What happened
On 31 March 2025, a Vans RV-8 aircraft, registration ZU-IRG, was performing a private flight from Grand Central Aerodrome in Gauteng toward Potchefstroom Aerodrome in the North West province. The flight was being conducted under visual meteorological conditions.
While cruising at approximately 6,500 feet over a farming region near Fochville, the pilot detected the smell of fuel emanating from the engine compartment. Shortly after this observation, the engine lost power. The pilot attempted several troubleshooting measures, including switching fuel tanks and cycling the fuel pumps and engine control unit, but the engine failed to recover. Due to the diminishing altitude, the pilot executed a forced landing on a grass area adjacent to Church Street, near a public road. During the landing roll, the main wheels sank into the soft ground, causing the aircraft to nose over. The aircraft sustained substantial damage, though the pilot escaped without injury.
The investigation
SACAA AIID examined the aircraft following its recovery to Potchefstroom Aerodrome. The investigation focused on the fuel system, which utilizes four injectors and a pressure regulator to maintain delivery to the cylinders. Investigators inspected the engine components and compared the condition of the injector bodies.
Findings
- The investigation established that the injector fitting on cylinder number 1 had become loose, leaving visible threads on the injector body.
- This loose fitting caused the fuel line to depressurize, which prevented sufficient pressure from being maintained through the injectors.
- Because the injectors are connected in series, this specific failure led to a significant reduction in engine power.
- The aircraft was airworthy at the time of departure, and a 50-hour inspection had been completed recently on 28 March 2025.