A large container vessel was preparing to depart a berth ata major seaport in the afternoon. After completing cargo
operations, the vessel’s crew readied the ship for departure. Port movements had been delayed due to weather conditions, but once conditions improved, it was cleared to proceed.
Pilot Boarding and Setup (Early Evening):
After the weather-related delay, a Pilot boarded the vessel at approximately 1815 LT. The crew prepared to let go of the mooring lines. Forward, the team consisted of the Chief Officer (in charge of the operation), the Carpenter, the Ordinary Seaman (OS), and a Motorman. They had singled up, in readiness for the tug assistance. Mooring Line Arrangement for Tug Assistance.
(Shortly After Pilot Onboard):
The tug was to be secured at the vessel’s bow using a ship’s line. The Chief Officer supervised as the line was lowered under power from the mooring winch, passed around the bitts, and led through a multi-roller fairlead on the forecastle deck. The Carpenter prepared to rig the rope stopper once the line was in place, while the OS stood by at the bitts to make the line fast once the stopper was secured. Lowering the Tug Line and Attempted Securing.
(Before Incident):
With the line lowered toward the tug, the Carpenter positioned himself to fix the rope stopper, and the OS remained close to the bitts, ready to take turns on the line. The Chief Officer maintained visual contact with the tug and provided instructions, while the motorman assisted as needed. At this stage, communication and timing were critical to ensure the line was made fast safely. Sudden Tug Movement and Line Over-Tension
(Approx. 1915 LT):
Before the rope stopper could be properly engaged and without any clear signal from the vessel, the tug began to move away. This premature movement dramatically increased tension in the line, which had not yet been fully secured. Under sudden and excessive strain, the line stretched taut, jumped from its intended lead, and snapped back violently. The Carpenter, partially prepared to avoid the recoil, was still struck and thrown to one side. The OS, positioned closer to the snapback path, was hit with full force. Immediate Aftermath and Medical Response
(Shortly After 1915 LT):
Both the Carpenter and the OS sustained severe injuries. Emergency medical assistance arrived within minutes, and the injured crew members were evacuated from the ship’s forecastle deck to a waiting ambulance. The OS was declared deceased shortly after evacuation. The Carpenter, initially admitted to a local hospital and showing some signs of recovery, later succumbed to injuries.
In the meantime, the unmooring operation was halted, and the vessel remained alongside. Local authorities, including the Coast Guard, boarded the vessel and conducted an investigation. The vessel eventually departed the berth once formalities were concluded.
Questions
When discussing this case please consider that
the actions taken at the time made sense for all
involved. Do not only judge but also ask why you
think these actions were taken and could this
happen on your vessel?
- Does our SMS address these risks?
- What sections of our SMS would have been
breached if any?
- What specific communication methods should be
used to ensure that the tug and vessel are fully
aligned before lines are tensioned? - How can we standardize or improve the use of
hand signals, radios, or checklists to prevent
misunderstandings? - What steps can we take to verify line angles and
leads are optimal before applying tension? - What training or reminders can we provide so
crew members consistently position themselves
outside potential recoil paths?
- How can we encourage every crew member,
regardless of rank, to speak up if something
appears unsafe?
- How can we encourage the team to share “good
practices” observed during everyday operations
to further strengthen safety?
- Is our current equipment set-up (fairleads, bitts,
stoppers) ideal for minimizing snapback risk, and
what improvements could be made?
- How do we currently conduct pre-departure
briefings, and what additional information or
clarity could make them more effective?
- Would more frequent debriefings after routine
operations help us identify subtle improvements
and reinforce safe practices?
- What support do we need from management
(additional training, updated procedures, more
resources) to strengthen our mooring safety
practices?
- What immediate, actionable steps can we take
from today’s discussion to reduce snapback risks
and improve communication with tugs?
MSS Case September: Severe Mooring incident on container vessel
During an unmooring operation at a major seaport, a sudden tug movement caused a mooring line to snap back, resulting in severe injuries to two crew members and the tragic loss of one life.
For more Loss Prevention information, please contact:
Joakim Enström, Loss Prevention Officer
E-mail: joakim.enstrom@swedishclub.com
Each month, the Club’s Loss Prevention team issues a new safety scenario to assist members in their efforts to comply with international safety regulations and follow best practices.