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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 469 records · Page 26
All sourcesNASA NTRSDOE OSTI
NASA NTRS1975

Educational planning for utilization of space shuttle (ED-PLUSS). Executive summary: Identification and evaluation of educational uses and users for the STS

The development and application of educational programs to improve public awareness of the space shuttle/space lab capabilities are reported. Special efforts were made to: identify the potential user, identify and analyze space education programs, plan methods for user involvement, develop techniques and programs to encourage new users, and compile follow-on ideas.

Engle, H. A.↗
NASA NTRS1971

Economic analysis of new space transportation systems: Executive summary

An economic analysis of alternative space transportation systems is presented. Results indicate that the expendable systems represent modest investments, but the recurring costs of operation would remain high. The space shuttle and tug system requires a substantial investment, but would substantially reduce the recurring costs of operation. Economic benefits and costs of the different systems are also analyzed. Findings are summarized.

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NASA NTRS1975

Automated Space Processing Payloads Study. Volume 1: Executive Summary

An investigation is described which examined the extent to which the experiment hardware and operational requirements can be met by automatic control and material handling devices; payload and system concepts are defined which make extensive use of automation technology. Topics covered include experiment requirements and hardware data, capabilities and characteristics of industrial automation equipment and controls, payload grouping, automated payload conceptual design, space processing payload preliminary design, automated space processing payloads for early shuttle missions, and cost and scheduling.

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NASA NTRS1975

IUS/TUG Orbital Operations and Mission Support Study: Executive Summary - Volume 1

The space transportation system (STS) is discussed which will include a propulsive stage that is carried into low earth orbit by the space shuttle. Data were accumulated from the analyses of various stage concepts, operating modes, and projected missions (space tug systems studies, growth stage studies, engine studies, and critical area studies). The foundation formulated by these studies aided in establishing a tentative two-phase approach for the extension of the STS operating regime beyond the space shuttle including plane changes, higher orbits, geosynchronous orbits and beyond. The orbital operations study, was conducted to provide the generation and analysis of operational plans, requirement, and concepts for the utilization of these vehicles. Primary emphasis was placed on methods and techniques to provide a sound technical approach to operations at reduced cost for the STS mission period.

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NASA NTRS1975

A study of application of remote sensing to river forecasting. Volume 1: Executive summary

A project is described whose goal was to define, implement and evaluate a pilot demonstration test to show the practicability of applying remotely sensed data to operational river forecasting in gaged or previously ungaged watersheds. A secondary objective was to provide NASA with documentation describing the computer programs that comprise the streamflow forecasting simulation model used. A computer-based simulation model was adapted to a streamflow forecasting application and implemented in an IBM System/360 Model 44 computer, operating in a dedicated mode, with operator interactive control through a Model 2250 keyboard/graphic CRT terminal. The test site whose hydrologic behavior was simulated is a small basin (365 square kilometers) designated Town Creek near Geraldine, Alabama.

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NASA NTRS1975

Space tug/shuttle interface compatibility study. Volume 1: Executive summary

Shuttle interfaces required for space tug accommodation are primarily involved with supporting and servicing the tug during launch countdown, flight, and postlanding; deploying and retrieving the tug on orbit; and maintaining control over the tug when it is in or near the orbiter. Each of these interface areas was investigated to determine the best physical and operational method of accomplishing the required functions, with an overriding goal of establishing simple and flexible orbiter interface requirements suitable for tug, tug payloads, IUS and other cargo. It is concluded the orbiter payload accommodations and the MSFC baseline tug are generally interface compatible. Specific minor changes to tug and orbiter interfaces were identified to provide full compatibility. A system concept for supporting and deploying tug from orbiter is described.

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NASA NTRS1975

Space Tug avionics definition study. Volume 1: Executive summary

A top down approach was used to identify, compile, and develop avionics functional requirements for all flight and ground operational phases. Such requirements as safety mission critical functions and criteria, minimum redundancy levels, software memory sizing, power for tug and payload, data transfer between payload, tug, shuttle, and ground were established. Those functional requirements that related to avionics support of a particular function were compiled together under that support function heading. This unique approach provided both organizational efficiency and traceability back to the applicable operational phase and event. Each functional requirement was then allocated to the appropriate subsystems and its particular characteristics were quantified.

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NASA NTRS1975

Operations analysis (study 2.1). Volume 1: Executive summary

Subjects related to future STS operations concepts were investigated. The majority of effort was directed at assessing the benefits of automated space servicing concepts as related to improvements in payload procurement and shuttle utilization. Another subject was directed at understanding shuttle upper stage software development and recurring costs relative to total program projections. Space serving of automated payloads is addressed by examining the broad spectrum of payload applications with the belief that shared logistic operations will be a major contributor to reduction of future program costs. However, there are certain requirements for support of payload operations, such as availability of the payload, that may place demands upon the shuttle fleet. Because future projections of the NASA Mission Model are only representative of the payload traffic, it is important to recognize that it is the general character of operations that is significant rather than service to any single payload program.

Wolfe, R. R.↗
NASA NTRS1974

System cost performance analysis (study 2.3). Volume 1: Executive summary

A study is described which was initiated to identify and quantify the interrelationships between and within the performance, safety, cost, and schedule parameters for unmanned, automated payload programs. The result of the investigation was a systems cost/performance model which was implemented as a digital computer program and could be used to perform initial program planning, cost/performance tradeoffs, and sensitivity analyses for mission model and advanced payload studies. Program objectives and results are described briefly.

Campbell, B. H.↗
NASA NTRS1975

Orbital assembly and maintenance study. Executive summary

A sound, practical approach for the assembly and maintenance of very large structures in space is presented. The methods and approaches for assembling two large structures are examined. The maintenance objectives include the investigation of methods to maintain five geosynchronous satellites. The two assembly examples are a 200-meter-diameter radio astronomy telescope and a 1,000-meter-diameter microwave power transmission system. The radio astronomy telescope operates at an 8,000-mile altitude and receives RF signals from space. The microwave power transmission system is part of a solar power satellite that will be used to transmit converted solar energy to microwave ground receivers. Illustrations are included.

Gorman, D.↗
NASA NTRS1975

Utility of space transportation system to space communication community: Executive summary

The space transportation system (STS) offers the opportunity for maintaining, and perhaps accelerating, growth of the space communication community. This new launch vehicle service, however, must be obtained at a cost lower than the current expandable launch vehicles cost. A cost competitive STS is defined for geostationary payloads. It is concluded that the STS will be useful to the space communication community, as well as to other geostationary satellite system users, if the proposed recommendations are adapted.

Bronstein, L. M.↗
NASA NTRS1975

Flight-Determined Stability and Control Derivatives for an Executive Jet Transport

A modified maximum likelihood estimation (MMLE) technique which included a provision for including a priori information about unknown parameters was used to determine the aerodynamic derivatives of the Lockheed JetStar airplane. Two hundred sixty-five maneuvers were performed with the JetStar airplane, which was modified to include direct lift controls, to obtain lateral-directional and longitudinal derivatives. Data were obtained at altitudes of 3048 meters, 6096 meters, and 9144 meters (10,000 feet, 20,000 feet, and 30,000 feet) and over an angle of attack range from approximately 3 deg to 13 deg and a Mach number range from 0.25 to 0.75. Side force generators were installed and tested in 87 maneuvers to determine their effectiveness and their effect on the other derivatives. Lateral-directional data for four flight conditions were analyzed without using a priori information to assess the effect of this feature on the results. The MMLE method generally gave consistent (repeatable) estimates of the derivatives, with the exception of the rolling moment due to yaw rate, which showed large variances.

Smith, H. J.↗
NASA NTRS1975

Manned Orbital Systems Concepts Study. Book 1: Executive Summary

Requirements for and definitions of a cost effective orbital facility concept, capable of supporting extended manned operations in earth orbit beyond those visualized for the 7 to 30 day shuttle/spacelab system, were studied. Data are given on requirements derivation, concepts identification, systems analysis and definition, and programmatics.

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NASA NTRS1975

Integrated orbital servicing and payloads study. Volume 1: Executive summary

A study is summarized in which a comparison was made of the following modes of maintaining a satellite system: (1) expendable mode in which failed satellites are replaced, (2) on-orbit servicing where a satellite can be fixed by unmanned module exchange in space, and (3) ground refurbishment in which the satellite is brought back to ground for repairs. It was concluded that on-orbit maintenance is the most cost-effective mode and that it is technically feasible. It can be used to repair failed satellites, to improve reliability of operating satellites, and to update equipment. On-orbit servicing can increase program flexibility and satellite reliability, lifetime, and availability. The significant conclusions and results of two studies are summarized.

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NASA NTRS1975

Integrated orbital servicing study for low-cost payload programs. Volume 1: Executive summary

Various operating methodologies to achieve low-cost space operations were investigated as part of the Space Transportation System (STS) planning. The emphasis was to show that the development investment, initial fleet costs, and supporting facilities for the STS could be effectively offset by exploiting the capabilities of the STS to satisfy mission requirements and reduce the cost of payload programs. The following major conclusions were reached: (1) the development of an on-orbit servicer maintenance system is compatible with many spacecraft programs and is recommended as the most cost-effective system, (2) spacecraft can be designed to be serviceable with acceptable design, weight, volume, and cost effects, (3) use of on-orbit servicing over a 12 year period results in savings ranging between four and nine billion dollars, (4) the pivoting arm on-orbit servicer was selected and a preliminary design was prepared, (5) orbital maintenance has no significant impact on the STS.

Derocher, W. L., Jr.↗
NASA NTRS1975

Manned systems utilization analysis (study 2.1). Volume 1: Executive summary

Man's contribution to the achievement of scientific mission objectives in the space environment is investigated in terms of potential improvement in future applications of scientific instruments relative to the need for interactive manned support operations. Emphasis is placed on experience gained from space programs and the development of empirical techniques to associate the benefit of repair and management actions. Design features are addressed in terms of weight, volume, and reliability associated with designing for space maintenance. The results of the following programs are examined: the OVI series of automated spacecraft; the OSO-7 automated spacecraft; and the Skylab S-056 X-ray telescope experiment in the ATM. It is shown that orbital maintenance is the most realistic means of achieving high system availabilities for scientific instruments.

Wolfe, R. R.↗