Airworthiness Directives; Airbus Helicopters Deutschland GmbH Helicopters

The FAA is adopting a new airworthiness directive (AD) for all Airbus Helicopters Deutschland GmbH Model MBB-BK 117 C-2 helicopters. The FAA previously sent this AD as an emergency AD to all known U.S. owners and operators of these helicopters. This AD was prompted by a report of vibrations of the yaw axis during a hover taxi. This AD requires repetitively inspecting the bolted joint between the cardan- pivot joint assembly and the tail rotor actuator piston rod and, depending on the results, taking corrective action. This AD also prohibits installing certain tail rotor actuators unless its requirements are met. These actions are specified in a European Union Aviation Safety Agency (EASA) AD, which is incorporated by reference. The FAA is issuing this AD to address the unsafe condition on these products.