Airworthiness Directives; Boeing Model 757-200 Series Airplanes

This amendment adopts a new airworthiness directive (AD) that is applicable to certain Boeing Model 757-200 series airplanes. This action 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. This action also provides for optional terminating action for the requirements of this AD. This amendment is prompted by a report of fatigue cracking in the lower spar chord of two Model 757 series airplanes. The actions specified in this AD are intended to detect and correct such fatigue cracking, which could result in reduced structural integrity of the engine strut.