# De Havilland Canada Service Bulletin 84-55-10

Copy: Revision A ("84-55-10A"), 26 pages: PDF https://openairdocs.org/files/sha256/a4/bb/a4bb7eaf32f6424302d3cfd3c0fb1498d21302f98d3f5bdde3dd5c5b854b462a; text https://openairdocs.org/service-documents/bombardier/sb-84-55-10/file/a4bb7eaf32f6.md. Rights: © Bombardier Inc. Filed by the FAA in regulations.gov docket FAA-2020-0101; AD 2020-09-12 incorporates this document by reference. Not covered by OpenAirDocs’ CC0 dedication.

## Details

- Manufacturer: [Bombardier](https://openairdocs.org/service-documents/bombardier.md) (issued as De Havilland Canada)
- Type: Service bulletin (Service Bulletin)
- Number: 84-55-10
- Latest revision known: 84-55-10, Revision A, dated July 25, 2019 (OpenAirDocs)
- Page: https://openairdocs.org/service-documents/bombardier/sb-84-55-10

## ADs that cite it (1) (OpenAirDocs)

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

- [AD 2020-09-12](https://openairdocs.org/ad/2020-09-12.md), effective Jun 24, 2020: Revision A

Also cited in [1 proposed AD](https://openairdocs.org/service-documents/bombardier/sb-84-55-10/proposed.md).

## Text (26 pages)

Rights: © Bombardier Inc. Filed by the FAA in regulations.gov docket FAA-2020-0101; AD 2020-09-12 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.

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D H C --- 8 ( D A S H 8 )
S E R V I C E B U L L E T I N 8 4 --- 5 5 --- 1 0
Stabilizers - - - Elevator - - - Elevator Power Control Unit (PCU) Arm Fittings - - -
Inspection and Rectification - - - ModSum 4- - - 113992
This page transmits Revision ‘A’ of Service Bulletin 84- - -55- - -10, pages 1 thru 22,
dated 25 Jul 2019
This service bulletin is re- - -issued in its entirety for the reasons that follow:
--- T h eReferences section is revised to convey the latest revision of the service
bulletin
--- T h eParts Required Per Aircraft section is revised to show the correct email
address for ordering drawings
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 previous issue of Service Bulletin 84- - -55- - -10 and replace with
attached.
Previous issue(s) of Service Bulletin 84- - -55- - -10:
Initial issue - - - Pages 1 thru 22 dated 29 May 2019

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SERVICE BULLETIN
Customer
Support
ATA SYSTEM: 5521 NUMBER: 84- - -55- - -10
DE HAVILLAND AIRCRAFT OF CANADA LIMITED (DHC) CONSIDERS
URGES OPERATORS TO PROMPTL Y EVALUATE THE CONTENTS
THIS SERVICE BULLETIN TO BE PARTICULARL Y SIGNIFICANT AND
SUBJECT : Stabilizers - - - Elevator - - - Elevator Power Control Unit (PCU) Arm
Fittings - - - Inspection and Rectification - - - ModSum 4- - - 113992
1. PLANNING INFORMA TION
NOTE: It is recommended that this service bulletin to be done at the same
t i m e a s s e r v i c e b u l l e t i n 8 4 --- 5 5 --- 0 9 .
A. Effectivity
Aircraft Affected:
In- - -Service: DHC- - -8 Aircraft Models 401 and 402 Serial Numbers 4001,
4003 thru 4620.
NOTE: Only elevator assemblies P/N 85527021- - -005/- - -006 with serial
numbers MMC4255 thru MMC4276 are affected by this service bulletin.

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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 DHC 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
85527021- - -005/- - -006 with S/N
MMC4255 thru MMC4276
Elevator Assembly
B. Reason
Problem: Some elevator Power Control Unit (PCU) arm fittings were manufactured
with missing or undersize fillet radii. This reduces the fatigue life of the arm
fittings.
Cause: This was a workmanship error during detail fabrication.
Solution: This service bulletin provides the instructions to do the inspection of the
PCU arm fittings. If the fittings have missing or undersize radii, the affected
fitting is removed and replaced.
C. Description
The procedures in this service bulletin give the instructions to do the tasks that follow:
- - - maintenance records are checked for the affected elevator serial numbers
- - - 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
- - - work scissor lift(s) or platforms are set as required to gain access to horizontal
stabilizer.

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- - - access panels are opened
Part - - - A (Inspection)
- - - an inspection of the fillet radii on the elevator PCU arm fittings is done
- - - if the radii are within specification access panels are closed
Part - - - B (Rectification)
- - - if the radii are not within specification the elevator is removed to gain access to the
affected PCU arm fitting
- - - the PCU arm fitting is removed and replaced with a new one
- - - elevators are installed
- - - close out.
D. Compliance
DE HAVILLAND AIRCRAFT OF CANADA LIMITED highly recommend incorporation of
ModSum 4- - -113992 at the earliest opportunity unless otherwise directed by the
operator’s airworthiness authority.
A Transport Canada Airworthiness Directive 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
# 1 9 --- Q --- 0 1 .
This service bulletin does not affect Airworthiness Limitations (AWLs) or Damage
T olerance Inspections (DTIs).
F. M a n p o w e r
P a r t A --- I n s p e c t i o n
It will take an estimated 5 man- - -hours to complete Part A - - - Inspection given in the
ACCOMPLISHMENT INSTRUCTIONS in this service bulletin. The breakdown of
man - - - hours is shown in the table that follows:

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TASK M A N --- H O U R S
J o b S e t --- U p 2.00
Procedure in Part A 1.00
T e s t/R T S 0.00
Close- - -Out 2.00
Part B - - - Rectification
It will take an estimated 14 man- - -hours to complete PART B - - - Rectificationgiven in
the ACCOMPLISHMENT INSTRUCTIONS in this service bulletin. The breakdown of
man - - - hours is shown in the table that follows:
TASK M A N --- H O U R S
J o b S e t --- U p 2.00
Procedure in Part B 8.00
T e s t/R T S 2.00
Close- - -Out 2.00
G. Material - - - Price and Availability
The ModKit(s) required to do this service bulletin is/are listed in the table below:
Kit Number Description
8MK4819- - -001 K i t --- E l e v a t o r, P C U A r m F i t t i n g
Inspection and Rectification
NOTE: Whole 8MK4819- - -001 kit is not procurable. It is intended that operators
order fittings and shims as required after they find fittings with
insufficient radii.
NOTE: Please note that the full Modkit kit required to do this service bulletin is
listed in the above table for reference only. Refer to section 2.A. and
order part quantities sufficient to rep lace fittings which have insufficient
fillet radii.

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Operators should submit a purchase orde r through the Customer Response Center
(CRC) to the Customer Accounts Service T eam (CAST) at DHC specifying aircraft
serial number(s) to:
DE HAVILLAND AIRCRAFT OF CANADA LIMITED
Material Services
123 Garratt Blvd.
To r o n t o
Ontario
Canada M3K- - -1Y5
DHC Phone Numbers :
North America:T oll Free: 1 (844)- - -CRC- - -CRC0 (1 (844) 272- - -2720) or
Direct: 1 (514) 855- - -8500
DHC Emails:
Parts: Europe, Middle East, Africa, and Russia: emear.parts@dehavilland.com
Americas and Rest of World: parts@dehavilland.com
H. T ooling - - - Price and Availability
None
I. Weight and Balance
A/C T ype and
Model
Weight (Lb) Arm (Inches)
Moment
(Inches x Lb)
x 0.001
D H C --- 8 M o d e l 4 0 1 Negligible --- ---
D H C --- 8 M o d e l 4 0 2 Negligible --- ---

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J. Electrical Load Data
Not affected
K. Publications Affected
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
8MK4819 1 ---
8Z7317 1 D
8Z7317 2 ---
8Z7317 3 A
8Z7317 4 B
ModSum 4- - -113992 Rev. ‘H’
ModSum 4Q113992 Rev. ‘H’
PCA 46956 Revision 0 (for internal reference only)
Transport Canada Airworthiness Directive Pending.
2. MATERIAL INFORMA TION
A. Parts Required Per Aircraft
(1) Modification Kit 8MK4819- - -001

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(2) Detailed Kit Content:
Quantity Per Kit
--- 0 0 1
Part Number Description Remarks
Ref 8MK4819 Kit Drawing Drawing only
Ref 8Z7317 Retrofit Drawing only
12 B0206017TP8 Collar Hi- - -Lite
12 B0206016CY8 Collar Hi- - -Lite
24 B0206016CY6 Collar Hi- - -Lite
36 B0206016CY5 Collar Hi- - -Lite
15 NAS9305E- - -4- - -04 Rivet
115 NAS9305E- - -4- - -03 Rivet
25 NAS9305E- - -4- - -02 Rivet
25 NAS9304E- - -4- - -03 Rivet
130 NAS9304E- - -4- - -02 Rivet
40 NAS9303E- - -5- - -05 Rivet
50 NAS9303E- - -5- - -04 Rivet
130 NAS9303E- - -5- - -03 Rivet
80 NAS9303E- - -5- - -02 Rivet
12 B0206003AG- - -8- - -9 P i n H i --- L i t e
12 B0206002AG- - -8- - -8 P i n H i --- L i t e
24 B0206002AG- - -6- - -8 P i n H i --- L i t e
12 B0206001AG- - -5- - -8 P i n H i --- L i t e
24 B0206001AG- - -5- - -7 P i n H i --- L i t e
130 B0205016AD3- - -4S Rivet
6 CSP469B- - -330- - -270 Shim Laminated
6 CSP469B- - -323- - -300 Shim Laminated
3 85527270- - -004 Arm Fitting Assy
3 85527270- - -003 Arm Fitting Assy
Listed drawings that are required to complete the kits above can be requested by
writing to the following e- - -mail address:
dwg.request@dehavilland.com

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(3) In addition to the above part(s), the following material(s) are required for the
completion of this service bulletin and may be procured as single items from
DHC or purchased directly from industry sources.
Each consumable product listed in the table below is given its own unique
Product ID Number. The number is used to identify a particular recommended
product, the specifications and the trade names any of which can be used
unless specified otherwise (refer to PSM 1- - -84- - -18 Consumable Products
Manual).
Consumable
Product ID
Number
Qty. Per Aircraft Description Remarks
06- - -01 A/R Sealant, Fillet DHMS S3.01/B2
06- - -02 A/R Sealant, Corrosion
Inhibiting
D H M S S 3 . 0 6 C --- 8 0
(See NOTE)
07- - -02A A/R F19 Chromate
Epoxy Primer
MIL- - -P- - -23377
07- - -08 A/R F24 Enamel,
Polyurethane
DHMS C4.04
07- - -21 A/R Alodine MIL- - -C- - -5541
NOTE: Alternate sealant 06- - -02 Proseal P/S 870 C- - -12 Sealant to
MIL- - -PRF- - -81733.
B. Parts Required to Modify Spares
None

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C. Special T ools and Equipment Required
Reference Designation Remarks
GSB2730004 Alignment T ool Left Hand
GSB2730005 Alignment T ool Right Hand
Item #MTT186- - -101
Mfr. Model #186- - -101
UNSPSC # 41111617
Radius Gauge Manufacturer: Mitutoyo
Range 0.031 - - - 0.250 in.
See Note below
NOTE: Any gauge with the capability to measure radii of 0.090” or less are
acceptable alternatives. If radius is bigger than 0.090”, the radius
meets drawing intent and need not be measured.
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
85527021- - -005 Elevator As-
sembly (L/H)
1 C RWK 8Z7317- - -001 R
85527021- - -006 Elevator As-
sembly (R/H)
1 C RWK 8Z7317- - -002 R
IC Interchangeability Code
A Not interchangeable.
B Removed Part. No direct replacement.
C Conditionally Interchangeable. Inst allation 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 DHC 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
If it is not possible to complete all the instructions of this service bulletin because of the
configuration of the aircraft, speak with a representative of DHC in the CRC at 1 (844)
272- - -2720 (1 (844) CRC- - -CRC0) or email at thd.qseries@dehavilland.com for analysis and
to get an approved disposition to complete this service bulletin.
A . J o b S e t --- U p
NOTE: Before starting work, inspect all maintenance records or elevator
dataplates to determine the elevator serial numbers. If the elevator
serial numbers are outside the affected range (MMC4255 thru
MMC4276), no further action is required. Go to 3.C. Close Out
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 ACCIDENTALL Y
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 ACCIDENTALL Y CLOSE THE LANDING GEAR DOORS. THIS
CAN CAUSE INJURIES TO PERSONS AND DAMAGE TO THE
EQUIPMENT .

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WARNING: MAKE SURE YOU INSTALL THE LOCKPINS ON THE LANDING
GEAR DOORS. MAKE SURE YOU DISCONNECT THE LANDING
GEAR DOORS. IF YOU DO NOT DO THIS THE LANDING GEAR
DOORS WILL CLOSE WHEN YOU APPL Y THE HYDRAULIC
PRESSURE. THIS CAN CAUSE INJURIES TO PERSONS AND
DAMAGE TO THE EQUIPMENT .
(1) Placard and select all aircraft electrical power to OFF . Obey all relevant
W A R N I N G S a n d C A U T I O N S ( r e f e r t o A M M T A S K ’ S 2 4 --- 0 0 --- 0 0 --- 8 6 1 --- 8 0 2 a n d
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 wheel chocks in front and behind the landing gear tires.
(5) Set up work platforms as required to gain access to the horizontal stabilizer.
Make sure the work platforms are electrically grounded.
(6) Remove pressure from the No. 1 and No. 2 hydraulic system (refer to AMM TASK
29- - -00- - -00- - -863- - -802).
(7) Remove pressure from the No. 3 hydraulic system (refer to AMM TASK
29- - -00- - -00- - -863- - -804).
B. Procedure
Part A - - - Inspection of the Elevator PCU Arm Fittings
(1) Remove access covers P/N 85527223, 85527203, 85527222 and retain hardware.
(2) Do a detailed inspection of PCU arm fittings (P/N 85527270) (three per side) as
follows: (refer to drawing 8Z7317, Sht. 2, VIEW ON ARROW A and VIEW ON
ARROW B)

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(a) Examine the fitting assemblies for fillet radii. The use of a radius gauge is
required. Make sure that paint does not obscure the radius.(refer to drawing.
8Z7317, Sht. 2 DETAIL D)
(b) If undersize fillet radii are discovered, conduct a detailed visual inspection for
cracking.
(3) If you find that fillet radii are undersized, go to Part B - - - Rectification.
(4) If you find cracks in the fillet radii, go to Part B Rectification before next flight.
(5) If the fillet radii are correct and the parts are not cracked re- - -identfy to
“8Z7317- - -501” on the left hand elevator front spar face and “8Z7317- - -502” on
the right hand elevator front spar face. Part mark with an indelible marker (refer to
AMM 20- - -00- - -01- - -910- - -801) Reinstall access covers P/N 85527223, 85527203,
85527222 with retained hardware and go to C. Close Out .
Part B - - - Rectification
NOTE 1: Remove and replace only the arm fittings with undersize fillet radii
and/or cracking.
NOTE 2: When doing structural rework make sure to deburr affected rivet holes
then apply a layer of alodine and touch up with epoxy chromate primer
as required.
NOTE 3: It is recommended that a fixture be manufactured that will hold the
elevator in a vertical position to allow work from both sides. Moving the
elevator after the lower skin has been removed and before the
alignment tool has been installed could lead to misalignment of the
PCU fittings.
(1) Remove elevator(s) and retain hardware. (refer to to AMM TASK
27- - -34- - -01- - -000- - -801)
(2) Locate, remove and retain lower mid skin panel (P/N 85527112) using the
instructions that follow: (refer to drawing 8Z7317, Sht. 3)
(a) Carefully remove rivets marked as thus .
(b) Remove and retain skin splices P/N 85527114 (2 off).

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(3) Locate and install alignment tool GSB2730004 (LH) and/or GSB2730005 (RH) per
AMM T ask 55- - -20- - -11- - -960- - -801. (refer to Figures 1, 2 and 3)
(4) Carefully remove hi- - -lite fasteners on the affected PCU fitting(s). Refer to AMM
T ask 55- - -20- - -11- - -960- - -801.
(a) Remove and discard PCU fitting.
(b) Remove and retain shims to use as a guide for profiling new shims. Do not
reinstall original shims.
(5) Install new PCU fitting onto alignment tool and measure gaps. Refer to AMM T ask
55- - -20- - -11- - -960- - -801.
(a) Fit shims CSP469B- - -330- - -270 (f/n 11) and CSP469B- - -323- - -300 (f/n 10)
between upper skin panel and spar. (refer to drawing 8Z7317, sht. 4, SECTION
H- - -H and flagnote 11 )
(6) Disassemble, clean, deburr and treat exposed surfaces with alodine, 1200S
and/or 1200 and then apply epoxy polyamide primer on all applicable rework
a r e a s . R e f e r t o a p p l i c a b l e i n s t r u c t i o n i n S R M T A S K 5 1 --- 2 1 --- 1 0 --- 0 2 --- 0 1 a n d T A S K
5 1 --- 2 5 --- 1 0 --- 0 2 --- 0 1.
(7) All retrofit rework of each elevator and related parts shall be accomplished in
accordance with the NOTES that follow:
NOTE 1: Before installation of any fastener verify that hole size meets
interference fit. Oversize fasteners maybe used if required. If there are
any issues with edge distance or fastener pitch contact the T echnical
Help Desk in T oronto at telephone (416) 375- - -4000 or facsimile (416)
375- - -4539 or e- - -mail: thd.qseries@dehavilland.com.
NOTE 2: Use of oversize pins are permitted if the existing fastener holes are
outside the following limits:
5/32 inch = dia. 0.1590/0.1620 inch
3/16 inch = dia. 0.1850/0.1880 inch
1/4 inch = dia. 0.2450/0.2480 inch
NOTE 3: Unless directed otherwise use gripping pins to hold together any of the
parts given in the steps that follow. Final assembly of parts using
required fasteners will be given later after it is determined that all new

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and retained parts are attached in correct locations and aligned as
required.
NOTE 4: Install shims to agree with applicable instructions in Aircraft
Maintenance Manual PSM 1- - -84- - -2 (AMM) Chapter 20- - -10- - -28).
NOTE 5: Fay seal mating surface with corrosion inhibiting sealant 06- - -02 to
agree with applicable instructions in AMM TASK
51- - -23- - -00- - -390- - -801.
Re- - -apply fay seal to any existing mating surfaces where fay seal is
visible on original parts.
NOTE 6: T ouch- - -up all unpainted surfaces and new fasteners with
fluid- - -resistant chromate epoxy primer (F19) to agree with applicable
instructions in SRM Chapter 51- - -25- - -10.
NOTE 7: T ouch- - -up all exposed chromate epoxy primer (F19) painted surfaces
(included fasteners) with polyurethane enamel (F24) white or customer
supplied paint to agree with applicable instructions in SRM Chapter
51- - -25- - -05.
NOTE 8: Replace one PCU fitting at a time. All upper skin and web hi- - -lites are
to be installed before removing the next jig pin and the next PCU
fitting.
(8) Using gripping pins locate PCU fitting to the elevator spar and install shims.
(9) Install shims and PCU fitting(s). (refer to drawing 8Z7317, sht 2, sht 4, and
flagnotes 8 , 12 and 13 )
(a) Remove alignment tool GSB2730004 (LH) and/or GSB2730005 (RH).
(10) Locate and install lower skin panel P/N 85527112. (refer to drawing 8Z7317, sht
3, VIEW ON ARROW F and flagnotes 8 and 9 )
(11) Locate and install skin splices P/N 85527114 using B0205016AD3- - -4S rivets.
(refer to drawing 8Z7317, sht 3, VIEW ON ARROW F)
(12) Fillet seal around periphery of PCU arm f itting using 06- - -01 sealant. (refer to
drawing 8Z7317,sht 2 VIEW ON ARROW A, VIEW ON ARROW B, SECTION C- - -C

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and flagnote 14 )
(13) Re- - -identify reworked elevator(s) as follows: (refer to drawing 8Z7317, sht 1,
flagnote 16 , sht 4, SECTION G- - -G and AMM TASK 20- - -00- - -01)
(a) For L/H elevator re- - -identify as P/N 8Z7317- - -001.
(b) For R/H elevator re- - -identify as P/N 8Z7317- - -002.
(14) Reinstall access covers P/N 85527223, 85527203 and 85527222 using retained
hardware.
(15) Re- - -install elevator using retained hardware. (refer to AMM TASK
27- - -34- - -01- - -400- - -801)
C. Close Out
(1) Remove all tools and equipment from the work area.
(2) On incorporation of this ModSum 4- - -113992, make an entry that conforms to
local regulatory requirements in the applicable logbook(s). If only Part A of this
service bulletin is completed and fillet radii were found undersized (deferred Part
B) , u s e o n l y S e r v i c e B u l l e t i n 8 4 --- 5 5 --- 1 0 { S t a b i l i z e r s --- E l e v a t o r s --- R e t r o f i t ---
Elevator Front Spar - - - Elevator Power Control Unit (PCU) Arm Fittings - - -
Inspection and Rectification } Part A as reference and detail exact limit of work
completed.
(3) Enter ModSum 4- - -113992, only after complete and functional incorporation of all
w o r k d e f i n e d i n t h i s S e r v i c e B u l l e t i n 8 4 --- 5 5 --- 1 0 { S t a b i l i z e r s --- E l e v a t o r s ---
Retrofit - - - Elevator Front Spar - - - Elevator Power Control Unit (PCU) Arm Fittings
- - - Inspection and Rectification } perPart B is embodied.
(4) If fittings with undersized fillet radii and/or cracks are found, report back to DHC
T echnical Help Desk with Elevator S/N and quantity of discrepant fittings found
on each elevator.

### Page 18

S E R V I C E B U L L E T I N 8 4 --- 5 5 --- 1 0
S . B . 8 4 --- 5 5 --- 1 0
Page 16 of 22
29 May 2019
JR
Revision ‘A’ 25 Jul 2019
Alignment T ool
Figure 1 , Sheet 1
NOTE: L/H SHOWN R/H OPPOSITE

### Page 19

S E R V I C E B U L L E T I N 8 4 --- 5 5 --- 1 0
S . B . 8 4 --- 5 5 --- 1 0
Page 17 of 22
29 May 2019
JR
Revision ‘A’ 25 Jul 2019
Mid Hinge Location
Figure 1 , Sheet 2
STAINLESS HAND
KNOB
CLAMPING PIN
CLAMPING COLLAR
JIG PIN

### Page 20

S E R V I C E B U L L E T I N 8 4 --- 5 5 --- 1 0
S . B . 8 4 --- 5 5 --- 1 0
Page 18 of 22
29 May 2019
JR
Revision ‘A’ 25 Jul 2019
Outer Hinge Location
Figure 1 , Sheet 3

### Page 21

S E R V I C E B U L L E T I N 8 4 --- 5 5 --- 1 0
S . B . 8 4 --- 5 5 --- 1 0
Page 19 of 22
29 May 2019
JR
Revision ‘A’ 25 Jul 2019
View on Hinge
Figure 1 , Sheet 4
POWER CLECO

### Page 22

S E R V I C E B U L L E T I N 8 4 --- 5 5 --- 1 0
S . B . 8 4 --- 5 5 --- 1 0
Page 20 of 22
29 May 2019
JR
Revision ‘A’ 25 Jul 2019
PCU Location Clamping
Figure 2 , Sheet 1

### Page 23

S E R V I C E B U L L E T I N 8 4 --- 5 5 --- 1 0
S . B . 8 4 --- 5 5 --- 1 0
Page 21 of 22
29 May 2019
JR
Revision ‘A’ 25 Jul 2019
PCU Fitting T ool
Figure 2, Sheet 2
PCU BRACKET
LOCATOR
ASS’Y
LOCK
COLLAR
ADJUSTMENT
KNOB

### Page 24

S E R V I C E B U L L E T I N 8 4 --- 5 5 --- 1 0
S . B . 8 4 --- 5 5 --- 1 0
Page 22 of 22
29 May 2019
JR
Revision ‘A’ 25 Jul 2019
Alignment T ool with Angle Assembly
Figure 3
POWER CLECO
POWER
CLECO
ADJUSTMENT KNOB
ADJUSTMENT KNOB
CAP SCREW
1

### Page 25

Jul 2019
SERVICE BULLETIN (SB) - - - RECORD OF INCORPORATION
- - - Q SERIES DASH 8 AIRCRAFT
To : CMDB Focal
Email: cmdb.request@dehavilland.com
From:
Company:
Phone: Extn:
Facsimile: Date:
Email:
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:
Email PDF to:
cmdb.request@dehavilland.com

### Page 26

Jun 2019
SERVICE BULLETIN (SB) - - - COMMENT SHEET - - - Q SERIES DASH 8 AIRCRAFT
To : SB Focal, DE HAVILLAND AIRCRAFT OF CANADA LIMITED
Phone: 1 (416) 373 - - -5098
Email: george.moffatt@dehavilland.com
From:
Company:
Phone: Extn:
Facsimile: Date:
Email:
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
Email PDF to:
george.moffatt@dehavilland.com

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