No fatalities

Helicopter Hovering Incident Injures Ground Personnel in Switzerland (HB-ZRE)

Himmelried, SO, CH

On May 24, 2010, an EUROCOPTER DEUTSCHLAND GMBH MBB-BK 117 C-2 (registration HB-ZRE) was involved in an aviation accident near Himmelried, SO, CH. No fatalities were reported. Investigators recorded the probable cause as: The accident was caused by a rotten branch breaking due to the helicopter's downwash during a winch mission and falling on people located underneath. This summary draws on records from the Swiss Transportation Safety Investigation Board (STSB / SUST).

Sourcesthe Swiss Transportation Safety Investigation Board (STSB / SUST)Primary reportUpdated 2026-10-18Data APIEditorial standards
Aircraft registered HB-ZRE
Aircraft registered HB-ZRE. Photo: Alexander Flühmann ( Xenomorph at German Wikipedia ) / CC BY-SA 3.0, via Wikimedia Commons

A Swiss air ambulance helicopter's downwind broke a rotten branch during a winch operation, injuring two people on the ground in the Chaltbrunnental valley on May 24, 2010.

Incident Overview and Aircraft Details On May 24, 2010, a Eurocopter MBB-BK 117 C-2 (EC145) helicopter, registered as HB-ZRE and operated by Schweizerische Luft-Ambulanz AG, was involved in an incident in the Chaltbrunnental valley, Himmelried/SO, approximately 13 km south of Basel. The aircraft, a twin-engine multi-purpose helicopter manufactured in 2003, was conducting a commercial VFR mission in hovering flight at an altitude of 350 m/M. The pilot, a Swiss national born in 1959, held a commercial pilot license for helicopters and had over 10,300 total flight hours. The helicopter was not damaged in the incident, and there was no third-party property damage reported.

Probable cause

The accident was caused by a rotten branch breaking due to the helicopter's downwash during a winch mission and falling on people located underneath.

Investigation report by the Swiss Transportation Safety Investigation Board (STSB / SUST). Original record: https://www.sust.admin.ch/inhalte/AV-berichte/2089.pdf. This page is a structured re-presentation; facts and quotes are in the Swiss Transportation Safety Investigation Board (STSB), Switzerland.