Summary
This document proposes the supersedure of an existing airworthiness directive (AD), applicable to certain Boeing Model 727 series airplanes, that currently requires repetitive inspections of the front spar web between the upper and lower seals of the center section of the wings, and repair, if necessary. That AD also provides for an optional terminating modification for the repetitive inspections. This action would require a new terminating modification for the repetitive inspections. For certain airplanes, this action would require new repetitive inspections to detect discrepancies of the front spar web. This proposal is prompted by a report indicating that the optional terminating modification in the existing AD does not address the identified unsafe condition. The actions specified by the proposed AD are intended to prevent fatigue cracks in the front spar web, which could lead to fuel leakage into the air-conditioning distribution bay and/or depressurization of the cabin, and to prevent fuel fumes in the cabin of the airplane.