USS Glacier (AGB-4)

USS Glacier, hull AGB-4 and later USCGC Glacier (WAGB-4), was an icebreaker that Ingalls Shipbuilding built at Pascagoula, Mississippi, for the United States Navy. She was launched on 27 August 1954 and commissioned on 27 May 1955, and she is the only icebreaker of the Glacier class. Her designers treated her as an improved Wind-class icebreaker, larger and more powerful, with a hull built for great strength, a sloping forefoot that let her ride up onto heavy ice and break it by weight, rounded sides, and heeling tanks that rocked the ship free of the pack. Diesel-electric machinery drove her because it was controllable and resistant to damage, and when built her single armature direct current motors were the largest of their kind installed on a ship. She served in the first Operation Deep Freeze expeditions to Antarctica, where she cut channels for supply ships and was the first icebreaker to pass through the frozen Bellingshausen Sea. The Navy transferred her to the Coast Guard in 1966, and she made many more polar voyages before decommissioning in 1987. She was sold for scrap in 2012. Ingalls is now a division of Huntington Ingalls Industries.