On the night of 6 October 2023, a chain link in the lifting arrangement for the dredging gear that was suspended from the raised port derrick on the UK registered scallop dredger Honeybourne III (PD905) failed. The gear fell without warning and struck a deckhand working on the deck below; the deckhand suffered serious head injuries and died on board.
The configuration of a chain on Honeybourne III led over a static pin as part of the quick-release gear for the lifting arrangement is commonly used on board scallop dredgers and beam trawlers. Such arrangements are known to have failed previously: in February 2021, a similar chain arrangement parted on board the beam trawler Cornishman (PZ512) causing the death of a deckhand.
Safety lessons
The recent recorded accidents and failures of chain links leading over a static pin as part of a quick-release mechanism indicate the significant risk of such arrangements failing when loads are applied to the chains. These arrangements can induce complex loading forces in the chain links, leading to excessive wear on the chain links and significantly reducing the chain strength.
The location of the chain links at the derrick head and the fact that the deterioration of the chain links may not be easily visible mean that it can be difficult to inspect and identify degradation of the quick-release arrangement.
The potential failure of chains used in this manner presents an unacceptable level of risk to crew members working on the deck below. as was the case with Honeybourne III.
Recommendations
A recommendation (2024/101) has been made to the Maritime and Coastguard Agency to conduct a focused inspection campaign on board UK scallop dredgers and beam trawlers fitted with derrick head quick-release mechanisms that incorporate chain to:
– raise awareness among skippers and crews of the significant hazards associated with the use of chain links passing over a static pin as part of the derrick head quick-release mechanism;
– confirm that the risk of a failure of the derrick head quick-release mechanism has been assessed, mitigated and documented by the owner, operator and/or skipper of the vessel;
– and verify that the crew are informed of the findings of the risk assessment and the measures taken for their protection in the event of a failure of the derrick head quick-release mechanism.
All owners, operators and skippers of UK scallop dredgers and beam trawlers that use chain as part of the derrick head quick-release mechanism on board their vessels have been recommended (2024/102M) to:
– urgently ensure that a suitable and sufficient assessment of the risk of a failure of the derrick quick-release mechanism chain has been undertaken and documented, noting the safety issues identified in this safety bulletin.
– that mitigations are identified and immediately implemented to reduce the risk to the crew associated with a failure of the derrick quick-release mechanism to a level that is as low as reasonably practicable;
– and, that the crew are informed of the findings of the risk assessment and the measures taken for their protection.
Chief Inspector of Marine Accidents, Andrew Moll OBE, said, “This is the second death that the MAIB is investigating as a result of a chain comprising part of a quick-release system at the derrick head failing under load and allowing fishing gear to fall onto crew working on deck. Today, I am urging the owners and operators of beam and scallop trawlers to take note of the dangers highlighted in this safety bulletin, and to take immediate steps both to inspect their vessel’s quick-release arrangements and to make any changes necessary to the equipment or its operation to ensure the safety of crew working on deck. The chain-over-pin arrangement has recently resulted in two deaths and there is no room for a do-nothing option.”
Download the Safety Bulletin:Honeybourne III - MAIB
