Airbus Helicopters have issued new directives to operators aimed at ensuring more rigorous checks of gearboxes on three models of helicopter across its Dolphin fleet.
This is an additional safety precaution, built upon the lessons learnt from the 2016 225 accident in Norway.
The order covers helicopters within Airbus Helicopters’ Dolphin model – the SA365, AS365 and H155. The directive will become effective on 16 June.
While there have been no accidents due to main gearbox failure on the Dolphin fleet, the checks have been ordered as a proactive measure based on findings from the investigation into the accident in April 2016 involving a Super Puma 225 helicopter.
As part of its own investigation into the 29 April 2016 accident in Norway, Airbus Helicopters reviewed its entire fleet of helicopters and found that there was scope for the implementation of additional precautionary safety measures on the SA365, AS365 and H155.
EASA, Europe’s aviation watchdog has issued a corresponding airworthiness directive stating that investigations had shown that a particular type of planet gear was more susceptible to cracking than others. This planet gear type has now been permanently removed from service.
Operators will now have to carry out much more regular inspections of the magnetic plugs in the main gearbox and some will have to replace entire planet gear assembles.
Industry analysts expect that other OEMs will now be under pressure from customers to apply the additional precautions to their own products.