Summary
The FAA proposes to adopt a new airworthiness directive (AD) for all General Electric Company (GE) CF6-80C2A1, CF6-80C2A2, CF6- 80C2A3, CF6-80C2A5, CF6-80C2A5F, CF6-80C2A8, CF6-80C2B1, CF6-80C2B1F, CF6-80C2B2, CF6-80C2B2F, CF6-80C2B4, CF6-80C2B4F, CF6-80C2B5F, CF6- 80C2B6, CF6-80C2B6F, CF6-80C2B6FA, CF6-80C2B7F, CF6-80C2B8F, and CF6- 80C2D1F model turbofan engines. This proposed AD was prompted by reports of incidents that resulted in a significant fuel loss during flight and an in-flight shutdown (IFSD) of the engine. This proposed AD would require initial and repetitive shim checks of the hydromechanical unit/main engine control (HMU/MEC) idler adapter on the accessory gearbox (AGB) assembly and, depending on the results of the shim check, possible replacement of the inserts on the HMU/MEC idler adapter. As a terminating action to the repetitive shim checks, this proposed AD would also require a protrusion check and a pull-out test and replacements of inserts on the HMU/MECidler adapter that fail either test. The FAA is proposing this AD to address the unsafe condition on these products.