Airworthiness Directives; Airbus Model A319, A320, and A321 Series Airplanes

This amendment supersedes an existing airworthiness directive (AD), applicable to certain Airbus Model A319, A320, and A321 series airplanes, that currently requires a one-time ultrasonic inspection to detect disbonding of the skin attachments at the stringers and spars of the vertical stabilizer, repair, if necessary, and, for certain airplanes, prior or concurrent modification of the vertical stabilizer to ensure proper reinforcement of its attachment to the skin. This amendment adds repetitive ultrasonic inspections of the subject area, and repair, if necessary. It also adds installation of fasteners to reinforce the bonds to the skin, which terminates the repetitive inspections. This amendment is prompted by issuance of mandatory continuing airworthiness information by a foreign civil airworthiness authority. The actions specified by this AD are intended to prevent failure of the bonds of the vertical stabilizer spar boxes to the skin, which could lead to reduced structural integrity of the spar boxes.