What happened
On August 5, 2015, a pilot was conducting a recreational flight in a Scheibe Uli ultralight aircraft, departing from the Degmarn airfield. The takeoff from the grass runway was initially unremarkable. However, during the circuit, witnesses observed the aircraft flying significantly lower than usual.
At approximately 10:55 AM, onlookers saw the aircraft pitch forward, briefly recover, and then pitch forward again. Shortly thereafter, the aircraft disappeared behind a line of trees. The aircraft struck a harvested field approximately 1,100 meters south-southwest of the airfield, impacting the ground nearly vertically with the nose of the fuselage. The impact resulted in the fatal injury of the pilot and the total destruction of the aircraft.
The investigation
The BFU investigation examined the aircraft's condition, the pilot's experience, and the environmental factors. The aircraft, a single-seat Scheibe Uli, was noted to have a sensitive flight characteristic, specifically regarding wind and thermals. The investigation found that the aircraft's pendulum elevator design caused it to pitch steeply forward during a stall.
Technical inspections revealed that the aircraft's emergency parachute system had been in use since March 2015 without a valid subsequent inspection. Additionally, the aircraft was missing a compass required by its minimum equipment list. While the pilot was a licensed flyer with 288 hours of experience on three-axis ultralights, he had only approximately two hours of flight time specifically in this aircraft. An autopsy of the pilot revealed no evidence of underlying medical issues contributing to the accident.
Findings
- The aircraft was highly sensitive to thermal and wind conditions.
- The aircraft's design led to a steep forward pitch during a stall.
- The pilot's experience with this specific aircraft type was very limited.
- The emergency parachute system was operating without a valid periodic inspection.