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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 181 records · Page 10
All sourcesNASA NTRSDOE OSTI
NASA NTRS1975

Modular bus and payload designs for the Shuttle era

The Space Shuttle, in combination with the Interim Upper Stage, will provide an economical means of placing payloads in geostationary orbit in the 1980s. This paper summarizes a recent study of multidiscipline applications payloads for Shuttle-IUS launch. Various concepts for modular 'bus' spacecraft structures and payload groupings based on equipment commonality are considered. Several bus and payload configurations, ranging from 160 to 1600 kg, are developed. A typical payload is described in some detail. The payload consists of equipment at 400 MHz for search and rescue and data collection, at 1.5 and 15 GHz for aeronautical, maritime, and land mobile communications, at 40 and 90 GHz for millimeter wave communications, and at other bands for meteorological radiometry, electromagnetic environment measurements, and interferometry.

Durrani, S. H.↗
NASA NTRS1976

A new era of space transportation - Future programs

The Space Transportation System - Space Shuttle, Spacelab and Upper Stages - is described from the point of view of systems and operations. Future plans concerning the permanent occupancy of space are examined with emphasis on the Space Construction Base, Advanced Transportation Systems and Space Industrialization plans.

Yardley, J. F.↗
NASA NTRS1976

Shuttle era waste management and biowaste monitoring

The acquisition of crew biomedical data has been an important task on manned space missions. The monitoring of biowastes from the crew to support water and mineral balance studies and endocrine studies has been a valuable part of this activity. This paper will present a review of waste management systems used in past programs. This past experience will be cited as to its influence on the Shuttle design. Finally, the Shuttle baseline waste management system and the proposed Shuttle biomedical measurement and sampling systems will be presented.

Sauer, R. L.↗
NASA NTRS1977

Tracking system performance tests in the MDS era

Tracking system performance tests as developed to support DSN Mark III Data Subsystem implementation project and prepass readiness tests are described. The system test design, the rationale chosen for implementation, and the inevitable compromises imposed by schedule constraints and reserves are discussed.

Buckles, B. J.↗
NASA NTRS1976

Clays as possible catalysts for peptide formation in the prebiotic era

From the point of view of prebiotic synthesis, clays might have performed functions of concentration, catalysis, and protection of molecules. The degrees of polymerization obtained, when amino acid adenylates are added to montmorillonite suspensions in water, are much higher than those obtained by polymerization in the absence of such a clay. In addition, they are of a discrete spectrum, usually multiples of 6 or 7, and reach values of up to 40 mers. In the absence of clay a continuous spectrum of degrees of polymerization is obtained, and usually up to 4-6 mers only. Copolymerization in the absence of clays yields mostly random copolymers, in their presence mostly block copolymers are obtained. Optical density measurements show that after adsorption has taken place on the clay, stacking of its layers occurs. Polymerization starts only after these stacked layers have been formed

Paecht-Horowitz, M.↗
NASA NTRS1977

Opening a new era in space

The overall payload planning aimed at initial projected use of the Space Transportation System (STS) which will establish a new capability for exploring and using space through operations of the Shuttle, Spacelab, and Interim Upper Stage (IUS) in the Eighties is reviewed, and the significance of this planning for science and technology is discussed. The first payloads will fly on the STS during Orbital Flight Tests (OFT) beginning in March 1979. Primary OFT objectives include verifying flight systems and the Shuttle's ability to accomodate various types of payloads in different mission modes. The STS schedule will build up to as many as 60 flights in 1984. The STS payloads will make contributions to the management on a global scale of the interrelationship of production, consumption, population growth, and pollution.

Culbertson, P. E.↗
NASA NTRS1977

The Shuttle era - A challenge to the earth scientist

Satellite observations of large-scale earth features and phenomena, with either instruments or astronauts, are discussed on the basis of earlier experience (mainly Skylab). Off-nadir views and photographs by astronauts have provided valuable supplements to instrument nadir views, providing cross-checks through remote sensing at different angles, different altitudes, and in different seasons. New information on plate tectonics, global cooling/drying trends, global oceanographic data (changing positions of major ocean current patterns, evolution of warm and cold eddies and their relation to sea temperatures and concentrations of marine fauna, location of internal sea waves, interactions between ocean currents and atmosphere, plankton blooms), storm development, snow cover patterns, lake and sea ice growth, sand-dune patterns, desert storms blown out to sea, effects of grazing and swidden agriculture, and other earth features and phenomena are surveyed.

Muehlberger, W. R.↗
NASA NTRS1978

Cometary exploration in the shuttle era

A comprehensive program plan for cometary exploration in the 1980-2000 time frame is proposed. Plans for ground-based observations, a Spacelab cometary observatory, and the Space Telescope are included in the observational program. The cometary mission sequence begins with a dual-spacecraft flyby of Halley's comet. The nominal mission strategy calls for a simultaneous launch of two spacecraft towards an intercept with Halley in March 1986. After the Halley encounter, the spacecraft are retargeted: one to intercept comet Borrelly in January 1988 and the other to intercept comet Tempel-2 in September 1988. The additional cometary intercepts are accomplished by utilizing a novel Earth-swingby technique. The next mission in the cometary program plan, a rendezvous with Encke's comet, is scheduled for launch in early 1990. It is planned to rendezvous with Encke in September 1992 at a heliocentric distance of 4 AU. Following this near-aphelion rendezvous, the spacecraft will remain with with Encke through the next two perihelion passages in February 1994 and May 1997. The rendezvous mission will be terminated about seven months after the second perihelion passage.

Farquhar, R. W.↗
NASA NTRS1978

Evidence for a primordial magnetic field during the meteorite parent body era

Data on 247 meteorites were examined, and a log-log plot of the magnetic moment/gm versus the susceptibility/gm reveals a straight-line relation with a slope of unity for a range of meteorite types extending from achondrites at the low Fe-Ni end to stony-irons. The relation holds for a span of parameter values ranging between four and five orders. The results support the hypothesis of a common background magnetic field at the time of meteorite formation. An equation relating the primordial field strength to the average carrier demagnetization factor, which can vary from 0 to 4 pi, is presented. The extreme lower limit for the field strength is 0.02 oersted, while for the mean field of 0.27 oersted determined from a study of individual meteorites (Stacy and Banerjee, 1974), the average value for the carrier demagnetization factor is 0.74, corresponding to elongated grains.

Sonett, C. P.↗
NASA NTRS1978

Peptide formation in the prebiotic era - Thermal condensation of glycine in fluctuating clay environments

As geologically relevant models of prebiotic environments, systems consisting of clay, water, and amino acids were subjected to cyclic variations in temperature and water content. Fluctuations of both variables produced longer oligopeptides in higher yields than were produced by temperature fluctuations alone. The results suggest that fluctuating environments provided a favorable geological setting in which the rate and extent of chemical evolution would have been determined by the number and frequency of cycles.

Lahav, N.↗
NASA NTRS1978

Planning a new era in air transport efficiency

The current status of the NASA Aircraft Energy Efficiency (ACEE) program is briefly reviewed with reference to CTOL aircraft. Attention is given to four basic technologies: turboprop, advanced aerodynamics and active controls, laminar flow control, and composites.

Kramer, J. J.↗
NASA NTRS1978

Life sciences in the Shuttle era

The effect of the Shuttle program on life science research and the life science research community is examined. Responses to a NASA invitation to participate in planning the life sciences program in space are considered. The development of life science space equipment is surveyed.

Deutsch, S.↗
NASA NTRS1978

STDN in the TDRSS and Shuttle Era

NASA presently maintains a worldwide system of ground tracking stations to provide communication support (tracking, telemetry and command) to all authorized user spacecraft missions. The set of ground stations supporting earth orbiting missions, and their supporting communication links (called NASCOM) to various NASA centers, is designated as the Spaceflight Tracking and Data Network (STDN). Major users of the STDN in the 1980's include LANDSAT-D, SEASAT-B and the Shuttle, all of which are capable of generating data at rates that cannot be handled by the present STDN ground stations. The expanded capabilities of the STDN in the 1980's to provide support to these missions and other users is addressed. The newest asset of the STDN, the Tracking and Data Relay Satellite System (TDRSS) is described, as are the remaining STDN ground stations (called the GSTDN). The Shuttle communications support is not only for the Shuttle itself, but also for the Spacelab, attached payloads (within the Shuttle bay), and detached payloads being either deployed or retrieved by Shuttle. The specific communications support being provided by STDN (both by TDRSS and by the GSTDN) to the Shuttle is also described.

Schwartz, J. J.↗
NASA NTRS1979

Free-flying Shuttle payloads - An extrapolation of sounding rocketry into the Shuttle era

A concept is described for flying scientific and other instruments on the Shuttle, using a free-flying payload. Low costs are maintained by minimizing interfaces with the Space Transportation System and by assembling the payload using modified sounding rocket hardware. This approach allows all Shuttle missions to be considered for scientific missions and gives the Spacelab program the freedom to concentrate on those missions which can take special advantage of supervision by the Orbiter crew.

Olney, D. J.↗
NASA NTRS1979

Managing tort liability risks in the era of the Space Shuttle

A new section, named section 308 on 'Insurance and Indemnification', that was added to the National Aeronautics and Space Act of 1958, is discussed. The reasons behind the NASA proposed section are examined, and its various provisions mentioned, as well as outlining the steps needed to implement these provisions. Attention is given to the tort liability risks and to the various costs that NASA would need to cover in case of liability for death, bodily harm, or damage to property resulting from activities carried on in connection with the landing, operations or recovery of the Space Shuttle. The entire section and its six subsections are presented in two appendices.

Mossinghoff, G. J.↗
NASA NTRS1980

Preparing aircraft propulsion for a new era in energy and the environment

Improving fuel efficiency, new sources of jet fuel, and noise and emission control are subjects of NASA's aeronautics program. Projects aimed at attaining a 5% fuel savings for existing engines and a 13-22% savings for the next generation of turbofan engines using advanced components, and establishing a basis for turboprop-powered commercial air transports with 30-40% savings over conventional turbofan aircraft at comparable speeds and altitudes, are discussed. Fuel sources are considered in terms of reduced hydrogen and higher aromatic contents and resultant higher liner temperatures, and attention is given to lean burning, improved fuel atomization, higher freezing-point fuel, and deriving jet fuel from shale oil or coal. Noise sources including the fan, turbine, combustion process, and flow over internal struts, and attenuation using acoustic treatment, are discussed, while near-term reduction of polluting gaseous emissions at both low and high power, and far-term defining of the minimum gaseous-pollutant levels possible from turbine engines are also under study.

Stewart, W. L.↗