Airworthiness Directives; Airbus Helicopters Deutschland GmbH (AHD) Helicopters
Key claim: The FAA proposes a new airworthiness directive requiring repetitive inspections and potential replacement of tail rotor blade assemblies on Airbus Helicopters Deutschland EC135/EC635 models due to intergranular corrosion-induced cracking.
Abstract
(Proposed Rule · Transportation Department, Federal Aviation Administration) The FAA proposes to adopt a new airworthiness directive (AD) for all Airbus Helicopters Deutschland GmbH (AHD) Model EC135P1, EC135P2, EC135P2+, EC135P3, EC135T1, EC135T2, EC135T2+, EC135T3, and EC635T2+ helicopters. This proposed AD was prompted by a report of a separated tail rotor blade (TRB) assembly due to a crack caused by intergranular corrosion. This proposed AD would require repetitively inspecting a certain TRB assembly for cracks and, depending on the results, removing any cracked TRB assembly from service and replacing an affected part as terminating action for the repetitive inspections. This proposed AD would also prohibit installing a certain TRB assembly on any helicopter unless certain requirements are met. The FAA is proposing this AD to address the unsafe condition on these products.
Why this matters
Tail rotor blade failures are a recognized catastrophic risk in helicopter operations, and repetitive inspection regimes are the FAA’s standard tool for managing corrosion-driven fatigue cracking until a permanent redesign or replacement schedule is available. The proposed AD continues an ongoing pattern of European-origin rotorcraft component ADs being adopted by the FAA to maintain airworthiness parity with EASA.