Airworthiness Directives; Pratt & Whitney JT9D Series Turbofan Engines

This amendment adopts a new airworthiness directive (AD), applicable to Pratt & Whitney JT9D series turbofan engines, that requires initial and repetitive eddy current inspections (ECI) of 14th and 15th stage high pressure compressor (HPC) disks for cracks, and removal of cracked disks and replacement with serviceable parts. This amendment is prompted by reports of disk bore cracks found during shop inspections on both the 14th and 15th stage HPC disks. The actions specified by this AD are intended to prevent 14th and 15th stage HPC disk rupture, which could result in an uncontained engine failure and damage to the aircraft.