The Transportation Safety Board of Canada (TSB) has published an incident report on a lifeboat release hook failure during a drill on the passenger ferry ‘Northern Ranger’ in October 2017, which led to minor injuries. The failure was linked to poor compliance with SOLAS and the operator’s safety manual.
On 11 October 2017, the starboard lifeboat of the passenger ferry Northern Ranger was undergoing operational testing at the dock in Nain, Newfoundland and Labrador, when its forward release hook failed.
While the crew members were lifting the lifeboat to the vessel’s embarkation deck, the forward release hook suddenly released and the lifeboat swung downward, bow first, and hung over the water from the aft release hook and fall. Four crew members were onboard the lifeboat at the time of the occurrence. One of the crew members fell through the lifeboat’s forward hatch and into the water; the other three crew members remained inside. All four crew members were recovered and their injuries were treated in hospital.
Probable causes and contributing factors
– The forward release hook’s safety defence failed and therefore did not meet the requirements of the Life-Saving Appliance (LSA) Code and SOLAS, 1974 (as amended).
– The lifeboat’s forward release hook was not reset according to the instructions in the operator’s manual.
– During the release hook resetting procedure, the forward release hook lock-position indicator was obscured by the end link, which led the operator to assume that the hook was in the locked position when it was not.
– The forward release hook’s blocking lever was bypassed, allowing the locking plate to rise without the hook’s tail being secured in its locking plate socket.
– This allowed the operator in the lifeboat to reset the on- or off-load release mechanism. This reset was used as confirmation that both the release hooks were in the lock position, and that the release mechanism and both forward and aft release hooks were secured. However, the forward release hook was not in the locked position and was unsecured.
– The bypassed blocking lever allowed the operator in the lifeboat to reset the on- or off-load release mechanism, giving lifeboat operators the impression that the release mechanism and both forward and aft release hooks were secured.
– The end links and release hooks initially supported the load of the lifeboat, reinforcing the crew’s impression that both release hooks were secured.
– The unsecured forward release hook initially supported the lifeboat’s load because of the deformation and friction between the contact points of the end link and release hook. The 28 mm diameter end link did not create a sufficient moment to overcome this friction and open the unsecured release hook.
– The crew used 28 mm diameter end links, which were of a smaller diameter than was needed for the release hooks to function as designed. Given the increased friction, the moment was insufficient to open the unsecured forward release hook.
– The sudden vibration through the forward davit wires decreased the friction between the forward release hook and the 28 mm end links’ contact points, allowing the hook to release.
– During the lifeboat’s retrieval, the davit wires of the forward fall were twisted. As the twist released, the fall rotated suddenly, causing a vibration throughout the fall and forward release hook. This vibration decreased the friction between the forward release hook and end links’ contact points, allowing the hook to release.
More findings from the report:
– When crews do not follow original equipment manufacturer instructions, there is a risk that equipment will not operate as designed.
– If a release hook’s blocking device is bypassed during the resetting procedure, although the on- or off-load release mechanism can be reset and safety pins inserted, there is a risk that the hook will not be secured.
– If operators are unable to verify the alignment of position indicators, there is a risk of operator error.
– If crews use components that have not been included in the engineered design of vessel equipment, there is risk the equipment will not function as designed.
– If companies use release hooks of the model and type used in this occurrence, there is a risk that their life-saving equipment will not be in compliance with SOLAS, 1974.
– If a manufacturer’s drawings and operating instructions contain discrepancies, operators might modify operating procedures, increasing the risk of injury or damage.
– Without precise engineered documentation regarding vessel equipment, there is a risk that equipment will be assembled in an unsafe manner.
– Life-saving equipment documentation and on-board signage was not in the flag state’s 2 official languages (English and French).
– At the time of the occurrence, the crew members in the lifeboat were not wearing personal flotation devices, lifejackets, or seatbelts.
Following the incident the Transportation Safety Board of Canada (TSB) issued a safety advisory letter (MSA 04-18) regarding release hooks model JXN-1 to the following:
– Jiangsu Jiaoyan Marine Equipment Co., Ltd.,
– RINA Classiﬁcation Society,
– Nunatsiavut Marine Inc.,
– Transport Canada (TC) Marine Safety and Security, and
– the members of IACS.
Shortly after the occurrence, the company implemented a corrective action prohibiting the crew from being in lifeboats during retrieval.
On 19 March 2019, TC issued a Ship Safety Bulletin to inform the marine community of safety measures concerning life-saving appliances.
At the same time, TC released FlagStateNet FSN 01-2019 to bring this incident to the attention of inspectors and surveyors.
TC also provided guidance material to all marine safety inspectors and recognized organization surveyors in regard to monitoring vessels equipped with these life-saving appliances.
Read the report in full: TSB-Marine-Transportation-Safety-Investigation-Report-M17A0391-Lifeboat-release-hook-failure-2020_02