Grace Marie underway before the sinking (Photo: Paul Spillane via NTSB) 
Commercial Mariner - Fishing & Aquaculture

Failure of doubler-plated hull likely cause of sinking of fishing vessel off Massachusetts in 2022

Baird Maritime

The failure of the doubler-plated hull under the engine room likely caused the flooding and sinking of a fishing vessel near Gloucester, Massachusetts last year, the National Transportation Safety Board (NTSB) said recently.

The stern trawler Grace Marie was transiting to fishing grounds on July 8, 2022​, when the engine room began flooding. The seven-person crew were unable to remove the water with the vessel's bilge pumping system.

The crew abandoned the vessel in a life raft and were rescued by a Good Samaritan vessel.

The trawler eventually sank and was a total loss valued at US$650,000. No injuries were reported.

​The external area of the hull along the keel and under the engine room was covered with steel doubler plating to cover and reinforce areas of deteriorated steel. It was installed eight to 10 years before the vessel sank.

The NTSB said it is common for uninspected commercial fishing vessels such as Grace Marie to use doubler plating to repair and reinforce damaged or wasted underwater hull sections.

Doubler plate repairs can lead to increased stress concentrated in the area of the repair. Doubler plating also inhibits the ability to assess the true condition of the hull.

The NTSB determined the probable cause of the flooding and sinking of Grace Marie was uncontrolled flooding of the engine room from an undetermined source, likely a failure of the doubler-plated hull below the engine room.

"Although doubler plating can be used as a temporary repair solution, it is not generally suitable as a permanent repair for a vessel's hull," the report said. "Vessel owners should crop out wasted steel on the hull and replace it by inserting new plating instead of covering it up with doubler plating."

Marine Investigation Report 23-13 is available online here.