Summary
This document proposes the adoption of a new airworthiness directive (AD) that is applicable to certain Boeing Model 737-100, - 200, -300, -400, and -500 series airplanes. This proposal would require repetitive inspections to detect cracking of various areas of the forward pressure bulkhead, and repair, if necessary. This proposal would also require certain preventive modifications, which, when accomplished, would terminate the repetitive inspections for most, but not all, of the affected areas. This proposal is prompted by reports indicating that numerous fatigue cracks were found on critical areas of the forward pressure bulkhead. The actions specified by the proposed AD are intended to prevent such fatigue cracking, which could result in rapid decompression of the airplane fuselage.