Action
Final rule.
Summary
The FAA is adopting a new airworthiness directive (AD) for all Airbus Helicopters Deutschland GmbH Model MBB-BK 117 A-1, MBB-BK 117 A- 3, MBB-BK 117 A-4, MBB-BK 117 B-1, MBB-BK 117 B-2, and MBB-BK 117 C-1 helicopters. This AD was prompted by a report of sudden severe vibrations and a cracked open blade trailing edge caused by a loosened lead inner weight. This AD requires inspections to determine if any bolted main rotor blades are installed, and replacement of the affected main rotor blades. The FAA is issuing this AD to address the unsafe condition on these products.