AD 2009-04-09 Airworthiness Directives; Viking Air Limited Model DHC-6-1, DHC- 6-100, DHC-6-200, and DHC-6-300 Airplanes

Models named: DHC-6-1, DHC-6-100, DHC-6-200, DHC-6-300. Read the applicability below — it usually turns on serial or part numbers too.

This AD applies to the following Models DHC-6-1, DHC-6-100, DHC-6-200, and DHC-6-300 airplanes, all serial numbers, that are certificated in any category: (1) Group 1: Equipped with wing boxes, part numbers (P/Ns) C6W1002-1, C6W1002-3, WR6-1002-59 or WR6-1002-61 that incorporate a P/N C6WM1027-1 front spar adapter assembly with 10 or more years of service; and (2) Group 2: Equipped with wing boxes, P/Ns C6W1002-5, C6W1002-7, C6W1002-9, C6W1002-11, C6W1002-13, C6W1002-15, C6W1002-17, C6W1002-19, C6W1002-21, C6W1002-23, C6W1002-51, C6W1002-53, C6W1002-55, C6W1002-57 or C6W1002-61 that incorporate a P/N C6WM1027-1 front spar adapter assembly with 10 or more years of service.

Unless already done, do the following actions: (1) For Group 1 airplanes, within the next 180 days after August 5, 2008 (the effective date of AD 2008-11-10), install inspection holes in the left-hand (LH) and right-hand (RH) lower wing skins following Viking DHC-6 Twin Otter Service Bulletin Number V6/541, dated October 1, 2007. (2) For Group 2 airplanes, within the next 180 days after the effective date of this AD, install inspection holes in the LH and RH lower wing skins following Viking DHC-6 Twin Otter Service Bulletin Number V6/541, dated October 1, 2007. (3) For Group 1 and Group 2 airplanes, before further flight after installing the inspection holes required in paragraph (f)(1) or (f)(2) of this AD, initially inspect the LH and RH front spar adapter assemblies for cracks, and repetitively thereafter inspect all affected wing box P/Ns at intervals not to exceed 1,200 hours time-in-service or 12 months, whichever occurs first, until the replacement required in paragraph (f)(4) of this AD is done. (i) For wing box P/Ns C6W1002-1, C6W1002-3, C6W1002-5, C6W1002-7, C6W1002-9, C6W1002-11, C6W1002-13, C6W1002-15, C6W1002-17, C6W1002-19, C6W1002-21, C6W1002-23, C6W1002-51, C6W1002-53, C6W1002-55, C6W1002-57, C6W1002-59, and C6W1002-61, inspect following Viking DHC-6 Twin Otter Service Bulletin Number V6/540, dated October 1, 2007. (ii) For wing box P/Ns WR6-1002-59 or WR6-1002-61, inspect following R.W. Martin, Inc. Service Bulletin No. 00160/2, Revision A, dated November 15, 2007. (4) For Group 1 and 2 airplanes, before further flight after doing any inspection required in paragraph (f)(3) of this AD where cracks are found, replace the cracked front spar adapter assembly with a front spar adapter assembly, P/N C6WM1027-3. Do the replacement following Viking DHC-6 Twin Otter Service Bulletin Number V6/542, dated October 1, 2007. This replacement terminates the repetitive inspections required in paragraph (f)(3) of this AD for the replaced front spar adapter assembly. (5) As a terminating action for the repetitive inspections required in paragraph (f)(3) of this AD, at any time after the initial inspection required in paragraph (f)(3) of this AD, you may replace P/N C6WM1027-1 with P/N C6WM1027-3, except it must be replaced prior to further flight as required by paragraph (f)(4) of this AD. FAA AD Differences Note: This AD differs from the MCAI and/or service information as follows: (1) MCAI Transport Canada AD No. CF-2007-31, dated December 17, 2007, is applicable to airplane models with front spar adapter assembly P/N C6WM1027-3 that incorporate task C57-10-18 of the DHC-6 Corrosion Prevention and Control Manual (CPCM), PSM 1-6-5. (2) The applicability of this AD does not include airplane models with front spar adapter assembly P/N C6WM1027-3 that incorporate task C57-10-18 of the DHC-6 CPCM, PSM 1-6-5, which is required in the Transport Canada AD No. CF-94-12R1, dated April 13, 1999, and AD No. CF-99-11, dated May 28, 1999. We have addressed the Corrosion Prevention and Control Program in AD 2008-13-11 (73 FR 37355, July 1, 2008), which identifies specific areas that must be inspected to ensure the structural integrity of the DHC-6 fleet. Other FAA AD Provisions (g) The following provisions also apply to this AD: (1) Alternative Methods of Compliance (AMOCs): The Manager, New York Aircraft Certification Office, 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: Pong Lee, Aerospace Engineer, FAA, New York Aircraft Certification Office, ANE-171, 1600 Stewart Avenue, Suite 410, Westbury, New York 11590; telephone: (516) 228-7324; fax: (516) 794-5531. 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. (2) Airworthy Product: For any requirement in this AD to obtain corrective actions from a manufacturer or other source, use these actions if they are FAA-approved. Corrective actions are considered FAA-approved if they are approved by the State of Design Authority (or their delegated agent). You are required to assure the product is airworthy before it is returned to service. (3) Reporting Requirements: For any reporting requirement in this AD, under the provisions of the Paperwork Reduction Act (44 U.S.C. 3501 et seq. ), the Office of Management and Budget (OMB) has approved the information collection requirements and has assigned OMB Control Number 2120-0056. Related Information (h) Refer to MCAI Transport Canada AD No. CF-2007-31, dated December 17, 2007; Viking DHC-6 Twin Otter Service Bulletins No. V6/540, dated October 1, 2007; No. V6/541, dated October 1, 2007; and No. V6/542, dated October 1, 2007; and R.W. Martin, Inc. Service Bulletin No. 00160/2, Revision A, dated November 15, 2007, for related information. Material Incorporated by Reference (i) You must use Viking DHC-6 Twin Otter Service Bulletins No. V6/540, dated October 1, 2007; No. V6/541, dated October 1, 2007; and No. V6/542, dated October 1, 2007; and R.W. Martin, Inc. Service Bulletin No. 00160/2, Revision A, dated November 15, 2007, to do the actions required by this AD, unless the AD specifies otherwise. (1) On August 5, 2008 (73 FR 37353, July 1, 2008), the Director of the Federal Register previously approved the incorporation by reference of Viking DHC-6 Twin Otter Service Bulletins No. V6/540, dated October 1, 2007; No. V6/541, dated October 1, 2007; and No. V6/542, dated October 1, 2007; and R.W. Martin, Inc. Service Bulletin No. 00160/2, Revision A, dated November 15, 2007. (2) For service information identified in this AD, contact Viking Air Limited, 9574 Hampden Road, Sidney, B.C., Canada V8L 5V5; telephone: (250) 656-7227; fax: (250) 656-0673; Internet: http://www.vikingair.com ; or R.W. Martin, Inc., 37552 Winchester Road, Hangar 20, Murrieta, California 92563; telephone: (951) 600-0009; fax: (951) 600-1005; Internet: http://www.rwmi.net. (3) You may review copies of the service information incorporated by reference for this AD at the FAA, Central Region, Office of the Regional Counsel, 901 Locust, Kansas City, Missouri 64106. For information on the availability of this material at the Central Region, call (816) 329-3768. (4) You may also review copies of the service information incorporated by reference for this AD 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 Kansas City, Missouri, on February 6, 2009. Kim Smith, Manager, Small Airplane Directorate, Aircraft Certification Service. [FR Doc. E9-3115 Filed 2-18-09; 8:45 am] BILLING CODE 4910-13-P

Unless already done, do the following actions: (1) For Group 1 airplanes, within the next 180 days after August 5, 2008 (the effective date of AD 2008-11-10), install inspection holes in the left-hand (LH) and right-hand (RH) lower wing skins following Viking DHC-6 Twin Otter Service Bulletin Number V6/541, dated October 1, 2007. (2) For Group 2 airplanes, within the next 180 days after the effective date of this AD, install inspection holes in the LH and RH lower wing skins following Viking DHC-6 Twin Otter Service Bulletin Number V6/541, dated October 1, 2007. (3) For Group 1 and Group 2 airplanes, before further flight after installing the inspection holes required in paragraph (f)(1) or (f)(2) of this AD, initially inspect the LH and RH front spar adapter assemblies for cracks, and repetitively thereafter inspect all affected wing box P/Ns at intervals not to exceed 1,200 hours time-in-service or 12 months, whichever occurs first, until the replacement required in paragraph (f)(4) of this AD is done. (i) For wing box P/Ns C6W1002-1, C6W1002-3, C6W1002-5, C6W1002-7, C6W1002-9, C6W1002-11, C6W1002-13, C6W1002-15, C6W1002-17, C6W1002-19, C6W1002-21, C6W1002-23, C6W1002-51, C6W1002-53, C6W1002-55, C6W1002-57, C6W1002-59, and C6W1002-61, inspect following Viking DHC-6 Twin Otter Service Bulletin Number V6/540, dated October 1, 2007. (ii) For wing box P/Ns WR6-1002-59 or WR6-1002-61, inspect following R.W. Martin, Inc. Service Bulletin No. 00160/2, Revision A, dated November 15, 2007. (4) For Group 1 and 2 airplanes, before further flight after doing any inspection required in paragraph (f)(3) of this AD where cracks are found, replace the cracked front spar adapter assembly with a front spar adapter assembly, P/N C6WM1027-3. Do the replacement following Viking DHC-6 Twin Otter Service Bulletin Number V6/542, dated October 1, 2007. This replacement terminates the repetitive inspections required in paragraph (f)(3) of this AD for the replaced front spar adapter assembly. (5) As a terminating action for the repetitive inspections required in paragraph (f)(3) of this AD, at any time after the initial inspection required in paragraph (f)(3) of this AD, you may replace P/N C6WM1027-1 with P/N C6WM1027-3, except it must be replaced prior to further flight as required by paragraph (f)(4) of this AD. FAA AD Differences Note: This AD differs from the MCAI and/or service information as follows: (1) MCAI Transport Canada AD No. CF-2007-31, dated December 17, 2007, is applicable to airplane models with front spar adapter assembly P/N C6WM1027-3 that incorporate task C57-10-18 of the DHC-6 Corrosion Prevention and Control Manual (CPCM), PSM 1-6-5. (2) The applicability of this AD does not include airplane models with front spar adapter assembly P/N C6WM1027-3 that incorporate task C57-10-18 of the DHC-6 CPCM, PSM 1-6-5, which is required in the Transport Canada AD No. CF-94-12R1, dated April 13, 1999, and AD No. CF-99-11, dated May 28, 1999. We have addressed the Corrosion Prevention and Control Program in AD 2008-13-11 (73 FR 37355, July 1, 2008), which identifies specific areas that must be inspected to ensure the structural integrity of the DHC-6 fleet. Other FAA AD Provisions (g) The following provisions also apply to this AD: (1) Alternative Methods of Compliance (AMOCs): The Manager, New York Aircraft Certification Office, 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: Pong Lee, Aerospace Engineer, FAA, New York Aircraft Certification Office, ANE-171, 1600 Stewart Avenue, Suite 410, Westbury, New York 11590; telephone: (516) 228-7324; fax: (516) 794-5531. 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. (2) Airworthy Product: For any requirement in this AD to obtain corrective actions from a manufacturer or other source, use these actions if they are FAA-approved. Corrective actions are considered FAA-approved if they are approved by the State of Design Authority (or their delegated agent). You are required to assure the product is airworthy before it is returned to service. (3) Reporting Requirements: For any reporting requirement in this AD, under the provisions of the Paperwork Reduction Act (44 U.S.C. 3501 et seq. ), the Office of Management and Budget (OMB) has approved the information collection requirements and has assigned OMB Control Number 2120-0056. Related Information (h) Refer to MCAI Transport Canada AD No. CF-2007-31, dated December 17, 2007; Viking DHC-6 Twin Otter Service Bulletins No. V6/540, dated October 1, 2007; No. V6/541, dated October 1, 2007; and No. V6/542, dated October 1, 2007; and R.W. Martin, Inc. Service Bulletin No. 00160/2, Revision A, dated November 15, 2007, for related information. Material Incorporated by Reference (i) You must use Viking DHC-6 Twin Otter Service Bulletins No. V6/540, dated October 1, 2007; No. V6/541, dated October 1, 2007; and No. V6/542, dated October 1, 2007; and R.W. Martin, Inc. Service Bulletin No. 00160/2, Revision A, dated November 15, 2007, to do the actions required by this AD, unless the AD specifies otherwise. (1) On August 5, 2008 (73 FR 37353, July 1, 2008), the Director of the Federal Register previously approved the incorporation by reference of Viking DHC-6 Twin Otter Service Bulletins No. V6/540, dated October 1, 2007; No. V6/541, dated October 1, 2007; and No. V6/542, dated October 1, 2007; and R.W. Martin, Inc. Service Bulletin No. 00160/2, Revision A, dated November 15, 2007. (2) For service information identified in this AD, contact Viking Air Limited, 9574 Hampden Road, Sidney, B.C., Canada V8L 5V5; telephone: (250) 656-7227; fax: (250) 656-0673; Internet: http://www.vikingair.com ; or R.W. Martin, Inc., 37552 Winchester Road, Hangar 20, Murrieta, California 92563; telephone: (951) 600-0009; fax: (951) 600-1005; Internet: http://www.rwmi.net. (3) You may review copies of the service information incorporated by reference for this AD at the FAA, Central Region, Office of the Regional Counsel, 901 Locust, Kansas City, Missouri 64106. For information on the availability of this material at the Central Region, call (816) 329-3768. (4) You may also review copies of the service information incorporated by reference for this AD 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 Kansas City, Missouri, on February 6, 2009. Kim Smith, Manager, Small Airplane Directorate, Aircraft Certification Service. [FR Doc. E9-3115 Filed 2-18-09; 8:45 am] BILLING CODE 4910-13-P