Flap/slat actuation system for an aircraft

Abstract

The problem of providing a flight control panel actuation system, including asymmetry brakes, which will fit into aircraft wings having narrow supercritical air foil shapes, and yet provide a degree of safety with regard to preventing asymmetry which is as good or better than that provided by prior actuation systems is solved by an actuation system which positions an asymmetry brake inboard of an outermost flight control panel actuator within the aircraft wing. The asymmetry brake utilizes a jaw type clutch coupled to an electrical solenoid through a ball spline mechanism to provide significantly greater braking capacity in a given volume than other types of braking devices. The outermost control panel actuator includes an integral no-back to hold that actuator against further movement, should a driveline connection between the asymmetry brake and the actuator be severed. Where the actuation system includes multiple actuators, only one of the actuators is equipped with end of travel stops, therefore allowing the remaining actuators in the system to be physically smaller because they are not required to react loads incident with limiting end of travel. By making the other actuators in the system physically smaller, they are more readily fitted into supercritical wings.