What happened
On April 2, 2024, at approximately 09:28 local time, an Airbus Helicopters AS 350 B3, registration HB-ZCZ, was performing a commercial flight under Visual Flight Rules (VFR). The aircraft departed from the Croix de Coeur mountain landing site (LSYQ) and was en route to the Petit Combin mountain landing site (LSYP) in the Val de Bagnes region. During the approach or landing phase, the helicopter struck the ground at the Petit Combin site. The impact caused parts of the aircraft to slide down the northwest slope of the mountain. This movement triggered an avalanche that swept away the fuselage and the occupants, who were ejected from the aircraft during the event.
The investigation
The Swiss Transportation Safety Investigation Board (SUST) opened an investigation into the occurrence. The preliminary information establishes that the aircraft was operated by Air-Glaciers SA. The investigation focused on the sequence of events leading to the ground impact and the subsequent environmental reaction (the avalanche) that contributed to the severity of the incident.