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THE NUCLEAR turboelectric ion propulsion system operates as follows: 1. A nuclear reactor supplies thermal energy to a vapor boiler. 2. ...Electric propulsion systems can be used in a wide variety of space missions, including satellite sustainers, lunar cargo transport, and interplanetary missions.*

This paper reviews a recent internal study by Pratt & Whitney to define the optimum propulsion system characteristics for a commercial transport designed to fly at Mach 0.95. The impact on aircraft gross weight of propulsion cycle characteristics such as bypass ratio, overall pressure ratio, turbine temperature, nacelle weight, and drag as well as the important criteria of noise is reviewed. ...The impact on aircraft gross weight of propulsion cycle characteristics such as bypass ratio, overall pressure ratio, turbine temperature, nacelle weight, and drag as well as the important criteria of noise is reviewed.

This paper will identify some of the primary propulsion integration problems for high performance aircraft at transonic speeds, and demonstrate several methods for reducing or eliminating the undesirable characteristics, while enhancing configuration effectiveness.

It is compared with the chemical rocket and the nuclear turboelectric ion propulsion system. In developing the concept for this low-power rocket, NASA engineers concentrated on attaining low weight and high hydrogen temperature, and on solving problems concerned with automatic control and operation of high-temperature reactors.

Measurements of the gas state properties in hypersonic propulsion system research present unique problems demanding unconventional diagnostic measurement system design solutions.

General aviation of the middle 1980's has been less than inspiring from a business viewpoint. Numerous aerodynamic innovations have matured, however, little progress has been made in powerplants. Although significant technology exists for powerplant design progress, low demand and product liability concerns have supressed implementation. The Merlyn design represents one of several present efforts to provide a particular technology to address specific needs in the aviation marketplace.

A landmark study of Synerjet propulsion for fully-reusable Earth/orbit transport missions was conducted for NASA in 1965-67 by a study team of Marquardt, Rocketdyne, and Lockheed (the present author led this effort). ...Synerjet propulsion systems are fully integrated aerospace vehicle power-plants, comprising both airbreathing and rocket hardware subsystems and technologies.

The requirements of engine test cells and propulsion laboratories for propulsion education will be discussed. A typical versatile propulsion laboratory set-up for testing full-scale aircraft reciprocating engines, gas turbines, as well as small-scale rocket motors will also be presented. ...There are a variety of propulsion packages available for general aviation aircraft including reciprocating engines, small gas turbines, and rotary engines. ...In future, electrical propulsion will be a major contender in this market. The importance of general aviation propulsion education for aeronautical engineers will be addressed.

A trade study comparing the overall benefits in placing large payloads to GEO with the nuclear electric propulsion option shows superiority of nuclear thermal propulsion. The resulting savings in orbital transfer time and the substantial reduction of overall lift requirement enables the use of low-cost launchers for several near-term military satellite missions. ...An integral space power concept provides both the electrical power and propulsion from a common heat source and offers superior performance capabilities over conventional orbital insertion using chemical propulsion systems. ...An integral space power concept provides both the electrical power and propulsion from a common heat source and offers superior performance capabilities over conventional orbital insertion using chemical propulsion systems. This paper describes a hybrid (bimodal) system concept based on a proven, inherently safe solid fuel form for the high temperature reactor core operation and rugged planar thermionic energy converter for long-life steady state electric power production combined with NERVA-based rocket technology for propulsion.

The author discusses the ADAM II (Air Deflection and Modulation) propulsion system as it is applied to LTV propulsive wing airplane configurations which house all or part of their propulsion system within the wing surface. ...The author discusses the ADAM II (Air Deflection and Modulation) propulsion system as it is applied to LTV propulsive wing airplane configurations which house all or part of their propulsion system within the wing surface. Briefly mentioned are the original ADAM I configuration and its subsequent development to the present ADAM II, together with a discussion of the characteristics currently used for each of its components such as fan turbine set, gas generator, hot gas ducting, wing mounted turbofans, and mechanical cross shafting. ...The ADAM II concept is applicable to a full spectrum of subsonic aircraft and the propulsion system uses present day state-of-the-art technology which makes the feasibility of its development quite real.

Wide scope systems studies of V/STOL propulsion were conducted by GE, encompassing the total air vehicle design and its operation in lift, transition, cruise, and STOL modes. ...To determine VTOL propulsion requirements, the author explains the necessity for incorporating the entire air vehicle into the analysis. ...It is felt that the performance indicated necessary by these studies is now attainable by the propulsion industry.

Previous papers in this session described the historical aspects, tradeoffs, and requirements for powered lift propulsion systems, and it is shown that propulsion technology is more key to the success of this type of aircraft than for any previous fighter/attack aircraft. ...This paper discusses the NASA Lewis Research Center program activities which address required propulsion technology development. Several elements of this program have been initiated which address hot gas ingestion and ejector augmenter performance and some preliminary results are shown.

Investigation into electric propulsion continues to be an area of hopeful research since the pioneering age of aviation. However, more recent global awareness of carbon emissions on the planet and the desire to create more efficient systems has reinvigorated new life into the field. ...Experimental studies on electric propulsion by virtue of asymmetrical electrodes, on a micro scale, have yielded potentially superior efficiency ratings when compared to currently adopted methods. ...This method of propulsion is unique and possesses several features that differentiate it from conventional methods of propulsion.

Two propulsion related drag correlation parameters have been developed. Existing or planned parametric jet aftbody drag data can therefore be reduced into a simple prediction technique for aircraft preliminary design studies. ...The drag due to the external nozzle geometry correlates with the average slope of the aftbody's area distribution (Integral Mean Slope), and the drag influence of the internal nozzle geometry/exhaust plume correlates with an effective plume inclination angle (Plume Correlation Parameter). The propulsion related drags of single, twin, and two-dimensional jet installations, and convergent, convergent-divergent, and plug nozzles are shown to correlate with the two parameters.

The Waste Management/Rocket Propulsion System appears capable of satisfying many propulsion requirements; for example, orbit change maneuvers, aerodynamic drag makeup, midcourse correction, terminal braking, and auxiliary and emergency propulsion. ...To date, spacecraft designers have considered life support systems and rocket propulsion systems as independent subsystems of a manned spacecraft. The Integrated Waste Management/Rocket Propulsion System concept developed by Rocket Research Corp. under NASA Contract NAS 1–6750, has demonstrated that human waste products can form a useful propellant ingredient and provide propulsion, as well as be an effective means of removing and sterilizing spacecraft waste. ...The Integrated Waste Management/Rocket Propulsion System concept developed by Rocket Research Corp. under NASA Contract NAS 1–6750, has demonstrated that human waste products can form a useful propellant ingredient and provide propulsion, as well as be an effective means of removing and sterilizing spacecraft waste.

The purpose of this paper is to identify some of the constraints imposed on an airplane propulsion system by transonic cruise speeds and to explore some ways to satisfy them. As the design Mach number of an airplane is increased above the 0.85 level toward 1.0, good airplane performance depends increasingly on careful tailoring of the propulsion installation and its integration into the overall configuration to establish a good compromise between drag, internal nacelle performance, and the practical considerations that produce an excellent airplane. ...As the design Mach number of an airplane is increased above the 0.85 level toward 1.0, good airplane performance depends increasingly on careful tailoring of the propulsion installation and its integration into the overall configuration to establish a good compromise between drag, internal nacelle performance, and the practical considerations that produce an excellent airplane.

Hydrocarbon fuels capable of meeting high performance standards in advanced supersonic propulsion systems can be produced in substantial volume at reasonable cost from petroleum streams by hydrogenating aromatic concentrates or processing certain cuts from selected crudes.

Current activities in seals for space propulsion turbomachinery that the NASA Lewis Research Center sponsors are surveyed. The overall objective is to provide the designer and the researcher with the concepts and the data to control seal dynamics and leakage.

A decentralized, multivariable controls methodology is being developed for the functional integration of a fighter's aerodynamic controls with those of its propulsion system (inlet, engine, and thrust vectoring/reversing nozzle). Integrated controls account for, and take advantage of the significant cross-coupling between these system elements.

The application of air breathing turbofan engines to a variable geometry, lifting, entry spacecraft provides a Cruise-spacecraft having increased operational flexibility. This spacecraft can accomplish a high performance, 3000 nautical mile lateral range mission, by combining the glide available from its medium hypersonic L/D (1. 7 to 2. 3) with subsonic cruise in the atmosphere. In this application, it excels low L/D spacecraft requiring orbit maneuvers to enhance lateral range. It is competitive with high L/D spacecraft while avoiding some of their advanced aerodynamic and thermal protection system technologies. For the reduced lateral range logistic mission, the spacecraft can utilize the “liquid L/D” principle to reduce cruise fuel and replace it with additional cargo. The Cruise-spacecraft is a medium L/D, slim, lifting body which uses an ablative lower surface and a radiative upper surface for protection during entry.