Part 1 - Merchant Vessels - Marine Accident Investigation Branch

CASE 15
Navigating the Cut
Narrative
A large bulk carrier, in ballast, embarked a pilot
at the entrance to the port and headed upriver
on an ebb tide. The bridge was manned by the
master, second officer, helmsman, and a pilot
who had conduct of the vessel.
Just before the entrance to the locks, the
vessel was met by three tugs: two were made
fast forward and aft respectively; the third was
not made fast as it was to be used for pushing.
Dock
Diagram of lock system
Cut
As the vessel headed for the cut, the pilot
ordered dead slow ahead to reduce the
vessel’s speed astern and allow use of
the rudder to control her stern’s lateral
movement. When the vessel entered the
cut, the pilot noticed her stern drift towards
the port side wall. He ordered the third
tug to ‘push with full weight’, which was
acknowledged and implemented by the tug’s
master. The pilot also ordered the helm
The pilot then manoeuvred the bulk carrier
stern-first into the lock.
The vessel left the lock stern-first, under tow
by the aft tug. Once the bow was clear of the
lock, the pilot ordered the forward and aft
tugs to adjust the alignment of the vessel in
preparation for a transit through a narrow cut
(figure). The third tug was tasked to push on
the vessel’s port side as and when required by
the pilot.
42 MAIB Safety Digest 1/2012
Dock
Lock
‘hard-a-port’. However, these actions did
not prevent the vessel’s port quarter from
making contact with the sharp edge of a
counterweight ballast tank fitted on the cut’s
open and recessed swing bridge.
The contact occurred in way of a topside fuel
oil tank and caused a 1.5 metre gash in the
vessel’s side, which resulted in about 330
tonnes of heavy fuel oil spilling into the dock.