What happened
While navigating through thick fog and stratus clouds over the Plateau, the pilot was executing an IFR approach to runway 25 at Grenchen Airport. After passing the Willisau VOR, the pilot performed a standard turn but inadvertently followed the 290° radial rather than the required 280° radial.
Upon reaching a distance of 7 NM as indicated by the DME, the pilot identified the deviation from the established approach path. In an attempt to correct the error, the pilot disengaged the autopilot and attempted to increase altitude. However, while the aircraft was in a landing configuration with the gear and flaps extended, it was unable to climb sufficiently. The aircraft type struck the wooded terrain of Mt Balmfluechöpfli, which sits at an elevation of 1,289 metres, approximately 12 km northeast of the destination airport. The impact caused the aircraft to disintegrate.
Findings
- The flight was operating in poor visibility due to heavy fog.
- The pilot deviated from the published radial during the approach procedure.
- The aircraft's configuration, with gear and flaps down, prevented the necessary climb to clear the terrain.
- The accident resulted in 1 fatality and 1 injury.