Airworthiness Directives; General Electric Company Turbofan Engines

We are adopting a new airworthiness directive (AD) for certain General Electric Company (GE) GEnx-1B54, -1B58, -1B64, -1B67, -1B70, - 1B54/P1, -1B58/P1, -1B64/P1, -1B67/ P1, -1B70/P1, -1B54/P2, -1B58/P2, -1B64/P2, -1B67/P2, -1B70/P2, -1B70C/ P1, -1B70/72/P1, -1B70/75/P1, -1B74/75/P1, -1B75/P1, -1B70C/P2, -1B70/ 72/P2, -1B70/75/P2, -1B74/75/P2, -1B75/P2, -1B76/P2, -1B76A/P2, -1B78/ P2, -2B67, -2B67B, and -2B67/P turbofan engines. This AD requires removal of affected high-pressure turbine (HPT) stator cases (HPT cases) from service and their replacement with a part eligible for installation. This AD was prompted by the discovery of a quality escape at a manufacturing facility. We are issuing this AD to address the unsafe condition on these products.