Summary
The FAA proposes to supersede an existing airworthiness directive (AD) that applies to all Airbus Model A300 B2 and B4 series airplanes; and Model A300 B4-600, B4-600R, and F4-600R (collectively called A300-600) series airplanes. The existing AD currently requires repetitive inspections to detect cracking of the upper radius of the forward fitting of frame 47, and repair if necessary. This proposed AD would reduce inspection thresholds and repetitive intervals, and add related investigative and corrective actions. This proposed AD also would provide an optional terminating action for the repetitive inspections only for airplanes with cracking that is within certain limits. This proposed AD results from reports of additional cracking in airplanes that were inspected in accordance with the existing AD. We are proposing this AD to detect and correct fatigue cracking of the left and right upper radius at frame 47, which could propagate and result in reduced structural integrity ofthe airplane.