Action
Final rule.
Summary
We are adopting a new airworthiness directive (AD) for certain The Boeing Company Model 747-200B, 747-300, 747-400, 747-400D, and 747- 400F series airplanes. This AD was prompted by a report of cracking in both the aluminum strut side skin, and corrosion resistant steel (CRES) outer spring beam support fitting. This AD requires inspections, related investigative and corrective actions, and a fastener installation modification. We are issuing this AD to address the unsafe condition on these products.