Summary
This document proposes the supersedure of an existing airworthiness directive (AD), applicable to certain Boeing Model 747 series airplanes, that currently requires repetitive inspections and torque checks of the hanger fittings and strut forward bulkhead of the forward engine mount and adjacent support structure, and corrective actions, if necessary. The existing AD also provides for optional terminating action for the repetitive inspections and checks. This action would mandate certain new repetitive torque checks and the previously optional terminating action. The actions specified by the proposed AD are intended to prevent loose fasteners and associated damage to the hanger fittings and bulkhead of the forward engine mount, which could result in separation of the engine from the airplane.