AD 2006-05-09 Airworthiness Directives; Boeing Model 747-200C, -200F, -400, -400D, and -400F Series Airplanes

Models named: 747-200C, -200F, -400, -400D, -400F series. Read the applicability below — it usually turns on serial or part numbers too.

This AD applies to Boeing Model 747-200C, -200F, -400, -400D, and -400F series airplanes, certificated in any category; as identified in Boeing Alert Service Bulletin 747-53A2499, dated August 11, 2005.

You are responsible for having the actions required by this AD performed within the compliance times specified, unless the actions have already been done. Initial Inspections and Related Investigative and Corrective Actions (f) At the applicable time specified in Table 1 of this AD: Do an external surface high frequency eddy current (HFEC), external low frequency eddy current (LFEC), and internal LFEC inspection, as applicable, for cracks in the overlapping (upper) skin, upper fastener row of the lap joints of the fuselage skin in sections 41, 42, and 46, and any applicable related investigative and corrective actions by doing all of the actions in accordance with the Accomplishment Instructions of Boeing Alert Service Bulletin 747-53A2499, dated August 11, 2005, except as provided by paragraph (h) of this AD. Do any applicable related investigative and corrective actions before further flight. Table 1.—Initial Compliance Time For airplanes on which Structural Significant Items (SSIs) F-25G, F-25H, and F-25I— Inspect— (1) Have not been inspected in accordance with paragraph (d) of AD 2004-07-22, amendment 39-13566 (69 FR 24063, May 3, 2004), using the HFEC method Before the accumulation of 22,000 total flight cycles, or within 1,000 flight cycles after the effective date of this AD, whichever occurs later. (2) Have been inspected in accordance with paragraph (d) of AD 2004-07-22, using the HFEC method Within 3,000 flight cycles after the most recent supplemental structural inspection document (SSID) inspection of each applicable structural significant item (as given in Boeing Document D6-35022, “SSID for Model 747 Airplanes,” Revision G, dated December 2000), or within 1,000 flight cycles after the effective date of this AD, whichever occurs later. Repetitive Inspections (g) Repeat the applicable inspections required by paragraph (f) of this AD thereafter at intervals not to exceed those specified in paragraph 1.E., “Compliance” (including the note) of Boeing Alert Service Bulletin 747-53A2499, dated August 11, 2005. Exception to Service Bulletin Instructions (h) Where the service bulletin specifies to contact Boeing for appropriate action, before further flight, repair the crack using a method approved in accordance with the procedures specified in paragraph (i) of this AD. Alternative Methods of Compliance (AMOCs) (i)(1) The Manager, Seattle Aircraft Certification Office (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 (j) You must use Boeing Alert Service Bulletin 747-53A2499, dated August 11, 2005, to perform the actions that are required by this AD, unless the AD specifies otherwise. The Director of the Federal Register approved the incorporation by reference of this document in accordance with 5 U.S.C. 552(a) and 1 CFR part 51. 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 February 27, 2006. Ali Bahrami, Manager, Transport Airplane Directorate, Aircraft Certification Service. [FR Doc. 06-2142 Filed 3-8-06; 8:45 am] BILLING CODE 4910-13-P

This AD results from fatigue tests and an analysis that identified areas of the fuselage lap joints where fatigue cracks can occur. We are issuing this AD to detect and correct fatigue cracks in the overlapping (upper) skin, upper fastener row of the lap joints of the fuselage skin in sections 41, 42, and 46, which could adversely affect the structural integrity of the airplane.