Flight Controls − Rudder Travel Limiting System − Inspection of the Return Springs and the Primary Actuator of the Rudder Travel Limiter
This page transmits: Revision A of Service Bulletin 670BA−27−055, pages 1 thru 24, dated Aug 06/2010. The changes in this revision have no effect on aircraft that have incorporated a previous issue of this service bulletin.
Reason:

Revised Material Information, paragraph 3., to: In the Consumables Information, change the Specification and the Reference of the polyurethane topcoat. This revision also includes small editorial changes that do not have an effect on the technical content.
Document Instructions: Discard the copy of Service Bulletin 670BA−27−055, dated May 11/2010. Replace with the copy attached. Service Bulletin History: Initial issue, dated May 11/2010. 

### SERVICE BULLETIN 670BA−27−055

S.B. 670BA−27−055 Page 1 of 1 Aug 06/2010 

# SERVICE BULLETIN REVISION TRANSMITTAL SHEET CL−600−2C10, CL−600−2D15 and CL−600−2D24

CANADAIR REGIONAL JET (CRJ) AIRCRAFT

SUBJECT:Flight Controls − Rudder Travel Limiting System − Inspection of the Return Springs and the Primary Actuator of the Rudder Travel Limiter

1. PLANNING INFORMATION A. Effectivity (1) Aircraft Affected: Service Bulletin: CL−600−2C10 Canadair Regional Jet (CRJ) Aircraft Serial Numbers 10003 thru 10999. Production: There is no production effectivity at this time. Service Bulletin: CL−600−2D15 Canadair Regional Jet (CRJ) and CL−600−2D24 Canadair Regional Jet (CRJ) Aircraft Serial Numbers 15001 thru 15990. Production: There is no production effectivity at this time. NOTE: The instructions in this service bulletin are only applicable to the systems and parts installed at the time of delivery of the aircraft or as changed by Bombardier Service Bulletin(s). Before you do this bulletin, examine all STC, STA or equivalent action changes to make sure this bulletin can be completed. 

# SERVICE BULLETIN

ATA SYSTEM: 27−25 NUMBER: 670BA−27−055

S.B. 670BA−27−055 Page 1 of 24 May 11/2010 Revision A, Aug 06/2010 Technical Publications

THIS SERVICE BULLETIN IS SENT TO EACH OPERATOR. IF THE OPERATOR HAS LEASED AIRCRAFT, THIS SERVICE BULLETIN MUST BE SENT TO THE LESSEE. IF THE OPERATOR HAS SOLD AIRCRAFT OR TRANSFERRED SPARES IN THE LAST SIX MONTHS, THIS SERVICE BULLETIN MUST BE SENT TO THE NEW OWNER, UNLESS CONFIRMATION WAS RECEIVED THAT BOMBARDIER COMMERCIAL AIRCRAFT DIVISION HAS INCLUDED THE NEW OPERATOR ON THE DISTRIBUTION LIST.

SUBJECT:B. Reason (1) Condition It is possible for the return springs of the rudder travel limiter to break because of fatigue or chafing by the primary actuator. (2) Evidence Return springs broke during endurance test. (3) Objective/Benefit This service bulletin gives the procedure to do a detailed visual inspection of the return springs and the primary actuator casing of the rudder travel limiter. This will make sure that the return springs are installed correctly on the rudder travel limiter. C. Description The rudder is moved to the neutral position. A rigging pin is installed in the rudder travel limiter. The electrical power is removed from the aircraft. Circuit breakers are opened. Access panels are removed. A detailed visual inspection of the return springs and the casing of the primary actuator is done. The rigging pin is removed from the rudder travel limiter. Circuit breakers are closed. If return springs are replaced, applicable return−to−service tests are done. Access panels are installed. D. Compliance Recommended Service Bulletin. For aircraft that have 4000 flight hours or less, Bombardier recommends that this service bulletin be done before the aircraft have 6000 flight hours, unless otherwise directed by the airworthiness authority of the operator. For aircraft that have more than 4000 flight hours, Bombardier recommends that this service bulletin be done no more than 2000 flight hours from the release date on this service bulletin, unless otherwise directed by the airworthiness authority of the operator. 

### SERVICE BULLETIN 670BA−27−055

S.B. 670BA−27−055 Page 2 of 24 May 11/2010 Revision A, Aug 06/2010Bombardier recommends that this service bulletin be repeated every 6000 flight hours from the initial inspection date of this service bulletin, unless otherwise directed by the airworthiness authority of the operator. NOTE: It is not necessary to do Service Bulletin 670BA−27

–047, Flight Controls − Rudder Travel Limiting System − Replacement of the Return Springs and Pulleys and Removal of the Torsion Spring, when this service bulletin is done. This service bulletin does not affect Airworthiness Limitations (AWLs) or Damage Tolerance inspections (DTIs). E. Approval The technical content of this service bulletin has been approved under the authority of the TCCA Design Approval Organization No: DAO #93−Q−02. F. Manpower The man−hours given below are an estimate for direct labor done by an experienced crew on an aircraft prepared for maintenance. This estimate does not include the time necessary for: − Administrative functions such as planning, liaison, familiarization, and report writing. − Non productive elapsed time such as rest time, having meals, and crew shift changes. − Elapsed time such as for paint to dry, sealant to cure, and fuel tank venting. − Preparation for modification (unless specified in the accomplishment instructions) such as cleaning and getting parts, tools, consumables, and ground equipment. − Quality assurance inspections, troubleshooting and/or correction of discrepancies found when a task is done. − All other activities that are not considered by Bombardier as directly related to the accomplishment of this procedure. NOTE: For any on−site labor assistance, please speak with a Fleet Services representative for a quote. The Fleet Services team can be contacted via the CRC at 514−855−8500 or email at thd.crj@aero.bombardier.com. It will take an estimated 6.5 man−hours to complete this service bulletin. The man−hours are divided as shown in the table that follows : 

### SERVICE BULLETIN 670BA−27−055

S.B. 670BA−27−055 Page 3 of 24 May 11/2010 Revision A, Aug 06/2010TASK MAN−HOURS (1) Job Set−Up 1.0 (2) Procedure 0.5 [1] [2] (3) Test 4.0 [3] (4) Job Close−Out 1.0 NOTE: [1] The man−hours given are for the inspection only. Add 3.0 man−hours to replace the return springs and the primary actuator. NOTE: [2] The man−hours given are for the inspection only. Add 2.0 man−hours to replace the return springs. NOTE: [3] The return−to−service tests are only applicable when return springs are replaced. G. Material − Price and Availability (1) There are no kits for this service bulletin. If necessary, use the parts in the table that follows to do this service bulletin. The parts are available from Bombardier commercial aircraft. Refer to the paragraph(s) below for terms and conditions. For Rudder Travel Limiter P/N KBA670−93402−1, KBA670−93402−3, KBA670−93402−5 and BA670−93470−15

PART NUMBER NAME QUANTITY BA670−93465−1 Spring, Return Maximum two for each aircraft For Rudder Travel Limiter P/N BA670−30000−7969, BA670−93470−7, BA670−93470−9, BA670−93470−13, BA670−93470−963, BA670−93470−979, BA670−93470−981, BA670−93470−987, BA670−93470−2001, KBA670−93470−1 and KBA670−93470−3

PART NUMBER NAME QUANTITY E0650−069−2750S Spring, Return Maximum two for each aircraft 

### SERVICE BULLETIN 670BA−27−055

S.B. 670BA−27−055 Page 4 of 24 May 11/2010 Revision A, Aug 06/2010For all Aircraft

PART NUMBER NAME QUANTITY BA670−93490−1 or BA670−93490−3 Actuator, Linear Maximum one for each aircraft (2) Please send a purchase order to the address below to schedule the part(s): Bombardier Service Bulletin Kit Support Team 123 Garratt Blvd, N42

–24 Toronto, Ontario Canada M3K 1Y5 Fax: 416−375−3060 Phone: 416−375−3920 email: sbkits@aero.bombardier.com Please contact your Service Bulletin Kit Support Team at the address above for terms and conditions. (3) Refer to paragraph 3.B. for a list of consumables for this service bulletin. H. Tooling − Price and Availability There are no tool kits for this service bulletin. (1) Refer to paragraph 3.C. for a list of special tools and equipment for this service bulletin. I. Weight and Balance Not changed. J. Electrical Load Data Not changed. K. References − Restriction and/or Special Instruction (RSI), C−27−1217−00, Revision B. − Aircraft Maintenance Manual (AMM), CSP B−001. − Structural Repair Manual (SRM), CSP B−008. 

### SERVICE BULLETIN 670BA−27−055

S.B. 670BA−27−055 Page 5 of 24 May 11/2010 Revision A, Aug 06/2010− For Bombardier reference only: PCA 73983. L. Other Publications Affected None. M. Relationship Chart Not applicable. 

### SERVICE BULLETIN 670BA−27−055

S.B. 670BA−27−055 Page 6 of 24 May 11/2010 Revision A, Aug 06/20102. ACCOMPLISHMENT INSTRUCTIONS A. Job Set−Up (1) Reference Information
REFERENCE DESIGNATION AMM 12−00−00−867−801 Standard Aircraft Configuration for Maintenance AMM 20−21−00−910−801 Torquing of Threaded Fasteners AMM 20−51−00−000−801 Removal of Cotter Pins AMM 20−51−00−400−801 Installation of Cotter Pins AMM 24−00−00−861−802 Remove Electrical Power from the Aircraft AMM 24−00−00−910−801 Electrical/Electronic Safety Precautions AMM 27−00−00−910−802 Flight−Control Safety Precautions AMM 27−21−00−710−801 Operational Test of the Rudder−Control−System AMM 27−21−00−864−801 Move the Rudder Control Surface in the Neutral Position AMM 27−25−00−710−801 Operational Test of the Rudder Travel Limiter AMM 27−25−03−000−801 Removal of the Rudder Travel Limiter Actuator AMM 27−25−03−400−801 Installation of the Rudder Travel Limiter Actuator AMM 27−25−03−820−801 Rigging Check of the Rudder Travel Limiter Actuator AMM 27−61−05−740−801 Self Test of the Spoiler and Stabilizer Control Units AMM 55−32−32−000−801 Removal of the Elevator−Quadrant Access Door (325EL/325ER) 

### SERVICE BULLETIN 670BA−27−055

S.B. 670BA−27−055 Page 7 of 24 May 11/2010 Revision A, Aug 06/2010REFERENCE DESIGNATION AMM 55−32−32−000−802 Removal of the Turnbuckle Autopilot−Controls Access Door (325DL) AMM 55−32−32−400−801 Installation of the Elevator−Quadrant Access Door (325EL/325ER) AMM 55−32−32−400−802 Installation of the Turnbuckle Autopilot−Controls Access Door (325DL) NDT M51−20−009−210 Visual

– Inspection Procedures SRM 51−25−06−001−001 Fluid−Resistant (FR) Epoxy Primer SRM 51−25−16−001−001 Fluid−Resistant (FR) Polyurethane Topcoat SRM 51−26−00−001−001 Cleaning SRM 51−41−02−001−001 Bolts, Screws and Related Items (2) Make sure that the aircraft is in standard configuration for maintenance (AMM 12−00−00−867−801). (3) Obey all the electrical/electronic safety precautions (AMM 24−00−00−910−801). (4) Obey all the flight−control safety precautions (AMM 27−00−00−910−802). (5) Remove the access panels that follow:

PANEL NAME REFERENCE 325DL Turnbuckle Autopilot−Controls Access Door AMM 55−32−32−000−802
325EL Elevator−Quadrant Access Door AMM 55−32−32−000−801 (6) Move the rudder control surface in the neutral position (AMM 27−21−00−864−801). 

### SERVICE BULLETIN 670BA−27−055

S.B. 670BA−27−055 Page 8 of 24 May 11/2010 Revision A, Aug 06/2010Refer to Figure 1. (7) Install rigging pin P1 in the rudder travel limiter. (8) Remove electrical power from the aircraft (AMM 24−00−00−861−802). (9) Open, safety, and tag the circuit breakers that follow:

CB−PANEL CB NO. NAME CBP−1 F1 SSCU 1 CH A CBP−1 F2 P FEEL 1 RTL 1 CBP−1 F11 HYD SYST AC PUMP CONT 3B CBP−1 F14 HYD SYST AC PUMP CONT 2 CBP−2 F1 SSCU 1 CH B CBP−2 F2 RUDDER TRIM CBP−2 F13 HYD SYST AC PUMP CONT 1 CBP−2 F14 HYD SYST AC PUMP CONT 3A CBP−2 LOWER R3 SSCU2 CH A CBP−2 LOWER R4 SSCU2 CH B CBP−2 LOWER R5 P FEEL 2 RTL 2 (10) Install warning placards on the rudder pedals to give warning not to move the rudder control surface. (11) Install warning placards on the control columns to give warning not to operate or move the flight controls. B. Procedure Refer to Figure 1 . (1) Do a detailed visual inspection of the casing of the primary actuator (1) for signs of chafing and make sure that the return springs (2) are not broken as follows: 

### SERVICE BULLETIN 670BA−27−055

S.B. 670BA−27−055 Page 9 of 24 May 11/2010 Revision A, Aug 06/2010(a) If there is no sign of chafing on the casing of the primary actuator (1) and the return springs (2) are not broken, go to the Job Close−Out. (b) If there is a sign of chafing on the casing of the primary actuator (1), do as follows: 1 If damage does not go through the casing of the primary actuator (1), do the steps that follow:
a Disconnect the electrical connector A203P1 (24) from the receptacle. b Install protective covers on the electrical connector A203P1 (24) and on the receptacle of the primary actuator (1).
c Remove the nut (3), the lock washer (4), the washer (5) and the bonding jumper (6). d Remove the spring (7) from the RTL spring bracket as follows: 1) Remove and discard the cotter pin (8). WARNING: BE CAREFUL WHEN YOU REMOVE THE SPRING. THE SPRING CAN HAVE LOAD AND CAUSE INJURIES TO PERSONS. 2) Hold the pulley (9) and the spring (7). 3) Remove the nut (10), the washers (11) and the bolt (12). 4) Remove the pulley (9) from the spring (7).
e Remove the bottom end of the primary actuator (1) as follows: 1) Remove the nut (13), the washer (14) and the screw (15). 2) Remove and discard the cotter pin (17). 3) Hold the primary actuator (1). For Aircraft 10003−10265 and 15001−15181 Pre−SB 670BA−27−047 4) Remove the nut (18), the washers (19) and (20), the springs (23), the bushing (21) and the bolt (22). 5) Hold the anti−rotation pad (16) when you move the bottom end of the primary actuator (1) from the limiter arm. 

### SERVICE BULLETIN 670BA−27−055

S.B. 670BA−27−055 Page 10 of 24 May 11/2010 Revision A, Aug 06/2010For Aircraft 10003−10265 and 15001−15181 Post−SB 670BA−27−047 and for Aircraft 10266−10999 and 15182−15990 6) Remove the nut (18), the washers (19) and (20), the bushing (21) and the bolt (22). 7) Hold the anti−rotation pad (16) when you move the bottom end of the primary actuator (1) from the limiter arm. For all Aircraft 8) Move the bottom end of the primary actuator (1) and attach it to the adjacent structure. f Apply fluid−resistant primer to the damaged area on the casing of the primary actuator (1). g Apply polyurethane topcoat to the damaged area on the casing of the primary actuator (1). h Remove and discard the return springs (2). For Rudder Travel Limiter P/N KBA670−93402−1, KBA670−93402−3, KBA670−93402−5 and BA670−93470−15 i Install new return springs (2) P/N BA670−93465−1. For Rudder Travel Limiter P/N BA670−30000−7969, BA670−93470−7, BA670−93470−9, BA670−93470−13, BA670−93470−963, BA670−93470−979, BA670−93470−981, BA670−93470−987, BA670−93470−2001, KBA670−93470−1 and KBA670−93470−3 j Install new return springs (2) P/N E0650−069−2750S. For all Aircraft k Connect the primary actuator (1) of the rudder travel limiter as follows: 1) Make sure that the primary actuator (1) of the rudder travel limiter is correctly rigged as follows: a) Put the primary actuator (1), the bushing (21) and the bolt (22) in position temporarily. b) Make sure that it is possible to install the bolt (22) and the bushing (21). 

### SERVICE BULLETIN 670BA−27−055

S.B. 670BA−27−055 Page 11 of 24 May 11/2010 Revision A, Aug 06/2010c) If it is not possible to install the bolt (22) and the bushing (21), do the rigging check of the rudder−travel limiter actuator (AMM 27−25−03−820−801). 2) Continue the installation of the primary actuator (1) as follows: a) Put the anti−rotation pad (16) and the bottom end of the primary actuator (1) in position on the rudder travel limiter. b) Align the holes in the anti−rotation pad (16) with the holes in the limiter arm. c) Clean the bushing (21) with solvent. d) Apply Mastinox or fluid−resistant primer to the bushing (21). For Aircraft 10003−10265 and 15001−15181 Pre−SB 670BA−27−047 e) Put the bushing (21) and the springs (23) in position in the limiter arm. For Aircraft 10003−10265 and 15001−15181 Post−SB 670BA−27−047 and for Aircraft 10266−10999 and 15182−15990 f) Put the bushing (21) in position in the limiter arm. For all Aircraft g) Make sure that the link assemblies align with the bushing (21). h) Install the bolt (22), the washers (19) and (20), and the nut (18). i) Attach the anti−rotation pad (16) with the bolt (15), the washer (14) and the nut (13). j) Safety the nut (18) with the cotter pin (17). 3) Install the spring (7) on the RTL spring bracket as follows: a) Attach the pulley (9) and the spring (7) together. 

### SERVICE BULLETIN 670BA−27−055

S.B. 670BA−27−055 Page 12 of 24 May 11/2010 Revision A, Aug 06/2010WARNING: BE CAREFUL WHEN YOU INSTALL THE SPRING. THE SPRING CAN HAVE LOAD AND CAUSE INJURIES TO PERSONS. b) Install the pulley (9) and the spring (7) on the RTL spring bracket with the bolt (12), the washers (11) and the nut (10). c) Safety the nut (10) with the cotter pin (8). 4) Install the bonding jumper (6), the washer (5), the lock washer (4) and the nut (3). 5) Remove the protective covers from the electrical connector A203P1 (24) and the receptacle of the primary actuator (1). 6) Connect the electrical connector A203P1 (24) to the receptacle. l Go to the Job Close−Out. 2 If the damage goes through the casing of the primary actuator (1), do the steps that follow:
a Remove the A203 primary actuator (1) (AMM 27−25−03−000−801). b Remove and discard the return springs (2). For Rudder Travel Limiter P/N KBA670−93402−1, KBA670−93402−3, KBA670−93402−5 and BA670−93470−15
c Install the new return springs (2) P/N BA670−93465−1. For Rudder Travel Limiter P/N BA670−30000−7969, BA670−93470−7, BA670−93470−9, BA670−93470−13, BA670−93470−963, BA670−93470−979, BA670−93470−981, BA670−93470−987, BA670−93470−2001, KBA670−93470−1 and KBA670−93470−3 d Install the new return springs (2) P/N E0650−069−2750S. For all Aircraft
e Install the new A203 primary actuator (1) (AMM 27−25−03−400−801). 

### SERVICE BULLETIN 670BA−27−055

S.B. 670BA−27−055 Page 13 of 24 May 11/2010 Revision A, Aug 06/2010(c) If there is no sign of chafing on the casing of the primary actuator (1) and the return spring(s) (2) is broken, do the steps that follow: 1 Disconnect the electrical connector A203P1 (24) from receptacle. 2 Install protective covers on the electrical connector A203P1 (24) and on the receptacle of the primary actuator (1). 3 Remove the spring (7) from the RTL spring bracket as follows:
a Remove and discard the cotter pin (8). WARNING: BE CAREFUL WHEN YOU REMOVE THE SPRING. THE SPRING CAN HAVE LOAD AND CAUSE INJURIES TO PERSONS. b Hold the pulley (9) and the spring (7).
c Remove the nut (10), the washers (11) and the bolt (12). d Remove the pulley (9) from the spring (7). 4 Remove the bottom end of the primary actuator (1) as follows:
a Remove the nut (13), the washer (14) and the screw (15). b Remove and discard the cotter pin (17).
c Hold the primary actuator (1). For Aircraft 10003−10265 and 15001−15181 Pre−SB 670BA−27−047 d Remove the nut (18), the washers (19) and (20), the springs (23), the bushing (21) and the bolt (22).
e Hold the anti−rotation pad (16) when you move the bottom end of the primary actuator (1) from the limiter arm. For Aircraft 10003−10265 and 15001−15181 Post−SB 670BA−27−047 and for Aircraft 10266−10999 and 15182−15990 f Remove the nut (18), the washers (19) and (20), the bushing (21) and the bolt (22). g Hold the anti−rotation pad (16) when you move the bottom end of the primary actuator (1) from the limiter arm. 

### SERVICE BULLETIN 670BA−27−055

S.B. 670BA−27−055 Page 14 of 24 May 11/2010 Revision A, Aug 06/2010For all Aircraft h Move the bottom end of the primary actuator (1) and attach it to the adjacent structure. 5 Remove and discard the broken return spring(s) (2). For Rudder Travel Limiter P/N KBA670−93402−1, KBA670−93402−3, KBA670−93402−5 and BA670−93470−15 6 Install the new return spring(s) (2) P/N BA670−93465−1. For Rudder Travel Limiter P/N BA670−30000−7969, BA670−93470−7, BA670−93470−9, BA670−93470−13, BA670−93470−963, BA670−93470−979, BA670−93470−981, BA670−93470−987, BA670−93470−2001, KBA670−93470−1 and KBA670−93470−3 7 Install the new return spring(s) (2) P/N E0650−069−2750S. For all Aircraft 8 Connect the primary actuator (1) of the rudder travel limiter as follows:
a Make sure that the primary actuator (1) of the rudder travel limiter is correctly rigged as follows: 1) Put the primary actuator (1), the bushing (21) and the bolt (22) in position temporarily. 2) Make sure that it is possible to install the bolt (22) and the bushing (21). 3) If it is not possible to install the bolt (22) and the bushing (21), do the rigging check of the rudder−travel limiter actuator (AMM 27−25−03−820−801). b Continue the installation of the primary actuator (1) as follows: 1) Put the anti−rotation pad (16) and the bottom end of the primary actuator (1) in position on the rudder travel limiter. 2) Align the holes in the anti−rotation pad (16) with the holes in the limiter arm. 3) Clean the bushing (21) with solvent. 

### SERVICE BULLETIN 670BA−27−055

S.B. 670BA−27−055 Page 15 of 24 May 11/2010 Revision A, Aug 06/20104) Apply Mastinox or fluid−resistant primer to the bushing (21). For Aircraft 10003−10265 and 15001−15181 Pre−SB 670BA−27−047 5) Put the bushing (21) and the springs (23) in position in the limiter arm. For Aircraft 10003−10265 and 15001−15181 Post−SB 670BA−27−047 and for Aircraft 10266−10999 and 15182−15990 6) Put the bushing (21) in position in the limiter arm. For all Aircraft 7) Make sure that the link assemblies align with the bushing (21). 8) Install the bolt (22), the washers (19) and (20), and the nut (18). 9) Attach the anti−rotation pad (16) with the bolt (15), the washer (14) and the nut (13). 10) Safety the nut (18) with the cotter pin (17).
c Install the spring (7) on the RTL spring bracket as follows: 1) Attach the pulley (9) and the spring (7) together. WARNING: BE CAREFUL WHEN YOU INSTALL THE SPRING. THE SPRING CAN HAVE LOAD AND CAUSE INJURIES TO PERSONS. 2) Install the pulley (9) and the spring (7) on the RTL spring bracket with the bolt (12), the washers (11) and the nut (10). 3) Safety the nut (10) with the cotter pin (8). d Install the bonding jumper (6), the washer (5), the lock washer (4) and the nut (3).
e Remove the protective covers from the electrical connector A203P1 (24) and the receptacle of the primary actuator (1). 

### SERVICE BULLETIN 670BA−27−055

S.B. 670BA−27−055 Page 16 of 24 May 11/2010 Revision A, Aug 06/2010f Connect the electrical connector A203P1 (24) to the receptacle. 

### SERVICE BULLETIN 670BA−27−055

S.B. 670BA−27−055 Page 17 of 24 May 11/2010 Revision A, Aug 06/2010ba6402a01.cgm A

ROTATED AT 90° CLOCKWISE B

B 1

2 A

LEGEND 1. Primary actuator (BA670−93490−1 or BA670−93490−3). 2. Return springs (BA670−93465−1 or E0650−069−2750S). CASING (REF.) 

### SERVICE BULLETIN 670BA−27−055

Primary Actuator of the Rudder Travel Limiter Figure 1 (Sheet 1 of 3)

S.B. 670BA−27−055 Page 18 of 24 May 11/2010 Revision A, Aug 06/2010ba6401a02.cgm D

A

NOTES Installed on aircraft 10003−10265 and 15001−15181 Pre−SB 670BA−27−047 only. MS24665−132 is installed on aircraft 10003−10265 and 15001−15181 Pre−SB 670BA−27−047. MS24665−69 is installed on aircraft 10003−10265 and 15001−15181 Post−SB 670BA−27−047 and 10266−10999 and 15182−15990. 1 2 1. Primary actuator. 2. Return springs (BA670−93465−1 or E0650−069−2750S). 13. Nut. 14. Washer. 15. Screw. 16. Anti−rotation pad. 17. Cotter pin MS24665−69 or MS24665−132. 18. Nut. 19. Washer. 20. Washer. 21. Bushing. 22. Bolt. 23. Spring. LEGEND

22 15 21

LINK ASSEMBLY (REF) 20 18 17 19 23

1 1614 13 LINK ASSEMBLY (REF)

D LIMITER ARM (REF) 1

2 2 

### SERVICE BULLETIN 670BA−27−055

Primary Actuator of the Rudder Travel Limiter Figure 1 (Sheet 2 of 3)

S.B. 670BA−27−055 Page 19 of 24 May 11/2010 Revision A, Aug 06/2010ba6401a01.cgm 3 45 24

1

6 SECONDARY ACTUATOR (REF) RECEPTACLE (REF) P1

A B C

A

B

C 1

12

9 11 11 10 8 7 RTL SPRING BRACKET (REF) LEGEND 1. Primary actuator. 3. Nut. 4. Lock washer. 5. Washer. 6. Bonding jumper. 7. Spring. 8. Cotter pin MS24665−69. 9. Pulley. 10. Nut. 11. Washer. 12. Bolt. 24. Electrical connector A203P1. P. Rigging pin. 

### SERVICE BULLETIN 670BA−27−055

Primary Actuator of the Rudder Travel Limiter Figure 1 (Sheet 3 of 3)

S.B. 670BA−27−055 Page 20 of 24 May 11/2010 Revision A, Aug 06/2010C. Job Close−Out (1) Remove all tools, equipment, and unwanted materials from the work area. Refer to Figure 1. (2) Remove the rigging pin P1 from the rudder travel limiter. (3) Remove the tags and close the circuit breakers that follow:

CB−PANEL CB NO. NAME CBP−1 F1 SSCU 1 CH A CBP−1 F2 P FEEL 1 RTL 1 CBP−1 F11 HYD SYST AC PUMP CONT 3B CBP−1 F14 HYD SYST AC PUMP CONT 2 CBP−2 F1 SSCU 1 CH B CBP−2 F2 RUDDER TRIM CBP−2 F13 HYD SYST AC PUMP CONT 1 CBP−2 F14 HYD SYST AC PUMP CONT 3A CBP−2 LOWER R3 SSCU2 CH A CBP−2 LOWER R4 SSCU2 CH B CBP−2 LOWER R5 P FEEL 2 RTL 2 (4) Install the access panels that follow:

PANEL NAME REFERENCE 325DL Turnbuckle Autopilot−Controls Access Door AMM 55−32−32−400−802
325EL Elevator−Quadrant Access Door AMM 55−32−32−400−801 

### SERVICE BULLETIN 670BA−27−055

S.B. 670BA−27−055 Page 21 of 24 May 11/2010 Revision A, Aug 06/2010(5) Remove warning placards from the rudder pedals. (6) Remove warning placards from the control columns. (7) If return springs are replaced, do an operational test of the rudder travel limiter (AMM 27−25−00−710−801). (8) If return springs are replaced, do an operational test of the rudder−control−system (AMM 27−21−00−710−801). (9) If return springs are replaced, do a self test of the spoiler and stabilizer control units (AMM 27−61−05−740−801). (10) When this service bulletin is completed, make this entry in the applicable logbook(s): "Service Bulletin 670BA−27−055, Revision A, Flight Controls − Rudder Travel Limiting System − Inspection of the Return Springs and the Primary Actuator of the Rudder Travel Limiter, incorporated." 

### SERVICE BULLETIN 670BA−27−055

S.B. 670BA−27−055 Page 22 of 24 May 11/2010 Revision A, Aug 06/20103. MATERIAL INFORMATION A. Kit Information None. B. Consumable Information The materials that follow are necessary to do this service bulletin and can be ordered from Bombardier or purchased directly from industry sources. If the material is ordered from Bombardier, there can be some lead time because of shelf life of the material.
CONSUMABLES
SPECIFICATION QUANTITY NAME REFERENCE BAMS 565−002 As necessary Polyurethane Topcoat, Fluid−Resistant (Color grey (16473), FED−STD 595B) 07−019 [1]

6856K As necessary Mastinox, Corrosion Inhibitor 13−001 [1]

BAMS 565

–001 As necessary Fluid−Resistant Epoxy Primer 13

–006 [1] [1] Refer to AMM 51−31−00−992−801. NOTE: To complete this list of consumables, refer to the different tasks given as references in this service bulletin. C. Special Tools and Equipment 

### SERVICE BULLETIN 670BA−27−055

S.B. 670BA−27−055 Page 23 of 24 May 11/2010 Revision A, Aug 06/2010SPECIAL TOOLS AND EQUIPMENT

PART NUMBER QUANTITY NAME ALTERNATE PART(S)
G601R270001−1 1 Pins Kit − Rigging or equivalent [1] Refer to the Illustrated Tool and Equipment Manual (CSP B−007). NOTE: To complete this list of special tools and equipment, refer to the different tasks given as references in this service bulletin. D. Disposition of Parts Not applicable. 

### SERVICE BULLETIN 670BA−27−055

S.B. 670BA−27−055 Page 24 of 24 May 11/2010 Revision A, Aug 06/2010THANK YOU FOR ANSWERING THIS EVALUATION FORM UPON COMPLETION OF THIS EVALUATION FORM/COMPLIANCE SHEET, FAX TO 450-476-7300 

### SERVICE BULLETIN EVALUATION FORM/COMPLIANCE SHEET (YOUR IDEAS WILL HELP US PROVIDE BETTER BULLETINS)
SERVICE BULLETIN : 670BA-27-055 ISSUE: A

STRONGLY DISAGREE NEUTRAL AGREE STRONGLY DISAGREE AGREE
Instructions to do the Service Bulletin were accurate. Comments: 

## Illustration(s), figure(s), picture(s) and/or kit drawing(s) were helpful to carry out instructions. Comments: 

## If a parts kit was required, did the kit contents received agree with the contents listed in the bulletin? Comments: 

## Aircraft hands-on work was accomplished in estimated time. Comments: 

## Overall, I was satisfied with this Service Bulletin. Comments: 

## PLEASE SUPPLY US WITH THE FOLLOWING DATA AND FAX TO (450) 476-7300: OPERATOR: NAME (Please print) SERVICE CENTER: TELEPHONE: AIRCRAFT SERIAL NO.: FACSIMILE: DATE OF SB INCORPOARTION