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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 739 records · Page 41
All sourcesNASA NTRSDOE OSTI
NASA NTRS1964

Investigation and study of a multi-aperture antenna system final report, 1 jan. - 1 apr. 1964

This investigation was concerned with a multiple aperture adaptive antenna system for application to receiving telemetered data from remote space vehicles or satellites. The primary criterion for determining the feasibility of such a system has been economic considerations, but of necessity many physical constraints imposed on both a single antenna and a multiple aperture system have been evaluated. These include such factors as acquisition and combining of signals, look angle, shadowing, propagation influences system spatial bandwidth, collimation, interference, doppler effects, reliability, and noise. Specific conclusions have been made for a system operating at a frequency of 2 Gc, but the system model adopted allows quick evaluation at other frequencies. At a frequency of 2Gc, the crossover point between a single antenna or a multiple aperture configuration occurs for an 85 foot reflector. However this transition region is not critical. For lunar range communications a single antenna appears to be the most economical, whereas at interplanetary ranges aperture equivalents of around 400 feet are required and achieved by arraying eight 142 foot antennas.

TELEMETRY↗
NASA NTRS1967

Reusable Aerospace Passenger Transport - Study of Incremental Development Approaches Summary Report

This report summarizes the results of studies of economical orbital transportation systems, exploring, in particular , possible options for time - phases and incremental development of such systems. The major conclusions are : 1. Incremental development is a practical way for development of an economic logistics system, minimizing development risk and annual funding, and offering planning flexibility at only a nominal penalty in total systems cost. 2. The most promising first development appears to be that of a re- usable payload carrier with a capacity of 9 to 12 passengers. 3. Systems comparisons show that, for the foreseeable variations of the mission market, a partially reusable concept could bring about most of the program savings that can be expected from reusability at moderate development risk and funding rate. 4. A further development leading to a fully reusable system has high risk and uncertain payoff. Conceivably, at that time, a more advanced concept might be introduced.

Dietrich W Fellenz↗
NASA NTRS1970

Payload impact of space shuttle and tug

The advantages offered by space shuttle and tug for space operations are summarized. Economical transportation to a space station and operations in orbit; frequent sorties, with flexible scheduling, for experiment missions; and an economical and flexible replacement for conventional launchers are discussed. These advantages include many potential benefits for payload design, construction, and use.

Newell, H. E.↗
NASA NTRS1972

Study of solid rocket motors for a space shuttle booster. Appendix D: Recovery and reuse 156-inch diameter solid rocket motor booster

The baseline for a space shuttle configuration utilizing two parallel-burn, 156-in.-diameter SRMs with three segments and techroll seal movable nozzles is presented. The concept and general economic benefits of SRM recovery are equally valid for the series-burn SRMs, provided that those SRMs are also designed for the same strength, stiffness, segmentation, and interchangeability as the present design, and that those SRMs are also recovered as individual units. Feasibility studies were initiated to investigate SRM recoverability. These studies were based upon recovery of the SRM boosters for the Titan 3C. Ground rules precluded SRM modification that required significant changes in motor qualification or schedule. Even with this restriction, the study determined that the recoverable booster concept was completely feasible, both technically and economically. Parachute recovery has been selected as the best method, principally because it can accomplish the task with a minimum development cost and time to achieve operational recovery status. This system affords the highest probability for achieving large cost reductions.

Source record↗
NASA NTRS1972

Advanced small launch vehicle study

A conceptual design study was conducted to determine the most economical (lowest cost/launch) approach for the development of an advanced small launch vehicle (ASLV) for use over the next decade. The ASLV design objective was to place a 340 kg (750 lb) payload into a 556 km (300 n.mi.) circular orbit when launched due east from Wallops Island, Virginia. The investigation encompassed improvements to the current Scout launch vehicle; use of existing military and NASA launch vehicle stages; and new, optionally staged vehicles. Staging analyses included use of liquid, solid, and hybrid propellants. Improvements in guidance, controls, interstages, telemetry, and payload shroud were also considered. It was concluded that the most economical approach is to progressively improve the Scout launch vehicle in three phased steps which are discussed.

Reins, G. E.↗
NASA NTRS1972

Propulsion technology for an advanced subsonic transport

Engine design studies for future subsonic commercial transport aircraft were conducted in parallel with airframe studies. These studies surveyed a broad distribution of design variables, including aircraft configuration, payload, range, and speed, with particular emphasis on reducing noise and exhaust emissions without severe economic and performance penalties. The results indicated that an engine for an advanced transport would be similar to the currently emerging turbofan engines. Application of current technology in the areas of noise suppression and combustors imposed severe performance and economic penalties.

Beheim, M. A.↗
NASA NTRS1972

A look at V/STOL for business aircraft.

Attempt to ascertain the economic viability of the V/STOL capability for business aircraft and the manner in which this viability depends on the aircraft concept. A cost-benefit analysis is presented which indicates that a VTOL business aircraft would be more viable economically than a contemporary turbine-powered business aircraft. The combination of traveler's time value and trip distance for which each aircraft dominates is shown. The significance of disk loading in V/STOL concept application is discussed, and preliminary design configuration studies for three different business-aircraft-sized V/STOLs, using three concepts covering a range of disk loading, are presented as examples. Finally, a discussion of operational aspects of interest to future users of V/STOL business aircraft is presented which centers around the requirements for routine IFR terminal-area operations.

Feistel, T. W.↗
NASA NTRS1972

Advanced propulsion - Cleaner and quieter.

Studies were conducted to determine the factors which are significant in advancing propulsion technology. The studies surveyed a wide distribution of variables including aircraft configuration, payload, range, and speed. System studies placed major emphasis on reducing noise and exhaust emissions while attaining good economies and performance. An engine for an advanced transport will probably superficially resemble the presently emerging generation of modern high-bypass and high-temperature turbofan engines, but would incorporate the advances in component and system technology identified by the propulsion system studies. These advances could be used to improve aircraft economics significantly with no increase in noise, or to significantly reduce noise and pollution with few or no economic penalties.

Beheim, M. A.↗
NASA NTRS1972

RAM - A concept for reducing space payload costs.

The post-Apollo era in manned space flight will be dominated in the short term by development of the space shuttle as an economical transportation system for payloads to low earth orbit. Research and Applications Modules (RAM) are a related group of shuttle-launched carriers for such payloads which can be used many times over, thus effecting great savings over currently conventional methods of implementing a program of this type. In order to maximize the potential savings, development and unit costs of the RAM vehicles must be minimized. All of the mission and operating modes can be covered in an economical fashion by the use of only three basic RAM elements - a pressurized module, an unpressurized pallet, and a pressurizable free-flying unit utilized in several combinations. These have been developed as a least cost approach through the consideration of such cost/weight related drivers as available crew size, separability of costly subsystems for multiple use, easy accessibility for maintenance/refurbishment for reuse, and a maximum commonality of hardware with existing and projected space projects.

Powell, D. J.↗
NASA NTRS1972

Study of short haul high-density V/STOL transportation systems, volume 1

The relative advantages of STOL aircraft concepts were examined by simulating the operations of a short haul high-density intercity STOL system set in two arenas, the California corridor and the Chicago-Detroit-Cleveland triangle, during the 1980 time period. The study was constrained to the use of three aircraft concepts designated as the deflected slipstream turboprop, externally blown flap, and augmentor wing turbofan configurations. The projected demographic, economic, travel demand, and travel characteristics of the representative arenas were identified. The STOL airline operating scenarios were then formulated and through the use of the aerospace modal split simulation program, the traveler modal choices involving alternative STOL concepts were estimated in the context of the total transportation environment for 1980. System combinations that presented the best potential for economic return and traveler acceptance were then identified for each STOL concept.

Solomon, H. L.↗
NASA NTRS1971

Expendable second stage reusable space shuttle booster. Volume 1: Executive summary

The development of an expendable second stage for use with a reusable space shuttle booster is discussed. The configuration of a low-cost, reusable multipurpose space transportation system for the 1980 time period is presented. A system capable of economically placing payloads in earth orbit which are larger and heavier than can be carried in the shuttle orbiter cargo bay is defined. The ESS/reusable shuttle system is complementary to the space shuttle system and provides mission flexibility to permit economical expansion of the overall space program.

Source record↗
NASA NTRS1973

Conceptual design of a V/STOL lift fan commercial short haul transport

Conceptual designs of V/STOL lift-fan commercial short-haul transport aircraft for the 1980-85 time period were studied to determine their technical and economic feasibility. Engine concepts studied included both integral remote fans. The scope of the study included definition of the hover control concept for each propulsion system, aircraft design, aircraft mass properties, cruise performance noise, and ride qualities evaluation. Economic evaluation was also studied on a basis of direct operating cost and route structure.

Source record↗
NASA NTRS1972

Methods of determining electron concentrations in the magnetosphere from nose whistlers

Whistler propagation in the magnetosphere was studied in detail to find accurate and economical means of determining the path latitude and the electron concentration along the path from whistler parameters of nose frequency and travel time at the nose. Longitudinal propagation in field aligned whistler ducts of cold plasma was assumed, and the earth's magnetic field was approximated by a centered dipole. The effects of whistler propagation in the earth-ionosphere waveguide and through the conjugate ionospheres were treated as small perturbations. Several alternative methods are described so that the most economical method may be chosen depending on the desired accuracy and the availability of a computer or a calculator.

Park, C. G.↗
NASA NTRS1973

Conceptual design studies of candidate V/STOL lift fan commercial short haul transport for 1980 - 1985 V/STOL lift fan study

Conceptual designs of V/STOL lift fan commercial short haul transport aircraft for the 1980-85 time period were studied to determine their technical and economic feasibility. The engine concepts included both integral and remote fans. The scope of the study included definition of the hover control concept for each propulsion system, aircraft design, aircraft mass properties, cruise performance, noise and ride qualities evaluation. Economic evaluating was also studied on a basis of direct operating costs and route structure.

Eldridge, W. M.↗
NASA NTRS1973

Conceptual design study of a V/STOL lift fan commercial short haul transport

Conceptual designs of V/STOL lift fan commercial short haul transport aircraft for the 1980-85 time period were studied to determine their technical and economic feasibility. The engine concepts included both integral and remote fans. The scope of the study included definition of the hover control concept for each propulsion system, aircraft design, mass properties, cruise performance, noise and ride qualities evaluation. Economic evaluation was also studied on the basis of direct-operating costs and route structure.

Knight, R. G.↗
NASA NTRS1973

Quiet turbofan STOL aircraft for short haul transportation, volume 1

The characteristics for a quiet turbofan short takeoff aircraft for short haul transportation applications are discussed. The following subjects are examined: (1) representative aircraft configurations, characteristics, and costs associated with the short haul aircraft development and operation, (2) critical technology and technology related problems to be resolved in successful introduction of representative short haul aircraft, (3) relationships between quiet short takeoff aircraft and the economic and social viability of short haul, and (4) identification of high payoff technology areas. In order to properly evaluate the candidate aircraft designs and to determine their economic viability and community acceptance, a real world scenario was developed and projected to 1990.

Renshaw, J. H.↗
NASA NTRS1973

Study of unconventional propulsion system concepts for use in a long range transport

The noise level of an uncoventional propulsion system for the next generation of subsonic, long-range transport aircraft is discussed. The desired noise level may be achieved by: (1) a fixed geometry, high bypass ratio turbofan with a geared two-stage fan and advanced acoustic treatment or (2) a moderate bypass ratio turbofan with a variable pitch two-stage fan, variable primary and duct nozzles, and advanced acoustic treatment. The geared fan system meets the noise goal with minimum economic penalty. Comparison of the noise levels at takeoff and landing in combination with the economic penalties required to achieve the lower noise levels at specific noise measuring stations, indicate that both area reduction and current certification prodedures should be used to ascertain the point of diminishing returns in establishing future noise goals.

Champagne, G. A.↗
NASA NTRS1973

Feasibility of mining lunar resources for earth use: Circa 2000 AD. Volume 1: Summary

The feasibility of obtaining lunar minerals for terrestrial uses is examined. Preliminary results gave indications that it will not be economically feasible to mine, refine, and transport lunar materials to Earth for consumption. A broad systems approach was used to analyze the problem. It was determined that even though the procedure was not economically advisable, the concept for the operations is technically sound.

Nishioka, K.↗