Summary
The FAA proposes to adopt a new airworthiness directive (AD) for all General Electric Company (GE) GEnx-1B64, GEnx-1B64/P1, GEnx- 1B64/P2, GEnx-1B67, GEnx-1B67/P1, GEnx-1B67/P2, GEnx-1B70, GEnx-1B70/ 75/P1, GEnx-1B70/75/P2, GEnx-1B70/P1, GEnx-1B70/P2, GEnx-1B70C/P1, GEnx-1B70C/P2, GEnx-1B74/75/P1, GEnx-1B74/75/P2, GEnx-1B76/P2, GEnx- 1B76A/P2, GEnx-2B67, GEnx-2B67/P, and GEnx-2B67B model turbofan engines. This proposed AD was prompted by an in-service occurrence of loss of engine thrust control resulting in uncommanded high thrust. This proposed AD would require revising the operator's existing FAA- approved minimum equipment list (MEL) by incorporating into the MEL the dispatch restrictions listed in this AD. This proposed AD would also require initial and repetitive replacement of the electronic engine control (EEC) MN4 microprocessor. The FAA is proposing this AD to address the unsafe condition on these products.