Продолжаются работы про ремонту центрального винта крупнейшего ледокола Канады. Работы проводятся с 27 сентября непосредственно в море, близ селения Кеймбридж-Бей южном побережье острова Виктория.
Помимо команды на борту находился научный состав (100 человек) экcпедиции по определению границ Канадского континентального шельфа, перевезенный вертолетом на берег 29 сентября.
По окончанию ремонтных работ планируется вернуть Louis S. St. Laurent к операциям в восточной Арктике.
Canada’s flagship icebreaker marooned off Cambridge BayDivers now attempting to repair broken propellerJANE GEORGE
http://www.nunatsiaqonline.ca/stories/a ... ridge_bay/CAMBRIDGE BAY — A red and white icebreaker — a symbol of Canadian sovereignty in the Arctic — has been stuck in the same position in waters off Cambridge Bay since Sept. 27.
The vessel, a member of the “Heavy Arctic Icebreaker” fleet, is the largest vessel and the flagship of the Canadian Coast Guard’s icebreaker fleet.
But if the Louis St-Laurent was called upon right now to defend Arctic waters at the western end of the Northwest Passage or to assist a vessel in distress, the icebreaker’s crew would have to rely on their wits — not their mobility — to respond.
That’s because the 111.5-metre ship can’t move well, with only two of its three propellers working.
A propeller nut on the middle propellor of three “backed off approximately six inches” on Sept. 19, Brian LeBlanc, regional fleet director for the Canadian Coast Guard in the Arctic, said in an email Oct. 8.
“The cause of this problem is being investigated by the Canadian Coast Guard,” LeBlanc said in the email, in which he emphasized there is no risk to the environment.
But the breakdown means the Louis St-Laurent has been stuck since Sept. 27 near Cambridge Bay, within sight of a popular seaside area for cabins known as Akulailgok or “gravel pit” in English.
Repairs are currently underway to fix the problem, but the pace will depend on the weather, LeBlanc said.
The repairs are likely to be tricky. The huge central propeller is fixed to a long shaft about 20 metres long. Each one of its bearings helps the icebreaker cope with ramming through thick ice.
Local residents say divers and others involved in the repair job will be lucky to get out before sea ice — already overdue — starts to move in.
The approximately 100 scientists and crew members on board were able to complete previously planned work on the continental shelf mission before the break-down, LeBlanc said. The scientists departed Cambridge Bay via air charter Sept. 29 during a scheduled crew change.
However, a blog from that survey posted on the Transport Canada website says the breakdown did stop scientists from gathering seismic information, which is important for Canada’s defense of its offshore boundaries under the United Nations Convention on the Law of the Sea.
“Three-quarters of the way through the voyage we also encountered difficulty with the ship’s centre shaft propeller, and that prevented us from doing further seismic work,” reads the Sept. 29 blog entry.
Under UNCLOS, Canada can claim offshore territory beyond the 200-nautical mile limited if seismic mapping can prove by 2013 that its seabed is actually an extension of the Canadian land base, the continental shelf.
For the moment, only about 48 crew members, along with divers and other repair workers from the Vancouver-based underwater maintenance experts, Subsea Solutions Alliance, are on board.
LeBlanc couldn’t say how much the propeller repairs are likely to cost.
After the repairs are completed, the Louis S. St-Laurent “will assume normal operations in the Eastern Arctic,” LeBlanc said.
At this time of year, this usually consists of escorting resupply vessels.
The Louis St-Laurent is supposed to leave the Eastern Arctic — at the other end of the Northwest Passage — on Nov. 15 for St. John’s, Newfoundland, its home port, LeBlanc said.
It’s not the first time this aging icebreaker’s propellers have broken. Last year, Louis St-Laurent had to stop for repairs on one of its propeller shaft bearings.
In 2000, the propellers were completely replaced.
“The cold reality is that it is not unheard of for the propellers and associated parts to simply break down because of the severe stress they are placed under,” said Rob Huebert, associate director of the Centre for Military and Strategic Studies at the University of Calgary, in an email comment. “An icebreaker is probably the only ship that needs to constantly go forward and backwards at high revs.”
That puts tremendous stress on the propellers, he said.
When you factor in that the propellers also directly hit the ice at times, “it is surprising that this does not happen more often,” he said.
The Louis St-Laurent, named after Canada’s 12th prime minister, was built in 1967.
Five huge diesel engines provide the power for three shafts and propellers and can produce up to 29,000 horsepower of power for breaking through thick ice.
The ship is due for decommissioning in 2017, when the new $750 million, 140-metre icebreaker, the John Diefenbaker, is expected to be delivered.