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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

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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 INFORMATION

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

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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 incorporation 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).

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

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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 INFORMATION

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 Assembly2 A DIS 48510 ---5 S

IC Interchangeability Code

A Not interchangeable.

B Removed Part. No direct replacement.

C Conditionally Interchangeable. Installation of superseded part negates the

intent of this service bulletin.

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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 system. 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.

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(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.

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SERVICE BULLETIN 

 HIGHLIGHTS 

Apr 19/12 

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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 48510-32-94 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. 

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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 have 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 

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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. General

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 units,

with aircraft S/Ns and anticipated new cam mechanism installation date.

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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.com
Feb 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