Airworthiness Directives; Turbomeca S.A. Artouste II and Artouste III Series Turboshaft Engines

This amendment adopts a new airworthiness directive (AD), that is applicable to Turbomeca S.A. Artouste II and Artouste III series turboshaft engines. This amendment requires installation of modification TU 24, TU 167, or TU 164, depending on the specific engine series. These modifications will prevent uncommanded partial closing or total closing of the electrical fuel cock, which will prevent uncommanded in-flight engine shutdown. From the effective date of this AD, and until the modification is installed, this amendment will also limit the duration of the engine operating cycle. This amendment is prompted by reports of unexpected power loss during test flights. The actions specified by this AD are intended to prevent unexpected power loss, which could result in an uncommanded in-flight engine shutdown, autorotation, and forced landing.