Summary
This amendment proposes the adoption of a new airworthiness directive (AD) that applies to GE CF6-50 turbofan engines. This proposal would require removal of old high pressure compressor (HPC) air ducts and mating hardware and replacement with newly designed air ducts and reworked mating hardware. This proposal is prompted by reports of an uncontained low pressure turbine (LPT) disk failure that resulted from an air duct failure that caused a fan mid shaft (FMS) separation. The actions specified by the proposed AD are intended to prevent HPC air duct failures that could result in FMS failures, that in turn could result in rejected takeoffs or uncontained LPT events.