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

The FAA is superseding an existing airworthiness directive (AD) that applies to certain Airbus Model A319, A320, and A321 airplanes. The existing AD currently requires a one-time ultrasonic inspection for certain airplanes, and repetitive detailed inspections for all airplanes, for cracking in the forward lug of the support rib 5 fitting of both main landing gear (MLG), and repair if necessary. The existing AD also provides for optional terminating actions. This AD removes the requirement for the one-time ultrasonic inspection and reduces the compliance time and repetitive interval for the detailed inspection of all airplanes. This AD also adds certain Airbus Model A318 airplanes to the applicability. This AD continues to provide optional terminating action for certain airplanes, as well as other optional methods of complying with the AD's requirements. This AD results from a new crack that was found in the forward lug of the MLG support rib 5 fitting. We are issuing this AD to detect and correct cracking in the forward lug of the MLG, which could result in failure of the lug and consequent collapse of the MLG during takeoff or landing.