AD FAA-2017-0330

We are adopting a new airworthiness directive (AD) for certain The Boeing Company Model 737-300, -400, and -500 series airplanes. This AD was prompted by an evaluation by the design approval holder (DAH) indicating that the lower skin at the skin lap splice lower fastener row is subject to widespread fatigue damage (WFD). This AD requires repetitive inspections for cracking in the skin lap splice at the lower fastener row, and repair if necessary. We are issuing this AD to address the unsafe condition on these products.