Summary
This document proposes the supersedure of an existing airworthiness directive (AD), applicable to certain Boeing Model 767-200 and -300 series airplanes, that currently requires repetitive inspections to find discrepancies of the barrel nuts that attach the vertical fin to body section 48, and follow-on actions. For certain airplanes, the existing AD requires replacement of certain bolts with new bolts. The existing AD also provides for optional terminating actions for the repetitive inspections. This new action would reduce the compliance time for the inspections; change the torque specification; and mandate eventual replacement of all H-11 steel alloy barrel nuts and bolts with Inconel nuts and bolts, which would end the repetitive inspections. The actions specified by the proposed AD are intended to find and fix corroded, cracked, or broken barrel nuts that attach the vertical fin to body section 48, which could result in reduced structural integrity of the vertical fin attachment joint, loss of the vertical fin, and consequent loss of controllability of the airplane. This action is intended to address the identified unsafe condition.