Revision ‘A’ 06 Aug 2012 DHC-8 (DASH 8) SERVICE BULLETIN 84-57-24 Wings - Center Section -Special Inspection - Heat Shield & D Nose - Relocation of Anchor Nut on Outboard Heat Shield to Avoid Harness Fouling on Leading Edge Rib - ModSum 4-110440 This page transmits Revision ‘A’ of Service Bulletin 84-57-24, pages 1 thru 14 dated 06 Aug 2012. This service bulletin is re-issued in its entirety for the reasons that follow: - the format of this service bulletin is updated to the latest standard. Revision bars are not applied to any format changes. Revision bars are applied only beside subject matter to identify technical changes or new information - added EMPHASIS statement before SUBJECT - the Compliance section is revised with new statement. Added AD number - the Referencessection is revised to convey the latest revision of the service bulletin and engineering documentation - revised part of step 3.B.(1) theACCOMPLISHMENT INSTRUCTIONS section from ‘visually inspect’ to ‘do a detailed inspection of’ - revised part of step 3.B.(8) theACCOMPLISHMENT INSTRUCTIONS section from ‘and Figure 3 or Figure 4’ to ‘and Figure 4 or Figure 5’. The Compliance in the previous issues of this service bulletin is not affected by this revision. No additional rework to the aircraft is introduced by this revision. Remove Service Bulletin 84-57-24 Initial Issue and replace with attached. Previous issues of Service Bulletin 84-57-24: Initial issue - Pages 1 thru 14 dated 30 Sep 2011Revision ‘A’ 06 Aug 2012

# D

S.B. 84-57-24 Page 1 of 14 30 Sep 2011 MG Revision ‘A’ 06 Aug 2012 

# SERVICE BULLETIN Customer Support ATA SYSTEM: 5700 NUMBER: 84-57-24 

### BOMBARDIER AEROSPACE REGIONAL AIRCRAFT CONSIDER THIS SERVICE BULLETIN TO BE PARTICULARLY SIGNIFICANT AND URGES OPERATORS TO PROMPTLY EVALUATE THE CONTENTS

SUBJECT Wings - Center Section -Special Inspection - Heat Shield & D Nose - Relocation of Anchor Nut on Outboard Heat Shield to Avoid Harness Fouling on Leading Edge Rib - ModSum 4-110440
1. PLANNING INFORMATION A. Effectivity Aircraft Affected: In-Service: DHC-8 Aircraft Models 401 and 402 Serial Numbers 4001, 4003 thru 4382. Verification: ModSum 4-110440 has been incorporated on DHC-8 Aircraft Model 402 Serial Number 4249 per Post Verification Service Bulletin 84-57-24. 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: Operator’s have reported wire chafing damage at the inboard end rib of the landing light assembly on both left hand and right hand sides.

### SERVICE BULLETIN 84-57-24

S.B. 84-57-24 Page 2 of 14 30 Sep 2011 MG Revision ‘A’ 06 Aug 2012 Cause: A potential fouling condition exists between a wire harness and the inboard end rib of the landing light assembly on both the left hand and right hand sides. This harness includes wires for the flare and approach lights, the position lights and the dual distributing valves. Solution: Do an inspection of the affected wire harness and repair the harness if chafing exists. In addition, relocate and install a new anchor nut to eliminate the fouling condition between the wiring harness and the leading edge rib. NOTE: Relocation and installation of new anchor nut to be completed on both the left and right hand sides, even if there are no signs of 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 thru each main gear and main gear door mechanism - the left and right hand nacelle forward fairing assemblies and landing light leading edge assemblies are removed - the wiring harness on the left or right hand side is visually inspected for chafing. The harness is repaired if damage is found - abrasion protection is installed to the harness - if installed, the existing plastic grommet is removed and discarded - the anchor nut is removed and replaced with a new one relocated down by one fastener pitch on the leading edge rib - the wiring harness is installed to the anchor nut with the existing clamps, washer and a new screw and spacer - a new grommet is installed to the hole - the rework is done on the opposite side - the nacelle forward fairing assemblies and the landing light leading edge assemblies are installed

### SERVICE BULLETIN 84-57-24

S.B. 84-57-24 Page 3 of 14 30 Sep 2011 MG Revision ‘A’ 06 Aug 2012 - an operational test of the landing lights is done - close out. D. Compliance Bombardier Inc. highly recommend that ModSum 4-110440 be incorporated at the earliest opportunity unless otherwise directed by the operator’s airworthiness authority. Transport Canada Airworthiness Directive CF-2012-05. 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 8.50 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 3.00 Inspection/Procedure 2.00 Test / RTS 0.50 Close-Out 3.00 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 part(s) and material(s) detailed in Paragraph(s) 2.A. and 2.B. may be either furnished or fabricated from the operator’s existing stock, purchased as single items from Bombardier Aerospace Regional Aircraft or purchased directly from industry sources. H. Tooling - Price and Availability None

### SERVICE BULLETIN 84-57-24

S.B. 84-57-24 Page 4 of 14 30 Sep 2011 MG Revision ‘A’ 06 Aug 2012 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

.................................. L. References Revision ‘A’ of this service bulletin was prepared to the engineering drawings and related data that follows: DRAWING SHEET REV

8DK4179 1 A

8Z9340 1 A ModSum 4Q110440 Rev. ‘B’ ModSum 4-110440 Rev. ‘B’ PCA 43644 Revision 3 (for internal reference only) Transport Canada Airworthiness Directive CF-2012-05. 2. MATERIAL INFORMATION A. Parts Required Per Aircraft (1) Detailed Parts List:
Quantity Per Aircraft Part Number Description Remarks
2 NAS1801-3-24 Screw (full thread) 2 NAS43DD3-64FC Spacer

### SERVICE BULLETIN 84-57-24

S.B. 84-57-24 Page 5 of 14 30 Sep 2011 MG Revision ‘A’ 06 Aug 2012 Quantity Per Aircraft Remarks Description Part Number
6 B0205016AD4-4S Rivet see NOTE: 1 2 B0204033-3-4 Anchor Nut see NOTE: 2 2 MS21266-1N Grommet
NOTE 1: B0205016AD4-4S is equivalent to MS20470AD4-4S.
NOTE 2: B0204033-3-4 is equivalent to T8059S1032B-1CPC (Textron Cherry) or 52LHA71-4-02 (SPS Technologies) or T8059S1032B-1CPC (Republic Fasteners). (2) In addition to the above parts, the following materials are required for the completion of this service bulletin and may be procured as single items from Bombardier Aerospace Regional Aircraft or purchased directly from industry sources. Addresses of manufacturers and suppliers not shown below are listed in either Maintenance Manual Chapter 20 or in Structural Repair Manual Chapter 51 or, for 400 Series Aircraft, in Consumable Products Manual PSM 1-84-18.

Part Number Qty. Per Aircraft Description DHMS C4.01 as required Epoxy Primer, Type 2 F19 MIL-C-5541 as required Chemical Conversion Coating, C1 DHMS A6.09 Epoxy Adhesive 9 oz or

- Adhesive, Fastweld #10 B. Parts Required to Modify Spares None C. Special Tools and Equipment Required None

### SERVICE BULLETIN 84-57-24

S.B. 84-57-24 Page 6 of 14 30 Sep 2011 MG Revision ‘A’ 06 Aug 2012 D. Existing Parts Accountability None 3. ACCOMPLISHMENT INSTRUCTIONS A. Job Set-Up (1) Placard and select all aircraft electrical power to OFF. Refer to AMM TASK 24-00-00-861-802, TASK 24-00-00-910-801 and obey all relevant WARNINGS and CAUTIONS. (2) Make sure that lock pins are installed thru each main gear and main gear door mechanism. (3) Make sure the nose gear ground lock is engaged. (4) Refer to Figure 1 and set up work platforms or ladders as required to gain access to the wing leading edges at the nacelles. Make sure the work platforms or ladders are electrically grounded. (5) Refer to Figure 2 and the applicable steps in AMM TASK 57-23-01-000-801 and remove and keep left and right hand side landing light leading edge assemblies 85720301 (512AL-left hand side and 612AR-right hand side). (6) Refer to Figure 3 and AMM TASK 54-12-01-000-801 and remove and keep nacelle forward fairing assemblies 87144008 (412CT-left hand side and 422CT-right hand side). B. Procedure (1) Refer to Figure 6 and do a detailed inspection of the wire harness at left or right hand anchor nut location for chafing damage. If damaged, repair the wiring harness per Wiring Diagram Manual Chapter 20-16-10 and Chapter 20-16-20. (2) Add abrasion protection to the harness if required in accordance with Wiring Diagram Manual 20-12-10-201-Wiring Maintenance Practices-Section 10, Installation of Edging Grommet and Spiral Wrap. (3) If installed, remove and discard existing plastic grommet. (4) Refer to Figure 4 (left hand side) or Figure 5 (right hand side) and remove and keep existing clamps DSC184-9 and MS21919WDG6. Discard spacer and screw, keep washer. (5) Remove and discard existing anchor nut. (6) Refer to SRM TASK 51-42-05-00-01, Figure 4 or Figure 5 and plug top rivet hole using one rivet B0205016AD4-4S.

### SERVICE BULLETIN 84-57-24

S.B. 84-57-24 Page 7 of 14 30 Sep 2011 MG Revision ‘A’ 06 Aug 2012 (7) Refer to SRM TASK 51-42-05-00-01, Figure 4 or Figure 5 and install new anchor nut B0204033-3-4 at location shown using two rivets B0205016AD4-4S. (8) Refer to SRM TASK 51-22-45-02-01 or TASK 51-22-35-02-01, AMM TASK 20-00-33-400-801 and Figure 4 or Figure 5 and install new grommet MS21266-1N as shown with DHMS A6.09 epoxy adhesive or Fastweld #10 adhesive. (9) Install wiring harness with removed clamps DSC184-9 and MS21919WDG6 to new anchor nut using kept washer NAS1149D0316H, new spacer NAS43DD3-64FC and new screw NAS1801-3-24. Torque screw to 20 - 25 inch pounds. (10) Re-finish any scuffed surface on the leading edge rib with C1 alodine & F19 epoxy primer. (11) Temporarily install landing light leading edge assembly 85720301 with four screws. Do a visual inspection of the relocated harness support area for any fouling condition. (12) Remove landing light leading edge assembly 85720301. (13) Repeat steps B.(1) thru B.(12) for the opposite side. C. Close Out (1) Refer to AMM TASK 54-12-01-400-801 and install nacelle forward fairing assemblies 87144008 (412CT-left hand side and 422CT-right hand side). (2) Refer to applicable steps in AMM TASK 57-23-01-400-801 and install landing light leading edge assemblies 85720301 (512AL-left hand side and 612AR-right hand side). (3) Refer to the steps in section 5. A., B., C., D. of AMM TASK 33-41-01-400-801 and do an operational test of the landing lights. (4) Remove all tools and equipment from the work area. (5) 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.

### SERVICE BULLETIN 84-57-24

S.B. 84-57-24 Page 8 of 14 30 Sep 2011 MG Revision ‘A’ 06 Aug 2012 Location of Rework Figure 1

### SERVICE BULLETIN 84-57-24

S.B. 84-57-24 Page 9 of 14 30 Sep 2011 MG Revision ‘A’ 06 Aug 2012 Removal / Installation of Landing Light Leading Edge Figure 2 LEGEND 1. BOLT 2. SILICONE SEAL 3. LEADING EDGE 1 2
3

1 512AL-LEFT HAND SIDE 612AR-RIGHT HAND SIDE

### SERVICE BULLETIN 84-57-24

S.B. 84-57-24 Page 10 of 14 30 Sep 2011 MG Revision ‘A’ 06 Aug 2012 Removal / Installation of Leading Edge Fairing - Forward Nacelle Figure 3 412CT-LEFT HAND SIDE 422CT-RIGHT HAND SIDE

### SERVICE BULLETIN 84-57-24

S.B. 84-57-24 Page 11 of 14 30 Sep 2011 MG Revision ‘A’ 06 Aug 2012 Looking Inboard on Leading Edge Rib - LH Side Figure 4 SCREW NAS1801-3-24 SPACER NAS43DD3-64FC RIVET B0205016AD4-4S

PLASTIC GROMMET MS21266-1N ADHESIVE FASTWELD #10 OR EPOXY DHMS A6.09 ANCHOR NUT B0204033-3-4 RIVET B0205016AD4-4S

CLAMP (DSC184-9 OR DSC184-10) MAKE SURE CLAMP DOES NOT CONTACT PLASTIC GROMMET CLAMP (MS21919WDG6) RIVET EDGE DISTANCE FROM CUT OUT EDGE MIN.

### SERVICE BULLETIN 84-57-24

S.B. 84-57-24 Page 12 of 14 30 Sep 2011 MG Revision ‘A’ 06 Aug 2012 Looking Inboard on Leading Edge Rib - RH Side Figure 5 SCREW NAS1801-3-24 SPACER NAS43DD3-64FC RIVET B0205016AD4-4S

ANCHOR NUT B0204033-3-4 RIVET B0205016AD4-4S

PLASTIC GROMMET MS21266-1N ADHESIVE FASTWELD #10 OR EPOXY DHMS A6.09 CLAMP (MS21919WDG6)

RIVET EDGE DISTANCE FROM CUT OUT EDGE MIN.

CLAMP (DSC184-9 OR DSC184-10) MAKE SURE CLAMP DOES NOT CONTACT PLASTIC GROMMET

### SERVICE BULLETIN 84-57-24

S.B. 84-57-24 Page 13 of 14 30 Sep 2011 MG Revision ‘A’ 06 Aug 2012 Fouling Condition On Leading Edge Rib - Pre Mod Illustration Figure 6 INBOARD

### SERVICE BULLETIN 84-57-24

S.B. 84-57-24 Page 14 of 14 30 Sep 2011 MG Revision ‘A’ 06 Aug 2012 

### This Page Intentionally Blank 2Jan 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