What happened
On August 3, 2007, at approximately 16:15 local time, a Sport Aviacija Lak-19 glider departed on a winch-assisted thermal flight from runway 21 at the Metzingen glider airfield. The launch was conducted using a 230 hp Tost winch with a 4.6 mm steel cable.
Shortly after liftoff, the aircraft entered a steep climb, during which a leftward bank began to increase. At an altitude of approximately 40 meters, the glider experienced an abrupt roll to the left. The aircraft struck the ground with a significant longitudinal pitch, approximately 300 meters from the takeoff point and 90 meters left of the runway centerline. The impact was nearly vertical, with the nose of the fuselage making the initial contact. The crash resulted in the fatal injury of the pilot and the total destruction of the aircraft.
The investigation
The BFU investigation examined the aircraft, the flight conditions, and the pilot's experience. The Lak-19 was owned by a club and was properly maintained, having undergone its last annual inspection on April 21, 2007. The investigation confirmed that the aircraft's weight and center of gravity were within prescribed limits.
Regarding the pilot, records indicated a total flight experience of over 100 hours, including 13 hours on this specific model. The pilot had performed 15 winch launches at Metzingen within the preceding 90 days. Meteorological conditions at the time of the accident were favorable, with visibility being good, winds from 295° at 8 knots, and light cloud cover above 3000 ft.
Findings
- The aircraft struck the ground with a high degree of vertical pitch, causing the cockpit area to be crushed and the tail section to detach from the fuselage.
- The wing structure suffered multiple fractures and partial separation from the fuselage.
- The abrupt roll to the left at low altitude was the primary factor leading to the impact.