What happened
On August 4, 2012, a 17-year-old student pilot was conducting her first solo flight in an ASK 13 glider at Quakenbrück, Germany. The flight began with a winch launch at 19:13 local time, which proceeded without incident. After the glider released from the tow cable at approximately 300 meters, the flight proceeded normally through the downwind leg.
However, during the approach, the aircraft entered an oscillating flight path. Flight data recorder analysis showed the aircraft's speed fluctuating between 61 km/ and 91 km/h, with the glider performing a series of unstable climbs and descents. Witnesses observed the aircraft performing a pitching motion around its lateral axis, at one point climbing nearly vertically before banking sharply. An instructor monitoring via radio instructed the student to "bring the nose below the horizon," but the instability continued. The glider eventually disappeared behind a residential building and a loud impact was heard. The aircraft struck several houses, causing damage to a residential structure, before coming to rest upside down on a paved parking area. The student pilot sustained fatal injuries, and the ASK 13 was destroyed.
The investigation
The BFU investigation examined the flight data from the onboard IGC logger, the aircraft's maintenance history, and the training records of the student. The investigation also reviewed the oversight capabilities of the regional aero club (LVN) and the local aviation authority. Investigators analyzed the medical history of the student, noting a diagnosis of exercise-induced asthma, though autopsy results confirmed that no acute asthma attack occurred and that the cause of death was solely due to the impact injuries. The investigation also looked into the adequacy of the theoretical and practical training syllabus provided by the club.
Findings
- The primary cause of the accident was that the glider was flown into an oscillating flight path, which the student pilot was unable to recover from.
- The student's practical training was insufficient, particularly regarding the management of unusual flight attitudes and special flight conditions.
- The theoretical training provided to the student was inadequate for the level of solo flight being undertaken.
- There was a lack of oversight by the regional training authority regarding the quality of instruction in member clubs.
- The student's solo flight was permitted without the required secondary instructor's approval.