Action
Final rule; request for comments.
Summary
The FAA is superseding Airworthiness Directive (AD) 2019-03-04 for all Engine Alliance (EA) GP7270 and GP7277 model turbofan engines with a certain engine 1st-stage low-pressure compressor (LPC) rotor assembly, referred to after this as the "engine fan hub assembly," installed. AD 2019-03-04 required a visual inspection of the engine fan hub assembly for damage, a one-time eddy current inspection (ECI) of the fan hub blade slot bottom and blade slot front edge for cracks, and removal of parts if damage or defects are found. For certain GP7270 and GP7277 model turbofan engines, this AD continues to require a one-time ECI of the engine fan hub blade slot bottom and blade slot front edge for cracks and a visual inspection of the engine fan hub assembly for damage. For all GP7270 and GP7277 model turbofan engines, this AD also requires an independent inspection of the engine fan hub assembly prior to reassembly of the engine fan hub blade lock assembly. For certain serial-numbered GP7270 and GP7277 model turbofan engines, this AD requires replacement of the engine fan hub blade lock assembly. This AD was prompted by an uncontained failure of the engine fan hub. The FAA is issuing this AD to address the unsafe condition on these products.