Commodore Clipper - Marine Accident Investigation Branch

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vessel’s port side, transferring to form an equivalent wedge of water weighing 150
tonnes, would have caused a 5° list. The intact stability criteria could have still been
met with the vessel listing to angles greater than 5° list and with larger weights of
water. A damaged stability model, with greater capability than either the information
held on board Commodore Clipper or the simplified analysis conducted by the MAIB
(based on the same information), would be required to calculate the maximum angle
of list that could have been reached safely.
1.11.6 Requirements for prevention of fire-fighting water accumulating in ro-ro
spaces
SOLAS regulation II-2/20.6.1.4 16 highlights the potential serious loss of stability that
could arise from the accumulation of large quantities of water on deck during the
operation of a water-spraying fire-extinguishing system. Regulation II-2/20.6.1.4.1.1
requires that deck drains should be fitted to spaces above the bulkhead deck 17 on
passenger ships to ensure that such water is rapidly discharged directly overboard.
Regulation II-2/20.6.1.4.1.2 states that for cargo ships, where the requirements for
clearing such water cannot be met, the adverse effect upon stability of the added
weight and free surface of water shall be taken into account as deemed necessary
by the Authority in its approval of the stability information. Such information shall be
included in the stability information supplied to the master as required.
In June 2009, IMO circular MSC.1/Circ.1320 18 provided guidelines for SOLAS
regulation II-2/20.6.1.5 regarding the requirement for effective measures to ensure
floating debris does not block drains in spaces where fixed water-based fireextinguishing
systems are provided; this SOLAS regulation came into effect on
1 January 2010 for ships constructed on or after that date, with existing ships to
comply by the first survey thereafter. The circular recommended that an easily
removable screen or grating should be installed over each drain, raised above the
deck or installed at an angle to prevent large objects from blocking the drain.
A large mesh box, that could be fitted over existing drains and met the requirements
of MSC.1/Circ.1320, had been trialled on Commodore Clipper. The trial was
considered acceptable but the prototype had been removed to provide a pattern for
the remainder to be fabricated in good time to meet the required deadline.
1.12 TECHNICAL INVESTIGATION
1.12.1 Examination of the fire scene
Once the trailers and cargo debris were removed from the main vehicle deck,
there was no evidence of a seat of fire in the vessel’s structure or major items of
equipment. The freight trailers and their cargoes provided the vast majority of the
available combustible material.
Most of the fire-damaged trailers, apart from GC13-1, were refrigerated units, and all
were inspected as they were removed from Commodore Clipper. Trailers FS61 and
GC13-1 were hard-sided, and generally only had external structural damage where
burning cargo from neighbouring curtain-sided trailers had fallen onto them. Burning
debris on the deck had charred the tyres on the right-hand side of GC13-1 19 , causing
them to delaminate in places (Figure 16).
16 SOLAS amendments 2008 and 2009, Resolution MSC.256(84)
17 Bulkhead deck is the uppermost deck to which the transverse watertight bulkheads are carried (which for
Commodore Clipper, is the main vehicle deck)
18 Guidelines for the Drainage of Fire-Fighting Water from Closed Vehicle and Ro-ro Spaces and Special
Category Spaces of Passenger and Cargo Ships, 11 June 2009
19 All damage to trailers is described in relation to the trailer’s normal road-going orientation. Unaccompanied
trailers were reversed onto Commodore Clipper, so the rear of the trailer would have been pointing towards the
bow of the vessel and the towing end pointing to the stern.