Accession Number : ADP006219

Title :   A Unified Approach to Buffet Response of Fighter Aircraft Empennage,

Corporate Author : MCDONNELL AIRCRAFT CO ST LOUIS MO

Personal Author(s) : Ferman, M. A. ; Patel, S. R. ; Zimmerman, N. H. ; Gerstenkorn, Gordon

Report Date : SEP 1990

Pagination or Media Count : 18

Abstract : A unified approach has been derived from predicting buffet response of fighter aircraft empennage operating in high angle of attack maneuvering conditions. Since the advent of high angle of attack flight using controlled vortex flows, incidences of severe structural stress, and in some cases, damages have resulted. This has been pronounced on twin tailed aircraft, including McDonnell's F-15 and F/A-18 aircraft which require structural beef-ups to their empennage. Two concepts are shown for predicting buffet response of empennage. The first approach uses elastically scaled models in wind tunnel tests to provide full scale prediction. The second approach is based on calculations using measured pressure data from wind tunnel tests. The latter method is more versatile. Detailed applications are shown for the F/A-18 empennage, while other applications at McDonnell are noted.

Descriptors :   *BUFFETING, *TAIL ASSEMBLIES, *TURBULENT FLOW, JET FIGHTERS, FLIGHT MANEUVERS, VORTICES, ANGLE OF ATTACK, HIGH ANGLES, STRUCTURAL RESPONSE, MATHEMATICAL PREDICTION, WIND TUNNEL TESTS, EXPERIMENTAL DATA.

Subject Categories : Aerodynamics
      Attack and Fighter Aircraft

Distribution Statement : APPROVED FOR PUBLIC RELEASE