de HAVILLAND 

BOMBARDIER DASHB 

SERVICE BULLETIN 

____ Customer ___________________ _ 

Support 

ATA SYSTEM: 7610 NUMBER: 8-76-33 

BOMBARDIER AEROSPACE REGIONAL AIRCRAFT CONSIDER THIS 

SERVICE BULLETIN TO BE PARTICULARLY SIGNIFICANT AND 

URGES OPERATORS TO PROMPTLY EVALUATE THE CONTENTS 

SUBJECT: Engine Controls- Center Console- Beta Warning Horn 

Microswitch Bracket Improvement - ModSum 80113014 

1. PLANNING INFORMATION 

A. Effectivity 

Aircraft Affected: 

In-Service: 

13 Dec 2012 

DHC-8 Aircraft Models 102, 103, 106, 201 , 202, 301, 311, 

314 and 315 Serial Numbers 003 thru 672 with Beta Warning 

Horn {Mod 8/2852}. Excluding aircraft with option 

CR873CH00003, CR873CH00005, CR873S008112 or 

MS80902206. 

S.B. 8-76-33 

Page 1 of 16 

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SERVICE BULLETIN 8-76-33 

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: 

None 

B. Reason 

Problem: The beta warning horn microswitch function was found to be sensitive to 

center console cover deformation. This could affect correct operation of 

the beta warning horn system. 

Solution: This service bulletin introduces ModSum 80113014. 

The ModSum reworks the center console FWD cover p/n 87610098 by 

replacing the current beta warning horn microswitch bracket p/n 87610428 

with new bracket assy 87610164-003. 

The new bracket is more robust and will be installed lower on the cover to 

avoid sensitivity to cover deflection (see Figure 1 view B). 

C. Description 

The procedures in this service bulletin give the instructions to do the tasks that 

follow: 

- all aircraft electrical power is disconnected 

- the nose landing gear lock is engaged 

- the main landing gear lock pins are installed thru each main gear and main gear 

13 Dec 2012 S.B. 8-76-33 

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SERVICE BULLETIN 8-76-33 

door mechanism 

- certain cover assemblies are removed from the center console 

- rework to the center console includes removal of plate p/n 87610427-101 from 

angle assy 87610428 and removal of angle assy p/n 87610428 from the forward 

cover p/n 87610098 

- open rivet holes in cover p/n 87610098 are plugged 

- new bracket assy p/n 87610164 - 003 is installed to cover p/n 87610098 

- cover assy 87610098 is re-identified as 8Z9662-053 then installed 

- plate p/n 87610427-101 is attached to bracket assy 87610164-003 

- the beta warning horn limit switch is rigged to agree with existing AMM instructions 

- the center console covers previously removed are installed to original positions 

- an operational test of the beta warning horn system is done 

- all tools and equipment are removed from the work area 

- log book entries are made. 

D. Compliance 

Bombardier Inc. recommends incorporation of ModSum 80113014 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 #93-0-02. 

13 Dec 2012 S.B. 8-76-33 

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SERVICE BULLETIN 8-76-33 

F. Manpower 

It will take an estimated 6 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 1.00 

Procedure 3.00 

Test I RTS 1.00 

Close-Out 1.00 

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 

The ModKit listed in the table below is available through the Customer Accounts 

Service Team at Bombardier Aerospace Regional Aircraft division. Operators 

should submit a purchase order specifying aircraft serial number(s) to: 

Bombardier Aerospace 

Customer Accounts Services Team (Mail Stop N11-32) 

123 Garratt Blvd. 

Toronto 

Ontario 

Canada M3K-1 Y5 

Facsimile: (416) 375-3060 

Telephone: (416) 375- 3920 

Kit Number 

8MK4616-003 

13 Dec 2012 

Description 

Center Console - Beta Warning Horn 

Microswitch Bracket - Retrofit Kit 

S.B. 8-76-33 

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H. 

I. 

J. 

K. 

SERVICE BULLETIN 8-76-33 

Tooling - Price and Availability 

None 

Weight and Balance 

None 

Electrical Load Data 

Not affected 

Publications Affected 

Maintenance Manual ................................ PSM 1-8-2, 

PSM 1 - 82-2 and 

PSM 1-83-2 

Dash 8 Parts .................. ...... .... ....... .... PSM 1-8-4, 

PSM 1-82-4 and 

PSM 1-83-4 

Modifications Manual ............................... PSM 1 -813-1 2 

L. References 

The initial issue of this service bulletin was prepared to the engineering drawings 

and related data that follows: 

DRAWING SHEET 

8MK4616 1 

8Z9662 1 

ModSum 80113014 Rev. 'C' 

PCA 07020 Rev 0 (for internal reference only) 

Transport Canada Airworthiness Directive CF- 2012-01 

13 Dec 2012 

REV 

-A 

-8 

S.B. 8-76-33 

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SERVICE BULLETIN 8-76-33 

2. MATERIAL INFORMATION 

A. Parts Required Per Aircraft 

(1) Modification Kit 8MK4616-003 

(2) Detailed Kit Content 

Quantity Per Kit Part Number Description Remarks 

-003 

1 8761 0164-003 BRACKET ASSY 

1 NAS1351 - 3-8P SCREW See NOTE 1 Below 

2 so2oso 17 ADs - as RIVET See NOTE 1 Below 

2 B0205016AD4 -4S RIVET See NOTE 1 Below 

NOTE 1: These items are required to install the kit. These items are not included 

in the kit and must be supplied by the operator. 

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. 

13 Dec 2012 S.B. 8-76-33 

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SERVICE BULLETIN 8-76-33 

Existing New Part 

Part Number Description Qty. JC DC Number PNC 

87610428 Angle Assy 1 A DIS 87610164-003 N 

JC Interchangeability Code 

A Not interchangeable. 

8 Removed Part. No direct replacement. 

C Conditionally Interchangeable. Installation of superseded part negates the 

intent of this service bulletin. 

DC Disposition 

DIS Discard Part. 

MUI Multiple Usage Item: Return to stock if seNiceable. 

RWK Rework existing part in accordance with this seNice bulletin. 

AWl Rework existing part per ..... 

SAL Salvage. Return to operator's stores for salvage consideration. 

PNC Part Number Code 

N New part number 

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. 

13 Dec 2012 S.B. 8 - 76-33 

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SERVICE BULLETIN 8-76-33 

3. ACCOMPLISHMENT INSTRUCTIONS 

A. Job Set-Up 

(1) Placard and select all aircraft electrical power to OFF. Obey all relevant 

WARNINGS and CAUTIONS (refer to Chapters 12 and 24 in applicable AMM). 

(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) Gain access to the center console in the flight deck 

B. Procedure 

{1) Remove and retain the screws and washers that attach the center console 

covers that follow. Keep all hardware (refer to Figure 1 view A) : 

- elevator trim wheel cover 

- power lever cover 

- condition lever cover 

- flap lever cover 

(2) Disconnect plate 87610427 from angle assy 87610428 (refer to Figure 2). 

Do not remove stop shaft p/n 87610088 from plate (p/n 87610427) and from 

center console frames. 

(3) Remove and retain the forward center cover 8761 0098 from the center console 

(refer to flagnote .£.on Figure 2. Retain all hardware for later installation. 

13 Dec 2012 S.B. 8-76-33 

Page 8 of 16 

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SERVICE BULLETIN 8-76-33 

(4) Remove the rivets that attach angle assy p/n 87610428 to cover assy p/n 

87610098. Discard angle assy p/n 87610428 (refer to flag note ffi on Figure 

2). Deburr open rivet holes. Treat bared metal using alodine 1200, 1200S or 

1201 and prime using epoxy chromate primer: 

(5) Plug open rivet holes leftover in cover p/n 8761 0098 with 2 rivets p/n 

B0205016AD4- 4S. Install rivets per SRM Chapters 51-42-05 (refer to flagnote 

.ffi. on Figure 3.) NOTE: It is acceptable to use alterative rivets p/n 

MS20470AD4-4. 

(6) Install bracket assy p/n 8761 0164- 003 on cover p/n 87610098 using 2 rivets p/n 

80205017AD5-8S (refer to Figure 3 flagnote £). Establish bracket assy 

location on the cover based on the location of plate p/n 87610427. Install rivets 

per SRM Chapter 51-42-05. 

(7) Re-identify reworked cover assy 87610098 as 8Z9662-053 using applicable 

instructions in AMM Chapter 20-15-04. 

(8) Install reworked cover assy 829662-053 using previously removed fasteners. 

(refer to flagnote ffi on Figure 4). 

(9) Attach plate p/n 87610427 to the bracket assy 87610164-003 using screw 

NAS1351 - 3- 8P and previously removed washer (refer to flagnote & on 

Figure 4). 

(1 0) Adjust the limit switch to agree with applicable instructions in AMM Chapter 

76-10-13-02 (100/300 series aircraft} or AMM TASK 76-10-13-830-801 

(200 series aircraft} and details shown on Figure 5. 

(11) Move the power levers between the FLT IDLE and MAX REV positions. Make 

sure that 0.100 inch. MIN. clearance exists between detent arm and flange of 

bracket 87610164- 003 (refer to flagnote & on Figure 4) .. 

13 Dec 2012 S.B. 8-76-33 

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SERVICE BULLETIN 8-76-33 

(12) Install the center console covers that follow to original position using saved 

hardware (refer to Figure 1): 

- elevator trim wheel cover 

- power lever cover 

- condition lever cover 

- flap lever cover 

(13) Do an operational test of the beta warning horn system to agree with applicable 

instructions given in AMM Chapter 31 -51 -02 (1 00 I 300 series) or TASK 

31-51-02-710-802~00serie~. 

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. 

13 Dec 2012 S.B. 8-76-33 

Page 10 of 16 

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13 Dec 2012 

SERVICE BULLETIN 8-76-33 

ELEVATOR TRIM 

WHEEL COVER 

\ POWER LEVER 

COVER 

CONDITION LEVER 

FLAP LEVER /

COVER 

--~L COVER 

' . p _.. ~~ :~\ ·~ ~ ........ -- .• ;;' 

OLD BRACKET ,;; , • ' .] ;. · ,' 

NEW BRACKET % 

® 

Beta Warning - Installation 

Figure 1 

0 

. 

L. 

S.B. 8- 76- 33 

Page 11 of 16 

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SERVICE BULLETIN 8-76-33 

& 

(CENTER a::tal..E COVERS I 

REt1JVE & RETAIN 

& 

<PLATE 876104271 

& 

COVER 87610098 REF 

RE11JVE & REWCA< 

SECTION THROUGH CENTRE CONSOLE 

WITH PILOT WARNING HORN 

ACTUATOR INSTALLED 

(VIEW PRIOR TO REWORI<l 

Power Lever in Center Console - Pre Mod Section View 

Figure 2 

13 Dec 2012 S.B. 8-76-33 

Page 12 of 16 

LS 
e 

RIVET 

SERVICE BULLETIN 8-76-33 

0.599 

INCH 

2. t 3 

RIVET £ 

I B0205016AD4-4S 1' _y~ 

! ;J 

/j 

// r-----~ 

~;~...-..~ 

Q 

80205017 AD5 -8S 2.24 COVERASSY 

(87610098) 2 PLCS ill 

(INSTALL FLUSH WITH 

COUNTERSINK HEAD 

INSIDE) 

13 Dec 2012 

BRACKET 

87610164-003 

-053 

Cover Assembly- Rework 

Figure 3 

S.B. 8-76-33 

Page 13 of 16 

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M 

PLATE 

87610427 

SCREW 

NAS1351-3-8P 

CAN960010L WASHER) 

WAS ffi 

COVER ASSY 

p/n 8761 0098 

NOW p/n 

8Z9662-053 

PATH OF DETENT 

ARM 

SERVICE BULLETIN 8-76-33 

A 

<CENTER C0>6QE COVERS l 

-003 

( SECTI ~ Tt-R:LQ-l CENTRE CCNSCl..E J 

Power Lever in Center Console- Post Mod Section View 

Figure 4 

13 Dec 2012 S.B. 8-76-33 

Page 14 of 16 

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13 Dec 2012 

SERVICE BULLETIN 8-76-33 

SWITCH 

SCREW I 

(e) 

Micro Switch Rigging 

Figure 5 

ACTUATOR 

.ARM 

/ 

MINIMUM CLEARANCE 

0.030 m. (0.762 mm) WITH 

PO\"JER LEVERS IN 

FORWARD POWER RANGE 

S.B. 8-76-33 

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SERVICE BULLETIN 8-76-33 

This Page Intentionally Blank. 

13 Dec 2012 S.B. 8-76-33 

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