What happened
On September 19, 2019, a Schempp-Hirth Discus-2cT motor glider was performing a cross-country flight near the Boberg airfield in Hamburg. After approximately 45 minutes of flight utilizing thermal lift, the pilot began an approach to land at the home base.
As the aircraft reached an altitude of approximately 140 m AMSL near the runway threshold, the pilot initiated a left-hand turn. During this maneuver, the aircraft's airspeed decreased while the bank angle increased. Data logger records indicate that the airspeed dropped below the minimum safe threshold of 70 km/h. This led to a partial aerodynamic stall, causing the aircraft to abruptly bank to the left and enter a steep descent. The aircraft struck a meadow approximately 600 m south of the runway threshold, resulting in the destruction of the aircraft and the fatal injury of the pilot.
The investigation
The BFU examined the flight data logger, which remained intact following the impact. The investigation reconstructed the flight path, showing that while the aircraft maintained a relatively constant altitude during the initial phase of the turn, it was losing kinetic energy. The investigators also analyzed the aircraft's maintenance records, finding the airframe and engine to be in good condition and compliant with all regulations.
Witness accounts from the ground, including a fellow glider pilot, corroborated the sudden loss of control and the vertical nature of the descent. The investigation also reviewed the pilot's medical history and flight experience, noting that the pilot was highly experienced with over 880 flight hours, though he had undergone cardiac procedures in early 2019.