Airworthiness Directive · Amendment 39-12276 · General Electric Company (GE) CF6-50 Turbofan Engines
General Electric Company (GE) CF6-50 Turbofan Engines
This airworthiness directive (AD) is applicable to General Electric Company (GE) CF6-50 turbofan engines with high pressure compressor (HPC) rotor air duct assemblies, part numbers (P/N's): 9128M36G03 / G04 / G05 / G06 / G08 / G20 / G21, or 1644M16G03 installed. This AD is also applicable to CF6-50 turbofan engines with HPC rear shaft P/N's: 1999M25P01 / P02 / P03 / P04 / P05 / P06 / or P07 installed. These engines are installed on but not limited to Boeing 747, Airbus A300, and McDonnell Douglas DC10 airplanes.
This amendment adopts a new airworthiness directive (AD) that is applicable to General Electric Company (GE) CF6-50 turbofan engines. This amendment requires removal of old high pressure compressor (HPC) air ducts and mating hardware and replacement with newly designed air ducts and reworked mating hardware. This amendment also requires the repetitive inspection of certain reworked mating hardware. This amendment 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 this 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, and to prevent HPC rear shaft failures that could result in uncontained engine failures.
