EASA AD No: 2010-0147 

EASA Form 110 Page 1/2 

 

EASA AIRWORTHINESS DIRECTIVE 

AD No.: 2011-0147 

Date: 05 August 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 : 

TURBOMECA 

Type/Model designation(s) : 

MAKILA 1 engines 

TCDS Number: EASA.E.072 

Foreign AD: Not applicable 

Supersedure: None 

ATA 77 Engine Indicating – N2 Sensor Harness – Replacement 

Manufacturer(s): TURBOMECA 

Applicability: MAKILA 1A2 engines, all serial numbers. 

These engines are known to be installed in, but not limited to, 

EUROCOPTER AS 332 L2 helicopters. 

Reason: A helicopter experienced an inadvertent activation of the 65% N1 (gas 

generator speed) back up control mode. 

The subsequent technical investigations carried by Turbomeca revealed 

that an N2 (power turbine speed) sensor harness wire crimping 

discrepancy was at the origin of this event. Further quality investigations 

performed with the supplier led to the conclusion that N2 sensor 

harnesses Part Number (P/N) 0 301 52 001 0 whose Serial Numbers 

(S/N) are between S/N 242 and S/N 339 inclusive are potentially 

concerned by the same manufacturing discrepancy. 

This condition, if not corrected, could lead to the inadvertent activation of 

the 65% N1 back up mode and consequently to significant power loss on 

one or both engines installed on the same helicopter, potentially resulting 

in an emergency landing of the helicopter. 

For the reasons described above, this AD requires replacement of 

affected N2 sensor harnesses with serviceable parts. This AD also 

prohibits the installation of non serviceable N2 sensor harnesses on an 

engine. 
EASA AD No: 2010-0147 

EASA Form 110 Page 2/2 

 

Effective Date: 19 August 2011 

Required action(s) 

and Compliance 

Time(s): 

Required as indicated, unless accomplished previously: 

(1) For engines equipped with N2 sensor harnesses P/N 0 301 52 001 0 

whose S/N are between S/N 242 and S/N 339 inclusive, accomplish 

the following actions, in accordance with the instructions of Turbomeca 

Mandatory Service Bulletin 298 77 0817: 

(1.1) Affected P/N is installed on each of the 2 (two) engines of the 

helicopter: within 10 Flight Hours (FH) after the effective date of 

this AD, replace one N2 sensor harness with a serviceable part, 

and within 50 FH after the effective date of this AD, replace the 

second harness with a serviceable part. 

(1.2) Affected P/N is installed only on 1 (one) engine of the helicopter: 

within 50 FH after the effective date of this AD, replace the 

affected N2 sensor harness with a serviceable part.

(2) After modification of an engine as required by paragraph (1) of this AD, 

do not install in an engine an N2 sensor harnesses P/N 0 301 52 001 0 

whose S/N is between S/N 242 and S/N 339 inclusive unless this part 

is serviceable. 

(3) After the effective date of this AD, do not install in a helicopter an 

engine equipped with an N2 sensor harnesses P/N 0 301 52 001 0 

whose S/N is between S/N 242 and S/N 339 inclusive unless this part 

is serviceable. 

Definition: 

For the purpose of this AD, a serviceable N2 sensor harness P/N 0 301 

52 001 0 is: 

• a part not having a S/N between S/N 242 and S/N 339 inclusive; 

• or a part having a S/N between S/N 242 and S/N 339 inclusive 

which has been checked by Turbomeca and on which “SB 0815” 

is marked on the identification plate. 

Ref. Publications: Turbomeca Mandatory Service Bulletin 298 77 0817 Version A. 

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 Safety 

Information Section, Executive Directorate, EASA. E-mail 

ADs@easa.europa.eu. 

4. For any questions concerning the technical content of the 

requirements in this AD, please contact: 

Operator Support & Sales MAKILA 

TURBOMECA 40220 TARNOS – FRANCE 

Phone: +33 (0)5 59 74 40 28 Fax: +33 (0)5 59 74 45 16 or refer to 

your nearest TURBOMECA field representative on 

http://www.turbomeca-support.com.