Airworthiness Directive · Amendment 39-15183 · Boeing Model 737-300, -400, and -500 Series Airplanes
Boeing Model 737-300, -400, and -500 Series Airplanes
This AD applies to Boeing Model 737-300, -400, and -500 series airplanes, variable numbers PS971 through PS978, PT187, and PT188, certificated in any category.
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.
You are responsible for having the actions required by this AD performed within the compliance times specified, unless the actions have already been done.
Within 90 days after the effective date of this AD, do 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 tracklock bracket, in accordance with the Accomplishment Instructions of Boeing Alert Service Bulletin 737-25A1363, Revision 2, dated May 2, 2006.
(1) If the seat lock pin fully engages in all lock positions of the seat track, and the rear track lock bracket is correctly installed: No further action is required by this AD.
(2) If the seat lock pin does not fully engage in all positions of the seat track, before further flight, make sure the flightcrew seat operates correctly, in accordance with the service bulletin.
(3) If the lock nuts and bolts of adequate length are not installed on the rear tracklock bracket, before further flight, rework the flightcrew seat in accordance with the service bulletin.
Note 1: For the purposes of this AD, a general visual inspection is: “A visual examination of an interior or exterior area, installation, or assembly to detect obvious damage, failure, or irregularity. This level of inspection is made from within touching distance unless otherwise specified. A mirror may be necessary to ensure visual access to all surfaces in the inspection area. This level of inspection is made under normally available lighting conditions such as daylight, hangar lighting, flashlight, or droplight and may require removal or opening of access panels or doors. Stands, ladders, or platforms may be required to gain proximity to the area being checked.”
Note 2: Boeing Alert Service Bulletin 737-25A1363, Revision 2, dated May 2, 2006, refers to IPECO Service Bulletin A001-25-47, Issue 2, dated July 31, 2002, as an additional source of service information for accomplishment of the inspection and rework required by paragraphs (f) and (f)(3) of this AD, respectively.
(g) Actions done before the effective date of this AD in accordance with Boeing Alert Service Bulletin 737-25A1363, dated November 5, 1998; or Revision 1, dated March 28, 2002, is acceptable for compliance with the corresponding action specified in this AD.
