Airworthiness Directives; Airbus Airplanes

We propose to supersede Airworthiness Directive (AD) 2017-15- 17, which applies to certain Airbus Model A300 B4-600R series airplanes, Model A300 C4-605R Variant F airplanes, and Model A300 F4- 600R series airplanes. AD 2017-15-17 requires an inspection of the lower area of a certain frame radius for cracking, and corrective action if necessary. Since we issued AD 2017-15-17, we have determined that repetitive inspections and applicable corrective actions are necessary. This proposed AD would add new repetitive inspections of the lower area of a certain frame radius for cracking, and corrective actions if necessary. We are proposing this AD to address the unsafe condition on these products.