AD 2004-06-12 Airworthiness Directives; Boeing Model 747-400F Series Airplanes

Models named: 747-400F series. Read the applicability below — it usually turns on serial or part numbers too.

Model 747-400F series airplanes, having line numbers 968 through 1286 inclusive, certificated in any category.

Required as indicated, unless accomplished previously. To detect and correct fatigue cracks in the fuselage skin and frame shear tie assemblies, which could propagate and result in possible in-flight decompression of the airplane, accomplish the following: Service Bulletin Reference (a) The term “service bulletin,” as used in this AD, means the Accomplishment Instructions of Boeing Special Attention Service Bulletin 747-53-2480, dated March 28, 2002. Compliance Time (b) At the later compliance time specified in paragraphs (b)(1) and (b)(2) of this AD, do the inspections specified in paragraph (c) of this AD. (1) Within 6,000 flight cycles after the date of issuance of the original Airworthiness Certificate or date of issuance of the Export Certificate of Airworthiness, whichever comes first. (2) Within 3,000 flight cycles after the effective date of this AD. Repetitive Inspections (c) Perform both inspections of the external fuselage skin as shown in Table 1 of this AD, per the service bulletin. Repeat the inspections thereafter at intervals not to exceed 3,000 flight cycles. Table 1.—Inspection Requirements Type of inspection Area to inspect (1) Detailed Inspect the skin surface for cracks initiating from the shear tie fasteners (14 locations on each side) common to the body station 800 frame between stringers S-13 and S-15 on both the left and right sides of the airplane. (2) General visual Inspect the skin surface at all fastener locations for cracks between body stations 780 to 800 and stringers S-13 through S-15 on both the left and right sides of the airplane. Note 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.” Note 2: For the purposes of this AD, a general visual inspection is defined as: “A visual examination of an interior or exterior area, installation, or assembly to detect obvious damage, failure, or irregularity. This level of inspection is made from within touching distance unless otherwise specified. A mirror may be necessary to enhance visual access to all exposed surfaces in the inspection area. This level of inspection is made under normally available lighting conditions such as daylight, hangar lighting, flashlight, or droplight and may require removal or opening of access panels or doors. Stands, ladders, or platforms may be required to gain proximity to the area being checked.” Crack Findings: Inspections and Repair (d) If any crack is found during any inspection required by paragraph (c) of this AD, before further flight, do the actions specified in paragraphs (d)(1) and (d)(2) of this AD. (1) Perform inspections of the affected area to determine the extent of the crack using the following applicable inspection methods, per the service bulletin: detailed inspection; open-hole high frequency eddy current (HFEC) inspection; surface HFEC inspection; and dye penetrant inspection. (2) Repair any crack per the service bulletin. Where the service bulletin specifies contacting Boeing for an alternate repair method: 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 DER who has been authorized by the Manager, Seattle ACO, to make such findings. Terminating Action for Repaired Area (e) Accomplishment of the repair per paragraph (d)(2) of this AD ends the repetitive inspection requirements of paragraph (c) of this AD for that repaired area only. Alternative Methods of Compliance (f) In accordance with 14 CFR 39.19, the Manager, Seattle ACO, FAA, is authorized to approve alternative methods of compliance (AMOCs) for this AD. Incorporation by Reference (g) Unless otherwise specified in this AD, the actions shall be done in accordance with Boeing Special Attention Service Bulletin 747-53-2480, dated March 28, 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 Airplanes, 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. Effective Date (h) This amendment becomes effective on April 30, 2004. Issued in Renton, Washington, on March 16, 2004. Kevin M. Mullin, Acting Manager, Transport Airplane Directorate, Aircraft Certification Service. [FR Doc. 04-6579 Filed 3-25-04; 8:45 am] BILLING CODE 4910-13-P