Lower Fuselage Skin Panels

Effective Date - 11/12/1999
Recurring - N/A
Supersedes - N/A
Superseded by - N/A
Amendment 39-11353.
Docket 98-NM-367-AD.

Applicability: Model 727-100 and -100C series airplanes; line numbers 126, 130, 146, 153, 221, 287, 331, 339, 345, 355, 416, 516, 532, 540, 551, 555, 559, 575, 592, 594, 596, 599, 600, 604, 605, 615, 619, 625, 626, 628, 630, 631, 632, 635, 640, 641, 643, 645, 647, 658, 660, 686, 695, 700, 711, 712, 735, 748, 766, 768, 784, 797, 803, 806, 810, 812, 817, 821, 822, 824, 829, 854, 856, 857, 858, 861, and 869; 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 (b) 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.
Compliance: Required as indicated, unless accomplished previously.
To prevent degradation of the structural integrity of certain skin panels of the lower fuselage, which could result in loss of
airplane pressurization, accomplish the following:
(a) Within 20 years since original installation, or within 4 years after the effective date of this AD, whichever occurs later,  replace the skin panels of the lower fuselage between body station (BS) 950 and BS 1183 with non-bonded skin panels, in accordance with Part VI of the Accomplishment Instructions of Boeing Service Bulletin 727-53-0085, Revision 4, dated July 11, 1991.
Note 2: Accomplishment of the modification specified in Boeing Service Bulletin 727-53-0085, Revision 2, dated July 3, 1975, or Revision 3, dated September 28, 1989, is acceptable for compliance with the replacement required by paragraph (a) of this AD.
Note 3: Accomplishment of the modification specified in paragraph (a) of this AD constitutes terminating action for the  inspection requirements of AD 92-19-10, amendment 39-8368 (57 FR 47404, October 16, 1992) for those panels.
Alternative Methods of Compliance
(b) 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 Aircraft Certification Office (ACO), FAA, Transport Airplane Directorate. 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.
Note 4: Information concerning the existence of approved alternative methods of compliance with this AD, if any, may be  obtained from the Seattle ACO.
Special Flight Permits
(c) Special flight permits may be issued in accordance with sections 21.197 and 21.199 of the Federal Aviation Regulations (14 CFR 21.197 and 21.199) to operate the airplane to a location where the requirements of this AD can be accomplished.
Incorporation by Reference
(d) The replacement shall be done in accordance with Boeing Service Bulletin 727-53-0085, Revision 4, dated July 11, 1991. This incorporation by reference was approved by the Director of the Federal Register in accordance with 5 U.S.C. 552(a) and 1 CFR part 51. Copies may be obtained from Boeing Commercial Airplane Group, P.O. Box 3707, Seattle, Washington 98124-2207. Copies may be inspected at the FAA, Transport Airplane Directorate, 1601 Lind Avenue, SW., Renton, Washington; or at the Office of the Federal Register, 800 North Capitol Street, NW., suite 700, Washington, DC.
(e) This amendment becomes effective on November 12, 1999.
Issued in Renton, Washington, on September 28, 1999. D.L. Riggin, Acting Manager, Transport Airplane Directorate, Aircraft Certification  Service.