Abstract: A drive assembly is operable to move control surfaces on wings of an aircraft. The drive assembly may include a gear reduction assembly which is driven by a pair of motors. The drive assembly has output members which are connected with the control surfaces on the wings of the aircraft. Torque limiting brake assemblies are operable between an engaged condition in which they are effective to prevent rotation of output members and a disengaged condition in which the brake assemblies are ineffective to prevent rotation of the output members. Actuator assemblies are connected with the torque limiting brake assemblies. The actuator assemblies are operable to effect operation of the torque limiting brake assemblies from a disengaged condition to an engaged condition in response to transmission of predetermined torques through the actuator assemblies to the output members.

Abstract: An aircraft flap drive system utilized a variable displacement motor (15) having a fluid pressure actuated device (23) to vary the displacement of the motor. The system includes a displacement control valve (41), and an electrohydraulic control means (55,67,85) operable in response to an electrical input signal (91) to communicate pressurized fluid from a source (11) to the motor. The displacement control valve (41) includes a load sensing arrangement (13,53,49) responsive to an increasing load on the motor to bias the displacement control valve toward a position whereby the motor moves toward its maximum displacement (minimum flow). One result is that the conventional fixed displacement motor, of a particular size and weight, may be replaced by a variable motor which is smaller and lighter.