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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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NASA NTRS1976

Gravity and embryonic development

The relationship between the developing embryo (both plant and animal) and a gravitational field has long been contemplated. The difficulty in designing critical experiments on the surface of the earth because of its background of 1 g, has been an obstacle to a resolution of the problem. Biological responses to gravity (particularly in plants) are obvious in many cases; however, the influence of gravity as an environmental input to the developing embryo is not as obvious and has proven to be extremely difficult to define. In spite of this, over the years numerous attempts have been made using a variety of embryonic materials to come to grips with the role of gravity in development. Three research tools are available: the centrifuge, the clinostat, and the orbiting spacecraft. Experimental results are now available from all three sources. Some tenuous conclusions are drawn, and an attempt at a unifying theory of gravitational influence on embryonic development is made.

Young, R. S.↗

NASA NTRS1977

Development of shuttle payloads

The development of payloads for the Shuttle is described in terms of two activities - one is oriented towards development of payload hardware, while the other is oriented towards the development of payload/Space Transportation System (STS) planning, scheduling, and integration techniques. This second activity is called STS Utilization Planning (SUP). In addition to describing the major aspects of SUP, a discussion of development activities on three payloads that typify direct Shuttle placement missions is included. These payloads are the First Spacelab Mission, the Atmospheric, Magnetospheric, and Plasmas in Space (AMPS) payload, and the Large Space Telescope (LST).

Murphy, J. T.↗

NASA NTRS1978

Development of automatic and manual flight director landing systems for the XV-15 tilt rotor aircraft in helicopter mode

The objective of this effort is to determine IFR approach path and touchdown dispersions for manual and automatic XV-15 tilt rotor landings, and to develop missed approach criteria. Only helicopter mode XV-15 operation is considered. The analysis and design sections develop the automatic and flight director guidance equations for decelerating curved and straight-in approaches into a typical VTOL landing site equipped with an MLS navigation aid. These system designs satisfy all known pilot-centered, guidance and control requirements for this flying task. Performance data, obtained from nonstationary covariance propagation dispersion analysis for the system, are used to develop the approach monitoring criteria. The autoland and flight director guidance equations are programmed for the VSTOLAND 1819B digital computer. The system design dispersion data developed through analysis and the 1819B digital computer program are verified and refined using the fixed-base, man-in-the-loop XV-15 VSTOLAND simulation.

Hofmann, L. G.↗

NASA NTRS1977

Energy resources of the developing countries and some priority markets for the use of solar energy

Energy consumption for the developed and non-developed world is expressed as a function of GNP. An almost straight-line graph results when energy consumption statistics are treated in this manner. The richest countries consume the most energy, and the poorest countries the least. It therefore follows that greater energy production in the developing countries (leading to greater energy consumption) will contribute to their economic growth. Energy resources in the developing countries are compared, including: solid fossil fuels, crude oil, natural gas, oil shale, and uranium. Mention is also made of the potential of renewable energy resources, such as solar, wind, and hydroelectric power, in the underdeveloped world; and it is these resources which offer the greatest possibilities for economic improvement if the money is forthcoming, i.e., from the world bank, to fund the necessary technology.

Siddiqi, T. A.↗

NASA NTRS1978

Flight simulation - A vital and expanding technology in aircraft development

Flight simulation, both ground and in-flight, is experiencing major technological improvement and growth. The increased capabilities are providing new opportunities for support of the aircraft development process. The development of faster digital computers, improved visual displays, better motion systems and increased interest in simulation fidelity has improved the ground simulator to the point where it accomplishes a major portion of the aircraft development before work on the flight article begins. The efficiency of the ground simulator as a forecaster for the flight testing phase is becoming well established. In-flight simulation is properly being used to bridge the gap between the ground simulator and the flight test article. Simulation provides the vital link between analysis, aerodynamic tests, and subsystem tests and the flight test article. This paper describes the latest advances in flight simulation and its increasing role in the aircraft development process.

Reynolds, P. A.↗

NASA NTRS1978

Manned remote work station development article

The two prime objectives of the Manned Remote Work Station (MRWS) Development Article Study are to first, evaluate the MRWS flight article roles and associated design concepts for fundamental requirements and embody key technology developments into a simulation program; and to provide detail manufacturing drawings and schedules for a simulator development test article. An approach is outlined which establishes flight article requirements based on past studies of Solar Power Satellite, orbital construction support equipments, construction bases and near term shuttle operations. Simulation objectives are established for those technology issues that can best be addressed on a simulator. Concepts for full-scale and sub-scale simulators are then studied to establish an overall approach to studying MRWS requirements. Emphasis then shifts to design and specification of a full-scale development test article.

Source record↗

NASA NTRS1979

Development and fabrication of high strength alloy fibers for use in metal-metal matrix composites

Metal fiber reinforced superalloys are being considered for construction of critical components in turbine engines that operate at high temperature. The problems involved in fabricating refractory metal alloys into wire form in such a manner as to maximize their strength properties without developing excessive structural defects are described. The fundamental principles underlying the development of such alloy fibers are also briefly discussed. The progress made to date in developing tungsten, tantalum and columbium base alloys for fiber reinforcement is reported and future prospects for alloy fiber development considered.

King, G. W.↗

NASA NTRS1979

Development of drive mechanisms for communicaton satellites

A distinguished pedigree is an important asset in the development of Aerospace mechanisms. Four drives recently developed for communication satellites are outgrowths of a previously-proven drive configuration. Pedigree by itself, however is not enough to generate success. Inevitably, design changes which are thought to be minor, are generally introduced to fine tune the pedigreed hardware to meet particular requirements of a specific new application. Such design changes are often viewed too casually and are not thoroughly tested in the early development stages of the program. Two areas of design change are described on the solar array drive applied to the Japanese Broadcast Satellite which led to subsequent problems during the development phase of the program. The methods applied to establish the cause and the solution of these problems are described as well as the testing approach adapted to prevent similar occurrences on the current Communication Satellite Program, The Defense System Communications Satellite III.

Schneider, A. C.↗

NASA NTRS1979

LaRC-160 fabrication development

The scope and status of the fabrication development program on the third candidate graphite/polyimide material, utilizing the LARC-160 polyimide system is reported. The results of initial chemical characterization studies on resin monomer constituents and intermediate esters are discussed, in particular, the problem of identifying the nadic ester endcapper material and establishing specifications to ensure material reproducibility. Progress on the process development task, including prestaging, cure, and postcure studies on flat laminates is reported. In addition, the design and processing of hat and "I" section stiffeners is reviewed. Initial efforts on the development of standards for nondestructive C-scan inspection for the various types of structures are discussed. The approach to qualifying the developed processes is outlined along with other ancillary studies in progress.

Leahy, J. D.↗

NASA NTRS1979

Deployable antenna technology development for the Large Space Systems Technology program

The critical technologies associated with the development of deployable reflector antenna technology for the LSST program will be derived from NASA mission models and the subsequent requirements will be related to the classes of missions involved. The approach formulated for the development of reflector technology is based on the development of specific reflector concepts that have been identified as leading candidates for future applications. The development approach will be augmented by supporting technology disciplines such as controls, materials, electromagnetic analysis, as well as the capability of analytically predicting the overall performance of the large space system.

Freeland, R. E.↗

NASA NTRS1979

The selection of materials technologies for full-scale development

Candidate material technologies offering the largest application payoff for the least development costs and the least risk should be selected for full-scale development funding. A cost/benefit methodology is developed to rate candidate material and process opportunities for future aircraft engine applications. A development cost estimate and risk analysis is compared with the economic benefit to establish a ranking of the candidate advanced technologies. Also included are examples of this methodology as applied to high-strength HIP turbine disks, advanced oxide dispersion strengthened burner liners, and ceramic first-stage high-pressure turbine vanes.

Aronstamm, G. A.↗

NASA NTRS1979

Accuracy and performance of LACIE crop development models

Of the three principal phenological crop calendar models evaluated for LACIE, Robertson's triquadratic model which predicts the rate of progression of wheat through its biological development, was selected. Daily maximum and minimum temperatures and day length are the input variables, and the principal output is a daily increment of development through six physiological growth stages. Because wheat corresponds differently to the environment during each growth stage, five different equations are required. The estimated and observed crop development data were compared in order to establish a measure of confidence in the model and to identify consistent discrepancies that would adversely affect LACIE operation. Although the model provided reliable estimates for various wheat growing regions of the world, it was found that there are still areas in need of further model improvement or development.

Woolley, S. K.↗

NASA NTRS1980

FY-79 - LSST antenna technology development

The development of technology needed to design, fabricate, transport, and deploy large antenna systems is reported. Accomplishments include: (1) development of scenarios for near term missions in communications, microwave radiometry, and radio astronomy; (2) conceptual designs for critical components of a hoop/column reflector; (3) development of a surface accuracy measurement system; and (4) development of electromagnetic analysis methods for large aperture antennas.

Campbell, T. G.↗

NASA NTRS1980

Supporting research and technology for automotive Stirling engine development

The technology advancement topics described are a part of the supporting research and technology (SRT) program conducted to support the major Stirling engine development program. This support focuses on developing alternatives or backups to the engine development in critical areas. These areas are materials, seals control, combustors and system analysis. Specific objectives and planned milestone schedules for future activities as now envisioned are described. These planned SRT activities are related to the timeline of the engine development program that they must support.

Tomazic, W. A.↗

NASA NTRS1980

Design of slotted transonic wind tunnels for supersonic flow development

A simple analytical method to predict the supersonic flow development in a two-dimensional slotted transonic wind tunnel has been developed and validated. While doing that, an insight has been gained into the flow mechanism which causes overexpansion with some slot shapes. As a consequence of the success of the analysis method, a design method has been developed on similar lines, to obtain slot shapes for prescribed smooth supersonic flow development at a design Mach number. The performance of these slot shapes at off-design conditions have been studied to enable choice of slot shapes to be made, based on acceptable performance over the whole supersonic range of interest.

Ramaswamy, M. A.↗

NASA NTRS1980

Development and implementation of Shuttle/IUS proximity operations flight design software

The High Fidelity Relative Motion Program (HFRMP), a trajectory/attitude numerical integration program, was developed and implemented on the MPAD HP-9825A desk top computer systems. A solar and a lunar ephemeris is included in the HFRMP along with models of the oblate Earth, a rotating atmosphere, the orbiter's OMS/RCS/DAP system, orbiter vents, rotor dynamics, and upper stage propulsion systems. Although designed primarily for the analysis of proximity operations, it is useful in other areas such as attitude/stability analysis, propulsive consumables estimation, and trajector perturbation studies. An unique identification was assigned to each of the various configurations of the HFRMP that were developed to test new techniques and algorithms are briefly described. These include the HFRMP Versions 03H, 03M, 03T, 03U, and 05D. Development of orbiter/upper stage separation techniques including flight design support for the TDRS-A and Galileo deployment flights and design of standard maneuver sequences is discussed. Also, the development and implementation of the Euler angle conversion program is briefly addressed.

Wilson, S. W.↗

NASA NTRS1980

Market definition study of photovoltaic power for remote villages in developing countries

The potential market of photovoltaic systems in remote village applications in developing countries is assessed. It is indicated that photovoltaic technology is cost-competitive with diesel generators in many remote village applications. The major barriers to development of this market are the limited financial resources on the part of developing countries, and lack of awareness of photovoltaics as a viable option in rural electrification. A comprehensive information, education and demonstration program should be established as soon as possible to convince the potential customer countries and the various financial institutions of the viability of photovoltaics as an electricity option for developing countries.

Ragsdale, C.↗

NASA NTRS1980

Methodology for urban rail and construction technology research and development planning

A series of transit system visits, organized by the American Public Transit Association (APTA), was conducted in which the system operators identified the most pressing development needs. These varied by property and were reformulated into a series of potential projects. To assist in the evaluation, a data base useful for estimating the present capital and operating costs of various transit system elements was generated from published data. An evaluation model was developed which considered the rate of deployment of the research and development project, potential benefits, development time and cost. An outline of an evaluation methodology that considered benefits other than capital and operating cost savings was also presented. During the course of the study, five candidate projects were selected for detailed investigation; (1) air comfort systems; (2) solid state auxiliary power conditioners; (3) door systems; (4) escalators; and (5) fare collection systems. Application of the evaluation model to these five examples showed the usefulness of modeling deployment rates and indicated a need to increase the scope of the model to quantitatively consider reliability impacts.

Rubenstein, L. D.↗