Airworthiness Directives; General Electric Company CF6-45 and CF6-50 Series Turbofan Engines

The FAA is adopting a new airworthiness directive (AD) for General Electric Company (GE) CF6-45 and CF6-50 series turbofan engines with certain low-pressure turbine (LPT) stage 3 disks installed. This AD requires fluorescent penetrant inspection (FPI) of the LPT stage 3 disk under certain conditions and removal of the disk from service before further flight if found cracked. This AD also requires initial and repetitive borescope inspections of the high-pressure turbine (HPT) rotor stage 1 and stage 2 blades for wear and damage, including excessive airfoil material loss. This AD results from three reports of uncontained failures of LPT stage 3 disks and eight reports of cracked LPT stage 3 disks found during shop visit inspections. We are issuing this AD to prevent critical life-limited rotating engine part failure, which could result in an uncontained engine failure and damage to the airplane.