Helicopters grounded after an aircraft ditched in the North Sea will not return to the air until March at the earliest, it emerged yesterday.
Manufacturer Eurocopter has been carrying out tests on the gearboxes used in Super Pumas after two of the helicopters ditched last year, but previously said it hoped the fleet would be flying again by next month.
Since the latest ditching on October 22, dozens of Super Pumas have been grounded in the UK, with only a limited number returning to service.
Eurocopter believes the incident involving a CHC-owned EC225 in October was almost identical to one involving a Bond helicopter in May.
The French firm said yesterday it had identified a “most probable root cause” for cracks found on the gearboxes of both aircraft, but did not go into detail about what the potential cause was.
It said it would carry out further tests later this month focused on its new theory, but did not expect the results to be available until late February.
It is understood it is now unlikely that the rest of the EC225 fleet will return to service before March.
An initial bulletin from the Air Accident Investigation Branch (AAIB) on the October incident reported that a crack in the main gear shaft had been discovered after the helicopter carried out a controlled ditching.
A warning light indicated a failure of the main gearbox lubrication system and triggered the crew’s response.
The initial testing confirmed that the warning light was actually set off in error – as happened with the ditching of the Bond helicopter in May.
In both incidents, all passengers and crew managed to escape into liferafts before being picked up.
Earlier this month, the boss of industry body Oil & Gas UK said he did not expect offshore helicopter operations to return to normal until late April or early May. He added that although there had been virtually no disruption for people operating in the southern and northern North Sea or west of Shetland, the main impact of the grounded helicopters had been felt in the central North Sea.