EASA AD No : 2009-0171 

EASA Form 110 Page 1/3 

EASA AIRWORTHINESS DIRECTIVE 

AD No.: 2009-0171 

Date: 05 August 2009 

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 : 

AIRBUS 

Type/Model designation(s) : 

A300, A310, A300-600 and 

A300-600ST aeroplanes 

TCDS Number : France No. 145 and EASA.A.014 

Foreign AD : Not applicable 

Supersedure : None 

ATA 26, 29 Fire Protection / Hydraulic Power - Air Pressurisation Check Valves 

– Identification / Replacement 

Manufacturer(s): AIRBUS (formerly AIRBUS INDUSTRIE). 

Applicability: 

AIRBUS A300, A310 and A300-600 aeroplanes, all certified models, all serial 

numbers, and AIRBUS A300F4-608ST aeroplanes, all serial numbers, if Crissair 

check valves P/N 2S2794-1 are installed. 

Reason: 

In the past, some operators have reported difficulties to pressurise the 

hydraulic reservoirs, due to leakage of the Crissair reservoir air pressurisation 

check valves. In some cases, the air conditioning system was contaminated 

with hydraulic mist. The leakage of the check valves was caused by an 

incorrect spring material. The affected Crissair check valves Part Number 

(P/N) 2S2794 were then replaced with improved check valves P/N 2S2794-1 

in accordance with Airbus Service Information Letter 29-020. 

More recently, similar issues were again reported on aeroplanes with Crissair 

check valves P/N 2S2794-1 installed. The investigations carried out on those 

check valves have shown that a spring, mounted inside the valve, does not 

meet the Airbus type design specifications. 

This situation, if not corrected, can cause hydraulic system functional 

degradation, possibly resulting in reduced control of the aeroplane when 

combined with an air duct leak, air conditioning system contamination or, if 

installed, malfunction of the fire extinguishing system in the Class ‘C’ cargo 

compartment. 

For the reasons described above, EASA AD 2008-0166 was issued to require 

the inspection of the Crissair check valves P/N 2S2794-1, to identify serial 
EASA AD No : 2009-0171 

EASA Form 110 Page 2/3 

numbers (s/n) and the replacement of the affected ones with serviceable units. 

Later on, further investigation by the vendor Crissair revealed more suspect 

check valves P/N 2S2794-1. Based on this, it was concluded that EASA AD 

2008-0166 did not adequately address the unsafe condition and also did not 

correctly identify the Functional Item Numbers (FIN) of the various aeroplane 

installations of the affected valves. Consequently, EASA AD Cancellation Notice 

No.: 2008-0166-CN was issued on 29 October 2008 to cancel EASA AD 2008-

0166. 

An updated list of suspect check valves with P/N 2S2794-1 has now been issued 

by Crissair Inc., the manufacturer. Consequently, this EASA AD requires the 

identification of the check valves by s/n and the replacement of the affected ones 

with serviceable units. 

Effective Date: 19 August 2009 

Required Action(s) 

and Compliance 

Time(s): 

Required as indicated, unless accomplished previously: 

(1) Within the time period indicated in Table 1 of this AD, identify the Serial 

Number (S/N) of Crissair check valves P/N 2S2794-1, using Appendix 1 

(complete list for aeroplanes not already compliant with EASA AD 2008-

0166 requirements) or Appendix 2 (additional list for aeroplanes already 

compliant with EASA AD 2008-0166 requirements) of Airbus Service 

Bulletin (SB) A300-29-0124 Revision 02, SB A310-29-2097 Revision 01, 

SB A300-29-6060 Revision 01 or SB A300-29-9009 Revision 02, as 

applicable to aeroplane model. Depending on findings, apply corrective 

action(s) in accordance with the instructions of Airbus SB A300-29-0124 

Revision 02, SB A310-29-2097 Revision 01, SB A300-29-6060 Revision 

01 or SB A300-29-9009 Revision 02, as applicable to aeroplane model. 

Note: Check Valves P/N 2S2794-1 marked with "R" have already been 

modified per Vendor Service Bulletin No. 20070407-29-1 and therefore do 

not need to be replaced. Check valves P/N 2S2794 are not affected. 

- Table 1 - 

Affected check valve installation, 

identified by FIN (Functional Item 

Number): 

Compliance time: 

Hydraulic System (all aeroplanes) - 

FIN 29/1388, FIN 29/2388 and FIN 29/3388 

Cargo Compartment Fire Extinguishing 

System, equipped with Flow Metering 

System (A310 and A300-600 aeroplanes 

“post Airbus modification 06403” only) - FIN 

26/0203 

Within 4 months after the 

effective date of this AD 

Hydraulic System (all aeroplanes) - 

FIN 29/1378, FIN 29/1382 and FIN 29/1394 

Hydraulic System (A300 aeroplane 

Configuration 01 “pre Airbus modification 

03079” only) - FIN 29/1381 

Within 30 months after the 

effective date of this AD 

 

(2) After replacement of all affected check valves on an aeroplane, as 

required by paragraph (1) of this AD, do not install any Crissair P/N 

2S2794-1 check valve on that aeroplane, unless it has a serial number 

other than those listed in AIRBUS SB A300-29-0124 Revision 02, A310-

29-2097 Revision 01, A300-29-6060 Revision 01 or A300-29-9009 

Revision 02, or unless check valve P/N 2S2794-1 is marked with ‘R’. 
EASA AD No : 2009-0171 

EASA Form 110 Page 3/3 

(3) Within 3 weeks after the inspection, fill in the inspection reporting sheet in 

accordance with the instructions of AIRBUS SB A300-29-0124 Revision 

02, A310-29-2097 Revision 01, A300-29-6060 Revision 01 or A300-29-

9009 Revision 02 as applicable to aeroplane model and send it to 

AIRBUS (E-mail: sb.reporting@airbus.com). 

Ref. Publications: 

AIRBUS Service Bulletins: 

A300-29-0124 Revision 02 

A310-29-2097 Revision 01 

A300-29-6060 Revision 01 

A300-29-9009 Revision 02 

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 15 July 2009 as PAD 09-092 for consultation until 

29 July 2009. 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. 

4. For any question concerning the technical content of the requirements in 

this AD, please contact: 

AIRBUS SAS – EAW (Airworthiness Office) 

Telephone + 33 5 61 93 36 96, Fax + 33 5 61 93 44 51