Summary
This document proposes the adoption of a new airworthiness directive (AD) that is applicable to certain Boeing Model 747 series airplanes. This proposal would require repetitive detailed visual inspections to detect corrosion on the rear spar web of the wing center section and adjacent bulkhead fittings at body station 1241; and corrective action, if necessary. This proposal is prompted by reports of corrosion found on the rear spar web and bulkhead fitting. The actions specified by the proposed AD are intended to detect and correct such corrosion, which could cause cracking of the rear spar web, and result in a fuel leak and consequent fire/explosion in the wheel well of the main landing gear.