Airworthiness Directives; Airbus Helicopters Deutschland GmbH Helicopters

The FAA is adopting a new airworthiness directive (AD) for all Airbus Helicopters Deutschland GmbH (AHD) Model EC135P1, EC135P2, EC135P2+, EC135P3, EC135T1, EC135T2, EC135T2+, EC635T2+, and EC135T3 helicopters. This AD was prompted by reports of ruptured and deformed flexible couplings. This AD requires inspecting the axial displacement of the tail rotor drive shaft and, depending on the results, taking corrective actions including inspecting the flexible couplings. This AD also prohibits installing a tail rotor drive shaft unless certain procedures are followed. The FAA is issuing this AD to address the unsafe condition on these products.