Airworthiness Directives; General Electric Company Engines

The FAA is adopting a new airworthiness directive (AD) for certain General Electric Company (GE) Model GE90-90B, GE90-94B, GE90- 110B1, and GE90-115B engines. This AD was prompted by a manufacturer investigation that revealed certain high-pressure turbine (HPT) stage 1 and HPT stage 2 disks were manufactured from powder metal material suspected to contain iron inclusion. This AD requires replacement of affected HPT stage 1 and HPT stage 2 disks with parts eligible for installation. The FAA is issuing this AD to address the unsafe condition on these products.