Summary
The FAA proposes to adopt a new airworthiness directive (AD) for certain Boeing Model 737-100, -200, -200C, -300, -400, and -500 series airplanes. This proposed AD would require the following: Repetitive eddy current inspections for cracks of the countersunk rivet holes in the lower lobe, adjacent to the radio altimeter cutouts; additional inspections, for certain airplanes, for cracks and/or corrosion; and further investigative and corrective action if any crack is found. This proposed AD also would provide an optional terminating action for the repetitive inspections. This proposed AD was prompted by reports of cracks in the fuselage skin of the lower lobe. We are proposing this AD to detect and correct fatigue cracks of the countersunk rivet holes, which could result in cracks of the fuselage skin of the lower lobe, and consequent rapid depressurization of the cabin.