More than a hundred offshore workers were delayed from returning home after North Sea helicopter flights were cancelled amid safety fears.
All flights on Sikorsky S-92s were halted and recalled by the three main North Sea helicopter operators after the manufacturer issued an Air Safety Bulletin (ASB) following an incident offshore last month.
Search and Rescue (SAR) flights have also been impacted by the recall.
Around 30 helicopters used in North Sea operations were recalled for urgent checks by engineers after the ASB (Air Safety Bulletin) was published late on Monday evening.
It meant all flights to and from platforms were put on hold while operators Bristow, CHC and Babcocks worked around the clock to complete the safety checks.
Last night, the Offshore Helicopter Safety Leadership Group (OHSLG) said all checks were expected to be complete by noon today and the helicopters would start a phased return to service.
The shut down comes after the Sikorsky became the main helicopter for transporting workers offshore since its rival type, the Super Puma, was grounded in the wake of a fatal accident last year.
A Super Puma 225 helicopter plunged into the Norwegian North Sea killing all 13 on board including Laurencekirk father-of-two Iain Stuart leading to a ban on flights across Europe.
Last night the Offshore Helicopter Safety Leadership Group (OHSLG) insisted the decision to recall helicopters while maintenance checks were completed was not a grounding.
On social media workers spoke of concern about when they would be able to return home.
The call to stop flights of the Sikorskys, which are made by the helicopter business of US aerospace giant Lockheed Martin, came after a shuttle flight between Total’s Elgin platform and the West Franklin platform got into technical difficulties.
The incident is currently under investigation by the Air Accident Investigation Branch (AAIB).
In a statement the OHSLG, which is an amalgamation of the CAA’s Offshore Helicopter Safety Action Group (OHSAG) and Step Change in Safety’s Helicopter Safety Steering Group (HSSG), said safety was the main priority for the sector.
A spokeswoman said: “The operators will have completed the checks on all the aircraft by midday on Wednesday, January 11. It is expected that during the next 24 hours there will be a phased return of aircraft following full return to service testing.
“Clearly the priority is to ensure that both passengers and crew are safe and it is important to maintain a precautionary stance in what is an on-going investigation.
“As we receive information we will deliver it to our members, clients and the workforce.”
The bulletin issued yesterday was centred around the tail rotor and bearing assemblies.
Further checks are also being carried out on the Health and Usage Monitoring System (HUMS) which detect early indications of any failures.
The S-92 helicopters must have the checks carried out before they can take to the skies again.
The Civil Aviation Authority (CAA) yesterday stressed the decision was purely a manufacturer’s recall, not a regulatory decision.
It added that it was working closely with all the operators.
A spokeswoman for Sikorsky said: “Safety is our top priority, and Sikorsky is working closely with our customer and investigative authorities to determine the root cause of the loss of tail rotor authority in the Dec. 28 installation landing.
“Although the investigation into the December 28th incident has not been completed, Sikorsky released an Alert Service Bulletin on January 10th to define additional interim inspection requirements for the S-92 Tail Rotor Pitch Change Shaft.
“Those procedures include an off-aircraft check of the PCS bearing and that check must be done before next flight with some leeway for getting back to base.
“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 S-92 helicopter fleet.”
The Maritime and Coastguard Agency (MCA) said its S92s, operated by Bristow, would be returning to service once the checks had been completed.
The regional organiser for the RMT, Jake Molloy, said workers would support the decision by the manufacturer.
He said: “It means the aircraft has to be on the ground for some hours but I’m quite sure every worker in the North Sea would rather that rod and that bearing were inspected to ensure we don’t have a repeat of December 28th.”
Aberdeen South MP Callum McCaig said: “Safety must be the top priority in the oil and gas industry, and it is right that Sikorsky carries out checks on all S92 aircrafts following the incident on the West Franklin platform on December 28th.
“I hope Sikorsky are working closely with operators and services to ensure all workers offshore are fully aware of the timescale of these checks and if they may be affected getting on and offshore.
“Once all checks are carried out there must be total clarity on the functionality of these helicopters, and what has been discovered to explain the unsettling incident on the West Franklin platform.”