Engine Trouble, Flooding Plague Polar Star
Despite incidents involving engine failure and flooding, the crew of U.S. Coast Guard Cutter Polar Star completed their mission on Tuesday, cutting a resupply channel through 15 miles of Antarctic ice in the Ross Sea and escorting supply vessels to the continent.
The Polar Star sailed from Seattle to assist in the annual delivery of operating supplies and fuel for National Science Foundation research stations in Antarctica during Operation Deep Freeze.
“Although we had less ice this year than last year, we had several engineering challenges to overcome to get to the point where we could position ourselves to moor in McMurdo,” said Captain Michael Davanzo, the commanding officer of the Polar Star. On January 16, Polar Star’s shaft seal failed causing flooding in the cutter’s engine room at a rate of approximately 20-gallons per minute. The crew responded quickly, using an emergency shaft seal to stop the flow of freezing, Antarctic water into the vessel. The crew was able dewater the engineering space and effect more permanent repairs to the seal to ensure the watertight integrity of the vessel.
Prior to that, on January 11, the vessel's progress was slowed after the one of her three main gas turbines failed. The crew uses the cutter’s main gas turbine power to breakup thick multi-year ice using her propellers. The crew found a programming issue between the engine and the cutter’s 1970s-era electrical system.
“If the Polar Star were to suffer a catastrophic mechanical failure, the nation would not be able to support heavy icebreaker missions like Operation Deep Freeze, and our nation has no vessel capable of rescuing the crew if the icebreakers were to fail in the ice,” said Vice Adm. Fred Midgette, commander, U.S. Coast Guard Pacific Area in Alameda, California. “The crewmembers aboard Polar Star not only accomplished their mission, but they did so despite extreme weather and numerous engineering challenges. This is a testament to their dedication and devotion to duty.” The 399-foot cutter r is expected to return to the U.S. in March 2018.
Polar Star is the only operational heavy icebreaker in the U.S. fleet. She was commissioned in 1976, weighs 13,500 tons and uses 75,000 horsepower to break ice up to 21 feet thick. The Coast Guard also operates one medium icebreaker, the 11,000-ton Healy. Commissioned in 1999, Healy can break ice up to 10 feet thick.
Polar Star's sister ship Polar Sea, also commissioned in 1976, left service since 2010 due to repeated failure of her main diesel engines. Last year, the Coast Guard determined it would be too costly to refurbish her even though her hull was sound, instead designating her has a parts donor to Polar Star. Instead, the Coast Guard has plans to build three heavy and three medium medium icebreakers, as part of plans to replace both vessels. The first newbuild is expected to be delivered in 2023.
Russia has nearly 40 icebreaker ships in service, with five more under construction and six more planned. Finland has seven, and Canada and Sweden each have six.