Surveys of a 55 year-old dumb barge did not identify the lack of stability data and bending moment information, nor required an inspection in drydock says an MAIB preliminary report on the sinking of the Henty Supplier follwoing catastrophic hull failure at 1313 BST on 19 July 2010.
Says the MAIB: “Buckling of the hull leading to a transverse split along a cross-deck weld adjacent to hatch coamings in way of number 4 cargo tank.
The dumb barge Henty Supplier loaded with approximately 1850m³ of gas oil suffered a catastrophic failure of her hull while alongside Huskisson Dock in Liverpool. Approximately 50m³ of the gas oil spilled into the dock, but was quickly contained by terminal and port authority personnel. There were no injuries but the barge was a constructive total loss.
The barge was purchased by Henty Oil Ltd in 2004 and lay alongside in Liverpool until entering service as a floating oil storage vessel in 2006. Her suitability for this use was confirmed by annual ‘fit for purpose’ surveys conducted in accordance with the port’s regulations. The surveys did not identify the lack of basic stability and bending moment information, or require the barge to be inspected in dry dock.
It is probable that the structural failure of the hull resulted from long-term fatigue compounded by the distribution of the cargo, which would have induced a near maximum bending moment with the barge in a sagged condition. There were no written procedures for the loading or discharge of the barge’s cargo.
The Deputy Chief Inspector of Marine Accidents has written to Henty Oil Ltd advising that, when using a barge for oil storage and distribution purposes in the future, all cargo is loaded and discharged in accordance with written procedures, taking into account relevant stability and bending moment limitations, and industry best practice.
The Deputy Chief Inspector of Marine Accidents has also written to Mersey Ports strongly advising it ensures that all ‘fit for purpose’ surveys are carried out to a common standard and give due consideration to a vessel’s age and operation.