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The paper gives an overview of the propulsion content of the programs at the undergraduate and postgraduate levels, as offered to students in both Mechanical and Aerospace Engineering.

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.

To achieve this goal, NASA has analyzed a hybrid body wing aircraft with a turboelectric distributed propulsion system. The propulsion system must be designed to operate at the highest possible efficiency in order to meet the reduced fuel burn goal. ...High density components are required to minimize the weight of the electric propulsion system while meeting the high power demand. Minimizing the electric propulsion system weight helps to reduce the amount of fuel required for propulsion. ...NASA's N3-X aircraft design under the Research and Technology for Aerospace Propulsion Systems (RTAPS) study is being designed to meet the N+3 goals, one of which is the reduction of aircraft fuel burn by 70% or better.

To present methods which, according to the consensus of the aviation propulsion community represented by SAE Committee E-34, allow the continued assessment of load carrying capacity of current chemistry products during periods of limited or nonavailability of previously used standardized methods.

As a result, UAV research and development will contribute to a major portion of spending in the next decades—with a significant emphasis on propulsion technologies. This book will cover several UAV propulsion technologies, ranging from modification of conservative designs to assessing the potential of unconventional arrangements. ...Each chapter provides a glimpse of how researchers are leveraging different fuel types, powerplants, and system architectures in the pursuit of powerful, efficient, and robust UAV propulsion. By developing higher-performing propulsion systems—whether through the refinement of existing technologies like two-stroke heavy-fuel engines and hybrid-electric arrangements or the investigation of new concepts such as dielectric barrier discharge—engineers will be able to increase UAV capabilities for the world’s developing aviation needs.

Propulsion system hardware has steadily increased in complexity which has placed even greater demands on the propulsion control hardware. ...Propulsion system hardware has steadily increased in complexity which has placed even greater demands on the propulsion control hardware. With the engine and inlet operating at higher levels of performance, the need for improvements in control system technology has become more evident. ...In addition to increased sensing and computation, it is required that the various inlet and engine control functions be integrated to achieve maximum propulsion system stability and performance during all flight conditions. This paper describes a three year exploratory research program for the design, development, and flight evaluation of an Integrated Propulsion Control System (IPCS).

The general problem of applying propulsion systems to supersonic aircraft is discussed briefly and it is shown that neither turbojets nor ramjets are entirely satisfactory when used by themselves. ...In order to avoid the confusion resulting from the comparison of propulsion system performance using the special parameters associated with each type of engine, performance is compared along operating altitude-Mach number paths in terms of thrust and specific fuel consumption only. ...The combined propulsion system arrived at offers promise of good performance, light weight, low cost, and simple installation.

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.

The goal of the propulsion community is to have the enabling propulsion technologies in place to permit a low risk decision regarding the initiation of a research STOVL supersonic attack/fighter aircraft in the mid-1990's. ...This program, the Supersonic STOVL Integrated Flight-Propulsion Controls Program, is part of the overall NASA Lewis Supersonic STOVL Propulsion Technology Program, it uses an integrated approach to an integrated program to achieve integrated flight-propulsion control technology.

This paper presents the overall scope of the NASA Lewis High Performance Aircraft Propulsion Research Program. High performance fighter aircraft of interest include supersonic fighters with such capabilities as short takeoff and vertical landing (STOVL) and/or high maneuverability. ...The NASA Lewis effort involving STOVL propulsion systems is focused primarily on component-level experimental and analytical research. ...The overall objective of the NASA Inlet Experiments portion of the HATP, which NASA Lewis leads, is to develop and enhance inlet technology that will ensure high performance and stability of the propulsion system during aircraft maneuvers at high angles of attack. To accomplish this objective, both wind-tunnel and flight experiments are used to obtain steady-state and dynamic data, and computational fluid dynamics (CFD) codes are used for analyses.

This paper presents (1) a chronology of Air Force technical activity on future propulsion concepts, (2) a status report on NASA research on scramjet technology for future systems which may require speeds above Mach 5, and (3) a description of a research vehicle by which advanced propulsion technology and other technologies related to high speed can be demonstrated. ...This paper presents (1) a chronology of Air Force technical activity on future propulsion concepts, (2) a status report on NASA research on scramjet technology for future systems which may require speeds above Mach 5, and (3) a description of a research vehicle by which advanced propulsion technology and other technologies related to high speed can be demonstrated.

During the 1970's, our hypersonic effort dwindled to a few dedicated research efforts which refined propulsion, aerodynamics, and computational fluid dynamics principles. To make real progress in the 1980's, and beyond, a focus and a rekindled effort was needed. ...The primary emphasis of the paper is National Aero-Space Plane propulsion technology. Key technical challenges are noted and a discussion of progress relative to those challenges associated with propulsion is presented. ...Key technical challenges are noted and a discussion of progress relative to those challenges associated with propulsion is presented.

A multimode propulsion control system concept has been developed for the remotely piloted research vehicle of the NASA Highly Maneuverable Aircraft Technology program.

We analyse 635 set-years of service experience of 147 merchant-marine steam-turbine-gear propulsion sets, finding an MTBF of 23.5 set-years. The sets of one good-sized fleet have 3 times as large an MTBF as the rest of the sample, a fine return on the more conservative attention paid them.

Future propulsion programs that are required for the United States to reach a competitive position in the advanced supersonic commercial airplane market are also reviewed.

Circulation control wing (CCW) technology has been in the research and development phase for over sixty years with a minimal amount of practical applications to subsonic transport aircraft. The concept is based on the use of high pressure Coanda jet air that is diverted from the fan or compressor of the main turbofan engines; however, this can create a significant decrease in engine performance. This paper will provide the background of past CCW research and conclude with recommendations for a conceptual design for a circulation control wing that implements multiple, lightweight gas generators, which are separate from the main aircraft engines that provide high pressure air or exhaust gas to the wing leading and trailing.

This paper briefly reviews the objectives and status of the propulsion portion of the program. Building upon a continuing series of propulsion system studies, research activities are under way in noise and pollution reduction, inlet stability, and materials.

Recent developments in sonic inlet technology are presented with particular emphasis on STOL propulsion systems. Inlet noise reduction requirements are discussed for an augmentor wing and an upper surface blowing type of propulsion system. ...Inlet noise reduction requirements are discussed for an augmentor wing and an upper surface blowing type of propulsion system. The current state of the art is discussed with respect to performance and noise potential of different sonic inlet concepts.

The Propulsion Aerodynamics Branch (and its predecessors) at the NASA Langley Research Center has been conducting propulsion aerodynamics research since 1941. ...The Propulsion Aerodynamics Branch (and its predecessors) at the NASA Langley Research Center has been conducting propulsion aerodynamics research since 1941. During that time, branch research has had an impact on almost every aircraft flown.