AD 2011-24-07 Airworthiness Directives; Turbomeca S.A. Arriel 2B Turboshaft Engines

This AD applies to Turbomeca Arriel 2B turboshaft engines with a hydromechanical unit (HMU) that has a part number (P/N) and serial number (S/N) listed in Table 1 of this AD installed. Table 1—Affected HMUs P/Ns S/Ns 0292860750 1008B 0292860750 1068B 0292860750 1142B 0292860750 1143B 0292860750 1183B 0292860750 1230B 0292860750 272B 0292860750 275B 0292860750 342B 0292860750 363B 0292860750 422B 0292860750 436B 0292860750 499B 0292860750 524B 0292860750 536B 0292860750 560B 0292860750 598B 0292860750 606B 0292860750 647B 0292860750 652B 0292860750 716B 0292860750 749B 0292860750 763B 0292860750 806B 0292860750 830B 0292860750 861B 0292860750 944B 0292860750 967B 0292861020 632B 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. The MCAI describes the unsafe condition as: Non-conformities on adjustment of some hydromechanical units (HMUs) have been reported by a Turbomeca repair centre. The technical investigations carried out by Turbomeca are showing that only a limited number of HMUs are potentially affected by this non-conformity to HMU adjustment. Twenty nine HMUs have been identified with potential non-conformities in the proper adjustment of the metering valve. The exact location of these 29 HMUs is unknown. We are issuing this AD to prevent an uncommanded inflight shutdown, which could result in an emergency autorotation landing.

Unless already done, do the following actions. (f) Before further flight, perform a one-time functional test of the engine to confirm proper engine operation. This one-time functional test is not a normal engine run-up test. Use the instructions in paragraph 2.B.(1)(a) of Turbomeca Alert Mandatory Service Bulletin No. A292 73 2841, Version A, dated July 4, 2011, to perform the functional test. (1) If the engine fails the functional test, replace the HMU with an HMU eligible for installation. (2) If the engine passes the functional test, do the following: (i) Within four months after the effective date of this AD, install software modification TU143 on the Engine Electronic Control Unit of the engine. Use paragraph 2.B. of Turbomeca Service Bulletin No. 292 73 2143, dated July 24, 2007 to do the installation; and (ii) Within 12 months after the effective date of this AD, replace the HMU with an HMU eligible for installation. Definition (g) For the purpose of this AD, an HMU eligible for installation is defined as one with a serial number not listed in Table 1 of this AD, or, an HMU that passed when tested using Turbomeca Service Bulletin No. 292 73 2840. FAA AD Differences (h) None. Alternative Methods of Compliance (AMOCs) (i) The Manager, Engine Certification Office, FAA, may approve AMOCs for this AD. Use the procedures found in 14 CFR 39.19 to make your request. Related Information (j) Refer to MCAI Airworthiness Directive 2011-0128-E, dated July 6, 2011, for related information. (k) Contact Mark Riley, Aerospace Engineer, Engine Certification Office, FAA, Engine & Propeller Directorate, 12 New England Executive Park, Burlington, MA 01803; phone: (781) 238-7758; fax: (781) 238-7199, email: mark.riley@faa.gov; for more information about this AD. Material Incorporated by Reference (l) You must use the following service information to do the actions required by this AD, unless the AD specifies otherwise. The Director of the Federal Register approved the incorporation by reference (IBR) under 5 U.S.C. 552(a) and 1 CFR part 51 of the following service information on the date specified: (1) Turbomeca Alert Mandatory Service Bulletin No. A292 73 2841, Version A, dated July 4, 2011, approved for IBR December 14, 2011. (2) Turbomeca Service Bulletin No. 292 73 2143, dated July 24, 2007, approved for IBR December 14, 2011. (3) For service information identified in this AD, contact Turbomeca S.A., 40220 Tarnos, France; phone: 33-05-59-74-40-00, fax: 33-05-59-74-45-15. (4) You may review copies of the service information at the FAA, New England Region, 12 New England Executive Park, Burlington, MA. For information on the availability of this material at the FAA, call (781) 238-7125. (5) You may also review copies of the service information that is incorporated by reference at the National Archives and Records Administration (NARA). For information on the availability of this material at an NARA facility, call (202) 741-6030 or go to: http://www.archives.gov/federal-register/cfr/ibr-locations.html. Issued in Burlington, Massachusetts on November 14, 2011. Peter A. White, Manager, Engine and Propeller Directorate, Aircraft Certification Service. [FR Doc. 2011-30574 Filed 11-28-11; 8:45 am] BILLING CODE 4910-13-P

Unless already done, do the following actions. (f) Before further flight, perform a one-time functional test of the engine to confirm proper engine operation. This one-time functional test is not a normal engine run-up test. Use the instructions in paragraph 2.B.(1)(a) of Turbomeca Alert Mandatory Service Bulletin No. A292 73 2841, Version A, dated July 4, 2011, to perform the functional test. (1) If the engine fails the functional test, replace the HMU with an HMU eligible for installation. (2) If the engine passes the functional test, do the following: (i) Within four months after the effective date of this AD, install software modification TU143 on the Engine Electronic Control Unit of the engine. Use paragraph 2.B. of Turbomeca Service Bulletin No. 292 73 2143, dated July 24, 2007 to do the installation; and (ii) Within 12 months after the effective date of this AD, replace the HMU with an HMU eligible for installation. Definition (g) For the purpose of this AD, an HMU eligible for installation is defined as one with a serial number not listed in Table 1 of this AD, or, an HMU that passed when tested using Turbomeca Service Bulletin No. 292 73 2840. FAA AD Differences (h) None. Alternative Methods of Compliance (AMOCs) (i) The Manager, Engine Certification Office, FAA, may approve AMOCs for this AD. Use the procedures found in 14 CFR 39.19 to make your request. Related Information (j) Refer to MCAI Airworthiness Directive 2011-0128-E, dated July 6, 2011, for related information. (k) Contact Mark Riley, Aerospace Engineer, Engine Certification Office, FAA, Engine & Propeller Directorate, 12 New England Executive Park, Burlington, MA 01803; phone: (781) 238-7758; fax: (781) 238-7199, email: mark.riley@faa.gov; for more information about this AD. Material Incorporated by Reference (l) You must use the following service information to do the actions required by this AD, unless the AD specifies otherwise. The Director of the Federal Register approved the incorporation by reference (IBR) under 5 U.S.C. 552(a) and 1 CFR part 51 of the following service information on the date specified: (1) Turbomeca Alert Mandatory Service Bulletin No. A292 73 2841, Version A, dated July 4, 2011, approved for IBR December 14, 2011. (2) Turbomeca Service Bulletin No. 292 73 2143, dated July 24, 2007, approved for IBR December 14, 2011. (3) For service information identified in this AD, contact Turbomeca S.A., 40220 Tarnos, France; phone: 33-05-59-74-40-00, fax: 33-05-59-74-45-15. (4) You may review copies of the service information at the FAA, New England Region, 12 New England Executive Park, Burlington, MA. For information on the availability of this material at the FAA, call (781) 238-7125. (5) You may also review copies of the service information that is incorporated by reference at the National Archives and Records Administration (NARA). For information on the availability of this material at an NARA facility, call (202) 741-6030 or go to: http://www.archives.gov/federal-register/cfr/ibr-locations.html. Issued in Burlington, Massachusetts on November 14, 2011. Peter A. White, Manager, Engine and Propeller Directorate, Aircraft Certification Service. [FR Doc. 2011-30574 Filed 11-28-11; 8:45 am] BILLING CODE 4910-13-P