History of the Flight
On 16 June 2019, a Robin DR400-140B, registered F-GBIA, operated by Aéroclub de Boulogne Billancourt, was returning from Deauville Normandy aerodrome to Saint Cyr l'École aerodrome with a pilot and one passenger on board. Around 20:00 local time, while on the downwind leg for runway 29 at an altitude of 700 feet, the pilot reported engine problems to the control tower. The engine had stopped and restarted briefly before stopping completely. The pilot performed a forced landing in a wheat field. During the landing roll, the aircraft struck a green fence obscured by vegetation, causing the nose gear to fail. The aircraft came to rest a few metres beyond the fence. The pilot secured the aircraft and evacuated with the passenger.
Pilot Information
The 56-year-old pilot held a Private Pilot Licence (PPL) and had logged 255 flight hours, including about 4 hours 30 minutes in the preceding 90 days, all on the accident aircraft.
Weather Conditions
Météo-France reported wind from 240° at 6 to 7 knots, visibility greater than 10 km, no clouds, and an air temperature of 21°C.
Examination of the Aircraft
The wreckage was examined; the main fuel tank (capacity 110 litres) contained about 50 litres of fuel. The range extension fuel tank (capacity 50 litres) was empty. The fuel transfer lever was found in the 'pushed in' (not activated) position. All fuel system components were operational, with no leaks or contamination detected. The engine was tested on a test bench and performed nominally; no faults were found in the carburettor, mechanical pump, or electric pump. The fuel transfer valve worked correctly, and it took five minutes to transfer 10 litres from the range extension tank to the main tank during a test.
Fuel Consumption Analysis
Based on the pilot's statement, the pre-flight fuel estimate was about 55 litres in the main tank and about 37 litres in the range extension tank. Engine running time from start-up at Deauville to shutdown was approximately 82 minutes. At an average consumption of about 30 litres per hour, approximately 41 litres of fuel were consumed. Without fuel transfer, only about 10 litres would have remained in the main tank—the minimum for guaranteed engine power in level flight. The total fuel found on board (50 litres) matched the estimated pre-flight quantity, but all fuel was in the main tank, indicating that the fuel transfer system had been activated at some point.
Conclusion
The investigation did not identify any mechanical failure in the fuel system or engine. The manner of engine stoppage was consistent with fuel system unpriming, possibly due to insufficient fuel in the main tank if no transfer from the range extension tank occurred before the first engine misfires.