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Show Coast Guard's New Icebreaker Is Most Powerful in World Early in March the new coast guard icebreaker, Mackinaw, the most powerful ship of this type in the world, will clear a channel for ore boats through the canals and straits at the northern end of Lake Superior. Ordinarily a fleet of ships numbering as many as 100 is ice-locked ice-locked in Whitefish bay until spring. This year the much-needed iron from Minnesota's mines can be transported to the steel mills in m I . - , x'': sj; jr3 v- Great Lakes cities several weeks earlier than usual. While the lakes themselves are unfrozen all winter, except for a fringe from five to ten miles offshore, off-shore, the narrow waters in straits, canals and harbors are covered with j ice from December to April. It may i be from one to eight feet thick, ty- i ing up shipping all winter. Old-style j icebreakers have not been able to keep lanes open throughout the cold season. Ships of the Mackinaw type j should be able to do so. Vice Adm. Russell Waesche was quite satisfied with the ship's performance on a test run on Lake Huron last December, Decem-ber, and on a voyage from Lake Superior into Lake Michigan in January. Jan-uary. The icebreaker, built at a cost of $10,000,000, approximates in size a cruiser. She is 290 feet long with a beam of 74Vi feet and carries 12 officers of-ficers and 164 enlisted men. She is insulated throughout with cork to keep the crew comfortable in temperatures tem-peratures of 30 degrees below zero. In addition to 1-inch plates, the heaviest on the lakes, and six Diesel and two electric engines developing develop-ing a total of 10,000 horsepower, the Mackinaw has, two new ice-smashing devices. One is a bow propellor designed to suck the water out from under The coast guard Icebreaker Mackinaw opens a channel for freighters in the straits of Mackinac. The new ship easily crashed through thick ice during a trial voyage on the Great Lakes in January. the ice directly ahead of the ship. This makes it easier for the cutaway bow to break heavy ice into small chunks. The second is four inter-connected tanks among which water may be shifted to "trim" the ship fore and aft or "heel" it from port to starboard star-board to free it from the ice. Powerful Pow-erful pumps will shift 10,000 gallons of water from tank to tank in less than a minute, rocking the ship like a hobby horse. She plowed through 20 inches of solid blue ice as though it were soft butter on her first trial and also negotiated ne-gotiated without difficulty windrows of drifted ice as much as 10 feet high. She used full power only once and never had to call upon her special spe-cial ice-crushing equipment. Performance Per-formance exceeded expectations. |