A fly-by-wire (FBW)
system comprising a plurality of
servo actuators for controlling the
flight control surfaces of an aircraft in which each of the
servo actuators may comprise a flight control computer (FCC) that controls the output of the
servo actuator. Input from a
pilot or
autopilot system may be communicated directly to the
servo actuator FCCs, which may perform the requisite computations to determine the
servo actuator output. For each axis, a primary and a secondary
servo actuator may be provided, and the secondary servo
actuator may operate in the event of a failure in the primary servo
actuator. Each servo actuator may have two motors, each configured to drive an end of a differential such that each motor can act as a
brake, a
clutch or motor on the servo actuator.