Summary
This document proposes to revise an earlier proposed airworthiness directive (AD) that the Federal Aviation Administration (FAA) issued against Ayres Corporation (Ayres) S2R series and Model 600 S2D airplanes. The earlier proposed rule would supersede the existing AD with a new AD that would require you to repetitively inspect the \1/ 4\-inch and \5/16\-inch bolt hole areas on the lower spar caps for fatigue cracking, replace any lower spar cap where fatigue cracking is found, and report any fatigue cracking. The existing AD was the result of an accident of an Ayres S2R series airplane where the wing separated from the airplane in flight. Based upon our continuous evaluation of this situation, we are making minor changes to the most recent proposal; specifically regrouping the affected airplanes into six groups, adjusting the repetitive inspection intervals, providing alternatives for inspection methods, and including modification alternatives to replacing the spar cap. By reopening the comment period, we are allowing you the opportunity to comment on these changes. The actions specified by the proposed AD are intended to detect and correct fatigue cracking of the lower spar caps, which could result in the wing separating from the airplane with consequent loss of control of the airplane.