Airworthiness Directive · Amendment 39-13001 · McDonnell Douglas Model DC-9-11, -12, -13, -14, -15, and -15F Airplanes; Model DC-9-21 Airplanes; Model DC-9-31, -32, -32 (VC-9C), -32F, -32F (C-9A, C-9B), -33F, -34, and -34F Airplanes; Model DC-9-41 Airplanes; Model DC-9-51 Airplanes; Model DC-9-81 (MD-81), DC-9-82 (MD-82), DC-9-83 (MD-83), and DC-9-87 (MD-87) Airplanes; and Model MD-88 Airplanes
McDonnell Douglas Model DC-9-11, -12, -13, -14, -15, and -15F Airplanes; Model DC-9-21 Airplanes; Model DC-9-31, -32, -32 (VC-9C), -32F, -32F (C-9A, C-9B), -33F, -34, and -34F Airplanes; Model DC-9-41 Airplanes; Model DC-9-51 Airplanes; Model DC-9-81 (MD-81), DC-9-82 (MD-82), DC-9-83 (MD-83), and DC-9-87 (MD-87) Airplanes; and Model MD-88 Airplanes
This AD applies to the following airplanes, certificated in any category, as listed in Boeing Alert Service Bulletin DC9-24A191, Revision 01, dated January 9, 2002: McDonnell Douglas Model DC-9-11, DC-9-12, DC-9-13, DC-9-14, DC-9-15, and DC-9-15F airplanes DC-9-21 airplanes DC-9-31, DC-9-32, DC-9-32 (VC-9C), DC-9-32F, DC-9-32F (C-9A, C-9B), DC-9-33F, DC-9-34, and DC-9-34F airplanes DC-9-41 airplanes DC-9-51 airplanes DC-9-81 (MD-81), DC-9-82 (MD-82), DC-9-83 (MD-83), and DC-9-87 (MD- 87) airplanes MD-88 airplanes
This amendment adopts a new airworthiness directive (AD), applicable to certain McDonnell Douglas airplanes, that requires replacement of certain power relays, and subsequent repetitive cleaning, inspecting, repairing, and testing of certain replaced power relays. This amendment is prompted by reports indicating that the alternating current (AC) cross-tie relay shorted out internally, which caused severe smoke and burn damage to the relay, aircraft wiring, and adjacent panels. The actions specified by this AD are intended to prevent internal arcing of the left and right generator power relays, auxiliary power relays, and external power relays, and consequent smoke and/or fire in the cockpit and cabin.
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.
