Airworthiness Directives; Aerospace Technologies of Australia, Nomad N22 and N24 Series Airplanes

概要

This document proposes to supersede AD 85-21-06, which currently requires replacing the attachment fittings of the upper fin rear spar and the fin/horizontal stabilizer on all Aerospace Technologies of Australia (ASTA), Nomad N22 and N24 series airplanes. The proposed action would require removing the upper fin to stub fin forward attachment bolts, inspecting the attachment fittings for cracks, and, if no cracks are found, replacing the attachment bolts with bolts of improved design until the life limit of the attachment fittings is reached, at which time the attachment fittings would be replaced. If cracks are found, the proposed action would require replacing the attachment bolts and attachment fittings. Cracks found in the underhead radius and at the base of the thread of the bolt prompted the proposed AD action. The actions specified by the proposed AD are intended to prevent cracking in the upper fin and horizontal stabilizer attachment fittings, which if not corrected, could result in loss of control of the airplane.