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Cracks found in rudders of BP tankers Both of company’s new Alaska double-hull tankers in Washington shipyard for repairs; one will be out of service for weeks The Associated Press
Two of BP’s new double-hull tankers that carry Alaska crude oil have developed mysterious cracks in their rudders.
“It’s disappointing,” said Anil Mathur, president of Alaska Tanker Co., BP’s shipping company in surburban Portland, Ore.
“But when you come up with brand new designs, you can have new problems. The important thing was, this was not a catastrophic failure. This is embryonic. The problem has been caught very, very early.”
Both tankers are docked at a shipyard in Port Angeles, Wash.
One of the ships, the Alaskan Frontier, is expected to be out of service for several weeks pending repairs to cracks in both its rudders.
The Alaskan Frontier was the first in a fleet of four new double-hull tankers that BP is building to carry North Slope crude oil from Valdez to West Coast refineries. It has been in service since August.
A second and newer ship, the Alaskan Explorer, is expected to be out of service through this week. It has smaller cracks in only one of its twin rudders, Mathur said.
The Alaskan Frontier has hauled about 25 loads of crude oil out of Alaska, while the Alaskan Explorer — which made an unusual public relations stop in Juneau in April — has carried only one load, Mathur said.
The BP ships are part of efforts by all three of the major oil companies operating in Alaska to create a new generation of spill-resistant tankers. The companies were obliged to build the ships after the disastrous Exxon Valdez oil spill in Prince William Sound in 1989. Congress required all oil tankers have double hulls by 2015. The hope is that if the outer hull ruptures, the inner hull would contain the oil. Ships built in San Diego National Steel and Shipbuilding Co. of San Diego, a subsidiary of General Dynamics, built the Alaskan Frontier and the Alaskan Explorer. The company now is building BP’s final two “Alaska Class” tankers, due for service by the middle of next year.
BP has promoted its new tankers as “the most environmentally friendly oil tankers ever built,” featuring not only double hulls but advanced navigation systems and twin engines, propellers and rudders that can power and control the ship in case one system fails. The ships cost $250 million each.
Each tanker can carry up to 1.3 million barrels of crude oil, or more than one day’s North Slope oil production.
The steel rudders, like everything about the 941-foot tankers, are jumbo-size, measuring about 30 feet high and 18 feet wide. They’re mounted behind enormous propellers and provide the means of steering the ship through the sometimes rough North Pacific Ocean.
Divers discovered the rudder cracks during a scheduled inspection of the Alaskan Frontier the week of May 9, Mathur said. The inspection turned up several cracks in its rudders, the largest measuring 9 feet long.
A subsequent check of the newer sister ship, the Alaskan Explorer, showed three cracks on one of its rudders, the longest about 15 inches.
The Alaskan Explorer is expected to return to service by week’s end, once the cracks are repaired, Mathur said. As a precaution, he added, a tug will escort the empty ship when it enters Prince William Sound. Normally, only tankers loaded with oil and headed out of the sound get tug escorts.
Divers also will inspect the rudders on every voyage, he said. One ship will be out until July Fixing the Alaskan Frontier is a bigger challenge. Mostly likely, that ship will need to go to a shipyard with larger cranes in Vancouver, British Columbia. There, workers will tip the vessel to better expose the rudders. They’ll remove the rudders for repairs. The tanker likely will be out of service until July, Mathur said.
Alaska Tanker has eight ships, including the two new double-hull tankers, and the company plans to use two older ships that had been scheduled for retirement to avoid interrupting crude oil deliveries, he said.
The company has put together a team of shipbuilders, engineers and inspectors to try to determine what caused the cracks.
“It’s really important to understand how this happened, so that the fix takes care of the underlying cause,” Mathur said.
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