What happened
On March 23, 1980, a Piper PA-28 aircraft, registered HB-PBI, departed Geneva for Sion under Visual Flight Rules (VFR). The flight was carrying a pilot, two passengers, and a dog. While flying over Lake Geneva, the aircraft encountered worsening weather conditions characterized by low clouds and reduced visibility.
As the aircraft reached the eastern end of the lake near Saint Gingolph, the pilot radioed Geneva Information to announce an intention to turn back due to the weather. Witnesses on the ground reported hearing the aircraft perform a turn that exceeded 360 degrees. During this maneuver, the aircraft lost visual contact with the ground and entered Instrument Meteorological Conditions (IMC). The aircraft subsequently struck the slopes of the Pic de Blanchard at an altitude of approximately 880 meters. The impact caused the aircraft to catch fire and resulted in the deaths of all 3 occupants.
The investigation
The investigation, conducted by the French Bureau d'Enquêtes-Accidents with assistance from Swiss authorities, examined the flight path, weather conditions, and the pilot's actions. Investigators analyzed radio communications, which confirmed the pilot's intent to return to Geneva. The wreckage analysis showed that the aircraft struck the mountain in level flight with its wings horizontal, indicating the engine was functioning normally prior to impact. The investigation also reviewed the pilot's experience and the meteorological reports for the Geneva and Sion regions at the time of the accident.
Findings
- The pilot did not consult official meteorological services for the route prior to departure, relying instead on a telephone inquiry regarding the destination weather.
- Several individuals at the departure airfield had specifically advised the pilot against flying due to the visible weather conditions.
- The aircraft entered IMC, which led to a loss of orientation and a navigation error.
- The pilot executed a turn in the wrong direction or with excessive rotation, leading the aircraft into the terrain rather than back toward Geneva.
- The pilot's relatively low flight experience contributed to the inability to maintain situational awareness once visibility was lost.