Incident Overview
On January 19, 2002, at approximately 10:50 local time, a Piper PA-28-181 Archer II with the registration HB-PGS crashed on the Tsijiore Nouve glacier. The accident site was located about one kilometer north of the Pigne d’Arolla in the commune of Evolène, Valais, Switzerland, at an altitude of 10,000 feet.
Flight Details and Crew
The aircraft was operated by a private flying group based at Sion Airport. The flight was a Visual Flight Rules (VFR) pleasure trip involving four occupants: the pilot and three passengers. The planned route included overflying the Grande Dixence dam and the Pas de Chèvre pass before heading toward the Combin and Dolent peaks. At the time of departure, weather conditions were clear with good visibility, although the outside temperature was -4 °C.
Accident Sequence
After overflying the "lac des Dix," the aircraft entered a valley leading to the Tsijiore Nouve glacier. During a left turn, the plane grazed the névé (firm snow) and subsequently collided with the terrain. The impact caused the aircraft to come to rest on its back, balanced on the edge of a crevasse. All four occupants sustained injuries, with the pilot suffering severe trauma. Rescue operations were complex due to the difficult and dangerous access to the site, requiring helicopter hoisting for extraction.
Investigation Findings
The Swiss Federal Office for Civil Aviation (Bureau d’enquête sur les accidents d’aviation) determined that the primary cause of the accident was a collision with dirty and humpy firn. This impact was likely the result of an orientation error by the pilot. A contributing factor identified in the investigation was the use of unsuitable flying tactics in mountainous terrain after overflying the Pas de Chèvre pass.