Abstract: In a thrust vector control system of the type in which a solid-propellant s generator powers a turbine-driven pump for driving hydraulic actuators for controlling the direction of thrust, the improvement being a feed back control system in which a variable-area gas valve is disposed inline between the gas generator and the turbine. The turbine speed is fed back to an electronic controller where it is compared with a commanded turbine speed. The controller applies forward-loop compensation to provide a signal that adjusts the area of the gas valve to control the operating pressure of the gas generator to drive the turbine speed to the commanded value.