Incident Overview
On February 17, 2011, at approximately 12:25 local time, a Eurocopter AS 350 B2 "Ecureuil" with registration HB-ZHI collided with the terrain at the Glacier de Tsanfleuron in the municipality of Conthey, Valais. The aircraft was operated by Heliswiss, Schweizerische Helikopter AG, based in Belp. The flight was a commercial Visual Flight Rules (VFR) operation transporting skiers and guides to the "Glacier 3000" ski area.
Operational Context
The pilot, a Swiss citizen born in 1967, held a Commercial Pilot Licence (Helicopter) and had approximately 1,560 total flight hours. The helicopter was configured for a high-density altitude operation at an elevation of 2,860 meters above sea level. Prior to the final approach, the pilot assessed that the aircraft's weight was within limits for hovering out of ground effect (HOGE) under the prevailing conditions.
Accident Sequence and Findings
The investigation determined that the accident occurred during a go-around maneuver when necessary visual references were missing. The Swiss Accident Investigation Board (SUST) identified two primary causal factors: the pilot's decision to attempt an approach in difficult conditions, which left little margin for error, and the pilot's distraction by passengers, which led to a high-risk maneuver. A contributing factor was insufficient oversight by the operating company.
Additionally, the landing site was located within a ski domain without clear markings or separation from ski runs, posing a latent danger to third parties. The accident resulted in four serious injuries among passengers and one minor injury to the pilot; no fatalities were reported. The aircraft was destroyed.