AD 2007-01-15 Airworthiness Directives; Boeing Model 747-100, 747-100B, 747-100B SUD, 747-200B, 747-200C, 747-200F, 747-300, 747SR, and 747SP Series Airplanes Equipped with General Electric CF6-45 or -50 Series Engines, or Equipped with Pratt & Whitney JT9D-3 or -7 (Excluding -70) Series Engines

Models named: 747-100, 747-100B, 747-100B SUD, 747-200B, 747-200C, 747-200F, 747-300, 747SR, 747SP series. Read the applicability below — it usually turns on serial or part numbers too.

This AD applies to Boeing Model 747-100, 747-100B, 747-100B SUD, 747-200B, 747-200C, 747-200F, 747-300, 747SR, and 747SP series airplanes, certificated in any category, as identified in Boeing Alert Service Bulletin 747-54A2224, Revision 1, dated November 16, 2006.

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 2004-25-05 Aft Side Detailed and High Frequency Eddy Current (HFEC) Inspections With New Service Information (f) Within 90 days after December 27, 2004 (the effective date of AD 2004-25-05), perform detailed and HFEC inspections to detect any cracks or fractures of the front spar chord assembly for strut numbers 1 through 4 inclusive, in accordance with Boeing Alert Service Bulletin 747-54A2224, dated September 30, 2004; or in accordance with Part 1—Aft Side Inspection of the Accomplishment Instructions of Boeing Alert Service Bulletin 747-54A2224, Revision 1, dated November 16, 2006. As of the effective date of this AD, only Part 1—Aft Side Inspection of the Accomplishment Instructions of Revision 1 of the service bulletin may be used. (g) 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 December 27, 2004, is considered acceptable for compliance with the requirements of paragraph (f) of this AD. Repetitive Inspections (h) For airplanes on which no crack or fracture is detected during the inspections required by paragraph (f) of this AD: At the applicable times specified in Table 1—Repetitive Intervals of this AD, repeat the detailed and HFEC inspections required by paragraph (f) of this AD. Table 1.—Repetitive Intervals For airplanes identified in Boeing Alert Service Bulletin 747-54A2224, dated September 30, 2004; or Revision 1, dated November 16, 2006; as— Repeat the inspections 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 (i) If any crack or fracture is found during any inspection required by paragraphs (f) and (h) of 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 using a method approved in accordance with the procedures specified in paragraph (m) of this AD. For a repair method to be approved, the approval must specifically reference this AD. New Requirements of This Ad Forward Side Detailed and HFEC Inspections (j) Within 90 days after the effective date of this AD, do detailed and HFEC inspections for any cracks or fracture of the front spar chord assembly for strut numbers 1, 2, 3, and 4, in accordance with Part 2—Forward Side Inspection of the Accomplishment Instructions of Boeing Alert Service Bulletin 747-54A2224, Revision 1, dated November 16, 2006. If no crack or fracture is found, repeat the inspections thereafter at the applicable interval specified in Table 1 of this AD. Corrective Action for Forward Side Inspection (k) If any crack or fracture is found during any inspection required by paragraph (j) of this AD, and Boeing Alert Service Bulletin 747-54A2224, Revision 1, dated November 16, 2006, specifies to contact Boeing for appropriate action: Before further flight, repair the crack or fracture using a method approved in accordance with the procedures specified in paragraph (m) of this AD. Credit for Inspections Done According to Boeing 747 Fleet Team Digest (l) Detailed and HFEC inspections done before the effective date of this AD in accordance with Boeing 747 Fleet Team Digest 747-FTD-54-06002, dated June 29, 2006; or October 16, 2006; are acceptable for compliance with the initial inspection required by paragraph (j) of this AD. Alternative Methods of Compliance (AMOCs) (m)(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) Before using any AMOC approved in accordance with § 39.19 on any airplane to which the AMOC applies, notify the appropriate principal inspector in the FAA Flight Standards Certificate Holding District Office. (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. Material Incorporated by Reference (n) You must use Boeing Alert Service Bulletin 747-54A2224, dated September 30, 2004; and Boeing Alert Service Bulletin 747-54A2224, Revision 1, dated November 16, 2006; as applicable; to perform the actions that are required by this AD, unless the AD specifies otherwise. (1) The Director of the Federal Register approved the incorporation by reference of Boeing Alert Service Bulletin 747-54A2224, Revision 1, dated November 16, 2006, in accordance with 5 U.S.C. 552(a) and 1 CFR part 51. (2) On December 27, 2004 (69 FR 71349, December 9, 2004), the Director of the Federal Register approved the incorporation by reference of Boeing Alert Service Bulletin 747-54A2224, dated September 30, 2004. (3) Contact Boeing Commercial Airplanes, P.O. Box 3707, Seattle, Washington 98124-2207, for a copy of this service information. You may review copies at the Docket Management Facility, U.S. Department of Transportation, 400 Seventh Street, SW., Room PL-401, Nassif Building, Washington, DC; on the Internet at http://dms.dot.gov ; or at the National Archives and Records Administration (NARA). For information on the availability of this material at the 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 December 26, 2006. Ali Bahrami, Manager, Transport Airplane Directorate, Aircraft Certification Service. [FR Doc. E7-220 Filed 1-11-07; 8:45 am] BILLING CODE 4910-13-P

This AD results from a strut front spar chord assembly that was found fractured, forward of the inspection area required by AD 2004-25-05. We are issuing this AD to detect and correct cracks and fracture of the nacelle strut front spar chord assembly. Fracture of the front spar chord assembly could lead to 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 from the airplane.