Summary
We propose to adopt a new airworthiness directive (AD) for all McDonnell Douglas airplanes identified above. This proposed AD would require repetitive inspections of the lower skin and stringers at stations Xw = 408 and Xw = -408 and corrective actions if necessary. This proposed AD results from reports of cracks in the skins and stringers at the end fasteners common to the stringer end fittings at station Xw = 408 and Xw = -408 wing splice joints. We are proposing this AD to detect and correct fatigue cracking in the skins and stringers at the end fasteners common to the stringer end fittings at a certain station and wing splice joints, which could result in wing structure that might not sustain limit load, and consequent loss of structural integrity of the wing.