Summary
The FAA proposes to adopt a new airworthiness directive (AD) for all Airbus Helicopters Deutschland GmbH Model MBB-BK 117 D-3 helicopters. This proposed AD was prompted by a report of excessive vibrations in-flight due to an incorrect installation of the angular ball bearing of the control ring assembly. This proposed AD would require a one-time inspection of the affected swashplates and, depending on the results of the inspection, corrective actions. This AD would prohibit the installation of an affected swashplate on a helicopter, unless certain requirements are met. The FAA is proposing this AD to address the unsafe condition on these products.