Summary
This document proposes the supersedure of an existing airworthiness directive (AD), applicable to certain Boeing Model 737 series airplanes. The existing AD currently requires repetitive inspections for cracking and corrosion of the pressure bulkhead at body station (BS) 1016, and follow-on actions. This action would expand the applicability of the existing AD to include additional airplanes and require new repetitive inspections to detect cracking and corrosion of the aft pressure bulkhead at BS 1016, and follow-on actions. This action is necessary to detect and correct corrosion or cracking of the aft pressure bulkhead at BS 1016, which could result in loss of the aft pressure bulkhead web and stiffeners and consequent rapid decompression of the fuselage. This action is intended to address the identified unsafe condition.