A. System FunctionThe flap actuation system uses the hydraulic system pressure to operate the flaps. The system also locks the flaps when they get to the set position.
B. System ComponentsThe primary components (Ref. Fig. 1 thru Fig. 8) of the system are:
- The Hydraulic Control Unit (HCU)
- Two hydraulic actuators
- The flap isolation valve
- The torque tube
- The flap control surface (Ref. 57-50-00)
C. System OperationThe HCU controls the direction of flow of the hydraulic fluid to operate the hydraulic actuators. The flap isolation valve stops a loss of auxiliary system fluid if a leak occurs in the flap system. The flap torque tube prevents a flap asymmetry condition during correct operation of the system.