AD FAA-2017-0480

We propose to adopt a new airworthiness directive (AD) for certain Airbus Model A300 B4-600, B4-600R, and F4-600R series airplanes, and Model A300 C4-605R Variant F airplanes (collectively called Model A300-600 series airplanes); and Model A310 series airplanes. This proposed AD was prompted by cracking in the door sill area of the aft cargo door. This proposed AD would require repetitive inspections of the aft cargo door lower torsion box area, and corrective actions if necessary. We are proposing this AD to address the unsafe condition on these products.