Airworthiness Directives; Boeing Model 747-400 and -400D Series Airplanes

This amendment supersedes an existing airworthiness directive (AD), applicable to certain Boeing Model 747-400 series airplanes, that currently requires installation of strap assemblies on the ceiling panels and rails that support the video monitors. For certain airplanes, this amendment requires replacement of certain plate assemblies within the ceiling panel strap assemblies with new, improved plate assemblies. This amendment also revises the applicability by adding airplanes. The actions specified by this AD are intended to prevent ceiling panels from falling into the passenger cabin area in the event of failure of certain latch assemblies on the ceiling panels, which could result in consequent injury to the flightcrew and passengers. This action is intended to address the identified unsafe condition.