Summary
This document proposes to adopt a new airworthiness directive (AD) that would apply to Twin Commander Aircraft Corporation 500, 600, and 700 series airplanes. The proposed action would require installing access holes in both wing leading edges and repetitively inspecting the forward attach brackets and straps for cracks. Reports of cracks in the wing to fuselage attachment brackets and straps, wing station (WS) 24, and fuselage frames prompted the proposed action. The actions specified by the proposed AD are intended to detect cracks at the wing to fuselage attach points, which, if not detected and corrected, could cause structural failure and loss of control of the airplane.