Numerical analyses of discrete gust response for a flexible aircraft

Based on Navier-Stokes equations and structural and flight dynamic equations of motion, dynamic responses in vertical discrete gust flow perturbation are investigated for a supersonic transport model. A tightly coupled method was developed by the subiteration between aerodynamic equations and dynamic equations of motion. First, under the assumption of rigid-body and single freedom of motion in the vertical plunging, the results of direct-coupling method are compared with the results of quasi-steady model method. Then gust responses for the one-minus-cosine gust profile are analyzed with two freedoms of motion in plunging and pitching for the rigid and flexible airplane configurations.