Summary
This document revises an earlier proposed airworthiness directive (AD), which would have superseded an existing AD that is applicable to certain Boeing Model 727 series airplanes. The existing AD currently requires inspections to detect cracks of the elevator rear spar, and repair, if necessary; and provides for a terminating action for the inspections. The previously proposed action would have added a one-time inspection to verify that proper clearance exists between the shear plate and the radii of the elevator rear spar on airplanes on which the terminating action had been accomplished. This action revises the proposed rule by adding new inspections to detect cracks and loose brackets of the elevator rear spar; adding a new terminating modification for the inspections; and expanding the applicability of the rule to include additional airplanes. Additionally, it would supersede two previously issued AD's. The proposed actions are intended to prevent cracking in elements of the elevator rear spar assembly, which could result in excessive free play of the elevator control tab and possible tab flutter.