Airworthiness Directive · Amendment 39-12700 · McDonnell Douglas Model DC-9-10, -20, -30, -40, and -50 Series Airplanes; and C-9 Airplanes
McDonnell Douglas Model DC-9-10, -20, -30, -40, and -50 Series Airplanes; and C-9 Airplanes
Model DC-9-10, -20, -30, -40, and -50 series airplanes, and C-9 airplanes; certificated in any category; equipped with a floor level hinged (ventral) door of the aft pressure bulkhead; as listed in McDonnell Douglas Service Bulletin DC9-53- 137, Revision 07, dated February 6, 2001; except for those airplanes on which the modification required by paragraph (d) or (e) of AD 96- 10-11, amendment 39-9618, or paragraph K. of AD 85-01-02 R1, amendment 39-5241, has been done.
This amendment adopts a new airworthiness directive (AD), applicable to certain McDonnell Douglas Model DC-9-10, -20, -30, -40, and -50 series airplanes; and C-9 airplanes; that requires repetitive visual and x-ray inspections to detect cracks of the upper and lower corners and upper center of the door cutout of the aft pressure bulkhead; corrective actions, if necessary; and follow-on actions. For certain airplanes, the amendment also requires modification of the ventral aft pressure bulkhead. The actions specified by this AD are intended to detect and correct fatigue cracks in the corners and upper center of the door cutout of the aft pressure bulkhead, which could result in rapid decompression of the fuselage and consequent reduced structural integrity of the airplane. This action is intended to address the identified unsafe condition.
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.
