After drifting toward shore on a floating drill rig tilted by 30-foot swells and 45-knot winds, then riding a basket up to a hovering Coast Guard helicopter, Todd Case said he would revise the towing plan for the vessel on a winter trip across the Gulf of Alaska.
In hindsight, he told a Coast Guard investigation panel Wednesday, two tugs would have been advisable for towing the Kulluk, a Royal Dutch Shell PLC drill vessel, on its December voyage from Dutch Harbor in the Aleutian Islands to Seattle.
“Multiple tugs would have kept us from having the incident we had,” he said.
On Dec. 27, the Kulluk lost its tow line to the single vessel towing it, the Aiviq, and four days later it ran aground off tiny Sitkalidak Island, just off Kodiak Island. All 18 people on board were rescued without injury. The drill vessel was refloated Jan. 6 but damage was a factor in Shell losing the 2013 Arctic Ocean drilling season.
Case was employed by Noble Drilling to be the offshore installation manager on the Kulluk, a 266-foot diameter drilling barge with a funnel-shape hull and a 160-foot derrick. Shell used the vessel for exploratory drilling in the Beaufort Sea during the short open water season and in December was moving it to a shipyard to prepare for 2013.
The Aiviq, a 360-foot anchor handler, was built to tow the Kulluk.
Case told the Coast Guard panel that he had ridden the Kulluk north behind the Aiviq through the Chukchi Sea six months earlier and watched it handle foul weather. He was confident it could handle the Gulf of Alaska in winter, he said.
The weather was not at bad at first.
“Christmas Day, we barbecued outside,” he said.
However, as wind and waves picked up, the pitch and roll regularly exceeded 6 degrees, the level when a procedures manual called for slowing down or stopping. The crew discussed moving farther out to sea to try to put the storm behind them.
“We were just starting to talk about this when all hell broke loose,” he said.
The line between the vessels parted. Within hours, the Aiviq had attached to the Kulluk’s emergency tow line, but plans for reaching Seattle changed.
“We were going to try to get into a safe haven,” he said, so repairs could be made to the main towing system.
That changed again early Dec. 28. Case was awakened and told the Aiviq’s four engines had lost power. Both vessels began drifting toward Kodiak Island.
A Coast Guard cutter and relief tugs reached the scene and tried to tow the Aiviq while its crew waited for engine parts. A shore-side Shell official ordered Case and his crew to abandon the barge, but when Coast Guard helicopters approached early on the night of Dec. 28, pilots reported the vessel’s helicopter pad, where a basket would be lowered, to be heaving 50 feet up and down. Pilots also worried the helicopters could have been blown into the derrick. The attempt was abandoned for the night.
Case said launching lifeboats was not a consideration. It was too dangerous to walk on the deck, he said, much less approach the rail, and a pod holding the 18-member crew could easily have been pushed beneath the funnel-shaped hull and crushed.
“I think it would have had a bad outcome,” he said.
The crew rode out the swells another night. Case ordered crew members to prepare to launch an anchor, and while the vessels were under tow to the tug Guardsman, the anchorage was mistakenly deployed, he said. He did not know for how long, he said, and the anchor was quickly retrieved.
A lull in the weather Dec. 29 allowed two Coast Guard helicopters to return and pull the Kulluk crew off in three shifts. Case was the second to last person to be hauled up.
On Jan. 31, the repaired Aiviq and the Alert, a tug on loan from escorting Prince William Sound oil tankers, were briefly able to make headway pulling the Kulluk southwest away from land. But when the line to the Aiviq broke again, and with the Kulluk pulling the Alert toward Kodiak, Shell officials ordered the tug to cut the barge loose.
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