EASA AD No.: 2010-0101R2 

EASA Form 110 Page 1/4

EASA AIRWORTHINESS DIRECTIVE 

AD No.: 2010-0101R2 

Date: 24 March 2011 

Note: This 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 

Revision : This AD revises EASA AD 2010-0101R1 dated 04 August 2010. 

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 post-TU347 

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. 

After issuance of AD 2010-0101-E, Turboméca has introduced a reinforced 

Eddy-current inspection which provides a lower (improved) detection 

threshold of the metallurgical non-conformities. This reinforced Eddy-current 
EASA AD No.: 2010-0101R2 

EASA Form 110 Page 2/4

inspection, named “CFR”, combined with a revised analysis, allowed to 

increase the life limit of the post-TU347 GG second Stage Turbine Discs 

identified as “CFR” over the 2 500 GG life cycles of the “non-CFR” Discs, as 

specified in AD 2010-0101R1. 

The revision 2 of this AD is issued to increase further the life limit of the 

post-TU347 GG 2nd stage turbine discs identified as “CFR” and the life limit 

of the post-TU347 GG 2nd stage turbine discs identified as “non-CFR”. This 

is possible as, since issuance of AD 2010-0101R1, Turboméca has carried 

out further analysis and testing on those discs. 

Effective Date: Revision 2: 07 April 2011 

Revision 1: 18 August 2010 

Original Issue: 06 June 2010 

Required Action(s) 

and Compliance 

Time(s): 

Required as indicated, unless accomplished previously:

(1) For “non-CFR” (see Note [a]) second Stage Turbine Discs, 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 C. 

Table 1: 

“non-CFR” [a] 

Second Stage Turbine Disc 

Accumulated GG cycles at the 

effective date of this AD: 

Compliance time: 

4 000 or more 20 GG cycles after the effective 

date of this AD 

Less than 4 000 Upon accumulating 4 000 GG 

cycles 

Note [a]: “non-CFR” second Stage Turbine Discs were not subject to the 

reinforced Eddy-current inspection. These parts are not marked with 

“CFR”. P/N may only be 0 292 25 040 0. 

(2) For “CFR” (see Note [b]) GG second Stage Turbine Discs, the approved 

life is defined in the latest update of 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. The references of the Engine 

Maintenance Manuals are in Appendix of this AD (French / English 

versions). At the issue date of this AD, the approved life of the “CFR” GG 

second Stage Turbine Disc is 6 500 GG cycles. 

Note [b]: “CFR” second Stage Turbine Discs were subject to the 

reinforced Eddy-current inspection. These parts are permanently marked

with “CFR” next to the Part Number (P/N). P/N may be 0 292 25 040 0 or 

7 292 25 040 1. 

(3) In a Repair Center, a “non-CFR” second Stage Turbine Disc removed 

from service may be sent to an approved facility to be subject to a 

reinforced Eddy-current inspection in accordance with Paragraph 2.B.(2) 

of Turboméca MSB A292 72 0831 version C. The discs that will pass the 

inspection will be marked “CFR” and the remaining life will be the 

approved life defined in Paragraph (2) of this AD minus the number of 

consumed cycles of the part, in accordance with Paragraph 2.D.(3) of 

Turboméca MSB A292 72 0831 version C. 

(4) Compliance with the requirements of paragraph (1), (2) and (3) of this AD 

can be demonstrated by: 

(4.1)Revising as follows, unless accomplished previously, the approved 
EASA AD No.: 2010-0101R2 

EASA Form 110 Page 3/4

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 limits of the GG second Stage Turbine 

Disc specified in Turboméca MSB A292 72 0831 version C. 

 and 

(4.2) Complying with the approved Aircraft Maintenance Programme as 

described in paragraph (4.1) of this AD. 

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

Stage Turbine Disc unless in compliance with the requirements of this 

AD. 

Ref. Publications: Turboméca Mandatory Service Bulletin A292 72 0831 version C dated 03 

March 2011. 

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 required actions and the risk allowance have granted the issuance 

of a Final AD with Request for Comments, postponing the public 

consultation process after publication. 

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: 

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.
EASA AD No.: 2010-0101R2 

EASA Form 110 Page 4/4

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