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, A319-100, A320-200, A321-100, and A321-200 series airplanes, and Model A320-111 airplanes. That AD currently requires an inspection to determine whether certain braking and steering control units (BSCUs) are installed or have ever been installed. For airplanes on which certain BSCUs are installed or have ever been installed, the existing AD requires an inspection of the nose landing gear (NLG) upper support, and corrective action if necessary; and a check of the NLG strut inflation pressure, and an adjustment if necessary. For some of these airplanes, the existing AD also requires a revision to the aircraft flight manual to incorporate an operating procedure to recover normal steering in the event of a steering failure. This new AD instead requires repetitive inspections of the NLG upper support, and related investigative/corrective actions in accordance with new service information; and removes the one-time inspection that was required by the existing AD. This new AD also provides an optional terminating action for the repetitive inspections. This AD results from a report of an incident where an airplane landed with the NLG turned 90 degrees from centerline, and from additional reports of NLG upper support anti-rotation lugs rupturing in service. We are issuing this AD to prevent landings with the NLG turned 90 degrees from centerline, which could result in reduced controllability of the airplane.