What happened
On 21 August 2007, a Mooney M20F, registration ZS-EUF, departed Kimberley Aerodrome for a series of test circuits. Shortly after takeoff, while climbing to approximately 800 ft AGL, the engine began to sputter and subsequently ceased operation. The pilot, the sole occupant of the aircraft, attempted to restart the engine by activating the boost pump and switching to the opposite fuel tank, adjusting the mixture settings; however, these efforts were unsuccessful.
Following the engine failure, the pilot issued a distress call to Kimberley ATC and executed a forced landing in an open field. The aircraft landed on its belly with the undercarriage retracted. During the maneuver, the left wingtip struck a tree, resulting in extensive damage to the fuselage, propeller, engine, and wing. The pilot escaped the accident without injury.
The investigation
SACCA AIID investigators examined the aircraft's maintenance history and the circumstances leading to the fuel exhaustion. The investigation established that the aircraft had been refueled to its 64-gallon capacity on 18 August 2007, but no additional fuel had been added during a subsequent flight to Plettenberg Bay and the return leg to Kimberley.
During the pre-flight inspection, the pilot relied on the sound of fuel "sloshing" and cockpit gauges indicating roughly one-quarter fuel remaining to estimate levels. Post-accident analysis of the fuel tanks revealed that while the left tank contained approximately 15 liters of fuel, the right tank held only 1 liter. The engine was subsequently recovered and tested on a bench, where it was found to be in satisfactory working order.
Findings
- The engine failure was the result of fuel starvation caused by fuel mismanagement.
- The pilot selected the right-hand fuel tank for takeoff, which happened to be the tank with the nearly depleted fuel supply.
- The pilot did not utilize a reliable method to verify the actual quantity of fuel remaining in the tanks prior to departure.
- The aircraft was properly maintained, and the pilot held a valid license and medical certificate.