### ALERT SERVICE BULLETIN AS350

Approved under EASA DOA No. 21J.056. 

# 05.00.60 Page 1/9

2009.12.09

This document is available on t he internet: www.eur ocopter.com/techpub EUROCOPTER

DIRECTION TECHNIQUE SUPPORT

13725 MARIGNANE C EDEX F RANCE 

### CIVIL VERSION(S): B, BA, BB, D, B1, B2,

B3

MILITARY VERSION(S): L1



# ALERT SERVICE BULLETIN

No. 05.00.60

SUBJECT : TIME LIMITS - MAINTENANCE CHECKS

Check for no play in the tail rotor pitch-change links

ATA : 65

REVISION No. DATE OF APPROVAL DATE OF ISSUE

Revision 0 On: December 08, 2009 2009.12.09

### ALERT SERVICE BULLETIN AS350

Approved under EASA DOA No. 21J.056. 

# 05.00.60 Page 2/9

2009.12.09 CAUTION

THE INFORMATION AND INSTRUCTIONS CONTAINED IN

THIS ALERT SERVICE BU LLETIN ARE INTENDED FOR

MAINTENANCE PERSONNEL AND FLIGHT CREWS.



### 1. PLANNING INFORMATION

1.A. EFFECTIVITY

1.A.1. Helicopters/installed equipment

Helicopters equipped with tail rotor pitch-change links with part numbers:

350A33-2100-00, 350A33-2100-01, 350A33-2100-02, 350A33-2100-03, 350A33-2100-04, 350A33-2121-00,

350A33-2121-01, 350A33-2121-02, 350A33-2143- 00, 350A33-2145-00 and 350A33-2145-01.

1.A.2. Non-installed equipment

Not applicable.



### 1.B. ASSOCIATED REQUIREMENTS

Not applicable.



### 1.C. REASON

To make the periodicity of the check for no play in tail rotor pitch-change links mandatory by introducing it in

the Airworthiness Limitations Section (A LS) of the Maintenance Program (PRE).

This ALERT SERVICE BULLETIN will form the subject of an EASA-Airworthiness Directive.

### ALERT SERVICE BULLETIN AS350

Approved under EASA DOA No. 21J.056. 

# 05.00.60 Page 3/9

2009.12.09 1.D. DESCRIPTION

On an AS350, the pilot felt slight vibrations in the pedal unit in flight. A few minutes later, the vibration level

increased and the pilot carried out an autorotation.

After landing, it was discovered that one tail rotor pi tch-change link was deteriorated, that the tail-boom cone

was missing and there was an impact mark on the tail-boom.

Investigation of the pitch-change link has shown extensiv e wear on the ball-joint and failure of the web of the

ball-joint due to fatigue. The deterioration of t he pitch-change link concerned could have been discovered

during the check for no play in the links. Currently, this check is scheduled at the check after the last flight of

the day (ALF) without exceeding 30 flying hours.

Any undiscovered deterioration of a pitch-change link can in time lead to the loss of the anti-torque function.

EUROCOPTER therefore makes the periodicity of t he check for no play in tail rotor pitch-change links,

mandatory, in order to prevent any pitch-change link failure.

Furthermore, EUROCOPTER provides some detailed information concerning the existing procedure to

enable easier detection of play, if any.



### 1.E. COMPLIANCE

EUROCOPTER makes 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 service: By the operator

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

Comply with paragraph 2.B.1. within 30 flying hours fo llowing receipt of this ALERT SERVICE BULLETIN,

issued on the date indicated at the foot of the page.

Then,

Comply with paragraph 2.B.2. at in tervals not exceeding 30 flying hours.

1.E.2.b. On non-installed equipment

Not applicable.

### ALERT SERVICE BULLETIN AS350

Approved under EASA DOA No. 21J.056. 

# 05.00.60 Page 4/9

2009.12.09 1.F. APPROVAL

1.F.1. Approval of the modifications

Not applicable.

1.F.2. Approval of the Service Bulletin

The technical information contained in this ALERT SERVICE BULLETIN Revision 0 was approved

on December 08, 2009 under the authority of EASA Desi gn Organisation Approval No. 21J.056 for civil

version helicopters subject to an Airworthiness Certificate.

The technical information contained in this ALERT SERVICE BULLETIN Revision 0 was approved

on December 08, 2009 by the EUROCOPTER Airworthi ness Department for military version helicopters.



### 1.G. MANPOWER

1.G.1. Qualification

EUROCOPTER recommends that compliance with this ALERT SERVICE BULLETIN is ensured by qualified

personnel as follows:

Qualification: 1 Mechanical Engineering Technician.

or,

1 suitably trained pilot, qualified in accordance with the local regulation.

1.G.2. Time for the operations

The operation times are given for informati on purposes and for a standard configuration.

Time for the operations: Approximately 5 minutes.



### 1.H. WEIGHT AND BALANCE

Not applicable.



### 1.I. EFFECT ON ELECTRICAL LOADS

Not applicable.



### 1.J. SOFTWARE MODIFICATION EMBODIMENT RECORD

Not applicable.

### ALERT SERVICE BULLETIN AS350

Approved under EASA DOA No. 21J.056. 

# 05.00.60 Page 5/9

2009.12.09 1.K. REFERENCES

The documents required for compliance with this ALERT SERVICE BULLETIN are as follows:

MET: Work Card 65.20.00.601: Tail Gear-Box - Tail rotor pitch-change spider-Hub:

Condition check.

MET: Work Card 67.10.00.301: Rotor controls - General instructions.



### 1.L. OTHER DOCUMENTS AFFECTED

EUROCOPTER will modify the documents below in accordance with this ALERT SERVICE BULLETIN:

- Maintenance Program (PRE),

- Maintenance Manual (MET).

These documents will be issued subsequently.



### 1.M. TOOLING AFFECTED

Not applicable.



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

Not applicable.

### ALERT SERVICE BULLETIN AS350

Approved under EASA DOA No. 21J.056. 

# 05.00.60 Page 6/9

2009.12.09 

### 2. ACCOMPLISHMENT INSTRUCTIONS

2.A. GENERAL

- Read and comply with the general instruct ions as per MET Work Card 67.10.00.301.

- The operational procedure below is applicabl e to the two tail rotor pitch-change links.



### 2.B. OPERATIONAL PROCEDURE

2.B.1. Check for no play in the pitch-change links (Figure 1)

- Take the pitch-change link in your hand and position y our thumb on the yoke of the blade control horn (see

Detail B).

- Move the pitch-change link parallel to the centerline of the ball-joint in a manner enabling you to detect

play, if any.

Whilst moving the pitch-change link:

- With the other hand, move the blade in flapping direction (A), trying to find the position where axial play (if

any) in the ball-joint is detectable (s tress relieving in the pitch-change link).

. If you feel any play J comply with paragraph 2.B.3.

. If you feel no play J, leave as is.

2.B.2. Check at regular intervals and interpretation of the results

- If no play was felt during the previous check, comply with paragraph 2.B.1.

- If play was measured during the previous check, comply with paragraph 2.B.3.

2.B.3. Check of the ball-joints of the pitch-change links

- Check the ball-joint of the pitch-change link in accordance with MET Work Card 65.20.00.601

paragraph 4.2.1 “Pitch-change links”. Reco rd the measured play value.



### 2.C. IDENTIFICATION

Record initial compliance with this ALERT SER VICE BULLETIN on the he licopter documentation.



### 2.D. OPERATING AND MAINTENANCE INSTRUCTIONS

Not applicable.

### ALERT SERVICE BULLETIN AS350

Approved under EASA DOA No. 21J.056. 

# 05.00.60 Page 7/9

2009.12.09 Figure 1: Check for no play in the pitch-change links

### ALERT SERVICE BULLETIN AS350

Approved under EASA DOA No. 21J.056. 

# 05.00.60 Page 8/9

2009.12.09 

### 3. MATERIAL INFORMATION

3.A. MATERIAL: PRICE AND AVAILABILITY

3.A.1. Cost

For all information concerning the kits and/or com ponents, contact your usual sales representative.

3.A.2. Availability

The kits and/or components will be delivered on the operator’s order.



### 3.B. INFORMATION CONCERNING INDUSTRIAL SUPPORT

Not applicable.



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

3.C.1. Kits or components to be ordered for one helicopter or one assembly

Not applicable.

3.C.2. Products to be ordered separately

The materials identified by an asterisk "*" or required fo r 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

Phone: +49.41.91.809.300

AOG: +49.41.91.809.444.

### ALERT SERVICE BULLETIN AS350

Approved under EASA DOA No. 21J.056. 

# 05.00.60 Page 9/9

2009.12.09 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.