Summary
The FAA proposes to adopt a new airworthiness directive (AD) for certain Leonardo S.p.a. Model A109E helicopters. This proposed AD was prompted by reports that certain tail rotor gearbox assemblies were installed on Model A109E helicopters and those parts are not approved for installation on that helicopter model. Because those assemblies are not part of the type design for Model A109E helicopters, there are no overhaul or life limits included in the applicable maintenance manuals. This proposed AD would require replacement of each affected tail rotor gearbox assembly with a serviceable part, as specified in a European Union Aviation Safety Agency (EASA) AD, which is proposed for incorporation by reference (IBR). The FAA is proposing this AD to address the unsafe condition on these products.