EASA AD No.: 2010-0273R1 

EASA Form 110 Page 1/3

EASA AIRWORTHINESS DIRECTIVE 

AD No.: 2010-0273R1 

Date: 16 February 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Revision: This AD revises EASA AD 2010-0273 dated 22 December 2010 which superseded 

EASA AD 2010-0118 dated 18 June 2010. 

ATA 72 Engine – Module M03 (Gas Generator) – Second Stage

Turbine Nozzle Guide Vane – Inspection/Replacement 

Manufacturer(s): Turboméca S.A. 

Applicability: Arriel 1B turboshaft engines, if modified by TU76 or TU202, and not 

modified by TU148, and fitted with repaired second stage Nozzle Guide 

Vane. 

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

AS350 series helicopters. 

Reason: During quality inspections in repair centre some 2nd stage Nozzle Guide 

Vanes (NGVs) to be installed on pre-TU148 standard Arriel 1B were found 

not conforming to the definition. The affected parts had been repaired and 

were found drilled on the rear flange instead of the front flange. This 

configuration corresponds to 2nd stage Turbine NGVs to be installed on 

post-TU148 standard Arriel 1B engines. This non compliance may only be 

found on post-TU76 standard 2nd stage Turbine NGVs (i.e. with flexible 

hub). 

This non compliance would increase hot gas ingestion and generate an 

increase of temperature in the Gas Generator (GG) turbine rotor, potentially 

resulting in turbine damage and an uncommanded in-flight shutdown. On a 

single-engine helicopter, this could ultimately lead to an emergency 

autorotation landing. 

To detect and correct this unsafe condition, EASA AD 2010-0118 required 

accomplishing a daily check of the engine. Furthermore, it required 

contacting Turboméca for checking applicability and, if necessary, to 
EASA AD No.: 2010-0273R1 

EASA Form 110 Page 2/3

inspect the 2nd stage Turbine NGVs. If non serviceable parts were found, it 

required replacement with serviceable ones. 

It was previously known that modification TU202 was applicable only if 

TU76 was applied. However since issuance of EASA AD 2010-0118, it was 

found that some engines modified by TU202 did not explicitly have TU76 

recorded on their log cards. Therefore these engines were wrongly 

excluded from the applicability of EASA AD 2010-0118, but they may also 

contain repaired 2nd stage Turbine NGVs affected by the same condition. 

As a result, EASA AD 2010-0273 extended the applicability of EASA AD 

2010-0118 to pre-TU148 and post TU-202 Arriel 1B engines. 

This AD is revised to clarify the intent of paragraph (6) of the “Required 

Actions and Compliance Time(s)” of the AD. 

Effective Date: 

Revision 1: 02 March 2011 

Original issue: 05 January 2011 

Required Action(s) 

and Compliance 

Time(s): 

Required as indicated, unless accomplished previously:

(1) Starting from 05 January 2011 [Effective Date of EASA AD 2010-0273], 

perform a daily check (after last flight of the day) of the free rotation of 

the gas generator, the autorotation time and the absence of noise in 

accordance with Par. 2.B(1)(a)3 of MSB A292 72 0829 version B and 

applicable Arriel 1B Maintenance Manual tasks 71-02-09-760-801 and 

05-20-01-200-801. 

If during any of these daily checks, any finding is identified in 

accordance with Par. 2.B(1)(a)3 of MSB A292 72 0829 version B, no 

further engine operation is allowed. 

(2) Within 7 days after 05 January 2011 [Effective Date of EASA AD 2010-

0273], send to Turboméca a copy of module M03 log card and 

identification sheet of the engine in accordance with the Mandatory 

Service Bulletin (MSB) A292 72 0829 version B. 

(3) If Turboméca confirm that MSB A292 72 0829 version B is not

applicable to the engine, no further action is required for compliance 

with the requirements of this AD. 

(4) If Turboméca confirm that MSB A292 72 0829 version B is applicable to 

the engine, within the compliance times indicated in table 1 of this AD, 

inspect the 2nd stage Turbine NGVs. 

Table 1: 

GG 1st and/or 2nd Stage Turbine 

Accumulated GG cycles on 05 

January 2011 [Effective Date of 

EASA AD 2010-0273]: 

Compliance time: 

(1st or 2nd Stage Turbine 

Accumulated GG cycles) 

Less than 1 200 (1st and 2nd

Stage Turbine) 

Upon accumulating 1500 total GG 

cycles 

Equal or more than 1 200, and 

less than 1800 (1st or 2nd Stage 

Turbine) 

- Upon accumulating 300 GG cycles 

after 05 January 2011 [Effective 

Date of EASA AD 2010-0273], or

- within 6 months after 05 January 

2011 [Effective Date of EASA AD 

2010-0273], whichever occurs first 

Equal or more than 1 800, and 

less than 2 400 (1st or 2nd Stage 

Turbine) 

- Upon accumulating 200 GG cycles 

after 05 January 2011 [Effective 

Date of EASA AD 2010-0273], or

- within 4 months after 05 January 

2011 [Effective Date of EASA AD 

2010-0273], whichever occurs first

Equal or more than 2 400, and - Upon accumulating 100 GG cycles 
EASA AD No.: 2010-0273R1 

EASA Form 110 Page 3/3

less than 3 000 (1st or 2nd Stage 

Turbine) 

after 05 January 2011 [Effective 

Date of EASA AD 2010-0273], or

- Upon accumulating 3000 GG 

cycles on 1st or 2nd Stage Turbine, or

- within 2 months 05 January 2011 

[Effective Date of EASA AD 2010-

0273], whichever occurs first

More than 3 000 (1st or 2nd Stage 

Turbine) 

Before next flight 

Note 1: The life limit of the “monobloc” Gas Generator 2nd stage turbine 

wheels affected by this AD is 3 000 cycles. 

(5) If during any inspection required by paragraph (4) of this AD, the 2nd

stage Turbine NGVs are found to be not compliant, before next flight, 

replace the affected Module M03 with a serviceable one, in accordance 

with Paragraph 2.B of MSB A292 72 0829 version B. 

(6) After 05 January 2011 [Effective Date of EASA AD 2010-0273], do not 

install a Module 03 with configuration post-TU76 and pre-TU148 M03 

and do not install a Module 03 with configuration post-TU202 and preTU148 M03, unless in compliance with the requirements of this AD. 

(7) Replacement of Module M03 with a serviceable one constitutes a 

terminating action for the requirements of this AD.

Ref. Publications: Turboméca Mandatory Service Bulletin (MSB) A292 72 0829 version B, 

dated 13 December 2010; 

Arriel 1B Maintenance Manual X 292 65 452 1 / X 292 65 452 2 (French 

Version / English Version) 

The use of later approved revisions of these documents 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