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 Referencessection revised to convey the latest revision of the service bulletin and engineering documentation

- theACCOMPLISHMENT INSTRUCTIONS - Job Set-Upsection revised to change reference from PSM to AMM, for consistency

- theACCOMPLISHMENT INSTRUCTIONS - Proceduresection 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

# 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 Ensure 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

### 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 manufacturing 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 installed 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.

### 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.

### 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

### 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 Remarks Description Part 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.

### 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 powerfeeder 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.”

### 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

### 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

1Jan 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 VApproval V Manpower V Material VWeight 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