Airworthiness Directives; Airbus Model A318, A319, A320, and A321 Airplanes

The FAA is superseding an existing airworthiness directive (AD), which applies to all Airbus Model A318-100 and A319-100 series airplanes, Model A320-111 airplanes, and Model A320-200, A321-100, and A321-200 series airplanes. That AD currently requires repetitive inspections of the upper and lower attachments of the trimmable horizontal stabilizer actuator (THSA) to measure for proper clearance and to detect cracks, damage, and metallic particles. The existing AD also requires corrective actions, if necessary, and reports of inspection findings. This new AD shortens the repetitive interval for inspecting the upper THSA attachment. This AD results from new test results on the secondary load path, which indicated the need to shorten the repetitive interval for inspecting the upper THSA attachment. We are issuing this AD to detect and correct failure of the THSA's primary load path, which could result in latent (undetected) loading and eventual failure of the THSA's secondary load path and consequent uncontrolled movement of the horizontal stabilizer and loss of control of the airplane.