Wing Jet Blowing on the Subsonic High Alpha Research Concept Fighter Configuration

Abstract

A large-scale experimental investigation using the 55%-scale Subsonic High Alpha Research Concept (SHARC) was performed in the NASA Ames Research Center 40- by 80-ft Wind Tunnel. The SHARC configuration represents an advanced low-observable fighter aircraft, and features a clipped diamond wing with leading- and trailing-edge sweep angles of ±40 deg, a chined forebody, leading-edge extensions, and a vee-tail. Data covering the angle of attack range from -4 deg to +42.4 deg, and sideslip angles ranging from - 10 deg to +10 deg were acquired at a dynamic pressure of 40 psf. Test data are presented for symmetric and asymmetric wing jet nozzle blowing. Blowing coefficient values ranged from a minimum of 0.005 to a maximum of 0.020. The results indicate that wing jet nozzle blowing is an effective lift-enhancement device, giving an across-the-board net increase in lift over the entire angle-of-attack range tested. The jets were also found to improve the aircraft's drag polar. Roll control using asymmetric jet blowing equaled or exceeded that availahle via the deflection of only a single aileron