Lifeboat wire rope failure

During a five-yearly 110% load test of a lifeboat, taking place under third party supervision, the forward fall wire failed, resulting in the lifeboat falling and flipping upside down landing in the water below. 

There were no personnel onboard during testing and no injuries were reported. 

The lifeboat was recovered to shore.

Our member’s investigation noted that during maintenance of the lifeboat davit sheaves, the fall wire was removed by disassembling the three existing bulldog (“Crosby”) clamps on each wire termination on the davit.

Once all maintenance works were completed, the fall wire was reinstalled using the original bulldog clamps, which were clamped in the same position as the original termination.

Close inspection of the wire indicated that the fall wire had slipped through the bulldog clips and released from the thimble on the turnbuckle because:

• The grips were torqued in the exact same position they were before, therefore compromising the structure of the wire which was already flattened/deteriorated.
• The bolt grips were tightened without making reference to any minimum / maximum torque value specification.

Additionally:

• There had been inadequate preparation of the wire for termination.
• Bulldog clips had remained in use  since the installation of the lifeboat, as there was no regulatory or mandatory (Flag state) or company procedural requirement to perform replacement.
• There was no evidence that the bulldog clips were inspected prior to refitting.