Airworthiness Directives; Turbomeca Artouste III Series Turboshaft Engines

This amendment supersedes an existing airworthiness directive (AD), that is applicable to Turbomeca Artouste III series turboshaft engines with injection wheels part numbers (P/N's) 218.25.700.0, 218.25.704.0, 243.25.709.0, 243.25.713.0, 0.218.27.705.0, 0.218.27.709.0, and 0.218.27.713.0 installed. That AD currently requires smoke emission checks after every ground engine shutdown. If smoke is detected, that AD requires inspecting for fuel flow. If fuel flow is not detected, the engine may have injection wheel cracks, which requires removing the engine from service for repair. If fuel flow is detected, the engine may have a malfunctioning electric fuel cock, which requires removing the electric fuel cock from service and replacing with a serviceable part. This amendment has similar requirements as the original AD, except that the smoke emissions are to be checked after the last flight of the day, as opposed to after every flight, as required by the original AD. This amendment also requires inspection of central labyrinths not previously inspected or not replaced after the engine logged 1,500 operating hours, and, replacement of these labyrinths if necessary. This amendment is prompted by reports and analyses of in-flight shutdowns (IFSD's) occurring since the issuance of AD 2000-06-12. The actions specified by this AD are intended to prevent injection wheel cracks and excessive central labyrinth wear, which could result in an IFSD.