Flight Details
The private pilot, accompanied by his wife and two daughters, was flying from Port Elizabeth to his farm in the Cradock district. Upon arrival at Cradock, the pilot overflew the runway for inspection before entering the downwind leg.
In-Flight Event
While on the downwind leg, the aircraft began to roll and yaw to the left. All engine indications were reported as normal. The pilot decreased power on the right-hand engine to maintain control. With the reduction in power, the pilot was unable to maintain altitude.
Forced Landing and Damage
The pilot executed a forced landing on an open field. The aircraft sustained extensive damage during the landing. No injuries occurred.
Investigation Findings
An on-site investigation was conducted on 24 December 2000, after which the aircraft was recovered to Lanseria aerodrome for further inspection. Inspection of the left-hand propeller revealed that the carbon block of the low pitch proximity sensor, which normally runs inside the low-pitch stop collar, was bent down at an angle. This condition would have rendered the secondary low-pitch stop inoperative. Due to damage sustained to the aircraft's electronic circuitry during the accident, it was not possible to verify the proper operation of the propeller pitch control system.
Probable Cause
The official probable cause, as stated by the investigation, is that due to damage sustained during the accident, the proper operation of the propeller pitch control system could not be verified, and therefore the cause of the accident remains undetermined.