The drill ship was being towed from Dutch Harbor in the Aleutian Islands to Seattle when problems arose Thursday. Responders said the rig lost its towline with the Aiviq, so the cutter Haley was sent there as a safety precaution. The Aiviq reported multiple engine failures after the cutter reached the stricken vessels early Friday.
Cutter crews tried to fix a tow line to the Aiviq to keep it from drifting, but that attempt failed when part of the towline got wrapped around one of the Haley's propellers. The cutter left after the Coast Guard sent a C-130 aircraft.
The Kulluk is one of two drill ships Shell operated this year in the short Arctic Ocean open water season. A round ship with a 160-foot derrick, it was designed for extended drilling in Arctic waters, and has an ice-reinforced, funnel-shape hull 266 feet in diameter. The conical shape is designed to deflect moving ice downward and break it into small pieces.
The Aiviq is owned and operated by Edison Chouest Offshore of Galliano, La.
Churchfield said an investigation will be conducted into the cause of problems.
He lauded the involved responders dealing with extremely challenging conditions. He also praised the performance of Shell and its contractors.
"Flawless operations is always the goal. But being a responsible operator also means putting contingency plans in place," Churchfield said. "Shell has done that throughout."
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