Airworthiness Directives; Airbus Model A300 B4-600, B4-600R, and F4-600R Series Airplanes, and Model C4-605R Variant F Airplanes (Collectively Called A300-600 Series Airplanes)

The FAA is superseding an existing airworthiness directive (AD) that applies to all Airbus Model A300-600 series airplanes. That AD currently requires inspections of the lower door surrounding structure to detect cracks and corrosion; inspections to detect cracking of the holes of the corner doublers, the fail-safe ring, and the door frames of the door structures; and repair if necessary. That AD also provides for optional terminating action for certain inspections. This new AD retains all requirements of the existing AD, mandates the previously optional terminating action, reduces the applicability of the existing AD, and adds repetitive inspections behind scuff plates for certain affected airplanes. This AD results from a determination that further rulemaking is necessary to improve the fatigue behavior of the cabin door surroundings. We are issuing this AD to prevent corrosion between the scuff plates at exit and cargo doors and fatigue cracks originating from certain fastener holes located in adjacent structure, which could result in reduced structural integrity of the door surroundings.