Airworthiness Directives; Airbus Airplanes

We propose to supersede airworthiness directive (AD) 2000-10- 18, that applies to certain Airbus Model A300 series airplanes; Model A300 B4-600, B4-600R, F4-600R series airplanes, and Model A300 C4-605R Variant F airplanes (collectively called Model A300-600 series airplanes); and Model A310 series airplanes. AD 2000-10-18 requires repetitive inspections to detect cracks in the lower spar of the engine pylons between ribs 6 and 7, and repair if necessary. Since we issued AD 2000-10-18, we have determined that the compliance times for the initial inspection and the repetitive intervals must be reduced to allow timely detection of cracks in the engine pylon's lower spar between ribs 6 and 7. This proposed AD would reduce the compliance times for the initial inspection and the repetitive intervals. We are proposing this AD to prevent fatigue cracking, which could result in reduced structural integrity of the engine pylon's lower spar, and possible separation of the engine from the airplane.