Airworthiness Directive · Amendment 39-9901 · The Boeing Company Airplanes
The Boeing Company Airplanes
This AD applies to The Boeing Company 737-300 Series, 737-400 Series, 737-500 Series.
The models as the FAA's AD index lists them. The serial ranges, installed parts and exceptions are in the AD itself: read it at the FAA.
This amendment adopts a new airworthiness directive (AD), applicable to certain Boeing Model 737-300, -400, and -500 series airplanes, that requires modification of the system that detects a loss of tension in the cable controlling the flaps by removing the shim from behind the proximity switch and by trimming the switch bracket. This amendment is prompted by reports that the switch bracket can impair the movement of a pulley arm mechanism, ultimately preventing the detection system from operating. The actions specified by this AD are intended to prevent such impairment, which could result in movement of the flaps without action by the pilot, and ultimately cause reduced controllability of the airplane.
The aircraft, engines and makers this AD names, by the model designations in its text. A model listed here may still be outside the AD's serial ranges.
