Summary
This document proposes to supersede Airworthiness Directive (AD) 99-11-13, which currently requires inspecting (one-time) the forward, aft, and auxiliary wing spars for cracks on certain Cessna Aircraft Company (Cessna) Model 402C airplanes, and repairing any cracks found. AD 99-11-13 also required reporting the results of the inspection to the Federal Aviation Administration (FAA) to provide data to help FAA determine whether the inspection should be repetitive. After re-evaluating the fatigue analysis for the wing spars on the affected airplanes, FAA has determined that spar cap cracking is not an isolated condition and could continue to develop over the life of the affected airplanes. Therefore, the proposed AD would retain the inspection required in AD 99-11-13, and would make the inspection repetitive. The actions specified by the proposed AD are intended to continue to detect and correct any cracks in the forward, aft, and auxiliary wing spars, which could result in reduced or loss of control of the airplane.