Summary
This document proposes the adoption of a new airworthiness directive (AD) that is applicable to all Boeing Model 727 series airplanes. This proposal would require repetitive inspections for cracking of the upper chord of the rear spar of the wing, and corrective action, if necessary. This action is necessary to find and fix such cracking, which could result in fuel leaking through the cracks, reduced structural integrity of the wing, and separation of the wing from the airplane. This action is intended to address the identified unsafe condition.