EASA AD No : 2011-0108 

EASA Form 110 Page 1/3 

EASA AIRWORTHINESS DIRECTIVE 

AD No.: 2011-0108 

Date: 07 June 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: 

EUROCOPTER 

Type/Model designation(s): 

EC 155 helicopters 

TCDS Number: France No. 159 

Foreign AD: Not Applicable 

Supersedure: This AD supersedes EASA AD 2007-0259R1 dated 28 September 2007, including the 

Correction dated 26 February 2010. 

ATA 53 Fuselage – Upper Fin / Fenestron Attachment Fittings – Inspection / 

Replacement 

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

Applicability: EC 155 B and EC 155 B1 helicopters, all serial numbers. 

Reason: In 2007, an in-flight event with an EC 155 B1 helicopter was reported, resulting in 

the loss of the fin. During the investigation, a crack in the fittings attaching the 

upper fin to the fenestron (tail rotor assembly) was discovered. Analysis has 

shown that such type of crack is likely to exist or develop in other helicopters with 

the same fin / fenestron design: EC 155 B, SA 365 and AS 365 series, and SA 

366 G1 helicopters. 

This condition, if not detected and corrected, could lead to detachment of the fin 

during flight, possibly resulting in reduced control of the helicopter and/or injury to 

persons on the ground. 

Prompted by this event and pending the results of the investigation, EASA issued 

Emergency AD 2007-0259-E to require repetitive inspections of the upper fin 

attachment fittings. 

The results of subsequent investigations have shown that, due to lower loads 

compared to those which applies on the EC 155 fin / fenestron fittings, the unsafe 

condition cannot exist on SA 365, AS 365 and SA 366 helicopters and EASA AD 

2007-0259-E was revised to delete those helicopters from the AD applicability. 

Eurocopter have now developed modification (MOD) 0754B40 to increase the 

strength of the fuselage-fin junction fittings which constitutes terminating action 

for the repetitive inspections. MOD 0754B40 encompasses the replacement of 

the two-piece fin fittings, front fittings Part Number (P/N) 365A23-4240-01 and 
EASA AD No : 2011-0108 

EASA Form 110 Page 2/3 

P/N 365A23-4242-01 and rear fittings P/N 365A23-4241-01 and P/N 

365A23-4243-01, by two reinforced single-piece fittings, front fitting P/N 

365A23-4218-20 and rear fitting P/N 365A23-4219-20. 

For the reasons described above, this AD retains parts of the requirements of 

EASA AD 2007-0259R1, which is superseded, and requires the implementation 

of the MOD 0754B40. 

Effective Date: 21 June 2011 

Required Action(s) 

and Compliance 

Time(s): 

Required as indicated, unless accomplished previously: 

(1) Within 15 flight hours (FH) after 02 October 2007 [the effective date of EASA 

AD 2007-0259-E], or within 55 FH since the helicopter first flight, whichever 

occurs later, inspect the front and rear upper fittings, P/N 365A23-4242-01 

and P/N 365A23-4243-01 respectively, and the front and rear lower fittings, 

P/N 365A23-4240-01 and P/N 365A23-4241-01 respectively, of the upper fin 

in accordance with the instructions of Eurocopter EC155 Alert Service 

Bulletin (ASB) 05A017 revision 2. 

(2) Thereafter, at intervals not to exceed 55 FH, repeat the inspection required 

by paragraph (1) of this AD in accordance with the instructions of Eurocopter 

EC155 ASB 05A017 revision 2. 

(3) If, during the inspections required by paragraphs (1) and (2) of this AD, any 

crack is found, before next flight, replace the shroud/fin junction fittings in 

accordance with the instructions of Eurocopter EC155 SB 53-029 Revision 1 

(implementation of MOD 0754B40). 

(4) Inspections of attachment fittings, accomplished before the effective date of 

this AD, in accordance with the instructions of Eurocopter EC155 ASB 

05A017 at original issue and revision 1, are considered acceptable for 

compliance with the inspection requirements of this AD. 

(5) Within 6 calendar months after the effective date of this AD, unless already 

accomplished as required by paragraph (3) of this AD, replace the shroud/fin 

junction fittings in accordance with the instructions of Eurocopter EC155 SB 

53-029 Revision 1 (implementation of MOD 0754B40). 

(6) Modification of a helicopter, as required by paragraph (3) or (5) of this AD, as 

applicable, constitutes terminating action for the repetitive inspection 

requirements of this AD for that helicopter. 

(7) After modification of a helicopter, as required by paragraph (3) or (5) of this 

AD, or after in-production embodiment of MOD 0754B40, do not install upper 

fin attachment front fittings P/N 365A23-4240-01 and 365A23-4242-01 or rear 

fittings P/N 365A23-4241-01 and P/N 365A23-4243-01 on any helicopter. 

Ref. Publications: Eurocopter EC155 Alert Service Bulletin 05A017 Revision 2 dated 09 December 

2010. 

Eurocopter EC155 Service Bulletin 53-029 Revision 1 dated 10 March 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. This AD was posted on 02 May 2011 as PAD 11-046 for consultation until 30 

May 2011. No comments were received during the consultation period. 

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. 
EASA AD No : 2011-0108 

EASA Form 110 Page 3/3 

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 (0) 4 42 85 97 97, Fax +33 (0) 4 42 85 99 66 

E-mail: Directive.technical-support@eurocopter.com.