The National Iron & Steel Heritage Museum
USCGC Polar Star (WAGB-10)
Builder: Lockheed Shipbuilding and Construction Company (Seattle, Washington)
Commissioned: 1976
Length: 399 feet
Beam: 83.5 feet
Displacement: 11,000 tons
Speed: 18 knots (21mph), 3 knots (3.5mph) in 6-foot ice
Ice Capacity: 21 feet (ramming), 6 feet (continuous)
Polar Class

Other Characteristics: Polar Star has four different methods of electronic navigation to overcome the difficulties of high-latitude operations and a computerized propulsion control system to manage nine generators and three turbines.  The shell plating and associated internal support structure are fabricated from steel that has especially good low-temperature strength.  The part of the hull designed to break ice is 1.75 inches thick in the bow and stern sections.  The hull shape is designed to maximize icebreaking by efficiently combining the forces of the ship’s forward motion, the downward pull of gravity on the bow, and the upward push of the buoyancy of the stern.  The curved bow and heavy weight allow the vessels to force ice edges to break off downward.

History: During Antarctic deployments, Polar Star’s primary missions include breaking a channel through the ice to resupply the McMurdo Research Station in the Ross Sea.  She is the only U.S. ship large enough to break the heavy sea ice to access McMurdo.  Polar Star also serves as a scientific platform with five laboratories and accommodations for up to twenty scientists.  “J” shaped work cranes and work areas near the stern give scientists the capability to do at-sea studies of geology, volcanology, oceanography, sea-ice physics, and other disciplines.

Photograph: Polar Star Antarctic trip, February 16, 2006.  The icebreaker sits hove-to outside McMurdo Station, Antarctica.  (Source: PA2 Mariana O’Leary, United States Coast Guard)