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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 127 records · Page 7
All sourcesNASA NTRSDOE OSTI
NASA NTRS1984

Fuel property effects on USN gas turbine combustors

For several years the Department of Defense has been sponsoring fuel accommodation investigations with gas turbine engine manufacturers and supporting organizations to quantify the effect of changes in fuel properties and characteristics on the operation and performance of military engine components and systems. Inasmuch as there are many differences in hardware between the operational engines in the military inventories, due to differences in design philosophy and requirements, efforts were initially expended to acquire fuel effects data from rigs simulating the hot sections of these different engines. Correlations were then sought using the data acquired to produce more general, generic relationships that could be applied to all military gas turbine engines regardless of their origin. Finally, models could be developed from these correlations that could predict the effect of fuel property changes on current and future engines. This presentation describes some of the work performed by Pratt and Whitney Aircraft, under Naval Air Propulsion Center sponsorship, to determine the effect of fuel properties on the hot section and fuel system of the Navy's TF30-P-414 gas turbine engine.

Masters, A. I.↗
NASA NTRS1984

Satellite Emission Range Inferred Earth Survey (SERIES) project

The Global Positioning System (GPS) was developed by the Department of Defense primarily for navigation use by the United States Armed Forces. The system will consist of a constellation of 18 operational Navigation Satellite Timing and Ranging (NAVSTAR) satellites by the late 1980's. During the last four years, the Satellite Emission Range Inferred Earth Surveying (SERIES) team at the Jet Propulsion Laboratory (JPL) has developed a novel receiver which is the heart of the SERIES geodetic system designed to use signals broadcast from the GPS. This receiver does not require knowledge of the exact code sequence being transmitted. In addition, when two SERIES receivers are used differentially to determine a baseline, few cm accuracies can be obtained. The initial engineering test phase has been completed for the SERIES Project. Baseline lengths, ranging from 150 meters to 171 kilometers, have been measured with 0.3 cm to 7 cm accuracies. This technology, which is sponsored by the NASA Geodynamics Program, has been developed at JPL to meet the challenge for high precision, cost-effective geodesy, and to complement the mobile Very Long Baseline Interferometry (VLBI) system for Earth surveying.

Buennagel, L. A.↗
NASA NTRS1984

Status of the National Space Transportation System

The National Space Transportation System is a national resources serving the government, Department of Defense and commercial needs of the USA and others. Four orbital flight tests were completed July 4, 1982, and the first Operational Flight (STS-5) which placed two commercial communications into orbit was conducted November 11, 1982. February 1983 marked the first flight of the newest orbiter, Challenger. Planned firsts in 1983 include: use of higher performance main engines and solid rocket boosters, around-the-clock crew operations, a night landing, extra-vehicular activity, a dedicated DOD mission, and the first flight of a woman crew member. By the end of 1983, five commercial payloads and two tracking and data relay satellites should be deployed and thirty-seven crew members should have made flights aboard the space shuttle.

Abrahamson, J. A.↗
NASA NTRS1985

Air Force satellite position management

The Space Act of 1958 identified the Department of Defense as responsible for conducting military operations in space. Subsequently, the United States Air Force was assigned to act as the DOD's executive agent for space. In addition, the Air Force is responsible for acquisition and launch of DOD space systems. Within the Air Force, space related roles and activities have been delegated to several subordinate organizations and agencies. The roles and responsibilities of agencies are still evolving. The Air Force has designated the Air Force System Command's Space Division as its office of primary responsibility for satellite position management. Spacecraft program offices at Space Division are required by regulation to include position management planning in both prelaunch and orbital phases of spacecraft development and operation.

Davis, R.↗
NASA NTRS1985

Air-sea interaction with SSM/I and altimeter

A number of important developments in satellite remote sensing techniques have occurred recently which offer the possibility of studying over vast areas of the ocean the temporally evolving energy exchange between the ocean and the atmosphere. Commencing in spring of 1985, passive and active microwave sensors that can provide valuable data for scientific utilization will start to become operational on Department of Defense (DOD) missions. The passive microwave radiometer can be used to estimate surface wind speed, total air column humidity, and rain rate. The active radar, or altimeter, senses surface gravity wave height and surface wind speed.

Source record↗
NASA NTRS1985

High-resolution X-ray spectra of solar flares. VII - A long-duration X-ray flare associated with a coronal mass ejection

It has been recognized that very long duration X-ray events (lasting several hours) are frequently associated with coronal mass ejection. Thus, Sheeley et al. (1983) found that the probability of the occurrence of a coronal mass ejection (CME) increases monotonically with the X-ray event duration time. It is pointed out that the association of long-duration, or long-decay, X-ray events (LDEs) with CMEs was first recognized from analysis of solar images obtained by the X-ray telescopes on Skylab and the Naval Research Laboratory (NRL) slitless spectroheliograph. Recently high-resolution Bragg crystal X-ray spectrometers have been flown on three spacecraft, including the Department of Defense P78-1 spacecraft, the NASA Solar Maximum Mission (SMM), and the Japanese Hinotori spacecraft. In the present paper, P78-1 X-ray spectra of an LDE which had its origin behind the solar west limb on November 14, 1980 is presented. The obtained data make it possible to estimate temperatures of the hottest portion of the magnetic loops in which the emission arises.

Kreplin, R. W.↗
NASA NTRS1984

Review of the Tri-Agency Space Nuclear Reactor Power System Technology Program

The Space Nuclear Reactor Power System Technology Program designated SP-100 was created in 1983 by NASA, the U.S. Department of Defense, and the Defense Advanced Research Projects Agency. Attention is presently given to the development history of SP-100 over the course of its first year, in which it has been engaged in program objectives' definition, the analysis of civil and military missions, nuclear power system functional requirements' definition, concept definition studies, the selection of primary concepts for technology feasibility validation, and the acquisition of initial experimental and analytical results.

Ambrus, J. H.↗
NASA NTRS1985

Overview of free-piston Stirling technology at the NASA Lewis Research Center

An overview of the National Aeronautics and Space Administration (NASA) Lewis Research Center (Lewis) free-piston Stirling engine activities is presented. These activities include: (1) a generic free-piston Stirling technology project being conducted to develop technologies synergistic to both space power and terrestrial heat pump applications in a cooperative, cost-shared effort with the Department of Energy (DOE/Oak Ridge National Laboratory (ONRL)), and (2) a free-piston Stirling space-power technology demonstration project as part of the SP-100 program being conducted in support of the Department of Defense (DOD), DOE, and NASA/Lewis. The generic technology effort includes extensive parametric testing of a 1 kw free-piston Stirling engine (RE-1000), development and validation of a free-piston Stirling performance computer code, and fabrication and initial testing of an hydraulic output modification for the RE-1000 engine. The space power technology effort, under SP-100, addresses the status of the 25 kWe Space Power Demonstrator Engine (SPDE) including early test results.

Slaby, J. G.↗
NASA NTRS1985

Software development in Ada

Ada will soon become a part of systems developed for the US Department of Defense. NASA must determine whether it will become part of its environment and particularly whether it will become a part fo the space station development. However, there are several issues about Ada which should be considered before this decision is made. One means of considering these issues is the examination of other developments in Ada. Unfortunately, few full scale developments have been completed or made publicly available for observation. Therefore, it will probably be necessary to study an Ada development in a NASA environment. Another means related to the first is the development of Ada metrics which can be used to characterize and evaluate Ada developments. These metrics need not be confined to full scale developments and could be used to evaluate on going projects as well. An early development in Ada, some observations from that development, metrics which were developed for use with Ada, and future directions for research into the use of Ada in software development in general and in the NASA Goddard environment in particular are described.

Basili, V. R.↗
NASA NTRS1986

Historical data and analysis for the first five years of KSC STS payload processing

General and specific quantitative and qualitative results were identified from a study of actual operational experience while processing 186 science, applications, and commercial payloads for the first 5 years of Space Transportation System (STS) operations at the National Aeronautics and Space Administration's (NASA) John F. Kennedy Space Center (KSC). All non-Department of Defense payloads from STS-2 through STS-33 were part of the study. Historical data and cumulative program experiences from key personnel were used extensively. Emphasis was placed on various program planning and events that affected KSC processing, payload experiences and improvements, payload hardware condition after arrival, services to customers, and the impact of STS operations and delays. From these initial considerations, operational drivers were identified, data for selected processing parameters collected and analyzed, processing criteria and options determined, and STS payload results and conclusions reached. The study showed a significant reduction in time and effort needed by STS customers and KSC to process a wide variety of payload configurations. Also of significance is the fact that even the simplest payloads required more processing resources than were initially assumed. The success to date of payload integration, testing, and mission operations, however, indicates the soundness of the approach taken and the methods used.

Ragusa, J. M.↗
NASA NTRS1986

High precision GPS orbit determination using March 1985 demonstration data

Preliminary orbit determination for satellites in the U.S. Department of Defense's Global Positioning System has been performed using GPS carrier phase data collected in March-April 1985 at 10 sites in the continental United States. The data were analyzed using a new data processing software package called GIPSY (GPS Inferred Positioning SYstem) and with existing covariance analysis software. Data from one day have been processed with average formal position errors of 1.4 to 3.6 meters. The true errors are probably somewhat larger. Covariance results are presented which suggest that the orbits can be obtained with formal errors under 2 meters after certain software issues are resolved.

Bertiger, W.↗
NASA NTRS1986

Future space transportation options - Overview

A comprehensive consideration of space transportation system design possibilities and capabilities has noted that the U.S. (NASA and Department of Defense) launch vehicle users may enter the post-1995 period with a high operating cost space transportation architecture, primarily consisting of a small Space Shuttle fleet and its Complementary Expendable Launch Vehicle for unmanned operations. On the other hand, many technologies critical to the future of space transportation could yield substantial benefits in the post-1995 period. Current funding levels are expected to inhibit the timely development of many such technologies, however, and many current development programs have narrow and short term objectives that will not yield a cohesive data base for further development.

Holloway, P. F.↗
NASA NTRS1986

Structural dynamics research in a full-scale transport aircraft crash test

A remotely piloted air-to-ground crash test of a full-scale transport aircraft was conducted for the first time for two purposes: (1) to demonstrate performance of an antimisting fuel additive in suppressing fire in a crash environment, and (2) to obtain structural dynamics data under crash conditions for comparison with analytical predictions. The test, called the Controlled Impact Demonstration (CID), was sponsored by FAA and NASA with cooperation of industry, the Department of Defense, and the British and French governments. The test aircraft was a Boeing 720 jet transport. The aircraft impacted a dry lakebed at Edwards Air Force Base, CA. The purpose of this paper is to discuss the structural aspects of the CID. The fuselage section tests and the CID itself are described. Structural response data from these tests are presented and discussed. Nonlinear analytical modeling efforts are described, and comparisons between analytical results and experimental results are presented.

Mccomb, H. G., Jr.↗
NASA NTRS1987

NASA/DOD Control/Structures Interaction Technology, 1986

Papers presented at the CSI Technology Conference are given. The conference was jointly sponsored by the NASA Office of Aeronautics and Space Technology and the Department of Defense. The conference is the beginning of a series of annual conferences whose purpose is to report to industry, academia, and government agencies the current status of Control/Structures Interaction technology. The conference program was divided into five sessions: (1) Future spacecraft requirements; Technology issues and impact; (2) DOD special topics; (3) Large space systems technology; (4) Control of flexible structures, and (5) Selected NASA research in control structures interaction.

Wright, Robert L.↗
NASA NTRS1987

Air Force and DOD solar power requirements

It is noted that future power requirements are increasing for some expanded and new missions within the Air Force and Department of Defense. New requirements are needed in terms of lifetime, survivability, power level and performance. The photovoltaic arrays have a demonstrated record of reliable performance, life, affordable cost, and utility. It is argued that there is a need to push for the research and development resources needed to develop the technology base for these future power system needs.

Wise, Joseph F.↗
NASA NTRS1985

A VHSIC general purpose processor

The very high speed integrated circuit (VHSIC) program offers NASA and its contractors assured availability of military specification embedded computer components and integrated computer aided design/computer aided engineering and software development support that result in low system life costs for data management systems on the space station and the Earth Observatory Satellite. Viewgraphs given review progress in both the Department of Defense VHSIC program and the NASA VHSIC related insertion development of a general purpose processor are presented.

Benz, H. F.↗
NASA NTRS1986

Managing Ada development

The Ada programming language was developed under the sponsorship of the Department of Defense to address the soaring costs associated with software development and maintenance. Ada is powerful, and yet to take full advantage of its power, it is sufficiently complex and different from current programming approaches that there is considerable risk associated with committing a program to be done in Ada. There are also few programs of any substantial size that have been implemented using Ada that may be studied to determine those management methods that resulted in a successful Ada project. The items presented are the author's opinions which have been formed as a result of going through an experience software development. The difficulties faced, risks assumed, management methods applied, and lessons learned, and most importantly, the techniques that were successful are all valuable sources of management information for those managers ready to assume major Ada developments projects.

Green, James R.↗
NASA NTRS1986

Run-time implementation issues for real-time embedded Ada

A motivating factor in the development of Ada as the department of defense standard language was the high cost of embedded system software development. It was with embedded system requirements in mind that many of the features of the language were incorporated. Yet it is the designers of embedded systems that seem to comprise the majority of the Ada community dissatisfied with the language. There are a variety of reasons for this dissatisfaction, but many seem to be related in some way to the Ada run-time support system. Some of the areas in which the inconsistencies were found to have the greatest impact on performance from the standpoint of real-time systems are presented. In particular, a large part of the duties of the tasking supervisor are subject to the design decisions of the implementer. These include scheduling, rendezvous, delay processing, and task activation and termination. Some of the more general issues presented include time and space efficiencies, generic expansions, memory management, pragmas, and tracing features. As validated compilers become available for bare computer targets, it is important for a designer to be aware that, at least for many real-time issues, all validated Ada compilers are not created equal.

Maule, Ruth A.↗