Aircraft flight management with actuator major failure

This communication considers the case of total loss of hydraulic power by a transportation aircraft. The aim of this study is to propose control solutions to the design of new guidance function for the flight director system, or an emergency mode for the auto-throttle to control the thrust of a multi-engine transportation aircraft to make it return safely near ground level with acceptable landing conditions. The approach is based on a model of the flight dynamics involving all its major nonlinearities and couplings. Since after this major failure the aircraft is no more fully controllable, non linear inverse control technique is used to design control laws allowing the realization of a sequence of basic manoeuvres sufficient to turn achievable emergency landing. Some simulation results are displayed.