AD 2005-13-27 Airworthiness Directives; Boeing Model 737-300, -400, and -500 Series Airplanes

Models named: 737-300, -400, -500 series. Read the applicability below — it usually turns on serial or part numbers too.

This AD applies to Boeing Model 737-300, -400, and -500 series airplanes, certificated in any category; as identified in Boeing Special Attention Service Bulletin 737-53-1234, Revision 1, dated March 31, 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. Service Bulletin References (f) The term “service bulletin,” as used in this AD, means Boeing Special Attention Service Bulletin 737-53-1234, Revision 1, dated March 31, 2005. Initial and Repetitive Inspections (g) At the later of the times specified in paragraphs (g)(1) and (g)(2) of this AD, perform detailed and eddy current inspections for cracking of the crown area of the fuselage skin in accordance with Part 1, including the “Note,” of the Work Instructions of the service bulletin, except as provided by paragraph (j) of this AD. (1) Before the accumulation of the applicable total flight cycles specified in the “Threshold” column of Table 1 of Figure 1 of the service bulletin. (2) Within 4,500 flight cycles after the effective date of this AD. (h) Repeat either the detailed or eddy current inspections specified in paragraph (g) of this AD at the applicable intervals specified in paragraph (h)(1) or (h)(2) of this AD until paragraph (i)(1) or (i)(2) of this AD has been done, as applicable. (1) Repeat the detailed inspections thereafter at intervals not to exceed 1,200 flight cycles. (2) Repeat the eddy current inspections thereafter at intervals not to exceed 3,000 flight cycles. Permanent or Time-Limited Repair (i) If any cracking is found during any inspection required by paragraph (g) or (h) of this AD, do the actions specified in paragraph (i)(1) or (i)(2) of this AD in accordance with the service bulletin, except as provided by paragraphs (j) and (k) of this AD. (1) Before further flight, do a permanent repair (including related investigative actions and applicable corrective actions) in accordance with Part 2 of the Work Instructions of the service bulletin. Doing a permanent repair ends the repetitive inspections required by paragraph (h) of this AD for the repaired area only. (2) Do the actions specified in paragraphs (i)(2)(i) and (i)(2)(ii) of this AD at the time specified in the applicable paragraph. Doing a time-limited repair ends the repetitive inspections required by paragraph (h) of this AD for the repaired area only. (i) Before further flight, do a time-limited repair (including related investigative actions and applicable corrective actions) in accordance with Part 3 of the Work Instructions of the service bulletin. (ii) At the times specified in Figure 8 of the service bulletin, do the related investigative and corrective actions in accordance with Part 3 of the Work Instructions of the service bulletin. Contact the FAA (j) Where the service bulletin specifies to contact Boeing for appropriate action: Before further flight, repair according to a method approved by the Manager, Seattle Aircraft Certification Office (ACO), FAA; or according to data meeting the certification basis of the airplane approved by an Authorized Representative for the Boeing 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 approval must specifically reference this AD. No Reporting (k) Although the service bulletin specifies reporting certain information to Boeing, this AD does not require that action. Actions Accomplished According to Previous Issue of Service Bulletin (l) Actions done before the effective date of this AD in accordance with Boeing Special Attention Service Bulletin 737-53-1234, dated June 13, 2002, are acceptable for compliance with the corresponding actions required by this AD. Alternative Methods of Compliance (AMOCs) (m) The Manager, Seattle ACO, FAA, has the authority to approve AMOCs for this AD, if requested using the procedures found in 14 CFR 39.19. Material Incorporated by Reference (n) You must use Boeing Special Attention Service Bulletin 737-53-1234, Revision 1, dated March 31, 2005, 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. To get copies of the service information, contact Boeing Commercial Airplanes, P.O. Box 3707, Seattle, Washington 98124-2207. To view the AD docket, go to the Docket Management Facility, U.S. Department of Transportation, 400 Seventh Street SW., room PL-401, Nassif Building, Washington, DC. To review copies of the service information, go to 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 June 15, 2005. Kevin M. Mullin, Acting Manager, Transport Airplane Directorate, Aircraft Certification Service. [FR Doc. 05-12514 Filed 6-24-05; 8:45 am] BILLING CODE 4910-13-P

This AD was prompted by a Model 737 fuselage structure test and fatigue analysis that indicate fuselage skin cracking could occur between 21,000 and 42,000 total flight cycles. We are issuing this AD to detect and correct fatigue cracking of the fuselage skin, which could cause the fuselage skin to fracture and fail, and could result in rapid decompression of the airplane.