What happened
On June 30, 2012, a Mudry Cap 10B, registration F-GKKZ, departed from Nangis Les Loges aerodrome for a paid passenger flight. During the return portion of the flight, the pilot intended to perform a "peel-off" maneuver, a non-standard aerobatic figure, to avoid interference with another aircraft operating in the aerobatic box.
The pilot approached runway 23 at a high speed of approximately 240 km/ h. At an altitude of 50 ft, the pilot initiated a steep left turn while climbing and reducing power to decrease speed for flap extension. After completing a half-turn at approximately 300 ft, the speed had dropped to 140 km/h, at which point the landing flaps were deployed. The pilot then continued the turn in a descent at roughly 130 km/h to realign with the runway centerline. At an altitude of approximately 150 ft, the aircraft suddenly dropped without any prior warning of a stall. Despite immediate corrective actions, including leveling the wings, applying power, and pushing the nose forward, the aircraft struck the ground with a slight right bank. Both the pilot and the passenger escaped the undamaged aircraft without injury.
The investigation
The investigation focused on the nature of the maneuver and the regulatory framework governing the flight. The "peel-off" maneuver, while practiced by some club members, is classified as aerobatic because it involves intentional changes in attitude and speed. The investigators examined the pilot's experience, noting he was a qualified instructor with 2,600 total flight hours, including 1,100 on type.
Crucially, the investigation looked into the legality of the flight type. Under local regulations, private pilots performing local flights for remuneration are prohibited from conducting aerobatic maneuvers or formation flying. The investigation established that the pilot's decision to perform the maneuver was part of a pre-planned sequence for the end of the flight.
Findings
- The primary cause of the accident was the pilot's decision to perform an aerobatic maneuver that did not provide sufficient altitude to recover in the event of a loss of control.
- The routine practice of this maneuver during local flights led to a dangerous normalization of the risk.
- The pilot failed to adequately account for the wind conditions, specifically a 15-knot crosswind from 200 degrees, which made the descending portion of the maneuver more critical.
- The practice of such maneuvers was also facilitated by the fact that several other club members regularly performed the same maneuver.