AD 2004-25-05 Airworthiness Directives; Boeing Model 747-100, 747-100B, 747-100B SUD, 747-200B, 747-200C, 747-200F, 747-300, 747SP, and 747SR Series Airplanes

This AD applies to Boeing 747-100, 747-100B, 747-100B SUD, 747-200B, 747-200C, 747-200F, 747-300, 747SP, and 747SR series airplanes; as listed in Boeing Alert Service Bulletin (ASB) 747-54A2224, dated September 30, 2004; certificated in any category.

You are responsible for having the actions required by this AD performed within the compliance times specified, unless the actions have already been done. Detailed and High Frequency Eddy Current (HFEC) Inspections (e) Within 90 days after the effective date of this AD, perform detailed and HFEC inspections to detect any cracks or fractures of the front spar chord assembly for struts Number 1 through 4 inclusive, in accordance with Boeing ASB 747-54A2224, dated September 30, 2004. (f) Accomplishment of the detailed and HFEC inspections in accordance with Boeing 747 Fleet Team Digest 747-FTD-54-04002, dated April 15, 2004, May 4, 2004, June 1, 2004, July 12, 2004, or July 28, 2004; or Boeing Message 1-C6ELC (Service Request ID No.: 218724992), dated April 14, 2004; before the effective date of this AD, is considered acceptable for compliance with the requirements of paragraph (e) of this AD. Repetitive Inspections (g) For airplanes on which no crack or fracture is detected: At the times specified in Table 1—Repetitive Intervals of this AD, perform the detailed and HFEC inspections required by paragraph (e) of this AD at the intervals specified in Table 1. Table 1.—Repetitive Intervals For Airplanes identified in Boeing ASB 747-54A2224, dated September 30, 2004, as— At intervals not to exceed— Group 1 1,000 flight cycles or 18 months, whichever occurs first. Group 2 and Group 3 1,200 flight cycles or 18 months, whichever occurs first. Group 4 and Group 6 1,500 flight cycles or 18 months, whichever occurs first. Group 5 2,000 flight cycles or 18 months, whichever occurs first. Corrective Action (h) If any crack or fracture is found during any inspection required by this AD, and the bulletin specifies contacting Boeing for appropriate action: Before further flight, repair the crack or fracture according to 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 (DER) who has been authorized by the Manager, Seattle ACO, to make those findings. For a repair method to be approved, the approval must specifically reference this AD. Alternative Methods of Compliance (AMOCs) (i)(1) The Manager, Seattle ACO, FAA, has the authority to approve AMOCs for this AD, if requested in accordance with the procedures found in 14 CFR 39.19. (2) An AMOC that provides an acceptable level of safety may be used for any repair required by this AD, if it is approved by a Boeing Company DER who has been authorized by the Manager, Seattle ACO, to make those findings. For a repair method to be approved, the approval must specifically refer to this AD. Material Incorporated by Reference (j) You must use Boeing Alert Service Bulletin 747-54A2224, dated September 30, 2004, to perform the actions that are required by this AD, unless the AD specifies otherwise. The Director of the Federal Register approves the incorporation by reference of this document in accordance with 5 U.S.C. 552(a) and 1 CFR part 51. For copies of the service information, contact Boeing Commercial Airplanes, PO Box 3707, Seattle, Washington 98124-2207. You can review copies at the Docket Management Facility, U.S. Department of Transportation, 400 Seventh Street SW., room PL-401, Nassif Building, Washington, DC; or 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. Issued in Renton, Washington, on November 30, 2004. Ali Bahrami, Manager, Transport Airplane Directorate, Aircraft Certification Service. [FR Doc. 04-26793 Filed 12-8-04; 8:45 am] BILLING CODE 4910-13-P

This AD was prompted by a report of a fractured front spar chord assembly for strut No. 3, which resulted in the loss of the strut upper link load path. The FAA is issuing this AD to prevent loss of the strut upper link load path and consequent fracture of the diagonal brace, which could result in in-flight separation of the strut and engine.