EASA AD No.: 2011-0033

EASA Form 110 Page 1/2 

## EASA AIRWORTHINESS DIRECTIVE

AD No.: 2011-0033

Date: 01 March 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 participat e 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 a ccomplishing any applicable ADs. Consequently, no person may opera te an aircraft to which an AD applies, except in accordance with the requirements of that AD unless otherwise specified by the Age ncy [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) exemptio n]. 

### Type Approval Holder’s Name :
EUROCOPTER Type/Model designation(s) :
AS350 Helicopters

TCDS Number : EASA R.008

Foreign AD : Not applicable

Supersedure : None



### ATA 29 Hydraulic Power – Forward Hydraulic Servo Control Hoses / Protection Installation

Manufacturer(s): Eurocopter (formerl y Eurocopter France, Aerospatiale)
Applicability: AS 350 B, BA, BB, D, B1, B2, and B3 helicopters, all serial numbers, with a single hydraulic power system and the fo llowing forward (pitch) servo-control hydraulic hoses installed: - P/N 704A34-412-033 (other reference MP/N 675-102-05-01); - P/N 704A34-412-035 (other reference MP/N 675-102-06-01).
Reason: An in-flight fire in the main gearbox compartment occurred on an AS350B2 helicopter. The fire was caused by ignition of hydraulic fluid leaking from a hydraulic hose, which had been damaged following an electrical fault in a circuit located in the compartment that is not fire protected. An in-flight fire in the main gearbox compartment during a continued flight, when undetected or if a landing could not be performed immediately, can result in loss of hydraulics, possible shut down of the engine because of fire effects and damage to the Main Rotor (MR) control system. This condition, if not prevented, could lead to loss of MR control, potential power loss, structural damage and propagation of fire into the cabin or other compartments, consequently with loss of control of the helicopter and possible injury of the occupants. For the reasons described above, this AD requires installation of protection sleeves on hydraulic hoses as a final solution.

Effective Date: 15 March 2011EASA AD No.: 2011-0033

EASA Form 110 Page 2/2 Required Action(s) and Compliance Time(s): Required as indicated, unless accomplished previously: (1) Within 30 days after the effective date of this AD install protection sleeves P/N 706A34-402-225 and 706A34-402- 224 on hydraulic hoses P/N 704A34-412-033 and 704A34-412-035 respecti vely in accordance with the instructions of paragraph 2.B.2 of the Alert Service Bulletin (ASB) No. 29.00.13. (2) Helicopters equipped in production with modification 074238 are in compliance with the requirements of paragraph (1) of this AD. (3) After the effective date of this AD, do not install on any helicopter hydraulic hoses P/N 704A34-412-033 and 704A 34-412-035 without protection sleeves P/N 706A34-402-225 and 706A34-402-224 respectively.

Ref. Publications: EUROCOPTER AS350 B, BA, BB, D, B1, B2, B3 ASB No. 29.00.13 Revision 0, dated 26 July 2010 or later approved revisions.

Remarks : 1. If requested and appro priately substantiated, EASA can accept Alternative Methods of Compliance for this AD. 2. The required actions and the risk a llowance 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 & Re search Section, Certification Directorate, EASA. E-mail ADs@easa.europa.eu

. 4. For any question concerning the tec hnical content of the requirements in this AD, please contac t: EUROCOPTER (STDI) - Aéroport de Marseille Provence 13725 Marignane Cedex - France. Tel: +33 (0) 4 42 85 97 97 - Fax: +33 (0) 4 42 85 99 66. E-mail: Directive.technical-support@eurocopter.com