What happened
On December 13, 2015, a Fournier RF 5 motor glider departed Rottweil (EDSZ) at 14:35 local time, carrying a pilot and one passenger. The flight was intended to be a cross-country trip to Trier-Föhren (EDRT).
Radar data tracked the aircraft following a route through Bingen and along the Rhine. As the flight progressed, the aircraft entered an area characterized by low cloud ceilings and poor visibility. After passing through the Rhine Valley, the aircraft turned toward the A61 motorway. At approximately 16:10, while flying near the Koblen and Winningen area, the aircraft struck a guy wire of a 280-meter-tall transmission tower. The impact with the cable, which was approximately 70 meters above the ground, severed the fuselage of the Fournier RF 5 into two pieces. The aircraft crashed to the ground, resulting in two fatalities and the destruction of the aircraft. The collision also caused damage to the transmission facility.
The investigation
The BFU investigation reconstructed the flight path using radar data and examined the wreckage at the scene. Investigators found that the aircraft's fuselage had been split longitudinally and that a segment of the control linkage was bent by a diameter of 50 mm, matching the diameter of the transmission tower's guy wire.
Meteorological analysis revealed that the region was under the influence of a weather front, bringing low clouds, rain, and fog. While weather at the departure point in Rottweil was favorable, conditions along the route had deteriorated significantly. The investigation also noted that the pilot, an experienced professional with over 4,000 total flying hours, had previously flown this route multiple times. The investigation found no evidence of impairment or loss of consciousness prior to the impact.