# Bombardier Service Bulletin 84-24-53

Copy: Revision A ("U.S. DOT/FAA - SB 84-24-53-RA"), 12 pages: PDF https://openairdocs.org/files/sha256/70/9f/709f4ba79a1882751ec022f2379139a77161e47a958d42ada0d6d72431eb305d; text https://openairdocs.org/service-documents/bombardier/sb-84-24-53/file/709f4ba79a18.md. Rights: © Bombardier Inc. Filed by the FAA in regulations.gov docket FAA-2013-1067; AD 2014-20-09 incorporates this document by reference. Not covered by OpenAirDocs’ CC0 dedication.

## Details

- Manufacturer: [Bombardier](https://openairdocs.org/service-documents/bombardier.md)
- Type: Service bulletin (Service Bulletin)
- Number: 84-24-53
- Latest revision known: 84-24-53, Revision B, dated September 10, 2015 (OpenAirDocs)
- Page: https://openairdocs.org/service-documents/bombardier/sb-84-24-53

## ADs that cite it (2) (OpenAirDocs)

Newest first, with the revision each names, as OpenAirDocs read it from the AD's text.

- [AD 2017-17-02](https://openairdocs.org/ad/2017-17-02.md), effective Sep 25, 2017: Revisions A and B
- [AD 2014-20-09](https://openairdocs.org/ad/2014-20-09.md), effective Nov 7, 2014: Revision A

Also cited in [2 proposed ADs](https://openairdocs.org/service-documents/bombardier/sb-84-24-53/proposed.md).

## Text (12 pages)

Rights: © Bombardier Inc. Filed by the FAA in regulations.gov docket FAA-2013-1067; AD 2014-20-09 incorporates this document by reference. Not covered by OpenAirDocs’ CC0 dedication. Each page's text from the PDF; open the PDF at a page with #page=N.

### Page 1

Revision ‘A’ 16 May 2013
DHC-8 (DASH 8)
SERVICE BULLETIN 84-24-53
This page transmits Revision ‘A’ of Service Bulletin 84-24-53, pages 1 thru 8,
dated 16 May 2013.
This service bulletin is re-issued in its entirety for the reasons that follow:
- the Description section revised to include inspection for chafing - PART B
expanded to include repairs per WDM and AMM
- the References section revised to convey the latest revision of the service
bulletin and engineering documentation
- the ACCOMPLISHMENT INSTRUCTIONS - Job Set-Up section revised to
change reference from PSM to AMM, for consistency
- the ACCOMPLISHMENT INSTRUCTIONS - Procedure section revised to
add extra steps
- content revised to change tube to line, for consistency, except for the
illustrations in order to expedite release of this Service Bulletin
- clerical error corrected
- boldfacing removed, where unecessary
The Compliance in the previous issue(s) of this service bulletin is not
affected by this revision. No additional rework to the aircraft is introduced by
this revision.
Remove the initial issue of Service Bulletin 84-24-53 and replace with
attached.
Previous issue(s) of Service Bulletin 84-24-53:
Initial issue - Pages 1 thru 8 dated 11 May 2012

### Page 2

(No text on this page.)

### Page 3

D
S.B. 84-24-53
Page 1 of 8
11 May 2012
Revision ‘A’ 16 May 2013 RR
SERVICE BULLETIN
Customer
Support
ATA SYSTEM: 2400 NUMBER: 84-24-53
BOMBARDIER AEROSPACE REGIONAL AIRCRAFT CONSIDER THIS
SERVICE BULLETIN TO BE PARTICULARLY SIGNIFICANT AND
URGE OPERATORS TO PROMPTLY EVALUATE THE CONTENTS
SUBJECT: Electrical Power - Wiring Installation - Center Fuselage - Special
Inspection and Rectification to En sure the Installation of Clamping
Hardware between AC Power Feeder Cables and Hydraulic Line
1. PLANNING INFORMATION
A. Effectivity
Aircraft Affected:
In-Service: DHC-8 Aircraft Models 401 and 402 Serial Numbers 4001 thru
4347.
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

### Page 4

SERVICE BULLETIN 84-24-53
S.B. 84-24-53
Page 2 of 8
11 May 2012
Revision ‘A’ 16 May 2013 RR
B. Reason
Problem: A line check at the Bombardier ma nufacturing facility has discovered that
the AC power feeder cables and the hydraulic line (tube) of the landing
gear alternate extension installed under floor between station X321.000
and X341.000 on the LHS of the aircraft have not been secured with the
appropriate clamps.
Solution: This service bulletin gives the instructions to do a special inspection and
if necessary rectification to make sure that the clamps between AC power
feeder cables and the hydraulic line are installed to avoid possible chafing.
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 inst alled through each main gear and main
gear door mechanism
- the carpet, the passenger seats and floor path emergency lights between station
X321.000 and X341.000 (left hand side of passenger compartment) are removed
- PART A - INSPECTION - access is gained to the inspection area under the floor
between station X321.000 and X341.000 (left hand side of passenger
compartment).
- the area is inspected for missing clamping hardware and chafing between the AC
power feeder cables and the hydraulic line.
- if the clamps are installed, close out section is done
- if the clamps are not installed, PART B - RECTIFICATION is completed
- PART B - RECTIFICATION - damage to the AC power feeder cables or the hydraulic
line is repaired per Wiring Diagram Manual (WDM) or Aircraft Maintenance Manual
(AMM), respectively. Clamping hardware is installed between the AC power feeder
cables and the hydraulic line.
- the carpet, the passenger seats and floor path emergency lights are re-installed
- close out.

### Page 5

SERVICE BULLETIN 84-24-53
S.B. 84-24-53
Page 3 of 8
11 May 2012
Revision ‘A’ 16 May 2013 RR
D. Compliance
Bombardier Inc. recommends incorporation of Service Bulletin 84-24-53 at the
earliest opportunity unless otherwise directed by the operator’s airworthiness
authority.
NOTE: This service bulletin must be completed within 6,000 Flight Hours (FH)
from the release of this service bulletin.
A Transport Canada Airworthiness Directive is pending.
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).
F. Manpower
It will take an estimated 2 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 0.50
Close-Out 0.50
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 part(s) detailed in Paragraph(s) 2.A. and 2.B. may be obtained from any
Bombardier Aerospace Regional Aircraft authorized parts source. The price and
availability will be quoted at the time of order.

### Page 6

SERVICE BULLETIN 84-24-53
S.B. 84-24-53
Page 4 of 8
11 May 2012
Revision ‘A’ 16 May 2013 RR
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....................
L. References
Revision ‘A’ of this service bulletin was prepared to the engineering drawings and
related data that follows:
DRAWING SHEET REV
82420102 19 D
82420102 33 A
PCA 43701 Revision 2 (for internal reference only)
Transport Canada Airworthiness Directive Pending.
2. MATERIAL INFORMATION
A. Parts Required Per Aircraft
(1) Detailed Parts List:
Quantity
Per Aircraft
Part Number Description Remarks
1 MS21919WDG7 Clamp
1 M85052/2-6 Clamp
1 MS35207-263 Screw

### Page 7

SERVICE BULLETIN 84-24-53
S.B. 84-24-53
Page 5 of 8
11 May 2012
Revision ‘A’ 16 May 2013 RR
Quantity
Per Aircraft
RemarksDescriptionPart Number
1 AN960D10L Washer
1 MS21042L3 Nut
B. Parts Required to Modify Spares
None
C. Special Tools and Equipment Required
D. Existing Parts Accountability
None
3. ACCOMPLISHMENT INSTRUCTIONS
A. Job Set-Up
WARNING: MAKE SURE YOU 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: MAKE SURE YOU 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 24-00-00-861-802 and TASK
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) Gain access to the passenger compartment.

### Page 8

SERVICE BULLETIN 84-24-53
S.B. 84-24-53
Page 6 of 8
11 May 2012
Revision ‘A’ 16 May 2013 RR
(5) Remove the passenger compartment carpet, floor path emergency lights, seats,
and floor panels between X321.000 to X341.000 (refer to AMM TASK
25-25-06-000-801).
B. Procedure
PART A - INSPECTION (Configuration Check)
(1) In the underfloor (left side) area, locate frame at station X321.000 and station
X341.000 (refer to Figure 1).
(2) Do a visual inspection to confirm if the clamps between AC power feeder cables
and the hydraulic line are installed or not installed (refer to Figure 1 and Figure
2).
(3) If the clamps are installed, as shown in the Figure 2, do the Close Out section.
(4) If the clamps are not installed, do the PART B - RECTIFICATION.
PART B - RECTIFICATION (Damage Repair and Clamp Installation)
(1) Do a visual inspection of the AC power feeder cables and the hydraulic line for
damage due to chafing. Repair AC power feeder cables in accordance with
wiring standard practices (refer to WDM Chapter 20). Repair the hydraulic tube
(refer to AMM Task 20-20-00-220-801).
(2) Install the clamp MS21919WDG7 on the AC power feeder cables (refer to Figure
2).
(3) Install the clamp M85052/2-6 on the hydraulic line (emergency landing gear
down line).
(4) Attach both clamps together using screw MS35207-263, washer AN960D10L
and nut MS21042L3 (refer to Figure 2).
C. Close Out
(1) Install the passenger compartment carpet, floor path emergency lights, seats,
and floor panels between X321.000 to X341.000 (refer to AMM TASK
25-25-06-400-801).
(2) Remove all tools and equipment from the work area.
(3) On completion of this service bulletin, make the following entry in the
appropriate logbooks: “Service Bulletin 84-24-53 {i.e. Electrical Power - Wiring
Installation - Center Fuselage - Special Inspection and Rectification to Ensure
the Installation of Clamping Hardware between AC Power Feeder Cables and
Hydraulic Line} accomplished.”

### Page 9

SERVICE BULLETIN 84-24-53
S.B. 84-24-53
Page 7 of 8
11 May 2012
Revision ‘A’ 16 May 2013 RR
Inspection Area
Figure 1
FWD
AC POWER FEEDER CABLES
INSPECT THE AREA FOR CLAMP INSTALLATION
IF FOUND MISSING, INSTALL THE CLAMPS (REFER TO FIGURE 2).
BETWEEN AC POWER FEEDER CABLES AND THE HYDRAULIC TUBE.1
1

### Page 10

SERVICE BULLETIN 84-24-53
S.B. 84-24-53
Page 8 of 8
11 May 2012
Revision ‘A’ 16 May 2013 RR
Clamp Installation
Figure 2
INSTALL
MS21919WDG7
M85052/2-6
MS35207-263
CLAMP
CLAMP
SCREW
WASHER
AN960D10L
NUT
MS21042L3
AC POWER FEEDER CABLES
FWD
1

### Page 11

Jan 2009
SERVICE BULLETIN (SB) - - - RECORD OF INCORPORATION
- - - Q SERIES DASH 8 AIRCRAFT
To : CMDB Focal
Facsimile: (1) 416 375 4538
E- -mai l: cmdb.requests@aero.bombardier .com
From:
Company:
Phone: Extn:
Facsimile: Date:
E- -mai l:
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

### Page 12

Feb 2009
SERVICE BULLETIN (SB) - - - COMMENT SHEET - - - Q SERIES DASH 8 AIRCRAFT
To : SB Focal (T oronto), Bombardier Aerospace Commercial Aircraft
Phone: (1) 416 375 4078 Facsimile: (1) 416 375 4538
E- -mai l: syed.rizvi@aero.bombardier .com
From:
Company:
Phone: Extn:
Facsimile: Date:
E- -mai l:
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 T ooling V References V Publications Affected
2. MATERIAL INFORMATION
V Kit Content V Special T ools/Equipment V Parts to Modify Spares
V Consumables V Disposition of Existing Parts V Other
3. ACCOMPLISHMENT INSTRUCTIONS
V J o b S e t --- U p V Procedure V Close- - -Out V Te s t
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

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