Airworthiness Directive · Amendment 39-11961 · McDonnell Douglas Model DC-9-10, -20, -30, -40, and -50 Series Airplanes and C-9 (Military) Airplanes
McDonnell Douglas Model DC-9-10, -20, -30, -40, and -50 Series Airplanes and C-9 (Military) Airplanes
Model DC-9-10, -20, -30, -40, and -50 series airplanes and C-9 (military) airplanes; as listed in McDonnell Douglas Service Bulletin DC9-54-030, Revision 06, dated November 11, 1999; certificated in any category; except for those airplanes on which Special Change Notification 1269A, dated August 11, 1965, or Service Rework Drawing SR09540004, Change “E,” dated September 21, 1992, Change “F,” dated April 19, 1995, Change “G,” dated May 6, 1997, or Change “H,” dated July 12, 1997, has been accomplished.
Note 1: This AD applies to each airplane identified in the preceding applicability provision, regardless of whether it has been otherwise modified, altered, or repaired in the area subject to the requirements of this AD. For airplanes that have been modified, altered, or repaired so that the performance of the requirements of this AD is affected, the owner/operator must request approval for an alternative method of compliance in accordance with paragraph (f) of this AD. The request should include an assessment of the effect of the modification, alteration, or repair on the unsafe condition addressed by this AD; and, if the unsafe condition has not been eliminated, the request should include specific proposed actions to address it.
This amendment supersedes an existing airworthiness directive (AD), applicable to certain McDonnell Douglas Model DC-9-10, -20, -30, -40, and -50 series airplanes, that currently requires repetitive radiographic and ultrasonic or eddy current inspections, and modification of the upper cap of the front spar of the left and right engine pylons, if necessary. This amendment requires new, improved x- ray and eddy current inspections to detect cracks of the upper cap of the front spar of the left and right engine pylons, and repetitive inspections or corrective actions, if necessary. This amendment also requires modification of the subject area, which constitutes terminating action for the repetitive inspection requirements. This amendment is prompted by additional reports of fatigue cracking in the subject area of these airplanes. The actions specified by this AD are intended to prevent failure of the upper cap of the front spar of the engine pylons due to fatigue cracking, and consequent reduced structural integrity of the airplane.
To prevent failure of the front spar attachment and upper cap of the engine pylons due to fatigue cracking, and consequent reduced structural integrity of the airplane, accomplish the following:
(a) Prior to the accumulation of 9,800 total flight hours, or within the next 1,800 flight hours after August 23, 1977 (the effective date of AD 77-14-19, amendment 39-2971), whichever occurs later, unless accomplished previously within the last 1,800 flight hours, accomplish the radiographic and ultrasonic or eddy current inspections in accordance with the instructions in Douglas Service Bulletin 54-30, dated January 19, 1977. Repeat the inspection thereafter at intervals not to exceed 3,600 flight hours. For those operators who have conducted only the radiographic inspections in accordance with Douglas All Operators Letter AOL 9-835, dated October 30, 1974, perform the ultrasonic or eddy current inspections, and thereafter, the radiographic and ultrasonic or eddy current inspection in accordance with the requirements of this AD, as applicable.
Note 2: Inspections accomplished prior to the effective date of this AD in accordance with McDonnell Douglas Service Bulletin 54-30, Revision 1, dated June 29, 1977, Revision 2, dated October 27, 1978, Revision 3, dated April 30, 1986, or Revision 4, dated March 25, 1991; or McDonnell Douglas Service Bulletin DC9-54-030, Revision 05, dated August 26, 1999, or Revision 06, dated November 11, 1999; are considered acceptable for compliance with the inspections required by paragraph (a) of this AD.
(b) For airplanes on which the modification specified in paragraph (e) of this AD has not been accomplished: Prior to the accumulation of 8,000 total flight hours or within 3,600 flight hours after the effective date of this AD, whichever occurs later, perform x-ray and eddy current inspections to detect cracks of the upper cap of the front spar of the left and right engine pylons, in accordance with McDonnell Douglas Service Bulletin DC9-54-030, Revision 06, dated November 11, 1999. Accomplishment of these inspections constitutes terminating action for the repetitive inspection requirements of paragraph (a) of this AD.
(c) If no crack is detected during any inspection required by paragraph (a) or (b) of this AD, repeat the inspections thereafter at intervals not to exceed 3,600 flight hours until the modification required by paragraph (e) of this AD is accomplished.
(d) If any crack is detected during any inspection required by paragraph (a) or (b) of this AD, prior to further flight, accomplish the modification specified in paragraph (e) of this AD.
(e) Except as provided by paragraph (d) of this AD, prior to the accumulation of 100,000 total landings, or within 6 months after the effective date of this AD, whichever occurs later, modify the upper cap of the front spar of the left and right engine pylons in accordance with McDonnell Douglas Service Bulletin DC9-54-030, Revision 06, dated November 11, 1999. Accomplishment of this modification constitutes terminating action for the requirements of this AD.
Note 3: Accomplishment of the modification of the upper cap of the front spar of the left and right engine pylons prior to the effective date of this AD in accordance with Douglas Service Bulletin 54-30, Revision 4, dated March 25, 1991, or McDonnell Douglas Service Bulletin DC9-54-030, Revision 5, dated August 26, 1999; is considered acceptable for compliance with the modification specified in paragraph (e) 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.
