Overview
On July 10, 2004, a SA 315B Lama helicopter, registered as HB-XFX, operated by Air Zermatt AG, experienced an accident at Signalkuppe, near Zermatt, Switzerland. The aircraft was on a passenger transport flight from Heliport Zermatt to the Rifugio Margherita at 4554 m on Monte Rosa. The accident occurred at 10:57 local time at an elevation of 4320 m.
Flight History
The pilot received the daily schedule around 08:00 and performed preflight checks. After completing two material transport flights, the third flight—planned to carry a passenger and material to the Domhütte—was canceled due to adverse weather at the intended landing site (fog, wind, and snow). The next flight was a transport of scientists to the Margherita hut. The passengers arrived at the heliport around 10:00. The pilot shut down the engine after the previous flight and the helicopter was refueled with about 200 liters. The pilot started the engine, and the passengers boarded with assistance from a flight helper.
The helicopter departed at 10:43. Based on photographs taken by a passenger and eyewitness accounts, the flight proceeded normally toward the hut. The helicopter approached from the northwest over the Grenzgletscher at an altitude of 4100-4200 m, then climbed west of Signalkuppe, flying from south to north until reaching the hut's altitude. Shortly after passing the hut, northwest of Signalkuppe, it executed a left turn and descended southward, consistent with a reconnaissance circuit. After a period of no observation, the helicopter was seen south of Signalkuppe, clearly below the hut altitude, with its nose pointing northwest as it followed the ridge. Suddenly, the helicopter made a downward movement and contacted the terrain.
Aircraft and Impact
The helicopter struck a ridge, sustaining damage that caused a complete loss of engine power. It then fell onto the snow-covered glacier below. The helicopter was heavily damaged. The pilot and passengers sustained serious injuries.
Investigation Findings
The investigation determined that the accident resulted from a loss of control over the helicopter. The initial impact with terrain damaged the helicopter such that the engine failed. A contributing factor was the operation of the helicopter at the limit of its power under difficult environmental conditions.