Airworthiness Directive · Amendment 39-15942 · Engine
Boeing Model 747-400 and -400F Series Airplanes Powered by Rolls-Royce RB211 Series Engines
This AD applies to Boeing Model 747-400 and -400F series airplanes, certificated in any category; Powered by Rolls-Royce RB211 series engines.
We are adopting a new airworthiness directive (AD) for certain Boeing Model 747-400 and -400F series airplanes. This AD requires modifying certain thrust reverser control system wiring to the flap control unit (FCU). This AD results from a report of automatic retraction of the leading edge flaps during takeoff due to indications transmitted to the FCU from the thrust reverser control system. We are issuing this AD to prevent automatic retraction of the leading edge flaps during takeoff, which could result in reduced climb performance and consequent collision with terrain and obstacles or forced landing of the airplane.
You are responsible for having the actions required by this AD performed within the compliance times specified, unless the actions have already been done.
Within 60 days after the effective date of this AD: Modify the thrust reverser control system wiring to the FCU in the P414 and P415 panels in accordance with the Accomplishment Instructions of Boeing Alert Service Bulletin 747-78A2181, dated June 8, 2009.
