 67 hr, a lunar-surface traverse distance of 27.9 km traveled at an average speed of 9.6 km/hr, and a scientific instrument module (SIM) containing equipment for orbital experiments and photographic tasks not performed on previous missions. The primary scientific objectives of the mission were to perform selenological inspection, survey, and sampling of materials and surface features in a preselected area of the Hadley-Apennine region; to emplace and activate surface experiments; and to conduct inflight experiments and photographic tasks from lunar orbit.
Crew observations of the Apollo 15 flight are presented. The observations are concerned with the following phases of the flight: (1) translunar and transearth coasts, (2) lunar landing and ascent, (3) standup extravehicular activity, (4) surface experiment deployment, (5) lunar traverse geology, and (6) orbital observations.
The Apollo 15 lunar module (LM) landed on the mare surface of Palus Putredinis on the eastern edge of the Imbrium Basin. The site is between the Apennine Mountain front and Hadley Rille. The objectives of the mission, in order of decreasing priority, were description and sampling of three major geologic features-the Apennine Front, Hadley Rille, and the mare. The greater number of periods of extravehicular activity (EVA) and the mobility provided by the lunar roving vehicle (ROVER) allowed much more geologic information to be obtained from a much larger area than those explored by previous Apollo crews. A total of 5 hours was spent at traverse station stops, and the astronauts transmitted excellent descriptions of the lunar surface while in transit between stations.
An array of sensitive electrostatic analyzers was launched on the satellite INJUN 5 into a nearly polar, low altitude orbit. A series of three traversals of the northern auroral zone in the local evening sector on 3 December 1968 has provided high energy- and time-resolution observations of low-energy proton and electron intensities within the energy range 50 smaller than E smaller than 15,000 eV before, during and after a polar magnetic substorm. The region of high intensities of plasma-sheet electrons expanded dramatically during the substorm, extending 3.5 deg farther poleward and approximately 4.5 deg farther equatorward relative to that of the preceding pass.