AD 2010-20-12 Airworthiness Directives; The Boeing Company Model 747-400, 747-400D, and 747-400F Series Airplanes

Models named: 747-400, 747-400D, 747-400F series. Read the applicability below — it usually turns on serial or part numbers too.

This AD applies to The Boeing Company Model 747-400, 747-400D, and 747-400F series airplanes, certificated in any category; as identified in the service bulletins listed in paragraphs (c)(1) and (c)(2) of this AD. (1) Boeing Service Bulletin 747-28A2266, Revision 1, dated December 10, 2009. (2) Boeing Alert Service Bulletin 747-28A2267, dated December 18, 2008.

You are responsible for having the actions required by this AD performed within the compliance times specified, unless the actions have already been done. Installation of Hot Short Protector (HSP) (g) Within 60 months after the effective date of this AD: Do the applicable installations of the HSP specified in paragraphs (g)(1) and (g)(2) of this AD. Note 1: Boeing Service Bulletin 747-28A2266, Revision 1, dated December 10, 2009; and Boeing Alert Service Bulletin 747-28A2267, dated December 18, 2008; refer to Cinch Service Bulletin CN1036-28-01, Revision C, dated January 18, 2007, as an additional source of guidance for installing the HSP in the fuel tanks which must be done before or concurrently with the actions specified in Boeing Service Bulletin 747-28A2266, Revision 1, dated December 10, 2009; and Boeing Alert Service Bulletin 747-28A2267, dated December 18, 2008. (1) For all airplanes: Install the HSP in the center wing tank, in accordance with the Accomplishment Instructions of Boeing Service Bulletin 747-28A2266, Revision 1, dated December 10, 2009. (2) For airplanes identified in Boeing Alert Service Bulletin 747-28A2267, dated December 18, 2008: Install the HSP in the horizontal stabilizer tank, in accordance with the Accomplishment Instructions of Boeing Alert Service Bulletin 747-28A2267, dated December 18, 2008. Credit for Installation Previously Accomplished in Accordance With Previous Issue of Service Bulletin (h) Actions accomplished before the effective date of this AD according to Boeing Alert Service Bulletin 747-28A2266, dated December 18, 2008, are considered acceptable for compliance with the corresponding action specified in this AD, provided that Cinch Service Bulletin CN1036-28-01, Revision C, dated January 18, 2007, is used as an additional source of guidance. Alternative Methods of Compliance (AMOCs) (i)(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. Send information to ATTN: Georgios Roussos, Aerospace Engineer, Systems and Equipment Branch, ANM-130S, FAA, Seattle Aircraft Certification Office, 1601 Lind Avenue, SW., Renton, Washington 98057-3356; telephone (425) 917-6482; fax (425) 917-6590. Or, e-mail information to 9-ANM-Seattle-ACO-AMOC-Requests@faa.gov. (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 principal maintenance inspector (PMI) or principal avionics inspector (PAI), as appropriate, or lacking a principal inspector, your local Flight Standards District Office. The AMOC approval letter must specifically reference this AD. Material Incorporated by Reference (j) You must use Boeing Service Bulletin 747-28A2266, Revision 1, dated December 10, 2009; or Boeing Alert Service Bulletin 747-28A2267, dated December 18, 2008; as applicable; to do the actions required by this AD, unless the AD specifies otherwise. (1) 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. (2) 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; e-mail me.boecom@boeing.com; Internet https://www.myboeingfleet.com. (3) You may review copies of the service information at the 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. (4) You may also review copies of the 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/code_of_federal_regulations/ibr_locations.html. Issued in Renton, Washington, on September 16, 2010. Robert D. Breneman, Acting Manager, Transport Airplane Directorate, Aircraft Certification Service. [FR Doc. 2010-24169 Filed 9-30-10; 8:45 am] BILLING CODE 4910-13-P

This AD results from fuel system reviews conducted by the manufacturer. The Federal Aviation Administration is issuing this AD to prevent an electrical hot short from a source outside the fuel quantity indicating system (FQIS) to the densitometer wiring from causing failure of the FQIS densitometer resistors, which could result in an ignition source inside the center or horizontal stabilizer fuel tanks. An ignition source, in combination with flammable fuel vapors, could result in a fuel tank explosion and consequent loss of the airplane.