Summary
We propose to adopt a new airworthiness directive (AD) for certain The Boeing Company Airplanes Model 737-100, -200, -200C, -300, -400, -500, -600, -700, -700C, -800, and -900 series airplanes. This proposed AD was prompted by a report that the seat track attachment of body station 520 flexible joint is structurally deficient in resisting a 9g forward emergency load condition in certain seating configurations. This proposed AD would require replacing the pivot link assembly on certain seats, and modifying or replacing the seat track link assemblies on certain seats. Also, for certain airplanes, this proposed AD would require installing a new seat track link assembly. We are proposing this AD to prevent seat detachment in an emergency landing, which could cause injury to occupants of the passenger compartment and affect emergency egress.