What happened
On September 3, 2010, a Société Wassmer WA 54 Atlantic departed Oehna for Kempten-Durach. During the arrival phase, the pilot requested landing information for runway 35 and conducted a long right-hand approach. While flying west, south of Sulzberg, the pilot reported that the airfield was not in sight. Despite receiving navigational guidance from the tower controller, the pilot intermittently lost visual contact with the airfield.
Witnesses near the site observed the aircraft flying at a very low altitude and low speed, heading north toward Kempt and Durach. Approximately one nautical mile from the runway and a quarter mile left of the approach centerline, the pilot executed a sudden turn to the west. This maneuver caused the aircraft to strike the ground, with the left wing making initial contact. The impact resulted in two fatalities.
The investigation
The BFU examined the wreckage, radio communications, and GPS data. The investigation confirmed that the aircraft's weight and center of gravity were within limits and that the aircraft had been properly maintained. Analysis of the GPS data revealed a significant drop in airspeed during the final minutes of the flight. Radio transcripts showed the pilot was actively searching for the airfield, which was obscured by the low flight altitude and limited visibility of the terrain.
Findings
- The pilot was focused on locating the airfield, which likely led to a lack of awareness regarding the aircraft's decreasing airspeed.
- GPS data showed the speed dropped from 66 knots to 50 knots during the final approach.
- The aircraft entered an aerodynamic stall following an abrupt course change intended to avoid power lines.
- The low altitude prevented the pilot from recovering from the stall after the maneuver.