ASB EC135-63A-017

Revison 0, 2010-10-11 PAGE 1 of 11

Valid for Version(s): T1, T2, T2+, P1, P2, P2+

635 T1, 635 T2+, 635 P2+

ALERT SERVICE BULLETIN

SUBJECT: MAIN ROTOR DRIVE – Main Transmission

Retrofit of a corrugated washer in the filter housing

Revision number Issue date

Revision 0 20101011

Summary:

On some of the housing upper parts for the main transmission FS108 which are manufactured by ZFL

an inspection has shown that the bypass inlet in the oil filter area has not been worked i.a.w. the design

document. With this Alert Service Bulletin an equivalent structural design is established for the oil

supply to the bypass by installing a corrugated washer.

Compliance:

Compliance with this Alert Service Bulletin is prescribed. See Section 1.E.1 and 1.E.2.

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ASB EC135-63A-017

PAGE 2 of 11 Revison 0, 2010-10-11

1. PLANNING INFORMATION

1.A. EFFECTIVITY

1.A.1. Helicopters/installed equipment

EC135/EC635, all models with housing upper part P/N 4649 301 034 (for affected S/N see

Table 1 on page 9 and 10) of the main transmission.

NOTE The S/N of the housing upper part is given in the log card of the main

transmission and on the housing upper part (see Figure 1).

1.A.2. Non–installed equipment

See Section 1.A.1.

1.B. ASSOCIATED REQUIREMENTS

Not applicable.

1.C. REASON

On some of the housing upper parts for the main transmission FS108 which are manufactured

by ZFL an inspection has shown that the bypass inlet in the oil filter area has not been worked

i.a.w. the design document. With this Alert Service Bulletin an equivalent structural design is

established for the oil supply to the bypass by installing a corrugated washer. In the course of the

next repair or a major overhaul measure for the main transmission but no later than 4000 fh after

receipt of this Alert Service Bulletin the filter housing is reworked. The corrugated washer will be

deleted then.

1.D. DESCRIPTION

Remove the oil filter element. Install the corrugated washer. Install the oil filter element.

1.E. COMPLIANCE

1.E.1. Compliance at the works

Helicopters/installed equipment:

(a) The retrofit of the corrugated washer in the filter housing of the housing upper part of the

main transmission must be accomplished no later than by December 31, 2010 i.a.w.

Section 3.B.2.(a) of this Alert Service Bulletin.

(b) The retrofit of an affected housing upper part must be accomplished within the framework

of the next major repair or a major overhaul measure for the main transmission, but no later

than 4000 fh after receipt of this Alert Service Bulletin from the manufacturer or from an

service station authorized by the manufacturer i.a.w. Section 3.B.2.(b).

Non–installed equipment:

(c) The retrofit of the corrugated washer in the filter housing of the housing upper part of the

main transmission must be accomplished no later than by December 31, 2010 i.a.w.

Section 3.B.2.(a) of this Alert Service Bulletin.

(d) The retrofit of an affected housing upper part must be accomplished within the framework

of the next major repair or a major overhaul measure for the main transmission, but no later

than 4000 fh after receipt of this Alert Service Bulletin from the manufacturer or from an

service station authorized by the manufacturer i.a.w. Section 3.B.2.(b).

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ASB EC135-63A-017

Revison 0, 2010-10-11 PAGE 3 of 11

1.E.2. Compliance in service

Helicopters/installed equipment:

See Section 1.E.1.

Non–installed equipment:

See Section 1.E.1.

1.F. APPROVAL

Approval of this document:

The technical content of this document is approved under the authority of

DOA No. EASA.21J.034.

1.G. MANPOWER

Qualification Mechanic Electrician Pilot Others

Time approx. 5 h − − −

1.H. WEIGHT AND BALANCE

Not applicable.

1.I. EFFECT ON ELECTRICAL LOADS

Not applicable.

1.J. SOFTWARE MODIFICATION EMBODIMENT RECORD

Not applicable.

1.K. REFERENCES

AMM EC135 and AMM EC135/635.

1.L. OTHER DOCUMENTS AFFECTED

Not applicable.

1.M.INTERCHANGEABILITY OR MIXABILITY OF PARTS

Interchangeability:

Not applicable.

Mixability:

Not applicable.

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ASB EC135-63A-017

PAGE 4 of 11 Revison 0, 2010-10-11

2. MATERIAL INFORMATION

2.A. MATERIAL: PRICE – AVAILABILITY – PROCUREMENT

Copy reply form sheet on page 11, fill out and return to ECD.

After receipt and evaluation of the completed reply form sheet retrofit kit SB-135-63A-017-2C will

be delivered free of cost.

2.B. INFORMATION CONCERNING INDUSTRIAL SUPPORT

Not applicable.

2.C. MATERIAL REQUIRED FOR EACH HELICOPTER/COMPONENT

Kits or components to be ordered for one helicopter or one assembly:

Retrofit kit SB-135-63A-017-2C

No. Keyword Qty New P/N Old P/N Disposition

1 corrugated

washer 1 0630100377 − −

2 Oring 1 0634313445 0634313445 −

3 Oring 1 0634313198 0634313198 −

Consumable material to be ordered separately:

Consumable materials must be separately ordered at the INTERTURBINE AVIATION

LOGISTICS company. The given CM numbers are i.a.w. the AMM List of Consumable Materials.

Website: http://www.interturbine.com

Tel.: +49.41.91.809.300

AOG: +49.41.91.809.444.

No. Keyword Qty Material part number CM Disposition

1 Lubricating oil a.n.* MILPRF23699 or

O156 (NATO) or

CMS N49999X0040 or

DERD 2499

103 A, B

2 Lubricating oil a.n.* ZFNL3001 1001 A, B

3 Dry cleaning solvent a.n.* MILPRF680 or

TL68100012/1a or

S752 (NATO)

202 A

*a.n. = as needed

Disposition:

A = Required to wet the O-rings when the oil filter element is installed i.a.w. 

AMM, 63-21-00, 4-5.

B = Choose the lubricating oil given in No. 1 and 2 corresponding to the transmission oil 

used.

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ASB EC135-63A-017

Revison 0, 2010-10-11 PAGE 5 of 11

3. ACCOMPLISHMENT INSTRUCTIONS

3.A. GENERAL INFORMATION

Not applicable.

3.B. OPERATIONAL PROCEDURE

3.B.1. Preliminary steps

Copy reply form sheet on page 11, fill out and return to ECD.

3.B.2. Procedure

(a) Retrofit of the corrugated washer:

1 Remove LH and RH gear fairings i.a.w. AMM, 71-11-00, 4-4.

2 Remove oil filter element i.a.w. AMM, 63-21-00, 4-5.

3 Install the corrugated washer (7, Figure 2) in the middle of the filter housing (8) of the

housing upper part of the main transmission (see also Figure 3).

4 Install oil filter element i.a.w. AMM, 63-21-00, 4-5.

5 Install LH and RH transmission fairings i.a.w. AMM, 71-11-00, 4-4.

6 Enter the following in the log card of the main transmission: ”ASB EC135-63A-017

accomplished. Housing upper part of the main transmission must be reworked at the

next major repair or major overhaul measure for the main transmission, but no later

than 4000 fh after receipt of this Alert Service Bulletin”.

(b) Rework of the housing upper part by a service station authorized by the manufacturer:

NOTE With accomplishment of this rework corrugated washer 0630100377 is

deleted.

1 Rework housing upper part i.a.w. Service Instruction EC135FS108-1659-1009 by ZFL.

2 Confirm accomplishment of this rework by an entry in the log card of the main

transmission.

3.B.3. Final steps

Not applicable.

3.C. IDENTIFICATION

Not applicable.

3.D. OPERATING AND MAINTENANCE INSTRUCTIONS

Flight manual:

Not applicable.

AMM/maintenance manual:

Not applicable.

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ASB EC135-63A-017

PAGE 6 of 11 Revison 0, 2010-10-11

S/N Position of the Housing Upper Part

Figure 1

Housing upper part

S/N of the housing upper part

Main transmission shown when removed.

It is not required to remove the main transmission and the main transmission drive in order

to identify the S/N of the housing upper part.

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ASB EC135-63A-017

Revison 0, 2010-10-11 PAGE 7 of 11

Housing Upper Part – Installation of corrugated washer

Figure 2

1 Screw

2 Washer

3 Filter cover

4 O-ring 0634313445

5 O-ring 0634313198

6 Oil filter element

7 Corrugated washer 0630100377

8 Filter housing

9 Housing upper part

1X3

2X3

3

4

5

6

7

8

9

Install corrugated washer in the middle of the filter housing.

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ASB EC135-63A-017

PAGE 8 of 11 Revison 0, 2010-10-11

Housing Upper Part – Installation of corrugated washer

Figure 3

1 Corrugated washer 0630100377

2 Filter housing

2

1

Install corrugated washer in the middle of the filter housing.

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ASB EC135-63A-017

Revison 0, 2010-10-11 PAGE 9 of 11

S/N of the affected housing upper parts:

Page 1 of 2

Table 1

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ASB EC135-63A-017

PAGE 10 of 11 Revison 0, 2010-10-11

S/N of the affected housing upper parts:

Page 2 of 2

Table 1

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ASB EC135-63A-017

Revison 0, 2010-10-11 PAGE 11 of 11

Helicopter S/N:

Please copy page! Original page remains in ASB!

To:

Eurocopter Deutschland GmbH,

Mr Maynard David (Customer Logistic Manager)

Fax: +0049 (0)906-714081

e-mail: david.maynard@eurocopter.com

In order to be able to quickly accomplish this Alert Service Bulletin it is necessary to return

the completed reply form sheet to ECD.

The required retrofit kit SB-135-63A-017-2C can only be delivered after receipt and

evaluation of the completed reply form sheet. Thank you!

Reply form sheet

Operating time of the helicopter:

Planned retrofit of the corrugated washer:

Housing upper part S/N:

Operating time of the main transmission

since last TBO:

Main transmission S/N:

Date: Signature:

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

ASB EC135-63A-017

Revison 0, 2010-10-11 PAGE 11 of 11

Helicopter S/N:

Please copy page! Original page remains in ASB!

To:

Eurocopter Deutschland GmbH,

Mr Maynard David (Customer Logistic Manager)

Fax: +0049 (0)906-714081

e-mail: david.maynard@eurocopter.com

In order to be able to quickly accomplish this Alert Service Bulletin it is necessary to return

the completed reply form sheet to ECD.

The required retrofit kit SB-135-63A-017-2C can only be delivered after receipt and

evaluation of the completed reply form sheet. Thank you!

Reply form sheet

Operating time of the helicopter:

Planned retrofit of the corrugated washer:

Housing upper part S/N:

Operating time of the main transmission

since last TBO:

Main transmission S/N:

Date: Signature:

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