Airbus Helicopters has received a boost in its quest to get Super Puma-family helicopters back into the air again, with the US Federal Aviation Administration granting approval for a return to flight.
Via an alternative means of compliance (AMOC) notice, the FAA has adopted a number of measures contained in an emergency airworthiness directive (EAD) issued by European regulators in early October, designed to detect the warning signs of an imminent main gearbox failure.
Norwegian investigators have blamed the disintegration of a second-stage planet gear in the epicyclic module for the 29 April fatal crash of an H225 on the country’s west coast, but have yet to pinpoint the root cause of the issue.
The European Aviation Safety Agency grounded H225s and AS332 L2s following an accident investigation update in June, but released the helicopters to fly again on 7 October provided its safety measures are adopted.
These include replacement of a specific type of second-stage planet gear, replacement of the same component if it has been involved in an unusual event such as lightning strike or has reached a certain number of hours, and inspections of the oil filters and magnetic chip detectors after every 10h of flight.
“We will follow this in the coming months with an airworthiness directive, but the AMOC provides the approval to accomplish what needs to be done,” says the FAA.
Although covering only five helicopters on the US register, Airbus Helicopters sees the permission as an important step in the type’s rehabilitation.
However, flight bans remain in place in Norway and the UK, and there is still some work to do to convince customers of the Super Puma’s safety.
For example, Norwegian oil company Statoil confirms that it will no longer allow its workers to be transported in H225s or AS332 L2s for crew change or search and rescue (SAR) requirements, instead specifying the Sikorsky S-92 in contracts with operators CHC Helicopter and Bristow.
“We have no plans to start flying the H225, even if there should be a decision to lift the suspension by the Norwegian authorities,” it says.
However, Statoil still has a pair of AS332 L1s for SAR operations, as the variant was not covered by the grounding order.
CHC Helicopter – which operated the H225 involved in the April crash – is also yet to be convinced that it should return the type to service.
Although it has divested the majority of its Super Pumas via its Chapter 11 restructuring, it retains a fleet of six H225s and 16 AS332 L/L1/L2 models, according to its latest quarterly financial filing for the period ended 31 October.
CHC says: “Whilst the latest EAD permits a return to commercial operations, there remain technical issues on which CHC requires further detail to inform our safety case for any return to service.”
The operator does not provide further detail and, in a recent contract announcement, it pointedly refers to the S-92’s “proven safety and availability record”.