### Service Bulletin

12 January 2010

Revision 01, 01 November 2010 

# 340–32–139

Page 1 of 8 

### ATA CHAPTER: 32 LANDING GEAR – MAIN LANDING GEAR – REPLACEMENT OF THE HARNESS FOR THE SEPARATION BOLT Mod No. 3317

1. PLANNING INFORMATION

A. EFFECTIVITY (1) Aircraft: Aircraft Mfg. Serial No’s SAAB SF340A – 004 thru – 159. Aircraft Mfg. Serial No’s SAAB 340B – 160 thru – 459. NOTE : Service Bulletin 340–32–128 must be incorporated before or in conjunction with this SB. (2) Spares: Not affected.

B. REASON This Service Bulletin is issued to introduce a new improved separation bolt harness with a new routing. Incorporation of this Service Bulletin will give an improved harness installation and thus ensure correct function of the emergency system for the landing gear system.

C. DESCRIPTION This Service Bulletin gives instructions for: – Removal of the old separation bolt harness – Installation of the new improved separation bolt harness – Electrical system test of the separation bolt – Functional test of the landing gear extension and retraction system.

D. COMPLIANCE Mandatory. Saab recomends this Service Bulletin to be performed within 12 months from release of first issue of this SB. This Service Bulletin is under EASA consideration for an Airworthiness Directive (AD). The final compliance terms will be set by the EASA Airworthiness Directive when issued.

E. APPROVAL The technical content of this Service Bulletin is approved under the authority of DOA nr. EASA.21J.066.

F. MANPOWER Estimated time to complete this Service Bulletin is: 1 persons required. Total manhours: 10 Elapsed time (hours): 10

### Service Bulletin

12 January 2010

Revision 01, 01 November 2010 

# 340–32–139

Page 2 of 8 Labour cost at operators expense.

G. MATERIAL – COST AND AVAILABILITY Price and availability for Mod Kit. No. SAAB 340–32–139–01 will be furnished on request.

H. TOOLING (1) Faraday cage, quantity 2.

I. WEIGHT AND BALANCE No Change.

J. ELECTRICAL LOAD DATA Not affected.

K. REFERENCES Aircraft Maintenance Manual (AMM) 06–30–00 29–00–00 32–12–05 32–30–00 32–34–15 32–34–20. Wiring Manual (WM) 20–00–00.

L. OTHER PUBLICATIONS AFFECTED Aircraft Maintenance Manual (AMM) 32–34–17. Illustrated Parts Catalog (IPC) 32–30–00.

2. ACCOMPLISHMENT INSTRUCTIONS CAUTION : BE CAREFUL WHEN YOU DO THE MODIFICATION OF THE HARNESS. MAKE SURE THAT YOU DO NOT DAMAGE THE EXISTING WIRES WHEN NEW WIRES ARE INSTALLED. CLEAN AND INSPECT THE AFFECTED HARNESS WHEN THE MODIFICATION IS COMPLETED. DAMAGES TO THE WIRES CAN CAUSE SYSTEM MALFUNCTION. NOTE : All wiring changes are to be performed in accordance with the procedures in the WM 20–00–00. NOTE : The color of the lacing cord on the A and the B wire bundles gives the harness class and identification. The A harness is identified with white lacing cord and the B harness is identified with red/black lacing cord.

A. JOB SET–UP WARNING : MAKE SURE THE SAFETY PINS ARE INSTALLED IN THE NOSE LANDING GEAR AND IN THE MAIN LANDING GEAR. THE LANDING GEAR CAN RETRACT AND CAUSE INJURY TO PERSONS. (1) Before you start the SB, make sure: – The modification kit contains the parts listed in the Service Bulletin – The local supply items listed in the Service Bulletin are available – The documentation is available – The special tools are available.

### Service Bulletin

12 January 2010

Revision 01, 01 November 2010 

# 340–32–139

Page 3 of 8 (2) De–pressurize the hydraulic system (Ref. AMM 29–00–00). (3) Open the circuit breakers. On the LH circuit breaker panel 9VU, open, tag and safety the circuit breaker:

LABEL POS C/B L LDG EMER RELEAS E–9 1GB HYDRAULIC / LDG / CONTROL F–7 7GA HYDRAULIC / PUMP / AUTO F–9 11ML On the RH circuit breaker panel 10VU, open, tag and safety the circuit breaker:

LABEL POS C/B R LDG EMER RELEAS L–9 2GB (4) Open the main landing gear forward doors. Secure doors wide open (Ref. AMM 32–12–05). (5) Remove access panels 457AL and 467BR (Ref. AMM 06–30–00).

B. REMOVAL WARNING : THE SEPARATION BOLT IS AN EXPLOSIVE DEVICE. WEAR SAFETY GLASSES AND EAR PROTECTORS TO PREVENT POSSIBLE INJURY IF THE SEPARATION BOLT IS ACCIDENTLY DETONATED. REF. FIG. 1 (1) Remove the LH nacelle separation bolt harness. (a) Disconnect and cap electrical connector 3GB–P1 from the separation bolt receptacles. Install faraday cage on receptacle (Ref. AMM 32–34–15). (b) Remove harness (101) with bushings and the clamps (102). Save the bolts for installation of the new harness. (c) Remove ground wires at connector 3GB–J1A from ground point 570VN. (d) Disconnect connector 3GB–J1:A from 3GB–P1:A. (e) Discard the harness (101) and the clamps (102). (2) Remove the RH nacelle separation bolt harness. (a) Disconnect and cap electrical connector 4GB–P1 from the separation bolt receptacles. Install faraday cage on receptacle (Ref. AMM 32–34–15). (b) Remove harness (101) with bushings and the clamps (102). Save the bolts for installation of the new harness. (c) Remove ground wires at connector 4GB–J1A from ground point 670VN. (d) Disconnect connector 4GB–J1:A from 4GB–P1:A. (e) Discard the harness (101) and the clamps (102).

C. INSTALLATION REF. FIG. 1 (1) Install the new separation bolt harnesses to the LH nacelle. (a) Remove faraday cage from the separation bolt receptacle.

### Service Bulletin

12 January 2010

Revision 01, 01 November 2010 

# 340–32–139

Page 4 of 8 (b) Install a heat shrinkable sleeve with length 6 in (150 mm) to the harness (1), do not shrink at this time. (c) Install the harness (1) and connect the connector 3GB–J1A to the connector 3GB–P1A and the connector 3GB–P1 to the separation bolt receptacle. (d) Install the heat shrinkable sleeve over the connector 3GB and shrink into position using a heat gun. (e) Install ground wires at connector 3GB–J1A to ground point 570VN. (f) Install the clamp (2) and the two bolts. Do not tighten the bolt that holds the clamp (2) at this time. (g) Make sure that the length from the front face of the connector 3GB–P1 to the clamp (2) is approximately 11.4 in (290 mm). Adjust if necessary. (h) Tighten the bolt that holds the clamp (2). (i) Strap the harness (1), make sure that sufficient clearance between the harness, the connectors, the landing gear mechanism and the nacelle structure is obtained. (j) Seal the grounding point 570VN with sealant MIL–S–8802 or equivalent. (2) Install the new separation bolt harnesses to the RH nacelle. (a) Remove faraday cage from the separation bolt receptacle. (b) Install the heat shrinkable sleeve with length 6 in (150 mm) to the harness (1), do not shrink at this time. (c) Install the harness (1) and connect the connector 4GB–J1A to the connector 4GB–P1A and the connector 4GB–P1 to the separation bolt receptacle. (d) Install the heat shrinkable sleeve over the connector 4GB and shrink into position using a heat gun. (e) Install ground wires at connector 4GB–J1A to ground point 670VN. (f) Install the clamp (2) and the two bolts. Do not tighten the bolt that holds the clamp (2) at this time. (g) Make sure that the length from the front face of the connector 4GB–P1 to the clamp (2) is approximately 11.4 in (290 mm). Adjust if necessary. (h) Tighten the bolt that holds the clamp (2). (i) Strap the harness (1), make sure that sufficient clearance between the harness, the connectors, the landing gear mechanism and the nacelle structure is obtained. (j) Seal the grounding point 670VN with sealant MIL–S–8802 or equivalent.

D. JOB CLOSE–UP (1) Close the circuit breakers. On the LH circuit breaker panel 9VU, remove the tag and close the circuit breaker:

LABEL POS C/B L LDG EMER RELEAS E–9 1GB HYDRAULIC / LDG / CONTROL F–7 7GA HYDRAULIC / PUMP / AUTO F–9 11ML On the RH circuit breaker panel 10VU, remove the tag and close the circuit breaker:

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12 January 2010

Revision 01, 01 November 2010 

# 340–32–139

Page 5 of 8 LABEL POS C/B R LDG EMER RELEAS L–9 2GB (2) Do the electrical system test of the separation bolt (Ref. AMM 32–34–20). (3) Do the functional test of the landing gear extension and retraction system (Ref. AMM 32–30–00). Make sure that there is no interference between the MLG up–lock switch and the new harness installed. (4) Close the main landing gear forward doors (Ref. AMM 32–12–05). (5) Install access panels 457BR and 467BR (Ref. AMM 06–30–00).

3. MATERIAL INFORMATION

A. Modification Kit No SAAB 340–32–139–01 contains:

Item Part Number Qty Nomenclature Designation Remarks 1 7292520–691 2 Harness – – 2 M85052/1–6 2 Clamp – –

B. Local supply

Item Part Number Qty Nomenclature Designation Remarks – MIL–S–8802 AR Sealant 570/670VN – – MS3367–1 O/T MS3367–1–0 AR Strap – –

– Viton–E 1” O/T RW–200–E 1” 12 in (300mm) Shrinkable Sleeve 3GB/4GB –

NOTE : Equivalent materials can be used for listed items, Ref. SRM 51–33–00.

C. Removal

Item Part Number Qty Nomenclature Designation Remarks 101 7292520–678 2 Harness – – 102 MS21919WDG10 4 Clamp – –

### Service Bulletin

12 January 2010

Revision 1, 01 November 2010 

# 340–32–139

Page 6 of 8 

### THIS PAGE INTENTIONALLY LEFT BLANKService Bulletin12 January 2010Revision 01, 01 November 2010340–32–139Page 7/8 of 801101102102 02SEPARATION BOLTREF.A30643*APPLY SHRINK SLEEVE VITON 1 in (25 mm) OVERCONNECTORS LENGTH 6 in (150 mm).CONNECTOR LOCATION CAN VARY DUE TO MODIFICATIONS.*Separation Bolt Harness – Removal/InstallationFIG. 1

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Date Month Year

Revison X, Date Month Year 

# 340–XX–XXX

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