What happened
On 8 March 2022, a Skyranger microlight, registration 12DM, was performing a flight test at Aix-Les Milles aerodrome in France. The pilot, who had recently performed several substantial modifications to the aircraft, intended to conduct two low-altitude right-hand circuits to verify the flight readiness of the modified machine. The aircraft was accompanied by a passenger.
Shortly after takeoff from runway 1er, the aircraft entered a steep nose-up attitude during the initial climb. Air traffic controllers observed the aircraft's ground speed dropping and noted that the aircraft appeared to be stalling. The microlight then entered a steep left bank and pitched nose-down, striking the ground with significant force. The impact resulted in one fatality (the pilot) and one severe injury (the passenger). The aircraft was destroyed in the crash.
The investigation
The investigation focused on the extensive modifications made to the aircraft by the owner prior to the flight. These changes included the installation of a more powerful 100 hp ROTAX engine, a new propeller, a new instrument panel, and a dual-stick control system. The pilot had also replaced the landing gear with larger wheels and modified the cockpit doors.
Investigators examined the wreckage and found that the flight controls, including the elevators, rudder, and flaps, remained functional and continuous. However, they noted that the elevator trim control utilized a bungee cord rather than a metal spring, which provided less retraction force. While the emergency parachute's pyrotechnic cartridge had been activated, the parachute failed to deploy, likely due to the stresses of the ground impact. The investigation also noted that the pilot had not requested a waiver to carry a passenger during a flight test, which regulations suggest should be conducted with a single occupant to minimize risk.
Findings
Several factors contributed to the loss of control during the takeoff sequence:
- Uncertain handling characteristics resulting from the recent engine, propeller, and control system modifications.
- Potential instability in the pitch or roll axes due to the aircraft's altered weight and balance.
- An unsuitable elevator trim position for takeoff or a potential defect in the trim control's friction that allowed it to move unexpectedly.
- Environmental conditions, specifically a crosswind component and light to moderate turbulence, which were not ideal for a flight test mission.