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# MANDATORY SERVICE BULLETIN

ARRIEL 1 No. 292 72 0839

Subject: 41/23 tooth bevel gear assembly of the accessory gearbox (module M01). Application of TI No. 292 72 0839 or No. 292 72 0840 referencing vibration check.

The technical information contained in this document is approved under the Design Organization Approval No. EASA.21J.070.



## Version: B

Reason for update: Modification of the effectivity code.



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# MANDATORY SERVICE BULLETIN

1. Compliance conditions

CAUTION: FAILURE TO APPLY THIS MANDATORY SERVICE BULLETIN MAY LEAD TO AN UNCOMMANDED IN-FLIGHT ENGINE SHUT-DOWN WHICH, ON A SINGLE-ENGINE HELICOPTER, LEADS TO AN EMERGENCY AUTOROTATION LANDING. 

### A. Mandatory Service Bulleti n (SB) effectivity date Date on which this Mandatory SB becomes effective and must systematically be complied with, according to the conditions of application. This date corresponds to when all resources needed to perform the procedure (parts, tools, documentation, etc.) will be available. If these resources are available any earlier, the Mandatory SB may, as an exception, be applied prior to the effectivity date.

NOVEMBER 2013


### B. Effectivity 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 below.
Effectivity Code *
ARRIEL 1B ARRIEL 1D - 1D1 1-B

* The actions and conditions of application are described in paragraph 5.

Note 1: This Mandatory SB does not apply if this version (version B) or its version A (recommended SB) is already indicated on module M01 log card. Note 2: This Mandatory SB does not apply if the achievement of the 41 tooth gear vibration check is indicated on module M01 log card, refer to SL 2891/13/ ARRIEL1. Note 3: This Mandatory SB does not apply if the serial number of module M01 is shown in the list on Figure 01. 

## 2. Purpose

CAUTION: FAILURE TO APPLY THIS MANDATORY SERVICE BULLETIN MAY LEAD TO AN UNCOMMANDED IN-FLIGHT ENGINE SHUT-DOWN WHICH, ON A SINGLE-ENGINE HELICOPTER, LEADS TO AN EMERGENCY AUTOROTATION LANDING. The purpose of this Mandatory SB is to check the meshing quality of 41/23 tooth bevel gear of accessory gearbox (module M01). 

## 3. Reason TURBOMECA has been informed of several uncommanded in-flight shutdown events following rupture of 41 tooth gear forming part of 41/23 tooth bevel gear of accessory gearbox (module M01). Investigation into these events revealed that the meshing quality of this bevel gear could be a contributing factor in the rupture.



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# MANDATORY SERVICE BULLETIN

4. Description This Mandatory SB consists of applying a Technical Instruction (TI) to check meshing vibration level of 41/23 tooth bevel gear of module M01. 

## 5. Required actions and compliance times A. At the operator's site Application before the 31 st of October 2016. Apply TI X 292 72 0839 to check meshing vibration level of 41/23 tooth bevel gear of module M01 according to paragraph 6. Consider the vibration check results after receiving the measurement report: refer to paragraph 6.B.1. 

### B. At a TURBOMECA-approved Service Center or at a TURBOMECA-approved Maintenance Center Application before the 31 st of October 2016. Apply TI X 292 72 0840 to check meshing vibration level of 41/23 tooth bevel gear of module M01 if task 71-02-15-760-801-A01 of the Maintenance Manual is applied: refer to paragraph 6. 

### C. At a TURBOMECA-approved Repair Center Not applicable. 

## 6. Accomplishment Instructions A. Implementation The application of this Mandatory SB does not necessitate removing the engine from the helicopter. (1) At the operator's site (a) Apply TI X 292 72 0839 to check meshing vibration level of 41/23 tooth bevel gear of module M01. (b) Identify module M01 status in the FMFE of module M01, refer to paragraph 6.D.1 (c) Send an acknowledgement of receipt for t he measurement report to your NORIA coordinator, refer to paragraph 7.C. (2) At a TURBOMECA-approved Service Center or at a TURBOMECA-approved Maintenance Center If bench testing according to task 71-02-15-760-801-A01 of the Maintenance Manual: (a) Apply TI X 292 72 0840 to check meshing vibration level of 41/23 tooth bevel gear of module M01. (b) Identify module M01 status in the FMFE of module M01, refer to paragraph 6.D.2. (3) At a TURBOMECA-approved Repair Center Not applicable.



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# MANDATORY SERVICE BULLETIN

B. Operating instructions (1) At the operator's site (a) Apply TI X 72 292 0839. (b) Actions according to the vibration check result specified in the email sent by Turbomeca or in the report generated by the B&K server: 1 Level 1 - Green indicator: keep module M01 in service. 2 Level 2 - Yellow indicator: remove module M01 within 150 hours or 3 months (first limit reached). 3 Level 3 - Orange indicator: remove module M01 within 25 hours (or earlier, depending on the recommendations made by Turbomeca) or 3 months (first limit reached). 4 If "measure invalid", contact your TURBOMECA representative. (c) Send an acknowledgement of receipt by ema il or fax to your NORIA coordinator, refer to paragraph 7.C, confirming that the status of module M01 has been taken into account. (2) At a TURBOMECA-approved Service Center or at a TURBOMECA-approved Maintenance Center If maintenance task 71-02-15-760-801-A01 is applied: (a) Apply TI X 72 292 0840. (b) Actions according to the vibration check result: 1 Compliant result: release module M01 into service. 2 Non-compliant result: return module M01 to a Repair Center. (3) At a TURBOMECA-approved Repair Center Not applicable. 

### C. Reconditioning and checks (1) At the operator's site Not applicable. (2) At a TURBOMECA-approved Service Center or at a TURBOMECA-approved Maintenance Center Refer to relevant ARRIEL 1 Maintenance Manual, task 05-50. (3) At a TURBOMECA-approved Repair Center Not applicable.


### D. Identification (1) At the operator's site (a) Record the application of this Mandatory SB on the FMFE of the module M01 indicating the measurement level as follows: “level 1 – green”, “level 2 – yellow” or “level 3 – orange”, as well as the module M01 TSN at the time of the measurement. (b) If necessary, notify TURBOMECA that standard exchange of module M01 has been performed by returning the fully completed compliance certificate (Appendix). (2) At a TURBOMECA-approved Service Center or at a TURBOMECA-approved Maintenance Center (a) If the vibration check result is compliant, record the application of this Mandatory SB on the module M01 log card.



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# MANDATORY SERVICE BULLETIN

(b) If the vibration check result is not compliant, notify TURBOMECA that standard exchange of module M01 has been performed by returning the fully completed compliance certificate (Appendix). (3) At a TURBOMECA-approved Repair Center Not applicable.


### E. Routine maintenance No modification to the routine maintenance. 

## 7. Material information

A. Basic information The parts list required for the application of this Mandatory SB is for one engine. 

### B. List of parts (1) At the operator's site Refer to TI X 292 72 0839, to the Maintenance Manual and/or to the relevant ARRIEL 1 Spare Parts Catalog. (2) At a TURBOMECA-approved Service Center or at a TURBOMECA-approved Maintenance Center Refer to TI X 292 72 0840, to the relevant ARRIEL 1 Maintenance Manual and/or Spare Parts Catalog. (3) At a TURBOMECA-approved Repair Center Not applicable.



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# MANDATORY SERVICE BULLETIN

C. Supply conditions Supply of parts will be managed by:

For North and Central America TURBOMECA-Noria

Team Dallas 2709 Forum Drive Grand Prairie, TX 75052 – USA Fax : +1 972 606 76 68 noria-dallas@turbomeca.com

Team Canada 11800, rue Helen-Bristol J7N 3G8 QC MIRABEL –Canada Fax : +1 450 476 1449 noria-mirabel@turbomeca.ca

Team Mexico Montes Urales 505 Piso 3 Colonia Lomas de Chapultepec 11000 – Mexico DF noria-mexico@turbomeca.com.mx For Africa, Europe, Middle East TURBOMECA-Noria

Team Tarnos DVO Service NORIA 40220 TARNOS – France Fax : +33 (0) 5 59 74 45 72 noria-tarnos-arriel1@ turbomeca.fr

Team UK Concorde Way Segensworth North, Fareham Hants PO15 5RL - United Kingdom noria-tmuk@turbomeca.co.uk

Team Hamburg Borsteler Chaussee 43 22453 Hamburg – Germany Fax:+49 40 500 216 61 noria-hamburg@turbomeca.de For South America TURBOMECA-Noria

Team Rio Rua Capitão Guynemer, 1626 – Xerém CEP : 25250-130 - Duque de Caxias - RJ – Brasil Fax : +55 21 2679 2794 noria-rio@turbomeca.com.br

For Australasia, Oceania, Japan TURBOMECA-Noria
Team Sydney 115 Wackett St, Bankstown Airport Bankstown, NSW 2200 – Australia Fax : +61 2 9791 6708 noria-sydney@turbomeca.com.au For Asia Pacific TURBOMECA-Noria

Team Singapore 63 Loyang Way, Singapore 508753 Fax:+65 6545 4978 noria.singapore@turbomeca.com.sg



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# MANDATORY SERVICE BULLETIN

8. Manpower A. At the operator's site

- Personnel: One mechanic and one person qualified to perform a ground run check.

- Time required: 4 man-hours. 

### B. At a TURBOMECA-approved Service Center or at a TURBOMECA-approved Maintenance Center

- Personnel of approved Repair/Maintenance Center.

- Time determined by the Repair/Maintenance Center as being appropriate for this level of

intervention. 

### C. At a TURBOMECA-approved Repair Center Not applicable 

## 9. Tooling and/or products A. At the operator's site

- Mechanic's standard tooling.

- Refer to TI X 292 72 0839. 

### B. At a TURBOMECA-approved Service Center or at a TURBOMECA-approved Maintenance Center

- Mechanic's standard tooling.

- Refer to TI X 292 72 0840. 

### C. At a TURBOMECA-approved Repair Center Not applicable. 

## 10. Weight and balance Not applicable. 

## 11. Publication references

- ARRIEL 1B Maintenance Manual............................................................ Ref. X 292 65 452 2.

- ARRIEL 1D Maintenance Manual ........................................................... Ref. X 292 E5 452 2.

- ARRIEL 1D1 Maintenance Manual ......................................................... Ref. X 292 G2 452 2.

- ARRIEL 1B Spare Parts Catalog............................................................. Ref. X 292 65 702 2.

- ARRIEL 1D Spare Parts Catalog ............................................................ Ref. X 292 E5 702 2.

- ARRIEL 1D1 Spare Parts Catalog .......................................................... Ref. X 292 G2 702 2.

- Technical Instruction .............................................................................. Ref. X 292 72 0839.

- Technical Instruction .............................................................................. Ref. X 292 72 0840. 

## 12. Approval The technical information contained in this document is approved under the Design Organization Approval No. EASA.21J.070. This Mandatory SB is subject to an Airworthiness Directive.



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# MANDATORY SERVICE BULLETIN

Variante/

Variant SN M01/ NS M01 Variante/ Variant SN M01/ NS M01 1B 59 1D1 9707 1B 109 1D1 9758 1B 240 1D1 9808 1B 331 1D1 9878 1B 421 1D1 9931 1B 530 1D1 9985 1B 963 1D1 10000 1B 987 1D1 10077 1B 4171 1D1 12034 1B 4173 1D1 13039 1B 4206 1D1 13051 1B 4218 1D1 13055 1B 4345 1D1 13097 1B 4368 1D1 13163 1B 4373 1D1 13243 1B 4380 1D1 13282 1B 4437 1D1 13377 1B 4509 1D1 13422 1D 7017 1D1 13444 1D 9903 1D1 13457 1D1 1089 1D1 13458 1D1 2207 1D1 13462 1D1 7126 1D1 13463 1D1 7167 1D1 13464 1D1 9076 1D1 13465 1D1 9079 1D1 13466 1D1 9086 1D1 13467 1D1 9114 1D1 13468 1D1 9196 1D1 13469 1D1 9211 1D1 13470 1D1 9321 1D1 13471 1D1 9329 1D1 13473 1D1 9351 1D1 13474 1D1 9356 1D1 13475 1D1 9385 1D1 13476 1D1 9405 1D1 13477 1D1 9420 1D1 13478 1D1 9451 1D1 13479 1D1 9465 1D1 13480 1D1 9525 1D1 13481 1D1 9558 1D1 13482 1D1 9599 1D1 13484 1D1 9657 1D1 20955 1D1 9692 1D1 9931TEC 1D1 9704 

### FIGURE 01 - Liste des modules M01 non concernés par ce SB Impératif FIGURE 01 - List of modules M01 that are not concerned by the application of this Mandatory SB



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# MANDATORY SERVICE BULLETIN

Objet : Attestation de remp lacement du module M01 Subject: Compliance certificate for module M01 replacement

Important / Important notice :
Après application des instructions spécifiées dans ce SB Impératif, veuillez compléter la présente attestation et la retourner auprès de votre coordinateur NORIA local par courrier ou courriel ou fax, se reporter paragraphe 7.C

. After application of the instructions specified in this Ma ndatory SB, please complete this certificate and return it to your local coordinator NORIA by mail or email or fax, refer to paragraph. 7.C.

Information concernant le matériel / Equipment information

Utilisateur Customer N° Appareil Aircraft S/N

N/S - S/N Réf. - 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 identifié ci-dessus a été in stallé selon les directives de ce SB Impératif. I certify that the above-mentioned module has been inst alled according to the directives given in this Mandatory SB.

Date [JJ / MMMM (en lettre) / AAAA

ou/or DD / MMMM (letter) / YYYY] Nom / Print name Fonction / Job title

ANNEXE / APPENDIX Signature :



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