Summary
This document proposes the supersedure of an existing airworthiness directive (AD), applicable to certain Boeing Model 737 series airplanes. That AD currently requires a one-time general visual inspection of the seat locks and seat tracks of the flightcrew seats to ensure that the seats lock in position and to verify that lock nuts and bolts of adequate length are installed on the rear track lock bracket, and corrective action, if necessary. This action would revise the applicability of the existing AD by adding airplanes. The actions specified by the proposed AD are intended to prevent uncommanded movement of the flightcrew seats during acceleration and take-off of the airplane, which could result in reduced controllability of the airplane. This action is intended to address the identified unsafe condition.