AD 2005-20-40 Airworthiness Directives; Boeing Model 757-200, -200CB, and -200PF Series Airplanes

Models named: 757-200, -200CB, -200PF series. Read the applicability below — it usually turns on serial or part numbers too.

This AD applies to Boeing Model 757-200, -200CB, and -200PF series airplanes, certificated in any category, as identified in Boeing Special Attention Service Bulletin 757-27-0150, 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. Inspection To Determine Part Number and Serial Number (f) Within 60 months after the effective date of this AD: Do an inspection of each trailing edge flap transmission assembly to determine the part number (P/N) and serial number (S/N) and any applicable related investigative and corrective actions and part marking, by accomplishing all of the applicable actions specified in the Accomplishment Instructions of Boeing Special Attention Service Bulletin 757-27-0150, dated December 9, 2004. If, during any related investigative action, any transmission output gear is found with a defect or crack, before further flight, replace that transmission output gear or replace the entire flap transmission assembly with a new or serviceable flap transmission assembly. Operators should note that, instead of the P/N and S/N inspection required by this AD, a review of airplane maintenance records for any trailing edge flap transmission assembly is considered acceptable if the P/N and S/N of that assembly can be conclusively determined from that review. Parts Installation (g) As of the effective date of this AD, no person may install a trailing edge flap transmission assembly, P/N 251N4050-37, -38, -39, or -40 or P/N 251N4022-28, -29, -30, or -31; having any S/N 001 through 325 inclusive; on any airplane; unless the transmission assembly has been inspected, and any applicable related investigative and corrective actions and part marking has been accomplished, in accordance with the Accomplishment Instructions of Boeing Special Attention Service Bulletin 757-27-0150, dated December 9, 2004. 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 14 CFR 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 Special Attention Service Bulletin 757-27-0150, 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 Docket Management Facility, U.S. Department of Transportation, 400 Seventh Street SW., room PL-401, Nassif Building, Washington, DC; on the Internet at http://dms.dot.gov; 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 September 30, 2005. Ali Bahrami, Manager, Transport Airplane Directorate, Aircraft Certification Service. [FR Doc. 05-20265 Filed 10-12-05; 8:45 am] BILLING CODE 4910-13-P

This AD was prompted by a report indicating that cracked flap transmission output gears have been discovered during routine overhaul of the trailing edge flap transmission assemblies. We are issuing this AD to prevent an undetected flap skew, which could result in a flap loss, damage to adjacent airplane systems, and consequent reduced controllability of the airplane.