Summary
This document proposes the supersedure of an existing airworthiness directive (AD), applicable to certain Boeing Model 747-400 and -400D series airplanes, that currently requires installation of strap assemblies on the ceiling panels and rails that support the video monitors. For certain airplanes, this action would require replacement of certain plate assemblies within the ceiling panel strap assemblies with new, improved plate assemblies. This action would also revise the applicability by adding airplanes. The actions specified by the proposed 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.