AD 2007-04-10 Airworthiness Directives; Boeing Model 747-400 Series Airplanes

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

This AD applies to Boeing Model 747-400 series airplanes, certificated in any category, as identified in Boeing Alert Service Bulletin 747-25A3353, dated December 9, 2004.

You are responsible for having the actions required by this AD performed within the compliance times specified, unless the actions have already been done. New Requirements of This AD Modification or Replacement, as Applicable (f) Within 48 months after the effective date of this AD: Modify the decompression panels on the smoke barrier or replace the smoke barrier with an improved smoke barrier, by accomplishing all of the actions specified in Work Package 1 of the Accomplishment Instructions of Boeing Alert Service Bulletin 747-25A3353, dated December 9, 2004, as applicable. Repetitive Inspection (g) Within 20 months or 6,000 flight hours after accomplishing the actions in paragraph (f) of this AD, whichever occurs first: Do a general visual inspection of the decompression (vent) panels on the smoke barrier for any changes from their installed condition, and do all corrective actions before further flight after the inspection, by accomplishing all of the actions specified in Work Package 2 of the Accomplishment Instructions of Boeing Alert Service Bulletin 747-25A3353, dated December 9, 2004, as applicable. Repeat the inspection thereafter at intervals not to exceed 20 months or 6,000 flight hours, whichever occurs first. Note 1: For the purposes of this AD, a general visual inspection is: “A visual examination of an interior or exterior area, installation, or assembly to detect obvious damage, failure, or irregularity. This level of inspection is made from within touching distance unless otherwise specified. A mirror may be necessary to ensure visual access to all surfaces in the inspection area. This level of inspection is made under normally available lighting conditions such as daylight, hangar lighting, flashlight, or droplight and may require removal or opening of access panels or doors. Stands, ladders, or platforms may be required to gain proximity to the area being checked.” 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) Before using any AMOC approved in accordance with § 39.19 on any airplane to which the AMOC applies, notify the appropriate principal inspector in the FAA Flight Standards Certificate Holding District Office. Material Incorporated by Reference (i) You must use Boeing Alert Service Bulletin 747-25A3353, dated December 9, 2004, to perform the actions that are required by this AD, unless the AD specifies otherwise. The Director of the Federal Register approved the incorporation by reference of this document in accordance with 5 U.S.C. 552(a) and 1 CFR part 51. Contact Boeing Commercial Airplanes, P.O. Box 3707, Seattle, Washington 98124-2207, for a copy of this service information. You may review copies 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 the NARA, call (202) 741-6030, or go to: http://www.archives.gov/federal-register/cfr/ibr-locations.html. Issued in Renton, Washington, on February 6, 2007. Ali Bahrami, Manager, Transport Airplane Directorate, Aircraft Certification Service. [FR Doc. E7-2511 Filed 2-15-07; 8:45 am] BILLING CODE 4910-13-P

This AD results from reports of decompression panels on the smoke barrier opening in flight and on the ground without a decompression event. We are issuing this AD to prevent inadvertent opening or tearing of decompression panels, which could result in degraded cargo fire detection and suppression capability, smoke penetration into an occupied compartment, and an uncontrolled cargo fire, if a fire occurs in the main deck cargo compartment.