Abstract: As the proportion of structural weight of advanced civil transport aircraft gets smaller and smaller, the aircraft shows higher flexibility, traditional rigid model assumption may lead to large errors in the study of aircraft flight control. Considering the large deformation movement of the wing, strain based nonlinear beam model is used to establish a coupling model of structural dynamics and traditional rigid flight dynamics. The aerodynamic parameters of the rigid-elastic coupling aircraft equivalent to the rigid model are obtained by the equivalent method, and the differences between the traditional rigid model and the rigid-elastic coupling model on aileron and vertical gust response are compared through simulation. The results show that the elasticity of the wing will reduce the aileron efficiency by 18.77% during the roll maneuver. Under the action of vertical gust, the wing root bending moment predicted by the rigid-elastic coupling model is 8.35% lower than that by rigid model, and elastic motion of the wing also has an impact on rigid motion.

Key words: rigid-elastic coupling, nonlinear beam, aerodynamic parameters, flight simulation