Primary finding
Probable cause
The elevator control restriction was caused by the failure of an elevator autopilot servo control cable which failed due to cyclic fatigue. The slack in the cable wrapped around the servo mount in such a way that it interfered with the rotation of the servo mount. The servo mount remained connected to the aft side of the elevator control quadrant by the intact aft cables. This condition resulted in the limited rotation of the elevator control quadrant in one direction.