AD 2013-15-14

We are superseding airworthiness directive (AD) 2008-06-29, which applied to all The Boeing Company Model 737-300, -400, and -500 series airplanes. AD 2008-06-29 required repetitive inspections of the downstop assemblies on the main tracks of the No. 2, 3, 4, and No. 5 slats and the inboard track of the No. 1 and 6 slats to verify if any parts are missing, damaged, or in the wrong order; other specified actions; and related investigative and corrective actions if necessary. This new AD retains these requirements and adds an inspection of the slat can interior for foreign object debris (FOD), and removal of any FOD found; modification of the slat track hardware; an inspection for FOD and for damage to the interior surface of the slat cans; and related investigative and corrective actions, if necessary. This AD was prompted by development of a modification by the manufacturer, which, when installed, would terminate the repetitive inspections. We are issuing this AD to prevent loose or missing parts in the main slat track downstop assemblies, which could puncture the slat track housing and result in a fuel leak and consequent fire.

Final rule.

Adoption of the Amendment \n\n\n\tAccordingly, under the authority delegated to me by the Administrator, the FAA amends 14 CFR part 39 as follows: \n\nPART 39--AIRWORTHINESS DIRECTIVES \n\n0 1. The authority citation for part 39 continues to read as follows: \n\n\n\tAuthority: 49 U.S.C. 106(g), 40113, 44701. \n\n\n\nSec. 39.13 (Amended) \n\n0 2. The FAA amends Sec. 39.13 by removing airworthiness directive (AD) 2008-06-29, Amendment 39-15441 (73 FR 15397, March 24, 2008), and adding the following new AD: \n\n2013-15-14 The Boeing Company: Amendment 39-17530; Docket No. FAA- 2013-0207; Directorate Identifier 2011-NM-071-AD. \n\n(a) Effective Date \n\n\n\tThis AD is effective September 20, 2013. \n\n(b) Affected ADs \n\n\n\tThis AD supersedes AD 2008-06-29, Amendment 39-15441 (73 FR 15397, March 24, 2008). \n\n(c) Applicability \n\n\n\t(1) This AD applies to all The Boeing Company Model 737-300, - 400, and -500 series airplanes, certificated in any category. \n\t(2) Installation of Supplemental Type Certificate (STC) ST01219SE (http://rgl.faa.gov/Regulatory_and_Guidance_Library/rgstc.nsf/0/2C6E3DBDDD36F91C862576A4005D64E2?OpenDocument&Highlight=st01219se) does not affect the ability to accomplish the actions required by this AD. Therefore, for airplanes on which STC ST01219SE is installed, a ''change in product'' alternative method of compliance (AMOC) approval request is not necessary to comply with the requirements of 14 CFR 39.17. \n\n(d) Subject \n\n\n\tJoint Aircraft System Component (JASC)/Air Transport Association (ATA) of America Code 57: Wings. \n\n(e) Unsafe Condition \n\n\n\tThis AD was prompted by reports of fuel leaking from a puncture in the slat track housing (referred to as ''slat can''). We are issuing this AD to prevent loose or missing parts in the main slat track downstop assemblies, which could puncture the slat track housing and result in a fuel leak and consequent fire. \n\n(f) Compliance \n\n\n\tComply with this AD within the compliance times specified, unless already done. \n\n(g) Retained Inspection of Downstop Assemblies and Corrective Action \n\n\n\tThis paragraph restates the requirements of paragraph (f) of AD 2008-06-29, Amendment 39-15441 (73 FR 15397, March 24, 2008), with revised service information. At the applicable times specified in Table 1 of paragraph 1.E. of Boeing Alert Service Bulletin 737- 57A1301, dated February 5, 2008; or Boeing Service Bulletin 737- 57A1301, Revision 3, dated August 11, 2011; except as provided by paragraph (g)(1) of this AD: Do a detailed inspection or borescope inspection of the downstop assemblies on the main tracks of the No. 2, 3, 4, and 5 slats and the inboard track of the No. 1 and 6 slats to verify if any parts are missing, damaged, or installed in the wrong order; and do all the other specified, related investigative, and corrective actions as applicable; by accomplishing all of the applicable actions specified in the Accomplishment Instructions of Boeing Alert Service Bulletin 737-57A1301, dated February 5, 2008; or Boeing Service Bulletin 737-57A1301, Revision 3, dated August 11, 2011; except as provided by paragraphs (g)(2) and (g)(3) of this AD. Repeat the inspection thereafter at the applicable times specified in Table 1 of paragraph 1.E. of Boeing Alert Service Bulletin 737- 57A1301, dated February 5, 2008; or Boeing Service Bulletin 737- 57A1301, Revision 3, dated August 11, 2011. Do all applicable related investigative and corrective actions before further flight. As of the effective date of this AD, only Boeing Service Bulletin 737-57A1301, Revision 3, dated August 11, 2011, may be used to accomplish the actions required by this paragraph. \n\t(1) Where Boeing Alert Service Bulletin 737-57A1301, dated February 5, 2008, or Boeing Service Bulletin 737-57A1301, Revision 3, dated August 11, 2011, specifies counting the compliance time from ''the date on the service bulletin,'' this AD requires counting the compliance time from April 8, 2008 (the effective date of AD 2008-06-29, Amendment 39-15441 (73 FR 15397, March 24, 2008)). \n\t(2) For airplanes on which any downstop assembly part is missing or damaged, a borescope inspection of the inside of the slat track housing for loose parts and damage to the wall of the slat track housing may be accomplished in lieu of the detailed inspection of the inside of the slat track housing that is specified in Boeing Alert Service Bulletin 737-57A1301, dated February 5, 2008; or Boeing Service Bulletin 737-57A1301, Revision 3, dated August 11, 2011. As of the effective date of this AD, only Boeing Service Bulletin 737-57A1301, Revision 3, dated August 11, 2011, may be used to do the actions specified in this paragraph. \n\t(3) If any damaged slat track housing is found during any inspection required by paragraph (g) of this AD: Before further flight, repair in accordance with the Accomplishment Instructions of Boeing Service Bulletin 737-57A1301, Revision 3, dated August 11, 2011; replace the slat can with a new slat can having the same part number, in accordance with the Accomplishment Instructions of Boeing Service Bulletin 737-57A1301, Revision 3, dated August 11, 2011; or repair the slat can using a method approved in accordance with the procedures specified in paragraph (k) of this AD. \n\n(h) New Detailed Inspection for Foreign Object Debris (FOD) \n\n\n\tWithin 24 months after the effective date of this AD, do a one- time detailed inspection of the slat can interior to detect FOD, in accordance with Part III of the Accomplishment Instructions of Boeing Service Bulletin 737-57A1301, Revision 3, dated August 11, 2011. If any FOD is found, before further flight, remove it, in accordance with the Accomplishment Instructions of Boeing Service Bulletin 737-57A1301, Revision 3, dated August 11, 2011. \n\n(i) New Modification and Inspection \n\n\n\tWithin 72 months or 15,000 flight cycles, whichever occurs first, after the effective date of this AD: Modify the slat track hardware by installing new downstop assembly hardware, and do a detailed inspection for FOD and a one-time inspection for damage to the interior surface of the slat can for the inboard and outboard tracks of slats 2 through 5, and the inboard slats of tracks 1 and 6; and do all applicable related investigative and corrective actions; in accordance with the Accomplishment Instructions of Boeing Service Bulletin 737-57A1301, Revision 3, dated August 11, 2011. Do all applicable related investigative and corrective actions before further flight. Accomplishment of the actions required by this paragraph terminates the inspections required by paragraphs (g) and (h) of this AD. \n\n(j) Credit for Previous Actions \n\n\n\tThis paragraph provides credit for the actions required by paragraphs (g), (h), and (i) of this AD, if those actions were performed before the effective date of this AD using Boeing Alert Service Bulletin 737-57A1301, Revision 1, dated September 24, 2009; or Boeing Alert Service Bulletin 737-57A1301, Revision 2, dated January 17, 2011; which are not incorporated by reference in this AD. \n\n(k) Alternative Methods of Compliance (AMOCs) \n\n\n\t(1) The Manager, Seattle Aircraft Certification Office (ACO), FAA, has the authority to approve AMOCs for this AD, if requested using the procedures found in 14 CFR 39.19. In accordance with 14 CFR 39.19, send your request to your principal inspector or local Flight Standards District Office, as appropriate. If sending information directly to the manager of the ACO, send it to the attention of the person identified in the Related Information section of this AD. Information may be emailed to: 9-ANM-Seattle-ACO-AMOC-Requests@faa.gov. \n\t(2) Before using any approved AMOC, notify your appropriate principal inspector, or lacking a principal inspector, the manager of the local flight standards district office/certificate holding district office. \n\t(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 the Boeing Commercial Airplanes Organization Designation Authorization (ODA) that has \n\n((Page 49913)) \n\nbeen 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. \n\t(4) AMOCs approved previously in accordance with AD 2008-06-29, Amendment 39-15441 (73 FR 15397, March 24, 2008), are approved as AMOCs for the corresponding provisions of this AD. \n\n(l) Related Information \n\n\n\tFor more information about this AD, contact Nancy Marsh, Aerospace Engineer, Airframe Branch, ANM-120S, FAA, Seattle Aircraft Certification Office (ACO), 1601 Lind Avenue SW., Renton, WA 98057- 3356; phone: (425) 917-6440; fax: (425) 917-6590; email: nancy.marsh@faa.gov. \n\n(m) Material Incorporated by Reference \n\n\n\t(1) The Director of the Federal Register approved the incorporation by reference (IBR) of the service information listed in this paragraph under 5 U.S.C. 552(a) and 1 CFR part 51. \n\t(2) You must use this service information as applicable to do the actions required by this AD, unless this AD specifies otherwise. \n\t(i) Boeing Service Bulletin 737-57A1301, Revision 3, dated August 11, 2011. \n\t(ii) Reserved. \n\t(3) For service information identified in this AD, contact Boeing Commercial Airplanes, Attention: Data & Services Management, P.O. Box 3707, MC 2H-65, Seattle, Washington 98124-2207; telephone 206-544-5000, extension 1; fax 206-766-5680; Internet https://www.myboeingfleet.com. \n\t(4) You may view this service information at FAA, Transport Airplane Directorate, 1601 Lind Avenue SW., Renton, Washington. For information on the availability of this material at the FAA, call 425-227-1221. \n\t(5) You may view this service information that is incorporated by reference at the National Archives and Records Administration (NARA). For information on the availability of this material atNARA, call 202-741-6030, or go to: http://www.archives.gov/federal-register/cfr/ibr-locations.html.

Discussion \n\n\n\tWe issued a notice of proposed rulemaking (NPRM) to amend 14 CFR part 39 to supersede AD 2008-06-29, Amendment 39-15441 (73 FR 15397, March 24, 2008) (''AD 2008-06-29''). AD 2008-06-29 applied to the specified products. The NPRM published in the Federal Register on March 11, 2013 (78 FR 15332). The NPRM proposed to continue to require repetitive inspections of the downstop assemblies on the main tracks of the No. 2, 3, 4, and No. 5 slats and the inboard track of the No. 1 and 6 slats to verify if any parts are missing, damaged, or in the wrong order; other specified actions; and related investigative and corrective actions if necessary. The NPRM also proposed to add an inspection of the slat can interior for foreign object debris (FOD), and removal of any FOD found; modification of the slat track hardware; an inspection for FOD and for damage to the interior surface of the slat cans; and related investigative and corrective actions, if necessary. \n\nComments \n\n\n\tWe gave the public the opportunity to participate in developing this AD. The following presents the comments received on the proposal (78 FR 15332, March 11, 2013) and the FAA's response to each comment. \n\nConcurrence With NPRM (78 FR 15332, March 11, 2013) \n\n\n\tBoeing stated that it concurs with the content of the proposed rule (78 FR 15332, March 11, 2013). \n\nStatement Regarding Installation of Winglets \n\n\n\tAviation Partners Boeing (APB) stated that the installation of winglets per STC ST01219SE (http://rgl.faa.gov/Regulatory_and_Guidance_Library/rgstc.nsf/0/2C6E3DBDDD36F91C862576A4005D64E2?OpenDocument&Highlight=st01219se) does not affect the actions specified in the NPRM (78 FR 15332, March 11, 2013). \n\tWe concur. We have added new paragraph (c)(2) to this AD, which states that STC ST01219SE (http://rgl.faa.gov/Regulatory_and_Guidance_Library/rgstc.nsf/0/2C6E3DBDDD36F91C862576A4005D64E2?OpenDocument&Highlight=st01219se) does not affect the ability to accomplish the actions required by this AD. Therefore, for airplanes on which STC ST01219SE is installed, a ''change in product'' alternative method of compliance (AMOC) approval request is not necessary to comply with the requirements of Section 39.17 of the Federal Aviation Regulations (14 CFR 39.17). For all other AMOC requests, the operator must request approval of an AMOC in accordance with the procedures specified in paragraph (k) of this AD. \n\nConclusion \n\n\n\tWe reviewed the relevant data, considered the comments received, and determined that air safety and the public interest require adopting this AD with the change described previously--and minor editorial changes. We have determined that these minor changes: \n\tAre consistent with the intent that was proposed in the NPRM (78 FR 15332, March 11, 2013) for correcting the unsafe condition; and \n\tDo not add any additional burden upon the public than was already proposed in the NPRM (78 FR 15332, March 11, 2013).We also determined that these changes will not increase the economic burden on any operator or increase the scope of this AD. \n\nCosts of Compliance \n\n\n\tWe estimate that this AD affects 568 airplanes of U.S. registry. \n\tWe estimate the following costs to comply with this AD: \n\n\n\tEstimated costs ---------------------------------------------------------------------------------------------------------------- \n\tCost per Cost on U.S. \n\tAction Labor cost Parts cost product operators ---------------------------------------------------------------------------------------------------------------- Inspection of slat track housing 4 work-hours x $85 per $0 $340 $193,120 \n\t(retained actions from AD 2008-06-29 hour = $340 per \n\t(73 FR 15397, March 24, 2008)). inspection cycle. One-time detailed inspection of slat 5 work-hours x $85 per 0 425 241,400 \n\tcan (new action). hour = $85. Installation of modification (new 12 work-hours x $85 per 3,124 4,144 2,353,792 \n\taction). hour = $1,020. ---------------------------------------------------------------------------------------------------------------- \n\n\n\tWe have received no definitive data that would enable us to provide a cost estimate for the on-condition actions specified in this AD. \n\nAuthority for This Rulemaking \n\n\n\tTitle 49 of the United States Code specifies the FAA's authority to issue rules on aviation safety. Subtitle I, Section 106, describes the authority of the FAA Administrator. Subtitle VII, Aviation Programs, describes in more detail the scope of the Agency's authority. \n\tWe are issuing this rulemaking under the authority described in Subtitle VII, Part A, Subpart III, Section 44701, ''General requirements.'' Under that section, Congress charges the FAA with promoting safe flight of civil aircraft in air commerce by prescribing regulations for practices, methods, and procedures the Administrator finds necessary for safety in air commerce. This regulation is within the scope of that authority because it addresses an unsafe condition that is likely to exist or develop on products identified in this rulemaking action. \n\nRegulatory Findings \n\n\n\tWe have determined that this AD will not have federalism implications under Executive Order 13132. This AD will not have a substantial direct effect on the States, on the relationship between the national government and the States, or on the distribution of power and responsibilities among the various levels of government. \n\tFor the reasons discussed above, I certify that this AD: \n\t(1) Is not a ''significant regulatory action'' under Executive Order 12866, \n\t(2) Is not a ''significant rule'' under DOT Regulatory Policies and Procedures (44 FR 11034, February 26, 1979), \n\t(3) Will not affect intrastate aviation in Alaska, and \n\t(4) Will not have a significant economic impact, positive or negative, on a substantial number of small entities under the criteria of the Regulatory Flexibility Act. \n\n((Page 49912)) \n\nList of Subjects in 14 CFR Part 39 \n\n\n\tAir transportation, Aircraft, Aviation safety, Incorporation by reference, Safety.