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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 55 records · Page 3
All sourcesNASA NTRSDOE OSTI
NASA NTRS1975

Quiet clean short-haul experimental engine /QCSEE/ design rationale

The principal design features of the NASA QCSEE Under-The-Wing and Over-The-Wing powered lift propulsion systems are given. In the UTW engine, these include noise reduction features, a variable pitch low pressure ratio fan, a fan drive reduction gear, an advanced core and low pressure turbine with a low pollution combustor, a digital control, and advanced composite construction for the inlet, fan frame, fan exhaust duct, and variable area fan exhaust nozzle. The OTW engine is similar but has higher fan pressure and a fixed pitch fan. Both engines are scheduled to be fabricated and tested starting in 1976.

Adamson, A. P.↗
NASA NTRS1976

The rationale and design features for the 40 by 80/80 by 120 foot wind tunnel

A substantial increase in the test capability of full scale wind tunnels is considered. In order to determine the most cost effective means for providing this desired increase in test capability, a series of design studies were conducted of various new facilities as well as of major modifications to the existing 40- by 80-foot wind tunnel. The most effective trade between test capability and facility cost was provided by repowering the existing 40 by 80 foot wind tunnel to increase the maximum speed from 200 knots to 300 knots and by the addition of a new 80- by 120-foot test section having a 110 knot maximum speed. The design of the facility is described with special emphasis on the unique features, such as the drive system which absorbs nearly four times the power without an increase in noise, and the large flow diversion devices required to interface the two test sections to a single drive.

Mort, K. W.↗
NASA NTRS1976

Rationale and description of a coordinated cockpit display for aircraft flight management

The design for aircraft cockpit display systems is discussed in detail. The system consists of a set of three beam penetration color cathode ray tubes (CRT). One of three orthogonal projects of the aircraft's state appears on each CRT which displays different views of the same information. The color feature is included to obtain visual separation of information elements. The colors of red, green and yellow are used to differentiate control, performance and navigation information. Displays are coordinated in information and color.

Baty, D. L.↗
NASA NTRS1976

Rationale for structural inspections

The methods developed to predict the reliability of aircraft structures depend upon inspection effectiveness which, in turn, depends upon structural complexity, quality, and the percentage of the structure inspected. Reliability can be enhanced by choosing materials properly, designing damage-tolerant structures, and increasing inspection frequency. And, for fleet operations, costs can be minimized through proper inspection schedules, and enhanced reliability can be compatible with minimum cost. The methods are derived from a combination of probability theory and engineering equations. A discussion of these methods is presented.

Davidson, J. R.↗
NASA NTRS1977

Scientific rationale and strategies for a first comet mission: Report of the Comet Halley science working group

The science objectives of a first comet mission are reviewed and related to what is known or can be expected to be learned in the near future from ground-based and near earth observations. A set of instruments and their science objectives are defined for a mission to Comet Halley during its 1985/86 apparition. The benefits from a fast flyby, a slow flyby, or a rendezvous mission and the relative impact of each on the instrument payload were assessed. The relative scientific value of encounters with the comet at distances from the sun ranging from 1 AU to 2.5 AU, including possible tradeoffs between flyby velocity and distance was considered. Pre- and post-perihelion encounters were likewise evaluated.

Source record↗
NASA NTRS1977

Scientific rationale and strategies for a first comet mission. Report of the Comet Halley science working group. An executive summary

The justification, scientific objectives, instrumentation, and strategy for a first comet mission are discussed. Topics include: mission target; rendezous, propulsion system requirements, measurement objectives, instrument capabilities for rendezvous and the tail probe payload, and backup missions if rendezvous with Halley's comet is not possible to achieve. Support research to be done by NASA is recommended.

Source record↗
NASA NTRS1977

The next 25 years: Industrialization of space - Rationale for planning

A methodology for planning the industralization of space is discussed. The suggested approach combines the extrapolative ('push') approach, in which alternative futures are projected on the basis of past and current trends and tendencies, with the normative ('pull') view, in which an ideal state in the far future is postulated and policies and decisions are directed toward its attainment. Time-reversed vectors of the future are tied to extrapolated, trend-oriented vectors of the quasi-present to identify common plateaus or stepping stones in technological development. Important steps in the industrialization of space to attain the short-range goals of production of space-derived energy, goods and services and the long-range goal of space colonization are discussed.

Von Puttkamer, J.↗
NASA NTRS1976

The next 25 years: Industrialization of space: Rationale for planning

The goals of NASA's space industralization program include contributing to increased productivity on earth without taxing the environment, generating new values through extraterrestrial productivity, and providing new growth options for the future which include the permanent settlement of space and long-range colonization and exploration projects. In planning the long-range space program based on essentially utilitarian aspects, without losing sight of the more humanistically significant long term, and to forecast associated technology requirements, a realistic approach is obtained by combining extrapolative and normative planning modes so that common stepping stones can be identified. In the extrapolative view, alternative futures are projected on the basis of past and current trends and tendencies. In the normative view, some ideal state in the far future is envisioned or postulated, and policies and decisions are directed toward its attainment.

Vonputtkamer, J.↗
NASA NTRS1977

Rationale for selection of a flight control system for lift cruise fan V/STOL aircraft

Various features of the lift cruise fan V/STOL concept are briefly reviewed. The ability to operate from small ships in adverse weather, low visibility, and rough sea conditions is emphasized as is the need for a highly capable, flexible, and reliabile flight control system. A three channel control by wire, digital flight control system is suggested. The requirement for automatic flight control, the advantage of control by wire implementation, the preference for a digital computer, and the need for three channel redundancy are among the factors discussed.

Konsewicz, R. K.↗
NASA NTRS1978

A rationale for technology transfer

Specific contributions of the NASA Technology Utilization Program are outlined, including: improved firefighting equipment, electrical implants for medical purposes, and improved methods of weather forecasting. Cooperation between NASA and other organizations in both the public and private sectors is stressed.

Gray, E. Z.↗
NASA NTRS1981

Surface penetrators for planetary exploration: Science rationale and development program

Work on penetrators for planetary exploration is summarized. In particular, potential missions, including those to Mars, Mercury, the Galilean satellites, comets, and asteroids are described. A baseline penetrator design for the Mars mission is included, as well as potential instruments and their status in development. Penetration tests in soft soil and basalt to study material eroded from the penetrator; changes in the structure, composition, and physical properties of the impacted soil; seismic coupling; and penetrator deflection caused by impacting rocks, are described. Results of subsystem studies and tests are given for design of entry decelerators, high-g components, thermal control, data acquisition, and umbilical cable deployment.

Murphy, J. P.↗
NASA NTRS1981

Integrate oral communication with technical writing: Towards a rationale

Integrating oral communication and technical writing instruction, to give students the opportunity to learn and practice interpersonal skills, is proposed. By linking speech and writing the importance of small-group interaction in developing transferrable ideas is acknowledged. Three reasons for integration are examined: workday activities, application of role-taking to writing, and conflict resolution. Four advantages of integration are stated.

Skelton, T.↗
NASA NTRS1981

Float zone space processing rationale

The role of float zone silicon in integrated circuits is surveyed. The problem of oxygen thermal donors and their inhomogeneous distribution is predicted to be a critical issue.

Jastrzebski, L.↗
NASA NTRS1982

Workshop rationale

The problems involved in processing remotely sensed data are defined within the contex of the total information system structure. The correlation of various data sets through georeferencing and cataloging is emphasized along with geometric rectification. The sources and types of possible geometric errors are outlined.

Billingsley, F. C.↗
NASA NTRS1980

Rationale for evaluating a closed food chain for space habitats

Closed food cycles for long duration space flight and space habitation are examined. Wash water for a crew of six is economically recyclable after a week, while a total closed loop water system is effective only if the stay exceeds six months' length. The stoichiometry of net plant growth is calculated and it is shown that the return of urine, feces, and inedible plant parts to the food chain, along with the addition of photosynthesis, closes the food chain loop. Scenarios are presented to explore the technical feasibility of achieving a closed loop system. An optimal choice of plants is followed by processing, waste conversion, equipment specifications, and control requirements, and finally, cost-effectiveness.

Modell, M.↗
NASA NTRS1981

SETI - The search for extraterrestrial intelligence - Plans and rationale

The methodology and instrumentation of a 10 yr search for extraterrestrial intelligence (SETI) program by NASA, comprising 5 yr for instrumentation development and 5 yr for observations, is described. A full sky survey in two polarizations between 1.2 and 10 GHz with resolution binwidths down to 32 Hz, and a two polarization can between 1.2-3 GHz with resolution binwidths down to 1 Hz of 700 nearby solar type stars within 20 light years of earth will extend the sensitivity of previous surveys by 300 times and cover 20,000 times more frequency space. EM signals are perceived as the only means for detecting life outside the solar system, and the SETI effort is driven by the empirical experience that once a physical process has been observed to occur, its occurrence elsewhere is assured. Further discussion is given of the history of searches for life in the Universe, the SETI search strategy, instrumentation, and signal identification.

Wolfe, J. H.↗
NASA NTRS1984

Steps toward eight-meter honeycomb mirror blanks. I Rationale and approach

The best form for 8-m telescope mirrors is discussed. It is concluded that honeycomb sandwich structure can meet the most exacting demand goals for subarcsecond image quality in optical and infrared astronomy. These structures are light, have good stiffness against gravitational and wind loading, and have low thermal inertia. The latter permits them to be operated at the ambient air temperature to avoid local seeing problems. Borosilicate and aluminosilicate glasses are adequate materials for ventilated honeycombs, which do not require low expansion materials.

Angel, J. R. P.↗