Airworthiness Directives; Boeing Model 747 Series Airplanes

This amendment adopts a new airworthiness directive (AD), applicable to certain Boeing Model 747 series airplanes, that requires repetitive inspections or checks to detect broken H-11 steel bolts at the wing rear spar side-of-body on the lower chord splice plate and kick fitting; and corrective actions, if necessary. This AD also requires eventual replacement of the existing bolts with new Inconel bolts, which constitutes terminating action for the repetitive inspections. This amendment is prompted by a report of broken bolts at the wing rear spar side-of-body on the lower chord splice plate. The actions specified by this AD are intended to prevent cracking of the bolts due to stress corrosion, which could result in reduced structural integrity of the wing-to-body joint structure.