2009-07-11: Fuselage skin

2009-07-11 Boeing: Amendment 39-15870. Docket No. FAA-2008-0412; Directorate Identifier 2007-NM-346-AD. \n\nEffective Date \n\n\t(a) This AD becomes effective May 14, 2009. \n\nAffected ADs \n\n\t(b) This AD supersedes AD 2004-22-05. \n\nApplicability \n\n\t(c) This AD applies to all Boeing Model 737-300, -400, and -500 series airplanes, certificated in any category. \n\nUnsafe Condition \n\n\t(d) This AD results from a report of an 18-inch crack found in the fuselage skin area under the blade seals of the nose cap of the dorsal fin due to previous wear damage, and additional reports of fuselage skin wear. We are issuing this AD to prevent discrepancies of the fuselage skin, which could result in fatigue cracking due to cabin pressurization and consequent rapid in-flight decompression of the airplane fuselage. \n\nCompliance \n\n\t(e) You are responsible for having the actions required by this AD performed within the compliance times specified, unless the actions have already been done.Restatement of Requirements of AD 2004-22-05 \n\nRepetitive Detailed Inspections \n\n\t(f) For airplanes specified in either paragraph (f)(1), (f)(2), (f)(3), or (f)(4) of this AD: Accomplish a detailed inspection for discrepancies (wear or cracking) of the fuselage skin under the dorsal fin assembly by doing all the actions specified in Boeing Message Number 1-QXO35, dated October 13, 2004. Repeat the inspection thereafter at intervals not to exceed 9,000 flight cycles. Accomplishing all of the applicable actions specified in paragraph (i) of this AD terminates the repetitive inspections required by this paragraph. \n\n\tNote 1: For the purposes of this AD, a detailed inspection is: "An intensive examination of a specific item, installation, or assembly to detect damage, failure, or irregularity. Available lighting is normally supplemented with a direct source of good lighting at an intensity deemed appropriate. Inspection aids such as mirror, magnifying lenses, etc., may be necessary. Surface cleaning and elaborate procedures may be required.'' \n\n\t(1) For airplanes with line numbers 1001 through 2828 inclusive that have not been inspected as of November 12, 2004 (the effective date of AD 2004-22-05), in accordance with Boeing Service Bulletin 737-55-1057, dated December 12, 1996; or Revision 1, dated July 22, 1999: Inspect before the accumulation of 18,000 total flight cycles, or within 90 days after November 12, 2004, whichever is later. \n\t(2) For airplanes with line numbers 2829 through 3132 inclusive that are not included in the effectivity of Boeing Service Bulletin 737-55-1057, dated December 12, 1996; or Revision 1, dated July 22, 1999: Inspect before the accumulation of 18,000 total flight cycles, or within 90 days after November 12, 2004, whichever is later. \n\t(3) For airplanes with line numbers 1001 through 2828 inclusive that have been inspected, but not repaired or modified as of November 12, 2004, in accordance with Boeing Service Bulletin 737- 55-1057, dated December 12, 1996; or Revision 1, dated July 22, 1999: Inspect within 9,000 flight cycles after accomplishing the inspection, or within 90 days after November 12, 2004, whichever is later. \n\t(4) For airplanes with line numbers 1001 through 2828 inclusive that have been inspected and repaired or modified as of November 12, 2004, in accordance with Boeing Service Bulletin 737-55-1057, dated December 12, 1996; or Revision 1, dated July 22, 1999: Inspect within 18,000 flight cycles after accomplishing the repair or modification, or within 90 days after November 12, 2004, whichever is later; and if a repair doubler is installed, before further flight, inspect the repair doubler for discrepancies (wear or cracking). \n\n\tNote 2: Boeing Message Number 1-QXO35, dated October 13, 2004, references Part I of Boeing Service Bulletin 737-55-1057, Revision 1, dated July 22, 1999, as an additional source of service information for accomplishing the actions required by paragraph (f) of this AD. \n\nRepair \n\n\t(g) If any discrepancy (wear or cracking) is found during any inspection required by paragraph (f) of this AD, before further flight, repair in accordance with a method approved by the Manager, Seattle Aircraft Certification Office (ACO), FAA; or using a method approved in accordance with the procedures specified in paragraph (1) of this AD. \n\nReporting Not Required \n\n\t(h) Although Boeing Message Number 1-QXO35, dated October 13, 2004, specifies to report any fuselage skin cracking found during the detailed inspections, this AD does not include that requirement. \n\nNew Requirements of This AD \n\nNew Inspections and Other Specified and Corrective Actions \n\n\t(i) At the applicable compliance times specified in paragraph 1.E. of Boeing Alert Service Bulletin 737-53A1266, dated August 30, 2007, except as provided by paragraph (j) of this AD: Do a detailed inspection for any chafing (abrasion) or crack in the fuselage skin of the dorsal fin landing and abrasion resistant coating, do a detailed inspection for damage to dorsal fin seals, attach clip, and seal retainers, and do all the applicable other specified and corrective actions, by accomplishing all of the applicable actions specified in the Accomplishment Instructions of Boeing Alert Service Bulletin 737-53A1266, dated August 30, 2007, except as provided by paragraph (k) of this AD. Accomplishing all of the applicable actions specified in this paragraph terminates the repetitive inspections required by paragraph (f) of this AD. \n\nException to Compliance Times \n\n\t(j) Where Boeing Alert Service Bulletin 737-53A1266, dated August 30, 2007, specifies counting the compliance time from "* * * the date on the service bulletin,'' this AD requires counting the compliance time from the effective date of this AD. \n\nException to Corrective Actions \n\n\t(k) If any damage is found aft of body station 908 during any inspection required by this AD, and Boeing Alert Service Bulletin 737-53A1266,dated August 30, 2007, specifies to contact Boeing for appropriate action: Before further flight, repair the fuselage skin using a method approved in accordance with the procedures specified in paragraph (l) of this AD. \n\nAlternative Methods of Compliance (AMOCs) \n\n\t(l)(1) The Manager, Seattle Aircraft Certification Office, Transport Airplane Directorate, FAA, has the authority to approve AMOCs for this AD, if requested in accordance with the procedures found in 14 CFR 39.19. \n\t(2) To request a different method of compliance or a different compliance time for this AD, follow the procedures in 14 CFR 39.19. Before using any approved AMOC on any airplane to which the AMOC applies, notify your appropriate principal inspector (PI) in the FAA Flight Standards District Office (FSDO), or lacking a PI, your local FSDO. \n\t(3) An AMOC that provides an acceptable level of safety may be used for any repair required by this AD, if it is approved by an Authorized Representative for the BoeingCommercial Airplanes Delegation Option Authorization Organization who has been authorized by the Manager, Seattle ACO, to make those findings. For a repair method to be approved, the repair must meet the certification basis of the airplane, and the approval must specifically refer to this AD. \n\t(4) AMOCs approved previously in accordance with AD 2004-22-05 are approved as AMOCs for the corresponding provisions of paragraphs (f) and (g) of this AD. \n\nMaterial Incorporated by Reference \n\n\t(m) You must use Boeing Alert Service Bulletin 737-53A1266, dated August 30, 2007; and Boeing Message Number 1-QXO35, dated October 13, 2004; as applicable; to do the actions required by this AD, unless the AD specifies otherwise. \n\t(1) The Director of the Federal Register approved the incorporation by reference of Boeing Alert Service Bulletin 737- 53A1266, dated August 30, 2007, under 5 U.S.C. 552(a) and 1 CFR part 51. \n\t(2) The Director of the Federal Register previously approved the incorporation by reference of Boeing Message Number 1-QXO35, dated October 13, 2004, on November 12, 2004 (69 FR 62567, October 27, 2004). \n\t(3) For service information identified in this AD, contact Boeing Commercial Airplanes, Attention: Data & Services Management, P. O. Box 3707, MC 2H-65, Seattle, Washington 98124-2207; telephone 206-544-5000, extension 1, fax 206-766-5680; e-mail [email protected]; Internet https://www.myboeingfleet.com. \n\t(4) You may review copies of the service information at the FAA, Transport Airplane Directorate, 1601 Lind Avenue, SW., Renton, Washington. For information on the availability of this material at the FAA, call 425-227-1221 or 425-227-1152. \n\t(5) You may also review copies of the service information that is incorporated by reference at the National Archives and Records Administration (NARA). For information on the availability of this material at NARA, call 202-741-6030, or go to: http:// www.archives.gov/federal_register/code_of_federal_regulations/ ibr_locations.html.