A large cargo vessel was at anchor. The opportunity was taken to carry out a drill of launching the vessel’s rescue boat. The boat is an open dory, made of glass reinforced plastic. For lifting, it has three eye-plates, one forward, and one each side at the after end. Each eye-plate is bolted to the hull with four bolts. The heads of the bolts are visible but not the shanks or nuts. The boat is lifted by a single arm davit, with a three-part wire bridle, with one part to each of the eye-plates.
The boat’s crew of four were wearing boiler suit, safety boots, helmet and life jacket. The boat was swung out with the four crew members on board. As lowering commenced, the eye-plate on the port side aft suddenly detached from the hull. The boat was left hanging starboard side up. Three of the boat’s crew plummeted into the sea, a distance of approximately 12 metres. The officer in charge of the boat was left hanging on. Having ascertained that this officer was able to remain secure, the boat was lowered to the water and the three crew members were recovered, fortunately without long-term injury.
Subsequent examination showed that all four stainless steel bolts had failed.
Photo1: The rescue boat after it had been recovered back on board. The large webbing strap had been rigged whilst the boat was in the water to replace the third part of the bridle which is hanging loose.
Photo 2: The detached eye-plate.
Photo 3. Two of the failed bolts. The other two had similarly failed.
The ship’s manager arranged an urgent survey with the boat manufacturer on two vessels with the same rescue-boats of similar age. The bolts and eye-plates were found to be in satisfactory condition. At the time of publication of this newsletter, the manufacturer is analysing the broken bolts to determine the cause of the failure. Possibilities include a production error with these bolts or galvanic action.
We are very grateful to the ship manager for sharing this information at an early stage after the incident. If any other mariners or managers have experienced similar failures, we would like to hear from you.