Wind-Tunnel Investigation of the F-16 Transonic Buffet Phenomenon

The paper presents an experimental study of the shock buffet phenomenon based on wind tunnel tests of a rigid F-16 model with various store configurations. Unsteady dynamic pressure data, collected under transonic flow conditions, enabled the identification and mapping of the buffet envelope in terms of Mach number and angles of attack. The study characterizes the phenomenon and compares it with that observed in transport aircraft. Analysis of unsteady pressure data revealed significant fluctuations associated with shock motion and flow separation. Spectral techniques were applied to identify dominant frequencies associated with the buffet. A comparative investigation among different external store configurations assessed their impact on wing buffet characteristics using signal post-processing and visualization techniques. The results indicate that the presence of external stores affects the buffet’s angle of attack and Mach number boundaries, as well as its onset and offset trends, although their effect on frequency variation was minimal. The identified buffet characteristics aligned well with F-16 flight test data in terms of buffet frequency. Overall, the study’s findings support the potential of using wind tunnel test data to model unsteady aerodynamics for predicting buffet loads on fighter aircraft wings.