Summary
We propose to adopt a new airworthiness directive (AD) for all The Boeing Company Model 737-600, -700, -700C, -800, -900, and 900ER series airplanes. This proposed AD was prompted by an evaluation by the design approval holder (DAH) indicating that the S-14L and S-14R lap splices are subject to widespread fatigue damage (WFD). This proposed AD would require repetitive low frequency eddy current inspections for cracking in the lower fastener row of the S-14L and S-14R lap splices and repair if necessary. We are proposing this AD to detect and correct widespread cracking in the S-14L and S-14R lap splices that could rapidly link up and result in possible rapid decompression and reduced structural integrity of the airplane.