What happened
On March 17, 2015, a Mudry Cap 10 C, registration F-GYDC, was performing a takeoff roll on runway 21 at the Bordeaux-Léognatic-Saucats airfield. As the pilot applied power and released the brakes, the aircraft began its takeoff roll. At the moment the tailwheel left the ground, the aircraft experienced a sudden leftward veer.
Despite the pilot's attempts to correct the yaw, the aircraft exited the paved runway surface. The main landing gear became bogged in the saturated ground, causing the aircraft to lose stability and capsize onto its back. The pilot noted that engine power was not immediately reduced following the excursion. The aircraft sustained damage during the event, but no injuries were reported.
The investigation
The investigation focused on the aircraft's handling characteristics during the takeoff roll and the environmental conditions. Investigators reviewed meteorological data, which indicated a wind from the east at approximately 10 knots, as observed via the windsock. The investigation also considered the pilot's experience, noting the pilot held a private pilot license with approximately 800 total flight hours, including 130 hours on this specific type.
Findings
- The primary cause of the excursion was a sudden leftward yaw occurring as the aircraft transitioned to a two-point stance.
- The runway environment was affected by wet ground, which contributed to the main gear becoming bogged once the aircraft left the pavement.
- The investigation highlighted the inherent difficulty in controlling tailwheel (classic gear) aircraft, where friction forces acting on the main gear relative to the center of gravity can exacerbate yawing movements during the takeoff roll.