# Boeing Alert Service Bulletin 777-53A0075: Revision 1

- Rights: © The Boeing Company. Filed by the FAA in regulations.gov docket FAA-2015-1428; AD 2016-09-01 incorporates this document by reference. Not covered by OpenAirDocs’ CC0 dedication.
- Document: [Boeing Alert Service Bulletin 777-53A0075](https://openairdocs.org/service-documents/boeing/777-53a0075.md)
- Title as filed: U.S. DOT/FAA - Boeing SB-777-53A0075-01
- Pages: 248
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## Text

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### Page 1

Commercial 
Airplanes
777
Service Bulletin
ALERT
Number: 777-53A0075
Original Issue: January 14, 2015
Revision 1: December 14, 2015
ATA System: 5380
SUBJECT: FUSELAGE - Section 48 - Station 2370 Pivot Bulkhead Forward Outer Chord -
Inspection and Repair
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 © 2015 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Unpublished Work.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: January 14, 2015
777-53A0075Revision 1: December 14, 2015
1 of 248
2.0

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Table of Contents
Revision Transmittal Sheet ............................................ 5
S u m m a r y  ...................................................... 9
1. PLANNING INFORMATION ........................................ 1 5
A . E f f e c t i v i t y  ............................................... 1 5
1. Airplanes ............................................ 1 5
2 . S p a r e s  A f f e c t e d  ........................................ 1 7
B. Concurrent Requirements ...................................... 1 7
C. Reason ................................................ 1 7
D. Description .............................................. 1 8
E. Compliance .............................................. 1 9
F . A p p r o v a l  ............................................... 2 2
G. Manpower .............................................. 2 3
H. Weight and Balance Changes .................................... 2 6
I. Electrical Load Data ......................................... 2 6
J . R e f e r e n c e s  .............................................. 2 6
1. Existing Data: ......................................... 2 6
2. Data Supplied with this Service Bulletin: ........................... 2 6
3. Installation Drawings Used in the Preparation of this Service Bulletin: ........... 2 7
K. Publications Affected ........................................ 2 7
L. Interchangeability and Intermixability of Parts ........................... 2 7
M. Software Accomplishment Summary ................................ 2 7
2. MATERIAL INFORMATION ........................................ 2 9
A. Material - Price and Availability ................................... 2 9
B. Industry Support Information .................................... 3 0
C. Parts Necessary for Each Airplane ................................. 3 0
1 . K i t s / P a r t s  ............................................ 3 0
2. Parts and Materials Supplied by the Operator ........................ 3 4
3. Parts Modified and Reidentified ................................ 3 5
4. Parts Removed and Not Replaced .............................. 3 5
D. Parts Necessary to Change Spares ................................. 3 5
E. Special Tooling - Price and Availability ............................... 3 5
F. Special Tooling Necessary to do this Service Bulletin ....................... 3 5
3. ACCOMPLISHMENT INSTRUCTIONS .................................. 3 7
A. GENERAL INFORMATION ..................................... 3 7
B. WORK INSTRUCTIONS ....................................... 3 9
FIGURE 1: LEFT SIDE - STA 2370 SKIN PANEL REMOVAL ...................... 4 3
FIGURE 2: RIGHT SIDE - STA 2370 SKIN PANEL REMOVAL ..................... 4 7
FIGURE 3: LEFT SIDE - STA 2370 PIVOT BULKHEAD FORWARD OUTER CHORD - DET AND HFEC
INSPECTION .......................................... 5 1
FIGURE 4: RIGHT SIDE - STA 2370 PIVOT BULKHEAD FORWARD OUTER CHORD - DET AND HFEC
INSPECTION .......................................... 5 5
FIGURE 5: LEFT SIDE - STA 2370 SKIN PANEL INSTALLATION ................... 5 9
FIGURE 6: RIGHT SIDE - STA 2370 SKIN PANEL INSTALLATION ................... 6 4
FIGURE 7: LEFT SIDE - STA 2370 PIVOT BULKHEAD FORWARD OUTER CHORD - PART REMOVAL
[Group 1] ............................................ 6 9
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FIGURE 8: RIGHT SIDE - STA 2370 PIVOT BULKHEAD FORWARD OUTER CHORD - PART REMOVAL
[Group 1] ............................................ 7 9
FIGURE 9: LEFT SIDE - STA 2370 PIVOT BULKHEAD FORWARD OUTER CHORD - PART REMOVAL
[Group 2] ............................................ 8 9
FIGURE 10: RIGHT SIDE - STA 2370 PIVOT BULKHEAD FORWARD OUTER CHORD - PART REMOVAL
[Group 2] ............................................ 9 9
FIGURE 11: LEFT SIDE - STA 2370 PIVOT BULKHEAD FORWARD OUTER CHORD AND ADJACENT
STRUCTURE - HFEC AND DET INSPECTION ....................... 1 0 9
FIGURE 12: RIGHT SIDE - STA 2370 PIVOT BULKHEAD FORWARD OUTER CHORD AND ADJACENT
STRUCTURE - HFEC AND DET INSPECTION ....................... 1 1 4
FIGURE 13: LEFT SIDE - STA 2370 - SPLICE ANGLE - MODIFICATION [Group 1] .......... 1 1 9
FIGURE 14: RIGHT SIDE - STA 2370 - SPLICE ANGLE - MODIFICATION [Group 1] ......... 1 2 2
FIGURE 15: LEFT SIDE - STA 2370 PIVOT BULKHEAD FORWARD CHORD - REPAIR [Group 1] . 125
FIGURE 16: RIGHT SIDE - STA 2370 PIVOT BULKHEAD FORWARD CHORD - REPAIR [Group 1] . 147
FIGURE 17: LEFT SIDE - STA 2370 PIVOT BULKHEAD FORWARD CHORD - REPAIR [Group 2] . 167
FIGURE 18: RIGHT SIDE - STA 2370 PIVOT BULKHEAD FORWARD CHORD - REPAIR [Group 2] . 187
FIGURE 19: LEFT SIDE - STA 2370 PIVOT BULKHEAD FORWARD CHORD - POST-REPAIR DET AND
HFEC INSPECTION ..................................... 2 0 7
FIGURE 20: RIGHT SIDE - STA 2370 PIVOT BULKHEAD FORWARD CHORD - POST-REPAIR DET AND
HFEC INSPECTION ..................................... 2 1 0
FIGURE 21: LEFT SIDE - STA 2370 PIVOT BULKHEAD FORWARD CHORD POST-REPAIR INSPECTION
- SKIN PANEL INSTALLATION ............................... 2 1 3
FIGURE 22: RIGHT SIDE - STA 2370 PIVOT BULKHEAD FORWARD CHORD POST-REPAIR INSPECTION
- SKIN PANEL INSTALLATION ............................... 2 1 8
FIGURE 23: LEFT SIDE - STA 2370 PIVOT BULKHEAD FORWARD CHORD POST-REPAIR - SKIN PANEL
INSTALLATION ........................................ 2 2 3
FIGURE 24: RIGHT SIDE - STA 2370 PIVOT BULKHEAD FORWARD CHORD POST-REPAIR - SKIN PANEL
INSTALLATION ........................................ 2 2 9
FIGURE 25: LEFT SIDE - STA 2370 SKIN PANEL REMOVAL ...................... 2 3 5
FIGURE 26: RIGHT SIDE - STA 2370 SKIN PANEL REMOVAL ..................... 2 3 9
APPENDIX A: LOGIC DIAGRAM FOR PARAGRAPH 1.E., COMPLIANCE: TABLE 1: DETAILED AND HFEC
INSPECTION OF THE STATION 2370 PIVOT BULKHEAD FORWARD CHORD .... 2 4 3
APPENDIX B: L OGIC DIAGRAM FOR PARAGRAPH 1.E., COMPLIANCE: TABLE 2: POST-REPAIR DETAILED
AND HFEC INSPECTION OF THE STATION 2370 PIVOT BULKHEAD FORWARD CHORD
................................................. 2 4 6
APPENDIX C: BOEING PART DEMAND INTENT .............................. 2 4 8
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ALERTALERT

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Commercial 
Airplanes
777
Service Bulletin
ALERT
Revision Transmittal SheetNumber: 777-53A0075Original Issue: January 14, 2015
Revision 1: December 14, 2015
ATA System: 5380
SUBJECT: FUSELAGE - Section 48 - Station 2370 Pivot Bulkhead Forward Outer Chord -
Inspection and Repair
This revision includes all pages of the service bulletin.
COMPLIANCE INFORMATION RELATED TO THIS REVISION
Federal Aviation Administration (FAA) Notice of Proposed Rule Making NPRM 2015-NM-026-AD, is related to
this service bulletin.
Effects of this Revision on airplanes on which Original Issue was previously done:
None.
REASON FOR REVISION
This revision is sent to make changes identified during the validation of the Original Issue of this service bulletin
and to clarify or correct issues identified by operators since the Original Issue.
As a part of a service bulletin validation program, this inspection was completed on airplane WA174 by Service
Bulletin 777-53A0075 Original Issue before the release of Revision 1 of this service bulletin. The inspection
completed on airplane WA174 by Service Bulletin 777-53A0075 Original Issue is equivalent to the release of
Revision 1 of this service bulletin. Airplane WA174 has the configuration of a Group 2 airplane.
These sections were changed:
1. In Summary, Background, revised the description of the unsafe condition, revised the number of operator
reports, added a service history table, added a description of the completed service bulletin validation.
2. In Summary, Action, revised the paragraph.
3. In Summary, Compliance, added FAA Notice of Proposed Rule Making (NPRM) reference.
4. In Summary, Manpower, added a reference to Paragraph 1.G., Manpower.
5. In Summary, Material Information, added "Operator Supplied Parts/Materials".
6. In Summary, revised the summary illustration.
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7. In Paragraph 1.C., Reason, revised the description of the unsafe condition, revised the number of
operator reports, added a service history table, added paragraphs to give a description of the completed
service bulletin validation and to give the reason for this revision.
8. In Paragraph 1.D., Description, revised the paragraph, added paragraph to give the effects of this
revision on airplanes on which Original Issue was previously done.
9. In Paragraph 1.E., Compliance, added NPRM reference, revised the paragraph above Table 1, revised
Table 1 and Table 2.
10. In Paragraph 1.G., Manpower, revised the tables.
11. In Paragraph 1.H., Weight and Balance Changes, revised the table to give weight and balance changes.
12. In Paragraph 1.J., References, revised the reference list.
13. In Paragraph 2.A., Material - Price and Availability, revised top kit dates and quantities, added Reorder
Lead Time (ROLT) and revised price information.
14. In Paragraph 2.C.1., Kits/Parts, revised the top kit parts lists.
15. In Paragraph 2.C.2., Parts and Materials Supplied by the Operator, deleted the duplicate paragraph
above the table.
16. In Paragraph 2.C.3., Parts Modified and Reidentified, added table for Group 1 airplanes, added paragraph
for Group 2 airplanes.
17. In Paragraph 3.A., General Information, deleted notes that are not applicable, revised note 17. and
note 18.
18. In Paragraph 3.B., Work Instructions, revised the work instructions.
19. In Figure 5 and Figure 6, revised the illustrations and the fastener code table.
20. In Figure 7, Figure 8, Figure 9 and Figure 10, revised the illustrations and the step table.
21. In Figure 11, Figure 12, Figure 13 and Figure 14, revised the illustrations.
22. In Figure 15, Figure 16, Figure 17, Figure 18, Figure 21, Figure 22, Figure 23 and Figure 24, revised
the illustrations, the step table and the fastener code table.
23. Added Figure 25 and Figure 26 to give instructions for skin panel removal after the small crack repair
was installed.
24. In Appendix A, revised the table and the flag note, revised the logic diagram.
25. In Appendix B, revised the table and the flag note.
26. In Appendix C, revised Part Demand Intent.
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.
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Pages with no vertical lines have no changes.
REVISION HISTORY
January 14, 2015Original Issue:
December 14, 2015Revision 1:
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Commercial 
Airplanes
777
Service Bulletin
ALERT
SummaryNumber: 777-53A0075Original Issue: January 14, 2015
Revision 1: December 14, 2015
ATA System: 5380
SUBJECT: FUSELAGE - Section 48 - Station 2370 Pivot Bulkhead Forward Outer Chord -
Inspection and Repair
THIS BULLETIN 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 SERVICE BULLETIN TO
THE NEW OPERATOR. IF APPLICABLE SPARES HAVE BEEN SOLD, SEND THIS SERVICE BULLETIN TO
THE NEW OWNER.
CONCURRENT REQUIREMENTS
None.
BACKGROUND
This service bulletin is sent to give instructions for inspections of the left and right side forward outer chords of
the Body Station (STA) 2370 pivot bulkhead for cracks. Cracks in the STA 2370 pivot bulkhead forward outer
chords that are not found and repaired can become large and result in a severed forward outer chord. Since
the horizontal stabilizer is attached to the STA 2370 bulkhead at two pivot locations, this damage could cause
the loss of horizontal stabilizer control, resulting in loss of controllability of the airplane.
Two operators have reported finding cracks in the outer flanges of the left and right side forward outer chords
of the STA 2370 pivot bulkhead on a total of eleven airplanes. The cracks were fatigue cracks caused by a
stress concentration which is generated at the transition radius of the forward outer flange of the chord prior to
the chord splice at the upper longeron.
Accomplishment of the inspections in this service bulletin will help ensure that STA 2370 pivot bulkhead forward
outer chord cracks are found and repaired before they can become large and result in damage that could result
in the loss of horizontal stabilizer control.
Boeing Service Bulletin (SB) 777-53-0076 gives instructions for a modification that is terminating action to the
repeat inspections given in this service bulletin.
The table below shows the crack findings and related service data that have been reported to Boeing.
Service History
Crack Length (Inches)Crack LocationFlight HoursFlight CyclesModel
1.4 and 3.3Left Side39,14231,384777-200
2.93Right Side
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Service History
Crack Length (Inches)Crack LocationFlight HoursFlight CyclesModel
2.3Left Side39,79731,504777-200
2.2Right Side
2.5Left Side38,75832,181777-200
2.3Right Side
2.5Left Side37,18229,383777-200
2.5Right Side
2.2Left Side34,29124,653777-300
2.2Right Side
2.25Left Side40,07435,011777-200
2.2Right Side
2.5Left Side33,56824,251777-300
2.03Right Side
2.35Left Side38,45530,462777-200
2.2Right Side
2.2Left Side39,16630,826777-200
2.4Right Side
2.5Left Side40,58833,809777-200
2.4Right Side
1.2Left Side63,94017,530777-300
1.65Right Side
Boeing Fleet Team Digest (FTD) 777 FTD 53-13001 is related to this service bulletin.
Boeing Service Related Problem (SRP) 777-SRP-53-0455 is related to this service bulletin.
As a part of a service bulletin validation program, this inspection was completed on airplane WA174 by Service
Bulletin 777-53A0075 Original Issue before the release of Revision 1 of this service bulletin. The inspection
completed on airplane WA174 by Service Bulletin 777-53A0075 Original Issue is equivalent to the release of
Revision 1 of this service bulletin. Airplane WA174 has the configuration of a Group 2 airplane.
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
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ReferenceAffectedPlanning Data
Paragraph 1.H., Weight and Balance ChangesYes (a)Weight 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 Air-
plane 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
Paragraph 2.F., Special Tooling Necessary to
do this Service Bulletin
NoSpecial Tooling Required
(a) Only if the repair was done.
ACTION (PRR 62777-97S)
Do a Detailed and HFEC inspection of the Station 2370 pivot bulkhead forward chord in accordance with PART
1, for any crack.
If any crack is found, and no crack found is greater than 0.160 inch, do one of the following options on the
affected side of the airplane:
1. Do the terminating action in accordance with SB 777-53-0076.
2. Do the repair of the Station 2370 pivot bulkhead forward chord in accordance with PART 2 and the
post-repair Detailed and HFEC inspection in accordance with PART 3.
If any crack found is greater than 0.160 inch, do the terminating action in accordance with SB 777-53-0076.
If no crack is found, repeat PART 1, or do the terminating action in accordance with SB 777-53-0076.
EFFECTIVITY
777-200/-300 Airplanes. Refer to Paragraph 1.A.1., Airplanes, for the list of affected airplanes.
COMPLIANCE
Federal Aviation Administration (FAA) Notice of Proposed Rule Making NPRM 2015-NM-026-AD, is related to
this service bulletin.
Refer to Paragraph 1.E., Compliance.
INDUSTRY SUPPORT INFORMATION
Boeing warranty remedies are available for airplanes in warranty as of November 20, 2013. Please refer to
Paragraph 2.B., Industry Support Information. The warranty remedies will expire eight years from the original
issue date of this service bulletin.
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MANPOWER
Elapsed HoursTotal Task HoursAirplanes
10.5014.50All Airplanes - Inspection
24.0544.85Group 1 Airplanes - Small Crack Repair
- One Side of the airplane
22.3043.10Group 2 Airplanes - Small Crack Repair
- One Side of the airplane
8.5010.50All Airplanes - Post-Repair Inspection
Refer to Paragraph 1.G., Manpower.
MATERIAL INFORMATION
Boeing Supplied Kits/Parts.
Operator Supplied Parts/Materials.
Refer to Paragraph 2.A., Material - Price and Availability.
Operators are encouraged to complete the survey provided in APPENDIX C of this service bulletin to help Boeing
predict the quantity and timing of the Boeing Supplied Kits/Parts.
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### Page 13 (OCR)

BOEING SERVICE BULLETIN 777-53A0075
ALERT  ALERT
LEFT AND RIGHT SIDE:
DO A DETAILED AND HFEC INSPECTION OF THE
STATION 2370 PIVOT BULKHEAD FORWARD CHORD
STA  IN ACCORDANCE WITH PART 1, FOR ANY CRACK
2370  F ANY CRACK IS FOUND. AND NO CRACK FOUND IS
GREATER THAN 0.160 INCH, DO ONE OF THE
FOLLOWING OPTIONS ON THE AFFECTED SIDE OF
THE AIRPLANE:
1. DO THE TERMINATING ACTION IN
ACCORDANCE WITH SB 777-53-0076.
2. DO THE REPAIR OF THE STATION 2370 PIVOT
BULKHEAD FORWARD CHORD IN ACCORDANCE
WITH PART 2, AND THE POST-REPAIR DETAILED
AND HFEC INSPECTION IN ACCORDANCE WITH
PART 3
IF ANY CRACK FOUND IS GREATER THAN 0.160
INCH, DO THE TERMINATING ACTION IN
ACCORDANCE WITH SB 777-53-0076
IF NO CRACK IS FOUND, REPEAT PART 1, OR DO
THE TERMINATING ACTION IN ACCORDANCE WITH
SB 777-53-0076.
2357294
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### Page 14

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Commercial 
Airplanes
777
Service Bulletin
ALERT
Number: 777-53A0075
Original Issue: January 14, 2015
Revision 1: December 14, 2015
ATA System: 5380
SUBJECT: FUSELAGE - Section 48 - Station 2370 Pivot Bulkhead Forward Outer Chord -
Inspection and Repair
THIS BULLETIN 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 SERVICE BULLETIN TO
THE NEW OPERATOR. IF APPLICABLE SPARES HAVE BEEN SOLD, SEND THIS SERVICE BULLETIN TO
THE NEW OWNER.
1.    PLANNING INFORMATION
A. Effectivity
1. Airplanes
This service bulletin is applicable to 777-200/-300 Airplanes, line numbers 1-244 in 2 Groups. The
Variable Numbers and Group Information for the applicable airplanes is given below. An equivalent
change is on subsequent production airplanes. Refer to PRR 62777-97S for data about this change.
Refer to Service Bulletin Index D624W001 Part 3 for Airplane Variable Number, Line Number, and
Serial Number data.
DESCRIPTIONCONFIGURATIONGROUP
777 Airplanes, line numbers 1 through 40-1
777 Airplanes, line numbers 41 through 244-2
Airplane Models:
777-200, 777-300
GroupVariable Number
1WA001 - WA017
1WA076 - WA080
1WA086 - WA087
2WA088 - WA093
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GroupVariable Number
1WA101 - WA104
1WA116 - WA117
2WA118 - WA119
1WA131 - WA135
2WA136 - WA137
1WA171 - WA173
2WA174 - WA175
1WA196 - WA197
2WA198
2WA206 - WA212
2WA221 - WA223
2WA231 - WA232
2WA241 - WA245
2WB001 - WB020
2WB031
2WB051 - WB072
2WB101 - WB106
2WB121 - WB125
2WB131 - WB133
2WB151 - WB153
2WB161 - WB171
2WB181 - WB188
2WB231 - WB235
2WB271 - WB272
2WB276 - WB286
2WB291 - WB297
2WB306 - WB307
2WB311 - WB318
2WB336 - WB337
2WB366
2WB371 - WB383
2WB406
2WB411 - WB413
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GroupVariable Number
2WB416 - WB426
2WB446 - WB448
2WB501 - WB506
2WB531 - WB535
2WB551 - WB553
2WB591 - WB595
2WB601 - WB602
2WB611 - WB615
2. Spares Affected
None.
B. Concurrent Requirements
None.
C. Reason
This service bulletin is sent to give instructions for inspections of the left and right side forward outer
chords of the Body Station (STA) 2370 pivot bulkhead for cracks. Cracks in the STA 2370 pivot bulkhead
forward outer chords that are not found and repaired can become large and result in a severed forward
outer chord. Since the horizontal stabilizer is attached to the STA 2370 bulkhead at two pivot locations,
this damage could cause the loss of horizontal stabilizer control, resulting in loss of controllability of
the airplane.
Two operators have reported finding cracks in the outer flanges of the left and right side forward outer
chords of the STA 2370 pivot bulkhead on a total of eleven airplanes. The cracks were fatigue cracks
caused by a stress concentration which is generated at the transition radius of the forward outer flange
of the chord prior to the chord splice at the upper longeron.
Accomplishment of the inspections in this service bulletin will help ensure that STA 2370 pivot bulkhead
forward outer chord cracks are found and repaired before they can become large and result in damage
that could result in the loss of horizontal stabilizer control.
Boeing Service Bulletin (SB) 777-53-0076 gives instructions for a modification that is terminating action
to the repeat inspections given in this service bulletin.
The table below shows the crack findings and related service data that have been reported to Boeing.
Service History
Crack Length (Inches)Crack LocationFlight HoursFlight CyclesModel
1.4 and 3.3Left Side39,14231,384777-200
2.93Right Side
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Service History
Crack Length (Inches)Crack LocationFlight HoursFlight CyclesModel
2.3Left Side39,79731,504777-200
2.2Right Side
2.5Left Side38,75832,181777-200
2.3Right Side
2.5Left Side37,18229,383777-200
2.5Right Side
2.2Left Side34,29124,653777-300
2.2Right Side
2.25Left Side40,07435,011777-200
2.2Right Side
2.5Left Side33,56824,251777-300
2.03Right Side
2.35Left Side38,45530,462777-200
2.2Right Side
2.2Left Side39,16630,826777-200
2.4Right Side
2.5Left Side40,58833,809777-200
2.4Right Side
1.2Left Side63,94017,530777-300
1.65Right Side
Boeing Fleet Team Digest (FTD) 777 FTD 53-13001 is related to this service bulletin.
Boeing Service Related Problem (SRP) 777-SRP-53-0455 is related to this service bulletin.
As a part of a service bulletin validation program, this inspection was completed on airplane WA174
by Service Bulletin 777-53A0075 Original Issue before the release of Revision 1 of this service bulletin.
The inspection completed on airplane WA174 by Service Bulletin 777-53A0075 Original Issue is
equivalent to the release of Revision 1 of this service bulletin. Airplane WA174 has the configuration
of a Group 2 airplane.
Revision 1 is sent to make changes identified during the validation of the Original Issue of this service
bulletin and to clarify or correct issues identified by operators since the Original Issue.
D. Description
Do a Detailed and HFEC inspection of the Station 2370 pivot bulkhead forward chord in accordance
with PART 1, for any crack.
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If any crack is found, and no crack found is greater than 0.160 inch, do one of the following options on
the affected side of the airplane:
1. Do the terminating action in accordance with SB 777-53-0076.
2. Do the repair of the Station 2370 pivot bulkhead forward chord in accordance with PART 2 and
the post-repair Detailed and HFEC inspection in accordance with PART 3.
If any crack found is greater than 0.160 inch, do the terminating action in accordance with SB
777-53-0076.
If no crack is found, repeat PART 1, or do the terminating action in accordance with SB 777-53-0076.
Revision 1 - Effects of this Revision on airplanes on which Original Issue was previously done:
None.
The work in this service bulletin is done in the maintenance zone(s) given below.
Group 1:
Affected Maintenance Zones
ZoneModel
313, 314777-200
Group 2:
Affected Maintenance Zones
ZoneModel
313, 314777-200, 777-300
E. Compliance
Federal Aviation Administration (FAA) Notice of Proposed Rule Making NPRM 2015-NM-026-AD, is
related to this service bulletin.
Do the required actions in accordance with Paragraph 3. Accomplishment Instructions.
When more than one OPTION is given for a CONDITION, do only one of the OPTION numbers. When
more than one ACTION is given for a CONDITION number or an OPTION number, do all of the ACTION
numbers for that CONDITION number or OPTION number.
Logic diagrams showing compliance tasks and compliance times are included as aids in APPENDIX
A and APPENDIX B.
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The conditions and associated actions given in the compliance tables below can be different on the
left and right sides of the airplane. The actions done must obey the compliance times shown in the
compliance tables for each side of the airplane. Because the conditions found may not be the same
on both sides of the airplane, the required actions may be different between the left and right side of
the airplane and can be done independently.
Table 1: Detailed and HFEC Inspection of the Station 2370 Pivot Bulkhead Forward Chord:
Repeat Interval
(Not to Exceed)
Compliance Time (Whichever
Occurs Later)
ActionCondition
-Within 4,000
flight cycles or
1,125 days,
whichever oc-
curs first, after
the Original Is-
sue date of this
Service Bulletin.
Before 16,000
total flight cycles
Do PART 1: STATION
2370 PIVOT BULKHEAD
FORWARD CHORD -
DET AND HFEC INSPEC-
TION for any crack.
All Airplanes
12,000 flight cycles-OPTION 1:CONDITION 1: NO FOR-
WARD CHORD CRACK IS
FOUND
(a)Repeat PART 1: STA-
TION 2370 PIVOT
BULKHEAD FORWARD
CHORD - DET AND
HFEC INSPECTION for
any crack.
(a)Before further flightOPTION 2:
Do the terminating modifi-
cation in accordance with
Boeing Service Bulletin
777-53-0076. (a)
-Before further flightOPTION 2:CONDITION 2: ANY FOR-
WARD CHORD CRACK IS
FOUND, AND NO CRACK
FOUND IS GREATER
THAN 0.160 INCH
Do the terminating modifi-
cation in accordance with
Boeing Service Bulletin
777-53-0076. (a)
-Before further flightOPTION 3 (ACTION 1):
Do PART 2: STATION
2370 PIVOT BULKHEAD
FORWARD CHORD -
SMALL CRACK REPAIR.
-Refer to Table 2OPTION 3 (ACTION 2):
Do PART 3: STATION
2370 PIVOT BULKHEAD
FORWARD CHORD -
POST-REPAIR DET AND
HFEC INSPECTION.
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Table 1: Detailed and HFEC Inspection of the Station 2370 Pivot Bulkhead Forward Chord:
Repeat Interval
(Not to Exceed)
Compliance Time (Whichever
Occurs Later)
ActionCondition
-Before further flightDo the terminating modifi-
cation in accordance with
Boeing Service Bulletin
777-53-0076. (a)
CONDITION 3: ANY FOR-
WARD CHORD CRACK
FOUND IS GREATER
THAN 0.160 INCH.
-Before further flightContinue to do the small
crack repair in accor-
dance with PART 2:
STATION 2370 PIVOT
BULKHEAD FORWARD
CHORD - SMALL
CRACK REPAIR.
CONDITION 6: NO FOR-
WARD CHORD UPPER
LOCATION OR ADJA-
CENT STRUCTURE
CRACK IS FOUND
-Before further flightACTION 1: Contact The
Boeing Company for re-
pair instructions and do
the repair.
CONDITION 7: ANY FOR-
WARD CHORD UPPER
LOCATION OR ADJA-
CENT STRUCTURE
CRACK IS FOUND -Before further flightACTION 2: Continue to
do the small crack repair
in accordance with PART
2: STATION 2370 PIVOT
BULKHEAD FORWARD
CHORD - SMALL
CRACK REPAIR.
(a) Modification in accordance with Boeing Service Bulletin 777-53-0076 is terminating action to the repeat
inspections in this service bulletin.
Table 2: Post-Repair Detailed and HFEC Inspection of the STA 2370 Pivot Bulkhead Forward
Chord:
Repeat Interval
(Not to Exceed)
Compliance TimeActionCondition
-Within 12,000 flight
cycles after installa-
tion of the repair in
accordance with
PART 2: STATION
2370 PIVOT
BULKHEAD FOR-
WARD CHORD -
SMALL CRACK
REPAIR
Do PART 3: STATION
2370 PIVOT BULKHEAD
FORWARD CHORD -
POST-REPAIR DET AND
HFEC INSPECTION for
any crack.
All airplanes previously re-
paired in accordance with
PART 2: STATION 2370
PIVOT BULKHEAD FOR-
WARD CHORD - SMALL
CRACK REPAIR
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Table 2: Post-Repair Detailed and HFEC Inspection of the STA 2370 Pivot Bulkhead Forward
Chord:
Repeat Interval
(Not to Exceed)
Compliance TimeActionCondition
12,000 flight cycles-OPTION 4: Repeat PART
3: STATION 2370 PIVOT
BULKHEAD FORWARD
CHORD -POST-REPAIR
DET AND HFEC INSPEC-
TION for any crack.
CONDITION 4: NO FOR-
WARD CHORD CRACK IS
FOUND DURING POST-
REPAIR INSPECTION
(a)
(a)Before further flightOPTION 2: Do the termi-
nating modification in ac-
cordance with Boeing
Service Bulletin 777-53-
0076. (a)
-Before further flightDo the terminating modifi-
cation in accordance with
Boeing Service Bulletin
777-53-0076. (a)
CONDITION 5: ANY FOR-
WARD CHORD CRACK IS
FOUND DURING POST-
REPAIR INSPECTION
(a) Modification in accordance with Boeing Service Bulletin 777-53-0076 is terminating action
to the repeat inspections in this service bulletin.
NOTE: PART 1: STATION 2370 PIVOT BULKHEAD FORWARD CHORD - DET AND HFEC
INSPECTION is for both sides of the airplane.
PART 2: STATION 2370 PIVOT BULKHEAD FORWARD CHORD - SMALL CRACK REPAIR
is for one side of the airplane. It is possible to have an airplane with PART 2: STATION 2370
PIVOT BULKHEAD FORWARD CHORD - SMALL CRACK REPAIR done on both sides.
PART 3: STATION 2370 PIVOT BULKHEAD FORWARD CHORD - POST-REPAIR DET AND
HFEC INSPECTION is for one side of the airplane. It is possible to have an airplane with
PART 3: STATION 2370 PIVOT BULKHEAD FORWARD CHORD - POST-REPAIR DET AND
HFEC INSPECTION done on both sides.
PART 4: STATION 2370 PIVOT BULKHEAD FORWARD CHORD AND ADJACENT
STRUCTURE - HFEC AND DET INSPECTION is for one side of the airplane. It is possible
to have an airplane with PART 4: STATION 2370 PIVOT BULKHEAD FORWARD CHORD
AND ADJACENT STRUCTURE - HFEC AND DET INSPECTION done on both sides.
F. Approval
This service bulletin was examined by the Federal Aviation Administration (FAA). The changes specified
in this service bulletin comply with the applicable regulations and are FAA approved, as well as European
Aviation Safety Agency (EASA)/Joint Aviation Authorities (JAA) approved for all EASA/JAA approved
airplanes listed in the service bulletin effectivity. This service bulletin and its approval were based on
the airplane in its original Boeing delivery configuration or as modified by other approved Boeing
changes.
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If an airplane has a non-Boeing modification or repair that affects a component or system also affected
by this service bulletin, the operator is responsible for obtaining appropriate regulatory agency approval
before incorporating this service bulletin.
G. Manpower
The tables below show an estimate of the task hours necessary to do this inspection for each airplane.
This estimate is for direct labor only, done by an experienced crew. Adjust the estimate with operator
task hour data if necessary. The estimate does not include lost time. These are some examples of lost
time:
• Time to adjust to the workplace
• Time to schedule the work
• Time to inspect the work
• Time to cure the materials
• Time to make the parts
• Time to find the tools.
Table 1: Manpower Information for PART 1: STATION 2370 PIVOT BULKHEAD FORWARD
CHORD - DET AND HFEC INSPECTION
Elapsed HoursTask HoursNumber of PersonsTask
Open Access
2.002.001FIGURE 1
2,002.001FIGURE 2
PART 1: STATION 2370 PIVOT BULKHEAD FORWARD CHORD - DET AND
HFEC INSPECTION
1.251.251FIGURE 3
1.251.251FIGURE 4
Close Access
2.004.002FIGURE 5
2.004.002FIGURE 6
10.5014.50TOTAL FOR EACH AIRPLANE
Group 1:
Table 2: Manpower Information for PART 2: STATION 2370 PIVOT BULKHEAD FORWARD
CHORD - SMALL CRACK REPAIR
Elapsed HoursTask HoursNumber of PersonsTask
4.008.002FIGURE 7 (or FIG-
URE 8) (a)
1.501.501FIGURE 11 (or FIG-
URE 12) (a)
1.751.751FIGURE 13 (or FIG-
URE 14) (a)
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Group 1:
Table 2: Manpower Information for PART 2: STATION 2370 PIVOT BULKHEAD FORWARD
CHORD - SMALL CRACK REPAIR
Elapsed HoursTask HoursNumber of PersonsTask
14.8029.602FIGURE 15 (or FIG-
URE 16) (a)
2.004.002FIGURE 23 (or FIG-
URE 24) (a)
24.0544.85TOTAL FOR ONE SIDE OF THE AIRPLANE
(b)
(a) Figure 7, Figure 11, Figure 13, Figure 15 and Figure 23 are for the left side of
the airplane. Figure 8, Figure 12, Figure 14, Figure 16 and Figure 24 are for
the right side of the airplane.
(b) This table shows the manpower information for small crack repair in accordance
with PART 2: STATION 2370 PIVOT BULKHEAD FORWARD CHORD -
SMALL CRACK REPAIR, on one side of the airplane. If both sides of the air-
plane are repaired in accordance with PART 2: STATION 2370 PIVOT
BULKHEAD FORWARD CHORD - SMALL CRACK REPAIR, multiply the total
manpower information by two, to obtain the total manpower for both sides of
the airplane.
Group 2:
Table 3: Manpower Information for PART 2: STATION 2370 PIVOT BULKHEAD FORWARD
CHORD - SMALL CRACK REPAIR
Elapsed HoursTask HoursNumber of PersonsTask
4.008.002FIGURE 9 (or FIG-
URE 10) (a)
1.501.501FIGURE 11 (or FIG-
URE 12) (a)
14.8029.602FIGURE 17 (or FIG-
URE 18) (a)
2.004.002FIGURE 23 (or FIG-
URE 24) (a)
22.3043.10TOTAL FOR ONE SIDE OF THE AIRPLANE
(b)
(a) Figure 9, Figure 11, Figure 17 and Figure 23 are for the left side of the airplane.
Figure 10, Figure 12, Figure 18 and Figure 24 are for the right side of the air-
plane.
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Group 2:
Table 3: Manpower Information for PART 2: STATION 2370 PIVOT BULKHEAD FORWARD
CHORD - SMALL CRACK REPAIR
Elapsed HoursTask HoursNumber of PersonsTask
(b) This table shows the manpower information for small crack repair in accordance
with PART 2: STATION 2370 PIVOT BULKHEAD FORWARD CHORD -
SMALL CRACK REPAIR, on one side of the airplane. If both sides of the air-
plane are repaired in accordance with PART 2: STATION 2370 PIVOT
BULKHEAD FORWARD CHORD - SMALL CRACK REPAIR, multiply the total
manpower information by two, to obtain the total manpower for both sides of
the airplane.
Table 4: Manpower Information for PART 3: STATION 2370 PIVOT BULKHEAD FORWARD
CHORD - POST-REPAIR DET AND HFEC INSPECTION
Elapsed HoursTask HoursNumber of PersonsTask
Open Access
2.002.001FIGURE 25
2.002.001FIGURE 26
DET and HFEC Inspection
1.251.251FIGURE 19
1.251.251FIGURE 20
Close Access
2.002.002FIGURE 21
2.002,002FIGURE 22
8.5010.50TOTAL FOR EACH AIRPLANE
NOTE: PART 1: STATION 2370 PIVOT BULKHEAD FORWARD CHORD - DET AND HFEC
INSPECTION is for both sides of the airplane.
PART 2: STATION 2370 PIVOT BULKHEAD FORWARD CHORD - SMALL CRACK REPAIR
is for one side of the airplane. It is possible to have an airplane with PART 2: STATION 2370
PIVOT BULKHEAD FORWARD CHORD - SMALL CRACK REPAIR done on both sides.
PART 3: STATION 2370 PIVOT BULKHEAD FORWARD CHORD - POST-REPAIR DET AND
HFEC INSPECTION is for one side of the airplane. It is possible to have an airplane with
PART 3: STATION 2370 PIVOT BULKHEAD FORWARD CHORD - POST-REPAIR DET AND
HFEC INSPECTION done on both sides.
PART 4: STATION 2370 PIVOT BULKHEAD FORWARD CHORD AND ADJACENT
STRUCTURE - HFEC AND DET INSPECTION is for one side of the airplane. It is possible
to have an airplane with PART 4: STATION 2370 PIVOT BULKHEAD FORWARD CHORD
AND ADJACENT STRUCTURE - HFEC AND DET INSPECTION done on both sides.
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H. Weight and Balance Changes
Change in Moment
(Pound-Inches)
Change in Weight
(Pounds)Airplane
+1,183.5+0.5777-200 - Repaired
on one side
+2,367.0+1.0777-200 - Repaired
on both sides
+1,278.0+0.5777-300 - Repaired
on one side
+2,556.0+1.0777-300 - Repaired
on both sides
I. Electrical Load Data
Not changed.
J. References
1. Existing Data:
a. Engineering Change Memo PRR 62777-97S
b. Boeing Service Bulletin 777-53-0076
c. Boeing Service Letter 777-SL-51-013
d. Boeing Service Related Problem (SRP) 777-SRP-53-0455
e. Federal Aviation Administration (FAA) Notice of Proposed Rule Making (NPRM)
2015-NM-026-AD
f. Service Bulletin Index D624W001
g. Standard Overhaul Practices Manual (SOPM) 20-10-03, 20-41-02, 20-41-05, 20-43-03,
20-50-01, 20-50-10, 20-50-19
h. 777 Aircraft Maintenance Manual (AMM) 07-11-01, 55-17-01
i. 777 Fleet Team Digest (FTD) 53-13001
j. 777 Non-Destructive Testing (NDT) Manual Part 6, 51-00-01, Part 6, 51-00-02
k. 777-200 Structural Repair Manual (SRM) 51-10-02, 51-20-01
l. 777-300 Structural Repair Manual (SRM) 51-10-02, 51-20-01
2. Data Supplied with this Service Bulletin:
None.
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3. Installation Drawings Used in the Preparation of this Service Bulletin:
TitleDrawing Number
Bulkhead Instl - Upr, Pivot and Skin, STA 2370148W2010
Fairing Instl - Stabilizer Seal, UPR148W2910
Bulkhead Instl - Pivot, Integration, STA 2370148W9700
The table above lists applicable drawings used to prepare this service bulletin. The drawings are
not necessary to make the specified changes, and are not supplied with this service bulletin. The
drawings may not be applicable to all airplane configurations or operators.
K. Publications Affected
1. Publications:
Chapter-SectionPublication
53-80777 Structural Repair Manual
2. Damage Tolerance Based Structural Inspections:
Boeing has evaluated the repairs and/or changes in this service bulletin for effects on Fatigue
Critical Structure (FCS) and for changes to Damage Tolerance Inspections (DTI) required in the
Maintenance Program. This service bulletin affects FCS. DTI requirements for the structure affected
are contained in Paragraph 1.E., Compliance of this service bulletin.
L. Interchangeability and Intermixability of Parts
Accomplishment of this service bulletin does not affect interchangeability or intermixability of parts.
M. Software Accomplishment Summary
Not affected.
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2.    MATERIAL INFORMATION
A. Material - Price and Availability
Boeing can supply the kits shown in Paragraph 2.C., Parts Necessary for Each Airplane. Operators
are encouraged to share schedule requirements with Boeing for incorporation of the service bulletin.
The kits are subject to the terms and conditions of the Boeing standard purchase order acknowledgment.
Prices are in United States Dollars. Terms: Net 30 days.
Reference this service bulletin and submit your purchase order by one of these methods:
1. Order on-line via ATA Spec 2000 or The Boeing PART Page
2. Fax to (206) 662-7145
REFER TO THE BOEING PART PAGE ON MYBOEINGFLEET.COM OR CONTACT FIRST RESPONDER
AT FR@BOEING.COM FOR THE LATEST REORDER LEAD TIME (ROLT) AND PRICE INFORMATION
Unit Price as of
the Revision 1
date of this Ser-
vice Bulletin (US
Dollars)
ROLT as of the
Revision 1 date of
this Service Bul-
letin (Calendar
Days)
QTYDateNameKit Number
241.0026611January 12,
2016
Top Kit - STA 2370
Pivot Bulkhead Forward
Outer Chord - Inspec-
tion Restoration
005W0016-10
10February 9,
2016
10March 8, 2016
13,574.0052510January 12,
2016
Top Kit - STA 2370
Pivot Bulkhead Forward
Outer Chord, Left -
Small Crack
005W0016-11
(a)
13,574.0079010January 12,
2016
Top Kit - STA 2370
Pivot Bulkhead Forward
Outer Chord, Right -
Small Crack
005W0016-12
(b)
(a) This top kit is for the repair on the left side of the airplane.
(b) This top kit is for the repair on the right side of the airplane.
Operators are encouraged to complete the survey provided in APPENDIX C of this service bulletin to
help Boeing predict the quantity and timing of the Boeing Supplied Kits/Parts.
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B. Industry Support Information
Boeing warranty remedies are available for 777 airplanes in warranty as of November 20, 2013. For
task hour reimbursement for airplanes in warranty as of that date, send a warranty claim to Boeing
Fleet Support Contracts - Warranty. The kits for airplanes in warranty as of that date will be supplied
at no charge. Send a purchase order for the kits to Boeing Material Management. Please refer to this
service bulletin number and reference the airplane variable numbers in your purchase order. The
warranty remedies will expire eight years from the original issue date of this service bulletin.
C. Parts Necessary for Each Airplane
1. Kits/Parts
To get the kits/parts shown below, refer to Paragraph 2.A., Material - Price and Availability.
NOTE: One top kit and the items shown in Paragraph 2.C.2., Parts and Materials Supplied by
the Operator, are necessary for each airplane, except as noted in Paragraph 2.A., Material
- Price and Availability.
ALL
Kit 005W0016
NotesExisting Part
Number
NameQtyNew Part Number
-12-11-10
(a)-Top Kit - STA 2370
Pivot Bulkhead
Forward Outer
Chord - Inspection
Restoration
..-005W0016-10
(b)-Top Kit - STA 2370
Pivot Bulkhead
Forward Outer
Chord, Left - Small
Crack Repair
.-.005W0016-11
(c)-Top Kit - STA 2370
Pivot Bulkhead
Forward Outer
Chord, Right- Small
Crack Repair
-..005W0016-12
--SHIM11.148W0015-12
--SHIM11.148W0015-13
--SHIM22.148W0015-14
(d) (e)
(f)
148W2204-1
(Group 1)
SPLICE ANGLE.1.148W2204-5
148W2204-3
(Group 2)
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ALL
Kit 005W0016
NotesExisting Part
Number
NameQtyNew Part Number
-12-11-10
(d) (e)
(f)
148W2204-2
(Group 1)
SPLICE ANGLE1..148W2204-6
148W2204-4
(Group 2)
--SHIM LAMINATED11.148W7143-5
--SHIM LAMINATED11.148W7143-6
--SHIM LAMINATED11.148W7143-7
--SHIM LAMINATED11.148W7143-11
--SHIM LAMINATED11.148W7143-13
--RADIUS FILLER11.148W9710-15
(g)-BOLT, PROTRUD-
ING HD
66.BACB30MY10K10X
(g)-BOLT, PROTRUD-
ING HD
66.BACB30MY10K13X
(g)-BOLT, PROTRUD-
ING HD
88.BACB30MY10K7X
(g)-BOLT, PROTRUD-
ING HD
1414.BACB30MY8K11X
(g)-BOLT, PROTRUD-
ING HD
1611.BACB30MY8K4X
(g)-BOLT, PROTRUD-
ING HD
811.BACB30MY8K5X
(g)-BOLT, PROTRUD-
ING HD
1818.BACB30MY8K6X
(g)-BOLT, PROTRUD-
ING HD
88.BACB30MY8K7X
(g)-BOLT, PROTRUD-
ING HD
55.BACB30MY8K8X
(g)-BOLT, PROTRUD-
ING HD
11.BACB30MY8K9X
(g)-BOLT, 100 DEG
HEX DR
224BACB30NW6K5X
(g)-BOLT, 100 DEG
HEX DR
2828.BACB30NW8K10X
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ALL
Kit 005W0016
NotesExisting Part
Number
NameQtyNew Part Number
-12-11-10
(g)-BOLT, 100 DEG
HEX DR
44.BACB30NW8K12X
(g)-BOLT, 100 DEG
HEX DR
3314BACB30NW8K5X
(g)-BOLT, 100 DEG
HEX DR
112BACB30NW8K6X
(g)-BOLT, 100 DEG
HEX DR
33.BACB30NW8K7X
(g)-BOLT, 100 DEG
HEX DR
55.BACB30NW8K8X
(g)-BOLT, 100 DEG
HEX DR
31318BACB30NW8K9X
(g)-BOLT, PROTRUD-
ING HD
33.BACB30NX10K11X
(g)-BOLT, PROTRUD-
ING HD
1313.BACB30NX10K14X
(g)-BOLT, PROTRUD-
ING HD
44.BACB30NX6K5X
(g)-BOLT, 100 DEG
HEX D
1212.BACB30NZ10K15X
(g)-BOLT, 100 DEG
HEX DR
1616.BACB30NZ10K16X
(g)-BOLT, 100 DEG
HEX DR
1010.BACB30NZ8K12X
(g)-BOLT, HEX DRIVE1212.BACB30YN10K15X
(g)-BOLT, HEX DRIVE1616.BACB30YN10K16X
(g)-BOLT, HEX DRIVE88.BACB30YN8K12X
--COLLAR4444.BACC30BH10
--COLLAR1010.BACC30BH8
--COLLAR2020.BACC30M10
--COLLAR664BACC30M6
--COLLAR13213224BACC30M8
--SELF-LOCKING
NUT
22.BACN10HR12CD
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### Page 33

ALL
Kit 005W0016
NotesExisting Part
Number
NameQtyNew Part Number
-12-11-10
--SELF-LOCKING
NUT
22.BACN10HR162CD
--SELF-LOCKING
NUT
55.BACN10HR6CD
--NUT33.BACN10HR8CD
--NUT1616.BACN10YR4CD
--NUT2828.BACN10YR5CD
(g)-RIVET, 100 DEG336BACR15CE5KE5
(g)-RIVET, 100 DEG6612BACR15CE5KE6
(g)-RIVET, 100 DEG112BACR15CE5KE8
(g)-RIVET2727.BACR15FV81KE13
--SHIM, LAMINAT-
ED
11.BACS40R007B064F
--SHIM, LAMINAT-
ED
11.BACS40R007B077F
--SHIM, LAMINAT-
ED
11.BACS40R008B041F
--SHIM, LAMINAT-
ED
11.BACS40R008B062F
--SHIM, LAMINAT-
ED
11.BACS40R016B037F
--SHIM, LAMINAT-
ED
11.BACS40R017B037F
--SHIM, LAMINAT-
ED
11.BACS40R019B056F
--SHIM, LAMINAT-
ED
11.BACS40R021B049F
--SHIM, LAMINAT-
ED
11.BACS40R023B053F
--SHIM,LAMINATED11.BACS40R029B065F
--SHIM-LAMINATED11.BACS40R033B052F
--WASHER, PLAIN22.BACW10BP12CD
--WASHER, PLAIN22.BACW10BP12DP
--WASHER, PLAIN22.BACW10BP16CD
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### Page 34

ALL
Kit 005W0016
NotesExisting Part
Number
NameQtyNew Part Number
-12-11-10
--WASHER, PLAIN22.BACW10BP16DP
--WASHER, PLAIN88.BACW10BP41DP
--WASHER, PLAIN55.BACW10BP6CD
--WASHER55.BACW10BP6DP
--WASHER33.BACW10BP8CD
--WASHER33.BACW10BP8DP
--WASHER88.NAS1149D0432J
--WASHER88.NAS1149D0463J
--WASHER2828.NAS1149D0532J
--WASHER2828.NAS1149D0563J
(a) This top kit is for access restoration after inspection and no crack findings.
(b) This top kit is for the repair on the left side of the airplane.
(c) This top kit is for the repair on the right side of the airplane.
(d) Discard the existing part.
(e) This part is used in production.
(f) You cannot use the existing part to replace the new or changed part.
(g) If grip length shown is not available at Boeing, fasteners supplied in kits may be one
grip length longer than indicated. Also, if any fasteners part numbers listed are not
available or have been superseded, substitute fasteners may be supplied in kits.
2. Parts and Materials Supplied by the Operator
The following parts or materials are necessary to do the change in this service bulletin. Parts and
materials in the manuals given in Paragraph 1.J., References, can also be necessary. Examine
operator part and material supply to make sure all necessary parts and materials are available.
NotesNameQTYPart Number /
Specification
(a)Corrosion Inhibiting Compound1 pintBMS 3-23 (BMS 3-
29 and BMS 3-35
optional)
(a)Sealant1 pintBMS 5-95
(a)Primer1 pintBMS 10-11, Type I
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NotesNameQTYPart Number /
Specification
(a) Refer to the Qualified Products List at the end of the Boeing Material Specification (BMS)
for supplier data.
3. Parts Modified and Reidentified
The parts shown below are changed as shown in this service bulletin. The quantity (QTY) is the
number of parts changed on each airplane.
Group 1:
NotesNew Part NumberNameQTYExisting Part Number
(c) (e)(d)SPLICE ANGLE1148W2204-5 (a)
(c) (e)(d)SPLICE ANGLE1148W2204-6 (b)
(a) This part is included in top kit 005W0016-11.
(b) This part is included in top kit 005W0016-12.
(c) Make the change in accordance with this service bulletin.
(d) There is no equivalent Boeing part number for the changed part. Identify on the part that
the change in accordance with this service bulletin was made.
(e) This part is not used in production.
Group 2:
None.
4. Parts Removed and Not Replaced
None.
D. Parts Necessary to Change Spares
None.
E. Special Tooling - Price and Availability
None.
F. Special Tooling Necessary to do this Service Bulletin
No special tools or equipment are necessary to do the change in this service bulletin. But, maintenance
and overhaul tools in the manuals given in Paragraph 1.J., References, can be necessary. Examine
operator tool supply to make sure all necessary tools are available.
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BLANK PAGE

### Page 37

3.    ACCOMPLISHMENT INSTRUCTIONS
A. GENERAL INFORMATION
CAUTION: KEEP THE WORK AREA, WIRES AND ELECTRICAL BUNDLES CLEAN OF METAL
PARTICLES OR CONTAMINATION WHEN YOU USE TOOLS. UNWANTED MATERIAL,
METAL PARTICLES OR CONTAMINATION CAUGHT IN WIRE BUNDLES CAN CAUSE
DAMAGE TO THE BUNDLES. DAMAGED WIRE BUNDLES CAN CAUSE SPARKS OR
OTHER ELECTRICAL DAMAGE.
NOTE: 1. Manual titles are referred to by acronyms. Refer to Paragraph 1.J., References, for
definition of the acronyms.
2. Obey all of the warnings and cautions given in the specified manual sections.
3. Unless shown differently, these dimensions and tolerances are used:
– Linear dimensions are in inches
– Tolerance on linear dimensions, other than rivet and bolt edge margins, is plus
or minus 0.03 inch
– Tolerance on rivet and bolt edge margin is plus or minus 0.05 inch
– Angular tolerance is plus or minus 2 degrees
– Hole dimensions for standard solid rivets and fasteners are in Structural Repair
Manual (SRM) Chapter 51
– Torque Values:
— Values for structural fasteners are given in 777 Structural Repair Manual,
Chapter 51.
— Values for airframe maintenance tasks are included in Chapter 20 of 777
Airplane Maintenance Manual (AMM).
— Values for electrical maintenance tasks are included in Chapter 20 of
Standard Wiring Practices Manual (SWPM).
— Values for engine maintenance tasks are included in Chapter 70 of 777
Airplane Maintenance Manual (AMM).
— Non-standard torque values for maintenance tasks are included in the
applicable installation step.
4. Use the approved fastener, process and material substitutions in accordance with
SRM Chapter 51.
5. If the length of any fastener specified in this service bulletin does not meet installation
standards given in SRM Chapter 51, then a fastener of the same specification, or
an approved substitute, with a length which meets the installation standards given
in SRM Chapter 51 may be used. In addition, washers may be installed for fastener
grip length in accordance with SRM Chapter 51. Refer to SOPM 20-50-01 for alternate
full threaded fasteners (screws) needed for installation in this service bulletin.
6. A Detailed Inspection (DET) is defined as: An intensive examination of a specific
item, installation, or assembly to detect damage, failure, or irregularity. Available
lighting is normally supplemented with a direct source of good lighting at an intensity
deemed appropriate. Inspection aids such as mirrors, magnifying lenses, etc. may
be necessary. Surface cleaning and elaborate procedures may be required.
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7. HFEC is used for a High Frequency Eddy Current Inspection.
8. These work instructions refer to procedures included in other Boeing documents.
When the words "refer to" are used and the operator has an accepted alternative
procedure, the accepted alternative procedure can be used. When the words "in
accordance with" are included in the instruction, the procedure in the Boeing document
must be used.
9. Boeing Service Letter 777-SL-51-013, Damage Reporting and Repair Plan/Design
Guidelines, is an acceptable procedure to request information from Boeing for
additional structural repair instructions. The Service Letter describes what information
must be provided to Boeing before a structural repair can be provided.
10. Refer to APPENDIX A and APPENDIX B for logic diagram(s). Logic diagrams are
provided as an aid only. Information contained in Paragraph 1.E., Compliance is the
primary source for compliance times. Information in Paragraph 3.B., Work Instructions
is the primary source for tasks required for compliance.
11. The instructions in Paragraph 3.B., Work Instructions and the figures can include
operation of tools or test equipment. Boeing Engineering Tool Drawings, the Illustrated
Tool and Equipment Manual, and the Special Tool and Ground Handling Drawing
Index contain data on versions of the tools or test equipment that you can use. It is
permitted to use replaced tools. It is not permitted to use superseded tools.
12. If it is necessary to remove more parts for access, you can remove those parts. If
you can get access without removing identified parts, it is not necessary to remove
all of the identified parts. Jacking and shoring limitations must be observed.
13. Where the work instructions include installation of a kept part, a new or serviceable
part with the same part number can be installed as an alternative to the kept part.
14. Use of colors in Figures is based on guidance from the ATA e-Business Program
(ATA) iSpec 2200.
15. When more than one OPTION is given for a CONDITION, do only one of the OPTION
numbers. When more than one ACTION is given for a CONDITION number or an
OPTION number, do all of the ACTION numbers for that CONDITION number or
OPTION number.
16. The compliance times for the actions in Paragraph 3.B., WORK INSTRUCTIONS
are in Paragraph 1.E., Compliance.
17. The conditions and associated actions given in Paragraph 3.B., Work Instructions
can be different on the left and right sides of the airplane. Because the conditions
found may not be the same on both sides of the airplane, the required actions may
be different between the left and right side of the airplane and can be done
independently.
18. Some steps in the Work Instructions are labeled as Required for Compliance (RC).
If this service bulletin is mandated by an Airworthiness Directive (AD), then the steps
labeled as RC, including sub-steps under an RC step and any figures identified in
an RC step, must be done to comply with the AD. An Alternative Method of
Compliance (AMOC) is required for any deviations to RC steps, including sub-steps
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and identified figures. Steps not labeled as RC may be deviated from using accepted
methods in accordance with the operator's maintenance or inspection program without
obtaining approval of an AMOC. This is provided that the RC steps, including
sub-steps and identified figures, can still be done as specified, and the airplane can
be put back in an airworthy condition.
B. WORK INSTRUCTIONS
1. Remove the skin panels in accordance with the figures below:
Right SideLeft Side
FIGURE 2FIGURE 1
2. Do PART 1: STATION 2370 PIVOT BULKHEAD FORWARD CHORD - DET AND HFEC
INSPECTION, for any crack.
a. CONDITION 1: NO FORWARD CHORD CRACK IS FOUND
(1) OPTION 1: Repeat PART 1: STATION 2370 PIVOT BULKHEAD FORWARD CHORD -
DET AND HFEC INSPECTION for any crack.
(2) OPTION 2: Do the terminating modification in accordance with Boeing Service Bulletin
777-53-0076.
b. CONDITION 2: ANY FORWARD CHORD CRACK IS FOUND, AND NO CRACK FOUND IS
GREATER THAN 0.160 INCH
(1) OPTION 2: Do the terminating modification in accordance with Boeing Service Bulletin
777-53-0076.
(2) OPTION 3:
(a) OPTION 3 (ACTION 1): Do PART 2: STATION 2370 PIVOT BULKHEAD FORWARD
CHORD - SMALL CRACK REPAIR.
NOTE: PART 2: STATION 2370 PIVOT BULKHEAD FORWARD CHORD - SMALL
CRACK REPAIR can be done on the left and right side of the airplane at
the same time.
(b) OPTION 3 (ACTION 2): Do PART 3: STATION 2370 PIVOT BULKHEAD FORWARD
CHORD - POST-REPAIR DET AND HFEC INSPECTION.
1) CONDITION 4: NO FORWARD CHORD CRACK IS FOUND DURING
POST-REPAIR INSPECTION
a) OPTION 4: Repeat PART 3: STATION 2370 PIVOT BULKHEAD FORWARD
CHORD - POST-REPAIR DET AND HFEC INSPECTION.
b) OPTION 2: Do the terminating modification in accordance with Boeing
Service Bulletin 777-53-0076.
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2) CONDITION 5: ANY FORWARD CHORD CRACK IS FOUND DURING
POST-REPAIR INSPECTION
a) Do the terminating modification in accordance with Boeing Service Bulletin
777-53-0076.
c. CONDITION 3: ANY FORWARD CHORD CRACK FOUND IS GREATER THAN 0.160 INCH
(1) Do the terminating modification in accordance with Boeing Service Bulletin 777-53-0076.
3. If not previously installed, install the skin panels in accordance with the figures below:
Right SideLeft Side
FIGURE 6FIGURE 5
4. Put the airplane back to a serviceable condition.
PART 1: STATION 2370 PIVOT BULKHEAD FORWARD CHORD - DET AND HFEC INSPECTION
1. RC - Do an inspection of the Pivot Bulkhead Forward Outer Chord, for any crack, in accordance
with the figures below:
Right SideLeft Side
FIGURE 4FIGURE 3
PART 2: STATION 2370 PIVOT BULKHEAD FORWARD CHORD - SMALL CRACK REPAIR
1. Support the airplane using one of the options below:
OPTION 1:
a. Support the airplane on its landing gear.
b. Remove the load from the pivot pin assembly on the side of the airplane where the small crack
repair is done. Refer to 777 AMM 55-17-01 as an accepted procedure. Removal of the pivot
pin assembly or pivot fitting bearing is not necessary. If the small crack repair is done on the
left and right side of the airplane at the same time, make sure that the pivot pin assemblies
are unloaded on the left and right side of the airplane at the same time.
OPTION 2:
a. Lift the airplane on the primary jacks A, B and C. Refer to 777 AMM 07-11-01 as an accepted
procedure.
b. Remove the load from the pivot pin assembly on the side of the airplane where the small crack
repair is done. Refer to 777 AMM 55-17-01 as an accepted procedure. Removal of the pivot
pin assembly or pivot fitting bearing is not necessary. If the small crack repair is done on the
left and right side of the airplane at the same time, make sure that the pivot pin assemblies
are unloaded on the left and right side of the airplane at the same time.
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2. Group 1:
Get access to the repair area in accordance with the figures below:
Right SideLeft Side
FIGURE 8FIGURE 7
3. Group 2:
Get access to the repair area in accordance with the figures below:
Right SideLeft Side
FIGURE 10FIGURE 9
4. RC - Do PART 4: STATION 2370 PIVOT BULKHEAD FORWARD CHORD AND ADJACENT
STRUCTURE - HFEC AND DET INSPECTION, for any crack.
a. CONDITION 6: NO FORWARD CHORD UPPER LOCATION OR ADJACENT STRUCTURE
CRACK IS FOUND
(1) RC - Continue to do the small crack repair in accordance with PART 2: STATION 2370
PIVOT BULKHEAD FORWARD CHORD - SMALL CRACK REPAIR.
b. CONDITION 7: ANY FORWARD CHORD UPPER LOCATION OR ADJACENT STRUCTURE
CRACK IS FOUND
(1) RC - ACTION 1: Contact The Boeing Company for repair instructions and do the repair.
(2) RC - ACTION 2: Continue to do the small crack repair in accordance with PART 2:
STATION 2370 PIVOT BULKHEAD FORWARD CHORD - SMALL CRACK REPAIR.
5. Group 1:
RC - Modify the splice angle in accordance with the figures below:
Right SideLeft Side
FIGURE 14FIGURE 13
6. Group 1:
RC - Repair the Station 2370 pivot bulkhead forward chord in accordance with the figures below:
Right SideLeft Side
FIGURE 16FIGURE 15
7. Group 2:
RC - Repair the Station 2370 pivot bulkhead forward chord in accordance with the figures below:
Right SideLeft Side
FIGURE 18FIGURE 17
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8. RC - Install the skin panels in accordance with the figures below:
Right SideLeft Side
FIGURE 24FIGURE 23
9. Apply finish to the repaired area to match adjacent structure. Apply BMS 3-23 (BMS 3-29 and
BMS 3-35 optional) corrosion inhibiting compound to the repaired area. Refer to SOPM 20-41-05
as an accepted procedure.
10. If the airplane was stabilized using OPTION 1, remove the horizontal stabilizer jacking equipment.
Refer to 777 AMM 55-17-01 as an accepted procedure.
11. If the airplane was stabilized using OPTION 2,
a. Remove the horizontal stabilizer jacking equipment. Refer to 777 AMM 55-17-01 as an accepted
procedure.
b. Lower the airplane off of the jacks. Refer to 777 AMM 07-11-01 as an accepted procedure.
PART 3: STATION 2370 PIVOT BULKHEAD FORWARD CHORD - POST-REPAIR DET AND HFEC
INSPECTION
1. Remove the skin panels in accordance with the figures below:
Right SideLeft Side
FIGURE 26FIGURE 25
2. RC - Do the DET and HFEC inspection in accordance with the figures below:
Right SideLeft Side
FIGURE 20FIGURE 19
3. RC - Install the skin panels in accordance with the figures below:
Right SideLeft Side
FIGURE 22FIGURE 21
4. Put the airplane back to a serviceable condition.
PART 4: STATION 2370 PIVOT BULKHEAD FORWARD CHORD AND ADJACENT STRUCTURE
- HFEC AND DET INSPECTION
1. RC - Inspect the pivot bulkhead forward chord and adjacent structure in accordance with the figures
below:
Right SideLeft Side
FIGURE 12FIGURE 11
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### Page 43 (OCR)

BOEING SERVICE BULLETIN 777-53A0075
ALERT  ALERT
STA
2370
SPLICI
2) PLATI
FILLER
FILLER g
SKIN E
BRACKET 2)  FILLER
ANGLE  FILLER 2
(2) SKIN
FIGURE 1: LEFT SIDE - STA 2370 SKIN PANEL REMOVAL
(SHEET 1 OF 4)
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### Page 44 (OCR)

BOEING SERVICE BULLETIN 777-53A0075
ALERT  ALERT
STA
2370
STA
2362.75
12 LOCATIONS
10 LOCATIONS (
FWD
A-A  2356615
FIGURE 1: LEFT SIDE - STA 2370 SKIN PANEL REMOVAL
(SHEET 2 OF 4)
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### Page 45 (OCR)

BOEING SERVICE BULLETIN 777-53A0075
ALERT  ALERT
_ GUSSET
- BRACKET  1 BRACKET
3 SPLICE PLATE
SKIN
FWD
B-B
ANGLE 2  CHORD.
3 BRACKET
© FILLER
1 SKIN
FWD
TYPICAL
C-C  2356494
FIGURE 1: LEFT SIDE - STA 2370 SKIN PANEL REMOVAL
(SHEET 3 OF 4)
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### Page 46

The step numbers shown below agree with the numbers shown in the circle symbols in the figure. The QTY
numbers shown below are the number of parts necessary for this figure.
More DataQtyIdentificationNameTaskStep
24-FASTENERRemove1
3-FASTENERRemove/Keep2
1148W2912-1SKIN
1148W2912-3SKIN
1148W2917-9FILLER
1148W2917-11FILLER
1148W2917-7FILLER
1148W2914-( )ANGLE - FAIRING
ASSY, UPPER
1BACF3T03M14S8BFILLER
1148W2918-3SPLICE PLATE
1148W2920-1BRACKET
FIGURE 1: LEFT SIDE - STA 2370 SKIN PANEL REMOVAL
(SHEET 4 OF 4)
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### Page 47 (OCR)

BOEING SERVICE BULLETIN 777-53A0075
ALERT  ALERT
STA
2370
SPLIC
≥ PLAT
2 FILLER
2 FILLER
2 SKIN
FILLER  2) BRACKET
SKIN 2  I FILLER  ANGLE  2357492
FIGURE 2: RIGHT SIDE - STA 2370 SKIN PANEL REMOVAL
(SHEET 1 OF 4)
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### Page 48 (OCR)

BOEING SERVICE BULLETIN 777-53A0075
ALERT  ALERT
STA
2370
STA
2362.75
12 LOCATIONS
10 LOCATIONS
FWD
A-A  2357535
FIGURE 2: RIGHT SIDE - STA 2370 SKIN PANEL REMOVAL
(SHEET 2 OF 4)
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### Page 49 (OCR)

BOEING SERVICE BULLETIN 777-53A0075
ALERT  ALERT
GUSSET-
BRACKET 2  BRACKET -
SPLICE PLATE 3
SKIN
FWD
B-B
CHORD  2 ANGLE
BRACKET 3
SKIN e  FILLER 2
FWD
TYPICAL
C-C
2357551
FIGURE 2: RIGHT SIDE - STA 2370 SKIN PANEL REMOVAL
(SHEET 3 OF 4)
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### Page 50

The step numbers shown below agree with the numbers shown in the circle symbols in the figure. The QTY
numbers shown below are the number of parts necessary for this figure.
More DataQtyIdentificationNameTaskStep
24-FASTENERRemove1
3-FASTENERRemove/Keep2
1148W2912-2SKIN
1148W2912-4SKIN
1148W2917-9FILLER
1148W2917-11FILLER
1148W2917-7FILLER
1148W2914-( )ANGLE - FAIRING
ASSY, UPPER
1BACF3T03M14S8BFILLER
1148W2918-4SPLICE PLATE
1148W2920-2BRACKET
FIGURE 2: RIGHT SIDE - STA 2370 SKIN PANEL REMOVAL
(SHEET 4 OF 4)
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BOEING SERVICE BULLETIN 777-53A0075
ALERT  ALERT
STA
2370
B
* B  S-17L
2385532
FIGURE 3: LEFT SIDE - STA 2370 PIVOT BULKHEAD FORWARD OUTER CHORD - DET AND HFEC
INSPECTION
(SHEET 1 OF 4)
Original Issue: January 14, 2015
Revision 1 December 14, 2015  Export Controlled ECCN: 9E991 - BOEING  777-53A0075
PROPRIETARY - Copyright © Unpublished
Work - See page 1 for details.  51 of 248

### Page 52 (OCR)

BOEING SERVICE BULLETIN 777-53A0075
ALERT  ALERT
CHORD
0.53
0.47.
0.53
STA
2362.75
INSPECTION  A-A  2358099
AREA
FIGURE 3: LEFT SIDE - STA 2370 PIVOT BULKHEAD FORWARD OUTER CHORD - DET AND HFEC
INSPECTION
(SHEET 2 OF 4)
Original Issue: January 14, 2015
Revision 1 December 14, 2015  PROPRIETARY - Copyright © Unpublished  Export Controlled ECCN: 9E991 - BOEING  777-53A0075
Work - See page 1 for details.  52 of 248

### Page 53

The step numbers shown below agree with the numbers shown in the circle symbols in the figure. The QTY
numbers shown below are the number of parts necessary for this figure.
More DataQtyIdentificationNameTaskStep
Do a DET for any crack.1148W7102-( )CHORD - FOR-
WARD, PIVOT
BULKHEAD, MID
Inspect1
FIGURE 3: LEFT SIDE - STA 2370 PIVOT BULKHEAD FORWARD OUTER CHORD - DET AND HFEC
INSPECTION
(SHEET 3 OF 4)
Export Controlled ECCN: 9E991 - BOEING
PROPRIETARY - Copyright © Unpublished
Work - See page 1 for details.
Original Issue: January 14, 2015
777-53A0075Revision 1 December 14, 2015
53 of 248
BOEING SERVICE BULLETIN 777-53A0075
ALERTALERT

### Page 54

More DataQtyIdentificationNameTaskStep
Do a DET for any crack.1148W7102-( )CHORD - FOR-
WARD, PIVOT
BULKHEAD, MID
Inspect2
Do an open hole HFEC inspection for
any crack, in accordance with 777 NDT
Manual Part 6, 51-00-02.
1148W7102-( )CHORD - FOR-
WARD, PIVOT
BULKHEAD, MID
Inspect3
Do a surface HFEC inspection for any
crack, in accordance with 777 NDT
Manual Part 6, 51-00-01.
1148W7102-( )CHORD - FOR-
WARD, PIVOT
BULKHEAD, MID
Inspect4
FIGURE 3: LEFT SIDE - STA 2370 PIVOT BULKHEAD FORWARD OUTER CHORD - DET AND HFEC
INSPECTION
(SHEET 4 OF 4)
Export Controlled ECCN: 9E991 - BOEING
PROPRIETARY - Copyright © Unpublished
Work - See page 1 for details.
Original Issue: January 14, 2015
777-53A0075Revision 1 December 14, 2015
54 of 248
BOEING SERVICE BULLETIN 777-53A0075
ALERTALERT

### Page 55 (OCR)

BOEING SERVICE BULLETIN 777-53A0075
ALERT  ALERT
STA
2370
S-17R  - 4\
<
2358103
FIGURE 4: RIGHT SIDE - STA 2370 PIVOT BULKHEAD FORWARD OUTER CHORD - DET AND HFEC
INSPECTION
(SHEET 1 OF 4)
Original Issue: January 14, 2015
Revision 1 December 14, 2015  Export Controlled ECCN: 9E991 - BOEING  777-53A0075
PROPRIETARY - Copyright © Unpublished
Work - See page 1 for details.  55 of 248

### Page 56 (OCR)

BOEING SERVICE BULLETIN 777-53A0075
ALERT  ALERT
CHORD.
STA
2370  0.53
0.47  STA
2362.75
FWD  INSPECTION
A-A  AREA  2358104
FIGURE 4: RIGHT SIDE - STA 2370 PIVOT BULKHEAD FORWARD OUTER CHORD - DET AND HFEC
INSPECTION
(SHEET 2 OF 4)
Original Issue: January 14, 2015
Revision 1 December 14, 2015  PROPRIETARY - Copyright © Unpublished  Export Controlled ECCN: 9E991 - BOEING  777-53A0075
Work - See page 1 for details.  56 of 248

### Page 57

The step numbers shown below agree with the numbers shown in the circle symbols in the figure. The QTY
numbers shown below are the number of parts necessary for this figure.
More DataQtyIdentificationNameTaskStep
Do a DET for any crack.1148W7102-( )CHORD - FOR-
WARD, PIVOT
BULKHEAD, MID
Inspect1
FIGURE 4: RIGHT SIDE - STA 2370 PIVOT BULKHEAD FORWARD OUTER CHORD - DET AND HFEC
INSPECTION
(SHEET 3 OF 4)
Export Controlled ECCN: 9E991 - BOEING
PROPRIETARY - Copyright © Unpublished
Work - See page 1 for details.
Original Issue: January 14, 2015
777-53A0075Revision 1 December 14, 2015
57 of 248
BOEING SERVICE BULLETIN 777-53A0075
ALERTALERT

### Page 58

More DataQtyIdentificationNameTaskStep
Do a DET for any crack.1148W7102-( )CHORD - FOR-
WARD, PIVOT
BULKHEAD, MID
Inspect2
Do an open hole HFEC inspection for
any crack, in accordance with 777 NDT
Manual Part 6, 51-00-02.
1148W7102-( )CHORD - FOR-
WARD, PIVOT
BULKHEAD, MID
Inspect3
Do a surface HFEC inspection for any
crack, in accordance with 777 NDT
Manual Part 6, 51-00-01.
1148W7102-( )CHORD - FOR-
WARD, PIVOT
BULKHEAD, MID
Inspect4
FIGURE 4: RIGHT SIDE - STA 2370 PIVOT BULKHEAD FORWARD OUTER CHORD - DET AND HFEC
INSPECTION
(SHEET 4 OF 4)
Export Controlled ECCN: 9E991 - BOEING
PROPRIETARY - Copyright © Unpublished
Work - See page 1 for details.
Original Issue: January 14, 2015
777-53A0075Revision 1 December 14, 2015
58 of 248
BOEING SERVICE BULLETIN 777-53A0075
ALERTALERT

### Page 59 (OCR)

BOEING SERVICE BULLETIN 777-53A0075
ALERT  ALERT
STA
2370
SPLICE PLATE
FILLER
FILLER
SKIN
BRACKET
ANGLE  FILLER  SKIN OE3
FIGURE 5: LEFT SIDE - STA 2370 SKIN PANEL INSTALLATION
(SHEET 1 OF 5)
Original Issue: January 14, 2015
Revision 1 December 14, 2015  PROPRIETARY - Copyright © Unpublished  Export Controlled ECCN: 9E991 - BOEING  777-53A0075
Work - See page 1 for details.  59 of 248

### Page 60 (OCR)

BOEING SERVICE BULLETIN 777-53A0075
ALERT  ALERT
STA
2370
STA
2362.75
- •  103
10 LOCATIONS A  12 LOCATIONS  1eC
FWD
A-A  2384250
FIGURE 5: LEFT SIDE - STA 2370 SKIN PANEL INSTALLATION
(SHEET 2 OF 5)
Original Issue: January 14, 2015
Revision 1 December 14, 2015  PROPRIETARY - Copyright © Unpublished  Export Controlled ECCN: 9E991 - BOEING  777-53A0075
Work - See page 1 for details.  60 of 248

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