2002-23-15: Lower lobe panel

2002-23-15 Boeing: Amendment 39-12959. Docket 2002-NM-270-AD. \n\n\tApplicability: Model 747-100, -200B, -200C, -200F, -300, -400, - 400F, and 747SR series airplanes; equipped with a main deck side cargo door manufactured by Boeing; certificated in any category. \n\n\tNote 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 (d) 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. \n\n\tTo find and fix cracking of the lower lobe panel of the fuselage skin of the aft cargo bay, which could lead to reduced structural integrity of the side cargo door cutout of the main deck, and result in rapid depressurization of the airplane, accomplish the following: \n\nRepetitive Inspections \n\n\t(a) Do either an internal detailed or eddy current inspection to find cracking of the lower lobe panel of the fuselage skin of the aft cargo bay, below stringer 34L, from Station (STA) 1640 through 1740 inclusive, per Boeing Alert Service Bulletin 747-53A2487, Revision 1, dated October 31, 2002. Do the initial inspection at the time shown in paragraph (a)(1) or (a)(2) of this AD, as applicable. If the initial inspection was a detailed inspection, repeat that inspection at least every 50 flight cycles; if the initial inspection was an eddy current inspection, repeat that inspection at least every 250 flight cycles;as applicable. Although the service bulletin references a reporting requirement in paragraph 1.D., such reporting is not required by this AD. \n\n\tNote 2: 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\n\t(1) For airplanes on which the main deck side cargo door (MDSCD) was installed after the date of manufacture of the airplane: Do the inspection within 10,000 flight cycles after installation of the MDSCD, or within 90 days after the effective date of this AD, whichever is later. \n\n\t(2) For airplanes on which the MDSCD was installed before the date of manufacture of the airplane: Do the inspection prior to the accumulation of 15,000 total flight cycles on the airplane, or within 90 days after the effective date of this AD, whichever is later. \n\n\t(b) Inspections done before the effective date of this AD per Boeing Alert Service Bulletin 747-53A2487, dated October 24, 2000; are considered acceptable for compliance with paragraph (a) of this AD. \n\nRepair \n\n\t(c) If any crack is found during any inspection required by paragraph (a) of this AD: Before further flight, repair per a method approved by the Manager, Seattle Aircraft Certification Office (ACO), FAA; or per 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. \n\nAlternative Methods of Compliance \n\n\t(d) 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. \n\n\tNote 3: Information concerning the existence of approved alternative methods of compliance with this AD, if any, may be obtained from the Seattle ACO. \n\nSpecial Flight Permits \n\n\t(e) 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. \n\nIncorporation by Reference \n\n\t(f) Unless otherwise provided by this AD, the actions shall be done in accordance with Boeing Alert Service Bulletin 747-53A2487, Revision 1, dated October 31, 2002. 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, PO 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. \n\nEffective Date \n\n\t(g) This amendment becomes effective on December 11, 2002.