EASA has issued an Emergency Airworthiness Directive 2016-0104-E which prohibits any flights of Airbus AS332L2 and EC225 helicopters with the exception of a single flight without passengers to ferry such a helicopter to a maintenance base.  This follows earlier groundings from the national Civil Aviation Authorities of Norway and the UK, with the exception of Search and Rescue flights.  These are now superceded by the EASA actions.  The latest national documents are the UK CAA Safety Directive SD-20167/003 and the Norwegian equivalent 16/05616-9.

This follows the ongoing investigation into the fatal accident of EC225 LN-OJF operated by CHC which suffered a fatal accident on 29th April on a flight from the Gullfaks rig to Bergen Airport in Norway.  An initial Emergency AD 2016-0089-E was issued requiring, as a precautionary measure, the accomplishment of one-time inspections.  Return data from operators accomplishing this AD revealed installation findings for the Main Gear Box (MGB) upper deck fittings of the three MGB suspension bars.

These findings prompted EASA to issue superseding AD 2016-0103-E for further inspection and replacement instructions for correct installation of the MGB suspension bars and attachment fittings.  Soon after AD 2016-0103-E was issued, an updated report from the Accident Investigation Board of Norway (AIBN) indicated metallurgical findings of fatigue and surface degradation in the outer race of a second stage planet gear of the MGB epi-cyclic module. EASA particularly note that it cannot yet be determined if this is a contributing factor or or the result of something other factor.  Photos of the parts can be seen in this AIBN report from 1st June.

On this basis EASA have decided to temporarily ground the fleet as an additional precautionary measure, pending further investigation to determine the root cause(s) of the reported damage.

HeliHub.com also draws your attention to the article – Who should we blame when an aircraft crashes?

Jeremy Parkin – HeliHub.com