What happened
On the morning of 18 August 2024, a Cessna 150F with registration ZS-EGZ was parked on the grass near a hangar at Margate Airport (FAMG) in KwaZulu-Natal. The aircraft had arrived from Virginia Airport earlier that morning for a private flight under visual meteorological conditions.
Following a period of refueling, the pilot attempted to start the engine. After several unsuccessful attempts, the pilot performed a hot start procedure. During this third attempt, smoke was observed emerging from the engine cowlings. The pilot immediately evacuated the aircraft to summon the airport's fire department. By the time the firefighting team arrived, the aircraft had caught fire. While the fire was eventually extinguished, the engine section sustained substantial damage.
The investigation
SACAA AIID examined the circumstances surrounding the engine failure and subsequent fire. The investigation confirmed that the pilot held a valid Private Pilot Licence and was properly rated for the aircraft type. The aircraft's maintenance records showed it was within its period of airworthiness, with the most recent periodic inspection completed in November 2023.
Investigators focused on the engine starting sequence and the pilot's adherence to the Pilot Operating Handbook (POH). The investigation noted that while a portable fire extinguisher was available on board, it was not utilized by the pilot during the incident.
Findings
- The engine had been flooded with excess fuel during the priming process.
- The pilot failed to follow the POH-recommended procedure for clearing a flooded engine, which involves setting the mixture to full lean and opening the throttle to clear the combustion chambers.
- The ignition of the fire was caused by excess fuel coming into contact with the hot sections of the engine during the hot start attempt.
- The severity of the damage was increased because the on-board fire extinguisher was not deployed.
Safety action
To prevent similar occurrences, the following safety measures are recommended for flight operators and training organizations:
- Pilots should be trained to strictly follow POH procedures for engine recovery, specifically regarding mixture and throttle adjustments during over-priming.
- Training should emphasize the immediate use of on-board fire extinguishers during an engine fire, even when external fire services are being summoned.
- Flight operators should conduct recurrent training on handling engine flooding and emergency response measures.