What happened
On June 10, 2003, a SOCATA MS 893 A Rallye Commodore, registered F-BTJV, was returning to the Niort aerodrome following a 50-minute local flight. While cruising at approximately 2,300 feet and preparing to enter the traffic pattern for runway 2slot 25, the pilot noticed the engine RPM dropping to 1,500. After briefly switching the fuel selector to the left tank, the RPM dropped further to 1,200. As the pilot attempted to fly the approach, the engine stopped completely. At an altitude of roughly 300 feet, the pilot determined that the runway could not be reached and opted for an emergency landing in a field near the threshold of runway 25. The aircraft struck the ground heavily, causing the nose gear to collapse before the aircraft came to a halt.
The investigation
The investigation focused on the fuel state and the pilot's management of the fuel system. Post-accident analysis revealed that the right fuel tank was empty, while the left tank contained approximately 50 liters of fuel. At the time of the incident, the fuel selector was set to the right tank. The pilot reported that the right tank had initially contained about 40 liters and the left tank about 60 liters before departure. While the pilot had used the left tank for the first ten minutes of the flight, the right tank had been in use during the subsequent maneuvering phase.
Findings
- The engine failure was caused by fuel exhaustion in the active tank.
- The pilot relied on an incorrect fuel consumption estimate of 25 liters per hour, a figure provided to him during training for a different aircraft type (DR 400).
- The manufacturer's manual specifies a much higher consumption rate for the SOCATA MS 893 A, ranging between 30 and 47 liters per hour depending on operating conditions.
- The pilot's insufficient knowledge of the aircraft's performance characteristics led to the miscalculation of remaining endurance.
- The accident resulted in one injury to the pilot and substantial damage to the aircraft.