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Commercial Airplanes 737 Service Bulletin ALERT Number: 737-28A1273 Original Issue: December 23, 2014 Revision 1: March 14, 2017 ATA System: 2822 SUBJECT: FUEL - Engine Fuel Feed System - Wing and Center Tank Fuel Boost Pump Wire Bundle Replacement and Convoluted Liner Installation Export of this technology is controlled under the United States Export Administration Regulations (EAR) (15 CFR 300-774). An export license may be required before it is used for development, production or use by foreign persons from specific countries. The controller of this data has the individual responsibility to abide by all export laws.
9E991ECCN:
BOEING PROPRIETARY, CONFIDENTIAL AND/OR TRADE SECRET Copyright © 2014 Boeing.
Unpublished Work. All Rights Reserved.
Treatment of this document and its content is governed by contract with Boeing. Rights to use this document are licensed on a per aircraft basis and such rights may not be transferable. For more information, contact The Boeing Company.
Boeing, the Boeing signature, the Boeing symbol, 707, 717, 727, 737, 747, 757, 767, 777, 787, Dreamliner, BBJ, DC-8, DC-9, DC-10, KC-10, KC-46, KDC-10, MD-10, MD-11, MD-80, MD-88, MD-90, P-8, Poseidon and Boeing liveries are all trademarks owned by The Boeing Company; and no trademark license is granted in connection with this document unless provided in writing by Boeing.
Original Issue: December 23, 2014 737-28A1273Revision 1: March 14, 2017 1 of 234
2.0
Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details.
Original Issue: December 23, 2014 737-28A1273Revision 1: March 14, 2017 2 of 234 BOEING SERVICE BULLETIN 737-28A1273
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Table of Contents
Revision Transmittal Sheet7
S u m m a r y ..................................................... 1 1
1. PLANNING INFORMATION ........................................ 1 7 A . E f f e c t i v i t y ............................................... 1 7
1. Airplanes ............................................ 1 7 2 . S p a r e s A f f e c t e d ........................................ 2 9 B. Concurrent Requirements ...................................... 2 9 C. Reason ................................................ 3 0 D. Description .............................................. 3 1 E. Compliance .............................................. 3 2 F . A p p r o v a l ............................................... 3 2 G. Manpower .............................................. 3 3 H. Weight and Balance Changes .................................... 3 6 I. Electrical Load Data ......................................... 3 7 J . R e f e r e n c e s .............................................. 3 7
1. Existing Data: ......................................... 3 7
2. Data Supplied with this Service Bulletin: ........................... 3 8
3. Installation Drawings Used in the Preparation of this Service Bulletin: ........... 3 8 K. Publications Affected ........................................ 3 8 L. Interchangeability and Intermixability of Parts ........................... 3 9 M. Software Accomplishment Summary ................................ 3 9
2. MATERIAL INFORMATION ........................................ 4 1 A. Material - Price and Availability ................................... 4 1 B. Industry Support Information .................................... 4 3 C. Parts Necessary for Each Airplane ................................. 4 3 1 . K i t s / P a r t s ............................................ 4 3
2. Parts and Materials Supplied by the Operator ........................ 5 3
3. Parts Modified and Reidentified ................................ 5 3
4. Parts Removed and Not Replaced .............................. 5 3 D. Parts Necessary to Change Spares ................................. 5 4 E. Special Tooling - Price and Availability ............................... 5 4 F. Special Tooling Necessary to do this Service Bulletin ....................... 5 4
3. ACCOMPLISHMENT INSTRUCTIONS .................................. 5 5 A. GENERAL INFORMATION ..................................... 5 5 B. WORK INSTRUCTIONS ....................................... 5 7 FIGURE 1: STATION 520 LEFT GROUND BRACKET - INSTALLATION [Group 1] .......... 7 9 FIGURE 2: STATION 520 LEFT GROUND BRACKET - INSTALLATION [Group 2] .......... 8 2 FIGURE 3: STATION 520 RIGHT GROUND BRACKET - INSTALLATION [Group 1] .......... 8 5 FIGURE 4: STATION 520 RIGHT GROUND BRACKET - INSTALLATION [Group 2] .......... 8 8 FIGURE 5: LEFT WING - NO. 1 TANK AFT FUEL BOOST PUMP WIRE BUNDLE W512 AND LEFT CENTER TANK FUEL BOOST PUMP WIRE BUNDLE W514 - REMOVAL [Group 1-2] ....... 9 1 FIGURE 6: LEFT WING - NO. 1 TANK AFT FUEL BOOST PUMP WIRE BUNDLE W512 - REMOVAL [Group 1 - 2 ] ............................................... 9 4 FIGURE 7: LEFT WING - LEFT CENTER TANK FUEL BOOST PUMP WIRE BUNDLE W514 - REMOVAL [Group 1-2] ........................................... 9 5 Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details.
Original Issue: December 23, 2014 737-28A1273Revision 1: March 14, 2017 3 of 234 BOEING SERVICE BULLETIN 737-28A1273
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FIGURE 8: LEFT WING - NO. 1 TANK AFT FUEL TANK CONDUIT - REPLACEMENT [Group 1] . . . 96 FIGURE 9: LEFT WING - NO. 1 TANK AFT FUEL TANK CONDUIT - REPLACEMENT [Group 2] . . . 99 FIGURE 10: LEFT WING - LEFT CENTER TANK FUEL TANK CONDUIT - REPLACEMENT [Group 1] . 102 FIGURE 11: LEFT WING - LEFT CENTER TANK FUEL TANK CONDUIT - REPLACEMENT [Group 2] . 105 FIGURE 12: LEFT WING WIRE BUNDLE W512 AND WIRE BUNDLE W514 - ROUTING [Group 1-2] . 108 FIGURE 13: NO. 1 TANK AFT FUEL BOOST PUMP WIRE BUNDLE W512 - REMOVAL OR STOWAGE [Group 1-2] .......................................... 1 1 1 FIGURE 14: LEFT CENTER TANK FUEL BOOST PUMP WIRE BUNDLE W514 - REMOVAL OR STOWAGE [Group 1-2] .......................................... 1 1 5 FIGURE 15: LEFT WING CONVOLUTED LINERS, WIRE BUNDLE W512, AND WIRE BUNDLE W514 - INSTALLATION [Group 1-2] ................................. 1 1 9 FIGURE 16: LEFT WING WIRE BUNDLE W512 AND WIRE BUNDLE W514 - ROUTING [Group 1-2] . 127 FIGURE 17: LEFT WING - NO. 1 TANK AFT FUEL BOOST PUMP - WIRING CHANGE [Group 1-2] . 132 FIGURE 18: LEFT WING - NO. 1 TANK AFT FUEL BOOST PUMP WIRE BUNDLE W512 - WIRING CHANGE [Group 1-2] .......................................... 1 3 6 FIGURE 19: LEFT WING - LEFT CENTER TANK FUEL BOOST PUMP - WIRING CHANGE [Group 1-2] ................................................. 1 4 2 FIGURE 20: LEFT WING - LEFT CENTER TANK FUEL BOOST PUMP WIRE BUNDLE W514 - WIRING CHANGE [Group 1-2] ..................................... 1 4 6 FIGURE 21: STATION 520 LEFT GROUND STUD ASSEMBLY - WIRE BUNDLE W512 AND WIRE BUNDLE W514 [Group 1] ........................................ 1 5 2 FIGURE 22: STATION 520 LEFT GROUND STUD ASSEMBLY - WIRE BUNDLE W512 AND WIRE BUNDLE W514 [Group 2] ........................................ 1 5 5 FIGURE 23: RIGHT WING - RIGHT CENTER TANK FUEL BOOST PUMP WIRE BUNDLE W516 AND NO.
2 TANK AFT FUEL BOOST PUMP WIRE BUNDLE W520 - REMOVAL [Group 1-2] . . . 158 FIGURE 24: RIGHT CENTER TANK FUEL BOOST PUMP WIRE BUNDLE W516 - REMOVAL [Group 1-2] ................................................. 1 6 1 FIGURE 25: NO. 2 TANK AFT FUEL BOOST PUMP WIRE BUNDLE W520 - REMOVAL [Group 1-2] . 162 FIGURE 26: RIGHT WING - RIGHT CENTER TANK FUEL TANK CONDUIT - REPLACEMENT [Group 1] ................................................. 1 6 3 FIGURE 27: RIGHT WING - RIGHT CENTER TANK FUEL TANK CONDUIT - REPLACEMENT [Group 2] ................................................. 1 6 6 FIGURE 28: RIGHT WING - NO. 2 TANK AFT FUEL TANK CONDUIT - REPLACEMENT [Group 1] . 169 FIGURE 29: RIGHT WING - NO. 2 TANK AFT FUEL TANK CONDUIT - REPLACEMENT [Group 2] . 172 FIGURE 30: RIGHT WING WIRE BUNDLE W516 AND WIRE BUNDLE W520 - ROUTING [Group 1] . 175 FIGURE 31: RIGHT WING WIRE BUNDLE W516 AND WIRE BUNDLE W520 - ROUTING [Group 2] . 178 FIGURE 32: RIGHT CENTER TANK FUEL BOOST PUMP WIRE BUNDLE W516 - REMOVAL OR STOWAGE [Group 1-2] .......................................... 1 8 1 FIGURE 33: NO. 2 TANK AFT FUEL BOOST PUMP WIRE BUNDLE W520 - REMOVAL OR STOWAGE [Group 1-2] .......................................... 1 8 5 FIGURE 34: RIGHT WING CONVOLUTED LINERS, WIRE BUNDLE W516, AND WIRE BUNDLE W520 - INSTALLATION [Group 1-2] ................................. 1 8 9 FIGURE 35: RIGHT WING WIRE BUNDLE W516 AND WIRE BUNDLE W520 - ROUTING [Group 1] . 197 FIGURE 36: RIGHT WING WIRE BUNDLE W516 AND WIRE BUNDLE W520 - ROUTING [Group 2] . 202 FIGURE 37: RIGHT WING - RIGHT CENTER TANK FUEL BOOST PUMP - WIRING CHANGE [Group 1-2] ................................................. 2 0 7 FIGURE 38: RIGHT WING - RIGHT CENTER TANK FUEL BOOST PUMP WIRE BUNDLE W516 - WIRING CHANGE [Group 1-2] ..................................... 2 1 1 Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details.
Original Issue: December 23, 2014 737-28A1273Revision 1: March 14, 2017 4 of 234 BOEING SERVICE BULLETIN 737-28A1273
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FIGURE 39: RIGHT WING - NO. 2 TANK AFT FUEL BOOST PUMP - WIRING CHANGE [Group 1-2] . 217 FIGURE 40: RIGHT WING - NO. 2 TANK AFT FUEL BOOST PUMP WIRE BUNDLE W520 - WIRING CHANGE [Group 1-2] ..................................... 2 2 1 FIGURE 41: STATION 520 RIGHT GROUND STUD ASSEMBLY - WIRE BUNDLE W516 AND WIRE BUNDLE W520 [Group 1] ........................................ 2 2 7 FIGURE 42: STATION 520 RIGHT GROUND STUD ASSEMBLY - WIRE BUNDLE W516 AND WIRE BUNDLE W520 [Group 2] ........................................ 2 3 0 APPENDIX A: SHIELDED WIRE INSTALLATION - GENERAL SCOPE OF WORK [Group 1-2] ..... 2 3 3 APPENDIX B: PART DEMAND INTENT ................................... 2 3 4 Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details.
Original Issue: December 23, 2014 737-28A1273Revision 1: March 14, 2017 5 of 234 BOEING SERVICE BULLETIN 737-28A1273
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Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details.
Original Issue: December 23, 2014 737-28A1273Revision 1: March 14, 2017 6 of 234 BOEING SERVICE BULLETIN 737-28A1273
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Commercial Airplanes 737 Service Bulletin ALERT Revision Transmittal SheetNumber: 737-28A1273Original Issue: December 23, 2014 Revision 1: March 14, 2017 ATA System: 2822 SUBJECT: FUEL - Engine Fuel Feed System - Wing and Center Tank Fuel Boost Pump Wire Bundle Replacement and Convoluted Liner Installation This revision includes all pages of the service bulletin.
COMPLIANCE INFORMATION RELATED TO THIS REVISION Effects of this Revision on airplanes on which the Original Issue was previously done:
None.
REASON FOR REVISION This revision is sent to incorporate changes found during two validations of this service bulletin. This revision also deletes two figures that remove the fuel boost pumps, because removal of the fuel boost pumps is not necessary. Subsequent Figures are renumbered accordingly.
These sections were changed:
1. Summary, Concurrent Requirements - Added statement.
2. Summary, Background - Added validation statement. Added Limit of Validity (LOV) statement for Group
3.
3. Summary, Action - Revised to match Accomplishment Instructions. Added LOV statement for Group
3.
4. Summary, Compliance and Paragraph 1.E., Compliance - Revised statement. Added LOV statement for Group 3.
5. Paragraph 1.B., Concurrent Requirements - Added table.
6. Paragraph 1.C., Reason - Added revision information. Added LOV statement for Group 3.
7. Paragraph 1.D., Description - Revised to match Accomplishment Instructions. Added LOV statement for Group 3.
8. Paragraph 1.F., Approval - Revised statement.
9. Paragraph 1.G., Manpower - Revised estimate. Added LOV statement for Group 3.
Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details.
Original Issue: December 23, 2014 737-28A1273Revision 1: March 14, 2017 7 of 234
10. Paragraph 1.H., Weight and Balance Changes - Revised data.
11. Paragraph 1.J., References - Updated the reference list.
12. Paragraph 1.K., Publications Affected - Revised data.
13. Paragraph 2.A., Material - Price - and Availability - Revised data. Added LOV statement for Group 3.
14. Paragraph 2.C., Parts Necessary for Each Airplane - Revised part numbers and added footnotes.
15. Paragraph 2.C.2., Parts and Materials Supplied by the Operator - Updated table.
16. Paragraph 3.A., General Information - Added caution and updated notes.
17. Paragraph 3.B., Work Instructions, Group 1 and Group 2 - Deleted step to remove the fuel boost pumps, added and revised access information, revised Figure numbers. Added LOV statement for Group 3.
18. FIGURE 1 to FIGURE 4 - Revised footnote (a).
19. FIGURE 5 and FIGURE 6 in the Original Issue were deleted. Subsequent Figures were renumbered accordingly.
20. FIGURE 8 to FIGURE 11 and FIGURE 26 to FIGURE 29 - Revised quantities.
21. FIGURE 15, FIGURE 21, FIGURE 22, FIGURE 34, FIGURE 41 and FIGURE 42 - Changed part numbers.
22. FIGURE 16, FIGURE 35 and FIGURE 36 - Revised quantities and footnote (a).
23. FIGURE 17, FIGURE 19, FIGURE 37 and FIGURE 39 - Revised Title, Sheet 1, Sheet 2 and step table.
24. FIGURE 18, FIGURE 20, FIGURE 38 and FIGURE 40 - Revised wire kit numbers and footnotes.
As a part of a service bulletin validation program, this change was completed on airplane PW595 by Service Bulletin 737-28A1273 Original Issue before the release of Revision 1 of this service bulletin. The change completed on airplane PW595 by Service Bulletin 737-28A1273 Original Issue is equivalent to the release of Revision 1 of this service bulletin. Airplane PW595 has the configuration of a Group 2 airplane.
As a part of a service bulletin validation program, this change was completed on airplane PS973 by Service Bulletin 737-28A1273 Revision 1, Validation Copy 1 before the release of Revision 1 of this service bulletin. The change completed on airplane PS973 by Service Bulletin 737-28A1273 Revision 1, Validation Copy 1 is equivalent to the release of Revision 1 of this service bulletin. Airplane PS973 has the configuration of a Group 2 airplane.
Vertical lines are put on the left edge of each page, except in Paragraph 1.A., Effectivity and format changes, to show the location of all content changes.
Pages with no vertical lines have no changes.
REVISION HISTORY December 23, 2014Original Issue:
Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details.
Original Issue: December 23, 2014 737-28A1273Revision 1: March 14, 2017 8 of 234 BOEING SERVICE BULLETIN 737-28A1273
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March 14, 2017Revision 1:
Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details.
Original Issue: December 23, 2014 737-28A1273Revision 1: March 14, 2017 9 of 234 BOEING SERVICE BULLETIN 737-28A1273
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Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details.
Original Issue: December 23, 2014 737-28A1273Revision 1: March 14, 2017 10 of 234 BOEING SERVICE BULLETIN 737-28A1273
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Commercial Airplanes 737 Service Bulletin ALERT SummaryNumber: 737-28A1273Original Issue: December 23, 2014 Revision 1: March 14, 2017 ATA System: 2822 SUBJECT: FUEL - Engine Fuel Feed System - Wing and Center Tank Fuel Boost Pump Wire Bundle Replacement and Convoluted Liner Installation
THIS DOCUMENT IS SENT TO THE OPERATORS OF RECORD OF THE AIRPLANES SHOWN IN PARAGRAPH 1.A., EFFECTIVITY. IF AN AIRPLANE HAS BEEN LEASED OR SOLD, SEND THIS DOCUMENT TO THE NEW OPERATOR. IF APPLICABLE SPARES HAVE BEEN SOLD, SEND THIS DOCUMENT TO THE NEW OWNER.
CONCURRENT REQUIREMENTS Refer to Paragraph 1.B., Concurrent Requirements.
BACKGROUND This service bulletin installs new fuel boost pump wire bundles in the wing and center fuel tanks. New shielded wire bundles in convoluted liners are installed in the fuel tank conduits with wire shield grounding at the fuel boost pump housing and pressure seal. Boeing has issued this service bulletin so that the wiring and sleeve no longer need to be removed and inspected every 15,000 hours in accordance with Boeing Service Bulletin 737-28A1263 and the subject of Federal Aviation Administration (FAA) Airworthiness Directive AD 2007-24-02.
If this service bulletin is not done, wire bundle damage can occur, which could cause arcing and a possible burn through condition which could result in a potential source of ignition in a fuel tank and consequent fire or explosion.
Boeing Service Bulletin 737-28A1263 was issued because damage was found during the repetitive inspection in accordance with Boeing Service Bulletin 737-28A1120 and mandated by Federal Aviation Administration (FAA) Airworthiness Directive AD 99-21-15. The damage was found to the sleeve, jacket, and insulation on the electrical wire. The sleeve was worn through at three locations. At two of the locations the damage was also through the jacket of the electrical wire and exposed the insulation on the electrical wire inside the jacket. The wear did not expose the conductor of the electrical wire. The damage was found approximately 21,000 hours after installation of the sleeve. The 21,000 hours is less than the 30,000 repeat inspection interval hours specified in Federal Aviation Administration (FAA) Airworthiness Directive AD 99-21-15.
Boeing has issued this service bulletin as a final solution to this condition and to replace Boeing Service Bulletin 737-28A1263. Accomplishment of this service bulletin installs new shielded wire bundles in convoluted liners in the wing and center fuel tank conduits. The convoluted liner will decrease the chance of wire bundle damage.
The new shielded wiring will provide a ground path for the Ground Fault Interrupter (GFI) to trip if there is shorting in the wiring. This installation will help prevent a potential ignition sources that can cause consequent fire or explosion. The GFI is installed by Boeing Service Bulletin 737-28A1212.
Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details.
Original Issue: December 23, 2014 737-28A1273Revision 1: March 14, 2017 11 of 234
Group 1:
This change affects Airworthiness Limitations document D6-38278-CMR. The new Airworthiness Limitation (AWL) that follows is added: 28-AWL-26 (for 737-100, -200, -200C airplanes). This AWL provides maintenance instructions and replaces the requirements of Airworthiness Limitation 28-AWL-18.
Group 2:
This change affects Airworthiness Limitations document D6-38278-CMR. The new Airworthiness Limitation (AWL) that follows is added: 28-AWL-25 (for 737-300, -400, -500 airplanes). This AWL provides maintenance instructions and replaces the requirements of Airworthiness Limitation 28-AWL-18.
Group 3:
Boeing endorses the FAA rules related to Limit of Validity (LOV) and recommends immediate and permanent removal from service of any airplanes upon reaching the LOV, whether or not it is operated under FAA jurisdiction.
As such, Boeing no longer provides maintenance instructions for airplanes that have accumulated flight cycles beyond the LOV. Airplanes in Group 3 (line numbers 1-291) have accumulated flight cycles beyond the LOV of the maintenance program. 14 CFR 121.1115 and 129.115 prohibit operation of an airplane beyond its LOV.
As a part of a service bulletin validation program, this change was completed on airplane PW595 by Service Bulletin 737-28A1273 Original Issue before the release of Revision 1 of this service bulletin. The change completed on airplane PW595 by Service Bulletin 737-28A1273 Original Issue is equivalent to the release of Revision 1 of this service bulletin. Airplane PW595 has the configuration of a Group 2 airplane.
As a part of a service bulletin validation program, this change was completed on airplane PS973 by Service Bulletin 737-28A1273 Revision 1, Validation Copy 1 before the release of Revision 1 of this service bulletin. The change completed on airplane PS973 by Service Bulletin 737-28A1273 Revision 1, Validation Copy 1 is equivalent to the release of Revision 1 of this service bulletin. Airplane PS973 has the configuration of a Group 2 airplane.
Accomplishment of the work in accordance with this service bulletin gives terminating action to the repeat inspections in accordance with service bulletin 737-28A1263.
Boeing Service Related Problem (SRP) 737-SRP-28-0113 is related to this service bulletin.
This table is provided to operators for planning purposes only. Refer to the applicable sections for more information.
ReferenceAffectedPlanning Data Paragraph 1.A.2., Spares AffectedNoSpares Affected Paragraph 1.E., Compliance and Paragraph
1.F., Approval YesAD Related Paragraph 1.H., Weight and Balance ChangesYesWeight and Balance Change Paragraph 1.I., Electrical Load DataNoElectrical Load Changed Paragraph 1.K., Publications AffectedYesPublications Affected Paragraph 1.K., Publications AffectedNoAirplane Flight Operations Affected (Flight Crew Operations Manual and/or FAA Approved Airplane Flight Manual) Paragraph 2.C.1., Kits/PartsYesKits/Parts Required Paragraph 2.C.2., Parts and Materials Supplied by the Operator YesOperator Supplied Parts/Material Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details.
Original Issue: December 23, 2014 737-28A1273Revision 1: March 14, 2017 12 of 234 BOEING SERVICE BULLETIN 737-28A1273