What happened
On 12 May 2023, a Shark microlight, registration 44BDO, was conducting a cross-country flight from Avignon-Caumont toward La Baule-Escoublac. The flight began following a group excursion from Corsica involving three pilots. While the initial stages of the flight were clear, the pilot encountered deteriorating weather conditions, including heavy cloud layers and convective activity.
During the flight, the pilot navigated between cloud layers, at one point climbing to approximately 9,300 feet. At 12:13 local time, while at 12,250 feet, the aircraft entered a high-speed descent. The aircraft's pitch attitude became sharply nose-down, and the bank angle increased to 160 degrees. The airspeed accelerated rapidly from 130 km/h to over 550 km/h, far exceeding the aircraft's structural limits. At an altitude of approximately 5,000 feet, the microlight suffered an in-flight rupture. The aircraft struck the ground near Saint-Pierre-Roche, resulting in the fatal injury of the pilot and the destruction of the aircraft.
The investigation
The BEA examined flight data from the aircraft's Dynon avionics suite, radio communications with the Clermont-Ferrand flight information sector, and meteorological charts. The investigation also reviewed the pilot's medical history and the statements of the other two pilots involved in the group flight. Investigators analyzed the wreckage to determine the sequence of the structural failure and examined the aircraft's airframe parachute system, which was not deployed prior to impact.
Findings
- The pilot likely lost control while flying in the absence of external visual references, potentially within a towering cumulus or cumulonimbus cloud.
- The extreme airspeed reached during the descent caused the structural failure of the airframe.
- A deterioration in pilot performance, potentially due to altitude hypoxia or medical factors, may have prevented the pilot from regaining control or activating the airframe parachute.
- The pilot's flight preparation was insufficient, as the focus was on favorable conditions at departure and arrival rather than the deteriorating weather en route.
- The "group effect" and a desire to complete the flight despite worsening forecasts likely contributed to the decision to continue the mission.
- The presence of icing in the cloud layer cannot be ruled out as a contributing factor to the loss of control.