Airworthiness Directives; Boeing Model 737 Series Airplanes

This document publishes in the Federal Register an amendment adopting Airworthiness Directive (AD) T95-06-53 that was sent previously to all known U.S. owners and operators of Boeing Model 737 series airplanes by individual telegrams. This AD requires identification of the part and serial numbers of the main rudder power control unit (PCU), and replacement of certain PCU's with serviceable parts, if necessary. This amendment is prompted by reports indicating that certain modified rudder PCU's malfunctioned and failed functional retesting. The actions specified by this AD are intended to prevent the rudder actuator piston and the rudder from operating with reduced force capability or moving in a direction opposite the intended direction due to malfunctioning of the rudder PCU; these conditions could result in reduced controllability of the airplane.