European Aviation Safety Agency (EASA) on Friday, October 7, 2016, decided to lift the temporary flight suspension of the Super Puma EC225 LP and AS332 L2 helicopters from Airbus Helicopters.
The Norwegian Civil Aviation Authority put in place the ban on all helicopters of the H225 and AS332L2 type, including search and rescue flights, in June following a fatal accident of an EC225 LP helicopter in Norway on April 29, 2016. The CHC-operated Super Puma crashed near Bergen while returning to land from a Statoil offshore platform.
To remind, after the crash, the Norwegian Civil Aviation Authority grounded all EC255 type helicopters, but the order did not apply to any search and rescue flights. Later in May, the aviation authority in Norway extended the no flight ban to include the AS332L2 Super Puma helicopter.
According to EASA, the set of ‘very stringent’ protective measures which enable the decision to allow these type of helicopters to return to flight include:
– The elimination of a specific type (Type A) of 2nd stage main gearbox planet gear involved in the accident by another type (Type B) which has a demonstrated reliable service life.
– An additional safety factor applied to the demonstrated service life of this gear type (Type B), resulting in the time before replacement being reduced to less than half its current value.
– The daily inspection or after 10 flight hours (whichever comes first) of the chip detectors, and every 10 flight hours oil filter with very stringent criteria.
The aviation safety agency said that all main gearboxes that have suffered from unusual events will be withdrawn from service. Unusual events include external events that might shock the gearbox but without visual evidence of damage.
EASA stated it has been closely monitoring the analysis and tests conducted by Airbus Helicopters.
“We maintain our full support to the investigation led by the Accident Investigation Bureau of Norway (AIBN) for the accident. This action continues to address the initial safety recommendation on EASA and we will address any further recommendations addressed to EASA,” the agency said.
EASA also noted it will closely monitor the compliance action taken by the helicopter manufacturer and operators following the return to service along with operational information.