The European Aviation Safety Agency issued an emergency airworthiness directive (AD) on June 2 to ground the fleet of Airbus Helicopters AS332 L2 Super Puma and EC225 LP (H225) models, after more evidence of a potential unsafe condition in the main rotor assembly was discovered. This follows an April 29 crash of an EC225 LP near Bergen, Norway.
Feedback received after an AD requiring inspections revealed issues with the suspension bars, which are also known as lift struts. Some tightening torque values on the attachment bolts of the fittings were found to be out of tolerance. Some washers were incorrectly positioned in the fitting assemblies. Those components are involved in scheduled maintenance, Airbus confirmed.
According to EASA, the latest report from the Accident Investigation Board Norway (AIBN), “indicated metallurgical findings of fatigue and surface degradation in the outer race of a second stage planet gear of the main gearbox epicyclic module.” However, the agency pointed out that it cannot yet be determined whether this was “a contributing causal factor or subsequent failure from another initiating factor.”
The EASA-mandated grounding does not extend to search-and-rescue (SAR) operations. Norway and the UK aviation authorities, however, have issued directives that also ground the types for search and rescue missions.
In a written statement, Airbus commented: "In light of the new findings from the AIBN's preliminary investigation report, Airbus Helicopters supports EASA's cautious approach. We continue to fully support EASA, our customers and the ongoing investigation by providing information in full transparency, while working with the wider industry to ensure safety."