Airworthiness Directives; Boeing Model 747-400 Series Airplanes

This amendment adopts a new airworthiness directive (AD), applicable to certain Boeing Model 747-400 series airplanes. This action requires repetitive inspections of the E-42 satellite communications (SATCOM) rack and fuselage (supporting) structure to detect fatigue cracking of the area surrounding the fastener holes, and to detect broken or missing fasteners; and corrective actions, if necessary. This amendment is prompted by reports indicating that fatigue cracking and broken and/or missing fasteners were found on the E-42 SATCOM equipment rack structure that attaches to the fuselage structure. The actions specified in this AD are intended to detect and repair fatigue cracking of the E-42 SATCOM rack and its supporting structure, which could result in the SATCOM equipment falling from the rack, loss of SATCOM capabilities, injury to passengers, and reduced controllability of the airplane.