ICNPAA 2010: Mathematical Problems in
Engineering, Aerospace and Sciences

Modern aircraft designs are continuously driven towards a light weight configuration due to performance and mission requirements. Consequently, these aircraft are characterised with high structural displacements resulting in a reduction of the frequency margin between rigid-body and flexible modes. Strong dynamic coupling may occur in the presence of nonlinearities and in such cases, classical analysis methods are unable to accurately identify the resulting nonlinear behaviour. In this paper, we demonstrate the effect of dynamic coupling between rigid-body, flexible and controller modes on the stability and control of flexible aircraft using a novel analysis approach based on the use of bifurcation analysis linked to classical methods. The robustness of different control law design is also demonstrated.