Airworthiness Directive · Amendment 39-14010 · Boeing Model 757-200 Series Airplanes
Boeing Model 757-200 Series Airplanes
This AD applies to Boeing Model 757-200 series airplanes, certificated in any category; as identified in Boeing Service Bulletin 757-33-0050, Revision 2, dated December 4, 2003.
The FAA is adopting a new airworthiness directive (AD) for certain Boeing Model 757-200 series airplanes. This AD requires modifying the wiring of the test ground signal for the master dim and test system circuit in the flight compartment. This AD is prompted by a report that the master dim and test system circuit does not have wiring separation of the test ground signal for redundant equipment in the flight compartment. We are issuing this AD to prevent a single fault failure during flight, which could result in test patterns instead of the selected radio frequencies showing on the communications panel. These conditions could adversely affect voice and transponder communication capability between the flightcrew and air traffic control, which could result in increased pilot workload.
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 60 months after the effective date of this AD: Modify the wiring of the test ground signal for the master dim and test system circuit in the flight compartment by doing all the applicable actions specified in Boeing Service Bulletin 757-33-0050, Revision 2, dated December 4, 2003.
Modifications done before the effective date of this AD in accordance with Boeing Special Attention Service Bulletin 757-33-0050, dated August 15, 2002; or Revision 1, dated January 30, 2003; are considered acceptable for compliance with paragraph (f) of this AD.
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.
