CHARACTERISTICS OF THE SURFACE PRESSURES ON A F A-18 VERTICAL PIN DUETO BUFFET/

A wind-tunnel investigation of the characteristics of the surface pres sures 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) 1.5-m trisonic blowdown wind tunnel. The measurements were carrie d out by means of 48 fast response pressure transducers installed dire ctly 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 t he broadband eddy scale and convection pattern of the pressure field. The buffet loads were calculated from summation of the pressure signal s on the vertical fin surfaces. Spectral analyses and probability dens ities were evaluated to provide statistical information on the charact eristics of the buffet loads.