Service Bulletin 215-4414 March 12/10 ATA Ref: 27-10 32-40 Page 1 of 1 

# MODEL CL-215-6B11 (415) REVISION TRANSMITTAL SHEET

FLIGHT CONTROLS / LANDING GEAR SPECIAL INSPECTION OF THE ACCUMULATOR SCREW CAPS P/N 08−8425−014 ON TACTAIR OR YORK ACCUMULATOR P/N 08−8423−010 (MS28700−3)



### Service Bulletin No.: 215−4414 Date of Original Issue: July 9/09 Revision No.: 1 Date of Issue: March 12/10

NOTES: 1. NO RETROACTIVE ACTION IS REQUIRED ON AIRCRAFT MODIFIED TO THE PREVIOUS ISSUE OF THIS SERVICE BULLETIN. 

### 2. This revision supersedes the previous issue of this Service Bulletin. 

### 3. Black bars in the left margin of this Service Bulletin and the details on this Revision Transmittal Sheet refer to changes made since the previous issue.

This Revision is issued to: 1. Add “York” after the name Tactair to make the accumulators “Tactair or York” in the title and throughout the Service Bulletin. 2. Change the revision of Bombardier Aerospace Restriction and/or Special Instruction (RSI) C-3817, from Revision B to B-1.Service Bulletin 215-4414 July 9/09 ATA Ref: 32-40 Page 1 of 14 ATA Ref: 27-10
Rev. 1 March 12/10 

# MODEL CL-215-6B11 (415) SERVICE BULLETIN

FLIGHT CONTROLS / LANDING GEAR SPECIAL INSPECTION OF THE ACCUMULATOR SCREW CAPS P/N 08−8425−014 ON TACTAIR OR YORK ACCUMULATOR P/N 08−8423−010 (MS28700−3) 1. Planning Information A. Compliance The inspections described in this Service Bulletin is mandatory. Time limitation for the visual inspection, PART A of this service Bulletin. For hydraulic accumulator assemblies that have less or equal to 750 flight cycles, the visual inspection as described in this Service Bulletin must be performed before the accumulator reaches 1000 flight cycles, unless otherwise directed by the airworthiness authority of the operator. For hydraulic accumulator assemblies that have more than 750 flight cycles, the visual inspection must be performed within 250 flight cycles upon receiving this Service Bulletin. The visual inspection must be repeated every 250 flight cycles until the first ultrasonic inspection (PART B of this service Bulletin) has been completed at which point the visual inspection may be discontinued. Time limitation for the first ultrasonic inspection, PART B of this service Bulletin. For hydraulic accumulator assemblies that have less or equal to 750 flight cycles, Bombardier Aerospace recommends to perform the ultrasonic inspection as described in this Service Bulletin before the accumulator reaches 1000 flight cycles, unless otherwise directed by the airworthiness authority of the operator. For hydraulic accumulator assemblies that have more than 750 flight cycles, the ultrasonic inspection must be performed within 250 flight cycles upon receiving this Service Bulletin. The ultrasonic inspection must be repeated every 750 flight cycles. NOTE : This Service Bulletin is applicable only to aircraft in the condition as originally delivered by Canadair and/or Bombardier Aerospace or as subsequently modified by Canadair and/or Bombardier Aerospace Service Bulletin(s). Prior to incorporation of this Service Bulletin, the status of any related systems or structural modification(s) introduced by Supplementary Type Approval (STA) or equivalent action must be examined for compatibility with the modifications and test procedures (if applicable) detailed in this Service Bulletin.MODEL CL-215-6B11 (415) SERVICE BULLETIN 

# Bombardier 

# 415

Service Bulletin 215-4414 July 9/09 ATA Ref: 32-40 Page 2 of 14 ATA Ref: 27-10
Rev. 1 March 12/10 B. Approval The technical content of this Service Bulletin has been approved under the authority of the Design Approval Organization No: DAO #93-Q-02. C. Effectivity CL-215-6B11 (415) turboprop aircraft Serial Nos. 2001 to 2990. D. Reason Several accumulator screw cap failures have been reported since 2000 on the Bombardier CRJ-200. Although the Bombardier 415 aircraft uses similar hydraulic accumulators from the same vendor, there have been no reports of accumulator failure from any Bombardier 415 operator. The specific cause of the failure was linked to fatigue in the filet radius of the screw cap shoulder with other failures originating at the thread runout. E. Description This Service Bulletin gives instructions to: − Clean the inspection area on the accumulator screw caps in preparation to perform the visual or ultrasonic inspection − Perform a visual inspection of the screw caps on the four accumulator for indications of cracks − Calibrate the ultrasonic test equipment − Perform the ultrasonic inspection of the suspect accumulator screw caps. NOTE: The inspection requirement is split into two parts; PART A and PART B. − PART A is for the visual inspection of the accumulator screw caps − PART B is for the ultrasonic inspection of the accumulator screw caps.MODEL CL-215-6B11 (415) SERVICE BULLETIN 

# Bombardier 

# 415

Service Bulletin 215-4414 July 9/09 ATA Ref: 32-40 Page 3 of 14 ATA Ref: 27-10
Rev. 1 March 12/10 F. Manpower For PART A We estimate that it will take 1 technician approximately 3 hours to complete this Service Bulletin. For PART B We estimate that it will take 1 technician approximately 4 hours to complete this Service Bulletin. NOTE: Only qualified ultrasonic inspectors certified with a level I, II, or III category per the following specifications are authorized to perform the special inspections described in this Service Bulletin: − MIL−STD−410 − CDN/CGSB-48.9712-95 − COFREND (COnfederation FRançaise pour les Essais Non Destructifs) − CoSAC (Computational Structural Analysis Committee) − ISO 9712 − or equivalent. G. Material Availability This Service Bulletin contains no kit. Tactair or York Calibration Reference Standard (CRS) T11651 is available upon request from Bombardier Aerospace, contact your Amphibious Aircraft Technical Representative for details. H. Tool Availability For PART B − Ultrasonic Flaw Detector, Sonatest Model: UFSD − Potted angle beam contact transducer − For accumulator screw caps P/N 08-8425-104 45 degrees refractive angle in aluminum, 5.0 MHz frequency, contact surface 0.33-inch (8.38 millimeters) by 0.70-inch (17.78 millimeters), 0.57-inch (14.48 millimeters) high Harisonic Model: PAB-0504,45AL − Microdot to BNC coaxial cable − Tactair or York CRS T11651 − Gorptech, Industrial ultrasonic couplant gel (available from Inspectech Ltd.) or equivalent.MODEL CL-215-6B11 (415) SERVICE BULLETIN 

# Bombardier 

# 415

Service Bulletin 215-4414 July 9/09 ATA Ref: 32-40 Page 4 of 14 ATA Ref: 27-10
Rev. 1 March 12/10 I. Weight and Balance Not affected. J. Electrical Load Data Not affected. K. References Bombardier Aerospace Restriction and/or Special Instruction (RSI) C-3817, Revision B-1. L. Publications Affected None. M. Related Service Bulletin None.MODEL CL-215-6B11 (415) SERVICE BULLETIN 

# Bombardier 

# 415

Service Bulletin 215-4414 July 9/09 ATA Ref: 32-40 Page 5 of 14 ATA Ref: 27-10
Rev. 1 March 12/10 2. Accomplishment Instructions NOTE: For this modification, it is assumed that standard maintenance and repair practices will be applied in accordance with applicable Product Support Publications (PSP). A. Preparation WARNING: MAKE SURE THAT PERSONNEL AND EQUIPMENT ARE A SAFE DISTANCE AWAY FROM ALL HYDRAULICALLY OPERATED SYSTEMS BEFORE YOU REMOVE THE ELECTRICAL POWER. IF YOU DO NOT DO THIS, INJURIES TO PERSONNEL AND DAMAGE TO EQUIPMENT CAN OCCUR. (1) Remove the electrical power. Refer to PSP 492, Maintenance Manual, Chapter 24-00-00, ELECTRICAL POWER − MAINTENANCE PRACTICES. (2) Release the hydraulic pressure. Refer to PSP 492, Maintenance Manual, Chapter 29-00-00, HYDRAULIC POWER − MAINTENANCE PRACTICES. (3) Release the nitrogen pressure from the accumulators. Refer to PSP 492, Maintenance Manual. (4) Gain access to the brake, rudder, elevator, and aileron accumulators. Refer to FIGURE 1 for accumulator locations. (5) Clean the entire (360 degrees around) tapered section of the accumulator screw cap with isopropyl alcohol and a clean cloth/rag free of dirt and grease. 3. PART A: Visual Inspection Procedures Refer to the shaded area in FIGURE 2 for the location to be inspected. A. Inspection Procedure (1) With the aid of a light source and an inspection mirror, visually inspect the full circumference of the two accumulator screw caps for evidence of cracks. (2) Acceptance/Rejection Criteria (a) If no crack is found, the accumulator can be returned to service. Refer to Chapters 27 and 32 of PSP 492. 1 Go to Section 6. RECORDING and record the incorporation of PART A of this Service Bulletin. (b) If a crack is found or suspected after the visual inspection, the effected accumulator must be replaced before the next flight. 1 Return the complete accumulator to bombardier Aerospace for further investigation OR: 2 Perform an ultrasonic inspection in accordance with PART B of this Service Bulletin.MODEL CL-215-6B11 (415) SERVICE BULLETIN 

# Bombardier 

# 415

Service Bulletin 215-4414 July 9/09 ATA Ref: 32-40 Page 6 of 14 ATA Ref: 27-10
Rev. 1 March 12/10 0 FIGURE 1 BRAKE ACCUMULATOR

AILERON ACCUMULATORMODEL CL-215-6B11 (415) SERVICE BULLETIN 

# Bombardier 

# 415

Service Bulletin 215-4414 July 9/09 ATA Ref: 32-40 Page 7 of 14 ATA Ref: 27-10
Rev. 1 March 12/10 HIGH PRESSURE GAUGE

0 FIGURE 1 ELEVATOR ACCUMULATOR
RUDDER ACCUMULATOR

AIR (HIGH PRESSURE CHARGING) VALVE ACCUMULATOR SCREW CAP ACCUMULATOR SCREW CAPMODEL CL-215-6B11 (415) SERVICE BULLETIN 

# Bombardier 

# 415

Service Bulletin 215-4414 July 9/09 ATA Ref: 32-40 Page 8 of 14 ATA Ref: 27-10
Rev. 1 March 12/10 POTENTIAL CRACK LOCATION FIGURE 2 CLEAN ENTIRE TAPERED SECTION (SHADED) ON SCREW CAPS WHERE TRANSDUCER WILL BE PLACED FOR SCANNING, APPLY SOLVENT TO THIS AREA 1

NOTE Clean entire tapered section (shaded) on screw caps where transducer will be placed for scanning, apply solvent to this area.
EXTERNAL SHOULDER

POTENTIAL CRACK AT INTERNAL SHOULDER 1 ACCUMULATOR SCREW CAPMODEL CL-215-6B11 (415) SERVICE BULLETIN 

# Bombardier 

# 415

Service Bulletin 215-4414 July 9/09 ATA Ref: 32-40 Page 9 of 14 ATA Ref: 27-10
Rev. 1 March 12/10 4. PART B: Ultrasonic Inspection Procedure NOTE: Tactair or York CRS T11651 is available upon request from Bombardier Aerospace, contact your Amphibious Aircraft Technical Representative for details. Refer to the shaded area in FIGURE 2 for the location to be inspected. A. Equipment Calibration (1) If not already accomplished do the two steps that follow: WARNING: MAKE SURE THAT PERSONNEL AND EQUIPMENT ARE A SAFE DISTANCE AWAY FROM ALL HYDRAULICALLY OPERATED SYSTEMS BEFORE YOU REMOVE THE ELECTRICAL POWER. IF YOU DO NOT DO THIS, INJURIES TO PERSONNEL AND DAMAGE TO EQUIPMENT CAN OCCUR. (a) Remove the electrical power. Refer to PSP 492, Maintenance Manual, Chapter 24-00-00, ELECTRICAL POWER − MAINTENANCE PRACTICES. (b) Release the hydraulic pressure. Refer to PSP 492, Maintenance Manual, Chapter 29-00-00, HYDRAULIC POWER − MAINTENANCE PRACTICES. (c) Release the nitrogen pressure from the accumulators. Refer to PSP 492, Maintenance Manual. Refer to FIGUREs 3, 4, and 5. (2) Remove the suspected accumulator from the aircraft. Refer to PSP 492, Maintenance Manual, Chapter 27 and/or Chapter 32 for accumulator removal procedures. (3) Attach the angle beam transducer (45°angle) to coaxial cable and connect the cable to the ultrasonic instrument. (4) Set the ultrasonic instrument to PULSE-ECHO test mode and 5 MHz test frequency. (5) Apply an even coat of couplant gel on the tapered surface of the CRS. (6) Place the transducer firmly to the tapered section on the CRS such that the sound beam is directed towards the internal shoulder of the screw cap. (7) Manipulate the transducer to obtain a maximized amplitude signal from the EDM notch A (NA) and adjust the instrument GAIN control to set the signal to 80% Full Screen Height (FSH). (8) Adjust and position the leading edge of the notch signal at 50% of the horizontal baseline and the signal from the external shoulder at approximately 90% for the CRS T11651. Refer to Figures 4.MODEL CL-215-6B11 (415) SERVICE BULLETIN 

# Bombardier 

# 415

Service Bulletin 215-4414 July 9/09 ATA Ref: 32-40 Page 10 of 14 ATA Ref: 27-10
Rev. 1 March 12/10 B. Inspection Procedure Refer to FIGURE 2 and 5. (1) Apply an even coat of couplant gel on the tapered surface on the accumulator screw cap to be inspected. (2) Place the transducer firmly to the tapered section on the screw cap such that the sound beam is directed towards the internal shoulder of the screw cap. (3) Manipulate the transducer towards and away from the shoulder with a slight swiveling motion. (4) Inspect the entire 360 degrees around the screw cap for cracks. 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 is cause for further evaluation. (2) Verify and make sure that the indication is not from the external shoulder i.e. the transducer moved too much forward on to the edge or the baseline has shifted accidentally. (3) If the indication is a crack, determine the approximate length of the crack by scanning it in both directions from the peak signal until the signal has dropped to 40 % FSH and mark the centre point of the transducer. The circumferential crack length is the distance between the two points. D. Acceptance or Rejection Criteria (1) All distinct indications with an amplitude signal of 60% FSH or greater appearing at approximately 50% of the horizontal baseline is classified as a crack indication and is cause for rejection. (2) Record and report the results of the ultrasonic inspection to your Amphibious Aircraft Technical Representative.MODEL CL-215-6B11 (415) SERVICE BULLETIN 

# Bombardier 

# 415

Service Bulletin 215-4414 July 9/09 ATA Ref: 32-40 Page 11 of 14 ATA Ref: 27-10
Rev. 1 March 12/10 5. Installation If an accumulator was remove for an ultrasonic inspection and determined to be serviceable or a new accumulator is required, refer to PSP 492, Maintenance Manual, Chapter 32 for installation and test procedures for the break accumulators and Chapter 27 for installation and test procedures for the rudder, elevator, or aileron accumulators. 6. Recording When this Service Bulletin is completed, make the entry in the aircraft log book and send back the attached Incorporation Notice to Amphibious Aircraft Technical Publications. 7. Material Information This Service Bulletin contains no kit. Tactair or York CRS T11651 is available upon request from Bombardier Aerospace, contact your Amphibious Aircraft Technical Representative for details.MODEL CL-215-6B11 (415) SERVICE BULLETIN 

# Bombardier 

# 415

Service Bulletin 215-4414 July 9/09 ATA Ref: 32-40 Page 12 of 14 ATA Ref: 27-10
Rev. 1 March 12/10 TACTAIR OR YORK CALIBRATION REFERENCE STANDARD DETAILS (T11651) FIGURE 3 NOTCH B R 0.080

45 o

45 o NOTCH A R 0.050

NOTCH C R 0.121 3/16 MAX

1.127

1.093 1.524 1.127

1.098 3X 0.0055 MAXMODEL CL-215-6B11 (415) SERVICE BULLETIN 

# Bombardier 

# 415

Service Bulletin 215-4414 July 9/09 ATA Ref: 32-40 Page 13 of 14 ATA Ref: 27-10
Rev. 1 March 12/10 100%

50%

0 50 100 IP

EES

100%

50%

0 50 100 IP EES IP = INITIAL PULSE EES = ECHO FROM EXTERNAL SHOULDER ENA = ECHO FROM NOTCH A TRANSDUCER PLACEMENT EXTERNAL SHOULDER

CRT DISPLAY CALIBRATION AND FAMILIARIZATION (T11651) FIGURE 4 INTERNAL SHOULDER 0.25 INCH REF TRANSDUCER SOUND EXIT POINT

EDM NOTCH A

CRS T11651 END OF TAPERED ENAMODEL CL-215-6B11 (415) SERVICE BULLETIN 

# Bombardier 

# 415

Service Bulletin 215-4414 July 9/09 ATA Ref: 32-40 Page 14 of 14 ATA Ref: 27-10
Rev. 1 March 12/10 TRANSDUCER PLACEMENT AND SCANNING MOVEMENT FIGURE 5 EXTERNAL SHOULDER

TRANSDUCER PLACEMENT AND SCANNING MOVEMENT POTENTIAL CRACK AT INTERNAL SHOULDER

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