What happened
On June 3, 2009, an Eurocopter AS350 B3, registration HB-ZJO, was performing commercial VFR external load operations near San Nazzaro, Switzerland. The aircraft was engaged in a series of rotations to transport materials from the Monti di Scaiano area to the "Sass di Sciatt" landing site. During the 24th rotation of the day, the crew was delivering a 920 kg construction barrack.
At the landing site, another helicopter, an AS350 B2 with registration HB-XVM, was also active. After the cargo was placed on the ground, the flight assistant assisted in unhooking the load. As the pilot of HB-ZJO began the climb for the next rotation, the flight assistant's right glove became snagged on the cargo hook. The assistant was lifted approximately 6 to 7 meters into the air. Although the pilot immediately aborted the climb and descended, the assistant was unable to maintain his grip after momentarily freeing his hand from the glove and was subsequently dropped from a height of about 4 to 5 meters, resulting in a fractured leg.
The investigation
The investigation examined the operational procedures at the landing site and the coordination between the personnel present. It was noted that several individuals were in the danger zone, including flight assistants from both aircraft and a truck driver. The investigation also reviewed the regulatory requirements for using the landing site, noting that the operator had not submitted the required flight notification to the local municipality.
Findings
- The primary cause of the accident was that the flight assistant became entangled with the cargo hook, which led to his fall.
- A significant contributing factor was poor coordination on the landing site, as the presence of an untrained truck driver in the danger zone was not managed, and he was not instructed to remain outside the hazardous area.
- The investigation also identified that the pilot had not announced his position on the local frequency, and the operator had not complied with local municipal regulations regarding flight notifications for that specific site.