Tx Ltr SB 84 ---32 ---100 Page 1 of 2 Revision ‘A’ 30 Aug 2012 JR DHC ---8 (DASH 8) SERVICE BULLETIN 84 ---32 ---100 Landing Gear --- MLG --- Emergency Extension System --- Installation of new Cam Mechanism Assembly 48510 ---5 --- ModSum 4 ---113765 This page transmits Revision ‘A’ of Service Bulletin 84 ---32 ---100, pages 1 thru 6, dated: 30 Aug 2012 This service bulletin is re ---issued in its entirety for the reasons that follow: --- the Effectivity section has been revised --- the References section is revised to convey the latest revision of the service bulletin and engineering documentation The Compliance in the previous issue of this service bulletin is not affected by this revision. No additional rework to the aircraft is introduced by this revision. Remove Service Bulletin 84 ---32 ---100 initial issue dated: 15 Aug 2012 and replace with attached. Previous issues of Service Bulletin 84 ---32 ---100: Initial issue --- Pages 1 thru 6 dated: 15 Aug 2012

### SERVICE BULLETIN 84 ---32 ---100

Tx Ltr SB 84 ---32 ---100 Page 2 of 2 Revision ‘A’ 30 Aug 2012 JR 

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S.B. 84 ---32 ---100 Page 1 of 6 15 Aug 2012 Revision ‘A’ 30 Aug 2012 JR 

# SERVICE BULLETIN Customer Support
ATA SYSTEM: 3211 NUMBER: 84 ---32 ---100

SUBJECT: Landing Gear --- MLG --- Emergency Extension System --- Installation of new Cam Mechanism Assembly 48510 ---5 --- ModSum 4 ---113765

1. PLANNING INFORMA TION A. Effectivity Aircraft Affected: In ---Service: DHC ---8 Aircraft Models 401 and 402 Serial Numbers 4001, 4003 thru 4418, 4422 and 4423. Production: ModSum 4 ---113765 will be installed before delivery on applicable DHC ---8 Aircraft at Serial Number 4419 thru 4421, 4424 and subsequent.
NOTE: The instructions in this service bulletin are only applicable to the systems and parts installed at the time of delivery on the aircraft or as changed by Bombardier Aerospace Service Bulletin(s). Before you do this bulletin, examine all STC or equivalent action changes to make sure this bulletin can be completed. Spares Affected: The following is a list of spares affected by this change. Review spares and procurement systems to determine the existence of any listed parts. See Paragraph 2.D., Existing Parts Accountability, for disposition.

Part Number Description 48510 ---1/ ---3 Cam Mechanism Assembly

### SERVICE BULLETIN 84 ---32 ---100

S.B. 84 ---32 ---100 Page 2 of 6 15 Aug 2012 Revision ‘A’ 30 Aug 2012 JR B. Reason Problem: There have been instances of cam mechanism assembly input lever fractures. In these instances, the MLG door would not open at line check. Cause: Investigation revealed mechanical swelling of the lined bushings on the input and cam follower lever shafts, increasing the force required to move the lever. A contributing factor may be cold temperatures combined with moisture ingress. Solution: The new cam mechanism assembly incorporates new sealed roller bearings in place of the lined bushings, and grease in the cavity between the new bearings. C. Description The procedures in this service bulletin give the instructions to do the tasks that follow: --- aircraft is put into standard configuration for maintenance --- aircraft electrical power is removed --- the nose landing gear lock is engaged --- the main landing gear lock pins are installed thru each main gear and main gear door mechanism --- MLG alternate extension system cam mechanism assemblies are replaced. --- rigging of the alternate extension MLG cables is done --- a test of the MLG alternate release system is done --- close out.

NOTE: Before incorporating this service bulletin operators are to contact Goodrich Landing Gear to determine availability of Cam Mechanism Assembly 48510 ---5. Refer to Goodrich Service Bulletin 48510 ---32 ---94 R1 for further details. D. Compliance Bombardier Inc. recommends incorpora tion of ModSum 4 ---113765 at the earliest opportunity unless otherwise directed by the operator’s airworthiness authority. E. Approval The technical content of this service bulletin has been approved under the authority of the Transport Canada Civil Aviation (TCCA) Design Approval Organization No: DAO #93 ---Q ---02. This service bulletin does not affect Airworthiness Limitations (AWLs) or Damage Tolerance Inspections (DTIs).

### SERVICE BULLETIN 84 ---32 ---100

S.B. 84 ---32 ---100 Page 3 of 6 15 Aug 2012 Revision ‘A’ 30 Aug 2012 JR F. Manpower It will take an estimated 4.5 man ---hours to complete this service bulletin. The breakdown of the man ---hours is shown in the table that follows: TASK MAN ---HOURS Job Set ---Up 0.25 Procedure 3.00 Test / RTS 1.00 Close ---Out 0.25 For any on---site labor assistance, please speak with a Fleet Services representative for a quote. The Fleet Services group can be contacted via the Q Series Technical Help Desk by telephone at 416---375---4000 or email at: thd.qseries@aero.bombardier.com G. Material --- Price and Availability Refer to Goodrich Service Bulletin 48510 ---32 ---94 R1. H. Tooling --- Price and Availability None I. Weight and Balance None
J. Electrical Load Data Not affected
K. Publications Affected Dash 8 Illustrated Parts Catalogue PSM 1 ---84 ---4

.................... ModSums Manual PSM 1 ---84 ---12

.................................. Maintenance Requirement Manual PSM 1 ---84 ---7

....................

### SERVICE BULLETIN 84 ---32 ---100

S.B. 84 ---32 ---100 Page 4 of 6 15 Aug 2012 Revision ‘A’ 30 Aug 2012 JR L. References The initial issue of this service bulletin was prepared to the engineering drawings and related data that follows: ModSum 4 ---113765 Rev. ‘D’ PCA 43597 Revision 0 (for internal reference only) Goodrich Service Bulletin 48510 ---32 ---94 R1 dated: Apr 19/12 2. MATERIAL INFORMA TION A. Parts Required Per Aircraft (1) Detailed Parts List: Quantity Per Aircraft Part Number Description Remarks

2 48510 ---5 Cam Mechanism Assembly Supplied by Goodrich B. Parts Required to Modify Spares None C. Special Tools and Equipment Required None D. Existing Parts Accountability The following parts may be affected by this service bulletin. Indented parts are components of the next higher assembly. The quantity (Qty.) column lists the quantity that may be affected per aircraft for non ---indented parts and the quantity per next higher assembly for indented parts. Existing Part Number Description Qty. IC DC New Part Number PNC 48510 ---1/ ---3 Cam Mechanism Assembly 2 A DIS 48510 ---5 S IC Interchangeability Code A Not interchangeable. B Removed Part. No direct replacement. C Conditionally Interchangeable. Inst allation of superseded part negates the intent of this service bulletin.

### SERVICE BULLETIN 84 ---32 ---100

S.B. 84 ---32 ---100 Page 5 of 6 15 Aug 2012 Revision ‘A’ 30 Aug 2012 JR DC Disposition DIS Discard Part. MUI Multiple Usage Item: Return to stock if serviceable. RWK Rework existing part in accordance with this service bulletin. RWI Rework existing part per ..... SAL Salvage. Return to operator’s stores for salvage consideration. PNC Part Number Code N No equivalent Bombardier Inc. part number for reworked part. Indicate on part that this service bulletin has been accomplished. R Part number after rework. S Superseding or equivalent part number. X Reworked part and superseding part are functionally and physically equivalent but not identical. 3. ACCOMPLISHMENT INSTRUCTIONS A. Job Set ---Up

WARNING: YOU MUST INSTALL THE LOCKPINS ON THE MAIN LANDING GEAR. MAKE SURE YOU ENGAGE THE NOSE GEAR LOCK. IF YOU DO NOT DO THIS, THE LANDING GEAR CAN ACCIDENTALLY RETRACT. THIS CAN CAUSE INJURIES TO PERSONS AND DAMAGE TO THE EQUIPMENT. WARNING: YOU MUST INSTALL THE LOCKPINS IN THE DOOR MECHANISMS OF THE MLG AND NLG. THE DOOR MECHANISMS CAN ACCIDENTALLY CLOSE THE LANDING GEAR DOORS. THIS CAN CAUSE INJURIES TO PERSONS AND DAMAGE TO THE EQUIPMENT. (1) Placard and select all aircraft electrical power to OFF. Obey all relevant WARNINGS and CAUTIONS (refer to AMM TASK’S 24 ---00 ---00 ---861 ---802 and 24 ---00 ---00 ---910 ---801). (2) Make sure that lock pins are installed through each main gear and main gear door mechanism. (3) Make sure the nose gear ground lock is engaged. (4) Set up the work platforms or ladders as required to gain access to the main landing gear alternate extension sys tem. Make sure the work platforms or ladders are electrically grounded. B. Procedure (1) Remove existing Cam Mechanism Assembly 48510 ---1 or ---3. Refer to Maintenance Manual TASK 32 ---34 ---26 ---000 ---801.

### SERVICE BULLETIN 84 ---32 ---100

S.B. 84 ---32 ---100 Page 6 of 6 15 Aug 2012 Revision ‘A’ 30 Aug 2012 JR (2) Install new Cam Mechanism Assembly 48510 ---5. Refer to Maintenance Manual TASK 32 ---34 ---26 ---400 ---801. (3) Do the rigging of the alternate extension MLG cables. Refer to Maintenance Manual TASK 32 ---34 ---16 ---830 ---802. (4) Do a test of the MLG alternate release system as per Maintenance Manual TASK 32 ---34 ---16 ---830 ---802. C. Close Out (1) Remove all tools and equipment from the work area. (2) On incorporation of this ModSum, make an entry that conforms to local regulatory requirements in the applicable logbook(s). Enter component serial numbers if applicable. Enter this ModSum number only after complete and functional incorporation of all work defined in this service bulletin. 1

# 48510 - 32 - 94 R1



# SERVICE BULLETIN

HIGHLIGHTS Apr 19/12 Page 1 of 1 THESE COMMODITIES, SOFTWARE OR TECHNOLOGY WERE EXPORTED/RE

- EXPORTED IN ACCORDANCE WITH U.S. EXPORT ADMINISTRATION REGULATION. DIVERSION CONTRARY TO U.S. LAW IS PROHIBITED. DASH 8 Q400 MLG ALTERNATE EXTENSION SYSTEM

– NEW CAM MECHANISM ASSEMBLY PN 48510-5

REVISION NO.1
–

April 19, 2012

Service Bulletin 4 8510

- 32

- 94 R1 supersedes Service Bulletin 48510

- 32

- 94 dated Dec 2/11 and is re -issued in its entirety to reflect the changes listed below. The compliance in the previous issue of this Service Bulletin is not affected by this revision. No additional rework is introduced by this revision. Please destroy all copies of SB 48510

- 32

- 94 dated Dec 2/11.

Page/Para Change
Page 1, Section I, Para1, Para 3, Para 4 Effectivity and Part number revised. Reason revised to give additional information on 46510-3 assembly. Page 2, Section I, Para 11 Reference added. Page 2, Section II, Para 1 Material cost and Availability updated.

# 48510 - 32 - 94 R1



# SERVICE BULLETIN

Apr 19/12 Page 1 of 2 THESE COMMODITIES, SOFTW ARE OR TECHNOLOGY W ERE EXPORTED/RE -EXPORTED IN ACCORDANCE WITH U.S. EXPORT ADMINISTRATION REGULATION. DIVERSION CONTRARY TO U.S. LAW IS PROHIBITED. Reference Goodrich CMM for proprietary information DASH 8 Q400 MLG ALTERNATE EXTENSION SYSTEM

– NEW CAM MECHANISM ASSEMBLY PN 48510-5

------------------------------------------------------------------------------------------------------------------------------------------ SECTION I - PLANNING INFORMATION 1. EFFECTIVITY All MLG Alternate Extension System Cam Mechanism Assemblies PN 48510-1/-3. 2

. CONCURRENT REQUIREMENTS NA 3. REASON There ha ve been instances of cam mechanism assembly input lever fractures. In these instances, the MLG door would not open at line check. Investigation revealed mechanical swelling of the lined bushings on the input and cam follower lever shafts, increasing the force required to move the lever. A contributing factor may be cold temperatures combined with moisture ingress in the cavity between the shaft bushings. Cam mechanism assembly 48510 -3 has sealed 51200 steel roller bearings in place of the lined bushings, and grease per MIL- PRF

- 81322 in the cavity between the bearings. The new cam mechanism assembly 48510 -5 incorporates CRES roller bearings and grease per MIL- PRF -23827 in the cavity between the new bearings. 4. DESCRIPTION The PN 48510-1/-3 cam mechanism assembly is replaced by a new 48510-5 cam mechanism assembly. 5. COMPLIANCE Goodrich Landing Gear in concurrence with the aircraft manufacturer recommends incorporation of this bulletin at operator ’ s earliest convenience

. 6. APPROVAL This bulletin contains no modification information that revises approved configurations, and therefore does not require governmental or other regulatory approval

. The technical content of this Service Bulletin has been reviewed and accepted by Bombardier Aerospace. 7. MANPOWER NA 8. TOOLING NA 9. WEIGHT AND BALANCE NA 10. ELECTRICAL LOAD DATA NA

# 48510 - 32 - 94 R1 Goodrich Landing Gear Division Goodrich Aerospace Canada Ltd.

Apr 19/12 Page 2 of 2 Reference Goodrich CMM for proprietary information 11. REFERENCES Goodrich Reference Modification Summary Package (MODSUM) 4N113765 Goodrich Landing Gear Service Information Letter (SIL) 02121- 32

- 53 12. OTHER PUBLICATIONS AFFECTED NA

---------------------------------------------------------------------------------------------------------------------------------------- SECTION II
– MATERIAL INFORMATION 1. MATERIAL COST AND AVAILABILITY A. Material Cost and Availability Refer to Goodrich Landing Gear Service Information Letter (SIL 02121- 32 -53) for material cost and availability related to this Service Bulletin. Parts are available from: Goodrich Landing Gear Division, 1400 South Service Rd, Oakville, ON, Canada L6L 5Y7 Phone: 905- 827

- 7777 Fax: 905- 825

- 1583 Att: Warranty Administrator

----------------------------------------------------------------------------------------------------------------------------------------

SECTION III - ACCOMPLISHMENT INSTRUCTIONS 1. Gen e ral A. Contact Goodrich Landing Gear at coordinates detailed in SECTION II to determine availability. B. Goodrich Landing Gear will request a no charge purchase order for total number of unit s, with aircraft S/Ns and anticipated new cam mechanism installation date.Jan 2009 SERVICE BULLETIN (SB) --- RECORD OF INCORPORATION --- Q SERIES DASH 8 AIRCRAFT To: CMDB Focal Facsimile: (1) 416 375 4538 E --mail: cmdb.requests@aero.bombardier.com
From: Company: Phone: Extn: Facsimile: Date:

E --mail: The data that you provide below will help us record the incorporation of this ModSum and the aircraft effectivity in the maintenance manual. Operator: Service Bulletin:

__________________ Revision:

_________ Aircraft Serial Number: Model Number: Date Bulletin Completed: Aircraft Serial Number: Model Number: Date Bulletin Completed: Aircraft Serial Number: Model Number: Date Bulletin Completed: Aircraft Serial Number: Model Number: Date Bulletin Completed: Aircraft Serial Number: Model Number: Date Bulletin Completed: Aircraft Serial Number: Model Number: Date Bulletin Completed: Aircraft Serial Number: Model Number: Date Bulletin Completed: Aircraft Serial Number: Model Number: Date Bulletin Completed: Aircraft Serial Number: Model Number: Date Bulletin Completed: Aircraft Serial Number: Model Number: Date Bulletin Completed: Aircraft Serial Number: Model Number: Date Bulletin Completed: Aircraft Serial Number: Model Number: Date Bulletin Completed: 

## Fax this sheet to (1) 416 375 4538 or Email PDF to: 

# cmdb.requests@aero.bombardier.comFeb 2009 SERVICE BULLETIN (SB) --- COMMENT SHEET --- Q SERIES DASH 8 AIRCRAFT

To: SB Focal (Toronto), Bombardier Aerospace Commercial Aircraft Phone: (1) 416 375 4078 Facsimile: (1) 416 375 4538 E --mail: syed.rizvi@aero.bombardier.com
From: Company: Phone: Extn: Facsimile: Date:

E --mail: Select appropriate box(es) and add comments or suggestions you would like us to know that may enhance the quality of our service bulletins. Service Bulletin: Revision: ModSum: 1. PLANNING INFORMATION V Effectivity V Reason V Description V Compliance V Approval V Manpower V Material V Weight and Balance V Electrical Load V Tooling V References V Publications Affected
2. MATERIAL INFORMATION V Kit Content V Special Tools/Equipment V Parts to Modify Spares V Consumables V Disposition of Existing Parts V Other
3. ACCOMPLISHMENT INSTRUCTIONS V Job Set ---Up V Procedure V Close---Out V Test V Illustration(s) V Other 4. COMMENTS, REMARKS, SUGGESTIONS



## Fax this sheet to (1) 416 375 4538 or Email PDF to: syed.rizvi@aero.bombardier.com