EASA AD No.: 2013

- 0133

TE. CAP.00110

- 00 3 © European Aviation Safety Agency. All rights reserved. 1 / 2 Proprietary document. Copies are not controlled. Confirm revision status through the EASA

- Internet/Intranet. 

## EASA AIRWORTHINESS DIRECTIVE

AD No

. : 2013

- 0133

Date: 28 June 2013

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 E U 748/2012 , Part 21A.3B. In accordance with E C 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 ope rate 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].



### Design Approval Holder’s Name :
EUROCOPTER Type/Model designation(s) :
AS 350 and AS 355 helicopters

TCDS Number: EASA.R.008, EASA.R.146

F oreign AD: Not Applicable

Supersedure: None



### ATA 64 Tail Rotor

– Tail Rotor Hub P itch H orn

– Inspection / Replacement

Manufacturer(s): Eurocopter (formerly Eurocopter France, Aerospatiale)

Applicability: AS 350 B, AS 350 BA, AS 350 BB, AS 350 B1, AS 350 B2, AS 350 B3

, AS 350 D

, AS 355 E, AS 355 F, AS 355 F1, AS 355 F2, AS 355 N and AS 355 NP helicopters, all s erial n umbers , equipped with T ail R otor Hub (TRH) pitch horn assemblie s (hereafter called ‘assembly’) P art N umber (P/N) 350A121368.01 , P / N 350A121368 .02

, P / N 350A121368 .03

, or P / N 350A121368

. 04

, incorporating TRH pitch horn ( hereafter called ‘ part ’ ) P/N 350A121368.XX (where XX stands for two digit dash number excluding 01, 02, 03, and 04 which are reserved for assemblies ).

Note: Either the assembly P/N or the part P/N can be marked on the affected TRH pitch horns.

Reason: Eurocopter ha v e been informed of a case of crack detection o n the yoke of a TRH pitch horn. The investigation of this occurrence is on

- going and the cause has not yet been determined.

This condition, if not detected and corrected , may eventually lead to the failure of the two horn yokes, resul ting in the loss of the anti

- torque function, possibly resulting in loss of control of the helicopter.

To address this condition, Eurocopter issued Emergency Alert Service Bulletin (ASB) No. 05.00.74 for AS 350 helicopters and ASB No. 05.00.65 for AS 355 helicopters. Shortly t hereafter, t hese ASBs hav e been updated and reissued by Eurocopter at R ev ision 1 to clarify that the affected TRH pitch horns can beEASA AD No.: 2013

- 0133

TE. CAP.00110

- 00 3 © European Aviation Safety Agency. All rights reserved. 2 / 2 Proprietary document. Copies are not controlled. Confirm revision status through the EASA

- Internet/Intranet. identified by means of either assembly P/N ’ s or part P/N ’ s marked thereon and
to implement a documentary change to some of tail rotor blade assembly log cards.
For the reasons described above, this AD requires repetitive visual inspections of the affected TRH pitch horns to detect cracks and, depending on findings, replacement with a serviceable assembly

. This AD is considered an interim action and further AD action may follow.

Effective Date: 03 July 2013

Required A ction(s) and Compliance Time(s) : Required as indicated, unless accomplished previously:
(1) I nitially

, w ithin the compliance time indicated in Table 1 of this AD and

, thereafter

, at intervals not to exceed 165 flight hours (FH)

, visually inspect both TRH pitch horn s in accordance with the instructions of paragraph 3.B.2.a. of AS350 ASB No. 05.00.74 or AS355 ASB No. 05.00.65, as appli cable to helicopter type.

Table 1

– Initial inspection

FH accumulated by the TRH pitch horn on the effective date of this AD Compliance Time

More than 155 FH since new Within 10 FH after the effective date of this AD

Less than or equal to 155 FH since new Before exceeding 165 FH since new

(2 ) If, during any inspection as required by paragraph (1) of this AD

, any crack is found, before next flight, replace the affected assembly in accordance with the instructions of paragraph 3.B.2.b. of AS350 ASB No. 05.00 .74 or AS355 ASB No. 05.00.65, as applicable to helicopter type.
(3) Replacement of a TRH pitch horn with a serviceable assembly as required by paragraph (2) of this AD does not constitute terminating action for the repetitive inspections required by paragraph (1) of this AD.

Ref. Public ations: Eurocopter AS350 ASB No. 05.00.74 original issue dated 27 May 2013

, or R ev. 1 dated 2 5 June 2013.
Eurocopter AS355 ASB No. 05.00.65 original issue dated 27 May 2013

, or R ev. 1 dated 2 5 June 2013.

The u se 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. Based on t he required actions and the compliance time, EASA have decided to issue a Final AD with Request for Comments

, postponing the public consultation process until after publication

. 3. Enquiries regarding t his A D 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: EUROCOPTER (STDI)

– Aéroport de Marseille Provence 13725 Marignane Cedex, France, Telephone +33 (4) 42 85 97 97, Facsimile +33 (4) 42 85 99 66, E

- mail: Directive.technical

- support@eurocopter.com

.