Airworthiness Directives; Airbus Airplanes

We are adopting a new airworthiness directive (AD) for all Airbus Model A318, A319, A320, and A321 series airplanes. This AD was prompted by a determination that the maintenance actions for airplane systems susceptible to aging must be mandated. This AD requires revising the maintenance or inspection program to incorporate more restrictive maintenance requirements and airworthiness limitations. We are issuing this AD to mitigate the risks associated with aging effects of airplane systems. Such aging effects could change the characteristics leading to an increased potential for failure, which could result in failure of certain life-limited parts, and could reduce the structural integrity or reduce controllability of the airplane.