EASA AD No.: 20 1 4

- 0257 R1

TE. CAP.0011 0

- 00 4 © European Aviation Safety Agency. All rights reserved. 1 / 4 Proprietary document. Copies are not controlled. Confirm revision status through the EASA

- Internet/Intranet. 

## EASA AIRWORTHINESS DIRECTIVE

AD No

. : 20 14
- 0257 R1

Date: 29 May 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 accordan ce 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 ope rate 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 : AIRBUS Type/Model designation(s) : A330 and A340 aeroplanes

TCDS Number s : EASA.A.004 and EASA.A.015

F oreign AD: Not applicable

Revision : This AD revises EASA AD 2014

- 0257 dated 27 November 2014.



### ATA 27 Flight Controls

– Trimmable Horizontal Stabilizer Actuator

–

Identification / Replacement

Manufacturer(s): Airbus (formerly Airbus Industrie)
Applicability: Airbus A330

- 201, A330

- 202, A330

- 203, A330

- 223, A330

- 223F, A330

- 243, A330

- 243F, A330

- 301, A330

- 302, A330

- 303, A330

- 321, A330

- 322, A330

- 323, A330

- 341, A330

- 342 and A330

- 343 aeroplanes , all ma nufacturer serial numbers (MSN)

. Airbus A340

- 211, A340

- 21 2, A340

- 213, A340

- 311, A340

- 312 , A340

- 313 , A340

- 541, A340

- 542, A340

- 642 and A340

- 643 aeroplanes , all MSN

. Reason: During endurance qualification tests on Trimmable Horizontal Stabi lizer Actuator (THSA) of another Airbus aeroplane type , a partial loss of the no

- back brake (NBB) efficiency was experienced. Due to THSA design similarity on the A330/A340 fleet , a similar partial loss of the NBB efficiency was identified on THSA P art Nu mber (P/N) 47147 as installed on A330

- 300 and A340

- 200/

- 300 aeroplanes , on THSA P/N 47172 as installed on A330

- 200/

- 300 and A340

- 200/

- 300 aeroplanes , and on THSA P/N 47175 as installed on A340

- 500/600 aeroplanes

. Investigation results concluded that this partial loss of braking efficiency in some specific aerodynamic load conditions was due to polishing and auto

contamination of the NBB carbon friction disks

. This condition, if not detected and corrected and in conjunction with the power gear train not able to keep the ball screw in its last commanded position, could lead to uncommanded movement s of the THS, possibly resulting in loss of control of the aeroplane

.EASA AD No.: 20 1 4

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- Internet/Intranet. To address this potential unsafe condition , EASA issued AD 2013

- 0144 to require replacement of each THSA that ha s exceeded 16 000 f light c ycles ( FC ) in service , to be sent in shop for NBB carbon disk replacement

. Since that AD was issued, a need for clarification has been demonstrated, regarding the identification of the THSA ‘affected’ by this requirement. For this reason, EASA AD 2013

- 0144 was revised, confirm ing that th is AD only affect ed those THSA identified by Part Number (P/N) in Airbus Alert Operator Transmission (AOT) A27L005

- 13. In addition, a note w as added to make clear that the life limits as specified in the current revision of ALS Part 4 are still relevant for the affected THSA, as applicable to aeroplane model and THSA P/N. Since EASA AD 2013

- 0144R1 was issued , f urther assessment of the ageing / endurance issue has resulted in the conclu sion that there is a need to replace the NBB installed on the THSA

. C onsequently , EASA issued AD 2014

- 0257 , which retain ed the requirements of EASA AD 2013

- 0144R1, which was superseded, and require d removal from service of affected THSA. THSA should be sent in shop for NBB carbon disk replacement. This AD affect ed additional THSA P/N when compared to EASA AD 2013

- 0144R1 and Airbus AOT A27L005

- 13. Since that AD was issued, it was determined that it is ne cessary to consider that the THSA removal for NBB disks replacement c ould also be calculated since last NBB disk r eplacement which was done in

- shop

. Effective date: Revision 1: 05 June 2015 Original issue: 11 December 2014
Required A ction(s) and Compliance Time(s) : Required as indicated, unless accomplished previously: Note 1 : The THSA affected by the requirements of this AD are those identified in Table 1 of this AD. Table 1

– Affected THSA P/N Aeroplane THSA P/N
A330 and A340

- 200/

- 300 47147

- 500, 47147

- 700

47172

- 300, 47172

- 500, 47172

- 510, 47172

- 520 A340

- 500/

- 600 47175

- 200, 47175

- 300, 47175

- 500, 47175

- 520 Note 2: For the purpose of this AD, a serviceable THSA is a THSA having a P/N as identified in Table 1 of this AD and which ha s not exceeded the limits identified in this AD , or a THSA with a different P/N , not affected by the requirements of this AD. Note 3: The THSA life limits as specified in the current revision of ALS Part 4 are still relevant, as applicable to aeroplane model and THSA P/N

. Note 4: A review of the aeroplane delivery or maintenance records is acceptable for the P/N determination in lieu of the inspection as specified in the applicable Airbus SB, provided that the aeroplane configuration and installed components can be conclusively determined from that review.
Part A
- For A330 and A340
- 200/
- 300 aeroplanes ( 1 ) W ithin the compliance time as specified in T able 2 of this AD , depending on the FC accumulated by the THSA on 31 July 2013 [the effective date of EASA AD 2013

- 0144 at original issue] , but not later than the thresholds specified in Table 3 of this AD, depending on the FC accumulated by the THSA on each corresponding date specified in Table 3 of this AD, replace each affected THSA with a serviceable unit in accordance with the instructions of Airbus SB A330

- 27

- 3199 or SBA340

- 27

- 4190 as applicable to aeroplane type and model

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- Internet/Intranet. Table 2
FC accumulated by the THSA on 31 July 2013 ( the effective date of the original issue of EASA AD 2013

- 0144 ) since first installation on an aeroplane , or sinc e last NB B replacement, whichever is later Compliance T ime

20 000 FC or more within 1 500 FC after 31 July 2013

16 000 FC or more, but less than 20 000 FC A330: within 4 000 FC after 31 July 2013 A340: within 3 000 FC after 31 July 2013
Less than 16 000 FC a s specified in paragraph ( 2 ) of this AD

(2) Not later than the date specified in Table 3 of this AD, as applicable, for THSA having reached or exceeded on that date the corresponding number of FC as specified in Table 3 of this AD , replace the THSA with a serviceable unit in accordance with the instructions of Airbus SB A330

- 27

- 3199 , or SB A340

- 27

- 4190 , as applicable to aeroplane type and model. Table 3

– THSA Removal for NBB Disks Replacement

D ate THSA FC Limit ( since first installation on

an aeroplane , or since last NB B replacement, whichever is lat e r ) 31 July 2014 20 000 FC 31 J an u ar y 201 6 16 000 FC 31 July 2017 14 000 FC 31 July 2018 12 000 FC

Part B

– For A340
- 500/
- 600 aeroplanes ( 3 ) Not later than the date specified in Table 4 of this AD, as applicable, for THSA having reached or exceeded on that date the corresponding number of FC specified in Table 4 of this AD , replace the THSA with a serviceable unit in accordance with the instruc tions of Airbus SB A340

- 27

- 5062

.

Table 4

– THSA Removal for NBB Disks Replacement

Date THSA FC Limit (since first installation on

an aeroplane , or since last NB B replacement, whichever is lat e r ) 31 October 2015 6 000 FC 3 0 April 2017 5 200 FC 30 April 2018 4 400 FC 30 April 2019 3 500 FCEASA AD No.: 20 1 4

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- Internet/Intranet. Part C

– For all aeroplanes affected by this AD ( 4 ) From the date as specified in Table 3 or Table 4 of this AD, as applicable to aeroplane type and model , and before exceeding the FC limit corresponding to each date, as applicable, replace each affected THSA with a serviceable unit (see also paragraph (5) of this AD) in accordance with the instructions of Airbus SB A330

- 27

- 3199 , or SB A340

- 27

- 4190 , or SB A340

- 27

- 5062 , as applicable to aeroplane type and model

. Conditions for the installation of an affected THSA on an aeroplane : ( 5 ) From each date specified in Table 3 or Table 4 of this AD, as applicable, it is allowed to install a THSA on an aeroplane , provided the unit has not exceeded the corresponding number of FC specified in Table 3 or Table 4 of this AD , as applicable to aeroplane type/model

. Ref. Public ations: Airbus SB A330

- 27

- 3199 dated 15 July 2014

. Airbus SB A340

- 27

- 4190 dated 15 July 2014

. Airbus SB A340

- 27

- 5062 dated 15 July 2014. T he u se of later approved revisions of th ese document s 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 original issue of t his AD was posted on 25 July 2014 as PAD 14

- 121 and republished as PAD 14

- 121R1 on 06 November 2014 for consultation until 20 November 2014 . The Comment Response Document can be found at http://ad.easa.europa.eu/

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

– EIAL; E

- mail: airworthiness.A330

- A340@airbus.com

.