Summary
We propose to adopt a new airworthiness directive (AD) for certain Model DC-8-11, DC-8-12, DC-8-21, DC-8-31, DC-8-32, DC-8-33, DC- 8-41, DC-8-42, and DC-8-43 airplanes, DC-8-50 series airplanes, DC-8F- 54 and DC-8F-55 airplanes, DC-8-60 series airplanes, DC-8-60F series airplanes, DC-8-70 series airplanes, and DC-8-70F series airplanes. This proposed AD would require repetitive high frequency eddy current or repetitive low frequency eddy current inspections for cracks on the area around certain fasteners of the access opening doubler on the left and right wing center spar lower cap, and repair, if necessary. This proposed AD results from reports that cracks in the center spar lower cap and, in some cases, the web of the spar, have been found at stations Xrs=168.00, Xrs=251.00, and Xrs=358.00. We are proposing this AD to detect and correct cracks in the area around certain fasteners of the access opening doubler on the left and right wing center spar lower cap, which could compromise the structural integrity of the wing structure.