Leonardo ASB 139-609: Revision A

N° 1 39-609 DAT E: December 18, 2019 REV. : A - Ap ril 13, 2021 Pag e 1 of 28 TITLE ATA 63 - MGB BEARING LOCK-NUT REPLACEMENT

REVISION LOG The Revision A of this Service Bulletin supersedes the first issue dated December 18, 2019.

He licopters that have complied with previous issue of this Service Bulletin do not need any additional action.

Revision A is issued in order to add MGB P/N 3G6320A00136 S/N AW1, AW2, AW3, AW5, AW10 to Effectivity.

Revision bars identify changes.

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

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

Leonardo S.p.A.

Via Giovanni Agusta, 520 21017 Cascina Costa di Samarate (VA) Italy Tel.: +39 0331 229111 - Fax: +39 0331 229605/222595 ALERT

SERVICE BULLETIN

S.B. N°139-609 ALERT DATE: December 18, 2019 Page 2 of 28 REVISION: A - April 13, 2021

1. PLANNING INFORMATION A. EFFECTIVITY AB139/AW139 helicopters equipped with MGB P/N 3G6320A00131, P /N 3G6320A00132, P/N 3G6320A00133, P/N 3G6320A00134, P/N 3G6320A00135, P/N 3G6320A00136 (S/N AW1, AW2, AW3, AW5, AW10), P/N 4G6320A00132, P/N 4G6320A00133 or P/N 3G6320A22031 and NOT equipped with MGB bearing locknut P/N 3G6320A09152.

NOTE MGB without bearing lock-nut P/N recorded on the component Log Card are affected by this Service Bulletin.

B. COMPLIANCE  For MGB already compliant with Service Bulletin 139-567: within twenty eight thousand (28000) landings or at next overhaul, whichever occurs first, from the accomplishment date of Service Bulletin 139-567.

 For MGB having S/N listed in the following Table 1: within twenty eight thousand (28000) landings or at next overhaul, whichever occurs first, since 14 May 2018.

P/N S/N 3G6320A00133 M23 3G6320A00134 M6 P124 P129 P131 P162 P184 Q230 Q243 Q249 R272 V163 V21 V211 V241 V272 V281 V384 V386 V39 V622 V96 N76 N92 -

Table 1  For MGB having S/N not listed in the above Table 1 and having logged twenty six thousand (26000) landings or more from new: within two thousand (2000) landings or at next overhaul, whichever occurs first, from the original issue date of this Service Bulletin.

 For MGB having S/N not listed in the above Table 1 and having logged less than twenty six thousand (26000) landings from new: within two thousand (2000) landings

S.B. N°139-609 ALERT DATE: December 18, 2019 REVISION: A - April 13, 2021 Page 3 of 28 upon reaching twenty six thousand (26000) landings or at next overhaul, whichever occurs first.

NOTE If the number of landings applicable to each single MGB is not known throughout the entire service life of the MGB, the number of landings shall be calculated multiplying the MGB flight hours by a factor of six (6).

C. CONCURRENT REQUIREMENTS This Service Bulletin cancels and supersedes Service Bulletin 139-567 Rev. B.

D. REASON This Service Bulletin is issued to manage the one-off replacement of the MGB bearing l ock-nut P/N 3G6320A09151 with MGB bearing lock-nut P/N 3G6320A09152.

E. DESCRIPTION As a consequence of an in service issue reported during non-destructive testing of the st andard overhaul activity, LHD has reviewed MGB overhaul procedures introducing the replacement of MGB lock-nut P/N 3G6320A09151 and issued Service Bulletin 139-567 to prescribe the same one-off replacement in the operating fleet.

This Service Bulletin prescribes the introduction of the new MGB bearing lock-nut P/N 3G6320A09152.

The main difference between the existing nut P/N 3G6320A09151 and the new P/N 3G6320A09152 is related to the increase in the fillet radius between the cylindrical threaded part of the component and the flanged end; this allows reduction of the local peak stress in the critical areas of the nut which were found cracked in service. The new spherical bearing lock nut P/N 3G6320A09152 will be introduced on new built MGB and wi ll be in any case replaced on all MGBs at next Overhaul.

NOTE Replacement of existing MGB lock-nuts P/N 3G6320A09151 with P/N 3G6320A09151 is not allowed.

NOTE MGB lock-nut replacement procedure described in this Service Bulletin, has also been introduced in CR&OP

S.B. N°139-609 ALERT DATE: December 18, 2019 Page 4 of 28 REVISION: A - April 13, 2021 with IETP Issue 35.

NO TE MGB bearing lock-nut P/N 3G6320A09152 is fully interchangeable with MGB bearing lock-nut P/N 3G6320A09151, but the mixing of the current and new P/N on the same assembly is NOT allowed.

NOTE MGB lock-nut P/N 3G6320A09152 has been classified as Critical Part, having a Retirement Life introduced in AMPI Chapter 4 Issue 12.

F. APPROVAL The technical content of this Service Bulletin is approved under the authority of DOA nr.

E ASA.21.J.005. For helicopters registered under other Aviation Authorities, before applying the Service Bulletin, applicable Aviation Authority approval must be checked within Leonardo Helicopters customer portal.

EASA states mandatory compliance with inspections, modifications or technical directives and related time of compliance by means of relevant Airworthiness Directives.

If an aircraft listed in the effectivity embodies a modification or repair not LHD certified and affecting the content of this Service Bulletin, it is responsibility of the Owner/Operator to obtain a formal approval by Aviation Authority having jurisdiction on the aircraft, for any adaptation necessary before incorporation of the present Service Bulletin.

G. MANPOWER To comply with this Service Bulletin one hundred and ninety (190) MMH are deemed n ecessary.

MMH are based on hands-on time and can change with personnel and facilities available.

H. WEIGHT AND BALANCE N.A.

S.B. N°139-609 ALERT DATE: December 18, 2019 REVISION: A - April 13, 2021 Page 5 of 28 I. REFERENCES

1) PUBLICATIONS

DATA MODULE DESCRIPTION PART DM01 39-A-00-20-00-00A-120A-A Helicopter on ground for a safe maintenance.

- DM02 39-A-63-20-00-00A-520A-A Main gearbox group - Remove procedure - DM03 39-A-63-20-00-00A-720A-A Main gearbox group - Install procedure - DM04 39-A-71-11-07-00A-520A-A Forward sliding fairing - Remove procedure - DM05 39-A-71-11-07-00A-720A-A Forward sliding fairing - Install procedure - DM06 39-A-63-20-00-00A-364A-A Main gearbox group – leak check -

2) ACRONYMS AMDI Aircraft Material Data Information A MP Aircraft Maintenance Publication AMPI Air vehicle maintenance planning information CR&OP Component Repair and Overhaul Publication DM Data Module IETP Interactive Electronic Technical Publication ITEP Illustrated Tools and Equipment Publication LHD Leonardo Helicopter Division MGB Main Gearbox MMH Maintenance Man Hours

3) ANNEX Annex A MGB bearing lock-nut replacement J. PUBLICATIONS AFFECTED N.A.

K. SOFTWARE ACCOMPLISHMENT SUMMARY N.A.

S.B. N°139-609 ALERT DATE: December 18, 2019 Page 6 of 28 REVISION: A - April 13, 2021

2. MATERIAL INFORMATION A. REQUIRED MATERIALS

1) PARTS # P/N ALTERNATIVE P/N DESCRIPTION Q.TY LVL NOTE LOG P/N 1 A259A04-06 SCREW 2 (1) 139-609L1 2 MS21043-3 NUT 12 (1) 139-609L1 3 NAS1149C0332R WASHER 22 (1) 139-609L1 4 NAS1149D0332K WASHER 16 (1) 139-609L1 5 3G6320V00451 LIP SEAL 1 (1) 139-609L1 6 M83248/1-174 AS3209-174 PACKING 2 (1) 139-609L1 7 A866A55803W PACKING 2 (1) 139-609L1 8 NAS1149D0432K WASHER 10 (1) 139-609L1 9 NAS1149C0432R WASHER 10 (1) 139-609L1 10 MS21043-4 NUT 10 (1) 139-609L1 11 3G6320A09152 RING NUT 5 (1) 139-609L1 12 3G6320A05751 A871A0490B SPRING 5 (1) 139-609L1 13 3G6320A21131 RETAINING PLATE 5 (1) 139-609L1 14 MS21043-5 NUT 30 (1) 139-609L1 15 NAS1149C0532R WASHER 30 (1) 139-609L1 16 NAS1149D0532K WASHER 22 (1) 139-609L1 17 AS3209-014 PACKING 6 (1) 139-609L1 18 AS3209-018 PACKING 8 (1) 139-609L1 19 A259A05-08 SCREW 3 (1) 139-609L1 20 NAS1802-3-20 SCREW 10 (1) 139-609L1 21 AS3209-131 O-RING 3 (1) 139-609L1 22 AS3209-121 O-RING 2 (1) 139-609L1 23 AS3209-020 O-RING 2 (1) 139-609L1 24 AS3209-011 O-RING 1 (1) 139-609L1 25 M25988/1-028 O-RING 2 (1) 139-609L1 26 M83248/1-247 AS3209-247 O-RING 1 (1) 139-609L1 27 AS3209-013 PACKING 4 (1) 139-609L1 28 MS35266-62 MS9565-05 SCREW 4 (1) 139-609L1 29 AS3208-02 PACKING 4 (1) 139-609L1

2) CONSUMABLES T he following consumable materials, or equivalent, are necessary to accomplish this Service Bulletin:

# Spec./LHD code number DESCRIPTION Q.TY NOTE PART 30 Commercial Linth-free cloth (C011) AR (2) - 31 MIL-PRF-680, Type II Cleaning solvent (C010) Ardrox 5503A AR (2) - 32 MS20995C32 Safety wire (C014) AR (2) - 33 MIL-PRF-81322F Grease (C009) AR (2) - 34 ASTM D5363 Adhesive (C029) Loctite 222 AR (2) - 35 AWMS05-001 Type I class B grade 2 MC-780 B 2 (C355) AR (2) - 36 Commercial Cleaner (C023) Loctite quick clean 7031 AR (2) - 37 Commercial Parker “Super O-Lube” oil – Grease (C115) AR (2) - 38 Commercial Grease (C147) or SYN-TECH 3913-G1 AR (2) - 39 DOD-L-85734 Turbo Oil (C008) AR (2) - 40 MIL-S-46163, Type II grade N Loctite 242 AR (2) -

S.B. N°139-609 ALERT DATE: December 18, 2019 REVISION: A - April 13, 2021 Page 7 of 28 # Spec./LHD code number DESCRIPTION Q.TY NOTE PART 41 MIL-PRF-23699G Oil (C007) AR (2) - 42 DOD-PRF-85734 Oil (C366) AR (2) - 43 MIL-PRF-23699F Oil (C548) AR (2) - 44 MIL-PRF-85285 Type I High-Solids Paint, grey, n. 16440 (C380) AR (2) - 45 MIL-PRF-23377 Primer (C393) AR (2) - Refer also to AMDI for the consumable materials required to comply with the AMP DM referenced in the accomplishment instructions.

3) LOGISTIC MATRIX I n order to apply this Service Bulletin, the following Logistic P/N can be ordered in accordance with the applicable notes:

LOGISTIC P/N Q.TY (PER HELO) NOTE PART 139-609L1 1 (1) (3) - 3G6320A09152 5 (1) (4) - NOTE

(1) This item is required for MGB bearing lock-nut replacement procedure described in Annex A.

(2) Item to be procured as local supply.

(3) This item is NOT required for Customers who have already been provided with logistic P/N 139-567L1.

(4) This item is required only for Customers who have already been provided with logistic P/N 139-567L1.

B. SPECIAL TOOLS The following special tools, or equivalent, are necessary to accomplish this Service B ulletin:

# P/N DESCRIPTION Q.TY NOTE PART 46 3G6320A00231A188A Work trolley 1 (B1) - 47 3G6320A00231A029C Removal tool, lip seal 1 (B1) - 48 3G6320A00231A181C Lifting tool, mast-planetary assembly 1 (B1) - 49 3G6320A00231A029B Removal tool, roller bearing 1 (B1) - 50 3G6320A07231A188A Work trolley, mast-planetary assembly 1 (B1) (B2) - 51 3G6320A00231A029E Extractor 3 (B1) - 52 3G6320A07231A023D Reaction tool assembly 1 (B1) - 53 3G6320A00231A023G Tool, upper module lip seal installation 1 (B1) - 54 3G6320A00131A181A or 3G6305G00431 Lifting tool 1 (B1) - 55 3G6320A00231A023M Clamps 4 (B1) - 56 4F6320A00231A023B Clamps 3 (B1) - 57 3G6320A00231A029F Disassembly tool, planetary crown 1 (B1) - 58 3G6320A00131A029A Extractor tool, oil union 1 (B1) - 59 3G6320A00231A181B Lifting tool, upper module 4 (B1) - 60 3G6320A00231A023D Aligning pin 2 (B1) - 61 3G6320A00231A181A Lifting tool, ring gear 1 (B1) -

S.B. N°139-609 ALERT DATE: December 18, 2019 Page 8 of 28 REVISION: A - April 13, 2021 # P/N DESCRIPTION Q.TY NOTE PART 62 3G6320A00231A023C Bearing installation tool 1 (B1) - 63 3G0000X00533A182C Wooden support 1 (B1) - Refer also to ITEP for the special tools required to comply with the AMP DM referenced in the accomplishment instructions.

SPECIAL TOOLS NOTE This item is required for MGB bearing lock-nut replacement procedure described in Annex A.

This tool may be assembled using P/N 3G6320A07235A026A, P/N MN3-00155 and P/N MN3-00138.

C. INDUSTRY SUPPORT INFORMATION WARRANTY: Owners/Operators who comply with the instructions of this Service B ulletin no later than the applicable date in the “Compliance” section will be eligible to receive REQUIRED MATERIALS on free of charge basis, except for Consumable Materials and Special Tools.

NOTE: Customers who fail to comply with the instructions in this Service Bulletin before the compliance date are not eligible for the aforementioned special policy.

NOTE: Customers who have already been provided with MGB bearing lock-nuts P/N 3G6320A09151 shall return these to LHD in order to receive the superseding P/N 3G6320A09152 on a free of charge basis. Contact dedicated Spares Orders administrator to arrange parts exchange.

Please Issue relevant MMIR form to your Warranty Administration Dpt.

NOTE: Please contact LHD order administration in advance from the scheduled Service Bulletin application to request the tools supplying on loan. As soon as the present Service Bulletin is implemented, the tools supplied on loan must be promptly returned to LHD.

S.B. N°139-609 ALERT DATE: December 18, 2019 REVISION: A - April 13, 2021 Page 9 of 28

3. ACCOMPLISHMENT INSTRUCTIONS NOTE Customer is requested to contact the usual Customer Support & Service Management focal point in advance from the Service Bulletin scheduled application, to request the materials and special tools and to plan the MGB bearing lock-nut replacement as described in Annex A.

GENERAL NOTES

a) Place an identification tag on all components that are re-usable, including the attaching hardware that has been removed to gain access to the modification area and adequately protect them until their later reuse.

b) Protect properly all those equipment not removed from area affected by the modification during installation procedure.

1. In accordance with AMP DM 39-A-00-20-00-00A-120A- A , prepare the helicopter on ground for a safe maintenance. Disconnect the battery, all electrical power sources and/or the external power supply.

2. In accordance with AMP DM 39-A-71-11-07-00A-520A-A, remove the forward sliding fairing.

3. In accordance with AMP DM 39-A-63-20-00-00A-520A-A, remove the main gearbox.

4. Perform the MGB bearing lock-nut replacement as described in Annex A.

5. Record the compliance with this Service Bulletin on the MGB log card.

6. In accordance with AMP DM 39-A-63-20-00-00A-720A-A install the main gearbox.

7. In accordance with AMP DM 39-A-63-20-00-00A-364A-A, perform the MGB leak check.

With reference to figures A2 and A4 in Annex A, pay particular attention to:

 the junction between the upper module assembly and the main case assembly;

 the lip seal (46).

If no leakage is found, seal the junction line with sealing compound MC-780.

8. Protect the external surfaces with primer MIL-PRF-23377 and refinish paint, where required, applying two layers of High-Solids MIL-PRF-85285 Type I.

9. In accordance with AMP DM 39-A-71-11-07-00A-720A-A install the forward sliding fairing.

S.B. N°139-609 ALERT DATE: December 18, 2019 Page 10 of 28 REVISION: A - April 13, 2021

10. Return the helicopter to flight configuration and record for compliance with this Service Bulletin on the helicopter logbook.

11. Send the attached compliance form to the following mail box:

engineering.support.lhd@leonardocompany.com As an alternative, gain access to My Communications section on Leonardo WebPortal and compile the “Service Bulletin Application Communication”.

S.B. N°139-609 ALERT DATE: December 18, 2019 REVISION: A - April 13, 2021 Page 11 of 28

ANNEX A

MGB BEARING LOCK-NUT R

EPLACEMENT

S.B. N°139-609 ALERT DATE: December 18, 2019 Page 12 of 28 REVISION: A - April 13, 2021 The following procedure describes the replacement of MGB bearing lock-nut:

NOTE The MGB bearing lock-nut P/N 3G6320A09151 and P/N 3G6320A09152 will be referred to in this procedure as the ring nut.

1. With reference to Figure A3, cut and remove the lo ck wire between the check valve plug

(90) and the main case assembly.

2. With reference to Figure A3, remove the check valve plug (90) and the relevant packing

(91) from the main case assembly.

3. With reference to Figure A2 detail G, cut and remove the lock wire between the plug (27) and the main case assembly.

4. With reference to Figure A2 detail G, remove the plug (27) and the relevant packing (28) from the main case assembly

5. With reference to Figure A3 detail Q, cut and remove the lock wire between the oil relief valve (95) and the main case assembly.

6. With reference to Figure A3 detail Q, remove the oil relief valve (95) and the relevant packings (96) and (97) from the main case assembly.

7. With reference to Figure A2, remove the three nylon screws (26).

8. With reference to Figure A2 details A, B, C and D, remove nuts (15), washers (16), (17) and brackets (18), (19) and (20) in indicated positions.

9. Install the MGB lifting tool P/N 3G6320A00131A181A on the top of the mast.

10. Connect the lifting device to the MGB lifting tool P/N 3G6320A00131A181A.

CAUTION Performing following step 11, the ring fixed gear, that is part of the upper module assy, will remain installed on the main case assembly.

11. Lift with precaution the upper module until it is completely disconnected from the main case assembly.

12. Put the upper module on the upper module support trolley P/N 3G6320A00231A188A and lock it using the lifting tool upper module P/N 3G6320A00231A181B.

13. Remove the ring fixed gear from the main case assembly using the tool P/N 3G6320A00231A029F.

14. Remove the oil union (21) and the four oil unions (23) from the main case assembly, using the oil union extractor tool P/N 3G6320A00131A029A.

15. With reference to Figures A1 and A4, disassemble the upper module assy as described in the following procedure: