Airworthiness Directives; Boeing Model 707 and 720 Series Airplanes

This amendment adopts a new airworthiness directive (AD), applicable to certain Boeing Model 707 and 720 series airplanes, that requires replacement of wiring for the fuel boost pumps and override pumps with new wiring, installation of Teflon sleeving on the wiring, and associated actions. This amendment also requires repetitive inspections to detect damage of the wiring or evidence of a fuel leak. This amendment is necessary to detect and correct damaged wiring for the fuel boost pumps and override pumps, which could cause electrical arcing that could puncture the conduit containing the wire, and result in an explosion or fire adjacent to the fuel tank. This action is intended to address the identified unsafe condition.