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

الملخص

This document proposes the adoption of a new airworthiness directive (AD) for Bell Helicopter Textron, Inc. (BHTI) Model 205A, 205A-1, 205B, 212, 412, 412EP, and 412CF helicopters. The AD would require inspecting each affected tail rotor blade forward tip weight retention block (tip block) and the aft tip closure (tip closure) for adhesive bond voids and removing any tail rotor blade with an excessive void from service. The AD would also require modifying certain tail rotor blades by installing shear pins and tip closure rivets. This proposal is prompted by five occurrences of missing tip blocks or tip closures resulting in minor to substantial damage. The actions specified by the proposed AD are intended to prevent loss of a tip block or tip closure, loss of a tail rotor blade, and subsequent loss of control of the helicopter.