Action
Notice of proposed rulemaking (NPRM).
Summary
The FAA proposes to adopt a new airworthiness directive (AD) for certain Pratt & Whitney Canada Corporation (P&WC) PW308A and PW308C model turbofan engines. This proposed AD was prompted by a manufacturer's design review which identified that the combustion chamber outer case (CCOC) to rear compressor case (RCC) flange bolt low cycle fatigue life was inadequate and that those flange bolts may develop cracks resulting in flange bolt fracture. This proposed AD would require replacing all CCOC flange bolts and modifying the CCOC and inner bypass ducts. This proposed AD would also prohibit installation of certain flange bolts on any affected engine, as specified in a Transport Canada AD, which is proposed for incorporation by reference (IBR). The FAA is proposing this AD to address the unsafe condition on these products.