AD FAA-2018-0900

We are adopting a new airworthiness directive (AD) for certain The Boeing Company Model 737-100, -200, -200C, -300, -400, and -500 series airplanes. This AD was prompted by reports of cracking in the frame web, frame integral inboard chord, and fail-safe chord on multiple airplanes in multiple locations between stringers S-10 and S- 17 above the passenger floor, in addition to an evaluation by the design approval holder (DAH) indicating that certain fuselage frame splices are subject to widespread fatigue damage (WFD). This AD requires repetitive inspections of certain fuselage upper frames, side frames, fail-safe chords, inboard chords, frame webs, and stringers; an inspection for open tooling holes and the presence of repairs in certain inspection zones; and applicable on-condition actions. We are issuing this AD to address the unsafe condition on these products.