Summary
The FAA proposes to supersede an existing airworthiness directive (AD) that applies to certain Boeing Model 767 series airplanes. The existing AD currently requires repetitive inspections to detect discrepancies of the eight aft-most fastener holes in the horizontal tangs of the midspar fitting of the strut, and corrective actions if necessary. That AD also provides an optional terminating action for the repetitive inspections. This proposed AD would add repetitive inspections for cracks of the closeout angle that covers the two aft-most fasteners in the lower tang of the midspar fitting, and related investigative and corrective actions if necessary. This proposed AD also would reduce the inspection interval of the upper tang of the outboard midspar fitting; and would provide an optional terminating action for the repetitive inspections. This proposed AD is prompted by a report of a crack in a closeout angle that covers the two aft-most fasteners in the lower tang of the midspar fitting; and the discovery of a crack in the lower tang of the midspar fitting under the cracked closeout angle. We are proposing this AD to prevent fatigue cracking in the primary strut structure and reduced structural integrity of the strut, which could result in separation of the strut and engine.