Airworthiness Directives; Airbus Helicopters

The FAA is superseding Airworthiness Directive (AD) 2021-04- 21, which applies to certain Airbus Helicopters Model EC120B helicopters. AD 2021-04-21 required an inspection of the attachment bolts of the main rotor (MR) hub scissors assembly for discrepancies and repair if necessary; part marking of the attachment bolts of the MR hub scissors assembly; and repetitive inspections of the part marking of the attachment bolts, and repair if necessary. This AD continues to require the actions in AD 2021-04-21; and also requires part marking of the washer, scissor branch, and mast ring of the corresponding nut side, and repetitive inspections of the additional part markings and repair if necessary; as specified in a European Union Aviation Safety Agency (EASA) AD, which is incorporated by reference. This AD was prompted by a report of broken and bent attachment bolts of the MR hub scissors assembly and a determination that additional part markings of the washer, scissor branch, and mast ring of the corresponding nut side, and repetitive inspections of those part markings, are necessary to detect any rotation. The FAA is issuing this AD to address the unsafe condition on these products.