Real-Time, In-Flight Determination of Unsteady Aerodynamic Loads & Moments

A revolutionary approach is proposed to obtain in real time, aerodynamic loads and moments in terms of the instantaneous locations of principal aerodynamic flow phenomena such as the stagnation, flow separation, reattachment, boundary-layer transition, etc. The stability, control, safety, ride quality, and performance of flight vehicles depends upon the instantaneous values of aerodynamic loads and moments, as well as on their derivatives. In recent years successful attempts have been made to introduce flow separation or vortex breakdown point as an inner variable in the state-space representation to mathematically model unsteady aerodynamic loads and moments. Tao Systems has developed techniques to obtain these aerodynamic flow phenomena in real time using hot-film sensors, constant voltage anemometer system, and associated flow diagnostics software. However, there are no techniques currently available to directly obtain aerodynamic loads and moments in terms of these inner variables. The proposed innovation will provide direct input in terms of aerodynamic flow features for the determination of loads and moments, as well as the dynamic stability and control derivatives for flight vehicles under real time flight conditions.