What happened
On May 27, 2018, at approximately 12:40 PM, a pilot initiated a self-launch from the Schreckhof glider airfield in Reichenbuch, Germany. The aircraft, a DG-800B motor glider, was performing a private flight under Visual Flight Rules (VFR).
During the takeoff roll, witnesses observed that a tail dolly (a wheel used for ground maneuvering) was still attached to the rear of the aircraft. An attempt was made by a witness to warn the pilot via radio to avoid shutting off the engine while the dolly was still mounted, but the pilot did not respond, and no radio connection could be established via a relay station.
Shortly after takeoff, a witness near the eventual crash site noticed the aircraft flying level for several seconds after the engine had been shut down. The aircraft then entered a vertical dive, followed by an accelerating, corkscrew-like motion. Approximately five minutes after takeoff, the aircraft struck the ground at an altitude of roughly 500 m AMSL. The impact resulted in one fatality and the total destruction of the aircraft.
The investigation
The BFU investigation examined the aircraft's flight path using FLARM data and analyzed the wreckage. The aircraft was found heavily damaged by fire at the crash site. The engine and propeller unit had been retracted, and the engine covers were closed.
The investigation also reviewed the aircraft's weight and balance. At the time of the accident, the total mass was approximately 458.5 kg. The investigation determined that the center of gravity (CG) was located at 0.4061 m behind the reference datum. This position was outside the manufacturer's specified allowable range, which is between 0.2380 m and 0.4380 m.
Findings
- The aircraft was operating with an out-of-limits center of gravity.
- The CG was located behind the aft limit of the permissible range.
- The presence of the tail dolly on the aircraft during flight may have contributed to the instability.
- The pilot failed to respond to radio warnings regarding the tail dolly during the takeoff roll.