What happened
On June 6, 2001, a Grob G115, registration F-GGOJ, was performing a local flight from Rennes aerodrome. Shortly after takeoff from runway 28, the pilot experienced engine sputtering and attempted to perform a right-hand turn at a low altitude. During this maneuver, the aircraft lost control and crashed approximately 300 meters from the threshold of runway 10, where it subsequently caught fire. The impact was severe, and the forward section of the aircraft was destroyed by the fire. The accident resulted in one fatality and one serious injury.
The investigation
Investigators examined the aircraft's fuel system and the pilot's pre-flight procedures. The Grob G115 is equipped with a single 100-liter tank controlled by a fuel selector. Testing on an identical aircraft demonstrated that if the selector is positioned such that the "F" (closed) indicator is visible in both windows, the fuel pressure drops to zero within approximately two and a half minutes when the electric pump is turned off.
Upon inspecting the wreckage, investigators found the fuel selector in a position indicating the valve was closed. The investigation also noted that the aircraft had recently undergone a 50-hour inspection, during which the fuel valve would have been manipulated. Furthermore, the pilot had performed pre-flight checks from memory rather than using a written checklist, a practice influenced by the habit of leaving the valve in the open position.
Findings
- The primary cause of the engine failure was a lack of fuel supply due to the fuel valve being left in the closed position.
- The pilot failed to verify the actual position of the fuel selector during the pre-flight inspection, relying instead on memory and the assumption that the valve was open.
- The decision to attempt a turn at a low altitude following the engine failure contributed to the loss of control.
- The pilot utilized only a portion of the available runway length for takeoff, which limited available options for managing the emergency.
- Routine errors and a lack of checklist discipline were identified as contributing factors.