Casualties unknown

2009-07-02: EUROCOPTER AS 350 B3 (HB-ZBJ) — Walenstadt, SG, CH

Walenstadt, SG, CH

On July 2, 2009, an EUROCOPTER AS 350 B3 (registration HB-ZBJ) was involved in an aviation accident near Walenstadt, SG, CH. Investigators recorded the probable cause as: The accident is due to a police grenadier losing balance during his rappel exit and subsequently falling to the ground. The rappel exit technique imposed by the device in place contributed to the accident. This summary draws on records from the Swiss Transportation Safety Investigation Board (STSB / SUST).

Sourcesthe Swiss Transportation Safety Investigation Board (STSB / SUST)Primary reportUpdated 1785639345Data APIEditorial standards

A police grenadier fell after losing balance during a rappel from a hovering Eurocopter AS 350 B3 (HB-ZBJ) in Walenstadt, Switzerland. The exit technique imposed by the device contributed to the accident.

Incident Overview

On 2 July 2009, at approximately 16:35 local time, a police grenadier sustained serious injuries after falling from a Eurocopter AS 350 B3 helicopter (registration HB-ZBJ) during a rappel training exercise near Paschga, Walenstadt, Switzerland. The helicopter, operated by Heli Linth AG on behalf of the Cantonal Police of Zurich, was conducting a training flight for police grenadiers. The aircraft was not damaged, and no other persons were injured.

Sequence of Events

The training session involved two groups of police grenadiers. The second group began practical exercises at 16:02. The grenadier involved in the accident was positioned as the group leader on the right skid of the helicopter, with another grenadier behind him on the same skid and a third on the left skid. An instructor on board acted as the 'despatcher,' providing instructions to the pilot.

During the second rappel exercise, which was conducted over a bunker roof, the instructor reported that the first two grenadiers (one on each side) had left the skids. According to the involved grenadier, after leaving the skid, he was unable to establish the leg lock on the rappel rope. Consequently, he was supporting his entire weight with his hands. Due to his equipment adding approximately 20 kg to his body weight, he could not maintain his grip and began sliding down the rope. Despite wearing gloves, his hands became increasingly warm, and he eventually released the rope and fell to the ground.

The pilot, observing via a mirror, saw the grenadier stumble and fall, immediately ordering the instructor to abort the exercise. The second grenadier on the right skid remained in place, and the pilot landed at 16:38.

Findings

The investigation determined that the accident occurred because a police grenadier lost his balance during his rappel exit and subsequently fell to the ground. The rappel exit technique required by the equipment in use contributed to the accident. The helicopter was not damaged, and no third-party damage occurred.

Probable cause

The accident is due to a police grenadier losing balance during his rappel exit and subsequently falling to the ground. The rappel exit technique imposed by the device in place contributed to the accident.

Investigation report by the Swiss Transportation Safety Investigation Board (STSB / SUST). Original record: https://www.sust.admin.ch/inhalte/AV-berichte/2066.pdf. This page is a structured re-presentation; facts and quotes are in the Swiss Transportation Safety Investigation Board (STSB), Switzerland.