### T.F.S. No. 00000442

Approved under EASA DOA No. 21J.056 Page 1/12

2008.01.04

This document is available on the internet: www.eurocopter.com/techpub EUROCOPTER

DIRECTION TECHNIQUE SUPPORT

13725 MARIGNANE C EDEX F RANCE



# EMERGENCY 

# ALERT SERVICE BULLETIN

SUPER PUMA NUMBER VERSIONS

Civil: C, C1, L, L1, L2 

# AS332 53.01.58 Military: B, B1, M, M1, F1



# AS532 53.00.58 Military: AC, AL, SC, UC, UE, UL, A2, U2



# EC225 53A012 Civil : LP



# EC725 53A011 Military: AP



### SUBJECT: FUSELAGE

Check for presence of the blind hole in the TGB attachment fittings

ATA : 53

REVISION No. DATE OF APPROVAL DATE OF ISSUE

Revision 0 On: December 5, 2007 2007.12.05 Revision 1 On: January 04, 2008 2008.01.04

### T.F.S. No. 00000442

Approved under EASA DOA No. 21J.056 Page 2/12

2008.01.04 

### 1. PLANNING INFORMATION

1.A. EFFECTIVITY

1.A.1. Helicopters / Installed equipment

- Tail gear box (TGB) attachment fittings, all part numbers - This ALERT SERVICE BULLETIN applies to helicopters with serial numbers below S/N 2680 and helicopters with serial numbers from S/N 9000 (inclusive) to S/N 9009 (inclusive)

.

NOTE

Helicopters with serial numbers above S/N 2680 (inclusive) are not concerned by this ALERT SERVICE BULLETIN, except helicopters with serial

numbers from S/N 9000 to S/N 9009.

1.A.2. Non-installed equipment

Not applicable.



### 1.B. ASSOCIATED REQUIREMENTS

Not applicable.



### 1.C. REASON

To make sure that the blind hole is present in the TGB attachment fittings.

Revision 0 and Revision 1 of this ALERT SER VICE BULLETIN form the subject of DGAC

Airworthiness Directive No. F-2007-027.

Revision 1 of this ALERT SERVICE BULLETIN give s the characteristics of the additional washer specified in paragraph 2.A. instead of the washer referenced EN 2138-12020.

Compliance with Revision 1 of this ALERT SER VICE BULLETIN does not affect compliance with

Revision 0.



### 1.D. DESCRIPTION

During a scheduled maintenance ch eck (750-hour inspection), inte rference was discovered between

the end of the threaded section of the TGB a ft attachment bolt and the structure fitting. Investigation revealed that this interference was due to the missing 13 mm Ø blind hole which provides clearance for the bolt in the structure fitting. (See Figure 1 Detail A: Compliant fitting and Detail B: Non-compliant fitting).

Such interference can cause insufficient axial ti ghtening of the TGB casing even if the tightening torque applied to the attachment bolt is correct.

### T.F.S. No. 00000442

Approved under EASA DOA No. 21J.056 Page 3/12

2008.01.04 In fact, after application of the torque load, the bolt may touch the bottom of the hole in the fitting before it correctly tightens the TGB casing attachment lug. Insufficient tightening can cause damage to this attachment and give rise to crack initiation under the

bolt head before the end of the TBO of the TGB is reached.

EUROCOPTER has undertaken quality actions with t he manufacturer of these fittings in order to deal with this anomaly. In order to check the integrity of this attachment which, if it fails, can fi nally lead to the loss of the TGB, EUROCOPTER renders compliance with the instru ctions given in this ALERT SERVICE BULLETIN mandatory until these actions are taken.



### 1.E. COMPLIANCE

EUROCOPTER renders compliance with th is ALERT SERVICE BULLETIN mandatory.

1.E.1. Compliance at the works

1.E.1.a. On helicopters: Not applicable.

1.E.1.b. On non-installed equipment: Not applicable.

1.E.2. Compliance in operation: By the operator:

1.E.2.a. On helicopters / installed equipment:

- On the TGB aft attachment fitting:

. Comply with paragraph 2.B.2 within 50 flying hours following receipt of revision 0 of this

ALERT SERVICE BULLETIN,

- if the measurement is equal to or greater than 81 mm:

. comply with paragraph 2.B.2.a,

- if the measurement is less than 81 mm:

. comply with paragraph 2.B.2.b,

then - comply with paragraph 2.B.3. no later than wi thin the next 825 flying hours, but at the latest

by December 31, 2008.

- On the TGB forward attachment fitting:

. Comply with paragraph 2.B.4 within 50 flying hours following receipt of revision 0 of this

ALERT SERVICE BULLETIN,

- if both measurements are equal to or greater than 81 mm:

. comply with paragraph 2.B.4.a,

- if one or both measurements is/are less than 81 mm:

. comply with paragraph 2.B.4.b. on the attachment(s) concerned,

then - comply with paragraph 2.B.5. no later than wi thin the next 825 flying hours, but at the latest

by December 31, 2008.

### T.F.S. No. 00000442

Approved under EASA DOA No. 21J.056 Page 4/12

2008.01.04 1.E.2.b. On non-installed equipment: Not applicable.



### 1.F. APPROVAL

Approval is limited to civil version helicopte rs subject to an Airworthiness Certificate.

The technical information contained in revision 0 of this ALERT SERVICE BULLETIN was approved
on December 5, 2007under the authority of EASA Design Org anisation Approval No. 21J.056.

The technical information contained in revision 1 of this ALERT SERVICE BULLETIN was approved on January 04, 2008 un der the authority of EASA Design Or ganisation Approval N°21 J.056.



### 1.G. MANPOWER

Qualification: Mechanic or ai rcraft structure technician.

Time for the operations: Approximately 1 hour.



### 1.H. WEIGHT AND BALANCE

Not applicable.



### 1.I. EFFECT ON ELECTRICAL LOADS

Not applicable.



### 1.J. SOFTWARE MODIFICATION EMBODIMENT STATE

Not applicable.



### 1.K. REFERENCES

Aircraft Maintenance Manual (MMA) Ta sks: 64-20-00-021 and 64-20-00-421. Maintenance Manual (MET) Work Card: 64.20.00.401. Maintenance Program.



### 1.L. OTHER DOCUMENTS CONCERNED

Not applicable.



### 1.M. TOOLING CONCERNED

Not applicable.

### T.F.S. No. 00000442

Approved under EASA DOA No. 21J.056 Page 5/12

2008.01.04 

### 1.N. INTERCHANGEABILITY AND MIXABILITY OF PARTS

Not applicable.



### 2. ACCOMPLISHMENT INSTRUCTIONS

2.A. GENERAL

On installation of the TGB in accordance with MMA Task 64-20-00-421 or MET Work Card 64.20.00.401, we recommend that you fit (0.8 mm diameter) lockwire EN3628-080 instead of (1.25 mm diameter) lockwire EN3628-1,25, in order to avoid damage to the lock-hole on the casing. This replacement operation will s oon be incorporated in the documentation.

In the following procedure, the additional wa sher (2) to be used must have the following

characteristics: The additional washer (2) must be a cadmium-plated steel flat washer with a mechanical tensile strength T.S. ≥ 900 MPa

. Its inside diameter must be Ø i = 12.5 mm, tolerance H14

, Its outside diameter must be Ø

e = 24 mm, tolerance h14

, Its thickness must be e = 2 mm +/- 0.2

.



### NOTE

For information, the washer referenced EN 2138-12020 complies with the above characteristics.



### 2.B. OPERATIONAL PROCEDURE

2.B.1. Preliminary steps

- Set up appropriate access equipment provid ing access to the tail gear box (TGB). - Remove the TGB fairings.

2.B.2. Check of the TGB aft attachment fitting (a)

As per Figure 1 Detail A :

- Remove the TGB attachment bolt (c) as per MMA Task 64-20-00-021 or MET Work Card

64.20.00.401, but retain washer (d). - Use a depth gauge to measure dimension “x” between the top face of washer (d) placed on casing

assembly (e) and the bottom of aft fitting (a):

Interpretation of the results :

a) If the measurement is equal to or greater t han 81 mm: (Blind hole present, as shown on Figure 1 Detail A)

- Leave as is. - Fit TGB attachment bolt (c) complete with its washer (d) and torque-tighten to the recommended

torque load, as per MMA Task 64-20-00-421 or MET Work Card 64.20.00.401.

- Lock with lockwire. - Install the fairings. - Resume flights.

### T.F.S. No. 00000442

Approved under EASA DOA No. 21J.056 Page 6/12

2008.01.04 b) If the measurement is less than 81 mm: (Bli nd hole missing, as shown on Figure 1 Detail B)

- Check the condition of the end of the threaded section of bolt (c): (See Figure 1 Area 1)

. If no sign of chafing or contact mark is found.

- Fit bolt (c) complete with washer (d) and additional washer (2) and torque-tighten to the

recommended torque load, as per MMA Task 64-2 0-00-421 or MET Work Card 64.20.00.401.

. If signs of chafing or contact marks are found.

- Discard TGB attachment bolt (c). - Fit bolt (1) complete with washer (d) and additional washer (2) and torque-tighten to the

recommended torque load, as per MMA Task 64-2 0-00-421 or MET Work Card 64.20.00.401.

Position washer (d) under the bolt head. (See Figure 1 Detail B).

- Lock with lockwire. - Install the fairings.

- Please contact the EUROCOPTER Customer Service Technical Support Department by:

. Tel: +33(0)4.42.85.99.29 . Fax: +33(0)4.42.85.99.66 - Resume flights.

2.B.3. Returning the TGB aft attachment fitting (a) to conformity

- In order to define a repair solution for the fitting (replacing aft fitting (a) or drilling the blind hole),

please contact the EUROCOPTER Customer Service Technical Support Department by: . Tel: +33(0)4.42.85.99.29 . Fax: +33(0)4.42.85.99.66

2.B.4. Check of the TGB forward attachment fitting (b)

As per Figure 2 Detail A :

- Remove both TGB attachment bolts (c) as per MMA Task 64-20-00-021 or MET Work Card

64.20.00.401, but retain washers (d). - Use a depth gauge to measure dimension “x” between the top face of washer (d) placed on casing

assembly (e) and the bottom of forward fitting (b ) at the right and left attachment points: 

### CAUTION

### T.F.S. No. 00000442

Approved under EASA DOA No. 21J.056 Page 7/12

2008.01.04 Interpretation of the results :

a) If both measurements are equal to or greater than 81 mm: (Blind holes present, as shown on Figure 2 Detail A)

- Leave as is. - Fit TGB attachment bolts (c) complete with washers (d) and torque-tighten to the recommended

torque load, as per MMA Task 64-20-00-421 or MET Work Card 64.20.00.401.

- Lock with lockwire. - Install the fairings. - Resume flights.

b) If one or both measurements is/are less than 81 mm: (Blind hole missing, as shown on Figure 2 Detail B)

- Check the condition of the end of the threaded se ction of bolt(s) (c): (See Figure 2 Area 1)

. If no sign of chafing or contact mark is found.

- Fit bolt(s) (c) complete with washer(s) (d) and additional washer(s) (2) and torque-tighten to

the recommended torque load, as per MMA Task 64-20-00-421 or MET Work Card

64.20.00.401.

. If signs of chafing and contact marks are found.

- Discard the TGB attachment bolt(s) (c), as per MMA Task 64-20-00-021 or MET Work Card

64.20.00.401. - Fit bolt(s) (1) complete with washer(s) (d) and additional washer(s) (2) and torque-tighten to

the recommended torque load, as per MMA Task 64-20-00-421 or MET Work Card

64.20.00.401.

Position washer (d) under the bolt head. (See Figure 2 Detail B).

- Lock with lockwire. - Install the fairings.

- Please contact the EUROCOPTER Customer Service Technical Support Department by:

. Tel: +33(0)4.42.85.99.29 . Fax: +33(0)4.42.85.99.66 - Resume flights.

2.B.5. Returning the TGB forward a ttachment fitting (b) to conformity

- In order to define a repair solution for the fitting (replacing forward fitting (b) or drilling the blind

hole(s)), please contact the EUROCOPTER Custom er Service Technical Support Department by: . Tel: +33(0)4.42.85.99.29 . Fax: +33(0)4.42.85.99.66

2.B.6. Final steps

Remove the equipment providing access to the tail gear box (TGB). 

### CAUTION

### T.F.S. No. 00000442

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2008.01.04 

### 2.C. IDENTIFICATION

Record compliance with this ALERT SERVIC E BULLETIN in the helicopter documents.



### 2.D. OPERATING AND MAINTENANCE INSTRUCTIONS

In accordance with Maintenance Program 05.20.03.

### T.F.S. No. 00000442

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2008.01.04 Figure 1 

### Area 1

### T.F.S. No. 00000442

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2008.01.04 Figure 2 

### Area 1

### T.F.S. No. 00000442

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2008.01.04 

### 3. MATERIAL INFORMATION

3.A. MATERIAL: COST – AVAILABILITY

3.A.1. Cost

For any information concerning kits and / or comp onents, contact the Sales and Customer Relations Department of the EUROCOPTER Network.

3.A.2. Availability

Not applicable.



### 3.B. INFORMATION CONCERNING INDUSTRIAL SUPPORT

Not applicable.



### 3.C. MATERIAL REQUIRED FOR EACH HELICOPTER / ENGINE / COMPONENT

3.C.1. Kit(s) or component(s) to be or dered for one helicopter or one assembly

Material P/N Qty Item Key Word Former P/N Instructions

332A36 3063 20 AR 1 TGB attachment bolt

AR 2 Additional washer See § 2.A

3.C.2. Items to be ordered separately

Material P/N Qty Item Key Word

EN3628-080 AR 0.8 mm diameter lockwire

The products required for compliance with the Tasks and / or Work Cards listed in paragraph 1.K., can be ordered from the INTERTURBINE company.

Website: http://www.itlogistics.de Telephone: +49.41.91.809.300

AOG: +49.41.91.809.444

### T.F.S. No. 00000442

Approved under EASA DOA No. 21J.056 Page 12/12

2008.01.04 

### 3.D. PROCUREMENT CONDITIONS

Order the required quantity (unless otherwise specified)

from

EUROCOPTER Etablissement de Marignane

Direction Ventes et Relation Client

ECR

13725 MARIGNANE CEDEX

FRANCE



### NOTE 1

For ALERT SERVICE BULLETINS, order by:

Telex: HELICOP 410 969F Fax: +33 (0)4 42 85 99 96



### NOTE 2

On the purchase order, please specify the mode of transport, the

destination and the serial num bers of the helicopters to be

modified.



### 4. APPENDIX

Not applicable.