History of the Flight
On 5 June 2021, around 15:30 local time, a Robin DR400-160 registered F-GKQG took off from grass runway 26 at Loudun aerodrome (Vienne, France). The aircraft was operated by Aero Club Rennes Ille-Et-Vilaine and carried a pilot and two passengers. Shortly after becoming airborne, the aircraft deviated to the left. It touched down again off the runway and continued at an angle of about 30° to the runway centerline, crossing the flying club's parking area. The right wing struck the left wing of a parked Robin DR400-120 registered F-GXJR, which was being prepared for start-up by a student pilot and an instructor. The collision rotated the parked aircraft 180 degrees and F-GKQG 90 degrees. The elevator of F-GKQG then struck the hangar door, and the left wing trailing edge hit the self-service refuelling station before the aircraft came to a stop. Both aircraft were destroyed.
Additional Information
Aircraft and Site Examination
The wreckage of F-GKQG came to rest about 50 m laterally from the threshold of runway 08. Run marks began in the grass at a 30° angle to the runway and continued through the signal area. The spacing indicated skidding. The fuselage was severed approximately 50 cm aft of the wing's trailing edge, behind the cabin. The flaps were damaged, and the flap control lever was found locked in the fully extended position. Impact marks on the refuelling station and left flap confirmed full extension at impact. Flight control linkages were continuous, with no pre-impact anomalies except pedal friction attributed to accident damage. Braking tests and nose gear operation were normal.
Pilot Information
The 67-year-old pilot held a Private Pilot Licence (Aeroplanes) issued in 2011, with 246 total flight hours. In 2021, he had made six flights (four hours), including two instructional flights and three in a DR400-120. His last flight in a DR400-160 (F-GKQG) was on 20 July 2020. He was flying to Loudun for the first time.
Meteorological Conditions
Météo-France estimated visibility greater than 10 km, average wind 8 kt from 320° with gusts to 13 kt, scattered cumulus at 5,000 ft, and temperature 21°C.
Aerodrome Information
Loudun is an uncontrolled aerodrome with a single unpaved runway 08/26, 790 m long and 60 m wide. Pilots use the A/A frequency.
Engine Effects
The DR400-160 features a clockwise-rotating propeller. The helical blast creates an asymmetric airflow on the tail fin, inducing a left yaw. At low speed with full flaps, lift increases reduce rotation speed, amplifying the yaw effect and reducing rudder effectiveness. The propeller torque also induces a left roll, which is increased by the left yaw.
Statements
The pilot stated he applied power while braking, and at about 105 km/h, the aircraft began deviating left. He applied right rudder and right stick, but the deviation continued, and he reduced power. He believed he had set flaps to the first detent and did not touch the flap lever afterward. The front-right passenger, also a private pilot, stated that after rotation, the aircraft deviated slowly left and did not respond to right inputs. An onlooker reported seeing the aircraft at about five metres altitude, deviating left with rolling wing movements, before losing sight.
Conclusions
The investigation concluded that during the takeoff, the pilot likely took off with the flaps in the fully extended position without realizing it. Shortly after rotation, the aircraft deviated left, touched down, and struck the parked aircraft and hangar. Contributing factors included failure to check flap position, unexpected take-off due to unintentional full flap extension, insufficient corrective rudder input, and the pilot's lack of recent experience in the DR400-160.