Airworthiness Directives; The Boeing Company Model 737-100, -200, -200C, -300, -400, and -500 Series Airplanes

The FAA is superseding an existing airworthiness directive (AD) that applies to all Model 737-100, -200, -200C, -300, -400, and - 500 series airplanes. That AD currently requires a one-time inspection for scribe lines and cracks in the fuselage skin at certain lap joints, butt joints, external repair doublers, and other areas; and related investigative/corrective actions if necessary. This new AD expands the area to be inspected and, for certain airplanes, requires earlier inspections for certain inspection zones. This AD results from additional detailed analysis of fuselage skin cracks adjacent to the skin lap joints on airplanes that had scribe lines. The analysis resulted in different inspection zones, thresholds and repetitive intervals, and airplane groupings. We are issuing this AD to prevent rapid decompression of the airplane due to fatigue cracks resulting from scribe lines on pressurized fuselage structure.