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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 1,225 records · Page 68
All sourcesNASA NTRSDOE OSTI
NASA NTRS1973

Titan/Centaur - NASA's newest launch vehicle.

Titan/Centaur is NASA's last 'new-expendable' launch vehicle prior to the advent of the Space Shuttle. Titan/Centaur is an adaptation of the Air Force Titan III booster with an improved version of the Centaur stage and a new 4.2-meter payload fairing. Titan/Centaur is initially being used for high performance escape missions (Helios Solar Probe - 340 kilograms, Viking Mars Orbiter and Lander - 3,629 kilograms, and Mariner Jupiter/Saturn Fly-Bys at 771 kilograms), but is also particularly suited for larger spacecraft in synchronous orbits (transfer - 7,031 kilograms and equatorial, with three Centaur burns - 3,175 kilograms). The program which began in 1965 with internal NASA feasibility studies will culminate in a 'proof flight' launch in early 1974. With the new payload fairing, which also encloses Centaur, payloads nearly 8.5 meters long and 3.8 meters in diameter can be accommodated.

Stofan, A. J.↗
NASA NTRS1973

Logic-controlled solid-state switchgear for 270 volt dc.

A feasibility study to design and demonstrate solid-state switchgear composed of circuit breakers and a power transfer switch is described. The switchgear operates on a nominal 270 Vdc circuit and controls power to a load up to 15 A. One circuit breaker may be interconnected to a second to form a power transfer switch. Breaker or switch on-off and transfer functions can be remotely controlled. Automatic overload trip-out is provided through an ultimate current trip and an I squared t trip for transient overcurrents lower than the ultimate current trip level. A number of reclosures with variable time delay between trip-out and reclosure are programmed and controlled by integrated analog and COSMOS logic circuits. A commutation circuit that creates minimal transient disturbances to either source or load was developed to interrupt current flow through the main SCR switching element.-

Waddington, D.↗
NASA NTRS1973

Wash water recovery system

The Wash Water Recovery System (WWRS) is intended for use in processing shower bath water onboard a spacecraft. The WWRS utilizes flash evaporation, vapor compression, and pyrolytic reaction to process the wash water to allow recovery of potable water. Wash water flashing and foaming characteristics, are evaluated physical properties, of concentrated wash water are determined, and a long term feasibility study on the system is performed. In addition, a computer analysis of the system and a detail design of a 10 lb/hr vortex-type water vapor compressor were completed. The computer analysis also sized remaining system components on the basis of the new vortex compressor design.

Deckman, G.↗
NASA NTRS1973

Strategy for solar heating and cooling in buildings

The types of solar energy heating and cooling equipment for use with buildings are discussed. The steps from manufacturing to equipment installation are identified. A feasibility study for the use of solar energy was conducted. The study determined the technical, environmental, economic, sociological, political, and strategic aspects of solar heating and cooling.

Source record↗
NASA NTRS1973

Logic-controlled solid state switchgear for 270 volts dc

A feasibility study to design and demonstrate solid state switchgear in the form of circuit breakers and a power transfer switch is described. The switchgear operates on a nominal 270 V dc circuit and controls power to a load of up to 15 amperes. One circuit breaker may be interconnected to a second breaker to form a power transfer switch. On-off and transfer functions of the breakers or the transfer switch are remotely controlled. A number of reclosures with variable time delay between tripout and reclosure are programmed and controlled by integrated analog and COSMOS logic circuits. A unique commutation circuit, that generates only minimal transient disturbance to either source or load, was developed to interrupt current flow through the main SCR switching element. Laboratory tests demonstrated performance of the solid state circuit breakers over specified voltage and temperature ranges.

Sundberg, G. R.↗
NASA NTRS1973

Assessment of lightweight mobile nuclear power systems

A review was made of lightweight mobile nuclear power systems (LMNPS). Data cover technical feasibility studies of LMNPS and airborne vehicles, mission studies, and non-technical conditions that are required to develop and use LMNPS.

Anderson, J. L.↗
NASA NTRS1973

Wind power demonstration and siting problems

Technical and economic feasibility studies on a small windmill to provide overnight charging for an electrically driven car are reported. The auxiliary generator provides power for heating and cooling the vehicle which runs for 25 miles on battery power alone, and for 50 miles with the onboard charger operating. The blades for this windmill have a diameter of 12 feet and are coupled through to a conventional automobile alternator so that they are able to completely recharge car batteries in 8 hours. Optimization of a windmill/storage system requires detailed wind velocity information which permits rational sitting of wind power system stations.

Bergey, K. H.↗
NASA NTRS1974

Feasibility for identification of wheat in Hill County, Montana

Hill County, Montana was the site chosen for feasibility studies concerning wheat crop identification using ERTS 1 multispectral band scanner data, in which the specific objective was to determine whether wheat is spectrally separable from other crops which are typically grown in wheat producing areas. Available computerized techniques were evaluated for their utility in the investigation. It was found that wheat can be separated from other crops with a classification accuracy of roughly 90 percent or better, and that the best single data set occurs after wheat is fully headed and before it turns yellow. The best overall performance was obtained using the three-pass data set using the best 8 channels, or all 12 channels.

Flores, L. M.↗
NASA NTRS1974

Identification and evaluation of educational uses and users for the STS. Educational planning for utilization of space shuttle ED-PLUSS

A planning and feasibility study to identify and document a methodology needed to incorporate educational programs into future missions and operations of the space transportation system was conducted. Six tasks were identified and accomplished during the study. The task statements are as follows: (1) potential user identification, (2) a review of space education programs, (3) development of methodology for user involvement, (4) methods to encourage user awareness, (5) compilation of follow-on ideas, and (6) response to NASA questions. Specific recommendations for improving the educational coverage of space activities are provided.

Engle, H. A.↗
NASA NTRS1973

Atmospheric constituent measurements using commercial 747 airliners

NASA is implementing a global atmospheric monitoring program to measure the temporal and spatial distribution of particulate and gaseous constituents related to aircraft engine emissions in the upper troposphere and lower stratosphere (6 to 12 km). Several 747 aircraft operated by different airlines flying routes selected for maximum world coverage will be instrumented. The initial design of the system (location of equipment, aircraft interfaces, etc.) was conceptually defined in feasibility studies conducted by several airlines and an airframe company. An instrumentation system is now being assembled and tested and is scheduled for operation in airline service in late 1974. An ambient air sampling system was developed to provide undisturbed outside air to the instruments in the pressurized aircraft cabin.

Perkins, P. J.↗
NASA NTRS1973

Design and test of a 100 ampere-hour nickel cadmium battery module

A feasibility study was conducted on the design and construction of a flight-worthy replaceable battery module consisting of four 100 A.H. nickel-cadmium rechargeable cells for large manned space vehicles. The module is planned to weigh less than 43 pounds and be fully maintainable in a zero-g environment by one man without use of special tools. An active environmental control system was designed for the temperature control of the module.

Gaston, S.↗
NASA NTRS1974

Application of remote sensing data to surveys of the Alaskan environment

Coupling of satellite data to resource management problems in Alaska is implemented through feasibility studies of applicability of Landsat data to specific environmental surveys in ecology, agriculture, hydrology, wildlife management, oceanography, geology, etc.; and using the results of these studies to extend the benefits of satellite data applications to the operational needs of mission-oriented agencies of federal, state, and regional governments, as well as private industry. Activities designed to encourage the participation of users in the Landsat program at levels most appropriate to the users' interests are described and include: observation, coordination, and information exchange; training courses and workshops; data exchange; consulting services; data processing services; user participation in University research projects; and university participation in the operational projects of user agencies. Progress in these areas is reported. The effectiveness of this broad-based approach in overcoming the initial apprehensiveness of users is demonstrated.

Belon, A. E.↗
NASA NTRS1975

Mission Analysis Program for Solar Electric Propulsion (MAPSEP). Volume 1: Analytical manual for earth orbital MAPSEP

An introduction to the MAPSEP organization and a detailed analytical description of all models and algorithms are given. These include trajectory and error covariance propagation methods, orbit determination processes, thrust modeling, and trajectory correction (guidance) schemes. Earth orbital MAPSEP contains the capability of analyzing almost any currently projected low thrust mission from low earth orbit to super synchronous altitudes. Furthermore, MAPSEP is sufficiently flexible to incorporate extended dynamic models, alternate mission strategies, and almost any other system requirement imposed by the user. As in the interplanetary version, earth orbital MAPSEP represents a trade-off between precision modeling and computational speed consistent with defining necessary system requirements. It can be used in feasibility studies as well as in flight operational support. Pertinent operational constraints are available both implicitly and explicitly. However, the reader should be warned that because of program complexity, MAPSEP is only as good as the user and will quickly succumb to faulty user inputs.

Source record↗
NASA NTRS1974

Stanford automatic photogrammetry research

A feasibility study on the problem of computer automated aerial/orbital photogrammetry is documented. The techniques investigated were based on correlation matching of small areas in digitized pairs of stereo images taken from high altitude or planetary orbit, with the objective of deriving a 3-dimensional model for the surface of a planet.

Quam, L. H.↗
NASA NTRS1974

Unmanned solar systems exploration - An arena for international cooperation

Mission profiles for a Mars Surface Sample Return (MSSR) mission are considered. A profile using separate launches for a lander/ascent module and an orbiter/return system could use present technology and is appropriate for international cooperation. The achievement of clean interfaces between major building blocks and ease of controlling back contamination are advantages offered by the concept. A spatially distributed surface sample could be obtained by using multiple landers delivering samples to a common orbiter. The Pioneer Venus program, originally planned as a cooperative NASA-ESRO project, resulted in development of a standardized spacecraft bus yielding benefits at minimized cost. The first joint US-European planetary mission now planned is the launch of a Pioneer class orbiter to Jupiter in 1980. Feasibility studies are being conducted.

Herman, D. H.↗
NASA NTRS1974

Propulsion dynamics of lunar hoppers

A feasibility study was recently completed on a hopping transporter concept for locomotion on the moon. Termed a Lunar Pogo because it would operate similarly to a conventional pogo stick, this vehicle would accelerate up an inclined leg, pick up the leg, and then enter ballistic flight over the moon's surface. Upon recontacting the lunar surface, the Lunar Pogo would decelerate down the leg. Propulsion would be provided by expansion of gas against a piston. Operation would be partially conservative because much of the energy expended by the gas during takeoff would be recovered by compressing the gas during landing. Two models of the ballistics and propulsion have been set up to estimate performance. The simplified first-order model illuminates the thermodynamics of ideal operation. The second-order model, which includes realistic effects such as sliding, provides a better approximation to actual performance. In a one-man Lunar Pogo, an astronaut would typically make 15-m (50-ft) leaps at an average speed of 5-8 km (3-5 miles) per hour.

Meetin, R. J.↗
NASA NTRS1975

Mars sample return by orbital rendezvous

The return of Mars surface samples by the orbital rendezvous mode would require smaller, lighter vehicles than the direct return mode and would limit the exposure of the earth return systems to possible contamination by Martian biota. The reference mission considered would use a single Titan IIIE/Centaur launch vehicle, carry a 1 kg sample, and be launched in late 1981. The spacecraft would consist of an orbiter, a Mars lander, a Mars ascent vehicle, an earth return vehicle, and an earth entry capsule. The Mars ascent vehicle is the only all-new vehicle required, the others being derived from Viking and other programs. A key consideration is the feasibility of automatic rendezvous and sample transfer between the ascent vehicle and orbiter in Mars orbit. The maneuvers required and the maneuver algorithm developed in a NASA feasibility study are described in detail. The possibility of international cooperation on a Mars orbital rendezvous mission is discussed.

Moore, J. W.↗
NASA NTRS1974

The use of remote sensing and natural indicators to delineate floodplains - Preliminary findings

Feasibility studies to delineate floodplains using aerial photography have been conducted by the Army Corps of Engineers. The objective of this project is to establish floodplain boundaries using natural indicators such as vegetation types, soil types, moisture differences, and geologic variations. Using aircraft multispectral data, an automated mapping routine should enable the Corps of Engineers to reduce costly field surveys and improve the accuracy of floodplain delineation in pristine areas. The purpose of this paper is to document the methodology utilized in this investigation while using one of a series of available data sets and test sites and to report preliminary findings.

Sollers, S. C.↗