What happened
On March 29, 2003, a Mini Coupe, registration ZS-WMK, was conducting a local flight from Fisantekraal to build flight hours for the pilot's commercial license. While cruising at approximately 2,000 feet AGL, the aircraft's engine failed. The pilot attempted to execute a forced landing by selecting an abandoned dirt road located roughly 15 nautical miles southeast of Malmesbury. However, the presence of high-tension wires spanning the road forced the pilot to land further down the path than originally intended. During the landing sequence, the left wing struck a water channel wall, causing the aircraft to veer left and eventually overturn.
The investigation
The investigation examined the mechanical state of the aircraft and the circumstances surrounding the engine failure. It was noted that the pilot held a valid private pilot license and had 121 total flying hours, with 30 hours on this specific type. The aircraft had been operated for only 32.6 hours since its last annual inspection. The weather at the time of the incident was reported as fine with no wind.
Findings
Technical analysis and pilot testimony identified that the engine failure was triggered by a screw migrating loose on the mechanical fuel pump. This movement caused the pump to lose its prime by sucking in air, leading to the loss of engine power. The pilot noted that the failure could likely have been prevented if the screws on the pump had been properly wire-locked.