BOLLETTINO TECNICO N° 139-392

The technical content of this document is approved 

under the authority of DOA nr. EASA.21J.005 

DATE September 23, 2014

REV. /

Compliance with

this bulletin is: 

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SUBJECT 

LOWER HALF SCISSOR SPECIAL NUT P/N 3G6230A06851 

REASON 

Introduce an interim inspection and a special nut for containment. 

HELICOPTERS AFFECTED 

Part I: all AB139/AW139 helicopters installing MR Rotating Scissors P/N 

3G6230A00733.

Part II: all AB139/AW139 helicopters installing MR Rotating Scissors P/N 

3G6230A00733 and not installing special nut P/N 3G6230A06851.

COMPLIANCE 

Part I: on helicopters not installing special nut P/N 3G6230A06851

within five (5) flight hours or one (1) week from receipt of this Bollettino Tecnico, 

whichever comes first, then daily, up to accomplishment of Part II, and then 

every twenty-five (25) flight hours after accomplishment of Part II. 

on helicopters already installing special nut P/N 3G6230A06851

every twenty-five (25) flight hours from receipt of this Bollettino Tecnico 

AgustaWestland S.p.A

Via Giovanni Agusta, 520

21017 Cascina Costa di Samarate (VA) Italy

Tel.: +39 0331 229111 - Fax: +39 0331 229605/222595

MANDATORY

An appropriate entry should be made in the aircraft log book upon accomplishment.

If ownership of aircraft has changed, please, forward to new owner.

ALERT

ALERT
B.T. 139-392

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Part II: within one hundred (100) flight hours or one (1) month from receipt of this 

Bollettino Tecnico whichever comes first.

DESCRIPTION

This Bollettino Tecnico introduces a special nut as a containing element in case of lower 

scissor bearing dislodging providing additional safety to the installation. This represents 

a further follow-up action in addition to those already fielded to address the early failures 

in service due to a quality issue with the lower scissor spherical bearing liner. An interim 

inspection program is also introduced to monitor the behavior of the spherical bearings in 

service.

REQUIRED MANPOWER

It is estimated that, in order to accomplish this Bollettino Tecnico, the following 

maintenance man-hours (MMH) are necessary:

Part I: one (1) MMH;

Part II: one (1) MMH.

Man-hours are based on hands-on time and may vary with personnel and facilities 

available.

WARRANTY

 Within the calendar terms mentioned at point “Compliance”, the parts required to 

apply the present Bollettino shall be supplied on a free of charge basis by 

AgustaWestland upon Customers request, except for consumable materials and 

special tools.

 Upon application of this Bollettino, Customers are requested to submit to 

AgustaWestland Warranty Administration the relevant W.M.M. (Warranty 

Claim/Maintenance Work Order/Malfunction Report).
B.T. 139-392

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REQUIRED MATERIALS

The following materials, necessary to accomplish Part II of this Bollettino Tecnico, can 

be requested to AgustaWestland:

P/N DESCRIPTION Q.TY Note

3G6230A06851 Special nut 2

NAS1149C0863R Washer, flat 2

MS24665-302 Pin, cotter 2

Moreover the following consumable materials, or equivalent, are necessary to comply 

with Part II of this Bollettino Tecnico:

Spec./AW code number DESCRIPTION Q.TY Note

MIL-PRF-16173E INT AMD 

1, grade 2

cod. 999999999000000191

Corrosion inhibitor (C002) AR Local supply

Refer to AMDI for the consumable materials necessary to comply with the AMP data 

modules referenced in this Bollettino Tecnico.

SPECIAL TOOLS

The following special tools are necessary to accomplish this Bollettino Tecnico:

P/N DESCRIPTION Q.TY NOTES

RMGE-DS-06-2010-LH or

an approved alternative

Platform (GG-01-00)

AR (1)

RMGE-DS-06-2010-RH or

an approved alternative

Platform (GG-02-00)

Local supply Magnifying glass AR (2)

Local supply Hand torch AR (2)

3G6205G26631 Wrench, special nut 

removal/installation

AR (3)
B.T. 139-392

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Notes:

(1) Refer to Illustrated Tools and Equipment Publication (ITEP) for this special tool and 

also for other special tools required to comply with the AMP data modules 

referenced in this Bollettino Tecnico.

(2) Required to comply only with Part I of this Bollettino Tecnico.

(3) Required to comply only with Part II of this Bollettino Tecnico.

WEIGHT AND BALANCE CHANGES

N.A.

REFERENCES

 AW139 Aircraft Maintenance Data Information (AMDI)

 AW139 Aircraft Maintenance Publication (AMP)

 AW139 Illustrated Tools and Equipment Publication (ITEP)

PUBLICATIONS AFFECTED

 AW139 Aircraft Maintenance Publication (AMP)

 AW139 Illustrated Parts Data (IPD)

 AW139 Illustrated Tools and Equipment Publication (ITEP)
B.T. 139-392

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COMPLIANCE INSTRUCTIONS

Part I

1. Prepare the helicopter for a safe ground maintenance. Disconnect the battery and all 

the electrical power sources and/or the external power supply. Refer to AMP, see 

DM n° 39-A-00-20-00-00A-120A-A.

2. Put the platforms (GG-01-00) and (GG-02-00), or approved alternatives, adjacent to 

the left and to the right side of the fuselage, respectively.

3. Open access door 473AL. Refer to AMP, see DM n° 39-A-06-41-00-00A-010A-A.

4. With reference to Figure 1, get access to the MR area and perform a general visual 

inspection of the MR rotating scissors P/N 3G6230A00733, using a magnifying glass 

and a hand torch, paying particular attention to the spherical bearings. If you find 

damages (a typical damage is shown in figures 4 thru 8), contact AW139 Product 

Support Engineering (aw139.mbx@agustawestland.com).

5. With reference to Figure 1, perform an operational check for play and wear of the 

lower half scissors spherical bearing P/N 3G6230V00654 (refer to section A-A), 

paying particular attention to the bearing staking condition; to do this, manually move 

the lower half scissor along the axis of the spherical bearing.

5.1. If no unusual play and/or wear is detected, no further action is required. Go to 

step 6.

5.2. If unusual play and/or wear is detected, perform a detailed inspection for 

condition, damage and play of the MR rotating scissors according to steps 9 

through 12.9 of AMP DM n° 39-C-62-31-00-00A-286C-A.

5.2.1. If play is within limits, no further action is required. Go to step 6.

5.2.2. If play is beyond limits or wear is detected, report findings to AW139 

Product Support Engineering (aw139.mbx@agustawestland.com).

6. Close access door 473AL. Refer to AMP, see DM n° 39-A-06-41-00-00A-010A-A.

7. Remove the platforms from left and right sides of the fuselage.
B.T. 139-392

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8. Return the helicopter to flight configuration and record for compliance with Part I of 

this Bollettino Tecnico on the helicopter logbook.

Part II

1. Prepare the helicopter for a safe ground maintenance. Disconnect the battery and all 

the electrical power sources and/or the external power supply. Refer to AMP, see 

DM n° 39-A-00-20-00-00A-120A-A.

2. Put the platform (GG-01-00), or an approved alternative, adjacent to the left side of 

the fuselage.

3. Open access door 473AL. Refer to AMP, see DM n° 39-A-06-41-00-00A-010A-A.

4. With reference to figure 2, get access to the MR rotating scissors area.

5. With reference to figure 3, replace the lower half scissor existing nut as follows:

5.1. Remove and discard the cotter pin P/N MS24665-302.

5.2. Remove and discard the nut P/N MS17825-8.

5.3. Remove from the scissor retaining bolt the lower half scissor, washers P/N 

NAS1149C0832R and scissor washer P/N 3G6230A04552. Retain scissor 

washer P/N 3G6230A04552 for re-use.

WARNING

THIS INSTALLATION INCLUDES VITAL POINTS 

(VP). YOU MUST OBEY THE LOCAL 

REGULATIONS APPLICABLE TO THE VITAL 

POINTS.

CAUTION

Make sure that the chamfered side of the scissor 

washer P/N 3G6230A04552 points to the spherical 

bearing in the lower half scissor.

5.4. Install the lower half scissor on the scissor retaining bolt using new washer P/N 

NAS1149C0863R and scissor washer P/N 3G6230A04552.
B.T. 139-392

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5.5. Install the new special nut P/N 3G6230A06851.

5.6. Apply the wrench P/N 3G6205G26631 to the special nut.

5.7. Torque the special nut to 61.0 thru 73.2 N m (539.9 thru 647.9 lbf in) with the 

wrench P/N 3G6205G26631.

5.8. Secure the special nut to the retaining bolt with a new cotter pin P/N MS24665-

302.

5.9. Apply the corrosion inhibitor (C002) to the cotter pin and the special nut.

6. Repeat step 5 to replace the other lower half scissor nut.

7. Close the access door 473AL. Refer to AMP, see DM n° 39-A-06-41-00-00A-010AA.

8. Remove the platform from the left side of the fuselage.

9. Return helicopter to flight configuration and record for compliance with Part II of this 

Bollettino Tecnico on the helicopter logbook.
B.T. 139-392

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Figure 1
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Figure 2
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Figure 3
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Figure 4
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Figure 5
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Figure 6

Figure 7
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Figure 8
Note: 

Remarks:

Informazioni: 

Information:

Al fine di gestire le varianti alla configurazione base, in relazione all’emissione del Bollettino Tecnico, preghiamo di voler compilare il presente modulo in tutte le sue parti e spedirlo all’indirizzo sopra indicato. Si ringrazia per la gentile collaborazione data. 

We request your cooperation in filling this form, in order to keep out statistical data relevant to aircraft configuration up-to-date. The form should be filled in all 

its parts and sent to the above address. We thank you beforehand for the information given.

MODULO APPLICAZIONE BOLLETTINO TECNICO

TECHNICAL BULLETIN COMPLIANCE FORM

Data: 

Date:

Numero: 

Number:

Revisione: 

Revision:

Prego spedire a questo indirizzo: 

Please send to the following address: 

AGUSTAWESTLAND S.p.A. 

CUSTOMER SUPPORT & SERVICES - ITALY

PRODUCT SUPPORT ENGINEERING DPT.

Via del Gregge, 100

21015 Lonate Pozzolo (VA) - ITALY 

Tel.: +39 0331 664905

Fax: +39 0331 664684

Telefono: 

Telephone:

Fax:

Data Applicazione B.T.: 

B.T. Compliance Date:

Denominazione Cliente ed Indirizzo: 

Customer Name and Address:

Modello Elicottero 

Helicopter Model S/N Matricola Tail Number

Ore Totali 

Total Hours

Ore D.U.R. 

T.S.O.