Summary
We propose to adopt a new airworthiness directive (AD) for certain Pratt & Whitney Division (PW) PW4000-94 inch and PW4000-100 inch model turbofan engines. This proposed AD was prompted by a report of a crack find in the high-pressure compressor (HPC) disk. This proposed AD would require performing an ultrasonic inspection (USI) or an eddy current inspection (ECI) of the HPC 10th stage disk. We are proposing this AD to prevent failure of the HPC 10th stage disk, an uncontained disk release, damage to the engine, and damage to the airplane.