What happened
On July 23, 2014, a single-seat Sportavia-Pützer SFS 31 Milan motor glider departed from the Oppenheim airfield on Runway 20 for a local training flight. The takeoff was initially reported as unremarkable by the flight controller. However, shortly after the aircraft left the controller's field of vision, witnesses observed the glider banking in a left turn before stalling and impacting the ground approximately 800 meters southwest of the runway end. The impact occurred in a harvested grain field. The pilot sustained one serious injury, and the aircraft was destroyed.
The investigation
The BFU examined the wreckage and the flight conditions. The investigation found that the aircraft's takeoff mass was at least 455 kg, which exceeded the maximum permissible takeoff weight of 440 kg. The investigation also noted that the center of gravity was outside of the permitted limits. While the engine and airframe showed no signs of technical failure, investigators considered the possibility of fuel starvation due to vapor lock, given the high ambient temperature of approximately 28 degrees Celsius and the vibration of the fuel system during taxiing. The pilot's medical history and a previous long-term period of flight unfitness were also noted, though no direct link to the accident could be established.
Findings
- The aircraft was operating with an excessive takeoff weight and an out-of-limits center of gravity.
- The heavy loading and improper weight distribution favored a stall during the execution of a turning maneuver.
- The aircraft stalled during the initial climb phase, leading to the impact.