Airworthiness Directives; CFM International CFM56-5 and -5B Series Turbofan Engines

This amendment adopts a new airworthiness directive (AD), that is applicable to CFM International CFM56-5 and -5B series turbofan engines. This amendment requires the establishment of an exhaust gas temperature (EGT) baseline and trend monitoring using the System for Analysis of Gas Turbine Engines (SAGE), or equivalent, as an option to EGT harness replacement, and if necessary, replacement of certain EGT harnesses and EGT couplings as soon as a slow and continuous EGT drift downward is noticed after the effective date of this AD. This amendment is prompted by reports of erroneous EGT readings. The actions specified by this AD are intended to prevent unexpected deterioration of critical rotating engine parts due to higher than desired engine operating EGT's.