Summary
This document proposes the adoption of a new airworthiness directive (AD) that is applicable to certain Boeing Model 747-200, - 300, and -400 series airplanes. This proposal would require repetitive inspections to detect cracking of the front spar web of the center section of the wing, and repair, if necessary. This proposal is prompted by reports of fatigue cracking found in the front spar web. The actions specified by the proposed AD are intended to prevent the leakage of fuel into the forward cargo bay, as a result of fatigue cracking in the front spar web, which could result in a potential fire hazard.