EASA AD No.: 2011-0218 

EASA Form 110 Page 1/2

EASA AIRWORTHINESS DIRECTIVE 

AD No.: 2011-0218 

Date: 10 November 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 2 series engines 

TCDS Number : EASA.E.001 

Foreign AD : Not applicable 

Supersedure : None 

ATA 72 Engine – Module M04 (Power Turbine) / Power Turbine Blades 

– Life Limit / Replacement 

Manufacturer(s): Turboméca S.A. 

Applicability: Arriel 2B, 2B1, 2B1A, 2B1B engines, all serial numbers. 

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

AS 350 B3, EC 130 B4, AS 350 C3 helicopters and Changue Z11 

helicopters. 

Reason: During production of Arriel 2 Power Turbine (PT) wheels, Turboméca have 

detected geometric non-conformities on blade fir-tree roots. The technical 

investigations carried out by Turboméca have shown that this nonconformity is due to PT blade manufacturing and that only a limited 

number of PT blades are potentially affected. 

This situation, if not detected and corrected, may potentially lead to a 

reduction in the fatigue resistance of the PT blades, which can reduce 

their in service use limit. This reduction of fatigue resistance can 

potentially result in blade rupture, which could cause an uncommanded inflight shut down, ultimately leading to an emergency autorotation landing 

for a single-engine helicopter. 

To address this unsafe condition, Turboméca have issued Turboméca 

Mandatory Service Bulletin (MSB) A292 72 2842 version A, in which the 

life limit of those PT blades is reduced to 5 000 Flight Cycles (FC). 

For the reasons stated above, this AD requires an identification of the 

installed PT blades, replacement of the affected blades before or upon 
EASA AD No.: 2011-0218 

EASA Form 110 Page 2/2

accumulation of the new life limit. It prohibits as well installation of an 

affected PT blade on an installed engine or an engine to be installed, 

unless the PT blade is in compliance with the requirements of this AD. 

Effective Date: 24 November 2011 

Required Action(s) 

and Compliance 

Time(s): 

Required as indicated, unless accomplished previously: 

(1) Within one month after the effective date of this AD, identify if the M04 

Power turbine wheel assembly has at least one installed PT blade 

having: 

• a Part Number (P/N) 2 292 81 A01 0, and 

• Serial Numbers (S/N) 102782 through 120230 inclusive or S/N 

120293 through 120390 inclusive. 

Note: The instructions for the identification of the serial number of the PT 

blades of the module M04 are given in paragraph 2B(1)(a) of Turboméca 

MSB A292 72 2842 version A. 

(2) If an affected PT blade is installed, concurrent to the identification as 

required by paragraph (1) of this AD, record the life limit of 5 000 FC 

for that PT blade in the module M04 log book and the engine log 

book, in accordance with the instructions of paragraph 2.B.(1)(b) of 

Turboméca MSB A292 72 2842 version A, and, upon or before 

accumulation of 5 000 FC by a PT blade since first installation on an 

engine, accomplish one of the following actions, in accordance with 

paragraphs 2.B.(1)(b) and 2.B.(2) of Turboméca MSB A292 72 2842 

version A: 

• Replace the PT blade with a serviceable PT blade; 

• Replace the module M04 with a module M04 embodying serviceable 

PT blades; 

• Replace the PT wheel assembly with a PT wheel assembly 

embodying serviceable PT blades. 

(3) From the effective date of this AD, do not install a PT blade as listed in 

paragraph (1) of this AD on an installed engine or an engine to be 

installed on a helicopter, unless the PT blade is in compliance with the 

requirements of this AD. 

Ref. Publications: Turboméca Mandatory Service Bulletin A292 72 2842 version A, dated 23 

September 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. This AD was posted on 10 October 2011 as PAD 11-107 for 

consultation until 07 November 2011. The Comment Response 

Document can be found at http://ad.easa.europa.eu. 

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

Information Section, Executive 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 2 Customer Support 

40220 Tarnos, France 

Fax: +33 5 59 74 45 15 or your usual or nearest Turboméca technical 

representative at www.turbomeca-support.com.