Summary of incident
In May 2016, during a helicopter lifting operation to relocate a drill rig on a salt lake, two drill offsiders attached fibre loop slings to the corners of the drill rig base by looping them around the frame. Two fibre loop slings were then attached to opposite corners of the rig’s base for use as tag lines by the drill offsiders.
As the helicopter lifted the rig, an offsider’s leg became entangled in a tag line. He was lifted some distance before the helicopter pilot became aware of the situation. When the pilot reduced altitude to bring the offsider back to ground, he had untangled his leg and was holding on to the fibre loop sling with his arms. The offsider let go and fell 5 to 10 metres to the ground, injuring his back.
Direct causes
- The drill offsider’s leg became caught in the tag line as the helicopter was lifting the rig.
Contributory causes
- Fibre loop slings were used as tag lines.
- Neither drill offsider held the appropriate high risk work licences for conducting dogging or rigging operations.
- The risk assessment failed to identify the potential hazards associated with the task