# Bombardier Service Bulletin 84-52-88

Copy: No revision named ("SB 84-52-88"), 18 pages: PDF https://openairdocs.org/files/sha256/bd/2a/bd2a4507b29048d08544a5200521feae0020f68197e7eed5904f7f4d32e1fcea; text https://openairdocs.org/service-documents/bombardier/sb-84-52-88/file/bd2a4507b290.md. Rights: © Bombardier Inc. Filed by the FAA in regulations.gov docket FAA-2017-0621; AD 2018-02-16 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: 84-52-88
- Page: https://openairdocs.org/service-documents/bombardier/sb-84-52-88

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

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

- [AD 2018-02-16](https://openairdocs.org/ad/2018-02-16.md), effective Mar 5, 2018: No revision named

Also cited in [1 proposed AD](https://openairdocs.org/service-documents/bombardier/sb-84-52-88/proposed.md).

## Text (18 pages)

Rights: © Bombardier Inc. Filed by the FAA in regulations.gov docket FAA-2017-0621; AD 2018-02-16 incorporates this document by reference. Not covered by OpenAirDocs’ CC0 dedication. Some pages are OCR from a scan. OCR can misread letters and numbers. Each page's text from the PDF; open the PDF at a page with #page=N.

### Page 1

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SERVICE BULLETIN
Customer
Support
ATA SYSTEM: 5200 NUMBER: 84- - -52- - -88
BOMBARDIER AEROSPACE REGIONAL AIRCRAFT CONSIDER THIS
SERVICE BULLETIN TO BE PARTICULARL Y SIGNIFICANT AND
URGE OPERATORS TO PROMPTL Y EVALUATE THE CONTENTS
SUBJECT : Doors - - - Bearings Corrosion on Forward Emergency Exit T ype I Door,
Aft Service Door and Aft Entry Door - - - Inspection and Rectification
1. PLANNING INFORMA TION
A. Effectivity
Aircraft Affected:
In- - -Service: DHC- - -8 Aircraft Models 401 and 402 Serial Numbers 4001,
4003 thru 4488.
NOTE: This inspection and rectification service bulletin is not applicable on
aircraft with ModSum IS4Q5200050 incorporated.
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.

### Page 2

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Spares Affected:
None
B. Reason
Problem: Multiple events of translating doors being difficult to open have been
reported.
Cause: Investigations found that translating doors become difficult to open
because of corroded roller bearings on the lift and latch shaft.
Solution: This service bulletin is being issued to do an inspection of the roller
bearings on the lift and latch shaft of the forward emergency exit T ype I
door, aft entry door and aft service door for evidence of corrosion. If any
corrosion is found the affected bearing is replaced and corrosion inhibiting
compound (CIC) is applied.
C. Description
The procedures in this service bulletin give the instructions to do the tasks that follow:
- - - 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
- - - access to the roller bearings on the lift and latch shaft of the forward emergency exit
T ype I door (if installed), aft entry door and aft service door is gained
- - - the roller bearings are inspected for corrosion
- - - if corrosion is not found, corrosion inhibiting compound (CIC) is applied to the roller
bearings
- - - if corrosion is found on the roller bearings, the roller bearings are replaced and CIC
is applied
- - - an operational test of the applicable door is done
- - - close out.

### Page 3

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D. Compliance
Bombardier Inc. highly recommend the accomplishment of this inspection and
rectification service bulletin 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
# 9 3 --- Q --- 0 2 .
This service bulletin does not affect Airworthiness Limitations (AWLs) or Damage
T olerance Inspections (DTIs).
F. M a n p o w e r
It will take an estimated 5.00 man- - -hours per door to complete. The breakdown of the
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 0.50
Procedure: Part A
Part B
1.00
2.50
T e s t/R T S 0.50
Close- - -Out 0.50
This estimate is for direct labour done by an experienced crew and it does not
include, planning, familiarization, cure tim e, part fabrication, tool acquisition or lost
time.
G. Material - - - Price and Availability
None

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H. T ooling - - - Price and Availability
None
I. Weight and Balance
Not affected
J. Publications Affected
None
K. References
The initial issue of this service bulletin was prepared to the engineering drawings and
related data that follows:
PCA 45273 Revision 3 (for internal reference only)
Transport Canada Airworthiness Directive Pending.
2. MATERIAL INFORMA TION
A. Parts Required Per Aircraft
(1) The consumable material that follows is 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.
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).

### Page 5

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Consumable
Product ID
Number
Qty. Per Aircraft Description Remarks
07- - -01 3o z . Compound, F13
Coating
MIL- - -PRF- - -16173
B. Parts Required to Modify Spares
None
C. Special T ools and Equipment Required
None
D. Existing Parts Accountability
None
3. ACCOMPLISHMENT INSTRUCTIONS
A . J o b S e t --- U p
(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 the nose gear ground lock is engaged.
(3) Make sure that lock pins are installed through each main gear and main gear
door mechanism.
(4) Set wheel chocks in front and behind the landing gear tires.
(5) Remove the related door surrounds and liners from forward emergency exit T ype
I door (if installed), aft entry door and aft service door to gain access to the the
lift and latch shaft assembly (refer to applicable instructions in AMM TASK
2 5 --- 2 6 --- 1 6 --- 0 0 0 --- 8 0 2 o r A M M T A S K 2 5 --- 2 6 --- 2 1 --- 0 0 0 --- 8 0 1 o r A M M T A S K
25- - -26- - -26- - -000- - -801).
(6) Remove the access panels (refer to Figures 1 and 2). Keep screws for
re- - -installation.

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B. Procedure
Part A - - - Inspection of the Forward Emer gency Exit T ype I Door (if installed), Aft
Entry Door and Aft Service Door
(1) Do a Detailed Visual Inspection (DVI) of the roller bearings on the lift and latch
shaft in each door (refer to Figures 4, 5 and 6) for any signs of corrosion and for
condition of the bearings. Check that the seals are intact and that there is no sign
of lubricant loss.
(2) If the findings in step (1) above show evidence of corrosion, seal damage or loss
of lubricant, go to Part B - - - Rectificationbelow.
(3) If no evidence of corrosion, seal damage or loss of lubricant is found on the
bearings, clean the area and bearings and apply CIC (07- - -01) (refer to applicable
instructions in AMM TASK 51- - -25- - -01- - -390- - -801).
(4) Go to C. Close Out .
P a r t B ---Rectification
(1) Remove the lift and latch mechanism from forward emergency exit T ype I door (if
installed), aft entry door and aft service door (refer to applicable instructions in
A M M TA S K 5 2 --- 2 4 --- 1 1 --- 0 0 0 --- 8 0 1 o r A M M TA S K 5 2 --- 1 2 --- 1 1 --- 0 0 0 --- 8 0 1 o r A M M
TASK 52- - -41- - -11- - -000- - -801).
(2) Remove the support assemblies as follows (refer SRM Chapter 51- - -40- - -15,
F i g u r e s2 ,3 ,4a n d5 ) .
(a) Remove attaching rivets M7885/6- - -4- - -04 and B0205018AD4.
(b) Remove Hi- - -Lites B0206001AG5- - -3 and discard.
(c) On the Fwd Emergency Exit T ype I Door (if installed) and Aft Service Door,
remove support assemblies 85217721- - -002, 85217722- - -002, 85217722- - -001
and 85217723- - -002 and shims CSP469B- - -160- - -060 and
CSP469B- - -265- - -090.

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(d) On the Aft Entry Door, remove support assemblies 85217723- - -001,
85217722- - -002, 85217722- - -001 and 85217721- - -001 and shims
CSP469B- - -160- - -060 and CSP469B- - -265- - -090.
(3) Remove the existing roller bearing MS27646- - -39 from each support assembly
(refer to applicable instructions in AMM TASK 20- - -10- - -40- - -000- - -802).
(4) Clean the area and apply CIC (07- - -01) on the support assembly (refer to applicable
instructions in AMM TASK 51- - -25- - -01- - -390- - -801).
(5) Discard the corroded bearing and install new bearing MS27646- - -39 onto the
support assembly (refer to applicable instructions in AMM TASK
20- - -10- - -40- - -400- - -802).
(6) Apply CIC (07- - -01) to the bearing (refer to applicable instructions in AMM TASK
51- - -25- - -01- - -390- - -801).
(7) Install the support assemblies with new shims CSP469B- - -160- - -060 and
CSP469B- - -265- - -090 using rivets M7885/6- - -4- - -04 and B0205018AD4 and new
Hi- - -Lites B0206001AG5- - -3 (refer to Figure 3 and applicable instructions in SRM
C h a p t e r 5 1 --- 4 0 --- 1 5 ) .
(8) Install the lift and latch mechanism onto each door structure assembly (refer to
applicable instructions in AMM TASK 52- - -12- - -11- - -400- - -801 or AMM TASK
52- - -24- - -11- - -400- - -801 or AMM TASK 52- - -41- - -11- - -400- - -801).
C. Close Out
(1) Remove all tools and equipment from the work area.
(2) Make sure the access panels are installed (refer to Figures 1 and 2).
(3) Do an operational test of the affected translating door (refer to applicable
instructions in AMM TASK 52- - -12- - -00- - -710- - -802 or AMM TASK
52- - -24- - -00- - -710- - -801 or AMM TASK 52- - -41- - -00- - -710- - -801).
(4) Install door surrounds and liners (refer to applicable instructions in AMM TASK
2 5 --- 2 6 --- 1 6 --- 4 0 0 --- 8 0 1 o r A M M T A S K 2 5 --- 2 6 --- 2 1 --- 4 0 0 --- 8 0 1 o r A M M T A S K
25- - -26- - -26- - -400- - -801).

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(5) On completion of this service bulletin, make the following entry in the appropriate
logbooks: “Service Bulletin 84- - -52- - -88 (i.e. Doors - - - Bearings Corrosion on
forward Emergency Exit T ype I Door, Aft Service Door and Aft Entry Door
Inspection and Rectification) accomplished.”

### Page 9 (OCR)

SERVICE BULLETIN 84-52-88
ACCESS PANEL
SUPPORT ASSY
SCREW
MS27039-0810
ACCESS PANEL
SCREW
MS27039-0810
Support Assembly Access Panels - Typical
Figure 1
14 Apr 2016  S.B. 84-52-88
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NB

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Lift and Latch Mechanism - - - T ypical
Figure 2
H I --- L I T E S
B0206001AG5- - -3
ACCESS PANEL ACCESS PANEL
LIFT AND LATCH MECHANISM
SCREW
MS27039- - -0810
SCREW
MS27039- - -0810
COUNTERBALANCE SPRINGS

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L
L
DOOR
(TYPICAL)
RIVET
M7885/6- - -4- - -04
RIVET
M7885/6- - -4- - -04
SUPPORT ASSY
85217721- - -002*
SUPPORT ASSY
85217722- - -002
SUPPORT ASSY
85217722- - -001
SUPPORT ASSY
85217723- - -002*
Support Assembly Installation - - - T ypical
F i g u r e3( S h e e t1o f3 )
85217723- - -001**
85217721- - -001**
NOTE: *APPLICABLE ON FWD EMERGERGENCY EXIT TYPE I DOOR AND AFT SERVICE DOOR
**APPLICABLE ON AFT ENTRY DOOR.

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DOOR
SUPPORT ASSY
85217722- - -001
HI- - -LITE
B0206001AG5- - -3
SHIM
CSP469B- - -160- - -060
SUPPORT ASSY
85217722- - -002
RIVET
B0205018AD4
SHIM
CSP469B- - -160- - -060
SUPPORT ASSY
85217722- - -002
DOOR
RIVET
B0205018AD4
SHIM
CSP469B- - -265- - -090
SHIM
CSP469B- - -265- - -090
HI- - -LITE
B0206001AG5- - -3
Support Assembly Installation - - - T ypical
F i g u r e3( S h e e t2o f3 )

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SHIM
CSP469B- - -265- - -090
HI- - -LITE
B0206001AG5- - -3
SUPPORT ASSY
85217723- - -002*
TRANSLATING DOOR
SHIM
CSP469B- - -160- - -060
SUPPORT ASSY
85217723- - -002*
RIVET
B0205018AD4
Support Assembly Installation - - - T ypical
F i g u r e3( S h e e t3o f3 )
85217721- - -001**
85217721- - -001**
NOTE: *APPLICABLE ON FWD EMERGENCY EXIT TYPE I DOOR AND AFT SERVICE DOOR
**APPLICABLE ON AFT ENTRY DOOR.

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Roller Bearings - - - Aft Passenger Door
Figure 4
TORQUE TUBE
B
ROLLER BEARING
ROLLER BEARING
ROLLER BEARING
B
LATCH SHAFT SUPPORT ASSY
LATCH SHAFT
SUPPORT ASSY
MS27646- - -39
MS27646- - -39
MS27646- - -39

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Roller Bearings - - - Forward Emergency Exit T ype I Door
Figure 5
TORQUE TUBE
B
ROLLER BEARING
ROLLER BEARING
ROLLER BEARING
ROLLER BEARING
LATCH SHAFT SUPPORT ASSY
LATCH SHAFT
SUPPORT ASSY
MS27646- - -39
MS27646- - -39
MS27646- - -39
MS27646- - -39

### Page 16

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Roller Bearings - - - Aft Service Door
Figure 6
B
TORQUE TUBE
ROLLER BEARING
ROLLER BEARING
ROLLER BEARING
ROLLER BEARING
LATCH SHAFT SUPPORT ASSY
LATCH SHAFT
SUPPORT ASSY
MS27646- - -39
MS27646- - -39
MS27646- - -39
MS27646- - -39

### Page 17

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 18

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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