Unsteady aerodynamic characteristics of a fighter model undergoing large-amplitude pitching motions at high angles of attackThe effects of harmonic or constant-rate-ramp pitching motions (giving angles of attack from 0 to 75 deg) on the aerodynamic performance of a fighter-aircraft model with highly swept leading-edge extensions are investigated experimentally in the NASA Langley 12-ft low-speed wind tunnel. The model configuration and experimental setup are described, and the results of force and moment measurements and flow visualizations are presented graphically and discussed in detail. Large force overshoots and hysteresis are observed and attributed to lags in vortical-flow development and breakup. The motion variables have a strong influence on the persistence of dynamic effects, which are found to affect pitch-rate capability more than flight-path turning performance.
Document ID
19900039878
Acquisition Source
Legacy CDMS
Document Type
Conference Paper
Authors
Brandon, Jay M. (NASA Langley Research Center Hampton, VA, United States)
Shah, Gautam H. (NASA Langley Research Center Hampton, VA, United States)