### 40220 Tarnos

- France
Tel. +33 (0)5 59 74 40 00 Fax. (+33) (0)5 59 74 45 15



# MANDATORY SERVICE BULLETIN

Applicable variants: ARRIEL 2 B

- B1

- B1A

- B1B

- C

- C1

- C2

- D

- E

- N

- S1

- S 2 

# ARRIEL 2 No. 292 72 2861

Object: Accessory gearbox front cover.

Detection of wear on the 41

- or 42

- tooth gear front bearing housing.

The technical information contained in this document has been approved under Design Organization Approval No. EASA.21J.07 0.

Date on which this Mandatory SB becomes effective and must systematically be complied with, according to the conditions of application.

Applicable from JUNE 2015

If these resources are available any earlier, the M andatory SB may be applied prior to th e effectivity date.



## Version : A



# SB_292_72_2861_EN - A <April 24, 2015> - 1 / 12

# MANDATORY SERVICE BU LLETIN

Applicable variants: ARRIEL 2 B

- B1

- B1A

- B1B

- C

- C1

- C2

- D

- E

- N

- S1

- S2 § 1

- 1 / 1 

## 1. GENERAL

Purpose 1.1.

WARNING DANGER : FAILURE TO APPLY THIS MANDATORY SERVICE BULLETIN MAY LEAD TO AN UNCOMMANDED IN

FLIGHT ENGINE SHUT

- DOWN WHICH, ON A SINGLE

- ENGINE HELICOPTER, MAY LEAD TO AN EMERGENCY AUTOROTATION LANDING. 

### Introduce monitoring to detect wear on the accessory gearbox front cover at the housing of the 41

- or 42

- tooth gear front bearing.

Reason 1.2.
TURBOMECA has been informed of an uncommanded in

- flight shut

- down following rupture of the 41

- tooth gear, which forms part of the bevel gear of the accessory gearbox (module M01). Investigation into this event reveale d that the wear on the housing of the front bearing of this gear is a major contributing factor to this rupture. Analysis of the engine history demonstrated that the aluminum content revealed by the Spectrometric Oil Analysis (SOA) check evolved significan tly in the hours preceding the event.
The SOA check described in this mandatory SB therefore enabled a high aluminum content to be detected, the origin of which may be the wear on the housing of the 41

- or 42

- tooth gear front bearing. This SOA check is the first step to reduce the risk and will be completed or mended in a second step by a check which could be used to measure wear on the housing of the 41

- or 42

- tooth gear front bearing

. Description 1.3. This mandatory SB consists in performing a periodic SOA check to monitor the evolution of the aluminum
content

. Approved by 1.4. The technical information contained in this document has been approved under Design Organization Approval No. EASA.21J.070.

This Mandatory SB is subject to an Airworthiness Directive.
Conditions of application 1.5. The application conditions of this Mandatory SB are defined respectively in:

- Chapter §2 regarding application at the operator’s site or by a qualified Maintenance Center for l evel 1, 2.

- Chapter §3 regarding application by a qualified Maintenance Center for level 3.

- Chapter §4 regarding application at a TURBOMECA

- approved Repair Center.
Update history 1.6. Not applicable.



### END of section §1

" General "



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# MANDATORY SERVICE BU LLETIN

Applicable variants: ARRIEL 2 B

- B1

- B1A

- B1B

- C

- C1

- C2

- D

- E

- N

- S1

- S2 § 2

- 1 / 8 

## 2. APPLICATION AT THE OPERATOR’S SITE OR BY A QUALIFIED MA INTENANCE CENTER FOR LEVEL 1, 2

WARNING DANGER : FAILURE TO APPLY THIS MANDATORY SERVICE BULLETIN MAY LEAD TO AN UNCOMMANDED IN

FLIGHT ENGINE SHUT

- DOWN WHICH, ON A SINGLE

- ENGINE HELICOPTER, MAY LEAD TO AN EMERGENCY AUTOROTATION LANDING.


### Actions to be performed 2.1. Perform an SOA check as per paragraph 2.3.2.
Effectivity and compliance times 2.2.

ENGINE/VARIANT CODE COMPLIANCE CONDITION S FOR ENGINES IN SERVI CE

ARRIEL 2B

- 2B1

- 2B1A

- 2B1B

1

- A 1. Identification of the type of cover in compliance with § 2.3.1.1: A pplication during the next maintenance operation that requires the engine cowling to be opened

. 2. SOA check for accessory gearboxe s which meet the conditions of § 2.3.1.2 : A pplication before 50 operating hours is reached (counted from receipt of this Mandatory SB), or within 50 hours after installation of the module, then every 100 operating hours. ARRIEL 2C

- 2C1

- 2C2

ARRIEL 2D

ARRIEL 2E

ARRIEL 2N

ARRIEL 2S1

- 2S2


### Application of this Mandatory SB is considered mandatory as a result of a technical requirement which might affect flight safety of engines in service. It may be done as defined by the effectivity code given in the table above.
Conditions of application fo r engines in service 2.3.

2.3.1. Logic

- based diagram pertaining to the conditions of Mandatory SB application

2.3.1.1. Identification of the type of cover

This type of casing cover is identified by a visual inspection of the engine. Depending on the engine variant (and therefore the type of front mount), the casing cover P/N may or may not be legible: it is engraved on the lower RH side of the casing cover (viewed from front of engine), below the HMU. If the P/N is not legible, the surface condition will help to discrimi nate between "machined" casing covers and " casted " casing covers

- see Figure 1:

 " Casted " casing covers have a rough/granular surface,

 "Machined" casing covers have a smooth surface. If in doubt, contact your Field Representative.

2.3.1.2. SOA check

The SOA check is only applicable to module M01 with a TSN/TSO of over 800 hours and equipped with a "machined" accessory gearbox casing cover P/ N 0292120650.



# SB_292_72_2861_EN - A <April 24, 2015> - 3 / 12

# MANDATORY SERVICE BU LLETIN

Applicable variants: ARRIEL 2 B

- B1

- B1A

- B1B

- C

- C1

- C2

- D

- E

- N

- S1

- S2 § 2

- 2/ 8 

### Concerned by the SOA check "Machined" casing cover installed on the engine with its smooth visual appearance

Not concerned by the SOA check

" Casted " casing cover installed on the engine with its granular visual appearance

Figure 1: Identification of a "machined" casing cover



# SB_292_72_2861_EN - A <April 24, 2015> - 4 / 12

# MANDATORY SERVICE BU LLETIN

Applicable variants: ARRIEL 2 B

- B1

- B1A

- B1B

- C

- C1

- C2

- D

- E

- N

- S1

- S2 § 2

- 3 / 8 

### 2.3.2. Procedure

* : If the engine is already the subject of SOA follow

- up and the aluminum content is present in the laboratory reports, the criteria of § 2.4.2.2. are applicable to the last recording 

### of module M01 with a TSN/TSO of over 80 0 h ou rs.



# SB_292_72_2861_EN - A <April 24, 2015> - 5 / 12

# MANDATORY SERVICE BU LLETIN

Applicable variants: ARRIEL 2 B

- B1

- B1A

- B1B

- C

- C1

- C2

- D

- E

- N

- S1

- S2 § 2

- 4 / 8 

### Accomplishment Instructions 2.4.

2.4.1. Implementation

The spectrometric oil analysis check following application of this Mandatory SB does not necessitate removing the engine from the helicopter.

2.4.2. Operating mode

WARNING DANGER : FAILURE TO APPLY THIS MANDATOR Y SERVICE BULLETIN MAY LEAD TO AN UNCOMMANDED IN

FLIGHT ENGINE SHUT

- DOWN WHICH, ON A SINGLE

- ENGINE HELICOPTER, MAY LEAD TO AN EMERGENCY AUTOROTATION LANDING.



### 2.4.2.1. Take an oil sample and send it to an analysis laboratory, refer to the relevant ARRIEL 2

Maintenan ce Manual, task 71

- 02

- 08

- 280

- 801

- A01. Note : When sending, specify that the aluminum content should be mentioned in the analysis report.

2.4.2.2. If the data is available, calculate the corrected aluminum content as per the formula of task

71

- 02

- 08

- 280

- 802

- A01, §5.B.1.b., otherwise apply the following criteria to the raw result of the SOA check.

2.4.2.3. Action dependent on the result of the SOA check:

 A luminum content < 0.8 ppm: Repeat the SOA check within 100 hours

 A luminum content > 1.4 ppm: Replace module M01 within 50 hours

 0.8 ppm ≤ A luminum content ≤ 1.4 ppm: Repeat the SOA check within 50 hours in one of the following laboratories, without performing draining beforehand:

Laboratory Country

Aviation Laboratories UNITED STATES Corporation d'Entretien Prédictif CANADA Gough Group NEW ZEALAND

IHI Jet Service Co JAPAN
Intertek West Lab AS NORWAY ITS Testing Services UNITED KINGDOM

Jet Care UNITED STATES
Naval Maintenance Establishment NETHERLANDS

RUAG SWITZERLAND

SGS Vernolab FRANCE

SPECTRO UNITED KINGDOM

SPECTRO INC UNITED STATES

SPECTRO OIL AG SWITZERLAND

TEKNIKER SPAIN



# SB_292_72_2861_EN - A <April 24, 2015> - 6 / 12

# MANDATORY SERVICE BU LLETIN

Applicable variants: ARRIEL 2 B

- B1

- B1A

- B1B

- C

- C1

- C2

- D

- E

- N

- S1

- S2 § 2

- 5 / 8 

### 2.4.3. Reconditioning and checks
Top up the oil level, refer to the relevant ARRIEL 2 Helicopter Manual.

2.4.4. Identification

2.4.4.1. Identification of the casted casing cover

2.4.4.1.1. Record the application of this Mandatory SB in section "E" of the en gine log book.

2.4.4.1.2. Record the application of the Mandatory SB in the module M01 log card (FMFE),

indicating " Casted casing cover".

2.4.4.1.3. Notify TURBOMECA that this Mandatory SB has been applied by returning the fully

completed compliance certificate (Appendix 2.1)

2.4.4.2. S OA check

2.4.4.2.1. Record the application of this Mandatory SB in section "E" of the engine log book.

2.4.4.2.2. Record the application of this Mandatory SB in the module M01 log card (FMFE),

indicating the module M01 TSN and the aluminum content in ppm.

2.4.4.2.3. Notify TURBOMECA that this Mandatory SB has been applied by returning the fully

completed compliance certificate (Appendix 2.1)

2.4.4.2.4. If necessary, inform TURBOMECA of the replacement of module M01 by returning

the fully completed compliance certificate (Appendix 2.2 of this Mandator y SB).

2.4.5. Routine maintenance
SOA check to be performed every 100 hours after the first check (or 50 hours depending on the aluminum content ).



# SB_292_72_2861_EN - A <April 24, 2015> - 7 / 12

# MANDATORY SERVICE BU LLETIN

Applicable variants: ARRIEL 2 B

- B1

- B1A

- B1B

- C

- C1

- C2

- D

- E

- N

- S1

- S2 § 2

- 6 / 8 

### Material information 2.5.

2.5.1. List of supplies

Not applicable.

2.5.2. Supply conditions
Order supplies as needed from:
your local TURBOMECA Support Center

or

TURBOMECA Support and Services Division Commercial Department 40220 TARNOS

- France Fax no. +33 (0) 5 59 74 45 11.
Manpower 2.6.

- Personnel: 1 mechanic

- Time required: 0.5 hours
Tooling and/or products 2.7.

Refer to task 71

- 02

- 08

- 280

- 801

- A01 of the relevant ARRIEL 2 M aintenance Manual.

WEIGHT AND BALANCE 2.8. Not applicable.

Publication references 2.9.

Document Engine P/N

Maintenance Manual (MM) ARRIEL 2B X 292 M5 450 2

ARRIEL 2B1 X 292 N5 450 2

ARRIEL 2B1A X 292 P4 450 2
ARRIEL 2C X 292 M1 450 2
ARRIEL 2C1 X 292 N4 450 2
ARRIEL 2C2 X 292 P6 450 2

ARRIEL 2D X 292 R1 450 2

ARRIEL 2E X 292 R2 300 2

ARRIEL 2N X 292 N2 450 2
ARRIEL 2S1 X 292 L0 301 2
ARRIEL 2S2 X 292 P5 451 2

Spare Parts Catalog (SPC) ARRIEL 2B X 292 M5 700 2

ARRIEL 2B1 X 292 N5 700 2

ARRIEL 2B1A X 292 P4 700 2
ARRIEL 2C X 292 M1 700 2
ARRIEL 2C1 X 292 N4 700 2
ARRIEL 2C2 X 292 N6 700 2

ARRIEL 2D X 292 R1 700 2

ARRIEL 2E X 292 R2 700 2

ARRIEL 2N X 292 N2 700 2
ARRIEL 2S1 X 292 L0 700 2
ARRIEL 2S2 X 292 P5 700 2
Relevant Helicopter Maintenance Manual.



# SB_292_72_2861_EN - A <April 24, 2015> - 8 / 12

# MANDATORY SERVICE BU LLETIN

Applicable variants: ARRIEL 2 B

- B1

- B1A

- B1B

- C

- C1

- C2

- D

- E

- N

- S1

- S2 § 2

- 7 / 8 

# Objet : Attestation d’application du SB Impératif n° 292 72 2861. Subject: Mandatory SB No. 292 72 2861 compliance certificate.

Important / Important notice : Après application des instructions spécifiées dans ce SB Impératif, veuillez compléter la présente attestation et la retourner par courrier ou courriel ou fax à : After application of the instructions specified in this Mandatory SB, please complete this certificate and return it by mail or email or fax it to: TURBOMECA, Equipe Administration Base installée / Fleet Data Administrator Team, BP 25
40220 TARNOS

- France
Fax n° / No. +33 (0) 5 59 74 46 95

– Email: fleetdata@turbomeca.fr

Information concernant le matériel / Equipment information

U tili s at e u r Customer N ° Appareil Aircraft S/N

N/S

- S/N Ref.

- P/N TSN* TSO* CSN* CSO*

Moteur Engine

Module M01 inspecté Inspected module M01

* TSN = Time Since New (Heures depuis neuf) TSO = Time Since Overhaul (Heures depuis RG) CSN = Cycles Since New (Cycles depuis neuf) CSO = Cycles Since Overhaul (Cycles depuis RG)



### Couvercle usiné Machined casing OUI / Yes NON / NO

PN Couvercle usiné Machined casing P / N P/N: __________________________

Je certifie que le moteur identifié ci

- dessus a été contrôlé selon les directives de ce SB Impératif. I certify that the above

- mentioned engine has been checked according to the directives given in this Mandatory SB.

Date [JJ/MMMM (en lettre)/AAAA ou/or DD/MMMM (letters)/YYYY] 

### Nom / Name Fonction / Job title



### ANNEXE 2.1 / APPENDIX 2.1 Signature:



# SB_292_72_2861_EN - A <April 24, 2015> - 9 / 12

# MANDATORY SERVICE BU LLETIN

Applicable variants: ARRIEL 2 B

- B1

- B1A

- B1B

- C

- C1

- C2

- D

- E

- N

- S1

- S2 § 2

- 8 / 8 

# Objet : Attestation de remplacement du module M01. Subject: Compliance certificate for replacement of module M01.

Important / Important notice : Après application des instructions spécifiées dans ce SB Impératif, veuillez compléter la présente attestation et la retourner par courrier ou courriel ou fax à : After application of the instructions specified in this Mandatory SB, please complete this certificate and return it by mail or email or fax it to: TURBOMECA, Equipe Administration Base installée / Fleet Data Administrator Team, BP 25
40220 TARNOS

- France 

### Fax n° / No. +33 (0) 5 59 74 46 95

– Email: fleetdata@turbomeca.fr

Information concernant le matériel / Equipment information

U tilisateur Customer N ° Appareil Aircraft S/N

N/S

- S/N Ref.

- P/N TSN* TSO* CSN* CSO*

Moteur Engine

Module M01 déposé Removed module M01

Module M01 installé Installed module M01

* TSN = Time Since New (Heures depuis neuf) TSO = Time Since Overhaul (Heures depuis RG) CSN = Cycles Since New (Cycles depuis neuf) CSO = Cycles Since Overhaul (Cycles depuis RG)



### Opération effectuée par / Work performed by:

Je certifie que le module M01 identifié ci

- dessus a été installé selon les directives de ce SB Impératif. I certify that the above

- mentioned module has been fitted according to the directives given in this Mandatory SB.

Date [JJ/MMMM (en lettre)/AAAA ou/or DD/MMMM (letters)/YYYY] 

### Nom / Name Fo nction / Job title



### ANNEXE 2.2 / APPENDIX 2.2 Signature:

END of section §2

" Application at the operator’s site or by a qualified Maintenance Center for level 1, 2 "



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# MANDATORY SERVICE BU LLETIN

Applicable variants: ARRIEL 2 B

- B1

- B1A

- B1B

- C

- C1

- C2

- D

- E

- N

- S1

- S2 § 3

- 1 / 1 

## 3. APPLICATION BY A QUA LIFIED MAINTENANCE C ENTER FOR LEVEL 3
Not applicable. Indeed, this check requires the sampling and analysis of oil with a significant number of operating hours in the engine , and this is not possible in a Maintenance Center, even during bench testing.



### END of section §3

“ Application by a qualified Maintenance Center for level 3 ”



# SB_292_72_2861_EN - A <April 24, 2015> - 11 / 12

# MANDATORY SERVICE BU LLETIN

Applicable variants: ARRIEL 2 B

- B1

- B1A

- B1B

- C

- C1

- C2

- D

- E

- N

- S1

- S2 § 4

- 1 / 1 

## 4. APPLICATION AT A TUR BOMECA

- APPROVED REPAIR CENT ER
Not applicable. Indeed, this check requires the sampling and analysis of oil with a significant number of operating hours in the engine , and this is not possible in a Repair Center, even during bench testing.



### End of section §4

“ Application by a TURBOMECA

- approved Repair Center ”



# SB_292_72_2861_EN - A <April 24, 2015> - 12 / 12