No abstract

No 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 T\mnel. 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 available via the deflection of only a single aileron. Nomenclature C D = drag coefficient, stability axis C L -lift coefficient, stability axis C Lmax = maximum lift coefficient C, = rolling moment, body axis C n = yaw moment, body axis C^ = blowing coefficient c = wing mean aerodynamic chord LID = lift-to-drag ratio L/D max = maximum lift-to-drag ratio V = tunnel freestream velocity, ft/s a = angle of attack, deg /3 = angle of sideslip, deg A = delta or incremental AC L /C M = augmentation ratio 8 = control surface deflection angle, deg A*, = jet nozzle orientation angle, deg 4> = jet nozzle inclination angle, deg

No abstract

No abstract