Airworthiness Directive · Amendment 39-11386 · McDonnell Douglas Model DC-9, DC-9-80 and C-9 (Military) Series Airplanes, and Model MD-88 Airplanes
McDonnell Douglas Model DC-9, DC-9-80 and C-9 (Military) Series Airplanes, and Model MD-88 Airplanes
Model DC-9-10, -20, -30, -40, and -50 series airplanes; Model DC-9-81 (MD-81), DC-9-82 (MD-82), DC-9-83 (MD-83), and DC-9-87 (MD-87) series airplanes; Model MD-88 airplanes; and C-9 (military) series airplanes; as listed in the McDonnell Douglas Service Bulletin DC9-36-012, Revision 04, dated October 16, 1998; certificated in any category.
This amendment adopts a new airworthiness directive (AD), applicable to certain McDonnell Douglas Model DC-9, DC-9-80 and C-9 (military) series airplanes, and Model MD-88 airplanes, that requires revising the wiring of the air conditioning pneumatic supply control, if applicable, and revising the wiring of the pneumatic augmentation valve. This amendment is prompted by a report indicating that the pneumatic augmentation valve may go fully open when an engine fails during initial climb prior to deactivation of the second segment climb switch. The actions specified by this AD are intended to prevent opening of the pneumatic augmentation valve, which could result in significant loss of thrust from the remaining engine and consequent inadequate initial climb performance 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.
