ICNPAA 2010: Mathematical Problems in
Engineering, Aerospace and Sciences

In this paper flight simulation of aeroelastic aircraft in landing phase is presented. Hybrid state equations of motion in terms of quasi-coordinates provide the framework for nonlinear simulation. The wings of the aircraft are assumed to be flexible and modeled as cantilever beams undergoing elastic bending and torsion about their elastic axis. Unsteady aeroelastic forces are computed using strip theory and finite state induced flow theory. An asymmetric landing condition in which the elastic aircraft encounters cross wind all the way to touchdown is considered. In order to design the landing controller, nonlinearly coupled equations of motion are linearized about trim condition and separated to two sets of decoupled equations in which the elastic variables affect lateral-directional equations. An optimal-integral-feedforward control scheme is exploited to realize the auto-landing while suppressing wind effects on flight path as well as elastic variables. The performance of the control system is examined through nonlinear simulation.