Norway's Statoil (STO) said on Tuesday it expected to gradually resume flights of Sikorsky S-92 helicopters it uses to transport offshore workers, after all flights were stopped earlier in the day for safety checks.
The Sikorsky Aircraft Corp, which manufactures the helicopters, issued a service notice on Tuesday, saying the tail rotor and bearing assemblies of the S-92 should be checked following an incident in Scotland last December.
Sikorsky is a unit of Lockheed Martin Corp.
"We are starting to resume flights gradually this afternoon as helicopters are checked and put back in flight," Statoil's spokesman said.
The decision to stop the flights meant Statoil's workers were left stranded on oil platforms as the S-92 is the only model used by the company to transport people offshore Norway.
Statoil stopped using H225 Super Puma (PUMF.EX)
helicopters, a workhorse of the offshore oil industry
, following a fatal crash last April.
Sikorsky said the inspections could take about 11 hours, but the time depended on each operator.
"We have already been informed that many operators have already completed these inspections, and we anticipate the majority of the fleet will have the initial inspection accomplished within the next 24-48 hours," a spokesman said in an email.
In Britain, where S-92 flights were also stopped, the oil and gas industry lobby group said the inspections would create some "short-term disruption to operations" in the North Sea.
One of Britain's offshore operators, Shell, said it was working on alternative flight provision.
Sikorsky said in a separate note it was working closely with customers to determine the root cause of a problem with the tail rotor during a landing on a rig off Scotland on Dec. 28.
A spokesman for Britain's Air Accidents Investigation Branch said the authority was still investigating the incident near Aberdeen.
Both Statoil and Shell said their offshore production wasn't affected by the suspension of flights.
(Reporting by Nerijus Adomaitis and Karolin Schaps; Editing by Stine Jacobsen and Mark Potter)