EASA AD No.: 2015-0162

TE.CAP.00110-004 © European Aviation Safety Agency. All rights reserved. 1/3

Proprietary document. Copies are not controlled. Confirm revision status through the EASA-Internet/Intranet.

EASA AIRWORTHINESS DIRECTIVE

AD No.: 2015-0162

Date: 06 August 2015

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 EU 748/2012, Part 21.A.3B. In accordance with EU 1321/2014 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 [EU 

1321/2014 Annex I, Part M.A.303] or agreed with the Authority of the State of Registry [EC 216/2008, Article 14(4) exemption].

Design Approval Holder’s Name:

TURBOMECA

Type/Model designation(s):

ARRIEL 2 engines

TCDS Number: EASA.E.001

Foreign AD: Not applicable

Supersedure: None

ATA 72

Engine – Accessory Gear Box Module M01 – Inspection / 

Replacement

Manufacturer(s): Turboméca

Applicability: ARRIEL 2B, 2B1, 2B1A, 2B1B, 2C, 2C1, 2C2, 2D, 2E, 2N, 2S1 and 2S2 

engines, all serial numbers.

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

Helicopters AS350B3, EC130B4, EC130T2, AS365N3, EC155B and EC155B1, 

Airbus Helicopters Deutschland MBB-BK 117 D-2 (EC145T2 or H145), Avic 

international AC311 and Sikorsky S-76C helicopters.

Reason: An uncommanded in-flight shut-down (IFSD) of an ARRIEL 2 engine was 

reported, caused by rupture of the 41-tooth gear, which forms part of the bevel 

gear of the accessory gearbox (module M01). The subsequent investigation 

revealed that wear on the housing of the front bearing of this gear was a major 

contributor to this rupture. In addition, the investigation showed that this wear 

mechanism had resulted in positive Spectrometric Oil Analysis (SOA)

indications before the event.

This condition, if not detected and corrected, could potentially lead to further 

cases of IFSD, possibly resulting in an emergency landing.

To address this potentially unsafe condition, Turboméca issued Mandatory 

Service Bulletin (MSB) 292 72 2861 to provide SOA check instructions.

For the reasons described above, this AD requires repetitive SOA checks and, 

depending on the results, replacement of the module M01. 
EASA AD No.: 2015-0162

TE.CAP.00110-004 © European Aviation Safety Agency. All rights reserved. 2/3

Proprietary document. Copies are not controlled. Confirm revision status through the EASA-Internet/Intranet.

Effective Date: 20 August 2015

Required Action(s) 

and Compliance

Time(s):

Required as indicated, unless accomplished previously:

(1) Within the compliance time specified in Table 1 of this AD, perform a visual 

inspection in accordance with the instructions of Turboméca MSB 

292 72 2861 to identify, if a machined front casing Part Number (P/N)

0292120650 is installed on that engine.

(2) For engines equipped with a module M01 fitted with a machined front 

casing P/N 0292120650 (as identified in Turboméca MSB 292 72 2861), 

within the compliance time specified in Table 1 of this AD, and, thereafter, 

at intervals not to exceed 100 EH, unless otherwise required by paragraph 

(3) and (4) of this AD, accomplish a SOA check in accordance with the 

instructions of Turboméca MSB 292 72 2861.

Table 1 – Initial SOA check

Engine Hours (EH) accumulated by 

the Module M01 (since first installation 

on an engine or since last overhaul)

Compliance Time

Less than 800 EH Before exceeding 850 EH

since first installation of the 

Module M01 on an engine, or 

since last Module M01 

overhaul, as applicable

800 EH or more, or EH not known Within 50 EH after the 

effective date of this AD

(3) If, during any SOA check as required by paragraph (2) of this AD, an 

aluminium concentration has value between 0.8 ppm and 1.4 ppm 

(inclusive), accomplish further SOA checks at intervals not to exceed 50 

EH to comply with paragraph (2) of this AD.

(4) If, during any SOA check, as required by paragraph (2) or (3) of this AD, 

the aluminium concentration is above 1.4 ppm, within 50 EH after that SOA 

check, replace the module M01 with a serviceable module M01 (refer to 

paragraph (5) of this AD), in accordance with the instructions of 

Turboméca MSB 292 72 2861.

(5) For the purpose of this AD, a serviceable module M01 is either a module 

M01 fitted with a machined front casing P/N 0292120650, that is subjected 

to SOA checks in accordance with paragraph (2) and (3) of this AD, or a 

module M01 fitted with a casted front casing P/N 0292127020

(6) From the effective date of this AD, it is allowed to install a module M01 

fitted with a machined front casing P/N 0292120650, provided it is 

subjected to SOA checks in accordance with paragraph (2) and (3) of this 

AD.

Ref. Publications: Turboméca MSB 292 72 2861 version A dated 24 April 2015.

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 23 June 2015 as PAD 15-079 for consultation until 

21 July 2015. No comments were received during the consultation period.

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

Section, Certification Directorate, EASA. E-mail: ADs@easa.europa.eu.
EASA AD No.: 2015-0162

TE.CAP.00110-004 © European Aviation Safety Agency. All rights reserved. 3/3

Proprietary document. Copies are not controlled. Confirm revision status through the EASA-Internet/Intranet.

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 TURBOMECA technical 

representative (refer to http://www.turbomeca-support.com).