LONDON — Oil and gas companies operating off the coast of the UK are temporarily refraining from flying the two models of Super Puma helicopter subject to the latest recommendation issued by the UK Air Accidents Investigation Branch (AAIB). UK Oil and Gas said this will apply to all passenger flights over the weekend.
The AAIB recommended that Eurocopter, with the European Aviation Safety Agency (EASA), develop and implement an inspection of the internal components of the main rotor gearbox epicyclic module for all AS332L2 and EC225LP model helicopters as a matter of urgency to ensure the continued airworthiness of the main rotor gearbox.
The AS332L2 was the model of Super Puma that crashed on April 1 killing all 16 people aboard. Twenty-five helicopters in the UK offshore fleet will be affected.
This inspection is in addition to an earlier EASA Emergency Airworthiness Directive, and the AAIB said it should be made mandatory with immediate effect by an additional EASA directive.
Representatives from the oil and gas companies together with helicopter operators Bond, Bristow and CHC Scotia will meet on Sunday afternoon to determine what further action needs to be taken in light of the implications of further details expected to emerge from the European Aviation Safety Agency over the weekend.
AAIB’s examination of the wreckage from the April 1 crash had identified that the accident occurred following a catastrophic failure of the main rotor gearbox within the epicyclic module, leading to main rotor detachment. The sequence of failure is now better understood, but further work is required to determine the initiating event.
The work continues as the final failure of the gearbox involved metal debris being shot through the meshing gears and bearings, absorbing energy from the engines and the rotor assembly, leading to the gearbox bursting. This has resulted in a large amount of secondary damage to all gearbox components, potentially masking the initial failure.