Airworthiness Directives; Airbus Helicopters Deutschland GmbH (AHD) Helicopters

The FAA is adopting a new airworthiness directive (AD) for all Airbus Helicopters Deutschland GmbH (AHD) Helicopters Model MBB-BK 117 D-3 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 a crack on the affected part, which was detected after the crew reported increased vibration of the helicopter. This AD requires inspecting the rotor hub-shaft for a crack and depending on the inspection results, replacing any rotor hub-shaft that has any cracks and reporting information after accomplishment of the replacement. This AD also prohibits installing any affected rotor hub- shaft on any helicopter, unless certain requirements are met. The FAA is issuing this AD to address the unsafe condition on these products.