Summary
This document revises an earlier proposed airworthiness directive (AD), applicable to certain Boeing Model 757 series airplanes equipped with Rolls Royce RB211 engines, that would have superseded an existing AD that currently requires modification of the nacelle strut and wing structure. The proposed AD would have added a one-time inspection of the middle gusset of the inboard side load fitting for proper alignment, and a one-time inspection of certain fastener holes in the lower spar fitting of the nacelle strut and wing structure for cracking, and corrective actions, if necessary. For certain airplanes, the proposed AD would have required installation of new fasteners. This new action revises the proposed rule by reducing a certain compliance time and adding new inspections. The actions specified by this new proposed AD are intended to prevent fatigue cracking in primary strut structure and consequent reduced structural integrity of the strut. These actions are intended to address the identified unsafe condition.