## BOLLETTINO TECNICO N° 

# 13 9-306

The technical content of this document is approved under the authority of DOA nr. EASA.21J.005 DATE Dec em ber 12, 2012 REV. /

Compliance with this Bulletin is:

An appropriate entry should be made in the aircraft log book upon accomplishment. If ownership of aircraft has changed, please, forward to new owner. Page 1 of 6 SUBJECT: NOSE LANDING GEAR, INSPECTION OF ARMS PIN INSTALLATION.

REASON: to check the correct installation of Nose Landing Gear (NLG) pins P/N 1661-0001.

HELICOPTERS AFFECTED: all the following AB139/AW139 helicopters equipped with NLG assy P/N 3G3220V00133 or P/N 3G3220V00135:  from S/N 31005 to S/N 31157 (except S/N 31007);  from S/N 31201 to S/N 31398;  from S/N 31400 to S/N 31440 (except S/N 31413, S/N 31415, S/N 31417, S/N 31420, S/N 31422 thru S/N 31424, S/N 31427, S/N 31429 thru S/N 31431 , S/N 31433, S/N 31434 and S/N 31439).  from S/N 41001 to S/N 41023;  from S/N 41201 to S/N 41293 (except S/N 41276, S/N 41287, S/N 41289, S/N 41290, S/N 41291 and S/N 41292);  fro m S/N 41300 to 41310 (except S/N 41302, S/N 41304, S/N 41305, S/N 41306, S/N 41309).

## B.T. 13 9- 306

Page 2 of 6 COMPLIANCE: within fifty (50) flight hours or one (1) month from receipt of this Bollettino, whichever comes first.

DESCRIPTION: events of incorrect pin installations have been verified on some aircrafts in service, causing a prestress condition on the pin flange. This Bollettino provides the instruction to perform a one-off visual inspection to confirm correct pin installation.

REQUIRED MANPOWER: to comply with this Bollettino Tecnico one (1) Maintenance-Man-Hour (MMH) is deemed necessary: Man-hours are based on hands-on time and can change with personnel and facilities available.

WARRANTY : N.A.

REQUIRED MATERIALS: the following consumable materials are necessary to accomplish this Bollettino: SPEC./AW Code Number DESCRIPTION Q. ty NOTE S Commercial Ardrox AV15, Corrosion Inhibiting Compound (C343) AR Local supply

Refer to A ir craft Material Data Information (AMDI) and Illustrated Parts Data (IPD) for the materials and consumable materials required to comply with the Data Modules referenced in this Bollettino Tecnico.

## B.T. 13 9- 306

Page 3 of 6 SPECIAL TOOLS: the following special tools are required to accomplish this Bollettino: P/N DESCRIPTION Q. ty REMARKS 3G0705G00231 or approved alternative Jack, hydraulic (HA

- 01

- 00) 4 Local supply
Refer to Illustrated Tools and Equipment Publication (ITEP) for other special tools required to comply with the AMP Data Modules referenced in this Bollettino Tecnico.

WEIGHT AND BALANCE CHANGES: N.A.

REFERENCES:  AW139 Aircraft Corrosion Control Publication (ACCP)  AW139 Aircraft Material Data Information (AMDI)  AW139 Aircraft Maintenance Publication (AMP)  AW139 Illustrated Tools and Equipment Publication (ITEP)

PUBLICATIONS AFFECTED:  AW139 Aircraft Maintenance Publication (AMP)

COMPLIANCE INSTRUCTIONS: 1. Prepare the helicopter on ground for a safe maintenance. Disconnect the battery, all electrical power sources and/or the external power supply. Refer to AMP, see DM n° 39 -A- 00

- 20

- 00

- 00A -120A- A. NOTE

Step 2 and step 7 are applicable only to helicopters equipped with Kit NLG doors P/N 3G5280F00111, P/N 4G5280F00111 or P/N 4G5280F00112. 2. Open NLG doors, as necessary, to get access to the pins installation (1) on NLG arms. Refer to AMP, see DM n° 39-A- 52

- 81

- 00 -00A-540A- K.

## B.T. 13 9- 306

Page 4 of 6 3. Do a visual inspection of the pin installations (1) on both left and right arms as follows: 3.1 Check for the proper installation of the following hardware:  bolt (2);  washer (3), under bolt head;  washer (4), between NLG arm and pin (5);  pin (5);  washer (6), under nut;  nut (7);  cotter pin (8). 3.2 Make sure that the washer (4) is correctly installed as shown in detail A. 3.3 If washer installation is compliant with detail A, go to step 5 , otherwise perform following step 4. 4. If on one or both sides the washer (4) P/N NAS1149C0563R is not present or the installation is different from the one prescribed in detail A, do as follows: 4.1 Lift the helicopter on jacks. Refer to AMP, see DM n° 39-A- 07

- 11

- 00 -00A000A

- A. 4.2 Remove cotter pin (8), nut (7), washer (6), bolt (2), washer (3), pin (5) and washer (4) , if present . Discard the cotter pin (8). 4.3 Do a visual inspection of the bolt (2) and the nut (7) for corrosion. If you find signs of corrosion, replace them installing pin (5) at steps 4.6 a nd 4.7

. 4.4 Do a visual inspection of the pin (5) for corrosion and condition. If you find signs of corrosion and/or damage do as follows: CAUTION Make sure not to damage the surface of the pin, removing corrosion and/or damage at following step 4.4 .1

. 4.4.1 Remove the light corrosion and/or damage with an abrasive stone or glass fibre brush. Refer to ACCP, DM n° 39 -A- 20

- 40

- 00

- 00A -010A- E. 4.4.2 Measure the pin diameter after corrosion and/or damage removal. 4.4.3 Discard the pin if the diameter measured at step 4.4.2 is less than 25.359 mm (0.9984 in) and replace it with a new one at steps 4.6 and 4.7.

## B.T. 13 9- 306

Page 5 of 6 4.5 Do a visual inspection of the pin (5) for cracks as follows: 4.5.1 Do a visual inspection of the pin (5) for cracks. If you find any cracks, go to steps 4.6 and 4.7 to replace the pin (5). 4.5.2 Do a detailed inspection for surface cracks on the pin (5) flange using dye penetrant. Refer to AMP, see DM n° 39-A- 60

- 40

- 00 -01A-351A-D. If you find any cracks, replace the pin (5) following the steps 4.6 and 4.7. 4.6 Apply one coat of Ardrox AV15 Corrosion Inhibiting Compound (C343) on the pin (5), the bolt (2) and the nut (7). 4.7 Reinstall the pin (5) referring to the applicable steps of AMP DM n° 39-A- 32

- 21

- 01 -00A-720A- A. 4.8 Repeat steps 4.2 thru 4.7 on the other side if the washer (4) was not present or the installation is different from the one prescribed in detail A. 4.9 Lower the helicopter on the ground. Refer to AMP, see DM n° 39-A- 07

- 11

- 00 -00A-000A- A. 4.10 Skip steps 5 and 6 and go to step 7. CAUTION Do not remove the bolt (2) to perform the visual inspection at step 5. 5. Do a visual inspection of the bolt (2) head and the nut (7) for corrosion (bolt removal is not required) . If you find signs of corrosion, do as follows: 5.1 Lift the helicopter on jacks. Refer to AMP, see DM n° 39

- A

- 07

- 11

- 00

- 00A

00 0A

- A. 5.2 Replace the defective item referring to the applicable steps of AMP DM n° 39

- A

- 32

- 21

- 01

- 00A

- 720A

- A. 5.3 Lower the helicopter on the ground. Refer to AMP, see DM n° 39

- A

- 07

- 11

- 00

- 00A

- 000A

- A. 6. Apply one coat of Ardrox AV15 Corrosion Inhibiting Compound (C34 3) on the bolt (2) head and the nut (7).
7. Close NLG doors opened at step 2 . Refer to AMP, see DM n° 39

- A

- 52

- 81

- 00

- 00A

740A

- K

. 8. Return helicopter to flight configuration and r ecord for compliance with this Bollettino on the helicopter logbook.

## B.T. 13 9- 306

Page 6 of 6 Figure 1Note: Remarks:

Informazioni: Information: Al fine di gestire le varianti alla configur azione base, in relazione all’emissione de l Bollettino Tecnico, preghiamo di voler compilare il presente modulo in tutte le sue parti e sped irlo all’indirizzo sopra indicato. Si ring razia 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: 

### AGUSTA **WESTLAND S.p.A.**  CUSTOMER SUPPORT & SERVICES - ITALY PRODUCT SUPPORT ENGINEERING DPT. Via del Gregge, 100 2101 5 Lonate Pozzolo (VA) - I T ALY T el

. : +39 0331 664905 Fa x : +39 0331 66468 4 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.