What happened
On 29 May 2008, a Piper PA23-250 Aztec, registration ZS-DTK, was performing a private ferry flight from Wonderboom Aerodrome (FAWB) to Springs Aerodrome (FASI). Shortly after rotating for takeoff on runway 29, the aircraft experienced a sudden loss of power. The pilot reported that the right engine failed first, causing the aircraft to yaw heavily to the right. In an attempt to maintain directional control, the pilot applied left rudder; however, the aircraft could not be stabilized and lost altitude. The pilot subsequently shut down the left engine, and the aircraft impacted the ground on the right side of the runway, resulting in substantial damage to the airframe. The pilot sustained minor injuries.
The investigation
SACAA AIID investigators examined the wreckage and the mechanical components of both engines. While the pilot initially believed a mechanical failure occurred on the right side, bench testing of the engines, magnetos, and fuel pumps revealed no mechanical defects. The investigation focused on the fuel system, noting that the fuel selectors were set to the outboard tanks, which were found to be empty. Furthermore, the investigation identified that the aircraft's Certificate of Airworthiness had been cancelled due to a lack of maintenance records, and no maintenance documentation existed for the aircraft for over six years. Additionally, the investigation found that the flaps were in the landing position during takeoff, contrary to the manufacturer's handbook recommendations.
Findings
- The primary cause of the accident was fuel starvation, as both engines lost power nearly simultaneously because the selected outboard tanks were empty.
- The pilot lacked the necessary type rating for the Piper PA23-250 Aztec and had no documented experience on this specific aircraft type.
- The aircraft was operating without a valid certificate of airworthiness and lacked up-to-date maintenance records.
- The pilot's lack of familiarity with the aircraft's fuel system likely contributed to the incorrect selection of fuel tanks.
- The use of flaps in the down position during takeoff may have increased drag and hindered the aircraft's ability to gain necessary airspeed.