What happened
On May 30, 2009, a two-seat Schleicher ASK 21 glider departed from the Kamp-Lintfort airfield using a winch launch. The flight, which included two occupants, initially proceeded into the southern circuit area where several turns were completed. After approximately twelve minutes of flight time, the pilot began the approach to land.
During the final approach, the aircraft encountered significant sinking. While approaching the airfield from the west at a low altitude, the glider's right wing struck trees approximately 100 meters before the airfield boundary. This impact caused the aircraft to rotate 180 degrees, after which it struck the roof covering of a swimming pool. The impact destroyed the cockpit canopy, and a structural beam from the roof penetrated the rear cockpit area, causing one person to be seriously injured.
The investigation
The BFU investigation examined the aircraft, the pilot's experience, and the meteorological conditions at the time of the accident. The pilot held a valid license and possessed approximately 500 total flight hours, including ten hours of experience specifically with the Schleicher ASK 21 model. The aircraft was in good operational condition, having undergone its last annual inspection in March 2009, and no technical defects were identified during the examination.
Meteorological data indicated visual flight rules (VFR) conditions with light cloud cover. However, witnesses reported very gusty winds originating from between 70 and 100 degrees at speeds of 12 to 18 knots, creating challenging flying conditions.
Findings
- The primary cause of the accident was the pilot's incorrect estimation of altitude and obstacle clearance during the approach under challenging wind conditions.
- High wind gusts contributed to the aircraft's descent and subsequent loss of control during the approach.
- The impact with the swimming pool structure led to the severe injury of the rear passenger due to structural penetration into the cockpit.