AD 2000-02-12 Amendment 39-11579

This document publishes in the Federal Register an amendment adopting Airworthiness Directive (AD) 2000-02-12, which was sent previously to all known U.S. owners and operators of Bell Helicopter Textron Canada (BHTC) Model 407 helicopters by individual letters. This AD requires inspecting engine oil cooler blower shaft bearings (bearings) for roughness at specified time intervals and replacing any rough bearings before further flight. This amendment is prompted by several bearing failures. The actions specified by this AD are intended to prevent bearing failure, loss of tail rotor drive, and a subsequent forced landing.