2009-14-02: Vertical stabilizer seal and fuselage skin

2009-14-02 Boeing: Amendment 39-15951. Docket No. FAA-2008-1071; Directorate Identifier 2008-NM-093-AD. \n\nEffective Date \n\n\t(a) This AD becomes effective August 3, 2009. \n\nAffected ADs \n\n\t(b) This AD supersedes AD 2002-26-15. \n\nApplicability \n\n\t(c) This AD applies to Boeing Model 747-100, 747-100B, 747-100B SUD, 747-200B, 747-200C, 747-200F, 747-300, 747-400, 747-400D, 747- 400F, 747SR, and 747SP series airplanes, certificated in any category, as identified in Boeing Alert Service Bulletin 747- 53A2478, Revision 1, dated March 27, 2008. \n\nUnsafe Condition \n\n\t(d) This AD results from reports of skin wear damage on airplanes with fewer than 8,000 total flight cycles. In addition, there have been three reports of skin wear damage on airplanes on which Boeing Material Specifications (BMS) 10-86 Teflon-filled coating was applied (terminating action per AD 2002-26-15). We are issuing this AD to detect and correct wear damage and cracks of the fuselage skin in the interfacearea of the vertical stabilizer seal and fuselage skin in sections 46 and 48, which could cause in-flight depressurization of the airplane. \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. \n\nRequirements of AD 2002-26-15 \n\nInspections for Damage/Corrective Actions \n\n\t(f) For airplanes identified in Boeing Alert Service Bulletin 747-53A2478, dated February 7, 2002: Prior to the accumulation of 15,000 total flight cycles, or within 1,200 flight cycles after February 10, 2003 (the effective date of AD 2002-26-15), whichever occurs later, perform a detailed inspection to detect evidence of wear damage of the fuselage skin at the interface area of the vertical stabilizer seal and fuselage skin, per Boeing Alert Service Bulletin 747-53A2478, dated February 7, 2002. \n\t(1) If no wear damage of the fuselage skin is detected or any existing blendout is within the structural repair manual (SRM) allowable damage limits: Repeat the detailed inspection at intervals not to exceed 6,000 flight cycles. \n\t(2) If any wear damage of the fuselage skin is detected or any existing blendout exceeds the allowable damage limits specified in the SRM: Before further flight, repair the vertical stabilizer seal interface and refinish the skin with BMS 10-86 Teflon-filled coating, per Boeing Alert Service Bulletin 747-53A2478, dated February 7, 2002. Accomplishment of the repair and refinishing is terminating action for the repetitive inspections required by paragraph (f)(1) of this AD. \n\n\tNote 1: For the purposes of this AD, a detailed 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.'' \n\nOptional Terminating Action for Paragraph (f) of This AD \n\n\t(g) Refinishing the fuselage skin with BMS 10-86 Teflon-filled coating, prior to the effective date of this AD, per Boeing Alert Service Bulletin 747-53A2478, dated February 7, 2002, terminates the repetitive inspections required by paragraph (f)(1) of this AD. \n\nPreviously Accomplished Inspections and Terminating Action \n\n\t(h) For airplanes identified in Boeing Alert Service Bulletin 747-53A2478, dated February 7, 2002: Inspections and terminating action done before February 10, 2003, per Boeing Service Bulletin 747-53-2192, dated July 21, 1981, are acceptable for compliance with the corresponding actions required by paragraph (f) of this AD, provided BMS 10-86 Teflon-filled coating was used, and the new allowable damage limits specified in Boeing Alert Service Bulletin 747-53A2478, dated February 7, 2002, are met. \n\nNew Requirements of This AD \n\nNew Repetitive Inspections \n\n\t(i) Except as provided by paragraph (j) of this AD: At the applicable times specified in Table 1 of this AD, do the actions specified in paragraphs (i)(1) and (i)(2) of this AD, as applicable. Accomplishing the initial inspection specified in paragraph (i) terminates the requirements of paragraph (f) of this AD. \n\t(1) For all airplanes: Do the actions specified in paragraphs (i)(1)(i) and (i)(1)(ii) of this AD, as applicable. \n\t(i) Do repetitive external detailed inspections for wear damage and cracks of the fuselage skin in the interface area of the vertical stabilizer seal and fuselage skin, in accordance with the Accomplishment Instructions of Boeing Alert Service Bulletin 747- 53A2478, Revision 1, dated March 27, 2008. \n\t(ii) Where a skin repair doubler is present in the interface area of the vertical stabilizer seal and fuselage skin, do a detailed inspection for wear damage and cracks of the surface ofthe repair doubler. \n\t(2) For airplanes that have reduced skin thickness in section 46 due to blending without reinforcement: Do repetitive external detailed inspections or high frequency eddy (HFEC) current inspections for cracks of the blended area of the fuselage skin, in accordance with the Accomplishment Instructions of Boeing Alert Service Bulletin 747- 53A2478, Revision 1, dated March 27, 2008. \n\n\tTable 1--Compliance Times\n\n\n\n\n\nCompliance time (whichever occurs later)\n\nAction\nThreshold\nGrace Period\nRepeat Interval (Not to Exceed)\nFor actions required by paragraph (i)(1) of this AD\nPrior to the accumulation of 20,000 total flight hours since the date of issuance of the original airworthiness certificate or the date of issuance of the original export certificate of airworthiness, or within 7,500 flight hours after the last inspection of this AD, whichever occurs later\nWithin 6,000 flight hours after the effective date of this AD\n7,500 flight hours\nFor actions required by paragraph (i)(2) of this AD\nPrior to the accumulation of 20,000 total flight cycles since the date of issuance of the original airworthiness certificate or the date of issuance of the original export certificate of airworthiness, or within 6,000 flight cycles after the initial blend, whichever occurs later\nWithin 1,000 flight cycles after the effective date of this AD\n1,200 flight cycles for external detailed inspection, or 6,000 flight cycles for HFEC inspection\n\nException to the Repetitive Inspections \n\n\t(j) If corrosion-resistant steel rubstrips are installed in the interface area of the vertical stabilizer seal and fuselage skin: Within the applicable compliance times specified in paragraph (i) of this AD, inspect the fuselage skin using a method approved in accordance with the procedures specified in paragraph (m) of this AD. \n\nFor No Wear Damage or Cracks Found: Apply Teflon \n\n\t(k) If no wear damage or crack is found in the fuselage skin (or skin repair doubler) during any inspection required by paragraph (i) of this AD: Before further flight, apply Boeing Material Specifications (BMS) 10-86 Teflon-filled coating in accordance with the Accomplishment Instructions of Boeing Alert Service Bulletin 747-53A2478, Revision 1, dated March 27, 2008. \n\nFor Any Wear Damage or Crack Found: Applicable Corrective Actions \n\n\t(l) If any wear damage or crack is found in the fuselage skin (or skin repair doubler) during any inspections required by paragraph (i) of this AD: Before further flight, after the inspection required by paragraph (i), do the actions specified in paragraphs (l)(1), (l)(2), and (l)(3) of this AD, in accordance with the Accomplishment Instructions of Boeing Alert Service Bulletin 747-53A2478, Revision 1, dated March 27, 2008. \n\t(1) Measure the depth of the wear and record the location. \n\t(2) Repair any wear damage and any crack. \n\t(3) Apply BMS 10-86 Teflon-filled coating. \n\nAlternative Methods of Compliance (AMOCs) \n\n\t(m)(1) The Manager, Seattle Aircraft Certification Office (ACO), FAA, ATTN: Ivan Li, Aerospace Engineer, Airframe Branch, ANM-120S, FAA, Seattle ACO, 1601 Lind Avenue, SW., Renton, Washington 98057- 3356; telephone (425) 917-6437; fax (425) 917-6590; has the authority to approve AMOCs for this AD, if requested using 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 Boeing Commercial 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\nMaterial Incorporated by Reference \n\n\t(n) You must use Boeing Alert Service Bulletin 747-53A2478, dated February 7, 2002; and Boeing Alert Service Bulletin 747- 53A2478, Revision 1, dated March 27, 2008; 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 747- 53A2478, Revision 1, dated March 27, 2008, 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 Alert Service Bulletin 747- 53A2478, dated February 7, 2002, on February 10, 2003 (68 FR 476, January 6, 2003). \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 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.