Summary
This document proposes the supersedure of an existing airworthiness directive (AD), applicable to certain Boeing Model 757- 200 series airplanes, that currently requires inspections to detect cracking on the free edge of the tang, if necessary, and of the fastener holes in the lower spar chord; and various follow-on actions. That AD also provides for an optional terminating action for the repetitive inspections. This action would add inspections to detect additional cracking of the fastener holes in the lower spar chord. This action also adds an optional terminating modification. This proposal is prompted by the issuance of new service information. The actions specified by the proposed AD are intended to detect and correct fatigue cracking in the lower spar chord, which could result in reduced structural integrity of the engine strut.