Airworthiness Directives; Boeing Model 737-300, -400, and -500 Series Airplanes

The FAA is adopting a new airworthiness directive (AD) for certain Boeing Model 737-300, -400, and -500 series airplanes. This AD requires an 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 tracklock bracket, and corrective actions if necessary. This AD results from a report indicating that the captain's seat slid aft and jammed during taxi. We are issuing this AD 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.