An Advanced Physics Based Model for Aircraft Upset Real Time Simulation

Flight operations of military aircraft, including those derived from commercial transports, are subject to highly dynamic conditions over broad operational envelopes, which may be further complicated by off-design configurations caused by ballistic damage. Flight simulation, including training applications, must model the aircraft flight dynamics with high fidelity over this operational envelope, requiring extensive aerodynamic databases in current simulation approaches. A physics-based approach for flight dynamics modeling in the high angle of attack and sideslip range is proposed based on a nonlinear lifting line/ surface methodology combined with an unsteady aircraft wake model. This modeling approach has its roots in the aerodynamic modeling of rotorcraft, where dynamic stall and yawed flow conditions are routinely found, and has been recently examined for fixed-wing aircraft in post-stall (upset) conditions. The proposed approach permits real-time simulation of unsteady aerodynamic and wake phenomena. In Phase I, the nonlinear lifting line/surface and unsteady wake model will be applied to high angle aerodynamics and flight dynamics of commercial-derivative military aircraft for demonstration of an advanced aircraft upset simulation, including modeling of ballistic damage effects. This work will form the basis for development of a prototype simulation capability with reduced aerodynamic data requirements for military and commercial applications.