Airworthiness Directives; CFM International (CFMI) CFM56-5C Series Turbofan Engines

This amendment revises an existing airworthiness directive (AD) that is applicable to CFMI CFM56-5C series turbofan engines. That AD currently establishes new life limits for certain low pressure turbine rotor (LPTR) stage 3 disks and certain high pressure turbine rotor (HPTR) disks. This action removes the LPTR stage 3 disks and the HPTR disks from the parts listed with lowered life limits in the existing AD. This amendment is prompted by the results of an extensive life management program completed by the manufacturer, which no longer requires lower life limits for the LPTR stage 3 disks and HPTR disks listed in the existing AD. The actions specified in this AD are intended to prevent low-cycle-fatigue (LCF) failure of certain HPTR front shafts, HPTR front air seals, and booster spools, which could result in an uncontained engine failure and damage to the airplane.