Airworthiness Directives; Robinson Helicopter Company (RHC) Model R44 Helicopters

This document publishes in the Federal Register an amendment adopting Airworthiness Directive (AD) 98-22-16 which was sent previously to all known U.S. owners and operators of RHC Model R44 helicopters by individual letters. This amendment supersedes AD 98-12- 19, issued August 5, 1998, applicable to RHC Model R44 helicopters, that currently requires main rotor blade inspections and replacement if a crack is found. This amendment requires the same inspections as AD 98-12-19, but mandates replacement of all the affected main rotor blades prior to further flight after November 15, 1998. This amendment is prompted by an incident in which a crack was discovered in a main rotor blade. The actions specified by this AD are intended to prevent failure of a main rotor blade and subsequent loss of control of the helicopter.