Summary
This document proposes the adoption of a new airworthiness directive (AD) that is applicable to certain Boeing Model 707 and 720 series airplanes. This proposal would require 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 proposal also would require repetitive inspections to detect damage of the wiring or evidence of a fuel leak. This action 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.