Emerging Federal Regulatory Framework For Future Supersonic Transport Aircraft

Supersonic transports will require jet-engine thrust nozzles that are highly efficient from take-off to supersonic cruise in order to minimize the direct operating costs. Variable-area ejectors, plug nozzles, and modifications of these basic types have been tested extensively during the past several years. Performance trends for these nozzles are presented with the emphasis on external flow effects. A new ejector which utilizes aerodynamically actuated doors to admit external air into the ejector shroud is discussed.

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Propelling Nozzle Research

Journal of the Royal Aeronautical Society ◽

10.1017/s0368393100080834 ◽

1964 ◽

Vol 68 (647) ◽

pp. 717-727 ◽

Cited By ~ 2

Author(s):

W. G. E. Lewis

Keyword(s):

High Speed ◽

High Performance ◽

Research Programme ◽

Static Tests ◽

Transport Aircraft ◽

Supersonic Transport ◽

Design Behaviour ◽

Base Bleed ◽

Critical Phases ◽

The Ideal

SummaryThe current interest in supersonic transport aircraft makes it appropriate to consider the problems of propulsion nozzle systems for high speed flight. The discussion will be confined mainly to this field of activity.In the absence of external drag and weight factors, the ideal configuration to maintain optimum thrust at all flight speeds would employ a mechanically variable area ratio nozzle. By such means the jet flow could be fully and properly expanded at all times.A practical design to accommodate such variations is inherently complex, and so an alternative solution using aerodynamic techniques has been sought. It is necessary to remember that the success of whatever method is eventually chosen must rest on its ability to combine a high performance at cruise with very small loss during other critical phases of the flight plan.This paper describes some of the results of a nozzle research programme aimed primarily at solving the above problem, with an attempt to explain the philosophy behind the aerodynamic techniques tried. Some discussion is given of the experimental difficulties in establishing a sufficiently accurate standard of measurement for design point performance. In a few chosen configurations experimental results have been extensively backed by theoretical studies.The need to demonstrate off-design behaviour in the presence of an external flow field is stressed, with special reference to the misleading results often obtained from static tests.Finally, some attention is given to the question of base bleed, with its repercussions on the installation of the propulsion nozzle in an aircraft.

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Separation Standards and Aircraft Wander

Journal of Navigation ◽

10.1017/s0373463300047214 ◽

1966 ◽

Vol 19 (2) ◽

pp. 198-208

Author(s):

R. N. Lord

Keyword(s):

Block Size ◽

Physical Size ◽

Transport Aircraft ◽

Supersonic Transport ◽

Sources Of Error ◽

Forward Prediction ◽

Basic Parameters ◽

Corrective Control ◽

Separation Standards ◽

Along Track

The basic parameters leading to aircraft navigational error are combined statistically and are used to evaluate the uncorrected deviation (wander) to be expected in both subsonic and supersonic transport aircraft operating in a typical trans-oceanic environment. The size of the across-track and along-track wander before any form of corrective control is applied indicates the physical size of the A.T.C. block of airspace necessary to contain the aircraft. The variation of block size with the forward prediction period used by A.T.C. is presented graphically. The effect of improvement in the basic sources of error is demonstrated and it is seen that for the S.S.T. era attention must be turned to effecting improvements in aircraft heading and airspeed holding capabilities.

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