What happened
On May 25, 2002, a Cessna 172 RG 'Cutlass', registration F-GEBT, was performing the final leg of a charity-organized flight tour of France. The flight, which included a cameraman as a passenger, was traveling from Avignon toward Orange-Caritat. After approximately two hours and 15 minutes of flight at an altitude of roughly 900 feet, the pilot was established on the long final approach for runway 33 at Orange-Caritat aerodrome.
While in radio contact with the control tower, the engine ceased operation. The pilot notified the controller of the engine failure and declared his intention to perform an emergency landing in a field. While attempting to maneuver away from vineyards to find a suitable landing site, the engine briefly restarted before failing permanently. The pilot identified a short wheat field and attempted to land with the landing gear retracted, deploying a single flap notch. The aircraft touched down and came to a stop approximately 25 meters from the point of impact. The accident resulted in injured occupants and the destruction of the aircraft.
The investigation
The investigation focused on the fuel state and the pilot's navigation and planning procedures. Examination of the wreckage revealed that the left fuel tank was empty, while only a small amount of fuel remained in the right tank.
Discrepancies were found regarding fuel endurance calculations. For the event's documentation, the pilot had stated a maximum endurance of six hours. However, the aircraft had been flying for two hours and 45 minutes since its last refueling. The investigation found that club documentation provided to pilots suggested a usable fuel capacity of 236 liters and a consumption rate of 42 liters per hour, implying a safe endurance of 5 hours 15 minutes. Conversely, a placard on the aircraft's dashboard indicated a consumption rate of 43 liters per hour.
Furthermore, the investigation established that the pilot had not attended the daily briefing and was unaware of the specific weather conditions for the route. Due to a malfunctioning heading indicator, the pilot relied solely on GPS for navigation. Additionally, the aircraft's logbook did not fully record all refueling events performed during the tour.
Findings
- The primary cause of the engine failure was fuel exhaustion, driven by the pilot's erroneous understanding of the aircraft's performance characteristics.
- The pilot failed to monitor fuel gauges during the flight and left the fuel selector on the 'BOTH' position, which led to the depletion of the left tank while the right tank still contained usable fuel.
- Increased fuel consumption was likely exacerbated by the effects of the Mistral wind and frequent altitude changes requested to assist the cameraman with filming.
- Inaccurate fuel endurance planning contributed to the depletion of the fuel supply before reaching the destination.