Hydraulic Power − Hydraulic System No. 3 − Inspection of the System

Accumulator Screw−Caps

These pages transmit:

Revision B of Alert Service Bulletin A670BA−29−012,

pages 1 thru 20, dated Dec 22/2010.

and

Revision A of Appendix A

pages A1 thru A9, dated Jul 27/2010.

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:

Remove aircraft serial numbers 10302 thru 10999, 15233, 15234, 15239, and

15259 thru 15990 from the effectivity of the service bulletin.

Add a note in Compliance paragraph 1.D.

Add Bombardier Regional Jet Series All Operator Message (AOM), No. 614,

Parker Service Information Letter 900097−29−226, and to change Parker

Service Bulletin 900097−1−29−392 Revision 1 for Revision 2 in References

paragraph 1.K.

Revised Accomplishment Instructions, paragraph 2., to:

Change task AMM 29−12−11−720−801 for AMM 29−12−11−720−802.

ALERT SERVICE BULLETIN A670BA−29−012

S.B. A670BA−29−012

Page 1 of 2

Dec 22/2010

SERVICE BULLETIN

REVISION TRANSMITTAL SHEET

CL−600−2C10, CL−600−2D15, CL−600−2D24 and CL−600−2E25

CANADAIR REGIONAL JET (CRJ) AIRCRAFT

SUBJECT:
This revision also includes small editorial changes that do not have an effect on the

technical content.

Document Instructions:

Discard the copy of Alert Service Bulletin A670BA−29−012, Revision A, dated Jul

27/2010. Replace with the copy attached.

Service Bulletin History:

Initial issue, dated Mar 13/2008.

Revision A, dated Jul 27/2010.

ALERT SERVICE BULLETIN A670BA−29−012

S.B. A670BA−29−012

Page 2 of 2

Dec 22/2010

REVISION TRANSMITTAL SHEET
Hydraulic Power − Hydraulic System No. 3 − Inspection of the System

Accumulator Screw−Caps

1. PLANNING INFORMATION

A. Effectivity

(1) Aircraft Affected:

Service Bulletin: CL−600−2C10 Canadair Regional Jet (CRJ)

Aircraft Serial Numbers 10003 thru 10301.

Production: There is no production effectivity.

Service Bulletin: CL−600−2D15 Canadair Regional Jet (CRJ) and

CL−600−2D24 Canadair Regional Jet (CRJ)

Aircraft Serial Numbers 15001 thru 15232, 15235

thru 15238, and 15240 thru 15258.

Production: There is no production effectivity.

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 Aerospace Service Bulletin. Before you

do this bulletin, examine all STC, STA or equivalent action changes

to make sure this bulletin can be completed.

ATA SYSTEM: 29−11 NUMBER: A670BA−29−012

S.B. A670BA−29−012

Page 1 of 20

Mar 13/2008

Revision B, Dec 22/2010

ALERT SERVICE BULLETIN

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 screw−caps of the system No. 3 accumulator to have

cracks in the inner shoulder. This can cause the screw−cap to rupture and

cause damage to the aircraft structure and systems.

(2) Evidence

A screw−cap ruptured and disconnected from the hydraulic side of hydraulic

system No. 1 on a CRJ 200 aircraft.

(3) Objective/Benefit

This service bulletin gives the procedure to do a detailed inspection and an

ultrasonic inspection on the screw−caps of the accumulator of hydraulic

system No. 3. This will prevent damage to the accumulators, aircraft

structure and systems.

C. Description

This service bulletin is divided in two parts: PART A and PART B.

PART A − Detailed Inspection of the System Accumulator Screw−Caps

The access panel for the hydraulic system No. 3 components is opened. The

hydraulic pressure is released from system No. 3. The electrical power is

removed. The circuit breakers are opened. The nitrogen pressure is bled from the

system No. 3 accumulator. A visual inspection is done on both ends of the

system accumulator screw−caps.

The circuit breakers are closed. The servicing of the system accumulator is done.

The access panel for the hydraulic system No. 3 components is closed.

PART B − Ultrasonic Inspection of the System Accumulator Screw−Caps

The access panel for the hydraulic system No. 3 components is opened. The

hydraulic pressure is released from system No. 3. The electrical power is

removed. The circuit breakers are opened. The nitrogen pressure is bled from the

system No. 3 accumulator. The system accumulator is removed. An ultrasonic

inspection is done on the system accumulator screw−caps.

The system accumulator is installed. The circuit breakers are closed. If

necessary, hydraulic system No.3 is filled. The servicing of the system

accumulator is done. The nitrogen leak test is done. The hydraulic system is

bled. The access panel for the hydraulic system No. 3 components is closed.

ALERT SERVICE BULLETIN A670BA−29−012

S.B. A670BA−29−012

Page 2 of 20

Mar 13/2008

Revision B, Dec 22/2010
D. Compliance

Alert Service Bulletin.

NOTE: It is not necessary to do this service bulletin when Service Bulletin

670BA−29−015, Hydraulic Power − Hydraulic System No. 3 −

Replacement of Accumulator P/N 900097–1 by P/N 900122–1, is done.

Bombardier Aerospace recommends that this service bulletin be done as shown

in the table below, unless otherwise directed by the airworthiness authority of the

operator:

NOTE: The letter ‘M’ added at the end of the serial number of accumulators P/N

900097−1 identifies that the new screw−caps were installed as shown in

Parker Service Bulletin 900097−1−29−392.

ALERT SERVICE BULLETIN A670BA−29−012

S.B. A670BA−29−012

Page 3 of 20

Mar 13/2008

Revision B, Dec 22/2010
APPLICABLE COMPLIANCE

INSPECTION RESULTS ACTION

For hydraulic

system No. 3:

Accumulators P/N

900097−1 with

serial numbers

without letter ‘M’

at the end (For

the list of serial

numbers see

TABLE 1 and the

note below).

For accumulators that

have 4500 flight cycles

or less, it is necessary

to do PART A of this

service bulletin before

accumulators have 5000

flight cycles.

If a crack is

found during

the detailed

inspection

(PART A), it

is necessary

to replace

the

accumulator

before next

flight.

The crack

must be

identified by

an ultrasonic

inspection

described in

PART B.

It is necessary

to repeat the

detailed

inspection

(PART A)

every 500 flight

cycles from the

initial

inspection.

Or

It is not

necessary to

do or repeat

PART A if

PART B is

done.

For accumulators that

have more than 4500

flight cycles, it is

necessary to do PART

A of this service bulletin

no more than 500 flight

cycles from the issue

date on this service

bulletin.

For accumulators that

have 3000 flight cycles

or less, it is necessary

to do PART B of this

service bulletin before

accumulators have 5000

flight cycles.

If a crack is

found during

the

ultrasonic

inspection

(PART B), it

is necessary

to replace

the

accumulator

before next

flight.

It is necessary

to do PART B

of this service

bulletin every

1500 flight

cycles from the

initial PART B

inspection.

For accumulators that

have more than 3000

flight cycles, it is

necessary to do PART

B of this service bulletin

before 2000 flight cycles

from the issue date of

this service bulletin.

For hydraulic

system No. 3:

Accumulators P/N

900097−1 with

serial numbers

with letter ‘M’ at

the end.

It is not necessary to do this service bulletin.

ALERT SERVICE BULLETIN A670BA−29−012

S.B. A670BA−29−012

Page 4 of 20

Mar 13/2008

Revision B, Dec 22/2010
TABLE 1

60207−0001 thru 60207−0008

60207−0010

60207−0013 thru 60207−0020

60207−0022 thru 60207−0026

60207−0029 thru 60207−0039

60207−0041 thru 60207−0045

60207−0047 thru 60207−0052

60207−0054 thru 60207−0056,

60207−0059 thru 60207−0067,

60207−0069 thru 60207−0070,

60207−0073 thru 60207−0080

60207−0082

60207−0084 thru 60207−0088

60207−0090 thru 60207−0097

60207−0101 thru 60207−0105

60207−0107 thru 60207−0114

60207−0116 thru 60207−0118

60207−0120 thru 60207−0122

60207−0124 thru 60207−0126

60207−0128 thru 60207−0134

60207−0138 thru 60207−0147

60207−0149 thru 60207−0163

60207−0165 thru 60207−0180

60207−0182 thru 60207−0204

60207−0206 thru 60207−0224

60207−0226 thru 60207−0233

60207−0235

60207−0237 thru 60207−0243

60207−0245

60207−0247 thru 60207−0249

60207−0251 thru 60207−0257

60207−0259 thru 60207−0261

60207−0263

60207−0265 thru 60207−0266

60207−0269 thru 60207−0273

60207−0275 thru 60207−0297

60207−0299 thru 60207−0309

60207−0311 thru 60207−0315

60207−0317 thru 60207−0319

60207−0321 thru 60207−0326

60207−0328 thru 60207−1002

60207−1005 thru 60207−1011

60207−1016 thru 60207−1019

NOTE: For serial numbers listed in TABLE 2 below, the new screw−caps were

installed by Parker but it is necessary to incorporate Parker Service

Bulletin 900097−1−29−392 to add the letter ‘M’ at the end of the serial

numbers.

ALERT SERVICE BULLETIN A670BA−29−012

S.B. A670BA−29−012

Page 5 of 20

Mar 13/2008

Revision B, Dec 22/2010
TABLE 2

60207−0009

60207−0011

60207−0012

60207−0021

60207−0027

60207−0028

60207−0040

60207−0046

60207−0053

60207−0057

60207−0058

60207−0068

60207−0071

60207−0072

60207−0081

60207−0083A

60207−0089

60207−0098

60207−0099

60207−0100

60207−0106

60207−0115

60207−0119

60207−0123

60207−0127

60207−0135

60207−0136

60207−0137

60207−0148

60207−0164A

60207−0181

60207−0205

60207−0225

60207−0234A

60207−0236

60207−0244

60207−0246

60207−0250

60207−0258

60207−0262

60207−0264

60207−0267

60207−0268

60207−0274

60207−0298

60207−0310

60207−0316

60207−0320

60207−0327

60207−1003

60207−1004

60207−1012

60207−1013

60207−1014

60207−1015

60207–1020

thru

60207–1321

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.

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.

− 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.

ALERT SERVICE BULLETIN A670BA−29−012

S.B. A670BA−29−012

Page 6 of 20

Mar 13/2008

Revision B, Dec 22/2010
− All other activities that are not considered by Bombardier Aerospace 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 − Detailed Inspection of the System Accumulator Screw−Caps

It will take an estimated 3.0 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 0.5

(3) Test 1.0

(4) Job Close−Out 0.5

NOTE: The man−hours for the procedure do not include the hours to replace

damaged parts. If replacement is necessary, add 2.0 hours for the

accumulator.

PART B − Ultrasonic Inspection of the System Accumulator Screw−Caps

It will take an estimated 5.5 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 3.0

(3) Test 1.0

(4) Job Close−Out 0.5

G. Material − Price and Availability

(1) There are no kits for this service bulletin.

(2) Refer to paragraph 3.C. for a list of consumables for this service bulletin.

ALERT SERVICE BULLETIN A670BA−29−012

S.B. A670BA−29−012

Page 7 of 20

Mar 13/2008

Revision B, Dec 22/2010
H. Tooling − Price and Availability

(1) The tool kit in the table that follows is available from Bombardier commercial

aircraft.

NOTE: For a list of the kit contents, refer to paragraph 3.A.

KIT NUMBER NAME

670BA29012K90 NDT Calibration Tool

NOTE: 601R29−030K90 NDT calibration tool can be used as an alternative

tool.

(2) Please send a purchase order to the address below to schedule the kit:

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.

I. Weight and Balance

Not changed.

J. Electrical Load Data

Not changed.

K. References

− Restriction and/or Special Instruction (RSI), C−29−1052−00, Revision B.

− Parker Service Bulletin 900097−1−29−392, Revision 2, dated Sep

30/2010.

− Bombardier Regional Jet Series All Operator Message (AOM), No. 614.

ALERT SERVICE BULLETIN A670BA−29−012

S.B. A670BA−29−012

Page 8 of 20

Mar 13/2008

Revision B, Dec 22/2010
− Parker Service Information Letter 900097−29−226.

− Aircraft Maintenance Manual (AMM), CSP B−001.

− Nondestructive Testing Manual (NDT), CSP B−010.

− For Bombardier Aerospace reference only: PCA 72957.

L. Other Publications Affected

None.

M. Relationship Chart

Not applicable.

ALERT SERVICE BULLETIN A670BA−29−012

S.B. A670BA−29−012

Page 9 of 20

Mar 13/2008

Revision B, Dec 22/2010
2. ACCOMPLISHMENT INSTRUCTIONS

PART A − Detailed Inspection of the System Accumulator Screw−Caps

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 12−12−29−614−801 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 29−00−00−910−801 Hydraulic Safety Precautions

AMM 53−52−32−010−801 Opening of the Hydraulic Lower

Access Panel (195AB)

AMM 53−52−32−410−801 Closing of the Hydraulic Lower

Access Panel (195AB)

(2) Standard Practices Information

REFERENCE DESIGNATION

AMM 51−26−00−110−801 Solvent Cleaning

NDT 51−20−009−210 Visual − Inspection Procedures

(3) Make sure that the aircraft is in standard configuration for maintenance

(AMM 12−00−00−867−801).

ALERT SERVICE BULLETIN A670BA−29−012

S.B. A670BA−29−012

Page 10 of 20

Mar 13/2008

Revision B, Dec 22/2010
Refer to Figure 1.

(4) Open the system accumulator pressure fill point access door (196CR).

(5) Open the hydraulic lower access panel (195AB) (AMM 53−52−32−010−801).

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) Remove the electrical power from the aircraft (AMM 24−00−00−861−802).

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 THE EQUIPMENT.

(8) Obey all the hydraulic safety precautions (AMM 29−00−00−910−801).

(9) Release the hydraulic pressure from hydraulic system No. 3 (AMM

12−00−06−862−804).

(10) Install safety placard “No ground hydraulic power connection of No. 3

hydraulic system” on the pilot control column.

Refer to Figure 2.

WARNING: USE PROTECTIVE GLOVES TO CAREFULLY LOOSEN THE

VALVE NUT ON THE NITROGEN CHARGING VALVE. KEEP

YOUR HANDS AWAY FROM THE NITROGEN LEAKAGE. THE

NITROGEN LINE IS PRESSURIZED AND CAN CAUSE INJURY.

(11) Release the nitrogen pressure as follows:

(a) Remove the dust cap (4) from the nitrogen charge valve (3).

(b) Carefully loosen the thin nut on the nitrogen charge valve (3).

(c) Let the nitrogen pressure go to zero.

(d) Install the dust cap (4) from the nitrogen charge valve (3).

B. Procedure

Refer to Figures 1 and 2.

ALERT SERVICE BULLETIN A670BA−29−012

S.B. A670BA−29−012

Page 11 of 20

Mar 13/2008

Revision B, Dec 22/2010
WARNING: OBEY ALL CLEANING SAFETY PRECAUTIONS. YOU CAN

CAUSE INJURIES TO PERSONS AND DAMAGE TO THE

EQUIPMENT.

(1) Clean the inspection area section of the system accumulator screw caps (2)

with isopropyl alcohol and a dry, clean cloth.

(2) Do a visual inspection of the two screw−caps (2) of the system accumulator

(1) for an indication of a crack (NDT 51−20−009−210).

(3) If there is an indication of a crack on the system accumulator (1), do PART

B.

C. Job Close−Out

(1) Remove all tools, equipment, and unwanted materials from the work area.

(2) Remove safety placard for “No ground hydraulic power connection of No.3

hydraulic system” on the pilot control column.

(3) Do the servicing of the hydraulic system No.3 accumulator (AMM

12−12−29−614−801).

(4) Close the system accumulator pressure fill point access door (196CR).

(5) Close the hydraulic lower access panel (195AB) (AMM

53−52−32−410−801).

(6) When PART A of this service bulletin is completed, make this entry in the

applicable logbook as follows: "Alert Service Bulletin A670BA−29−012,

Revision B, Hydraulic Power − Hydraulic System No. 3 − Inspection of the

System Accumulator Screw−Caps, PART A incorporated."

PART B − Ultrasonic Inspection of the System Accumulator Screw−Caps

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 Reservoirs

ALERT SERVICE BULLETIN A670BA−29−012

S.B. A670BA−29−012

Page 12 of 20

Mar 13/2008

Revision B, Dec 22/2010
REFERENCE DESIGNATION

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 29−00−00−910−801 Hydraulic Safety Precautions

AMM 29−10−00−870−802 Bleed Hydraulic system No.3

AMM 29−12−11−720−802 Functional Test of the System No.3

Accumulator Pressure Decay Rate

AMM 29−12−11−000−801 Removal of the System No.3

Accumulator

AMM 29−12−11−400−801 Installation of the System No.3

Accumulator

AMM 53−52−32−010−801 Opening of the Hydraulic Lower

Access Panel (195AB)

AMM 53−52−32−410−801 Closing of the Hydraulic Lower

Access Panel (195AB)

(2) Make sure that the aircraft is in standard configuration for maintenance

(AMM 12−00−00−867−801).

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 THE EQUIPMENT.

(3) Obey all the hydraulic safety precautions (AMM 29−00−00−910−801).

(4) Release the hydraulic pressure from hydraulic system No. 3 (AMM

12−00−06−862−804).

(5) Install safety placard “No ground hydraulic power connection of No. 3

hydraulic system” on the pilot control column.

ALERT SERVICE BULLETIN A670BA−29−012

S.B. A670BA−29−012

Page 13 of 20

Mar 13/2008

Revision B, Dec 22/2010
Refer to Figure 1.

(6) Open the system accumulator pressure fill point access door (196CR).

(7) Open the hydraulic lower access panel (195AB) (AMM 53−52−32−010−801).

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.

(8) Obey all the electrical/electronic safety precautions (AMM

24−00−00−910−801).

(9) Remove the electrical power from the aircraft (AMM 24−00−00−861−802).

(10) 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

Refer to Figure 2.

WARNING: USE PROTECTIVE GLOVES TO CAREFULLY LOOSEN THE

VALVE NUT ON THE NITROGEN CHARGING VALVE. KEEP

YOUR HANDS AWAY FROM THE NITROGEN LEAKAGE. THE

NITROGEN LINE IS PRESSURIZED AND CAN CAUSE INJURY.

(11) Release the nitrogen pressure as follows:

(a) Remove the dust cap (4) from the nitrogen charge valve (3).

(b) Carefully loosen the thin nut on the nitrogen charge valve (3).

(c) Let the nitrogen pressure go to zero.

(d) Install the dust cap (4) from the nitrogen charge valve (3).

ALERT SERVICE BULLETIN A670BA−29−012

S.B. A670BA−29−012

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Mar 13/2008

Revision B, Dec 22/2010
(12) Remove the hydraulic system No. 3 accumulator (1) (AMM

29−12−11−000−801).

B. Procedure

(1) Do an ultrasonic inspection on the screw caps (2) of the system accumulator

(1) (Refer to Appendix A).

(2) If there is a crack, do as follows:

(a) Send the system accumulator (1) with the results to:

Bombardier Aerospace

CRJ In Service Engineering

13100 Boulevard Henri Fabre, Mirabel

Quebec, Canada J7N 3C6

C/O ISE group

Dept# 662

(b) Install a new system accumulator (1) (AMM 29−12−11−400−801).

(3) If there is no crack, install the system accumulator (1) (AMM

29−12−11−400−801).

ALERT SERVICE BULLETIN A670BA−29−012

S.B. A670BA−29−012

Page 15 of 20

Mar 13/2008

Revision B, Dec 22/2010
5

4

ACCUMULATOR

3

196CR

ba5009a01.cgm

B

A

B

A

LEGEND

3. Nut.

4. Dust cap.

5. Pressure gauge.

ALERT SERVICE BULLETIN A670BA−29−012

Accumulator Location

Figure 1

S.B. A670BA−29−012

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Mar 13/2008

Revision B, Dec 22/2010
C

D

C

E

1

1

1

2

1

2

E

E

D

LEGEND

1. System accumulator P/N 900097−1.

2. Screw cap.

ba5009a02.cgm

NOTE

1 Inspection area.

ALERT SERVICE BULLETIN A670BA−29−012

Accumulator Inspection Location

Figure 2

S.B. A670BA−29−012

Page 17 of 20

Mar 13/2008

Revision B, Dec 22/2010
C. Job Close−Out

(1) Remove all tools, equipment, and unwanted materials from the work area.

(2) Remove safety placard for “No ground hydraulic power connection of No.3

hydraulic system” on the pilot control column.

(3) Remove the tags and close 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

(4) Replenish the hydraulic system No. 3 reservoir (AMM 12−12−29−611−802).

(5) Do the servicing of the hydraulic system No. 3 accumulator (1) (AMM

12−12−29−614−801).

(6) Bleed hydraulic system No. 3 (AMM 29−10−00−870−802).

(7) Do the functional test for the hydraulic system No. 3 accumulator pressure

decay rate (AMM 29−12−11−720−802).

(8) Close the system accumulator pressure fill point access door (196CR).

(9) Close the hydraulic lower access panel (195AB) (AMM

53−52−32−410−801).

(10) When PART B of this service bulletin is completed, make this entry in the

applicable logbook as follows: "Alert Service Bulletin A670BA−29−012,

Revision B, Hydraulic Power − Hydraulic System No. 3 − Inspection of the

System Accumulator Screw−Caps, PART B incorporated."

ALERT SERVICE BULLETIN A670BA−29−012

S.B. A670BA−29−012

Page 18 of 20

Mar 13/2008

Revision B, Dec 22/2010
3. MATERIAL INFORMATION

A. Kit Information

Kit Content:

KIT 670BA29012K90

PART

NUMBER

QUANTITY NAME ALTERNATE

PART(S)

NOTES

T11651 1 NDT

Calibration

Tool

[1] Refer to paragraph 1.H. for special terms and conditions.

B. Consumable Information

The material that follows is necessary to do this service bulletin and can be ordered

from Bombardier Aerospace Regional Aircraft or purchased directly from industry

sources. If the material is ordered from Bombardier Aerospace Regional Aircraft,

there can be some lead time because of shelf life of the material.

CONSUMABLES

SPECIFICATION QUANTITY NAME REFERENCE

As

necessary

Cloths, cleaning,

low lint

05−001 [1]

TT−I−735 As

necessary

Alcohol,

isopropyl

11−004 [1]

[1] Refer to AMM 51−31−00−992−801.

NOTE: To complete this list of consumables, refer to the different tasks and

Appendix A 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 and Appendix A

given as references in this service bulletin.

ALERT SERVICE BULLETIN A670BA−29−012

S.B. A670BA−29−012

Page 19 of 20

Mar 13/2008

Revision B, Dec 22/2010
D. Disposition of Parts

Not applicable.

ALERT SERVICE BULLETIN A670BA−29−012

S.B. A670BA−29−012

Page 20 of 20

Mar 13/2008

Revision B, Dec 22/2010
 

Mar 13/2008 APPENDIX A

Revision A, Jul 27/2010 Page A1 of A9

PROCEDURE 

The procedure contained in this appendix is given as references in the 

ACCOMPLISHEMENT INSTRUCTION of Service Bulletin A670BA-29-012 
Appendix A 

Mar 13/2008 APPENDIX A

Revision A, Jul 27/2010 Page A2 of A9

Ultrasonic Inspection of the Screw Caps installed on the System Accumulator 

assemblies P/N 900097-1 (Hydraulic System No. 3).

1. General 

A. Function 

Refer to Figure A1. 

This inspection procedure is used to detect the subsurface cracks at the internal 

shoulder of the screw caps (gas and fluid sides) installed on the System 

Accumulator assembly P/N 900097-1 (1). 

B. Reference Information 

For additional data that is necessary to do this inspection, refer to the following 

manuals: 

- Nondestructive Testing Manual (NDTM CSP A-010) Part 1, 51-20-004-270 

A01, General Information; 

- Structural Repair Manual (SRM); 

- Aircraft Maintenance Manual (AMM). 

C. Location 

The inspection area is found in Zone 160 (Refer to AMM 06-20-00-992-801 

A01). The System Accumulator assembly P/N 900097-1 (1) is installed in the Aft 

RHS of the MLG bay. The piston-type accumulator assembly is cylindrical and 

closed with screw caps at each end. 

D. Access

WARNING: OBEY ALL SAFETY PRECAUTIONS WHEN YOU DO 

MAINTENANCE ON OR NEAR ELECTRICAL/ELECTRONIC EQUIPMENT 

AND/OR PRESSURIZED HYDRAULIC SYSTEMS. IF YOU DO NOT OBEY 

THE SAFETY PRECAUTIONS, INJURIES TO PERSONS AND/OR DAMAGE 

TO EQUIPMENT CAN OCCUR. 

(1) Remove the System Accumulator assembly P/N 900097-1 (1). Refer to the 

applicable AMM Tasks for System Accumulator assembly P/N 900097-1 (1) 

Removal/Installation. 

WARNING: OBEY ALL THE SAFETY PRECAUTIONS WHEN YOU USE 

CHLORINATED OR OTHER SOLVENTS TO CLEAN THE WORK SURFACES. 

MAKE SURE THAT THERE IS A SUFFICIENT SUPPLY OF FRESH AIR. USE 

PROTECTIVE CLOTHING AND SAFETY GLASSES. IF THIS IS NOT DONE, 

INJURIES TO PERSONS CAN OCCUR. 
Appendix A 

Mar 13/2008 APPENDIX A

Revision A, Jul 27/2010 Page A3 of A9

(2) Using solvent and a dry clean cloth, clean the entire (360 degrees around) 

tapered section of the screw caps where the transducer is to make contact 

during the inspection (see Figure A1 and Figure A4). Refer to AMM Task 51-26-

00-110-801 for the Solvent Cleaning procedure. 

E. Parts examined in this procedure: 

DESCRIPTION ACCUMULATOR 

PART NUMBER 

VENDOR PART 

NUMBER 

MATERIAL 

Parts examined in this 

procedure: Hydraulic 

System #3 Accumulator 

assembly 

 - Screw Cap 

900097-1 Accumulator : 900097-

1 

Screw cap 

material :7075-

T73 Al Alloy 

2. Tools and Equipment 

A. Use the items that follow, or their equivalent (Refer to the NDTM Part 1, 51-

20-004-270-A01). 

B. NOTE: Equivalent ultrasonic equipment can be used providing that it 

satisfies the requirements of this procedure and is capable of resolving the 

reference notch(es) in the calibration reference standard (CRS) at the 

required level of sensitivity. 

- Ultrasonic flaw detector with A-scan presentation, Sonatest Model: UFDS 

- Potted angle beam contact transducer, 45 deg refractive angle in aluminum, 

5.0 MHz frequency, contact surface 0.33-inch (8.38 mm) by 0.70-inch (17.78 

mm), 0.57-inch (14.48 mm) high. 

Harisonic Model: PAB-0504, 45o AL. 

- Microdot to BNC type coaxial cable. 

- Ultrasound Calibration Reference Standard Tool, similar in geometry as the 

part to be inspected containing several electrical discharge machined (EDM) 

notches (Figure A2). 

Tactair Part Number: T11651 

- Inspectech LTD: Gorptech Industrial Ultrasonic Couplant Gel. 

3. Inspection for Subsurface Cracks on the Screw Cap Inner Shoulder of the System 

Accumulator 

A. Equipment Calibration 

Refer to Figure A2 and Figure A3.
Appendix A 

Mar 13/2008 APPENDIX A

Revision A, Jul 27/2010 Page A4 of A9

NOTE: Make sure that you follow the manufacturer’s instructions when 

operating the test equipment. 

NOTE: Do not allow the ultrasonic couplant to dry on the inspection surface. If 

necessary, add more couplant, to replenish the surface. 

(1) Attach the 45 deg angle beam transducer to coaxial cable and connect the 

cable to the ultrasonic instrument. 

(2) Turn on the power and set the ultrasonic instrument to pulse-echo test mode 

and 5 MHz test frequency. 

(3) Apply a generous and even layer of couplant to the tapered section of the 

calibration reference standard (CRS) T11651. 

(4) Place the transducer firmly on the tapered section on the CRS such that 

sound beam is directed towards the internal shoulder of the screw cap. 

(5) Manipulate the transducer by slightly swiveling and moving it towards and 

away from the internal shoulder to obtain a maximized amplitude signal from 

the 0.050-inch radius notch A (NA). 

(6) Adjust the instrument GAIN (sensitivity) control to set the amplitude signal at 

80% full screen height (FSH). 

(7) Adjust and position the leading edge of the notch signal at 50% of the 

horizontal baseline and the signal from the external shoulder should appear 

at approximately 90% of the horizontal baseline. 

B. Inspection Procedure 

Refer to Figure A1 and Figure A3. 

(1) After carrying out the Equipment Calibration procedure as outlined in the 

previous subsection, apply an even layer of couplant to the tapered section 

of the screw caps to be inspected (both the gas and fluid sides). 

(2) Place the transducer firmly on the tapered section of the screw cap such that 

the sound beam is in the direction of the internal shoulder. 

(3) Manipulate the transducer towards and away from the shoulder with a slight 

swiveling motion. 

(4) Inspect for cracks 360 degrees (full circumference) around the screw cap. 

(5) Repeat step 3.B.(1) through (4) for the other screw cap. 
Appendix A 

Mar 13/2008 APPENDIX A

Revision A, Jul 27/2010 Page A5 of A9

C. Evaluation of Indications 

(1) Any indication with an amplitude signal of 60% FSH or greater at 

approximately 50% of the horizontal baseline limit is considered a suspect 

indication and represents a cause for further evaluation. 

(2) Verify and ensure that the indication is not from the external shoulder, i.e. the 

transducer moved too forward to the edge of the external shoulder or the 

baseline was shifted accidentally. 

(3) If the indication corresponds to a crack, determine the approximate crack 

length by scanning in both directions from the peak signal until the signal has 

dropped to 30% FSH and mark the center point of the transducer. The 

circumferential crack length is the distance between the two points. 

D. Acceptance / Rejection Criteria 

(1) All distinct indications with an amplitude signal of 60% FSH or greater 

appearing at approximately 50% of the horizontal baseline are classified as a 

crack indications and represent causes for rejection. 

(2) Record and report all results. 

4. Close-out Procedure 

A. Refer to close-out section of Alert Service Bulletin A670BA-29-012 PART B.
Appendix A 

Mar 13/2008 APPENDIX A

Revision A, Jul 27/2010 Page A6 of A9 ba5010a01.cgm

A

B

A

1

1

2

1

2

C

C

B

LEGEND

1. System accumulator P/N 900097-1.

2. Screw cap.

NOTE

1 Inspection area.

C

1

System Accumulator Screw Cap Locations 

Figure A1 
Appendix A 

Mar 13/2008 APPENDIX A

Revision A, Jul 27/2010 Page A7 of A9

0.050 in.

(1.27 mm)

DP

NOTCH B

0.080 in.

(2.03 mm)

BOTH SIDES

NOTCH A NOTCH C

0.050 in.

(1.27 mm)

BOTH SIDES

0.050 in.

(1.27 mm)

DP

0.050 in.

(1.27 mm)

DP

0.121 in.

(3.07 mm)

BOTH SIDES

45 DEGREE

45 DEGREE

C

D

E

C D E

A A

B

B

A A

B B

ba5011a01.cgm

Tactair CRS Number T11651 

Figure A2 
Appendix A 

Mar 13/2008 APPENDIX A

Revision A, Jul 27/2010 Page A8 of A9

IP

EES

100%

50%

0 50 100

ENA

IP

EES

IP = INITIAL PULSE

ENA = ECHO FROM NOTCH A

EES = ECHO FROM EXTERNAL SHOULDER

100%

50%

0 50 100

 360° AROUND

TRANSDUCER TAPERED SURFACE

MOVEMENT

EDM NOTCH A

TRANSDUCER

SOUND EXIT POINT

CRS T11651

TRANSDUCER

PLACEMENT

EXTERNAL

SHOULDER

INTERNAL

SHOULDER

0.25 in. (6.35 mm)

END OF TAPERED 

ba5012a01.cgm

Transducer location and CRT Display 

Figure A3 
Appendix A 

Mar 13/2008 APPENDIX A

Revision A, Jul 27/2010 Page A9 of A9

EXTERNAL SHOULDER

POTENTIAL CRACK AT

INTERNAL SHOULDER

ba5013a01.cgm

Potential Crack Location 

Figure A4 
THANK 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-29-012 ISSUE: B

 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