What happened
On September 12, 2010, at approximately 15:55, a SOCATA MS 893 A Rallye Commodore, registration F-BSKC, was performing glider towing operations at the Condom aerodrome. Following the fifth tow of the afternoon, the pilot performed a low-altitude pass over runway 11 to release the tow cable near the threshold of runway 29, a standard procedure to prepare for the next glider's departure.
During the initial climb following the release, the engine suddenly lost power. Due to the low altitude, the pilot was unable to return to runway 29 and instead executed an emergency landing in a nearby sunflower field. The aircraft struck the ground at a low horizontal speed and came to a halt within a few meters. The impact caused heavy damage to the airframe, specifically bending the nose and main landing gear. The pilot, who was the sole occupant, escaped the aircraft without injury.
The investigation
The investigation focused on the sudden loss of engine power and the mechanical state of the aircraft. Investigators noted that the propeller was not rotating at the time of impact, suggesting the engine was not producing power during the descent. Post-accident inspections of the Lycoming O-360-A3A engine revealed that the fuel system was functional, with both the left and right tanks containing 25 and 21 liters of fuel, respectively, and no air in the fuel lines was found to explain the power loss.
Upon inspection of the cockpit, the tow cable release mechanism was found to be functioning correctly, and the cable remained attached to the aircraft. While the pilot could not definitively recall if the mixture control had been moved, the investigation focused on the physical layout of the controls. The investigation also noted that the electric fuel pump had been left running from the start of the descent until after the aircraft had come to a stop.
Findings
- The primary cause of the engine failure was pilot error involving the misuse of a cockpit control.
- The pilot recalled manipulating a control at the exact moment the cable was released and initially believed they had mistakenly selected the wrong fuel tank.
- Although the mixture control and the cable release lever are different in both shape and color and are separated by approximately 30 centimeters, the pilot's action led to the immediate loss of engine power.