2007-10-07: HP/LP pump assembly drive shaft

2007-10-07 Turbomeca: Amendment 39-15048.; Docket No. FAA-2005- 23809; Directorate Identifier 2005-NE-52-AD. Effective Date (a) This airworthiness directive (AD) becomes effective May 29, 2007. Affected ADs (b) This AD supersedes AD 2006-21-10. Applicability (c) This AD applies to Turbomeca Arriel 2B, 2B1, and 2B1A turboshaft engines. These engines are installed on, but not limited to, Eurocopter AS350B3 and EC130B4 helicopters. Reason (d) European Aviation Safety Agency (EASA) AD No. 2007-0044, dated April 27, 2007, states: The deterioration of the splines on the HP/LP pump assembly drive shaft may eventually interrupt fuel supply and cause uncommanded in-flight engine shutdown. The result may be an emergency autorotation landing or, at worst, an accident. Two cases of in-flight shutdown resulting from splines deterioration have been reported for the ARRIUS 2B1 engine, which has the same HP/LP pump drive design as the ARRIEL 2. These cases prompted us to require the inspection at 500 hours and each time the HMU is removed/installed. This AD modifies the content of the previous DGAC France AD F- 2005-188 (EASA Approval Number 2005-6408) in adding a one time inspection within 30 operating hours from effective date of this AD as well as HMU re-installation according to a maintenance task modified to avoid this kind of wrong assembly. This has been set up following a one case of improper clipping of the coupling shaft onto the drive gear shaft, which resulted in an uncommanded in-flight engine shutdown (on a twin engine rotorcraft). This precaution measure has been taken only on engines powering single engine rotorcraft. Actions and Compliance (e) Unless already done, do the following actions. (f) Perform an initial visual inspection of the splines of the coupling assembly and the high pressure (HP) pump drive gear shaft for wear. Use 2.A. through 2.C.(2) of the Instructions to be Incorporated of Turbomeca Mandatory Service Bulletin (MSB) No. 292 73 2812, Update No. 4, dated January 2, 2007, as follows: (1) Inspect within 30 hours-in-service from the effective date of this AD for engines that were previously inspected using Update 2 of MSB 292 73 2812. (2) For engines that were not previously inspected using Update 2 of MSB 292 73 2812, inspect as follows: (i) Inspect within 50 hours-in-service after the effective date of this AD for hydraulic mechanical units (HMUs) that have accumulated 450 or more hours time-since-new (TSN) or time-since- overhaul (TSO) on the effective date of this AD. Replace the HMU if worn beyond limits. (ii) Inspect after accumulating 450 hours TSN or TSO, but before accumulating 500 hours TSN or TSO for HMUs that have fewer than 450 hours TSN or TSO on the effective date of this AD. Replace the HMU if worn beyond limits. Repetitive Visual Inspections (g) Thereafter, perform a visual inspection of the splines of the coupling shaftassembly and the HP pump drive gear shaft for wear every time you remove the HMU. Use 2.A. through 2.C.(2) of the Instructions to be Incorporated of Turbomeca MSB No. 292 73 2812, Update No. 4, dated January 2, 2007. Replace the HMU and coupling shaft assembly if worn beyond limits. FAA AD Differences (h) None. Other FAA AD Provisions (i) The following provisions also apply to this AD: (1) Alternative Methods of Compliance (AMOCs): The Manager, Engine Certification Office, FAA, has the authority to approve AMOCs for this AD, if requested using the procedures found in 14 CFR 39.19. (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, the Office of Management and Budget (OMB) has approved the information collection requirements and has assigned OMB Control Number 2120- 0056. Related Information (j) Refer to European Aviation Safety Agency AD 2007-0044, dated February 27, 2007, for related information. (k) Contact Christopher Spinney, Aerospace Engineer, Engine Certification Office, FAA, Engine and Propeller Directorate, 12 New England Executive Park, Burlington, MA 01803; e-mail: [email protected]; telephone (781) 238-7175; fax (781) 238-7199, for more information about this AD. Material Incorporated by Reference (l) You must use Turbomeca Mandatory Service Bulletin No. 292 73 2812, Update No. 4, dated January 2, 2007, to do the actions required by this AD, unless the AD specifies otherwise. (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 Turbomeca, 40220 Tarnos--France; Tel (33) 05 59 74 40 00; Telex 570 042; Fax (33) 05 59 74 45 15. (3) You may review copies at the FAA, New England Region, Office of the Regional Counsel, 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 .