EASA AD No.: 2012-0117

CAP.00110-001 © European Aviation Safety Agency. Al l rights reserved. 1/3 Proprietary document. Copies are not controlled. Co nfirm revision status through the EASA-Internet/Int ranet. 

## EASA AIRWORTHINESS DIRECTIVE

AD No.: 2012-0117

Date: 03 July 2012

Note: This Airworthiness Directive (AD) is issued b y EASA, acting in accordance with Regulation (EC) No 216/2008 on behalf of the European Communit y, its Member States and of the European third countries that participate in the ac tivities of EASA under Article 66 of that Regulation.

This AD is issued in accordance with EC 1702/2003, Part 21A.3B. In accordance with EC 2042/2003 Annex I, Part M.A.301, the continuing airworthiness of an aircraft shall be en sured by accomplishing any applicable ADs. Conseque ntly, no person may operate an aircraft to which an AD applies, except in accordan ce with the requirements of that AD, unless otherwi se specified by the Agency [EC 2042/2003 Annex I, Part M.A.303] or agreed with the Authority of the State of Registry [EC 216/2008, A rticle 14(4) exemption]. 

### Design Approval Holder’s Name: TURBOMÉCA Type/Model designation(s): ARRIEL 1 engines

TCDS Number: EASA.E.073

Foreign AD: Not applicable

Supersedure: None



### ATA 72 Engine – Gas Generator Rotating Assembly and Rear B earing – Check / Replacement

Manufacturer(s): Turboméca S.A.
Applicability: ARRIEL 1A1, 1A2, 1B, 1C, 1C1, 1C2, 1 D, 1D1, 1E2, 1K, 1K1, 1S and 1S1 turbo-shaft engines, all serial numbers. These engines are known to be installed on, but not limited to, Eurocopter (formerly Eurocopter France, Aerospatiale) AS 350 B , BA, BB, B1and B2, and AS 365 N, Eurocopter Deutschland (formerly Messersc hmidt-Bölkow-Blohm) MBB-BK117-C1 and -C2, AgustaWestland (formerly Agus ta) A 109 K2, and Sikorsky S-76A helicopters.
Reason: Several cases of uncommanded in-flight shut -down (IFSD) have been reported on ARRIEL 1 engines. Results of subsequent investig ations showed that some Gas Generator (GG) rear bearing failures have occur red following “Level 3” maintenance operations on the GG Assembly. Some of these maintenance operations may have created an unbalanced condition of the GG rotating assembly and, ultimately, failure of the GG rear be aring. This condition, if not detected and corrected, coul d lead to an uncommanded engine in-flight shut down and may ultimately lead to an emergency landing. Prompted by these findings, a mandatory high GG spe ed (NG) rating vibration check at the rear part of the engine has been intro duced in the chapter 05-10 Airworthiness Limitation Section (ALS) of ARRIEL 1 Maintenance Manuals. For the reasons described above, this AD requires a ccomplishment of high NG rating vibration check and depending on findings, a ccomplishment of corrective actions. After issuance of EASA PAD 12-054, it has been realised that paragraph (2) of this AD needed to be amended as th e corrective action does not necessarily require replacement of the affected Module 03 with a serviceable Module.EASA AD No.: 2012-0117

CAP.00110-001 © European Aviation Safety Agency. Al l rights reserved. 2/3 Proprietary document. Copies are not controlled. Co nfirm revision status through the EASA-Internet/Int ranet. Effective Date: 17 July 2012

Required Action(s) and Compliance Time(s): Required as indicated, unless accomplished previous ly: (1) From the effective date of this AD, following a ny Level 3 maintenance action(s) on the GG rotating assembly (Application of Maintenance Technical Instructions (MTI) reference Nr. X 292 87 451 2, or ITM Nr. X 292 87 451 1 for French version), before release to service of the engine, accomplish a high NG rating vibration check in acco rdance with the chapter 05-10 requirements of the applicable ARRIEL 1 Maintenance Manual as listed in Appendix of this AD.
Definition : Level 3 maintenance on the GG rotating assembly i s when the Module 03 is removed from the helicopter for implem entation of deep maintenance operation to be performed in accordance with applicable MTI. (2) If, during the check as required by paragraph ( 1) of this AD, a discrepancy on Module 03 is identified, before next flight, acc omplish the applicable corrective actions as specified in Chapter 71-02-10 -760-801 of applicable Arriel 1 Maintenance Manual. Following application of corrective actions, before release to service of the engine, repeat the high NG rating vibration check as required by paragraph (1) of this AD. Note: Corrective action may ultimately lead to the replacement of the affected Module 03 with a serviceable Module 03. (3) Compliance with the requirements of paragraphs (1) and (2) of this AD can be demonstrated by: (3.1) Revising as follows the approved Aircraft Mai ntenance Programme (AMP) and standard practices on the basis of which the operator or the owner ensures the continuing airworthiness of e ach operated helicopter: Incorporate the high NG rating vibration check as defined in chapter 05-10 of the applicable ARRIEL 1 Maintenance Manual
, and (3.2) Complying with the approved AMP described in paragraph (3.1) of this AD.

Ref. Publications: Turboméca ARRIEL 1 Maintenance M anuals, as listed in Appendix of this AD. The use of later approved revisions of these docume nts is acceptable for compliance with the requirements of this AD.

Remarks: 1. If requested and appropriately substantiated, EA SA can approve Alternative Methods of Compliance for this AD. 2. This AD was posted on 31 May 2012 as PAD 12-054 for consultation until 28 June 2012. No comments were received during the consultation period. 3. Enquiries regarding this AD should be referred t o the Safety Information Section, Executive Directorate, EASA. E-mail: ADs@easa.europa.eu

. 4. For any question concerning the technical conten t of the requirements in this AD, please contact: Turboméca, S.A., ARRIEL 1 Customer Support, 40220 Tarnos, France, Fax: +33 5 59 74 45 15, or contact your usual or nearest Turboméca technical r epresentative at www.turbomeca-support.com

.EASA AD No.: 2012-0117

CAP.00110-001 © European Aviation Safety Agency. Al l rights reserved. 3/3 Proprietary document. Copies are not controlled. Co nfirm revision status through the EASA-Internet/Int ranet. 

### Appendix

Maintenance Manuals according to Engine Variant, wi th initial issue/version incorporating the addition al requirement of this AD in the ALS:

Engine Variant Maintenance Manual
French Version English Version

ARRIEL 1A1 X 292 B3 452 1 Issue 13 X 292 B3 452 2 I ssue 13

ARRIEL 1A2 X 292 A9 452 1 Issue 14 X 292 A9 452 2 I ssue 14

ARRIEL 1B X 292 65 452 1 Issue 13 X 292 65 452 2 Is sue 13

ARRIEL 1C X 292 B0 452 1 Issue 14 X 292 B0 452 2 Is sue 14

ARRIEL 1C1 X 292 C3 452 1 Issue 14 X 292 C3 452 2 I ssue 14

ARRIEL 1C2 X 292 G1 452 1 Issue 14 X 292 G1 452 2 I ssue 14

ARRIEL 1D X 292 E5 452 1 Issue 14 X 292 E5 452 2 Is sue 14

ARRIEL 1D1 X 292 G2 452 1 Issue 14 X 292 G2 452 2 I ssue 14

ARRIEL 1E2 X 292 M3 452 1 Issue 14 X 292 M3 452 2 I ssue 14

ARRIEL 1K X 292 D8 452 1 Issue 14 X 292 D8 452 2 Is sue 14

ARRIEL 1K1 X 292 H3 452 1 Issue 14 X 292 H3 452 2 I ssue 14

ARRIEL 1S X 292 F9 452 1 Issue 14 X 292 F9 452 2 Is sue 14

ARRIEL 1S1 X 292 H4 452 1 Issue 14 X 292 H4 452 2 I ssue 14