Propulsion control of a large civil aircraft using on-line control allocation

This paper explores the possibility of controlling an aircraft using only engine thrust in the event of total control surface failure (due to the loss of hydraulics) using an on-line sliding mode control allocation scheme. Here, both lateral and longitudinal fault tolerant control (FTC) of a non-linear model of a civil aircraft is presented. The simulations have been undertaken using software called FTLAB747. The effectiveness level of the actuators is used by the control allocation scheme to redistribute the control signals to modulate engine thrust when a total hydraulic failure occurs. The simulation results from the non-linear model give good performance and show it is still possible to bring the aircraft to a near landing position without restructuring the controller.