Landing Gear − Brake System − Replacement of Accumulator P/N 0860204001 by P/N 90006691
These pages transmit: Revision A of Service Bulletin 670BA−32−028, pages 1 thru 17, dated Feb 03/2011. The changes in this revision have no effect on aircraft that have incorporated a previous issue of this service bulletin.
Reason:

Revised Planning Information, paragraph 1., to: Add CL−600−2B19 model in Evidence, paragraph 1. (2). Change the address in Material − Price and Availability, paragraph 1.G.(2). Add Meggitt Aircraft Braking Systems Service Information Letter in References, paragraph 1.K. Revised Accomplishment Instructions, paragraph 2., to: Change part number 086024001 for 0860204001 in figure 1. 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−32−028, dated Dec 22/2010. Replace with the copy attached. 

### SERVICE BULLETIN 670BA−32−028

S.B. 670BA−32−028 Page 1 of 2 Feb 03/2011 

# SERVICE BULLETIN REVISION TRANSMITTAL SHEET CL−600−2C10, CL−600−2D15, CL−600−2D24 and CL−600−2E25 CANADAIR REGIONAL JET (CRJ) AIRCRAFT

SUBJECT:Service Bulletin History: Initial issue, dated Dec 22/2010. 

### SERVICE BULLETIN 670BA−32−028

S.B. 670BA−32−028 Page 2 of 2 Feb 03/2011Landing Gear − Brake System − Replacement of Accumulator P/N 0860204001 by P/N 90006691

1. PLANNING INFORMATION A. Effectivity (1) Aircraft Affected: Service Bulletin: CL−600−2C10 Canadair Regional Jet (CRJ) Aircraft Serial Numbers 10003 thru 10314. Production: This change will be incorporated before delivery on Aircraft Serial Numbers 10315 and subsequent. Service Bulletin: CL−600−2D15 Canadair Regional Jet (CRJ) and CL−600−2D24 Canadair Regional Jet (CRJ) Aircraft Serial Numbers 15001 thru 15259. NOTE : This service bulletin was incorporated before delivery in aircraft serial numbers 15233, 15234, and 15239. Production: This change will be incorporated before delivery on Aircraft Serial Numbers 15260 and subsequent. 

# SERVICE BULLETIN

ATA SYSTEM: 32−43 NUMBER: 670BA−32−028

S.B. 670BA−32−028 Page 1 of 17 Dec 22/2010 Revision A, Feb 03/2011 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: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. B. Reason (1) Condition It is possible for the accumulator screw caps of the inboard and outboard brake accumulators to disconnect and cause damage to the aircraft structure and systems. (2) Evidence Seven CL−600−2B19 in−service aircraft had one screw cap disconnected from the body of the accumulator. (3) Objective/Benefit This service bulletin gives the procedure to replace the accumulators of the inboard and outboard brakes. The replacement of accumulator P/N 0860204001 by P/N 90006691 will prevent the disconnection of the screw caps from the body of the accumulator. C. Description This service bulletin is divided into two parts: PART A and PART B. PART A − Installation of the new inboard brake accumulator The hydraulic pressure is released from hydraulic system No. 3. Circuit breakers are opened. The electrical power is removed from the aircraft. The main avionic−compartment and the electrical bay doors are opened. The hydraulic access door is removed. The inboard brake accumulator is removed. A new inboard brake accumulator is installed. The circuit breakers are closed. The servicing of the inboard brake accumulator and the hydraulic system No. 3 reservoir is done. The inboard brakes and hydraulic system No. 3 are bled. An operational check of the inboard brake accumulator is done. The hydraulic access door is installed. The electrical bay and the main avionic−compartment doors are closed. PART B − Installation of the new outboard brake accumulator 

### SERVICE BULLETIN 670BA−32−028

S.B. 670BA−32−028 Page 2 of 17 Dec 22/2010 Revision A, Feb 03/2011The hydraulic pressure is released from hydraulic system No. 2. Circuit breakers are opened. The electrical power is removed from the aircraft. The main avionic−compartment and the electrical bay doors are opened. The outboard brake accumulator is removed. A new outboard brake accumulator is installed. The circuit breakers are closed. The servicing of the outboard brake accumulator and the hydraulic system No. 2 reservoir is done. The outboard brakes and hydraulic system No. 2 are bled. An operational check of the outboard brake accumulator is done. The hydraulic access door is installed. The electrical bay and the main avionic−compartment doors are closed. D. Compliance Recommended Service Bulletin. Bombardier recommends that this service bulletin be done no more than 4000 flight cycles from the release date on this service bulletin or no later than 2 years from the release date on this service bulletin, whichever comes first, unless otherwise directed by the airworthiness authority of the operator. NOTE : It is not necessary to do Service Bulletin 670BA−32−021, Landing Gear − Brake System − Inspection of the Accumulator Screw−Caps (P/N 0860204001), when this service bulletin is done. NOTE : It is not necessary to do Service Bulletin 670BA−32−026, Landing Gear − Brake System − Detailed Inspection of the Accumulator Screw−Caps Threads, when this service bulletin is done. 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 estimates for direct labor done by an experienced crew on an aircraft prepared for maintenance. These estimates do 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. 

### SERVICE BULLETIN 670BA−32−028

S.B. 670BA−32−028 Page 3 of 17 Dec 22/2010 Revision A, Feb 03/2011− 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 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. PART A − Installation of the new inboard brake accumulator It will take an estimated 3.5 man−hours to complete PART A of this service bulletin. The man−hours are divided as shown in the table that follows:

TASK MAN−HOURS (1) Job Set−Up 1.0 (2) Procedure 1.0 (3) Test 1.0 (4) Job Close−Out 0.5
PART B − Installation of the new outboard brake accumulator It will take an estimated 3.5 man−hours to complete PART B of this service bulletin. The man−hours are divided as shown in the table that follows:

TASK MAN−HOURS (1) Job Set−Up 1.0 (2) Procedure 1.0 (3) Test 1.0 (4) Job Close−Out 0.5 

### SERVICE BULLETIN 670BA−32−028

S.B. 670BA−32−028 Page 4 of 17 Dec 22/2010 Revision A, Feb 03/2011G. Material − Price and Availability (1) There are no kits for this service bulletin. The part in the table that follows is necessary to do this service bulletin. Refer to the paragraph below for terms and conditions.

PART NUMBER NAME QUANTITY 90006691 Accumulator 1[1] [1] One accumulator is necessary to do each PART of this service bulletin. (2) Please send a purchase order to the address below to schedule the part(s): Meggitt Aircraft Braking Systems (MABS) Attn: Mr Tom Borgmann, Warranty Administrator 1204 Massillon Road Akron, Ohio 44306−4186

USA Fax: 330−796−3420 Phone: 330−796−7200 email: tom.borgmann@meggit.com Please contact MABS 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 PART A − Installation of the new inboard brake accumulator

WEIGHT ARM MOMENT [1] 0.8 (lb) 185.2 (in.) 0.15 (1000 lb·in) 0.36 (kg) 4.7 (m) 0.0017 (1000 kg·m) 

### SERVICE BULLETIN 670BA−32−028

S.B. 670BA−32−028 Page 5 of 17 Dec 22/2010 Revision A, Feb 03/2011WEIGHT ARM MOMENT [1] [1] The value in the Moment column is divided by 1000. Refer to the Weight & Balance Manual CSP B−041 or CSP C−041. PART B − Installation of the new outboard brake accumulator

WEIGHT ARM MOMENT [1] 0.8 (lb) 185.2 (in.) 0.15 (1000 lb·in) 0.36 (kg) 4.7 (m) 0.0017 (1000 kg·m) [1] The value in the Moment column is divided by 1000. Refer to the Weight & Balance Manual CSP B−041 or CSP C−041.
J. Electrical Load Data Not changed. K. References − Restriction and/or Special Instruction (RSI), C−32−1210−00. − Modification Summary 670T095002, Revision A−2. − Bombardier Regional Jet Series All Operator Message (AOM), No. 614. − Meggitt Aircraft Braking Systems Service Information Letter 90006691

– SL−01. − Aircraft Maintenance Manual (AMM), CSP B−001. − For Bombardier reference only: PCA 73565, 74256, and DCP AB670−23002. L. Other Publications Affected − Aircraft Illustrated Parts Catalog (IPC), CSP B−006. − Aircraft Illustrated Parts Catalog (IPC), CSP C−006. 

### SERVICE BULLETIN 670BA−32−028

S.B. 670BA−32−028 Page 6 of 17 Dec 22/2010 Revision A, Feb 03/2011M. Relationship Chart

PRE−SB

PART NUMBER NAME POST−SB PART NUMBER NAME

0860204001 Accumulator 90006691 Accumulator 

### SERVICE BULLETIN 670BA−32−028

S.B. 670BA−32−028 Page 7 of 17 Dec 22/2010 Revision A, Feb 03/20112. ACCOMPLISHMENT INSTRUCTIONS PART A − Installation of the new inboard brake accumulator A. Job Set−Up (1) Reference Information
REFERENCE DESIGNATION AMM 12−00−00−867−801 Standard Aircraft Configuration for Maintenance AMM 12−00−06−862−804 Release Hydraulic Pressure of System No. 3 AMM 12−12−29−611−802 Servicing of the Hydraulic System No. 3 Reservoir AMM 12−12−29−614−801 Servicing of the Hydraulic System Accumulators AMM 24−00−00−861−802 Remove Electrical Power from the Aircraft AMM 24−00−00−910−801 Electrical/Electronic Safety Precautions AMM 29−00−00−910−802 Hydraulic Technical Precautions AMM 29−10−00−870−802 Bleed Hydraulic System No. 3 AMM 32−43−00−870−801 Bleeding of the Brakes AMM 32−43−16−000−801 Removal of the Brake Accumulator AMM 32−43−16−400−801 Installation of the Brake Accumulator AMM 32−43−16−710−801 Operational Test of the Brake Accumulator (2) Make sure that the aircraft is in standard configuration for maintenance (AMM 12−00−00−867−801). 

### SERVICE BULLETIN 670BA−32−028

S.B. 670BA−32−028 Page 8 of 17 Dec 22/2010 Revision A, Feb 03/2011(3) Obey all the hydraulic technical precautions (AMM 29−00−00−910−802). WARNING : OBEY ALL HYDRAULIC SAFETY PRECAUTIONS WHEN YOU DO WORK ON THE HYDRAULIC SYSTEM AND HYDRAULIC SYSTEM COMPONENTS. YOU CAN CAUSE INJURY TO PERSONS AND DAMAGE TO EQUIPMENT. (4) Release the hydraulic pressure from hydraulic system No. 3 (AMM 12−00−06−862−804). (5) Operate the brake pedals of the pilot or co−pilot to release the hydraulic pressure from the brake accumulators (approximately six times). WARNING : OBEY ALL THE SAFETY PRECAUTIONS WHEN YOU DO MAINTENANCE ON OR NEAR ELECTRICAL/ELECTRONIC EQUIPMENT. YOU CAN CAUSE INJURY TO PERSONS AND/OR DAMAGE TO EQUIPMENT. (6) Obey all the electrical/electronic safety precautions (AMM 24−00−00−910−801). (7) Open, safety, and tag the circuit breakers that follow:

CB−PANEL CB NO. NAME CBP−1 F11 HYD SYST AC PUMP CONT 3B CBP−2 F14 HYD SYST AC PUMP CONT 3A ACPC ACPC HYD PUMP 3A ACPC ACPC HYD PUMP 3B (8) Remove the electrical power from the aircraft (AMM 24−00−00−861−802). (9) Open electrical bay door 211AL. (10) Open main avionic−compartment door 811. B. Procedure Refer to Figure 1. (1) Remove the inboard brake accumulator (1) (AMM 32−43−16−000−801). 

### SERVICE BULLETIN 670BA−32−028

S.B. 670BA−32−028 Page 9 of 17 Dec 22/2010 Revision A, Feb 03/2011(2) Install the new inboard brake accumulator (1) (AMM 32−43−16−400−801). 

### SERVICE BULLETIN 670BA−32−028

S.B. 670BA−32−028 Page 10 of 17 Dec 22/2010 Revision A, Feb 03/2011LEGEND 1. Inboard brakes accumulator 0860204001 (Pre−Mod), 90006691 (Post−Mod). 2. Outboard brakes accumulator 0860204001 (Pre−Mod), 90006691 (Post−Mod).

1 Aba6701a01.cgm, eg, jun 18/2010

A 2 

### SERVICE BULLETIN 670BA−32−028

Accumulators of the Inboard and Outboard Brakes − Removal/Installation Figure 1 (Sheet 1 of 1)

S.B. 670BA−32−028 Page 11 of 17 Dec 22/2010 Revision A, Feb 03/2011C. Job Close−Out (1) Remove all tools, equipment, and unwanted materials from the work area. (2) Remove the tags and close the circuit breakers that follows:

CB−PANEL CB NO. NAME CBP−1 F11 HYD SYST AC PUMP CONT 3B CBP−2 F14 HYD SYST AC PUMP CONT 3A ACPC ACPC HYD PUMP CONT 3B ACPC ACPC HYD PUMP CONT 3A (3) Do the servicing of the inboard brake accumulator (AMM 12−12−29−614−801). (4) Do the servicing of the No. 3 hydraulic system reservoir (AMM 12−12−29−611−802). (5) Bleed hydraulic system No. 3 (AMM 29−10−00−870−802). (6) Bleed the inboard brakes (AMM 32−43−00−870−801). (7) Do an operational test of the inboard brake accumulator (AMM 32−43−16−710−801). (8) Close the electrical bay door 211AL. (9) Close the main avionic−compartment door 811. (10) When PART A of this service bulletin is completed, add the weight and balance data shown in paragraph 1.I. of this service bulletin to the Weight and Balance Manual. Under ‘Description of Change’ enter "Service Bulletin 670BA−32−028, Revision A, PART A, incorporated." (11) When PART A of this service bulletin is completed, make this entry in the applicable logbook(s): "Service Bulletin 670BA−32−028, Revision A, Landing Gear − Brake System − Replacement of Accumulator P/N 0860204001 by P/N 90006691, PART A, incorporated." 

### SERVICE BULLETIN 670BA−32−028

S.B. 670BA−32−028 Page 12 of 17 Dec 22/2010 Revision A, Feb 03/2011PART B − Installation of the new outboard brake accumulator A. Job Set−Up (1) Reference Information
REFERENCE DESIGNATION AMM 12−00−00−867−801 Standard Aircraft Configuration for Maintenance AMM 12−00−06−862−802 Release Hydraulic Pressure of System No. 1 and No. 2 AMM 12−12−29−611−801 Servicing of the Hydraulic System No. 1 and No. 2 Reservoirs AMM 12−12−29−614−801 Servicing of the Hydraulic System Accumulators AMM 24−00−00−861−802 Remove Electrical Power from the Aircraft AMM 24−00−00−910−801 Electrical/Electronic Safety Precautions AMM 29−00−00−910−802 Hydraulic Technical Precautions AMM 29−10−00−870−801 Bleed Hydraulic System No. 1 and No. 2 AMM 32−43−00−870−801 Bleeding of the Brakes AMM 32−43−16−000−801 Removal of the Brake Accumulator AMM 32−43−16−400−801 Installation of the Brake Accumulator AMM 32−43−16−710−801 Operational Test of the Brake Accumulator AMM 52−45−56−000−801 Removal of the Hydraulic Access Door (121AL) AMM 52−45−56−400−801 Installation of the Hydraulic Access Door (121AL) 

### SERVICE BULLETIN 670BA−32−028

S.B. 670BA−32−028 Page 13 of 17 Dec 22/2010 Revision A, Feb 03/2011(2) Make sure that the aircraft is in standard configuration for maintenance (AMM 12−00−00−867−801). (3) Obey all the hydraulic technical precautions (AMM 29−00−00−910−802). WARNING : OBEY ALL HYDRAULIC SAFETY PRECAUTIONS WHEN YOU DO WORK ON THE HYDRAULIC SYSTEM AND HYDRAULIC SYSTEM COMPONENTS. YOU CAN CAUSE INJURY TO PERSONS AND DAMAGE TO EQUIPMENT. (4) Release the hydraulic pressure from hydraulic system No. 2 (AMM 12−00−06−862−802). (5) Operate the brake pedals of the pilot or co−pilot to release the hydraulic pressure from the brake accumulators (approximately six times). WARNING : OBEY ALL THE SAFETY PRECAUTIONS WHEN YOU DO MAINTENANCE ON OR NEAR ELECTRICAL/ELECTRONIC EQUIPMENT. YOU CAN CAUSE INJURY TO PERSONS AND/OR DAMAGE TO EQUIPMENT. (6) Obey all the electrical/electronic safety precautions (AMM 24−00−00−910−801). (7) Open, safety, and tag the circuit breakers that follow:

CB−PANEL CB NO. NAME CBP−1 F14 HYD SYST AC PUMP CONT 2 ACPC ACPC HYD PUMP 2 (8) Remove electrical power from the aircraft (AMM 24−00−00−861−802). (9) Open the electrical bay door 211AL. (10) Open the main avionic−compartment door 811. 

### SERVICE BULLETIN 670BA−32−028

S.B. 670BA−32−028 Page 14 of 17 Dec 22/2010 Revision A, Feb 03/2011(11) Remove hydraulic access door 121AL (AMM 52−45−56−000−801). B. Procedure Refer to Figure 1. (1) Remove the outboard brake accumulator (1) (AMM 32−43−16−000−801). (2) Install the new outboard brake accumulator (1) (AMM 32−43−16−400−801). C. Job Close−Out (1) Remove all tools, equipment, and unwanted materials from the work area. (2) Remove the tags and close the circuit breakers that follow:

CB−PANEL CB NO. NAME CBP−1 F14 HYD SYST AC PUMP CONT 2 ACPC ACPC HYD PUMP CONT 2 (3) Do the servicing of the outboard brake accumulator (AMM 12−12−29−614−801). (4) Do the servicing of the No. 2 hydraulic system reservoir (AMM 12−12−29−611−801). (5) Bleed hydraulic system No. 2 (AMM 29−10−00−870−801). (6) Bleed the outboard brakes(AMM 32−43−00−870−801). (7) Do an operational test of the outboard brake accumulator (AMM 32−43−16−710−801). (8) Install the hydraulic access door 121AL (AMM 52−45−56−400−801). (9) Close the electrical bay door 211AL. (10) Close the main avionic−compartment door 811. (11) When PART B of this service bulletin is completed, add the weight and balance data shown in paragraph 1.I. of this service bulletin to the Weight and Balance Manual. Under ‘Description of Change’ enter "Service Bulletin 670BA−32−028, Revision A, PART B, incorporated." 

### SERVICE BULLETIN 670BA−32−028

S.B. 670BA−32−028 Page 15 of 17 Dec 22/2010 Revision A, Feb 03/2011(12) When PART B of this service bulletin is completed, make this entry in the applicable logbook(s): "Service Bulletin 670BA−32−028, Revision A, Landing Gear − Brake System − Replacement of Accumulator P/N 0860204001 by P/N 90006691, PART B, incorporated." 

### SERVICE BULLETIN 670BA−32−028

S.B. 670BA−32−028 Page 16 of 17 Dec 22/2010 Revision A, Feb 03/20113. MATERIAL INFORMATION A. Kit Information None. B. Consumable Information For a list of consumables, refer to the different tasks given as references in this service bulletin. C. Special Tools and Equipment For a list of special tools and equipment, refer to the different tasks given as references in this service bulletin. D. Disposition of Parts The table that follows shows the disposition of installed parts on the aircraft (or spares), and the relation of the installed parts (or spares) to the new parts to be installed with this service bulletin.

PRE−SB

PART NUMBER NAME QUANTITY DC POST−SB PART NUMBER NAME

0860204001 Accumulator 2 DIS 90006691 Accumulator Disposition code (DC) : DIS: Discard Part. 

### SERVICE BULLETIN 670BA−32−028

S.B. 670BA−32−028 Page 17 of 17 Dec 22/2010 Revision A, Feb 03/2011THANK YOU FOR ANSWERING THIS EVALUATION FORM UPON COMPLETION OF THIS EVALUATION FORM/COMPLIANCE SHEET, FAX TO 450-476-7300 

### SERVICE BULLETIN EVALUATI ON FORM/COMPLIANCE SHEET (YOUR IDEAS WILL HELP US PROVIDE BETTER BULLETINS)
SERVICE BULLETIN : 670BA-32-028 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