Positive: Worn mooring lines spotted and replaced before they parted

  • Safety Flash
  • Published on 2 October 2025
  • Generated on 5 October 2026
  • IMCA SF 18/25
  • 2 minute read

It was observed that mooring ropes had nearly reached breaking point.

What happened?

On a vessel alongside on a windy night, hourly walkarounds were being conducted as instructed by the Officer of the watch. During one of these inspections, it was observed that one of the mooring ropes had nearly reached its breaking point due to the strong wind and the structural characteristics of the berth.

What did they do next?

The crew member spotting the problem informed the Officer of the watch and the Bosun. The mooring rope that was at risk of breaking was replaced with a new one. Additionally, wooden boards were placed under the ropes that were rubbing against the bridge structure to minimize friction and prevent further wear.

What do we learn?

In adverse weather conditions, even the provision of additional mooring ropes cannot fully guarantee the vessel’s safety—particularly when no measures are taken at certain berths where friction may be a particular issue and ropes are likely to be in contact with rough surfaces.


Timely detection of such issues is crucial for ensuring the safety of the vessel. To prevent similar situations, it is may be necessary to increase the frequency of vessel walkarounds—especially during adverse weather conditions—and for the crew to exercise heightened vigilance.


The most effective preventive measure, however, would be the installation of protective equipment on the jetties by the port authorities to minimize rope friction and reduce the risk of mooring line damage.

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