AD 2005-05-07 Airworthiness Directives; Boeing Model 747-100, -100B, -100B SUD, -200B, -200C, -200F, and -300 Series Airplanes; and Model 747SP and 747SR Series Airplanes; Equipped With Pratt and Whitney Model JT9D-3 or -7 (Except -70) Series Engines

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

This AD applies to Boeing Model 747-100, -100B, -100B SUD, -200B, -200C, -200F, and -300 series airplanes; and Model 747SP and 747SR series airplanes; equipped with Pratt and Whitney Model JT9D-3, or -7 (except for -70) series engines; as identified in Boeing Alert Service Bulletin 747-54A2220, dated July 31, 2003; 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. Repetitive Inspections and Repair (f) Within 9 months after the effective date of this AD, do a detailed inspection to detect cracking of the aft and forward surfaces of the bulkhead web at nacelle station 180, in accordance with the Accomplishment Instructions of Boeing Alert Service Bulletin 747-54A2220, dated July 31, 2003. (1) If no cracking is detected, repeat the detailed inspection at the applicable intervals specified in the “Repeat Inspection Interval” column of Tables 1 and 2 in Figure 1 of the service bulletin. (2) If any cracking is detected, before further flight, repair the cracking in accordance with the service bulletin, except as provided by paragraph (f)(3) of this AD. Thereafter, repeat the detailed inspection at the applicable intervals specified in the “Repeat Inspection Interval” column of Tables 1 and 2 in Figure 1 of the service bulletin. (3) If any cracking exceeds the repair limits specified in the applicable structural repair manual (referenced in the service bulletin), before further flight, repair the cracking in accordance with a method approved by the Manager, Seattle Aircraft Certification Office (ACO), FAA; or in accordance with data meeting the certification basis of the airplane approved by an Authorized Representative (AR) for the Boeing Delegation Option Authorization (DOA) 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. Alternative Methods of Compliance (AMOCs) (g)(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 an AR for the Boeing DOA 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 (h) You must use Boeing Alert Service Bulletin 747-54A2220, dated July 31, 2003, 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, P.O. Box 3707, Seattle, Washington 98124-2207. For information on the availability of this material at the National Archives and Records Administration (NARA), call (202) 741-6030, or go to http://www.archives.gov/federal_register/code_of_federal_regulations/ibr_locations.html. You may view the AD docket at the Docket Management Facility, U.S. Department of Transportation, 400 Seventh Street SW, room PL-401, Nassif Building, Washington, DC. Issued in Renton, Washington, on February 28, 2005. Ali Bahrami, Manager, Transport Airplane Directorate, Aircraft Certification Service. [FR Doc. 05-4411 Filed 3-10-05; 8:45 am] BILLING CODE 4910-13-P

This AD was prompted by reports of cracking of the web bulkhead at nacelle station 180. We are issuing this AD to detect and correct fatigue cracking of the web bulkhead, and consequent loss of the load path of the bulkhead at nacelle station 180, which when combined with the loss of the midspar load path, could result in the in-flight separation of the engine and strut. Such separation may result in secondary damage to the airplane and consequent reduced controllability of the airplane.