AD 2008-09-13 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 all Boeing Model 737-300, -400, and -500 series airplanes, 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. Service Information (f) The term “the SSID,” as used in this AD, means Boeing Document D6-82669, “Supplemental Structural Inspection Document Models 737-300/400/500 Airplanes,” Original Release, dated May 2007. Revision of the FAA-Approved Maintenance Inspection Program (g) Before the accumulation of 66,000 total flight cycles, or within 12 months after the effective date of this AD, whichever occurs later, incorporate a revision into the FAA-approved maintenance inspection program that provides no less than the required damage tolerance rating (DTR) for each structural significant item (SSI) listed in the SSID. (The required DTR value for each SSI is listed in the SSID.) The revision to the maintenance inspection program must include and must be implemented in accordance with the procedures in Section 5.0, “Damage Tolerance Rating (DTR) System Application,” and Section 6.0, “SSI Discrepancy Reporting” of the SSID. Under the provisions of the Paperwork Reduction Act of 1980 (44 U.S.C. 3501 et seq. ), the Office of Management and Budget (OMB) has approved the information collection requirements contained in this AD and has assigned OMB Control Number 2120-0056. Initial and Repetitive Inspections (h) Except as provided by paragraph (i) of this AD: Before the accumulation of 66,000 total flight cycles, or within 4,000 flight cycles measured from 12 months after the effective date of this AD, whichever occurs later, do the applicable initial inspections to detect cracks of all SSIs, in accordance with the SSID. Repeat the applicable inspections thereafter at the intervals specified in Section 3.0, “Implementation” of the SSID. (i) For any SSI that has been repaired or altered before the effective date of this AD such that the repair or design change affects your ability to accomplish the actions required by paragraph (h) of this AD: You must request FAA approval of an alternative method of compliance (AMOC) in accordance with section 39.17 of the Federal Aviation Regulations (14 CFR 39.17), at the initial compliance time specified in paragraph (h) of the AD; or do the actions specified in paragraphs (i)(1) and (i)(2) of this AD, at the times specified in those paragraphs, as an approved means of compliance with the requirements of paragraph (h) of this AD. (1) At the initial compliance time specified in paragraph (h) of the AD, identify each repair or design change to that SSI. (2) Within 12 months after the identification of a repair or design change required by paragraph (i)(1) of this AD, assess the damage tolerance characteristics of each SSI affected by each repair or design change to determine the effectiveness of the applicable SSID inspection for that SSI and if not effective, incorporate a revision into the FAA-approved maintenance inspection program to include a damage-tolerance based alternative inspection program for each affected SSI. Thereafter, inspect the affected structure in accordance with the alternative inspection program. The inspection method and compliance times (i.e., threshold and repeat intervals) of the alternative inspection program must be approved in accordance with the procedures specified in paragraph (l) of this AD. Repair (j) If any cracked structure is found during any inspection required by paragraph (h) or (i) of this AD, before further flight, repair the cracked structure using a method approved in accordance with the procedures specified in paragraph (l) of this AD. Inspection Program for Transferred Airplanes (k) Before any airplane that is subject to this AD and that has exceeded the applicable compliance times specified in paragraph (h) of this AD can be added to an air carrier's operations specifications, a program for the accomplishment of the inspections required by this AD must be established in accordance with paragraph (k)(1) or (k)(2) of this AD, as applicable. (1) For airplanes that have been inspected in accordance with this AD: The inspection of each SSI must be done by the new operator in accordance with the previous operator's schedule and inspection method, or the new operator's schedule and inspection method, at whichever time would result in the earlier accomplishment for that SSI inspection. The compliance time for accomplishment of this inspection must be measured from the last inspection accomplished by the previous operator. After each inspection has been done once, each subsequent inspection must be performed in accordance with the new operator's schedule and inspection method. (2) For airplanes that have not been inspected in accordance with this AD: The inspection of each SSI required by this AD must be done either before adding the airplane to the air carrier's operations specification, or in accordance with a schedule and an inspection method approved by the Manager, Seattle Aircraft Certification Office (ACO), FAA. After each inspection has been done once, each subsequent inspection must be done in accordance with the new operator's schedule. Alternative Methods of Compliance (AMOCs) (l)(1) The Manager, Seattle ACO, has the authority to approve AMOCs for this AD, if requested in accordance with the procedures found in 14 CFR 39.19. (2) To request a different method of compliance or a different compliance time for this AD, follow the procedures in 14 CFR 39.19. Before using any approved AMOC on any airplane to which the AMOC applies, notify your appropriate principal inspector (PI) in the FAA Flight Standards District Office (FSDO), or lacking a PI, your local FSDO. (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 approval must specifically refer to this AD. Material Incorporated by Reference (m) You must use Boeing Document D6-82669, “Supplemental Structural Inspection Document Models 737-300/400/500 Airplanes,” Original Release, dated May 2007, to do the actions required by this AD, unless the AD specifies otherwise. (1) The document contains the following errors: (i) Pages 8.0.3 and 8.0.4 of Section 8.0, as specified in the List of Effective Pages, do not exist. (ii) There are two sets of pages (four pages total) with the same page numbers in Section 11.3 (i.e., pages E.30.1 and E.30.2). The first set of page numbers (i.e., DTR Check Form for Item E-30 and the following blank page) is correct. The second set of page numbers (i.e., DTR Check Form for Item E-31 and the following blank page) is incorrect. Those pages should be identified as page numbers 31.1 and 31.2, as specified in the List of Effective Pages. (iii) None of the pages are dated. The issue date for those pages is May 2007, as specified in the Revision Highlights section. (2) The Director of the Federal Register approved the incorporation by reference of this service information under 5 U.S.C. 552(a) and 1 CFR part 51. (3) For service information identified in this AD, contact Boeing Commercial Airplanes, P.O. Box 3707, Seattle, Washington 98124-2207. (4) You may review copies of the service information incorporated by reference at the FAA, Transport Airplane Directorate, 1601 Lind Avenue, SW., Renton, Washington; 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 April 8, 2008. Ali Bahrami, Manager, Transport Airplane Directorate, Aircraft Certification Service. [FR Doc. E8-9316 Filed 5-1-08; 8:45 am] BILLING CODE 4910-13-P

This AD results from a report of incidents involving fatigue cracking in transport category airplanes that are approaching or have exceeded their design service objective. We are issuing this AD to maintain the continued structural integrity of the entire fleet of Model 737-300, -400, and -500 series airplanes.