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This document is intended to serve as suitable guidance for propulsion system manufacturers and applicants for propulsion system type certification. It is also intended to provide guidance for subsequent propulsion system integration into aircraft systems for aircraft certification and operational use. ...The purpose of this SAE Aerospace Information Report (AIR) is to provide guidance for aircraft engine and propeller systems (hereafter referred to as propulsion systems) certification for cybersecurity. Compliance for cybersecurity requires that the engine control, propeller control, monitoring system, and all auxiliary equipment systems and networks associated with the propulsion system (such as nacelle systems, overspeed governors, and thrust reversers) be protected from intentional unauthorized electronic interactions (IUEI) that may result in an adverse effect on the safety of the propulsion system or the airplane. ...Compliance for cybersecurity requires that the engine control, propeller control, monitoring system, and all auxiliary equipment systems and networks associated with the propulsion system (such as nacelle systems, overspeed governors, and thrust reversers) be protected from intentional unauthorized electronic interactions (IUEI) that may result in an adverse effect on the safety of the propulsion system or the airplane.

This document applies to prognostics of aerospace propulsion systems. Its purpose is to define the meaning of prognostics in this context, explain their potential and limitations, and to provide guidelines for potential approaches for use in existing condition monitoring environments.

This Aerospace Information Report (AIR) presents metrics for assessing the performance of diagnostic and prognostic algorithms and systems delivering propulsion health management functions.

This paper explores some of the many considerations which enter into the choice of a specific spacecraft propulsion system for a particular application. The environment and its influence on propulsion requirements are discussed in general terms, characteristics of several propellant combinations are presented and an example of a typical ambitious mission is used. ...A general conclusion is that the state of the art of spacecraft propulsion technology must advance on a broad front in the time period prior to project definition in order to provide the technological options which allow significant optimization of the complete project propulsion system. ...A general conclusion is that the state of the art of spacecraft propulsion technology must advance on a broad front in the time period prior to project definition in order to provide the technological options which allow significant optimization of the complete project propulsion system.

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 SAE Aerospace Information Report (AIR) provides guidelines to document the functional and physical interface requirements for the electrical systems (including an Electronic Engine Control System (EECS) and its components) between a given propulsion system and the aircraft on which the system is installed. The Interface Control Document (ICD) is considered to be a subset of the Engine Installation Manual, with interface considerations between the Airframer and Engine manufacturer.

Optimization of a Prop-Fan propulsion system for a Mach 0.8, 120 passenger commercial transport has shown the need for relatively high levels of overall pressure ratio, combustor exit temperature, propeller tip speed and propeller disk loading to achieve lowest fuel burn and direct operating costs. ...Comparison of this optimized Prop-Fan propulsion system with an equivalent technology turbofan showed it to have significant mission fuel burn and direct operating cost advantages.

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.

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.

This objective translates directly to all parts of the launch vehicle system but especially propulsion. Rocketdyne is meeting this challenge today by designing an engine system which can be produced at one-tenth the cost of the current Space Shuttle Main Engine.

This paper describes the initial results of applying two machine-learning-based unsupervised anomaly detection algorithms, Orca and GritBot, to data from two rocket propulsion testbeds. The first testbed uses historical data from the Space Shuttle Main Engine.

ATR with extended precooling (Tout=100K) is examined in more detail. For propulsion systems including different types of engines, running simultaneously the concept of LH2 heat sink capacity concentration for turbojet air precooling is proposed.

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.

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.

In developing a modern commercial aircraft, the airframe and engine manufacturers work as a team to develop the propulsion system and verify the high standards of safety, reliability, and performance the airlines and the public expect. ...An extremely important part of this undertaking is the testing of the propulsion system components and finally the entire system in realistic simulated operating conditions before the airplane goes into service.

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.

These considerations will impose additional requirements on the propulsion system and, if not dealt with early in the design process, may compromise the total performance of the aircraft. ...The effects of these requirements on the sizing of the reaction control system and the propulsion system will be illustrated by a design example. How control authority requirements may affect the overall aircraft sizing will also be illustrated.

Surface tension principles applicable to the design of propellant management devices for static retention and dynamic control of space propulsion system propellants are discussed. The characteristics of ideal propellant retention and control (management) systems are introduced as criteria for judging proposed designs.

Particular emphasis is placed on: The role of simulation in system development, Software development and configuration control, Adaptation of the propulsion control system to a series of test facilities. Based on the experience acquired in the successful completion of the program, conclusions relevant to future engine/airframe development are drawn -- digital electronic engine controls are practical and essential for the fully integrated aircraft of the future.

This paper describes the methods used for the performance modeling, which includes propulsion modeling methods and flight test procedures. The resulting flight test data are presented.