Public tours: Noon-7 p.m.: Friday, Aug. 24; Saturday, Aug. 25; and Sunday, Aug. 26.
Built: 1978, Tacoma, Wash.
Type of vessel: Bay class ice-breaking/multi-purpose tug.
Engines: Diesel-electric; bow thruster on barge.
Home port: Sturgeon Bay, Wis.
Normal operating area: Upper Great Lakes.
Crew: Five officers, two enlisted officers, 23 enlisted.
Mission: The U.S. Coast Guard Cutter Mobile Bay is one of four from its class currently assigned to the Great Lakes to assist with safe navigation, principally with ice-breaking in the winter. The 140-foot tug is also assigned a crane-equipped barge with which it conducts buoy maintenance during the warmer months.
Capabilities and equipment: The Mobile Bay's power plant and hull are both designed for ice-breaking service. It features a specialized hull design and "slick" bottom paint, plus a "bubbler" system that pumps air through openings in the hull below the waterline to reduce ice friction when it works its way through ice fields. At full power and using all four sections of the "bubbler" system, the Mobile Bay is capable of breaking up ice 30 inches thick in continuous operation. It primarily works in Green Bay, the Straits of Mackinac, and the St. Mary's River during ice-breaking season.
Other information: In 1992, the Coast Guard took delivery of Barge 12002, notched at one end for the Mobile Bay's bow to fit into it. In this configuration, the Mobile Bay works as a buoy tender, maintaining more than 100 floating navigation aids in upper Lake Michigan and Green Bay. The Mobile Bay's other missions include maritime law enforcement, search and rescue, pollution response, and homeland security.