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2012-23-08: Nacelles/pylons

FAA order 2012-23-08 is an airworthiness directive in force since December 31, 2012. The FAA's subject line: Nacelles/pylons. It names Boeing 737: about 2,896 aircraft on the U.S. register today, though an order usually covers particular versions or serial numbers rather than every one. System: engine.

What it applies to as the FAA lists it

Kind of product
Aircraft
Makes
The Boeing Company
Models
737-600 Series, 737-700 Series, 737-700C Series, 737-800 Series, 737-900 Series, 737-900ER Series
On this site
Boeing 737 2,896 registered

Dates and paperwork

In force since
December 31, 2012
Published
November 26, 2012 (signed November 9, 2012)
Docket
FAA-2012-0591
Replaces
2008-08-24
Status
Current
The FAA's document
Read the order on the FAA's site

The FAA's summary their words, unchanged

We are superseding an existing airworthiness directive (AD) for certain The Boeing Company Model 737-600, -700, -700C, -800, and - 900 series airplanes. That AD currently requires replacing the drain tube assemblies and support clamps on the aft fairing of the engine struts. This new AD requires replacing the drain tube assembly of the left and right engine strut aft fairings with a new one, which includes an integral support clamp made of nickel alloy 625. This AD also adds airplanes to the applicability. This AD was prompted by a report of a broken drain tube assembly on the left engine strut at the clamp support location under the aft fairing compartment, inside the heat shield cavity of the aft fairing. There have also been reports of tube wear at this clamp location on additional airplanes. We are issuing this AD to prevent failure of the drain tube assemblies and clamps on the aft fairings of the engine struts. Such failure could allow leaked flammable fluids in the drain systems to discharge onto the heat shields of the aft fairings of the engine struts, which could result in an undetected and uncontrollable fire.

The order itself the regulatory text, as published

Show the full text (5,578 characters)
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\nSec. 39.13 (Amended) \n\n0 2. The FAA amends Sec. 39.13 by removing airworthiness directive (AD) 2008-08-24, Amendment 39-15478 (73 FR 21242, April 21, 2008), and adding the following new AD: \n\n2012-23-08 The Boeing Company: Amendment 39-17264; Docket No. FAA- 2012-0591; Directorate Identifier 2012-NM-015-AD. \n\n(a) Effective Date \n\n\n\tThis airworthiness directive (AD) is effective December 31, 2012. \n\n(b) Affected ADs \n\n\n\tThis AD supersedes AD 2008-08-24, Amendment 39-15478 (73 FR 21242, April 21, 2008). \n\n(c) Applicability \n\n\n\t(1) This AD applies to The Boeing Company Model 737-600, -700, - 700C, -800, -900, and -900ER series airplanes, certificated in any category, as identified in Boeing Special Attention Service Bulletin 737-54-1043, Revision 2, dated November 4, 2011. \n\t(2) Supplemental Type Certificate (STC) ST00830SE (http://rgl.faa.gov/Regulatory_and_Guidance_Library/rgstc.nsf/0/408E012E008616A7862578880060456C?OpenDocument&Highlight=st00830se) does not affect the ability to accomplish the actions required by this AD. Therefore, for airplanes on which STC ST00830SE 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. For all other AMOC requests, the operator must request approval for an AMOC in accordance with the procedures specified in paragraph (h) of this AD. \n\n(d) Subject \n\n\n\tJoint Aircraft System Component (JASC)/Air Transport Association (ATA) of America Code 54, Nacelles/pylons. \n\n(e) Unsafe Condition \n\n\n\tThis AD was prompted by a report of a broken drain tube assembly on the aft fairing of the left engine strut at the clamp support location under the aft fairing compartment, inside the heat shield cavity of the aft fairing. There have also been reports of tube wear at the clamp location on additional airplanes. We are issuing this AD to prevent failure of the drain tube assemblies and clamps on the aft fairings of the engine struts. Such failure could allow leaked flammable fluids in the drain systems to discharge onto the heat shields of the aft fairings of the engine struts, which could result in an undetected and uncontrollable fire. \n\n(f) Compliance \n\n\n\tComply with this AD within the compliance times specified, unless already done. \n\n(g) Replacement \n\n\n\tWithin 60 months after the effective date of this AD, replace the drain tube assemblies and support clamps on the aft fairing of the struts of engines 1 and 2 with new drain tube assemblies and clamps, in accordance with the Accomplishment Instructions of Boeing Special Attention Service Bulletin 737-54-1043, Revision 2, dated November 4, 2011. \n\n((Page 70360)) \n\n(h) 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: [email protected]. \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) AMOCs approved previously in accordance with AD 2008-08-24, Amendment 39-15478 (73 FR 21242, April 21, 2008), are not approved as AMOCs with thisAD. \n\n(i) Related Information \n\n\n\tFor more information about this AD, contact Ansel James, Aerospace Engineer, Propulsion Branch, ANM-140S, FAA, Seattle Aircraft Certification Office, 1601 Lind Avenue SW., Renton, WA 98057-3356; phone: 425-917-6497; fax: 425-917-6590; email: [email protected]. \n\n(j) 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 the AD specifies otherwise. \n\t(i) Boeing Special Attention Service Bulletin 737-54-1043, Revision 2, dated November 4, 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, WA 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 \n\tDirectorate, 1601 Lind Avenue SW., Renton, WA. 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 at NARA, call 202-741-6030, or go to: http://www.archives.gov/federal-register/cfr/ibr-locations.html.

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Source: FAA Dynamic Regulatory System, airworthiness directives. The FAA's document is the authority; the register counts are this site's, from the FAA register of November 6, 2026. Connections as data: /graph/directive/2012-23-08.json · aircraft systems.