# Bombardier Service Bulletin 84-71-13 Copy: No revision named ("U.S. DOT/FAA - Service Information"), 18 pages: PDF https://openairdocs.org/files/sha256/05/78/05780b5c1a03b9733d3c287812bebf45b6ff4aaab869de54304b07975ccb8b7b; text https://openairdocs.org/service-documents/bombardier/sb-84-71-13/file/05780b5c1a03.md. Rights: © Bombardier Inc. Filed by the FAA in regulations.gov docket FAA-2011-1418; AD 2012-16-10 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: 84-71-13 - Page: https://openairdocs.org/service-documents/bombardier/sb-84-71-13 ## ADs that cite it (1) (OpenAirDocs) Newest first, with the revision each names, as OpenAirDocs read it from the AD's text. - [AD 2012-16-10](https://openairdocs.org/ad/2012-16-10.md), effective Sep 18, 2012: No revision named Also cited in [1 proposed AD](https://openairdocs.org/service-documents/bombardier/sb-84-71-13/proposed.md). ## Text (18 pages) Rights: © Bombardier Inc. Filed by the FAA in regulations.gov docket FAA-2011-1418; AD 2012-16-10 incorporates this document by reference. Not covered by OpenAirDocs’ CC0 dedication. This text is 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 (OCR) de HAVILLAND BOMBARDIER DASH8 SERVICE BULLETIN Customer. Support ATA SYSTEM: 7110 NUMBER: 84-71-13 BOMBARDIER AEROSPACE REGIONAL AIRCRAFT CONSIDER THIS SERVICE BULLETIN TO BE PARTICULARLY SIGNIFICANT AND URGES OPERATORS TO PROMPTLY EVALUATE THE CONTENTS SUBJECT: Powerplant - Lower Cowl Assembly - Re-Orientation and Clipping of the Forward and Mid Expandable Pin Lanyards - ModSum 4-113715 PLANNING INFORMATION A. Effectivity Aircraft Affected: In-Service: DHC-8 Aircraft Models 401 and 402 Serial Numbers 4001, 4003 thru 4354 and 4356 thru 4363. Production: ModSum 4-113715 will be installed before delivery on applicable DHC-8 Aircraft at Serial Number 4355 and 4364 and subsequent. 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 19 May 2011 S.B. 84-71-13 Page 1 of 18 VB ### Page 2 (OCR) SERVICE BULLETIN 84-71-13 B. Reason Problem: An operator has discovered signs of chafing on high pressure fuel lines. Cause: Cause of problem is attributed to a misinstallation of cowling pin lanyard on lower cowl assembly. Solution: ModSum 4-113715 provides instructions for the relocation of the lanyard/cowl attachment bolts and to provide clips for positive lanyard retention. Expectations of the modification is designed to minimize lanyard chafing on fuel line with the addition of the positive retention clips. 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 - work platforms are set up near the nacelles - the lower cowl is removed - existing bolts and washers attaching existing lanyards to the lower cowl are removed, lanyards are temporarily disconnected and existing bolt and washers are re-installed to their existing locations as required - existing lanyards are installed in new locations with the existing bolts and washers - existing rivets are removed as required and new spring clips are installed with new rivets at these locations - drilled rivet remnants and debris are carefully removed from the lower cowl assembly with a vacuum - the lower cowl is installed on the aircraft - work stands are removed from the nacelles - close out. D. Compliance Bombardier Inc. highly recommend that ModSum 4-113715 be incorporated at 19 May 2011 S.B. 84-71 - 13 Page 2 of 18 VB ### Page 3 (OCR) SERVICE BULLETIN 84-71-13 the earliest opportunity unless otherwise directed by the operator's airworthiness authority. 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 (DTS). Manpower It will take an estimated 3.0 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 0.50 Procedure 2.00 Test / RTS 0.00 Close-Out 0.50 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 parts) detailed in Paragraphs) 2.A. may be obtained from any Bombardier Aerospace Regional Aircraft authorized parts source. The price and availability will be quoted at the time of order. Bombardier Aerospace Customer Accounts Services Team (Mail Stop N11-32) 123 Garratt Blvd. Toronto Ontario Canada M3K-1Y5 Facsimile: (416) 375-3060 Telephone: (416) 375-3920 19 May 2011 S.B. 84-71 - 13 Page 3 of 18 VB ### Page 4 (OCR) SERVICE BULLETIN 84-71-13 H. Tooling - Price and Availability None I. Weight and Balance None J. Electrical Load Data Not affected K. Publications Affected Maintenance Manual . ........... PSM 1-84-2 Dash 8 Illustrated Parts Catalogue.................. PSM 1-84-4 ModSums Manual .. ............ PSM 1-84-12 References The initial issue of this service bulletin was prepared to the engineering drawings and related data that follows: ModSum 4-113715 Rev. 'E' ModSum 4Q113715 Rev. 'B' ModSum 4V113715 Rev. 'C' PCA 43181 Revision R2 (for internal reference only) GKN Aerospace Service Bulletin 1-71-3 dated 1st March 2011 Transport Canada Airworthiness Directive CF -2011-21 2. MATERIAL INFORMATION A. Parts Required Per Aircraft (1) Detailed Parts List: 19 May 2011 S.B. 84-71-13 Page 4 of 18 VB ### Page 5 (OCR) SERVICE BULLETIN 84-71-13 Quantity Part Number Description Remarks Per Aircraft CSP522-1 Clip (2) In addition to the above parts), the following material(s) 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 Consumable Products Manual PSM 1-84-18. Part Number Qty. Per Aircraft Description Remarks B0207004M5-6 4 Rivet Blind, 100 Degree Reduced Head M7885/8-5-04 4 Rivet Blind, Protruding Head DHMS S3.06 1/2 Ounce Type / Class C-80 Sealant TT-1-735 Grade A 1/4 Pint Solvent Isopropyl Alcohol B. Parts Required to Modify Spares None C. Special Tools and Equipment Required None D. Existing Parts Accountability None 19 May 2011/ S.B. 84-71 - 13 Page 5 of 18 VE ### Page 6 (OCR) SERVICE BULLETIN 84-71-13 3. ACCOMPLISHMENT INSTRUCTIONS A. Job Set-Up WARNING: DO NOT BREATHE THE FUMES FROM ISOPROPYL ALCOHOL. IT IS POISONOUS AND VERY FLAMMABLE. DO NOT GET IT ON YOUR SKIN OR IN YOUR EYES. USE ONLY IN AN AREA WITH CONTINUOUS AIRFLOW. TO KEEP ELECTRICAL CONTINUITY, GROUND ALL METAL CONTAINERS OF ISOPROPYL ALCOHOL, WEAR SAFETY CLOTHING, SPLASH GOGGLES AND A FACE SHIELD. (1) Placard and select all aircraft electrical power to OFF. Obey all relevant WARNINGS and CAUTIONS (refer to AMM TASK'S 24-00-00-861-802 and 24-00-00-910-801). (<) 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. Set up the work platforms or ladders as required to gain access to the nacelle lower cowl. Make sure the work platforms or ladders are electrically grounded. (5) Remove lower cowl from the aircraft. Refer to AMM PSM 1-84-2, TASK 71-10-16-000-801. B. Procedure Remove the two lanyards from their existing attachment points at the forward position of the lower cowl. Refer to the enclosed GN Aerospace Service Bulletin 1-71-23. (2) Remove bolts and washers and re-orientate position of the lanyards as required. Refer to the enclosed GN Aerospace Service Bulletin 1-71-23. (3) Apply sealant to bolts, washers and torque lanyard bolts as required. Refer to the enclosed GN Aerospace Service Bulletin 1-71-23. (4) Install new spring clips CSP522 on the butt strap at the forward end of the lower cowl. Refer to the enclosed GN Aerospace Service Bulletin 1-71-23. (5) Remove the remaining two lanyards from their attachment points of the forward firefloor at the mid position of the lower cowl. Refer to the enclosed GKN Aerospace Service Bulletin 1-71-23. (6) Remove bolts and washers and re-orientate position of the lanyards as required. Refer to the enclosed GN Aerospace Service Bulletin 1-71-23. 19 May 2011 S.B. 84-71-13 Page 6 of 18 VB ### Page 7 (OCR) SERVICE BULLETIN 84-71-13 (7) Apply sealant to bolts, washers and torque lanyard bolts as required. Refer to the enclosed GKN Aerospace Service Bulletin 1-71-23. (8) Install new spring clips CSP522-1 on the forward firefloor at the mid position of the lower cowl. Refer to the enclosed GN Aerospace Service Bulletin 1-71-23. (9) Secure lanyard cables in installed clips CSP522-1 as required. C. Close Out (1) Remove all tools and equipment from the work area. CAUTION: MAKE SURE NO RIVET STEMS, DRILLINGS, DEBRIS OR SEALANT IS LEFT WITHIN THE LOWER COWL. CAREFULLY INSPECT AND VACUUM OUT ALL POSSIBLE CONTAMINANTS TO PREVENT FOD. (2) Install the lower cowl on the aircraft. Refer to Aircraft Maintenance Manual PSM 1-84-2, TASK 71-10-16-400-801. (3) On incorporation of this ModSum make an entry that conforms to local regulatory requirements in the applicable logbooks). Enter component serial numbers if applicable. Enter this ModSum number only after complete and functional incorporation of all work defined in this service bulletin. 19 May 2011 S.B. 84-71-13 Page 7 of 18 VB ### Page 8 (OCR) SERVICE BULLETIN 84-71-13 GKN AEROSPACE SERVICE BULLETIN SUBJECT: Lower Cowl Expandable Pin Lanyard Reorientation and Clipping 1. PLANNING A. Effectivity Aircraft 4001, 4003 to 4364. B. Reason During routine maintenance activity, it has been found that a high-pressure fuel line can be chafed by contact with the lanyard from the Lower Cowl Expandable Pins (8SC0832). Therefore, this Service Bulletin is required to give a procedure to eliminate the possibility of fouling with and causing chafing damage to the high pressure fuel line. C. Description The design change is to introduce spring clips on the two forward and two mid expandable pin locations to positively retain the lanyards. The spring clips will be standard parts (CSP522) and will be installed on the Lower Cowl Assembly (87144300). It is also necessary to modify the attachment points of the lanyards at the two forward and two mid positions of the Lower Cowl. This procedure gives instructions for the repositioning of the lanyard attachment points, the installation of the spring clips and the orientation of the lanyards attachment to the Lower Cowl. D. Compliance To be accomplished in compliance time as instructed per Airworthiness Directive.. E. Classification Required Incorporation. F. Approval The technical content of the service bulletin has been approved under the authority of the Approval Organization No: DAO #93-Q-02. The technical content of this service bulletin has been reviewed and accepted by Bombardier Aerospace. G. Manpower To be determined by GNAe estimating. H. Material - Price and Availability Spring Clips (CSPS22-1) will be available from Bombardier. I. Tooling - Price and Availability • Normal Shop Tools. • Isopropyl Alcohol • DHMS S3.06 Typc 1, Class C-80 Sealant • Torque Wrench 0 to 30 Ibf in. (0 to 3,38 Nm). 1st March 2011 SB 1-71-23 Initial Issue Page 1 of 10 19 May 2011 S.B. 84-71-13 Page 8 of 18 VB ### Page 9 (OCR) SERVICE BULLETIN 84-71-13 A GKN AEROSPACE SERVICE BULLETIN J. Weight and Balance. Not affected. K. Electrical Load Data Not applicable L. Publications Affected • AMM (Aircraft Maintenance Manual), Part 2, PSM 1-84-2. • AIPC (Aircraft Illustrated Parts Catalog), PSM 1-84-4 • CMM (Component Maintenance Manual), PSM 1-84-6 M. References • E.I./TSE/11/001 Revision A. • Modsum 4V113715 Revision A • Bombardier Design Change Proposal (DCP) 43181. • GKN Change D400/0743. • Drawing 87144300 Revision 'AA' - Lower Cowl Assembly, Forward Nacelle. • Removal of the Lower Cowl, Aircraft Maintenance Manual PSM 1-84-2, Task 71-10-16-000-801. • Installation of the Lower Cowl, Aircraft Maintenance Manual PSM 1-84-2, Task 71-10-16-400-801. • Torque Standard Procedures, Aircraft Maintenance Manual PSM 1-84-2, Task 20-10-01-430-801. II MATERIAL INFORMATION A. Parts Supplied by Customer: Part Number Description Qty per Lower Cowl Qly per Aircraft B0207004M5-6 Rivet 2 4 M7885/8-5-04 Rivet 2 Ist March 2011 Initial Issue 19 May 2011 S.B. 84-71-13 VB ### Page 10 (OCR) SERVICE BULLETIN 84-71-13 GKN AEROSPACE SERVICE BULLETIN III ACCOMPLISHMENT INSTRUCTIONS WARNING: DO NOT BREATHE THE FUMES FROM ISO PROPYL ALCOHOL. IT IS POISONOUS AND VERY FLAMABLE. DO NOT GET IT ON YOUR SKIN OR IN YOUR EYES. USE ONLY IN AN AREA WITH CONTINUOUS AIRFLOW. TO KEEP ELECTRICAL CONTINUITY, GROUND ALL METAL CONTAINERS OF ISO PROPYL ALCOHOL. WEAR SAFETY CLOTHING, SPLASH GOGGLES AND A FACE SHIELD. NOTE: This procedure is applicable to the left and right hand Lower Cowl. A. Lower Cowl Expandable Pin Lanyard Reorientation and Clipping. 1. Obey all the relevant WARNINGS and CAUTIONS detailed in the Maintenance Manual PSM I-84-2. 2. Remove the aircraft electrical power. 3. Position the servicing platform at the forward nacelle. 4. Remove the lower cowl from the aircraft in accordance with Aircraft Maintenance Manual PSM 1-84-2, task 71-10-16-000-801. 5. Re-install each of the four expandable pins in the two forward and two mid lug holes to retain the pins in position for the procedure. 6. Locate the two forward lanyard positions on the lower cowl. Refer to Figure 1. 7. Removal of the two lanyards (3) from their attachment points at the forward position of the lower cowl. Refer to Figure 2, sheet 1. a. Remove the two bolts (1) (Part Number NAS6303U6) and two washers (2) (Part Number NAS 1587-A3C) from the anchor nuts that attach the lanyards (3) to the lower cowl. b. Using a clean lint free cloth moistened with Isopropyl Alcohol, clean the area where the bolts (1) and washers (2) were removed and allow to dry. c. Re-install the two bolts (1) and washers (2) removed in step 7.a. NOTE: Wet assemble the bolts (1) and washers (2) using DHMS S3.06 Type 1, Class C-80 Sealant. NOTE: Do not re-attach the lanyards (3) at these two positions. The lanyards will be re-located, see step 8. d. Torque tighten the bolts (1) 25 to 30 Ibf in. (2,82 to 3,38 Nm). Reference AMM PSM 1-84-2, Task 20-10-01-430-801, Torque Standard Procedures. 1st March 2011 SB 1-71-23 Initial Issue Page 3 of 10 19 May 2011 S.B. 84-71-13 Page 10 of 18 VB ### Page 11 (OCR) SERVICE BULLETIN 84-71-13 GKN AEROSPACE SERVICE BULLETIN e. Using a clean lint free cloth moistened with Isopropyl Alcohol, clean all used sealant from around the bolt and allow to dry. 8. Install the two lanyards (3) in their new attachment points at the forward position on the lower cowl. Refer to Figure 2, Sheet I. a. At the positions shown, remove the two bolts (4) (Part Number NAS6303U6) and two washers (5) (Part Number NAS1587-A3C) from the anchor nuts on the lower cowl. b. Using a clean lint free cloth moistened with Isopropyl Alcohol, clean the area where the bolts (4) and washers (S) were removed and allow to dry. c. Using the two bolts (4) and washers (5) removed in step 8.a., install the two lanyards (3) at their new attachment point locations. NOTE: Wet assemble the bolts (4) and washers (5) using DHMS S3.06 Type 1, Class C-80 Sealant. d. Torque tighten the bolts (4) 25 to 30 Ibf in. (2,82 to 3,38 Nm). Reference AMM PSM 1-84-2, Task 20-10-01-430-801, Torque Standard Procedures. e. Using a clean lint free cloth moistened with Isopropyl Alcohol, clean all used sealant from around the bolt and allow to dry. 9. Installation of the spring clips to retain the lanyards at the forward position. Refer to Figure 1 and Figure 2, Sheet 2. 10. Install the two spring clips (8) on the butt strap at the forward end of the lower cowl at the positions shown. Refer to Figure 2, Sheet 2 a. Using a drill, carefully remove two rivets (6), one from each side of the butt strap at the forward end of the lower cowl at the two positions shown. Discard b. Using a clean lint free cloth moistened with Isopropyl Alcohol, clean the area where the rivets (6) were removed and allow to dry. c. Using two new rivets (7) (Part Number B0207004M5-6), attach the two spring clips (8) (Part Number CSP522-1) in this position on each side of the butt strap at the forward end of the lower cowl. NOTE: Wet assemble with the rivets (7) using DHMS S3.06 Type 1, Class C-80 Sealant. d. Using a clean lint free cloth moistened with Isopropyl Alcohol, clean all used sealant from around the rivet area and allow to dry. 11. Locate the two mid lanyard positions on the lower cowl. Refer to Figure 1. 1st March 2011 SB 1-71-23 Initial Issue Page 4 of 10 19 May 2011 S.B. 84-71-13 Page 11 of 18 VB ### Page 12 (OCR) SERVICE BULLETIN 84-71-13 SERVICE BULLETIN 12. Removal of the two lanyards (11) from their attachment points on the forward firefloor at the mid position of the lower cowl. Refer to Figure 2, Sheet 3. a. Remove the two bolts (9) (Part Number NAS6303U3) and two washers (10) (Part Number NAS1587-A3C) from the anchor nuts that attach the lanyards (11) to the forward firefloor of the lower cowl. b. Using a clean lint free cloth moistened with Isopropyl Alcohol, clean the area where the bolts (9) and washers (10) were removed and allow to dry. c. Re-install the two bolts (9) and washers (10) removed in step 12.a. NOTE: Do not re-attach the lanyards (11) at these two positions. The lanyards will be re-located, see step 13. NOTE: Wet assemble the bolts (9) and washers (10) using DHMS $3.06 Type 1, Class C-80 Sealant. d. Torque tighten the bolts (9) 25 to 30 Ibf in. (2,82 to 3,38 Ni). Reference AMM PSM 1-84-2, Task 20-10-01-430-801, Torque Standard Procedures. e. Using a clean lint free cloth moistened with Isopropyl Alcohol, clean all used sealant from around the bolt and allow to dry. 13. Install the two lanyards (11) in their new attachment points on the forward firefloor at the mid position of the lower cowl. Refer to Figure 2, Sheet 3. a. At the positions shown, remove the two bolts (12) (Part Number NAS6303U3) and two washers (13) (Part Number NAS1587-A3C) from the anchor nuts on the lower cowl. b. Using a clean lint free cloth moistened with Isopropyl Alcohol, clean the area where the bolts (12) and washers (13) were removed and allow to dry. c. Using the two bolts (12) and washers (13) removed in step 13.a., install the two lanyards (11) at their new attachment point locations. NOTE: Wet assemble the bolts (12) and washers (13) using DHMS S3.06 Type 1, Class C-80 Sealant. d. Torque tighten the bolts (12) 25 to 30 Ibf in. (2,82 to 3,38 Nm). Reference AMM PSM 1-84-2, Task 20-10-01-430-801, Torque Standard Procedures. e. Using a clean lint free cloth moistened with Isopropyl Alcohol, clean all used sealant from around the bolt and allow to dry. 14. Installation of the spring clips to retain the lanyards at the mid position. Refer to Figure I and Figure 2, Sheet 3. 1st March 2011 SB 1-71-23 Initial Issue Page 5 of 10 19 May 2011 S.B. 84-71-13 Page 12 of 18 VB ### Page 13 (OCR) SERVICE BULLETIN 84-71-13 * GKN AEROSPACE SERVICE BULLETIN 15. Install the two spring clips (15) on the aft firefloor at the mid position of the lower cowl at the locations shown. Refer to Figure 2, Sheet 3. a. Using a drill, carefully remove two rivets (16), one from each side of the aft firefloor at the mid position of the lower cowl at the two positions shown. Discard the rivets. b. Using a clean lint free cloth moistened with Isopropyl Alcohol, clean the area where the rivets (16) were removed and allow to dry. c. Using two new rivets (14) (Part Number M7885/8-5-04), attach the two spring clips (15) (Part Number CSP522-1) in this position on each side of the aft firefloor at the mid position of the lower cowl. NOTE: Wet assemble with the rivets (14) using DHMS S3.06 Type 1, Class C-80 Sealant. d. Using a clean lint free cloth moistened with Isopropyl Alcohol, clean all used sealant from around the rivet area and allow to dry. B. Close up 1. Remove all tools, equipment and any unwanted parts or materials from the area. 2. Install the lower cowl on the aircraft in accordance with Aircraft Maintenance Manual PSM 1-84-2, task 71-10-16-400-801. 3. Remove the servicing platform from the nacelle. 4. Restore the aircraft electrical power. C. Record Service Bulletin Incorporation 1. On incorporation of this Service Bulletin, make an entry that conforms to the local regulatory requirements in the applicable logbook(s). Enter this Service Bulletin number only after complete and functional incorporation of all work defined in this service bulletin is embodied. Ist March 2011 SB 1-71-23 Initial Issue Page 6 of 10 19 May 2011 S.B. 84-71-13 Page 13 of 18 VB ### Page 14 (OCR) SERVICE BULLETIN 84-71-13 PEGKN AEROSPACE SERVICE BULLETIN D PRE MOD POST MOD Lower Cowl Expandable Pin Lanyard Location - Pre and Post Modification Figure 1 Ist March 2011 SB 1-71-23 Initial Issue Page 7 of 10 19 May 2011 S.B. 84-71-13 Page 14 of 18 VB ### Page 15 (OCR) SERVICE BULLETIN 84-71-13 GKN AEROSPACE SERVICE BULLETIN ..- 3 PRE MOD @ 3- POST MOD Lower Cowl Expandable Pin Lanyard Reorientation and Clipping Figure 2, Sheet 1 Ist March 2011 SB 1-71-23 Initial Issue Page 8 of 10 19 May 2011 S.B. 84-71-13 Page 15 of 18 VB ### Page 16 (OCR) SERVICE BULLETIN 84-71-13 VER GRN AEROSPACE SERVICE BULLETIN PRE MOD +11 - + + + + + POST MOD sh:21903 cam Lower Cowl Expandable Pin Lanyard Reorientation and Clipping Figure 2, Sheet 2 Ist March 2011 SB 1-71-23 Initial Issue Page 9 of 10 19 May 2011/ S.B. 84-71-13 Page 16 of 18 VB ### Page 17 (OCR) SERVICE BULLETIN 84-71-13 SERVICE BULLETIN PRE MOD POST MOD PRE MOD (н) POST MOD shy21a04.ogm Lower Cowl Expandable Pin Lanyard Reorientation and Clipping Figure 2, Sheet 3 1st March 2011 SB 1-71-23 Initial Issue Page 10 of 10 19 May 2011 S.B. 84-71-13 Page 17 of 18 VB ### Page 18 (OCR) SERVICE BULLETIN 84-71-13 This Page Intentionally Blank 19 May 2011 S.B. 84-71-13 Page 18 of 18 VB --- OpenAirDocs.org is an independent research project of [Contrail Labs](https://contraillabs.com/). 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