Airworthiness Directives; Boeing Model 777-200LR Series Airplanes Powered by General Electric (GE) Model GE90-110B Engines, and Model 777-300ER Series Airplanes Powered by GE Model GE90-115B Engines

摘要

We are revising an existing airworthiness directive (AD) that applies to certain Boeing Model 777-200LR and -300ER series airplanes. That AD currently requires revising the airplane flight manual to prohibit takeoffs at less than full-rated thrust. This new AD reduces the applicability of the existing AD. This AD results from a report of two occurrences of engine thrust rollback during takeoff. We are issuing this AD to prevent dual-engine thrust rollback during the takeoff phase of flight, which could result in the airplane failing to lift off before reaching the end of the runway or failing to clear obstacles below the takeoff flight path.