Summary
This document proposes the adoption of a new airworthiness directive (AD) that is applicable to certain Boeing Model 747-400 series airplanes. This proposal would require modification of the engine fuel feed system. This proposal is prompted by reports indicating that the coupling nut on the fuel tube on the outboard strut (engine position 1) fractured. The actions specified by the proposed AD are intended to prevent such fracturing of the coupling nut, which could result in release of fuel onto the engine cowling and a subsequent fire.