Patent ID: 7891180

Claim:
A method of monitoring movement of a plurality of actuators, each acting on a flight control of an aircraft, which is implemented by a monitoring device applied on the aircraft, wherein the flight control is assisted power-wise by a hydraulic circuit and the hydraulic circuit being able to deliver a hydraulic failure indication, a displacement servo-control for each actuator is generated from a respective actuator position indication and a respective position set-point indication computed by a computation unit, wherein an alarm phase is initiated on detection of the presence of a servo-control operating servo-control operating error, the alarm phase is initiated at a time t 0 and being kept open as long as the error is present, wherein the alarm phase comprises the following steps: determining whether at least one actuator is in a blocked state or in a divergent state, when the at least one actuator is in the blocked state, determining whether the duration of the alarm phase exceeds a value T conf2 ; when the at least one actuator is in the divergent state, determining whether the duration of the alarm phase exceeds a value T conf1 ; and when the at least one actuator is in the blocked state, if the duration of the alarm phase does not exceed a value T conf2 , determining whether the hydraulic circuit has delivered the hydraulic failure indication, wherein at a time t n , where n is greater than or equal to 1, (i) if the at least one actuator is in the blocked state and the duration of the alarm phase exceeds the value T conf2 , or if the at least one actuator is in the divergent state and the duration of the alarm phase exceeds the value T conf1 , the generation of all the displacement servo-controls, produced by the computation unit and intended for the actuators acting on the flight controls, is disabled and the alarm phase is closed, or (ii) if the at least one actuator is in the blocked state, the duration of the alarm phase does not exceed the value T conf2 , and a hydraulic failure indication is received, the generation of the displacement servo-control, produced by the computation unit and intended for the at least one actuator, is disabled and the alarm phase is closed.