AD 2010-17-11 Airworthiness Directives; Dowty Propellers R408/6-123-F/17 Model Propellers

Makes named: dowty. Read the applicability below — it usually turns on serial or part numbers too.

This AD applies to Dowty Propellers R408/6-123-F/17 model propellers. These propellers are installed on, but not limited to, Bombardier, Inc. (formerly de Havilland Canada) models DHC-8-400, DHC-8-401, and DHC-8-402 series airplanes. Reason (d) This AD results from mandatory continuing airworthiness information (MCAI) issued by an aviation authority of another country to identify and correct an unsafe condition on an aviation product. We are issuing this AD to prevent an in-flight double generator failure, which could result in reduced controllability of the airplane.

Unless already done, do the following actions. (1) For R408/6-123-F/17 model propellers with a hub, actuator, and backplate assembly line-replaceable unit serial numbers below DAP0347, do the following initial sealant application within 5,000 flight hours (FH) after the effective date of this AD: (i) Apply sealant between the bus bar assemblies and the backplate assembly. (ii) Use paragraph 3 of the Accomplishment Instructions of Dowty Propellers Alert Service Bulletin No. D8400-61-A66, Revision 5, dated June 16, 2010, to do the sealant application. (2) Thereafter, for all R408/6-123-F/17 model propellers, re-apply sealant as specified in paragraphs (e)(1)(i) through (e)(1)(ii) within every additional 10,000 FH. Installation Prohibition (3) After modification of all propellers on an airplane as required by paragraph (e)(1) of this AD, do not install any Dowty R408/6-123-F/17 propeller on that airplane unless sealant has been applied between the bus bar assemblies and the backplate assembly of that propeller using the requirements of this AD. FAA AD Differences (f) None. Previous Credit (g) Sealant application performed before the effective date of this AD using Dowty Propellers Service Bulletin No. D8400-61-66, dated February 9, 2007, Revision 1, dated May 4, 2007, Alert Service Bulletin No. D8400-61-A66, Revision 2, dated August 19, 2009, Revision 3, dated November 10, 2009, Revision 4, dated January 19, 2010, or Revision 5, dated June 16, 2010, satisfies the initial sealant application requirement of this AD. Alternative Methods of Compliance (AMOCs) (h) The Manager, Boston Aircraft Certification Office, FAA, has the authority to approve AMOCs for this AD, if requested using the procedures found in 14 CFR 39.19. Related Information (i) Refer to EASA AD 2009-0114, dated May 28, 2009, for related information. (j) Contact Michael Schwetz, Aerospace Engineer, Boston Aircraft Certification Office, FAA, Engine and Propeller Directorate, 12 New England Executive Park, Burlington, MA 01803; e-mail: michael.schwetz@faa.gov; telephone (781) 238-7761; fax (781) 238-7170, for more information about this AD. Material Incorporated by Reference (k) You must use Dowty Propellers Alert Service Bulletin No. D8400-61-A66, Revision 5, dated June 16, 2010, to do the actions required by this AD. (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 Dowty Propellers, Anson Business Park, Cheltenham Road East, Gloucester GL 29QN, UK; telephone: 44 (0) 1452 716000; fax: 44 (0) 1452 716001. (3) You may review copies at the FAA, New England Region, 12 New England Executive Park, Burlington, MA; 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/cfr/ibr-locations.html. Issued in Burlington, Massachusetts, on August 5, 2010. Peter A. White, Assistant Manager, Engine and Propeller Directorate, Aircraft Certification Service. [FR Doc. 2010-20707 Filed 8-20-10; 8:45 am] BILLING CODE 4910-13-P

Unless already done, do the following actions. (1) For R408/6-123-F/17 model propellers with a hub, actuator, and backplate assembly line-replaceable unit serial numbers below DAP0347, do the following initial sealant application within 5,000 flight hours (FH) after the effective date of this AD: (i) Apply sealant between the bus bar assemblies and the backplate assembly. (ii) Use paragraph 3 of the Accomplishment Instructions of Dowty Propellers Alert Service Bulletin No. D8400-61-A66, Revision 5, dated June 16, 2010, to do the sealant application. (2) Thereafter, for all R408/6-123-F/17 model propellers, re-apply sealant as specified in paragraphs (e)(1)(i) through (e)(1)(ii) within every additional 10,000 FH. Installation Prohibition (3) After modification of all propellers on an airplane as required by paragraph (e)(1) of this AD, do not install any Dowty R408/6-123-F/17 propeller on that airplane unless sealant has been applied between the bus bar assemblies and the backplate assembly of that propeller using the requirements of this AD. FAA AD Differences (f) None. Previous Credit (g) Sealant application performed before the effective date of this AD using Dowty Propellers Service Bulletin No. D8400-61-66, dated February 9, 2007, Revision 1, dated May 4, 2007, Alert Service Bulletin No. D8400-61-A66, Revision 2, dated August 19, 2009, Revision 3, dated November 10, 2009, Revision 4, dated January 19, 2010, or Revision 5, dated June 16, 2010, satisfies the initial sealant application requirement of this AD. Alternative Methods of Compliance (AMOCs) (h) The Manager, Boston Aircraft Certification Office, FAA, has the authority to approve AMOCs for this AD, if requested using the procedures found in 14 CFR 39.19. Related Information (i) Refer to EASA AD 2009-0114, dated May 28, 2009, for related information. (j) Contact Michael Schwetz, Aerospace Engineer, Boston Aircraft Certification Office, FAA, Engine and Propeller Directorate, 12 New England Executive Park, Burlington, MA 01803; e-mail: michael.schwetz@faa.gov; telephone (781) 238-7761; fax (781) 238-7170, for more information about this AD. Material Incorporated by Reference (k) You must use Dowty Propellers Alert Service Bulletin No. D8400-61-A66, Revision 5, dated June 16, 2010, to do the actions required by this AD. (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 Dowty Propellers, Anson Business Park, Cheltenham Road East, Gloucester GL 29QN, UK; telephone: 44 (0) 1452 716000; fax: 44 (0) 1452 716001. (3) You may review copies at the FAA, New England Region, 12 New England Executive Park, Burlington, MA; 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/cfr/ibr-locations.html. Issued in Burlington, Massachusetts, on August 5, 2010. Peter A. White, Assistant Manager, Engine and Propeller Directorate, Aircraft Certification Service. [FR Doc. 2010-20707 Filed 8-20-10; 8:45 am] BILLING CODE 4910-13-P