Airworthiness Directives; Bell Textron Inc. Helicopters

The FAA is adopting a new airworthiness directive (AD) for all Bell Textron Inc. (Bell) Model 204B, 205A, 205A-1, 205B, and 210 helicopters. This AD was prompted by an accident and incidents involving failure of the tail boom attachment structure. This AD requires inspecting the tail boom assembly hardware, replacing tail boom attachment hardware, greasing the bolt shanks, and inspecting torque. This AD also prohibits installing steel alloy nuts on any helicopter. The FAA is issuing this AD to address the unsafe condition on these products.