Summary
We propose to adopt a new airworthiness directive (AD) for certain The Boeing Company Model 737-600, -700, -700C, -800, and -900 series airplanes. This proposed AD was prompted by an evaluation by the design approval holder (DAH) indicating that the aft pressure bulkhead is subject to widespread fatigue damage (WFD). This proposed AD would require repetitive inspections of the aft pressure bulkhead web for any cracking, crack indications, discrepant fastener holes, and corrosion; and corrective actions if necessary. We are proposing this AD to detect and correct cracks in the aft pressure bulkhead web, which could result in an uncontrolled decompression of the fuselage.