The propulsive-only flight control problem

Attitude control of aircraft using only the throttles is investigated. The long time constants of both the engines and the aircraft dynamics, together with the coupling between longitudinal and lateral aircraft modes, make piloted flight with failed control surfaces hazardous, especially when trying to land. The author documents the results of in-flight operation using simulated failed flight controls and ground simulations of piloted propulsive-only control to touchdown. Augmentation control laws to assist the pilot are described using both optimal control and classical feedback methods. Piloted simulation using augmentation shows that simple and effective augmented control can be achieved in a wide variety of failed configurations