Airworthiness Directives; Boeing Model 747 Airplanes

We are adopting a new airworthiness directive (AD) for certain Boeing Model 747 airplanes. This AD requires inspecting the trunnion fork assembly of the wing landing gears to determine the part number and serial number and to determine the category of the trunnion fork assemblies. For certain airplanes, this AD also requires, if necessary, various inspections to detect discrepancies of the trunnion fork assemblies, related investigative/corrective actions, and a terminating action. This AD results from a report of a fractured trunnion fork assembly. We are issuing this AD to prevent a fractured trunnion fork assembly, which could result in the collapse of a wing landing gear on the ground and possible damage to hydraulic equipment and the aileron and spoiler cables. Such damage could result in reduced controllability of the airplane.