Airworthiness Directives; Pratt & Whitney JT8D-7, -7A, -7B, -9, -9A, -11, -15, -15A, -17, -17A, -17R, and -17AR Series Turbofan Engines

摘要

We are superseding an existing airworthiness directive (AD) for Pratt & Whitney (PW) JT8D-1, -1A, -1B, -7, -7A, -7B, -9, -9A, -11, -15, -15A, -17, -17A, -17R, and -17AR series turbofan engines. That AD currently requires revisions to the engine manufacturer's time limits section (TLS) to include enhanced inspection of selected critical life- limited parts at each piece-part opportunity. This AD modifies the TLS of the manufacturer's engine manual and an air carrier's approved continuous airworthiness maintenance program to incorporate additional inspection requirements and reduce the model applicability. This AD was prompted by PW developing, and the FAA approving, improved inspection procedures for the critical life-limited parts. The mandatory inspections are needed to identify those critical rotating parts with conditions which, if allowed to continue in service, could result in uncontained failures. 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.