AP Hydraulic Blocks
When the automatic pilot and stabilization function is selected by the pilot, movement control is ensured by the AP hydraulic unit.
This unit is installed together with the flight control linkage. The AP Block is supplied with hydraulic pressure by a hydraulic power unit. When supplied with pressure, the hydraulic unit provides the control loads required to operate the flight controls. Helicopter autopilot systems usually use three or sometimes four axes to provide stability.