What happened
On 17 January 2009, a Beechcraft Baron 58, registered A2-AHF, departed from a private farm near Thabazimbi, Limpopo, destined for Wonderboom Aerodrome. During the initial climb, the pilot and five passengers heard a loud, rhythmic banging noise originating from the right side of the aircraft. Although engine instruments appeared normal, the pilot performed standard shutdown procedures for the right-hand engine to investigate the perceived issue.
After leveling off at approximately 5,000 feet, the pilot attempted to restart the engine. However, the aircraft began to lose airspeed and altitude rapidly, developing a significant rightward yaw. Unable to maintain control, the aircraft descended into trees and impacted the ground. Despite the destruction of the aircraft, all six people on board survived the impact without injury.
The investigation
An investigation by the SACAA AIID established that the aircraft was properly maintained, with its last annual inspection completed in June 2008. While the aircraft was registered in Botswana, investigators were able to access maintenance records in South Africa.
Physical evidence at the wreckage site showed that the number one engine was operating at full power at the moment of impact, while the number two engine throttle was in the off position. The investigation also revealed that the co-pilot's seatbelt and buckle had been left hanging outside the aircraft during the flight. This loose component was identified as the actual source of the loud banging noise heard during the climb.
Findings
- The primary cause of the accident was the pilot's decision to shut down the number two engine at a low altitude shortly after takeoff.
- The pilot's actions led to a rapid loss of altitude and directional control.
- The loud noise heard by the crew was caused by the co-pilot's seatbelt and buckle flapping outside the cabin.
- The pilot demonstrated poor airmanship by reacting to an unverified noise by disabling an engine during a critical phase of flight.