Summary
We propose to adopt a new airworthiness directive (AD) for all Model 727, 727C, 727-100, 727-100C, 727-200, and 727-200F series airplanes. This proposed AD would require repetitive detailed inspections of the aft pressure bulkhead web for cracking, and repair if necessary. For certain airplanes, this proposed AD also would provide for an optional preventative modification of the aft pressure bulkhead web, which would terminate certain repetitive detailed inspections. This proposed AD results from reports of cracks in the aft pressure bulkhead web. We are proposing this AD to detect and correct cracking in the aft pressure bulkhead web, which could adversely affect the structural integrity of the airplane, resulting in difficulty maintaining cabin pressurization or rapid decompression of the airplane.