Airworthiness Directives; Bell Helicopter Textron, Inc. Model 204B, 205A, 205A-1, 205B, 210, 212, 412, 412CF, 412EP Helicopters

概要

We are publishing in the Federal Register an amendment which was sent previously to all known U.S. owners and operators that supersedes an existing airworthiness directive (AD) for the specified Bell Helicopter Textron, Inc. (BHT) Model helicopters with certain tail rotor blades (blades). The superseded AD requires, before further flight, replacing certain blades with airworthy blades. This AD retains the requirements of the superseded AD but adds new blade part numbers (P/Ns) and serial numbers (S/Ns) to the applicability. This AD was prompted by another incident in which the blade tip weight separated from a blade during flight, causing vibration. This incident led to the determination that additional blades could be affected, and should be added to the applicability. We are issuing this AD to prevent loss of the blade tip weight, loss of a blade, and subsequent loss of control of the helicopter.