What happened
On May 30, 2018, a Scheibe SF 25 C motor glider departed from the Herten-Rheinfelden landing field (EDTR) for a private flight. The pilot, accompanied by one passenger, intended to fly toward Konstanz. During the takeoff roll on runway 06, witnesses observed the aircraft lifting off between the halfway marker and the end of the runway, noting that it gained altitude very slowly.
The pilot had planned to abort the takeoff if the aircraft had not rotated by the halfway marker. After clearing a line of trees perpendicular to the flight path, the pilot experienced a loss of altitude. Near the A861 motorway, the aircraft stalled over the left wing, causing the right wing to strike overhead power lines. The aircraft subsequently crashed into dense bushes and trees at the edge of a field.
The aircraft sustained heavy damage and came to rest upside down. Both occupants were able to exit the wreckage on their own. The pilot sustained serious injuries, while the passenger suffered minor injuries.
The investigation
The BFU investigation focused on the aircraft's performance, weight and balance, and the environmental conditions at the time of the accident. Investigators examined the wreckage, including the wing structures and the cockpit controls. The investigation also reviewed the pilot's flight experience, the aircraft's maintenance history, and the meteorological conditions.
Findings
- The aircraft was operating at an overweight condition. The takeoff mass was calculated at 669.37 kg, which exceeded the maximum takeoff mass of 610 kg.
- The center of gravity was also outside of the permitted range. The calculated center of gravity was 2.132 m, while the allowable range was between 2.143 m and 2.334 m.
- High ambient temperatures (28°C) and the low-powered nature of the motor glider contributed to the degraded takeoff performance.
- The aircraft's right wing struck power lines, which led to the loss of control and subsequent impact with the terrain.