Rapid course change and cargo misassessment were causes of dredger capsizing

A rapid change of course and a misassessment of the make-up of the dredger’s cargo, was the reason for the sudden capsizing of dredger Sirius Høj (IMO 7032375) outside Bogense, Denmark, on March 10th 2018, according to a marine accident report from Danish Accident Investigation Board (Den Maritime Havarikommission – DMAIB).

The dredger was working off Bogense and was returning, fully loaded, to port. She suddenly sank with two crew members on board, one in the wheelhouse and one in the excavator’s cab, both of whom were rescued.

DMAIB immediately launched an investigation to find out what had caused the ship’s crew to fail to realize that the ship was in danger.

The investigation concluded that a combination of a rapid change of course and the weight of the cargo and material composition with free liquid surfaces, resulted in a heeling moment which was greater than the ship’s stabilizing momentum. The ship did not have the tools effectively to determine its stability after loading. Therefore the determination of the ship’s stability depended on an estimate. The load had a greater density than the crew expected. Because of this the skipper did not realize that the ship was in danger of falling as he made a quick and big change of course.”

1970-built, Denmark-flagged, 100 gt Sirius Hoj is owned and managed by Sirius Hoj of Horsens, Denmark.

Full report: https://www.dmaib.dk/media/9913/sirius-hoej-kaentring-den-10-marts-2018.pdf