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S . B . 8 --- 2 7 --- 1 2 2 Page 1 of 1218 Jul 2019 BM
SERVICE BULLETIN ATA SYSTEM: 2731 NUMBER: 8- - -27- - -122
DE HAVILLAND AIRCRAFT OF CANADA LIMITED (DHC) CONSIDERS
THIS SERVICE BULLETIN TO BE PARTICULARL Y SIGNIFICANT AND
URGES OPERATORS TO PROMPTL Y EVALUATE THE CONTENTS SUBJECT : Flight Controls - - - Elevator System and Inboard Secondary Hinge Attachment - - - Special Inspection of Barrel Nuts
1. PLANNING INFORMA TION A. Effectivity Aircraft Affected:
In- - -Service: DHC- - -8 Aircraft Models 102, 103, 106, 201, 202, 301, 311, 314 and 315 Serial Numbers 003 thru 672.
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:
None
S E R V I C E B U L L E T I N 8 --- 2 7 --- 1 2 2 S . B . 8 --- 2 7 --- 1 2 2 Page 2 of 1218 Jul 2019 BM B. Reason Problem: Corrosion or cracks have been reported in DSC228- - -type barrel nuts in the fleet. T welve DSC228- - -5 barrel nuts are installed in the elevator structure assembly.
Solution: This service bulletin provides the instructions to do a detailed visual inspection of the barrel nuts DSC228- - -5 used in the elevator structure assembly to look for any corrosion or cracks.
This service bulletin also provides th e necessary instructions if damage is found. If required, barrel nuts DSC228- - -5 are to be replaced with B0203073- - -5.
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 through each main gear and main gear door mechanism
- - - Applicable elevator access panels are removed
- - - Six barrel nuts in each of the LH and RH control attachment fittings are inspected
- - - If any barrel nut is cracked or corroded, the elevator is removed, the barrel nut and associated hardware are replaced, and the elevator is installed
- - - Applicable elevator access panels are installed
- - - Close out.
D. Compliance DE HAVILLAND AIRCRAFT OF CANADA LIMI TED highly recommends this special inspection service bulletin be incorporated at the earliest opportunity unless otherwise directed by the operator’s airworthiness authority.
Transport Canada Airworthiness Directive Pending.
S E R V I C E B U L L E T I N 8 --- 2 7 --- 1 2 2 S . B . 8 --- 2 7 --- 1 2 2 Page 3 of 1218 Jul 2019 BM 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 4.00 to 13.00 man - - -hours to complete this service bulletin.
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 1.00 Procedure (Inspection) 2.00 Procedure (Rectification) 8.00 T e s t/R T S 1.00 Close- - -Out 1.00 NOTE: T est/RTS man- - -hours is required, only if barrel nut was removed or replaced.
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 The parts and materials required are listed in Paragraph 2.A. The parts required may be either furnished or fabricated from the operator’s existing stock, purchased as single items from DHC or purchased directly from industry sources.
S E R V I C E B U L L E T I N 8 --- 2 7 --- 1 2 2 S . B . 8 --- 2 7 --- 1 2 2 Page 4 of 1218 Jul 2019 BM See the contact information below.
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 Not affected J. Electrical Load Data Not affected K. Publications Affected Aircraft Illustrated Parts Catalog PSM 1- - -8- - -4 and......................
P S M 1 --- 8 2 --- 4 a n d P S M 1 --- 8 3 --- 4 Modifications Manual PSM 1- - -813- - -12................................
S E R V I C E B U L L E T I N 8 --- 2 7 --- 1 2 2 S . B . 8 --- 2 7 --- 1 2 2 Page 5 of 1218 Jul 2019 BM L. References The initial issue of this service bulletin was prepared to the engineering drawings and related data that follows:
PCA 08235 Revision 0 (for internal reference only) Transport Canada Airworthiness Directive Pending.
2. MATERIAL INFORMA TION A. Parts Required Per Aircraft
(1) Detailed Parts List:
Quantity Per Aircraft Part Number Description Remarks 12 12 8 4 12 B0203073- - -5 NAS578- - -5A MS21250H05010 MS21250- - -05010 MS20002C5 Barrel Nut Retainer Bolt Bolt Washer NOTE: This service bulletin is self- - -contained. No drawings will be supplied.
(2) In addition to the above part(s), the f ollowing consumable products 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 “REF ITEM” identification number that is used to identify a particular recommended product, the specifications and the trade names any of which can be used u n l e s s s p e c i f i e d o t h e r w i s e ( r e f e r t o P S M 1 --- 8 --- 2 , 1 --- 8 2 --- 2 o r 1 --- 8 3 --- 2 A i r c r a f t Maintenance Manual (AMM) Chapter 51- - -31- - -00 CONSUMABLE MATERIALS - - - MAINTENANCE PRACTICES).
S E R V I C E B U L L E T I N 8 --- 2 7 --- 1 2 2 S . B . 8 --- 2 7 --- 1 2 2 Page 6 of 1218 Jul 2019 BM REF ITEM Qty. Per Aircraft Description Remarks 07- - -01 1/2 Quart F 1 3 C o a t i n g --- Compound, Corrosion Preventive, (hard, soft film, moisture displacing) F13, Grade 2 14- - -06 As Required Lockwire - - - 0.032 in.
MS20995C32 B. Parts Required to Modify Spares None C. Special T ools and Equipment Required Borescope equivalent to: ITI (Instrument T echnology Inc) Model 123010- - -40, (40 degrees with right angle adapter, 10 mm diameter 60 cm long) 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 DSC228- - -5 Barrel Nut 12 C DIS B0203073- - -5 S 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.
S E R V I C E B U L L E T I N 8 --- 2 7 --- 1 2 2 S . B . 8 --- 2 7 --- 1 2 2 Page 7 of 1218 Jul 2019 BM 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 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 .
S E R V I C E B U L L E T I N 8 --- 2 7 --- 1 2 2 S . B . 8 --- 2 7 --- 1 2 2 Page 8 of 1218 Jul 2019 BM
(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 P S M 1 --- 8 --- 2 o r 1 --- 8 2 --- 2 o r 1 --- 8 3 --- 2 Chapters 12 and 24).
(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.
B. Procedure
(1) Remove elevator access panels 325BT , 325CT , 333BBL and 343BBR. Refer to applicable instructions in AMM 06- - -40- - -10- - -00 (S100 and S300) or AMM 06- - -41- - -00- - -00 (S200).
(2) Examine both upper and lower visible ends of the barrel nuts (six barrel nuts in each of the LH and RH control attachment fittings). Make sure that there are no cracks, corrosion or other types of damages.(refer to Figure 1).
NOTE: Use a light source, inspection mirror, magnifying glass and/or borescope as necessary.
(3) If cracks, corrosion, or other damage are found in any barrel nut:
(a) Remove the elevator assembly for access. Refer to AMM 27- - -32- - -11- - -02 (S100 and S300) or TASK 27- - -32- - -11- - -000- - -801 (S200).
(b) Replace existing barrel nut DSC228- - -5 with new barrel nut B0203073- - -5, new retainer NAS578- - -5A, new bolts MS21250H05010 or MS21250- - -05010, and new washer MS20002C5. Bolts MS21250H05010 are to be torqued to 200 in. lbs. Coat under washer, shank of bolt, and seating surface of barrel nut with F13, Grade 2 (07- - -01). Refer to Figure 2.
Wire lock the MS21250H05010 bolts per AMM 20- - -09- - -10 (S100 and S300) or AMM TASK 20- - -09- - -10- - -400- - -801 (S200).
S E R V I C E B U L L E T I N 8 --- 2 7 --- 1 2 2 S . B . 8 --- 2 7 --- 1 2 2 Page 9 of 1218 Jul 2019 BM
(c) Install the elevator assembly. Refer to AMM 27- - -32- - -11- - -02 (S100 and S300) or TASK 27- - -32- - -11- - -400- - -801 (S200).
(4) If no cracks, corrosion, or other damage is found in any existing barrel nuts DSC228- - -5, the undamaged barrel nuts and all other hardware will remain in service.
(5) Install elevator access panels 325BT , 325CT , 333BBL and 343BBR. Refer to applicable instructions in AMM 06- - -40- - -10- - -00 (S100 and S300) or AMM 06- - -41- - -00- - -00 (S200).
C. Close Out
(1) Remove all tools and equipment from the work area.
(2) Complete the enclosed inspection form (Appendix A) with inspection results and submit to the T echnical Help Desk.
(3) On completion of this service bulletin, make the following entry in the appropriate logbooks: “Service Bulletin 8- - -27- - -122 {Flight Controls - - - Elevator System and Inboard Secondary Hinge Attachment - - - Special Inspection of Barrel Nuts} accomplished.”
SERVICE BULLETIN 8-27-122 00 NOTE Left side shown.
Right side opposite.
MS21250-05010
BOLT WASHER HINGE MS21250H05010 BOLT SPAR
WASHER (REF) VASI BARREL NUT WASHER
RETAINER MS21250H05010
BOLT BARREL NUT
BRACKET RETAINER BARREL
NUT BARREL
CONTROL ATTACHMENT NUT
FITTING RETAINER Elevator System and Inboard Secondary Hinge Attachment Figure 1 S.B. 8-27-122 18 Jul 2019 Page 10 of 12 BM
SERVICE BULLETIN 8-27-122
UNDER BOLT HEAD
UNDER WASHER
ON BOLT SHANK
ON SEATING
SURFACE dsb8 27122 003.da. nn. jun03/2019 Application of F13 Type2 Compound to Bolt and Barrel Nut Figure 2 S.B. 8-27-122 18 Jul 2019 Page 11 of 12 BM
SERVICE BULLETIN 8-27-122
APPENDIX A Date of inspection:
Elevator Assembly, Left Side Aircraft Hours Cycles Hinge Barrel Nut Bracket Barrel Nut S/N Barrel Nut Barrel Nut Barrel Nut Barrel Nut Cracked Corroded Cracked Corroded Yes No Yes No Yes No Yes No Date of inspection:
Elevator Assembly, Right Side Aircraft Hours Cycles Hinge Barrel Nut Bracket Barrel Nut S/N Barrel Nut Barrel Nut Barrel Nut Barrel Nut Cracked Corroded Cracked Corroded Yes No Yes No Yes No Yes No dsb8_27122_002.dg. nn, apr22/2019 Inspection Form S.B. 8-27-122 18 Jul 2019 Page 12 of 12 BM