What happened
On June 24, 2017, a private glider flight departed from the Bartholomä-Amalienhof airfield (EDPU) via a winch launch. The aircraft, a Grob G 103 C “TWIN III ACRO”, reached an altitude of 348 meters above ground level before the pilot released from the tow cable. Following the release, the pilot flew toward a wooded ridge located southwest of the airfield, performing several circles in the area to search for thermals.
Witnesses at the airfield observed the glider several times during its thermal search. One observer noted the aircraft at an altitude of approximately 200 meters and initially believed the pilot was beginning an approach for landing. Moments later, the witness observed the aircraft in a steep, nose-down dive. Other witnesses also reported seeing the glider enter a nearly vertical descent. The flight path data ended at 15:03 local time. The glider struck the ground in a forested area, resulting in the fatal injury of the pilot and the total destruction of the aircraft.
The investigation
The BFU examined the wreckage and analyzed flight path data from a FLARM collision warning device. The investigation confirmed the aircraft struck a clearing bounded by 5–7 meter tall trees, surrounded by taller deciduous trees. The wreckage was found with the longitudinal axis pointing north, at a 30-degree pitch.
Physical examination of the Grob G 103 C “TWIN III ACRO” revealed significant structural damage consistent with a high-impact ground collision. The forward cockpit area was destroyed, and the fuselage broke ahead of the tail section. The nose wheel was torn from the fuselage. While the left wing showed a 1-meter split at the torsion leading edge, the right wing remained structurally intact. The investigation found no evidence of technical malfunctions or mechanical defects in the aircraft's control systems or components.