Airworthiness Directive · Amendment 39-12013 · Boeing Model 707, 727C, and 727-100C Series Airplanes
Boeing Model 707, 727C, and 727-100C Series Airplanes
Model 707, 727C, and 727-100C series airplanes; as listed in Boeing Service Bulletins 2999, Revision 3, dated January 12, 1972, and 727-52-79, Revision 4, dated June 19, 1981; certificated in any category.
Note 1: This AD applies to each airplane identified in the preceding applicability provision, regardless of whether it has been 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 (g)(1) 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 Boeing Model 707, 727C, and 727-100C series airplanes, that currently requires repetitive inspections to detect cracking of the main cargo door skin and frames, and repair, if necessary. The existing AD also provides optional terminating modifications. This amendment requires follow-on repetitive inspections of repaired or modified areas for certain airplanes. This amendment is prompted by reports of cracking and/or tearing of the main cargo door outer skin and subsequent failure of the door frame. The actions specified by this AD are intended to detect and correct such cracking and/or tearing, which could result in failure of the door frame and consequent rapid decompression of the airplane.
To detect and correct cracking of the main cargo door skin and frames, which could result in failure of the door frame, and consequent rapid decompression of the airplane, accomplish the following:
Note 2: For the purposes of this AD, a detailed visual inspection is defined as: “An intensive visual examination of a specific structural area, system, installation, or assembly to detect damage, failure, or irregularity. Available lighting is normally supplemented with a direct source of good lighting at intensity deemed appropriate by the inspector. Inspection aids such as mirror, magnifying lenses, etc., may be used. Surface cleaning and elaborate access procedures may be required.”
(a) Within 500 landings after March 3, 1983 (the effective date of AD 83-02-09, amendment 39-4549), or prior to the accumulation of 25,000 total landings after March 3, 1983, whichever occurs later: Perform an inspection (detailed visual, eddy current, or X-ray) to detect cracks of the main cargo door outer skin and frames between body stations (BS) 505 and 595, from the lower edge of the door hinge a minimum of 6 inches down, and 6 inches above, and 3 inches below the center line of stringer 10, in accordance with Boeing Service Bulletin 2999, Revision 3, dated January 12, 1972, or Revision 4, dated January 31, 1991 (for Model 707 series airplanes); or Boeing Service Bulletin 727-52-79, Revision 4, dated June 19, 1981, or Boeing Service Bulletin 727-52-79, Revision 5, dated June 17, 1983, or Boeing Service Bulletin 727-52A0079, Revision 6, dated January 11, 1990 (for Model 727 series airplanes); as applicable.
(b) Repeat the inspection required by paragraph (a) of this AD at the times specified in paragraph (b)(1), (b)(2) or (b)(3) of this AD; as applicable; until accomplishment of the modification required by paragraph (d) of this AD.
(1) Repeat the detailed visual inspection at intervals not to exceed 500 landings.
(2) Repeat the eddy current inspection at intervals not to exceed 750 landings.
(3) Repeat the X-ray inspection at intervals not to exceed 1,000 landings.
(c) If any cracking is detected during any inspection required by paragraph (a) or (b) of this AD: Prior to further flight, repair any cracks detected in accordance with Boeing Service Bulletin 2999, Revision 3, dated January 12, 1972, or Revision 4, dated January 31, 1991 (for Model 707 series airplanes); or Boeing Service Bulletin 727-52-79, Revision 4, dated June 19, 1981, or Boeing Service Bulletin 727-52-79, Revision 5, dated June 17, 1983, or Boeing Service Bulletin 727-52A0079, Revision 6, dated January 11, 1990 (for Model 727 series airplanes); as applicable.
(d) Modification of the main cargo door in accordance with Part II, Option 1 or Option 2, as applicable, of the Accomplishment Instructions of Boeing Service Bulletin 2999, Revision 3, dated January 12, 1972, or Revision 4, dated January 31, 1991 (for Model 707 series airplanes); or Boeing Service Bulletin 727-52-79, Revision 4, dated June 19, 1981, or Boeing Service Bulletin 727-52-79, Revision 5, dated June 17, 1983, or Boeing Service Bulletin 727-52A0079, Revision 6, dated January 11, 1990 (for Model 727 series airplanes); as applicable; constitutes terminating action for the requirements of paragraphs (a) and (b) of this AD.
(e) For Model 727 series airplanes: Within 27,000 flight cycles after accomplishment of the repair specified in paragraph (c) of this AD, and/or the modification specified in paragraph (d) of this AD, as applicable; or within 1,000 flight cycles after the effective date of this AD; whichever occurs later; accomplish the requirements of paragraph (e)(1) or (e)(2) of this AD, as applicable.
(1) For airplanes that have accomplished the modification specified in Part II of the Accomplishment Instructions of Boeing Service Bulletin 727-52-79, Revision 4, dated June 19, 1981, or Revision 5, dated June 17, 1983; or in Part II, Option 1, of the Accomplishment Instructions of Boeing Service Bulletin 727-52A0079, Revision 6, dated January 11, 1990: Perform a detailed visual and eddy current inspection of the modified area and/or any repaired area to detect cracks, in accordance with the service bulletin. Repeat the inspections at intervals not to exceed 3,800 flight cycles.
(2) For airplanes that have accomplished the modification specified in Part II, Option 2 of the Accomplishment Instructions of Boeing Service Bulletin 727-52A0079, Revision 6, dated January 11, 1990: Perform an internal and external detailed visual inspection of the modified area to detect cracks in accordance with the service bulletin. Repeat the inspection at intervals not to exceed 3,800 flight cycles.
(f) If any cracking is detected during any inspection required by paragraph (e)(1) or (e)(2) of this AD: Prior to further flight, repair any cracks detected in accordance with a method approved by the Manager, Seattle Aircraft Certification Office (ACO), FAA; or in accordance with data meeting the type certification basis of the airplane approved by a Boeing Company Designated Engineering Representative who has been authorized by the Manager, Seattle ACO, to make such findings. For a repair method to be approved by the Manager, Seattle ACO, as required by this paragraph, the Manager's approval letter must specifically reference this AD.
(g)(1) An alternative method of compliance or adjustment of the compliance time that provides an acceptable level of safety may be used if approved by the Manager, Seattle ACO. Operators shall submit their requests through an appropriate FAA Principal Maintenance Inspector, who may add comments and then send it to the Manager, Seattle ACO.
(2) Alternative methods of compliance approved previously in accordance with AD 83-02-09, amendment 39-4549, are approved as alternative methods of compliance with this AD.
Note 3: Information concerning the existence of approved alternative methods of compliance with this AD, if any, may be obtained from the Seattle ACO.
Note 4: Incorporation of the Boeing Model 707-720 Supplemental Structural Inspection Document (SSID) into the operator's approved airplane maintenance program constitutes an approved alternative method of compliance for Model 707 and 720 series airplanes.
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.
Aircraft
