EASA AD No.: 2010-0101-E 

EASA Form 111 Page 1/3

EASA EMERGENCY AIRWORTHINESS DIRECTIVE 

AD No.: 2010-0101-E 

Date: 04 June 2010 

Note: This Emergency Airworthiness Directive (AD) is issued by EASA, acting in 

accordance with Regulation (EC) No 216/2008 on behalf of the European Community, its 

Member States and of the European third countries that participate in the activities 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 ensured by accomplishing any applicable ADs. Consequently, no person 

may operate an aircraft to which an AD applies, except in accordance with the requirements of that AD unless otherwise 

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, Article 14(4) exemption]. 

Type Approval Holder’s Name : 

Turboméca 

Type/Model designation(s) : 

ARRIEL 1 series turboshaft engines 

TCDS Number : EASA.E.073 

Foreign AD : Not applicable 

Supersedure : None 

ATA 72 Engine – Module M03 (Gas Generator) – Post-TU347 Second 

Stage Turbine Disc – Reduced Life Limit 

Manufacturer(s): Turboméca S.A. 

Applicability: Arriel 1A, 1A1, 1B, 1C, 1C1, 1C2, 1D, 1D1 and 1S1 turbo-shaft engines, all 

serial numbers if modified by TU347. 

These engines are known to be installed on, but not limited to, the following 

helicopters: 

Eurocopter AS350 series, AS365 and SA365 series, Sikorsky S-76A series 

and C series. 

Reason: Metallurgical non-conformities have been found when performing quality 

inspections during production of Arriel 1 Gas Generator (GG) second Stage 

Turbine Discs introduced by Turboméca Modification TU347 (P/N 0 292 25 

040 0). Analysis has concluded that the approved life limit of the postTU347 GG second Stage Turbine Disc needs to be reduced to 2 500 GG 

cycles. 

Exceeding the revised approved life limit could result in a GG second Stage 

Turbine Disc burst with uncontained high energy debris. 

To address this unsafe condition, this AD requires compliance with the 

revised life limit of the GG second Stage Turbine Disc by removing the 

module M03 (Gas Generator) or the GG second Stage Turbine fitted with a 

GG second stage Turbine Disc which has reached or exceeded the new life 

limit. 
EASA AD No.: 2010-0101-E 

EASA Form 111 Page 2/3

Effective Date: 06 June 2010 

Required Action(s) 

and Compliance 

Time(s): 

Required as indicated, unless accomplished previously:

(1) Within the compliance time as indicated in Table 1, as applicable, 

replace the module M03 (Gas Generator) or the GG second Stage 

Turbine, in accordance with Turboméca Mandatory Service Bulletin 

(MSB) A292 72 0831 version A. 

Table 1: 

Second Stage Turbine Disc 

Accumulated GG cycles on the 

Effective Date of this AD: 

Compliance time: 

2 500 or more 20 GG cycles after the effective 

date of this AD 

Less than 2 500 Upon accumulating 2 500 GG 

cycles 

(2) Compliance with the requirements of paragraph (1) of this AD can be 

demonstrated by: 

(2.1) Revising as follows, unless accomplished previously, the 

approved Aircraft Maintenance Programme from which the 

Operator or the Owner ensures the continuing airworthiness of 

each operated helicopter, as well as the Engine log book and 

Module M03 log card: 

Incorporate the new life limit (2 500 GG cycles) of the GG second 

Stage Turbine Disc P/N 0 292 25 040 0 specified in Turboméca 

Mandatory Service Bulletin (MSB) A292 72 0831 version A. 

and 

(2.2) Complying with the approved Aircraft Maintenance Programme as 

described in paragraph (2.1) of this AD. 

(3) After the effective date of this AD, do not install a post-TU347 GG 

second Stage Turbine Disc (P/N 0 292 25 040 0) unless in compliance 

with paragraphs (1) and (2) of this AD. 

Note: For all engines fitted with post-TU347 GG second Stage Turbine 

Discs, Turboméca plans to update the Airworthiness Limitation 

Section of the Engine Maintenance Manual Chapter 05 – 

INSPECTIONS – FREQUENCIES, Chapter 05-10-03, Task 05-10-03-

900-801-A01, Par. Service Life Limits – Life Limit Values, in order to 

set the new life limit of the GG second Stage Turbine Disc P/N 0 292 

25 040 0. The references of the Engine Maintenance Manuals to be 

updated are in Appendix of this AD (French / English versions). 

Ref. Publications: Turboméca Mandatory Service Bulletin (MSB) A292 72 0831 version A 

dated 02 June 2010. 

The use of later approved revisions of this document is acceptable for 

compliance with the requirements of this AD. 

Remarks : 1. If requested and appropriately substantiated, EASA can approve 

Alternative Methods of Compliance for this AD. 

2. The safety assessment has requested not to implement the full 

consultation process and an immediate publication and notification. 

3. Enquiries regarding this AD should be referred to the Airworthiness 

Directives, Safety Management & Research Section, Certification 

Directorate, EASA. E-mail: ADs@easa.europa.eu. 

4. For any question concerning the technical content of the requirements 

in this AD, please contact: 
EASA AD No.: 2010-0101-E 

EASA Form 111 Page 3/3

Turboméca, S.A., ARRIEL 1 Customer Support, 40220 TARNOS, 

FRANCE. Fax: +33 5 59 74 45 15 or contact your nearest technical 

representative at www.turbomeca-support.com

APPENDIX 

Maintenance Manuals according to Engine Variant: 

Maintenance Manual 

Engine Variant 

French Version English Version 

ARRIEL 1A 292 01 931 n/a 

ARRIEL 1A1 X 292 B3 452 1 X 292 B3 452 2 

ARRIEL 1B X 292 65 452 1 X 292 65 452 2 

ARRIEL 1C X 292 B0 452 1 X 292 B0 452 2 

ARRIEL 1C1 X 292 C3 452 1 X 292 C3 452 2 

ARRIEL 1C2 X 292 G1 452 1 X 292 G1 452 2 

ARRIEL 1D X 292 E5 452 1 X 292 E5 452 2 

ARRIEL 1D1 X 292 G2 452 1 X 292 G2 452 2 

ARRIEL 1S1 X 292 H4 452 1 X 292 H4 452 2