Airworthiness Directives; Boeing Model 747 Series Airplanes

This amendment supersedes an existing airworthiness directive (AD), applicable to certain Boeing Model 747 and 767 series airplanes, that currently requires inspection of the door opening thrusters and door opening/snubbing actuators for proper oil quantity, and modification of the off-wing compartment latching assemblies. This amendment adds a requirement for replacement of the currently installed door opening thrusters with new, improved thrusters for Model 747 series airplanes. This amendment also removes Model 767 series airplanes from the applicability of the AD, since those airplanes are addressed currently in a separate AD. This amendment is prompted by reports indicating that the requirements of the existing AD do not adequately detect leakage of fluid from the actuators. The actions specified by this AD are intended to prevent such leakage, which could result in failure of the escape slide to deploy; such failure could delay and possibly jeopardize the successful emergency evacuation of an airplane.