Airworthiness Directives; Boeing Model 747 Series Airplanes Powered by General Electric (GE) CF6-80C2 Series Engines

This amendment adopts a new airworthiness directive (AD), applicable to certain Boeing Model 747 series airplanes powered by GE CF6-80C2 series engines, that requires repetitive inspections and torque checks to find discrepancies of the fasteners that attach the diagonal brace fittings of the lower spar to the inboard engine struts, and modification of the fasteners if discrepancies are found. This amendment also requires eventual modification of all the fasteners, which ends the repetitive inspections and checks. The actions specified by this AD are intended to find and fix discrepant fasteners of the diagonal brace fittings, which could result in reduced structural integrity of the diagonal brace-to-strut attachment, and possible separation of the strut and engine from the airplane. This action is intended to address the identified unsafe condition.