Revision ‘B’ 11 Feb 2014 DHC ---8 (DASH 8) SERVICE BULLETIN 84 ---27 ---44
Flight Controls --- Rudder Control Surfaces --- Fore Rudder --- Special Inspection for Correct Installation of Bearings This page transmits Revision ‘B’ of Service Bulletin 84 ---27 ---44, pages 1 thru 16, dated 11 Feb 2014. This service bulletin is re ---issued in its entirety for the reasons that follow: --- the PLANNING INFORMATION section D. Compliance on page 3 is revised to add Transport Canada Airworthiness Directive CF ---2013 ---34. --- the PLANNING INFORMATION section L. Referenceson page 4 is revised to show Revision ‘B’ of this service bulletin was prepared to the related data that follows and also to add Transport Canada Airworthiness Directive CF ---2013 ---34. --- theACCOMPLISHMENT INSTRUCTIONS section B. Procedure on page 8 NOTE is clarified. --- theACCOMPLISHMENT INSTRUCTIONS section C. Close Outon page 9 step (5) is revised to correct the referenced task number. Was TASK 27 ---20 ---01 ---710 ---802 now TASK 27 ---20 ---00 ---710 ---802. The Compliance in the previous issue 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 ---27 ---44 Revision A and replace with attached. Previous issue of Service Bulletin 84 ---27 ---44: Initial issue --- Pages 1 thru 14 dated 13 Apr 2009 Rev A --- Pages 1 thru 16 dated 10 Jun 2009

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S.B. 84 ---27 ---44 Page 1 of 16 13 Apr 2009 Revision ‘B’ 11 Feb 2014 MD 

# SERVICE BULLETIN Customer Support

ATA SYSTEM: 2723 NUMBER: 84 ---27 ---44


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

SUBJECT: Flight Controls --- Rudder Control Surfaces --- Fore Rudder --- Special Inspection for Correct Installation of Bearings

1. PLANNING INFORMA TION
A. Effectivity Aircraft Affected: In ---Service: DHC ---8 Aircraft Models 401 and 402 Serial Numbers 4166 thru 4175. Production: A line check is done before delivery of DHC ---8 Models 401 and 402 Serial Number 4176 and subsequent per Line Check 37422.
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.

### SERVICE BULLETIN 84 ---27 ---44

S.B. 84 ---27 ---44 Page 2 of 16 13 Apr 2009 Revision ‘B’ 11 Feb 2014 MD Spares Affected: None B. Reason Problem: Bombardier production line inspection have reported that (upper and/or lower) installed bearings in the fore rudder have migrated from their housing on several aircraft. Cause: The bearings had not been properly installed with adhesive (Loctite Grade AA ) and sealed per engineering requirements. Solution: A special inspection and if required rectification is accomplished to confirm that affected bearings are correctly installed and sealed. C. Description The procedures in this service bulletin give the instructions to do the tasks that follow: --- #1 and #2 hydraulic systems are pressurized --- the flaps are set to greater than 5 degrees --- the rudder is swung full trailing ---edge left and held --- #1 and #2 hydraulic systems are de ---pressurized --- safety stands are placed behind the rudder --- access panels 323CR and 323BR are removed from the fore rudder --- rivets are drilled off and cover 85547207 ---103 is removed, if required, to proof load test installed bearing --- PCU actuator rod is detached from existing fore rudder hinge bracket assembly --- existing bearings are then visually inspected and then proof load tested, if the bearing passes proof load, no additional action is required --- PART A INSPECTION of the Proceduressection gives the instructions to inspect the bearing for correct installation in the fore rudder --- PART B RECTIFICATION of the Proceduressection gives the instructions for removal of bearings, inspection of the existing bore, installation of bearing with adhesive Loctite Grade AA, proof load bearing test and the application of sealant to the existing bearings in the fore rudder --- the PCU actuator rod is attached to the existing fore rudder hinge bracket assembly using retained hardware --- cover 85547207 ---103 is installed to fore rudder with rivets

### SERVICE BULLETIN 84 ---27 ---44

S.B. 84 ---27 ---44 Page 3 of 16 13 Apr 2009 Revision ‘B’ 11 Feb 2014 MD --- previously removed access panels are installed with retained hardware --- an operational check of the rudder system is done --- close out. D. Compliance Bombardier Inc. recommend that the special inspection/rectification be incorporated at the earliest opportunity unless otherwise directed by the operator’s airworthiness authority. Transport Canada Airworthiness Directive CF ---2013 ---34. 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. F. Manpower PART A --- Special Inspection for Correct Installation of Bearings --- Fore Rudder It will take an estimated 6.50 man ---hours to complete PART A of the ACCOMPLISHMENT instructions in this service bulletin. The breakdown of man ---hours is shown in the table that follows: TASK MAN ---HOURS Job Set ---Up 2.00 Procedure in Part A 1.50 Test / RTS 1.00 Close ---Out 2.00 PART B --- Rectification Procedure for Incorrect Installation of Bearing --- Fore Rudder It will take an estimated 8.0 man ---hours to complete PART B of the ACCOMPLISHMENT instructions in this service bulletin. The breakdown of man ---hours is shown in the table that follows: TASK MAN ---HOURS Job Set ---Up 2.00 Procedure in Part B 3.00 Test / RTS 1.00 Close ---Out 2.00

### SERVICE BULLETIN 84 ---27 ---44

S.B. 84 ---27 ---44 Page 4 of 16 13 Apr 2009 Revision ‘B’ 11 Feb 2014 MD G. Material --- Price and Availability None H. Tooling --- Price and Availability None I. Weight and Balance None
J. Electrical Load Data Not affected
K. Publications Affected None
L. References Revision ‘B’ of this service bulletin was prepared to the related data that follows: PCA 42445 Revision --- (for internal reference only) Transport Canada Airworthiness Directive CF ---2013 ---34.
2. MATERIAL INFORMA TION
A. Parts Required Per Aircraft None

NOTE: This service bulletin is self ---contained (illustrated). No drawings will be supplied.
(1) 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 400 Series Aircraft, in Consumable Products Manual PSM 1 ---84 ---18.

### SERVICE BULLETIN 84 ---27 ---44

S.B. 84 ---27 ---44 Page 5 of 16 13 Apr 2009 Revision ‘B’ 11 Feb 2014 MD Part Number Qty. Per Aircraft Description Remarks MIL ---R ---81533 1 Ounce Solvent Trichloroethane, 1,1,1 or DHMS S5.01 Class 2 1 Ounce Solvent Dynamold, Spec AMS 3167 MIL ---S ---22473 1 Ounce Sealant Loctite, Grade AA Loctite 7387 1 Ounce Sealant,Activator Loctite, Activator, Grade N DHMS S3.01,Type II, Class B 1 Ounce Sealant PR1776M B1/2 or PR1776M B2 As Required Wiper Cloth White, Cotton Lint ---Free Cloth 1 Marker Red Marker Martex Corp. B0205018AD4 ---4S 8 Rivet
B. Parts Required to Modify Spares None C. Special Tools and Equipment Required

Part Number Description Remarks Dillon Model U 30354 ---0058 or Equivalent Force Gage Force Gage See Note 1 C ---Clamp NAS43HT10 ---8 Spacer (Qty 1) See Note 2 NAS43HT14 ---8 Spacer (Qty 1) See Note 2 AN970 ---4 Washer NOTE 1: Commercially available support hardware for proof loading may be substituted for equivalent to suit individual force gage geometry. NOTE 2: In the event that spacers listed are difficult to procure, operators are permitted to locally manufacture spacers if required. Refer to Figure 6

### SERVICE BULLETIN 84 ---27 ---44

S.B. 84 ---27 ---44 Page 6 of 16 13 Apr 2009 Revision ‘B’ 11 Feb 2014 MD for equivalent spacer dimensions and material specifications. D. Existing Parts Accountability None 3. ACCOMPLISHMENT INSTRUCTIONS A. Job Set ---Up

WARNING: MAKE SURE THAT PERSONS AND EQUIPMENT ARE CLEAR OF THE MOVEMENT OF FLIGHT CONTROL SURFACES. MOVEMENT OF THE FLIGHT CONTROL SURFACES CAN CAUSE INJURIES TO PERSONS AND DAMAGE TO THE EQUIPMENT. (1) Pressurize # 1 and # 2 hydraulic systems. Refer to Aircraft Maintenance Manual PSM 1 ---84 ---2, TASK 29 ---00 ---00 ---863 ---801. (2) Set flaps to greater than 5 degrees. (3) Apply rudder pedal full trailing ---edge left and hold. (4) De ---pressurize #1 and #2 hydraulic systems. Refer to Aircraft Maintenance Manual PSM 1 ---84 ---2, TASK 29 ---00 ---00 ---863 ---802. (5) Release rudder pedal and make sure no further pedal input is applied. The rudder should remain in the deflected left position. (6) Placard and select all aircraft electrical power to OFF. Obey all relevant WARNINGS and CAUTIONS detailed in Maintenance Manual PSM 1 ---84 ---2. Refer to Aircraft Maintenance Manual PSM 1 ---84 ---2, TASK 24 ---00 ---00 ---861 ---802. (7) Install workstands on both sides of the rudder to safely reach the center main hinge fittings as required. Make sure the workstands are electrically grounded. WARNING: BE SURE THAT THE HYDRAULIC PRESSURE IS OFF, AND THAT THERE IS NO PRESSURE IN THE HYDRAULIC SYSTEM. IF YOU DO NOT DO THIS YOU CAN INJURIES TO PERSONS AND DAMAGE TO THE EQUIPMENT. (8) Remove and retain fore rudder hinge bracket assembly access panels 323 CR and 323 BR, (RHS) and mounting hardware. Refer to Figure 1. (9) Carefully drill off rivets B0205018AD4 ---4S attaching cover 85547207 ---103 to fore rudder. Do not elongate rivet holes or damage countersink. Remove cover 85547207 ---103 to allow proof load tool to access fore rudder hinge bracket assembly 85547217 ---001 and ---002. Refer to Figure 2.

### SERVICE BULLETIN 84 ---27 ---44

S.B. 84 ---27 ---44 Page 7 of 16 13 Apr 2009 Revision ‘B’ 11 Feb 2014 MD NOTE: The skin consists of three parts, cover 85547207 ---103, Rib 85547208 ---103 and shim CSP 471 ---160 ---030 ---070 ---048. (10) Disconnect each rudder PCU rod from the hinge bracket assembly as follows : (a) Remove and discard the cotter pin MS24665 ---302. Refer to Figure 3. (b) Remove and retain nut MS1414L6 and washer AN960D616L. (c) Remove and retain the bolt NAS6706D14 from the end of the PCU actuator rod and fore rudder hinge bracket assembly.
B. Procedure

NOTE: Instructions in PART A and PART B are given for upper hinge bracket assembly 85547217 ---001. Repeat procedure in PART A and PART B for lower bracket assembly 85547217 ---002.
PART A INSPECTION (1) Set up proof load tester, Dillon Model U 30354 ---0058 or equivalent force gage and C ---clamp, to the fore rudder hinge bracket assembly 85547217 ---001. Refer to Figure 5. (2) Proof load existing bearing DSC8 ---6 in ---situ to 132 lbs. Apply load by slowly tightening C ---Clamp. During proof load testing, any slippage or freeplay (relative movement between the bearing and fitting) is deemed as unacceptable. (3) If bearing fails proof load test, refer to PART B RECTIFICATION section.
NOTE: Make sure spacer, (support) NAS43HT10 ---8 or equivalent, contacts bearing race only .

NOTE: Make sure spacer, (support) NAS43HT14 ---8 or equivalent, contacts fitting 85574217 ---001 and washer, (support) AN970 ---4 on C ---Clamp. (4) If existing bearing passes the proof load test, no further additional action is required. Refer to C. Close Outsection. (5) Inspect area adjacent to the proof load tested bearings for a small red dot, if no dot is present, identify area using a Dalo marker or equivalent paint marker. Refer to Figure 5. (6) If bearings have not been sealed, apply sealant DHMS S3.01, Type II, Class B between the outside circumference of the installed bearing (both sides) and fore rudder hinge bracket assembly 85547217 ---001.

### SERVICE BULLETIN 84 ---27 ---44

S.B. 84 ---27 ---44 Page 8 of 16 13 Apr 2009 Revision ‘B’ 11 Feb 2014 MD NOTE: Do not allow sealant to enter bearings.
PART B RECTIFICA TION (1) If existing bearing fails proof load test, remove bearing DSC8 ---6 from fore rudder hinge bracket assembly 85547217 ---001. (2) Carefully remove sealant (if applicable) with a plastic or phenolic scraper from bearing and top/bottom surfaces of fore rudder hinge bracket assembly.
NOTE: Do not use metal scrapers to remove sealant. Metal scrapers will damage the surface. (3) Inspect bearing DSC8 ---6 for damage, corrosion and dimension conformity. Outside diameter of bearing should be 0.8120 to 0.8125 inch diameter.
NOTE: The existing bearings DSC8 ---6 may be reused if no damage, corrosion and dimensional non ---conformity is evident. (4) Inspect fitting bore of the fore rudder hinge bracket assembly 85547217 ---001 as follows: (a) Carefully inspect bore of the fore rudder hinge bracket assembly, using flashlight and inspection mirror, for damage, corrosion and dimension conformity. (b) If damage, corrosion or dimensional non ---conformity is evident, carefully ream the inside diameter with a 0.8140 inch diameter reamer. (c) If bore is worn or damaged beyond 0.8140 inch diameter, a repair disposition (RD) will be required from Bombardier. Contact the Technical Help Desk department. (5) Install new or existing DSC8 ---6 bearing into the fore rudder hinge bracket assembly 85547217 ---001 with sealant MIL ---S ---22473 as follows: (a) Solvent wipe the fitting bore of the fore rudder hinge bracket assembly and bearings with a clean, cotton lint ---free cloth dampened with solvent MIL ---R ---81533 or solvent DHMS S5.01, Class 2. Refer to Structural Repair Manual, PSM 1 ---84 ---3 , 51 --- 22 ---40, Loctite Sealant Bonding procedure. Refer to Figure 5.
NOTE: When cleaning sealed, grease lubricated bearings, make sure that no solvent enters the sealed bearing and contaminates the lubricant.

NOTE: Handle all clean parts with clean lint ---free cotton gloves.

### SERVICE BULLETIN 84 ---27 ---44

S.B. 84 ---27 ---44 Page 9 of 16 13 Apr 2009 Revision ‘B’ 11 Feb 2014 MD (6) Proof load installed bearings to 132 pounds with Dillon Model U 30354 ---0058 or equivalent force gage. Refer to Figure 5. (7) Identify proof loading test by applying a small red dot adjacent to the bearing using a Dalo marker or equivalent. (8) Seal the outer circumference of the installed bearing DSC8 ---6 to fore rudder hinge bracket assembly 85547217 ---001 (on both sides of installed bearing) with sealant DHMS S3.01, Type II, Class B. Refer to Figure 5.
NOTE: Do not allow sealant to enter bearings. (9) Identify fore rudder hinge bracket assembly 85547217 ---001 with “SB 84 ---27 ---44” in a suitable area using a thin permanent marker.
C. Close Out (1) Reconnect the rudder PCU rod to the hinge bracket. Install with retained bolt NAS6706D14, retained washers AN960D616L (one under bolt head), retained MS14144L6 nut and new cotter pin MS24665 ---302. Refer to Figure 3. (2) Make sure the shim CSP 471 ---160 ---030 ---070 ---048 is installed between the rib 85547208 ---103 and cover 85547207 ---103. Install cover 85547207 ---103 with rivets B0205018AD4 ---4S. Refer to Figure 2. (3) Install access panels 323CR and 323BR with retained hardware. (4) Remove all tools and equipment from the work area. (5) Do the operational check of the rudder control system. Refer to Aircraft Maintenance Manual, PSM 1 ---84 ---2, TASK 27 ---20 ---00 ---710 ---802. (6) On completion of this service bulletin, make the following entry in the appropriate logbooks: “Service Bulletin 84 ---27 ---44 Flight Controls --- Rudder Control Surfaces --- Fore Rudder --- Special Inspection for Correct Installation of Bearings accomplished”.

### SERVICE BULLETIN 84 ---27 ---44

S.B. 84 ---27 ---44 Page 10 of 16 13 Apr 2009 Revision ‘B’ 11 Feb 2014 MD Fore Rudder Access Panels Figure 1 FORE RUDDERmhwf1a01.cgm COVER 85547207 ---103 323CL

323BL 323CR

323BR

(REFERENCE) (REFERENCE) ACCESS PANEL

ACCESS PANEL Z107 110.031

ACCESS PANEL

ACCESS PANEL Z107 124.031

D B

### SERVICE BULLETIN 84 ---27 ---44

S.B. 84 ---27 ---44 Page 11 of 16 13 Apr 2009 Revision ‘B’ 11 Feb 2014 MD Removal/Installation of Cover Figure 2 COVER 85547207 ---103 RIB 85547208 ---103

SHIM CSP471 ---160 ---030 ---070 ---048 NOTE:

ACCESS PANEL 323CR

ACCESS PANEL 323BR COVER 85547207 ---103 CONSISTS OF RIB 85547208 ---103

RIVET B0205018AD4 ---4S AND SHIM CSP471 ---160 ---030 ---070 ---048

(QTY 8 REQUIRED) FORE RUDDER HINGE LINE

D Z107 110.031

124.031

Z107

ALL MEASUREMENTS ARE IN INCHES NOTE:

### SERVICE BULLETIN 84 ---27 ---44

S.B. 84 ---27 ---44 Page 12 of 16 13 Apr 2009 Revision ‘B’ 11 Feb 2014 MD Removal/Installation of PCU Rudder Actuator Rod Figure 3 BOLT NAS6706D14

PCU ACTUATOR ROD WASHER AN960D616L

NUT AN960D616L WASHER

MS14144L6 COTTER PIN MS24665 ---302 BEARING DSC8 ---6 FORE RUDDER HINGE BRACKET ASSEMBLY 85547217 ---001/ ---002 RUDDER PCU

B

### SERVICE BULLETIN 84 ---27 ---44

S.B. 84 ---27 ---44 Page 13 of 16 13 Apr 2009 Revision ‘B’ 11 Feb 2014 MD Installation/Removal of Bearing DSC8 ---6 Figure 4 BEARING DSC8 ---6

BEARING DSC8 ---6

FORE RUDDER HINGE BRACKET ASSEMBLY 85547217 ---001 FORE RUDDER

FORE RUDDER HINGE BRACKET ASSEMBLY 85547217 ---002 D

D

### SERVICE BULLETIN 84 ---27 ---44

S.B. 84 ---27 ---44 Page 14 of 16 13 Apr 2009 Revision ‘B’ 11 Feb 2014 MD MIL ---S ---22473

FITTING 85547217 ---001/ ---002 BEARING DSC8 ---6 INSTALL BEARING DSC8 ---6 WITH SEALANT PROOF MARK WITH DALO MARKER OR EQUIVALENT

BETWEEN FITTING AND THE OUTER CIRCUMFERENCE OF THE INSTALLED BEARING DSC8 ---6 (BOTH SIDES) APPLY SEALANT DHMS S3.01, TYPE II, CLASS B Proof Loading Bearing Test / Sealant Application Figure 5 PROOF LOAD BEARING DSC8 ---6 TO 132 POUNDS

FITTING BEARING DSC8 ---6 85547217 ---001/ ---002 DILLON MODEL U 30354 ---0058 FORCE GAGE OR EQUIVALENT C ---CLAMP

SPACER, (SUPPORT) NAS43HT14 ---8 OR EQUIVALENT

WASHER, (SUPPORT) AN970 ---4 OR EQUIVALENT

SPACER, (SUPPORT) NAS43HT10 ---8 OR EQUIVALENT PROOF LOAD BEARING TEST

APPLICATION OF ADHESIVE AND SEALANT TO BEARING 1

### SERVICE BULLETIN 84 ---27 ---44

S.B. 84 ---27 ---44 Page 15 of 16 13 Apr 2009 Revision ‘B’ 11 Feb 2014 MD ALLOY STEEL TUBING
NAS43HT --- (DIAMETER DASH NUMBER) --- (LENGTH DASH NUMBER) GENERALCODE MA TERIAL

10 0.120 0.927 0.735 0.765 0.627 0.677 14 0.130 0.985 1.015 0.877

NOTE: 1. ALL DIMENSIONS IN INCHES

Equivalent Spacer Dimensions and Material Specifications Figure 6 2. REMOVE ALL BURRS TO LENGTH 0.120 0.130

3. SPACERS ARE SUPPORT HARDWARE FOR PROOF LOADING. THEY ARE NOT PART OF THE AIRCRAFT. MIN TO MAX

4. LISTED DIMENSIONS ARE SUGGESTED DIMENSION TO SUIT DILLON MODEL U FORCE GAGE. IF ALTERNATE FORCE GAGE IS USED, OPERATORS ARE PERMITTED TO DEVIATE FROM LISTED DIMENSIONS TO SUIT INDIVIDUAL FORCE GAGE GEOMETRY.

### SERVICE BULLETIN 84 ---27 ---44

S.B. 84 ---27 ---44 Page 16 of 16 13 Apr 2009 Revision ‘B’ 11 Feb 2014 MD 

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