History
On 6 March 2024, at Nantes-Atlantique airport, a pilot and passenger arrived at the flying club for a local flight in a Robin DR400-160, registered F-GYAC. The pilot removed the aircraft from the hangar and positioned it at the refuelling point. The passenger boarded. After the pre-flight inspection, the pilot performed the cold start procedure. Pressing the starter button caused the propeller to move slightly but the engine did not start; a friction noise was heard. This was repeated three times without success. The pilot then turned the battery switch to OFF and rotated the magneto selector key to a position he believed was OFF, but did not remove the key. He operated the parking brake lever and exited the aircraft to rotate the propeller manually.
As the pilot rotated the propeller and passed the compression point, the engine suddenly started. The pilot quickly moved away and saw the aircraft begin to move forward. He attempted to stop it by pushing on the left wing, causing the aircraft to spin left. He climbed onto the left wing and tried to enter the cabin. The aircraft gained speed and ran on the grass strip toward a parked A320 in the commercial parking area. The pilot tried to reach the cabin again but was prevented by the aircraft's movement. He partially entered the cockpit and, by bending over, pressed the right rudder pedal with his hand to turn the aircraft right. He eventually entered and regained control, returning the aircraft to the club.
Pilot Information
The 55-year-old pilot held a Private Pilot Licence (Aeroplanes) since 25 January 2016, with about 200 total flight hours, including 3 hours and 40 minutes on type in the previous three months. He regularly flew F-GYAC.
Aircraft Information
The Robin DR400-160 is equipped with a 160 hp Lycoming engine. The day before the event, maintenance was performed on the electrical system of the anti-collision lights, lasting about 20 minutes. After the maintenance, the battery voltage was 11.6 V. Following the incident, no anomalies were found; the battery voltage measured 8 V, likely due to the four start attempts. The magneto selector has four positions: OFF (both magnetos grounded), R (left grounded), L (right grounded), BOTH (neither grounded). The parking brake system is operated by pressing and holding brake pedals, pulling the brake handle, and releasing the pedals. The brake is released by pushing the lever back.
Conclusions
The repeated use of the starter without engine start caused a sharp drop in battery voltage, making normal starting uncertain. The pilot decided to exit the aircraft without an appropriate checklist. Before exiting, he did not fully apply the parking brake, did not remove the magneto key, and left the throttle not at idle and the mixture at full rich. When the propeller was rotated manually, the engine started and the aircraft moved forward. The pilot managed to eventually regain control, avoiding a collision with the A320.
Contributing factors include the non-application of the engine shut-down checklist, which contributed to the unexpected engine start and ground run without a pilot at the controls.