Characteristics of the surface pressures on a F/A-18 vertical fin due to buffet

A wind-tunnel investigation of the characteristics of the surface pressures on the vertical fin of a rigid 6% scale model of the F/A-18 due to buffet has been conducted in the Institute for Aerospace Research (IAR) 1.5m trisonic blowdown wind tunnel. The measurements were carried out by means of 48 fast response pressure transducers installed directly opposite to each other on the fin surfaces. Time-averaged and rms pressure distributions at various angles of attack were determined to investigate the behavior of the pressures on the fin surfaces. Space-time correlations of the transducer signals were performed to obtain the broadband eddy scale and convection pattern of the pressure field. The buffet loads were calculated from summation of the pressure signals on the vertical fin surfaces. Spectral analyses and probability densities were evaluated to provide statistical information on the characteristics of the buffet loads. Nomenclature Aj = area of ;th panel on vertical fin AT = total surface area of fin