What happened
On July 3, 2004, at approximately 19:15, a Robin DR 400-180, registration F-GDKY, was performing a local flight departing from Coulommiers airfield. The pilot began the flight at 18:30 with the fuel selector set to the left tank. After 45 minutes of flight, the aircraft was established on a right-hand downwind for runway 27 at 700 feet.
During the final approach, at an altitude of approximately 500 feet, the pilot noticed a drop in engine RPM. In an attempt to restore power, the pilot activated the carburetor heat and the electric fuel pump, while also cycling the fuel selector between the center and right tanks. These actions failed to resolve the issue. Realizing the aircraft could not reach the airfield, the pilot opted for a forced landing in a nearby wheat field to avoid a grove of trees. The aircraft struck the ground with a high vertical velocity, causing the engine to separate from the airframe at the firewall, resulting in the destruction of the aircraft.
The investigation
Investigators examined the wreckage and found that while the right and center tanks contained fuel, the left tank was empty. The electric fuel pump switch was in the "on" position. Analysis of the aircraft's logbook indicated an average fuel consumption of 32 liters per hour. At the time of departure, approximately 134 liters of usable fuel should have been available, as the pilot had added 50 liters to the center tank prior to takeoff.
The investigation focused on the pilot's fuel management procedures. It was determined that the pilot had failed to monitor the fuel selector, operating under the mistaken belief that the center tank was selected and that no further fuel management was required during the flight. The pilot's previous experience was primarily on aircraft types, such as the Robin DR 400-120 and Cessna 150, which do not require manual fuel selector adjustments during flight.