Airworthiness Directive · Amendment 39-9040 · The Boeing Company Airplanes
The Boeing Company Airplanes
This AD applies to The Boeing Company 747-400 Series, 747-400D Series, 747-400F Series.
The models as the FAA's AD index lists them. The serial ranges, installed parts and exceptions are in the AD itself: read it at the FAA.
This amendment adopts a new airworthiness directive (AD), applicable to certain Boeing Model 747-400 series airplanes, that requires replacement of the thrust reverser flow restrictor devices with one-way (check) valve restrictors. This amendment is prompted by reports of actuator piston seal leakage found during actuator overhaul on certain Model 747-400 series airplanes. The actions specified by this AD are intended to prevent possible deployment of a thrust reverser in flight and subsequent reduced controllability of the airplane.
