What happened
On May 22, 2015, a pilot was conducting a flight to take delivery of a newly purchased Bücker & Funk FK-12 ultralight, registration D-MYHS. The flight began at Saintes Thénac, with a stopover at Bar-Le-Duc, before proceeding to Sobernheim Domberg in Germany. On the return leg, the pilot departed Germany and stopped again at Bar-Le-Duc.
Shortly after departing Bar-Le-Duc for the second time that afternoon, the pilot radioed to announce he was returning to the airfield to rejoin a Zenair ultralight that had just departed. While attempting to locate the other aircraft, the FK-12 entered a right-hand turn. During this maneuver, the aircraft's airspeed decreased while the bank angle increased, leading to a loss of control. The aircraft struck a rapeseed field approximately 100 meters from the runway axis. The pilot was killed, and the FK-12 was destroyed.
The investigation
The investigation examined the wreckage and the flight path using GNSS data. The wreckage showed the aircraft impacted the ground with low horizontal speed and a slight nose-down attitude. No mechanical malfunctions were identified in the aircraft prior to the impact. While the aircraft was equipped with a ballistic parachute, it was not deployed.
The investigators also analyzed the pilot's physiological state and flight experience. On the day of the accident, the pilot had been flying for approximately seven hours with minimal breaks and had not eaten a full meal. Additionally, the investigation noted that while the pilot was highly experienced in other ultralight models, he had very little experience flying the FK-12 specifically.
Findings
- Pilot fatigue and nutrition: The pilot's performance was likely degraded by significant fatigue and inadequate food intake following a long day of flying.
- Inadequate altitude: The stall occurred during a turn at a height insufficient to allow for recovery.
- Flight characteristics: The pilot's limited experience with the specific handling characteristics of the FK-12 contributed to the loss of control as airspeed decreased during the turn.
- Operational pressure: A desire to complete the flight due to upcoming weather changes likely led the pilot to overlook the effects of fatigue.