Action
Notice of proposed rulemaking (NPRM).
Summary
We propose to adopt a new airworthiness directive (AD) for all PW JT9D-7R4H1 turbofan engines. This proposed AD would require removing certain high-pressure compressor (HPC) shafts before their certified life limits, and establishes a new, lower life-limit for these parts. This proposed AD was prompted by reports of cracks in five HPC shafts. We are proposing this AD to correct the unsafe condition on these products.