2014-04-06: Hydro-mechanical metering unit (HMU)

Adoption of the Amendment \n\n\n\tAccordingly, under the authority delegated to me by the Administrator, the FAA amends 14 CFR Part 39 as follows: \n\n((Page 9991)) \n\nPART 39--AIRWORTHINESS DIRECTIVES \n\n0 1. The authority citation for part 39 continues to read as follows: \n\n\n\tAuthority: 49 U.S.C. 106(g), 40113, 44701. \n\n\n\nSec. 39.13 (Amended) \n\n\n\n0 2. The FAA amends Sec. 39.13 by adding the following new airworthiness directive (AD): \n\n2014-04-06 Turbomeca S.A.: Amendment 39-17764; Docket No. FAA-2013- 0381; Directorate Identifier 2013-NE-16-AD. \n\n(a) Effective Date \n\n\n\tThis AD becomes effective March 31, 2014. \n\n(b) Affected ADs \n\n\n\tNone. \n\n(c) Applicability \n\n\n\tThis AD applies to all Turbomeca S.A. Arrius 2B1, 2B1A, 2B2, and 2K1 turboshaft engines. \n\n(d) Reason \n\n\n\tThis AD was prompted by in-flight shutdowns caused by interrupted fuel supply at the hydro-mechanical metering unit (HMU). We are issuing this AD to prevent in-flight shutdown and damage to the engine. \n\n(e) Actions and Compliance \n\n\n\tComply with this AD within the compliance times specified, unless already done. \n\n(f) Initial Visual Inspection for HMUs Not Previously Inspected \n\n\n\t(1) On the effective date of this AD, for those HMUs that have not previously been inspected using Turbomeca Mandatory Service Bulletin (MSB) No. SB 319 73 2825, Version G, dated January 24, 2013, or earlier versions; perform an initial visual inspection of the HMU high-pressure pump drive gear shaft splines for wear, corrosion, scaling, or cracks, and clean and inspect the sleeve assembly splines for wear, corrosion, scaling, or cracks, at the following: \n\t(i) For HMUs that have accumulated more than 150 operating hours (OHs) since new or since last overhaul, within 50 HMU OHs after effective date of this AD. \n\t(ii) For HMUs that have accumulated 150 or fewer OHs since new or since last overhaul, before exceeding 200 HMU OHs. \n\n\n\t(g) Initial Visual Inspection for HMUs That Have Been Previously Inspected \n\n\n\t(1) On the effective date of this AD, for those HMUs that have been previously inspected per Turbomeca MSB No. SB 319 73 2825, Version G, dated January 24, 2013, or earlier versions; perform a visual inspection of HMU aft splines of the high pressure pump for wear, corrosion, scaling, or cracks, and clean and inspect the sleeve assembly splines for wear, corrosion, scaling, or cracks, at the following: \n\t(i) For HMUs that have accumulated 300 OHs or more since last inspection, within 200 HMU OHs after effective date of this AD. \n\t(ii) For HMUs that have accumulated fewer than 300 OHs since last inspection, before exceeding 500 HMU OHs. \n\n(h) Repetitive Visual Inspections of HMUs \n\n\n\t(1) Thereafter, repetitively visually inspect the HMU aft splines of the high pressure pump, and clean and inspect the sleeve assembly splines for wear, corrosion, scaling, or cracks, at intervals not to exceed 500 HMU OHs. \n\t(2) If, during any initial or repetitive inspection required by this AD, an HMU does not pass inspection, then before further flight, replace the sleeve assembly on the affected high pressure pump drive gear shaft or replace the affected HMU. \n\n(i) Installation Prohibition \n\n\n\tAfter the effective date of this AD, do not install any engine on any helicopter unless the HMU was inspected as required by this AD. \n\n(j) Alternative Methods of Compliance (AMOCs) \n\n\n\tThe Manager, Engine Certification Office, FAA, may approve AMOCs to this AD. Use the procedures found in 14 CFR 39.19 to make your request. \n\n(k) Related Information \n\n\n\t(1) For more information about this AD, contact Anthony W. Cerra, Jr., Aerospace Engineer, Engine Certification Office, FAA, Engine & Propeller Directorate, 12 New England Executive Park, Burlington, MA 01803; email: anthony.cerra@faa.gov; phone: 781-238- 7128; fax: 781-238-7199. \n\t(2) Refer to MCAI European Aviation Safety Agency, AD 2013-0082, dated April 2, 2013, for more information. You may examine the MCAI in the AD docket on the Internet at http://www.regulations.gov/#!documentDetail;D=FAA-2013-0381-0004. \n\t(3) Turbomeca MSB No. SB 319 73 2825, Version G, dated January 24, 2013, which is not incorporated by reference in this AD, can be obtained from Turbomeca, S.A. using the contact information in paragraph (k)(4) of this AD. \n\t(4) For service information identified in this AD, contact Turbomeca, S.A., 40220 Tarnos, France; phone: 33 (0)5 59 74 40 00; telex: 570 042; fax: 33 (0)5 59 74 45 15. \n\t(5) You may view this service information at the FAA, Engine & Propeller Directorate, 12 New England Executive Park, Burlington, MA. For information on the availability of this material at the FAA, call 781-238-7125. \n\n(l) Material Incorporated by Reference \n\n\n\tNone.