Summary
We propose to supersede Airworthiness Directive (AD) 97-20-07, 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). AD 97-20-07 requires repetitive inspections to detect fatigue cracking in the left and right wings in the area where the top skin attaches to the center spar, and repair or modification of this area if necessary. Since we issued AD 97-20-07, we have determined that the inspection compliance time and repetitive inspection interval must be reduced to allow timely detection of cracking in the left and right wings in the area where the top skin attaches to the center spar. This proposed AD would reduce the inspection compliance time and repetitive inspection intervals. We are proposing this AD to detect and correct this cracking, which could reduce the residual strength of the top skin of the wings, and consequently affect the structural integrityof the airframe.