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 CEDEX FRANCE

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 SERVICE BULLETIN form the subject of DGAC 

Airworthiness Directive No. F-2007-027. 

Revision 1 of this ALERT SERVICE BULLETIN gives 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 SERVICE BULLETIN does not affect compliance with 

Revision 0. 

1.D. DESCRIPTION 

During a scheduled maintenance check (750-hour inspection), interference was discovered between 

the end of the threaded section of the TGB aft 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 tightening 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 the 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 finally lead to the loss of the TGB, 

EUROCOPTER renders compliance with the instructions given in this ALERT SERVICE BULLETIN 

mandatory until these actions are taken. 

1.E. COMPLIANCE 

EUROCOPTER renders compliance with this 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 within 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 within 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 helicopters 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 Organisation Approval No. 21J.056. 

The technical information contained in revision 1 of this ALERT SERVICE BULLETIN was approved 

on January 04, 2008 under the authority of EASA Design Organisation Approval N°21 J.056. 

1.G. MANPOWER 

Qualification: Mechanic or aircraft 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) Tasks: 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 soon be incorporated in the documentation. 

In the following procedure, the additional washer (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 Øi= 12.5 mm, tolerance H14, 

Its outside diameter must be Øe= 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 providing 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 than 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: (Blind 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 64-20-00-421 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 64-20-00-421 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 section 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 attachment 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 Customer 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 

Approved under EASA DOA No. 21J.056 Page 8/12 

2008.01.04 

2.C. IDENTIFICATION 

Record compliance with this ALERT SERVICE BULLETIN in the helicopter documents. 

2.D. OPERATING AND MAINTENANCE INSTRUCTIONS 

In accordance with Maintenance Program 05.20.03. 
T.F.S. No. 00000442 

Approved under EASA DOA No. 21J.056 Page 9/12 

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 components, 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 ordered 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 numbers of the helicopters to be 

modified. 

4. APPENDIX 

 

Not applicable.