UK MAIB: Leg injury while mooring

  • Safety Flash
  • Published on 3 June 2024
  • Generated on 22 April 2025
  • IMCA SF 11/24
  • 2 minute read

During unmooring operations, a crew person got caught in the bight of a messenger line mooring rope and was injured.

What happened?

During unmooring operations, a crew person got caught in the bight of a messenger line mooring rope and was injured. The incident occurred when a vessel was being prepared for departure. The worker was on the mooring deck, using a messenger line around the mooring rope to guide it onto a winch drum. Another worker was operating the winch remotely, with limited visibility of the first worker’s position near the drum. 

The messenger line suddenly snagged under the mooring rope and became wound onto the winch drum itself. Realising what had happened the injured person let go of the messenger line, but was unaware that it had formed a bight around their right leg. As the bight tightened, the injured person was pulled towards the winch drum and then dragged over it. The winch operator promptly stopped the winch. The injured person was disentangled from the messenger line and immediately taken ashore for medical treatment for a broken shin bone and other leg injuries.

Mooring rope around winch drum

Winch drum

Leg injury while mooring

Injured person

This photo may show graphic content.

What went wrong?

  • The long messenger line used to guide the mooring rope was able to reach the deck and wrap itself around the worker’s leg, leading to the incident.
  • The winch drum operator did not have clear “line of sight” to where the injured person was working.

Lessons

The MAIB noted:

  • Exercise caution around moving machinery – maintain a safe distance.
  • Avoid getting too close to rotating equipment and ensure that loose clothing or any objects that can become caught in it are kept clear.
  • When operating equipment remotely, it is crucial to have clear visibility of the people and surroundings involved. Whilst remote control allows operators to move around the deck while operating machinery from a safe distance, such as outside snapback zones and clear of suspended loads, it is important to maintain a line of sight to monitor the working area effectively and to be able to communicate with colleagues to prevent incidents and respond promptly to any potential issues.

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