The U.S. Coast Guard’s 140-foot icebreaking tug, USCGC Mobile Bay (WTGB-103) departed the Coast Guard Yard in Curtis Bay, Maryland, Oct. 1, following completion of its service life extension project as part of the In-Service Vessel Sustainment (ISVS) Program.
Mobile Bay is the eighth of nine 140-foot icebreaking tugs to undergo service life extension work through ISVS. The work will extend each cutter’s service life by 15 years and includes upgrades to propulsion and electrical systems, replacement of the boat-launching davit and habitability improvements.
Mobile Bay will return to Sturgeon Bay, Wisconsin.
Mobile Bay is one of two ships in her class that has been equipped with a 120-foot Aids-to-Navigation barge operating on the Great Lakes. The vessel was specifically designed to carry out icebreaking missions, but also carries out missions in Search and Rescue (SAR), Environmental Pollution Response, Maritime Law Enforcement and Homeland Security.
Bay-class tugboats can proceed through fresh water ice up to 20 inches (51 cm) thick, and break ice up to 3 feet (0.91 m) thick, through ramming. These vessels are equipped with a system to lubricate their progress through the ice, by bubbling air through the hull.
The tugs entered service in the 1970s.