Action
Notice of proposed rulemaking (NPRM).
Summary
We propose to adopt a new airworthiness directive (AD) for certain The Boeing Company Model 737-100, -200, -200C, -300, -400, and -500 series airplanes. This proposed AD was prompted by an evaluation by the design approval holder (DAH) indicating that the bulkhead is subject to widespread fatigue damage (WFD). This proposed AD would require repetitive inspections of the aft pressure bulkhead web for any cracking, incorrectly drilled fastener holes, and elongated fastener holes, and related investigative and corrective actions if necessary. We are proposing this AD to detect and correct fatigue cracking of the aft pressure bulkhead web at the "Y"-chord, which could result in reduced structural integrity of the airplane and rapid decompression of the fuselage.