Helicopter manufacturer Sikorsky has grounded all S92 aircraft worldwide for safety checks following an incident on a North Sea platform.
(Image credit Ardrossan Coast Guard)
Operators have been instructed to carry out the checks immediately.
They centre around the tail rotors and are expected to take several hours per aircraft.
The Air Accidents Investigation Branch (AAIB) is investigating an incident on the West Franklin Platform which happened last month.
An S92 experienced a technical fault when it was coming in to land. It left "significant gouge marks" on the deck of the platform.
Sikorsky issued the safety checks instruction overnight.
A Sikorsky spokeswoman said: "Safety is our top priority, and Sikorsky is working closely with our customer and investigative authorities.
"We are committed to keeping our customers informed. We will further communicate findings if the investigation reveals any safety or airworthiness issues that affect the S92 helicopter fleet."
Flights are expected to be disrupted for the rest of the day.
The Maritime and Coastguard Agency (MCA) said its S92s, operated by Bristow, would return to service throughout the day.
An MCA spokesman said: "The Inverness-based helicopter has already been brought back into service for lifesaving work and we are negotiating a limited return to service at other bases in the same manner."
The organisation Step Change in Safety, which works to improve safety in the UK oil industry, said it was in "close communication" with the relevant parties.
The group's executive director Les Linklater said: "The decision made by Sikorsky is a precautionary measure to ensure continued safe flight operations.
"Currently the duration of the inspections is expected to take up to 11 man-hours, which means this will cause some short-term delays.
"We are in close communication with trades unions, helicopter operators and the Civil Aviation Authority."