Mystery cracks halt BP's new supertankers

Two of BP’s new double-hull tankers that carry Alaska crude oil have developed mysterious cracks in their rudders, the company said.

“When you come up with brand new designs, you can have new problems,” said Anil Mathur, president of Alaska Tanker Co, BP’s shipping company in suburban Portland, Oregon, USA.

“The important thing was, this was not a catastrophic failure. This is embryonic. The problem has been caught very, very early.”

The BP ships, which are docked at a shipyard in Port Angeles, Washington, are part of attempts by major oil companies operating in Alaska to create a new generation of spill-resistant tankers. The Alaskan Frontier and the Alaskan Explorer cost about €200m each.

Alaskan Frontier is expected to be out of service for several weeks pending repairs to cracks in both its rudders. The ship was the first in a fleet of four new double-hull tankers that London-based BP is building to carry North Slope crude oil from Valdez to West Coast refineries. It has been in service since August.

The Alaskan Explorer is expected to be out of service during 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 has carried only one load, he added.

Each of the existing BP tankers can carry up to 1.3 million barrels of crude oil, or more than one day’s North Slope oil production.

The companies were obliged to build the ships after the Exxon Valdez oil spill in Prince William Sound in 1989. Congress required oil tankers to have double hulls by 2015. The hope is that if the outer hull ruptures, the inner hull would contain the oil.

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.

National Steel and Shipbuilding of San Diego, a subsidiary of General Dynamics Corp, built the two ships. The company now is building BP’s final two “Alaska Class” tankers, due for service by the middle of next year.