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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 361 records · Page 20

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NASA NTRS1979

Space Shuttle Orbiter - Countdown

The status of Orbiter launch planning is reviewed, with consideration given to major structure elements, subsystem and component development, readiness for launch, and follow-on Orbiters. It is noted that timelines in the completion of each increment of development of the first Orbital Flight Vehicle become increasingly crucial as the scheduled launch date approaches. Concurrent with the testing and finalization of this vehicle's software and hardware construction are the preliminary developmental stages of future Shuttle Orbiters.

Cohen, A.↗

NASA NTRS1979

NOSS flight segment concept study

An 11 ft wide by 26.5 ft long flat structure weighing almost 14,469 pounds evolved during a low level, inhouse conceptual design study for a national oceanic satellite system spacecraft that would stow directly in the space shuttle. Following STS launch to a 300 Km mission orbit inclination, transfer will be effected to a 800 Km Sun synchronous circular orbit. The instrument completement includes 2 altimeters, 1 scatterometer, 1 large antenna multichannel microwave radiometer, and a coastal zone scanner. The spacecraft, its instruments, and interfaces with STS and TDRSS are described. The mission timeline, potential problem areas, system drivers, and recommended study areas are discussed. Drawings and system block diagrams are included.

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NASA NTRS1980

Forest resource information system

Remote sensing technology providing St. Regis with an independent operational system and having LANDSAT data as a significant and viable contributor was documented and transferred. Primary emphasis was placed on documenting developmental LARSYS (LARSYSDV) software modules. Timelines and a short description of the software documentation process is given.

Mroczynski, R. P.↗

NASA NTRS1981

Satellite Power Systems (SPS) concept definition study (Exhibit D). Volume 4: Operations analyses

Using a coplanar, end-mounted antenna as a baseline, various configuration trades were performed to select a preferred solid state concept. The increase in efficiency that could be realized by use of multi bandgap solar cells, either with klystron or solid state antenna was evaluated. Satellite configurations were developed to exploit the sandwich antenna concept wherein solar cells are located on one side of the antenna panel and solid state dc/RF converters on the other side. These concepts entailed various primary and secondary reflector arrangements for directing solar energy to the solar cell side of the antenna with higher concentration ratios than used on the coplanar configurations. Operations analysis included development of a satellite construction scenario, a concept for the SCB, a top-level satellite construction operation, construction operation, construction timelines and crew sizes, mass flows to orbit, and a satellite maintenance scenario. The list of materials required for satellite construction was updated to identify significant differences relevant to the solid state satellite concept. Means of decommissioning satellites at the end of their design life were studied.

Hanley, G. M.↗

NASA NTRS1981

Satellite services system analysis study. Volume 1, part 2: Executive summary

The early mission model was developed through a survey of the potential user market. Service functions were defined and a group of design reference missions were selected which represented needs for each of the service functions. Servicing concepts were developed through mission analysis and STS timeline constraint analysis. The hardware needs for accomplishing the service functions were identified with emphasis being placed on applying equipment in the current NASA inventory and that in advanced stages of planning. A more comprehensive service model was developed based on the NASA and DoD mission models segregated by mission class. The number of service events of each class were estimated based on average revisit and service assumptions. Service Kits were defined as collections of equipment applicable to performing one or more service functions. Preliminary design was carrid out on a selected set of hardware needed for early service missions. The organization and costing of the satellie service systems were addressed.

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NASA NTRS1981

Life sciences passive GN2 freezer thermal performance test

Thermal performance tests that were conducted on the life sciences passive GN2 freezer project are summarized as well as the improvements to the freezers to improve the thermal performance of the containers. Procedures were developed, based upon these tests, to initially charge the freezers with LN2 and verify that the freezer performance is adequate for the mission duration. Improvements were made to the corvac sample tube to limit the amount of breakage due to thermal expansion of the liquid during freezing. A method of verifying the freezer vacuum insulative integrity was defined as well as a procedure for refurbishment of the internal vacuum level. Freezer modifications were made to ease the reevacuation of the containers. The orientation of the freezer in a 1-G environment, after being charged, had to remain in a vertical position. The LN2 boiloff rate increased significantly in a horizontal position. This resulted in a stowage definition in the spacecraft prior to launch. Functional testing, using the SL-1 mission timeline showed that the freezer will maintain samples in the frozen state for the duration of the mission.

Belshaw, G. W.↗

NASA NTRS1980

SPS construction perspective. Summary

Projections concerning the general construction requirements for a solar power satellite (SPS) are summarized. It is recognized that the ability to construct an SPS must be developed through an evolutionary process. This process would begin with shuttle operations and when construction timelines exceed the shuttle capability, small manned bases in low Earth orbit (LEO) would be used. The influence of construction methods on design, assembly bases, and crew considerations are addressed.

Benson, H.↗

NASA NTRS1982

Space Construction Experiment Definition Study (SCEDS), part 2. Volume 2: Study results

The Space Construction Experiment (SCE) was defined for integration into the Space Shuttle. This included development of flight assignment data, revision and update of preliminary mission timelines and test plans, analysis of flight safety issues, and definition of ground operations scenarios. New requirements for the flight experiment and changes for a large space antenna feed mask test article were incorporated. The program plan and cost estimates were updated. Revised SCE structural dynamics characteristics were provided for simulation and analysis of experimental tests to define and verify control limits and interactions effects between the SCE and the Orbiter digital automatic pilot.

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NASA NTRS1982

A possible common origin for the rare gases on Venus, earth, and Mars

The rare gas concentrations in the terrestrial planets and the carbonaceous chondrites could have been derived from a single source an early solar wind. The fractionation processes responsible for the varying concentration patterns in this model are differential ionization and the relative separation of neutrals from ions due to interaction with the solar magnetic field. If species dependent effects are small relative to radius dependent effects, this process can explain in detail both the relative and absolute abundances in the terrestrial planets and carbonaceous chondrites. The electron temperatures predicted by the data are consistent with astrophysical constraints previously derived for the solar nebula, and the timeline of events necessary for this model is consistent with accretion in a gas free environment. If species dependent fractionations are small, or approximately cancel each other, the earth is found to be outgassed by an order of magnitude more efficiently than Venus or Mars.

Hostetler, C. J.↗

NASA NTRS1982

Technical support package: Large, easily deployable structures. NASA Tech Briefs, Fall 1982, volume 7, no. 1

Design and test data for packaging, deploying, and assembling structures for near term space platform systems, were provided by testing light type hardware in the Neutral Buoyancy Simulator. An optimum or near optimum structural configuration for varying degrees of deployment utilizing different levels of EVA and RMS was achieved. The design of joints and connectors and their lock/release mechanisms were refined to improve performance and operational convenience. The incorporation of utilities into structural modules to determine their effects on packaging and deployment was evaluated. By simulation tests, data was obtained for stowage, deployment, and assembly of the final structural system design to determine construction timelines, and evaluate system functioning and techniques.

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NASA NTRS1983

User-programmer dialogue: Guidelines for designing menus and help files for interactive computer systems

This document is a set of guidelines to aid a programmer in making the various decisions necessary for a clear user-programmer dialogue. Its goal is to promote an effective and efficient transfer of information between programmer and user. These guidelines are divided into four sections: (1) Format, (2) Sequence, (3) Audience, and (4) Aim. Format, in terms of this study, means the spatial and structural presentation of information. Sequence deals with the procedural aspects of multiple panel displays. This section looks at the issues of timelines of presentation, modularization of information, and patterns of user behavior. Audience looks at the relationship among programmer, user, and message. It covers the issues of analyzing the audience's knowledge, attitudes, and needs, anticipating the audience's inferences, and identifying textual ambiguities. The programmer's aim or intention shows up in everything from tone to format. Aim considers the programmer's purpose.

Carlson, P. A.↗

NASA NTRS1982

User's appraisal of yield model evaluation criteria

The five major potential USDA users of AgRISTAR crop yield forecast models rated the Yield Model Development (YMD) project Test and Evaluation Criteria by the importance placed on them. These users were agreed that the "TIMELINES" and "RELIABILITY" of the forecast yields would be of major importance in determining if a proposed yield model was worthy of adoption. Although there was considerable difference of opinion as to the relative importance of the other criteria, "COST", "OBJECTIVITY", "ADEQUACY", AND "MEASURES OF ACCURACY" generally were felt to be more important that "SIMPLICITY" and "CONSISTENCY WITH SCIENTIFIC KNOWLEDGE". However, some of the comments which accompanied the ratings did indicate that several of the definitions and descriptions of the criteria were confusing.

Warren, F. B.↗

NASA NTRS1984

41-B tenth Space Shuttle mission

The manned maneuvering unit, two untethered ""spacewalks'', EVA timeline, shuttle pallet satellite, payloads (Palapa-B2, Westar 6), and a rehearsal rendezvous are discussed.

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NASA NTRS1982

Flight data file: STS-4 crew activity plan

The STS-4 Crew Activity Plan contains the on-orbit timeline, which is a flight data file article. Various time scales such as Mission Elapsed Time (MET), Greenwich Mean Time (GMT), and time until deorbit ignition as well as crew activities, day/night, orbit position, ground tracking, communication coverage, attitude, and maneuvers are presented in chart form.

Pippert, E. B., Jr.↗

NASA NTRS1984

Effective organizational solutions for implementation of DBMS software packages

The space telescope management information system development effort is a guideline for discussing effective organizational solutions used in implementing DBMS software. Focus is on the importance of strategic planning. The value of constructing an information system architecture to conform to the organization's managerial needs, the need for a senior decision maker, dealing with shifting user requirements, and the establishment of a reliable working relationship with the DBMS vendor are examined. Requirements for a schedule to demonstrate progress against a defined timeline and the importance of continued monitoring for production software control, production data control, and software enhancements are also discussed.

Jones, D.↗

NASA NTRS1983

Overview of NASA space station activities

The architecture, functions, and human activities on-board a space station are discussed. A manned presence is regarded as essential for innovative actions and successful exploitation of weightless conditions. The station itself could be a cluster of modules for habitation, power, operations, docking, experimentation, and storage. Additionally, the station could provide an interface for free-flying platforms and teleoperated satellite services, as well as a base for establishing space-based manufacturing facilities. NASA has projected timelines that include initial development funding in 1987, full capabilities before the year 2000, and initial costs for minimum capabilities of $7.5-9 billion. Architecture, mission requirements, trade-offs, and concepts are currently being defined as a prelude to systems development. Attention is being given to participation by both the DoD and other governments, and to defining the capabilities of the station, including habitability, closed-loop life-support system, the scope of science application and data transfer, and the power requirements.

Tilton, E. L., III↗

NASA NTRS1984

Three dimensional global modeling of atmospheric CO2

The initial attempts to model the atmospheric CO2 distribution, including couplings to the ocean and biosphere as sources and sinks of atmospheric CO2, encourage the notion that this approach will lead to useful quantitative constraints on CO2 fluxes. Realization of this objective will require: (1) continued improvement in the realism of the global transport modeling; (2) extended timeline of atmospheric CO2 monitoring, which improved precision and improved definition of the uncertainties in the measured CO2 amounts; and (3) given an accurate knowledge of model capabilities and limitations and given a good understanding of CO2 observations and their limitations, there is a need for good ideas concerning what quantitative information on the carbon cycle can be inferred from global modeling.

Hanse, J.↗

NASA NTRS1984

OTV fluid mangement systems

Design, performance, and technology issues associated with reduced gravity propellant management for orbital transfer vehicles (OTV's) are reviewed. The in-space cryogenic management state-of-technology significantly affects the overall confidence level associated with a resupply mission and propulsion performance. Cryogen resupply sequences, timelines, controls, and associated crew involvement are all affected by the technology state. Additionally, OTV propellant tankage configurations, tankage thermodynamic conditions, acceleration environment, propulsion interfaces, and instrumentation are significant factors. Basic propellant transfer phases examined that drive orbital servicing requirements include: (1) tankage preconditioning; (2) tankage chilldown; and (3) propellant fill. Propellant management support of the OTV propulsion phases includes engine restart requirements and orbital coast between engine burns. Technology activities in support of identified technology issues are reviewed.

Hastings, L.↗