| An Ice Breaker is a type of ship used by the Coast Guard to break ice in frozen waterways. They are the largest cutters operated by the Coast Guard and, as the name implies, are designed for specifically breaking ice. They have reinforced hulls, specially constructed bows and a system that allows the rapid shifting of ballast to increase the effectiveness of their icebreaking.
Currently, the United States Coast Guard has two Polar- class cutters that perform the ice breaking duties. Named the Polar Star (WAGB-10), and the Polar Sea (WAGB-11), they are the most powerful of the non nuclear ice breakers in the world. For any of you noders who are old salts, here are some of the vital statistics for both of these cutters.
Length:399 feet
Beam: 83.5 feet
Designed Draft: 28 feet
Top of mast above waterline: 138 feet
Displacement: (28' draft) 13,194 tons
Potable Water (100%): 26,586 gallons
General Cargo: 400 tons
Weight: 13,000 tons
Each of these bad boys are designed to break ice up to 21 feet thick. The crew consists of 134 men and women. They carry 1,359.200 gallons of propulsion fuel which gives them a range of 28,275 nautical miles at a speed of 13 knots. The diesel plants in the ships engines are capable of producing 18,000 shaft horsepower and the gas turbine produces about 75,000 horsepower.
These ships are used mainly in the Arctic and Antarctic. They provide scientific research as well as re-supplying remote stations.
So how do they do it? Well, the icebreakers use the momentum and power of the ship to push the bow up on to the ice. The ice is then pushed down by the weight of the ship. This causes the ice to break off in large chunks. The chunks are then pushed out of the way by the hull of the ship as it moves forward. Both of the Polar Class Icebreakers are capable of breaking through 6 foot thick ice at a continuous speed of 3 knots.. Not to be outdone, the Soviets have a nuclear powered icebreaker that goes by the name of YAMAL. She and her sister ships are the most powerful icebreakers in the world, capable of breaking 7 feet of ice at 3 knots.
The Coast Guard also operates icebreakers that are used in inland waterways such as the Great Lakes and Saint Lawrence Seaway. These ships are smaller in nature since the ice formed on these bodies of water is not as thick as those experienced in Arctic conditions. They operate under the same principals as the Polar Class ships and are mainly used to keep shipping lanes open during the winter.
Source: www.uscg.mil
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