Action
Final rule.
Summary
We are adopting a new airworthiness directive (AD) for certain The Boeing Company Model 777-200, 777-200LR, 777-300ER, and 777F series airplanes. This AD was prompted by a report indicating that sealant might not have been applied in production to the wing skin panel gaps above certain underwing fittings. This AD would require an inspection for missing sealant, and applicable other specified, related investigative, and corrective actions. We are proposing this AD to detect and correct missing sealant from the wing skin panel gaps above the underwing fittings, which could result in corrosion and fatigue cracking in the wing skin panel, and consequent loss of limit load capability of the wing skin and potential subsequent structural failure of the wings.