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

Riepilogo

This document publishes in the Federal Register an amendment adopting Airworthiness Directive (AD) 2007-19-53, which was sent previously to all known U.S. owners and operators of the specified Bell Helicopter Textron, Inc. (BHTI) model helicopters by individual letters. This AD requires replacing each affected tail rotor blade (blade) with an airworthy blade with a serial number not listed in the applicability of this AD. This AD is prompted by three incidents in which blade tip weights were slung from the blades during flight causing significant vibration. The actions specified by this AD are intended to prevent loss of a blade tip weight, loss of a blade, and subsequent loss of control of the helicopter.