AD 2008-14-14 Airworthiness Directives; Boeing Model 747-400 and 747-400D Series Airplanes

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

This AD applies to Boeing Model 747-400 and 747-400D series airplanes, certificated in any category; as identified in Boeing Special Attention Service Bulletin 747-24-2257, Revision 1, dated August 2, 2007.

You are responsible for having the actions required by this AD performed within the compliance times specified, unless the actions have already been done. Inspection and Related Investigative and Corrective Actions (f) Within 24 months after the effective date of this AD, do a general visual inspection of the power feeder wire bundle of the APU where it crosses the hydraulic system 4 return tube to determine if parts are installed to provide separation between the wire bundle and hydraulic tube, and do all the related investigative and corrective actions as applicable, by accomplishing all of the actions specified in the Accomplishment Instructions of Boeing Special Attention Service Bulletin 747-24-2257, Revision 1, dated August 2, 2007. The related investigative and corrective actions must be accomplished before further flight after the inspection. Credit for Actions Done According to Previous Issue of Service Bulletin (g) Actions done before the effective date of this AD in accordance with Boeing Special Attention Service Bulletin 747-24-2257, dated May 18, 2006, are acceptable for compliance with the corresponding requirements of paragraph (f) of this AD. Alternative Methods of Compliance (AMOCs) (h)(1) The Manager, Seattle Aircraft Certification Office, FAA, 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. Material Incorporated by Reference (i) You must use Boeing Special Attention Service Bulletin 747-24-2257, Revision 1, dated August 2, 2007, 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, P.O. Box 3707, Seattle, Washington 98124-2207. (3) 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 June 27, 2008. Ali Bahrami, Manager, Transport Airplane Directorate, Aircraft Certification Service. [FR Doc. E8-15710 Filed 7-16-08; 8:45 am] BILLING CODE 4910-13-P

This AD results from a report that the power feeder wire bundle of the auxiliary power unit (APU) was found touching the hydraulic system return tube during inspection of an airplane. We are issuing this AD to prevent insufficient clearance between the wire bundle and hydraulic tube that could lead to chafing of the wire bundle, which could cause arcing and a consequent hydraulic fluid fire in an area outside of the smoke detection and fire extinguishing zone; this condition could result in an uncontrolled fire on the airplane.