EASA AD No.: 2011-0073 

EASA Form 110 Page 1/3 

EASA AIRWORTHINESS DIRECTIVE 

AD No.: 2011-0073 

Date: 20 April 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 : 

AIRBUS

Type/Model designation(s) : 

A330 and A340 aeroplanes 

TCDS Number : EASA.A.004, EASA.A.015 

Foreign AD : Not applicable 

Supersedure : None 

ATA 26 Fire protection – Fire Detection Unit (FDU) – Inspection / 

Replacement 

Manufacturer(s): Airbus (formerly Airbus Industrie) 

Applicability: Airbus A330 aeroplanes, models -201, -202, -203, -223, -223F, -243, -243F, 

-301, -302, -303, -321, -322, -323, -341, -342 and -343, all manufacturer serial 

numbers (MSN). 

Airbus A340 aeroplanes, models -211, -212, -213, -311, -312, -313, -541, 

-542, -642 and -643, all MSN. 

Reason: During a pre-flight test before delivery of an aeroplane from the Airbus 

production line, a fault message was triggered on FDU1. 

Investigations by the supplier on the faulty FDU have identified a soldering 

quality issue on one of the internal cards. This quality issue resulted from a 

specific repair process that was applied to some FDU Part Number (P/N) 

3711-00 during manufacturing. 

The FDU monitors the engine, Auxiliary Power Unit (APU) and Main Landing 

Gear (MLG) bay fire detection systems. 

This condition, if not corrected, may adversely affect the fire detection system 

performance in case of a fire in the area that is monitored by the faulty FDU, 

potentially resulting in an unsafe condition. 

For the reasons described above, this AD requires the identification and 

replacement of the affected FDU. 

Effective Date: 04 May 2011 
EASA AD No.: 2011-0073 

EASA Form 110 Page 2/3 

Required Action(s) 

and Compliance 

Time(s): 

Required as indicated, unless accomplished previously: 

(1) Within 1 000 Flight Hours (FH) after the effective date of this AD, 

accomplish the actions of paragraphs (1.1) and (1.2) of this AD: 

(1.1) Inspect the Fire Detection Unit (FDU) of each engine, of the APU 

and, if applicable, of the MLG Bay (A340-500/-600 aeroplanes 

only) to identify the P/N and serial number (s/n), in accordance 

with the instructions of Airbus All Operators Telex (AOT) 

A330-26A3052, or AOT A340-26A4044, or AOT A340-26A5024, 

as applicable to aeroplane type and model. 

(1.2) If a P/N 3711-00 FDU is installed and the s/n of the FDU, identified 

as required by paragraph (1.1) of this AD, is listed in Table 1 of 

this AD, replace the affected FDU with a serviceable FDU, in 

accordance with the instructions of Airbus AOT A330-26A3052 or 

AOT A340-26A4044 or AOT A340-26A5024, as applicable to 

aeroplane type and model. 

Table 1 – Affected P/N 3711-00 Fire Detection Units 

s/n 

ZL0683 

ZL0718 

ZL0721 through ZL0725 inclusive 

ZL0727 

ZL0729 through ZL0731 inclusive 

ZL0736 

ZL0738 

ZL0740 

ZL0742 and ZL0743 

ZL0745 

ZL0747 

ZL0770 

ZL0772 

ZL0775 

ZL0788 

ZL0804 

Note: For information, some of the affected P/N 3711-00 FDU have been 

installed in production on certain aeroplanes, as indicated in Table 2 below: 

Table 2 – FDU Installed in production 

A330, MSN Position s/n 

1177 ENG2 FDU (1WD2) ZL0683 

1191 ENG2 FDU (1WD2) ZL0723 

ENG1 FDU (1WD1) ZL0721 1192 

ENG2 FDU (1WD2) ZL0722 

1193 APU FDU (13WG) ZL0718 

1195 ENG1 FDU (1WD1) ZL0740 

ENG1 FDU (1WD1) ZL0742 

1196 ENG2 FDU (1WD2) ZL0736 

APU FDU (13WG) ZL0743 

1198 ENG2 FDU (1WD2) ZL0738 

1199 APU FDU (13WG) ZL0731 

1200 ENG1 FDU (1WD1) ZL0747 

1206 ENG2 FDU (1WD2) ZL0770 

(2) A review of the aeroplane maintenance records is acceptable in lieu of 

the inspection required by paragraph (1.1) of this AD, provided the P/N 

and s/n of the installed FDU can be conclusively identified from that 

review. 
EASA AD No.: 2011-0073 

EASA Form 110 Page 3/3 

(3) From the effective date of this AD, do not install on an aeroplane any P/N 

3711-00 FDU with a s/n listed in Table 1 of this AD, unless the FDU has 

been repaired in accordance with the instructions of Airbus AOT 

A330-26A3052, or AOT A340-26A4044, or AOT A340-26A5024, as 

applicable to aeroplane type and model. 

Ref. Publications: Airbus All Operators Telex A330-26A3052 dated 19 April 2011; 

Airbus All Operators Telex A340-26A4044 dated 19 April 2011; 

Airbus All Operators Telex A340-26A5024 dated 19 April 2011. 

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: AIRBUS – Airworthiness Office – EAL; 

E-mail: airworthiness.A330-A340@airbus.com .