EASA AD No.: 2009-0035-E

EASA Form 111 Page 1/2 

## EASA EMERGENCY AIRW ORTHINESS DIRECTIVE

AD No.: 2009-0035-E

Date: 18 February 2009

Note: This Emergency 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 t he 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 s hall be ensured by accomplishing 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 Agenc y [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 :

EUROCOPTER Type/Model designation(s) :
EC 155 helicopters

TCDS Number : France No 159

Foreign AD : Not applicable

Supersedure : None



### ATA 34 Navigation – UNS-1D Navigation System – Limitation

Manufacturer(s): EUROCOPTER

Applicability: EUROCOPTER EC 155 B and B1 helicopters, all serial numbers, if equipped with the UNS-1D navigation system.

Reason: During test flights carried out by Eurocopt er, the flight crew noted freezing of the route display on the navigation display (ND) screen in Sector mode. The investigations have revealed that the route display on the ND in Sector mode is no longer refreshed if the flight plan, processed and transmitted by the UNS-1D, contains a procedure that includes a holding pattern or a DME (Distance Measurement Equipment) arc. Only the route display on the ND in Sector mode is affected. The navigation and guidance para meter displays on the ND, the flight plan display on the UNS-1D and the coupli ng to the autopilot are not affected. Freezing of the route display only occurs for flight plans which include procedures in the terminal zone (departure or arrival). If not corrected, freezing of the route di splay during single-pilot operation under IFR conditions would likely result in a signi ficant increase in flight crew workload, possibly causing pilot confusion, affect ing the safety of the helicopter and its occupants. For the reasons described above, this AD prohibits the use of the UNS-1D navigation system for SID and STAR proc edures. The Flight Manual currently prohibits the use of GPS for approach procedures.

Effective Date: 20 February 2009EASA AD No.: 2009-0035-E

EASA Form 111 Page 2/2 Required Action(s) and Compliance Time(s): Required as indicated, unless accomplished previously: (1) Before next flight after the effective date of this AD, amend Flight Manual Supplement 52 to incorporate the following limitation:

" USING FMS FOR SIDS-STARS AND INSTRUMENT APPROACHES IS PROHIBITED " This may be accomplished by inserting a copy of this AD into Flight Manual Supplement 52. (2) Concurrent with the action as required by paragraph (1) of this AD, install a placard on the console, with the same wording as specified in paragraph (1) of this AD, in accordance with the inst ructions of paragraph 2.B of Eurocopter EC155 Alert Service Bulletin (ASB) 04A008.

Ref. Publications: EUROCOPTER EC155 ASB No. 04A008 origi nal issue dated 17 February 2009. 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 subs tantiated, EASA can approve Alternative Methods of Compliance for this AD. 2. The safety assessment has requested not to implement the full consultation process and an immediate pub lication and notification. 3. Enquiries regarding this AD should be referred to the Airworthiness Directives, Safety Management & Research Section, Certific ation Directorate, EASA. E-mail: ADs@easa.europa.eu

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

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