Abstract: An actuator control system for coupling to one or more flight control computers (FCCs); comprising: apparatus for controlling an aerodynamic control surface in response to commands received from one or more FCCs, and, integrated with the controlling apparatus, a failure protection system comprising apparatus arranged to provide at least one of the following functionalities: a servo monitor functionality, a command monitor functionality, and a loop closure functionality. Thus, in the overall flight control system, some or all of the elements of the failure protection system are located in the actuator control stage.

Abstract: An actuator control system for coupling to one or more flight control computers (FCCs); comprising: apparatus for controlling an aerodynamic control surface in response to commands received from one or more FCCs, and, integrated with the controlling apparatus, a failure protection system comprising apparatus arranged to provide at least one of the following functionalities: a servo monitor functionality, a command monitor functionality, and a loop closure functionality. Thus, in the overall flight control system, some or all of the elements of the failure protection system are located in the actuator control stage.