What happened
On June 23, 2024, a Shark 600F microlight, registration 22LE, departed Lannion airport for a scheduled sightseeing flight toward the island of Ouessant. The flight was operated by Air Trégor as a commercial venture. After initially climbing to 1,500 ft, the pilot descended to approximately 600 ft, likely attempting to remain below the cloud base.
During a series of turns and altitude changes, the aircraft entered a cloud layer, resulting in the loss of all external visual references. Flight data from the onboard EFIS units recorded a period of instability where the aircraft's speed dropped to 50 km/h and the angle of attack warning was activated. Following a period of significant vertical acceleration, the aircraft entered a steep, nearly vertical descent. The microlight struck the ground at high speed, resulting in two fatalities.
The investigation
The BEA examined the wreckage, the aircraft's Dynon EFIS units, and the engine parameters. Investigators found that the flight controls remained functional prior to impact and the airframe parachute had not been deployed. Analysis of the avionics revealed that autopilot servo messages ("ROLL SERVO OFFLINE" and "PITCH SERVO OFFLINE") had been recorded five minutes before the loss of control, suggesting a potential loss of power or communication to the autopilot system.
Meteorological data indicated that while the departure airport had marginal conditions, the planned route faced adverse weather, including low ceilings and reduced visibility. The investigation also looked into the regulatory status of the flight, noting that the operator was advertising commercial flights that exceeded the legal distance limits for local microlight operations.
Findings
- The pilot flew into weather conditions that were incompatible with VFR flight.
- The loss of external visual references led to a loss of control.
- The pilot likely descended to lower altitudes to avoid clouds, eventually entering the cloud layer.
- Pressure to complete the flight, potentially due to the presence of a passenger and a previous cancellation, may have influenced the decision to proceed despite the weather.
- The aircraft's autopilot functions may have been unavailable due to a potential circuit breaker issue.