Abstract:A backstepping adaptive sliding mode control method is proposed for STT aircraft attitude tracking control with large deviation, external disturbance and model uncertainty. The attitude dynamic model of STT aircraft is established and linearized, and a three-channel decoupling attitude mathematical model oriented to control is obtained. The controller is divided into an outer loop overload controller and an inner loop angular velocity controller, and double loop controllers are designed based on sliding mode control theory. At the same time, adaptive law is designed to compensate for the disturbance, so that the attitude control system has good adaptability and robustness. The stability of the designed controller is proved by the Lyapunov stability theorem. The numerical simulation results show that the overload tracking error is less than 0.1, the angular velocity tracking error is less than 0.5（°）/s, and there is no full deflection and chattering of the aerodynamic rudder. The effectiveness and feasibility of the designed controller are verified by the numerical simulation results.