Airworthiness Directives; Boeing Model 777-200 Series Airplanes

This amendment adopts a new airworthiness directive (AD), applicable to certain Boeing Model 777-200 series airplanes, that requires the application of sealant to the upper surface on the wing center section to ensure the integrity of the secondary fuel barrier. This amendment is prompted by reports from the airplane manufacturer that the sealant was inadvertently not applied to portions of the wing center section on certain Boeing Model 777-200 series airplanes. The actions specified by this AD are intended to prevent fuel or fuel vapors from entering the cargo and passenger compartments in the event of a failure of the primary seal or development of a crack in the wing center section structure. Leakage of fuel or fuel vapors into the cargo and passenger compartments could be hazardous to personnel, and could cause a fire in those compartments.