2011X66 Lifeboat Release Failure
| Lifeboat Release Failure |
ATSB Report 188 |
Another accident has occurred during lifeboat drill operations. The following is an extract from the Australian ATSB Report number 188. The full report can be obtained from www.atsb.gov.au
On 8 December 2002, Ma Cho arrived in Devonport, Tasmania, to discharge a part cargo of fertiliser at number four berth on the western side of the river. On 9 December, the master made the decision to conduct an abandon ship drill before the vessel was due to depart for Geelong.
The drill commenced at about 1540 and the starboard lifeboat was prepared for lowering to the water. At approximately 1548 the mate reported that the crew inside the lifeboat were seated and had fastened their safety belts. Lowering of the boat then commenced with one of the crew operating the davit winch brake from the deck. When the boat had been lowered approximately two metres from the davit head the after on-load release hook suddenly opened, releasing the after fall. The lifeboat's stern fell to leave the boat suspended vertically by the remaining forward fall with its stern swinging approximately five metres above the water.
The boat crew were shaken by the incident but remained secured in their seats inside the now vertical lifeboat. The second mate had sustained a small cut over his left eye. After the crew had disembarked, the lifeboat was lowered to the water to allow the onload release system to be inspected. It was found that the cable operating the after hook was not properly secured by the saddle clamp under the operating unit. Each time the actuating handle was operated, lost motion was induced by the cable sliding through the clamp and this meant that the after hook was not resetting fully. The cable clamp was temporary repaired and then the lifeboat was housed in its davit. The vessel was subsequently cleared to complete the voyage to Geelong.
The report conclusions include:
- The cable clamp securing the aft hook's operating cable adjacent to the operating mechanism had been modified which resulted in lost motion within the cable.
- As a result of the lost motion in its operating cable, the after hook had not been fully reset when the previous lifeboat drill was conducted on 2 November 2002.
- The design of the on-load release system was flawed with respect to the hook locking mechanism.
- The ship's safety management system was deficient with respect to both the operating and maintenance instructions and to crew training on the on-load release system.
The report makes a general recommendation to ISM Code accreditation authorities regarding ship safety management systems as they relate to on-load release systems. The report also recommends that the lifeboat manufacturer and classification societies review the design of the on-load release system.