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The military necessity for supersonic aircraft to perform subsonic, high-performance maneuvers and to deploy between continents places demands upon propulsion systems which are ineptly met with currently available engine designs. Thrust requirements for modern supersonic aircraft are met with engines having airflow schedules differing widely from the airflow available from inlet designs. ...The thrust losses making up this drag fraction are considered to be those associated with the free stream area defined by the design-point inlet capture area, so that propulsion system performance can be analyzed and assessed effectively. Current design techniques to minimize transonic thrust losses throughout the propulsion system (including the inlet, engine, and exhaust systems) involve reducing maximum engine airflow at the supersonic design-point below potential design limits, resulting in propulsion system weight and supersonic maneuverability penalties. ...Current design techniques to minimize transonic thrust losses throughout the propulsion system (including the inlet, engine, and exhaust systems) involve reducing maximum engine airflow at the supersonic design-point below potential design limits, resulting in propulsion system weight and supersonic maneuverability penalties.

Each vehicle concept uses the propulsion system to provide a substantial portion of the low speed aerodynamic lift. This fact makes engine dynamic performance have a strong influence on the handling qualities and performance of the aircraft, as does the aerodynamics on the proper engine cycle for the best mission performance. ...To preclude this oversight, the airlines' powerplant requirements are discussed from an airline point of view with major emphasis placed on propulsion subsystem design responsibility, engine selection, thrust deterioration, and maintainability.

This paper presents a comparison between different hypotheses of propulsion of a spherical UAS. Different architectures have been analyzed assessing their specific aerodynamic, energetic, and flight mechanics features.

The flow around the nacelles of high altitude airships is very important in order to assess the inlet conditions and losses associated to their propulsion systems. The aerodynamics prediction of low Re number flows is a problem usually associated to the lack of accuracy of most of the turbulence models in everyday use.

In order to establish a propellant depletion system for propulsion shutdown on the Atlas space launch vehicle, design criteria have been closely examined to meet the unique environmental requirements in this particular application.

The mission requirements laid down in 1968 for advanced Air Force and Navy air superiority fighters dictated a quantum step forward in performance of their propulsion systems, particularly in terms of thrust-to-weight ratio and inlet-engine compatibility.

Recently several researchers have proposed utilizing the DBD in various configurations to act as viable propulsion systems for micro and nano aerial vehicles. The DBD produces stable atmospheric-pressure non-thermal plasma in a thin sheet with a preferred direction of flow. ...Several researchers have utilized DBDs in an annular geometric setup as a propulsion device. Other researchers have used them to alter rectangular duct flows and directional jet devices.

One aspect of supersonic transport propulsion system behavior which has been particularly difficult to predict is transient interaction between engine and inlet. ...Use of the Dynasar technique is illustrated by an example involving the effect of engine inflow turbulence on supersonic propulsion system transient performance.

A summary of information on airplane aerodynamics, ground effects, propulsion system aerodynamics, stability and control, and flying qualities of jet V/STOL airplanes - both direct jet lift and lift fan configurations is presented. ...Experimental research on propulsion aerodynamics in the hovering and very low speed ranges of flight. 3. Flight-test experience on the flying qualities of several jet V/STOL airplanes.

To take full advantage of this potential to improve air combat and attack effectiveness, a degree of coupling between the airplane's flight control system and its propulsion control system was investigated. It was demonstrated in manned simulation that integrating the Vectored Lift Fighter's powerful aerodynamic deceleration control with the control of its high thrust-to-weight ratio propulsion system effectively reduced pilots' work load during critical moments in air combat and attack maneuvers when the pilots' attention must be concentrated upon acquiring and tracking the target. ...It was demonstrated in manned simulation that integrating the Vectored Lift Fighter's powerful aerodynamic deceleration control with the control of its high thrust-to-weight ratio propulsion system effectively reduced pilots' work load during critical moments in air combat and attack maneuvers when the pilots' attention must be concentrated upon acquiring and tracking the target.

A vehicle concept was developed to demonstrate the ability of near term aeromechanics and propulsion technology to support such a system. The vehicle was composed of two stages. The system takes off horizontally and both stages return to a horizontal landing. ...Turbojet, ramjet, and rocket propulsion is used. The sensitivity of the system to thrust, drag, weight, and staging Mach number was examined.

Integration of propulsion and flight-control systems will provide significant performance improvements for supersonic transport airplanes. ...Improved inlet pressure recovery and decreased inlet drag can result from inlet control system integration. Using propulsion system forces and moments to augment the flight-control system and airplane stability can reduce the flight-control surface and tail size, weight, and drag.

For optimum propulsion system performance, minimum external drag must be consistent with maximum internal pressure recovery. ...Both inlet types have a place in the mission spectrum that can be envisioned for air-breathing propulsion systems.

Much of this improved performance will be directly related to propulsion system advances. In particular, multiaxis thrust vectoring nozzles have the potential of providing substantial airplane performance gains or even providing new capabilities. ...Because of the large benefits of multiaxis thrust vectoring, the Propulsion Aerodynamics Branch of the NASA Langley Research Center has conducted an extensive experimental research program in this area.

Among these are its aerodynamics, propulsion system, structural concept, materials, avionics and passenger seat. Advanced technology in the 340 design will result in a quality airliner better able to provide economical, reliable service with greater passenger comfort.

A preliminary analysis has been performed which predicts the propulsion performance gains to be realized by installing a stator in the wake of a typical light airplane propeller.

Analyses are based upon a set of baseline aircraft models which can be modified through a carefully selected set of parameters related to weight, aerodynamics, propulsion, economics, and mission. The software is intended to become one of the models that comprise the Aviation System Analysis Capability (ASAC) currently being developed by NASA under the Advanced Subsonic Technology (AST) program.

The discussion concentrates on farfield techniques and is limited to low Mach number, steady flows in the absence of active systems such as surface blowing and propulsion. The calculation techniques are applied to three-dimensional flow field solutions obtained with potential and Euler codes.

The higher fidelity model enables more accurate and general aerodynamic propulsion and weight computations with less reliance on regression methods and estimations. This paper focuses on the improvements that can enhance the state of the art in general aviation aircraft synthesis.

Significant advances applicable to vertical and short take-off and landing (V/STOL) aircraft have been made in aerodynamic, propulsion, composite structure and avionics technologies. These have been incorporated into the AV-8B Weapon System, whose performance has been demonstrated through the YAV-8B prototype flight program.