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Nonlinear feedback control for high alpha flightAnalytical aerodynamic models are derived from a high alpha 6 DOF wind tunnel model. One detail model requires some interpolation between nonlinear functions of alpha. One analytical model requires no interpolation and as such is a completely continuous model. Flight path optimization is conducted on the basic maneuvers: half-loop, 90 degree pitch-up, and level turn. The optimal control analysis uses the derived analytical model in the equations of motion and is based on both moment and force equations. The maximum principle solution for the half-loop is poststall trajectory performing the half-loop in 13.6 seconds. The agility induced by thrust vectoring capability provided a minimum effect on reducing the maneuver time. By means of thrust vectoring control the 90 degrees pitch-up maneuver can be executed in a small place over a short time interval. The agility capability of thrust vectoring is quite beneficial for pitch-up maneuvers. The level turn results are based currently on only outer layer solutions of singular perturbation. Poststall solutions provide high turn rates but generate higher losses of energy than that of classical sustained solutions.
Document ID
19910000734
Acquisition Source
Legacy CDMS
Document Type
Contractor Report (CR)
Authors
Stalford, Harold
(Georgia Inst. of Tech. Atlanta, GA, United States)
Date Acquired
September 6, 2013
Publication Date
April 1, 1990
Subject Category
Aircraft Design, Testing And Performance
Report/Patent Number
NAS 1.26:186545
NASA-CR-186545
Report Number: NAS 1.26:186545
Report Number: NASA-CR-186545
Accession Number
91N10047
Funding Number(s)
CONTRACT_GRANT: NAG1-959
Distribution Limits
Public
Copyright
Work of the US Gov. Public Use Permitted.
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