Roll-yaw control at high angle of attack by forebody tangential blowing

The feasibility of using forebody tangential blowing as the only actuator to control the roll-yaw motion of a wind-tunnel model at high angles of attack is demonstrated experimentally, To accomplish this, a unique model is developed that describes the unsteady aerodynamic moments generated by both vehicle motion and the applied blowing. This model is sufficiently detailed to predict the transient motion of the wind-tunnel model, but is simple enough to be suitable for control design and implementation. Successful closed-loop control is demonstrated experimentally for a delta wing body model incorporating a 70-deg sweep angle and a cone-cylinder fuselage, Experiments were performed at 45-deg nominal angle of attack. At this condition, the natural motion of the system is divergent.