AD 2012-13-02
Effective 08/23/2012 · Published 07/19/2012
Airworthiness Directives; Pratt & Whitney Turbofan Engines
Summary
We are superseding an existing airworthiness directive (AD) for all Pratt & Whitney Division PW4074 and PW4077 turbofan engines. That AD currently requires removing the 15th stage high-pressure compressor (HPC) disk within 12,000 cycles since new (CSN) or using a drawdown removal plan for disks that exceed 12,000 CSN. This new AD requires the same actions and clarifies that 15th stage HPC disks that have accumulated…