# Boeing Service Bulletin A3365: Revision 3

- Rights: © The Boeing Company. Filed by the FAA in regulations.gov docket FAA-2018-0504; AD 2018-19-32 incorporates this document by reference. Not covered by OpenAirDocs’ CC0 dedication.
- Document: [Boeing Service Bulletin A3365](https://openairdocs.org/service-documents/boeing/a3365.md)
- Title as filed: SB-707-00A3365-03--
- Pages: 37
- PDF: https://openairdocs.org/files/sha256/77/f3/77f33a8a2d7869502bf52c4de7fd417b66511f0bb86a537131a5c9e240ce000f
- Page: https://openairdocs.org/service-documents/boeing/a3365/file/77f33a8a2d78

## Text

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### Page 1

Commercial 
Airplanes
707
Service Bulletin
ALERT
Number: A3365
Original Issue: August 17, 1979
Revision 3: March 09, 2017
ATA System: 5700 5401
SUBJECT: WINGS - INBOARD AND OUTBOARD NACELLE STRUT OVERWING SUPPORT
FITTING INSPECTION AND REPAIR AT WING FRONT SPAR
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 © 1989 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Unpublished Work.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: August 17, 1979
A3365Revision 3: March 09, 2017
1 of 37
2.0

### Page 2

Export Controlled ECCN: 9E991 - BOEING
PROPRIETARY - Copyright © Unpublished
Work - See page 1 for details.
Original Issue: August 17, 1979
A3365Revision 3: March 09, 2017
2 of 37
BOEING SERVICE BULLETIN A3365
ALERTALERT
BLANK PAGE

### Page 3

Table of Contents
Revision Transmittal Sheet . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
1. PLANNING INFORMATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
A. Effectivity . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
1. Airplanes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
2. Spares Affected . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
B. Concurrent Requirements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
C. Reason . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
D. Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18
E. Compliance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19
F. Approval . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24
G. Manpower . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24
H. Weight and Balance Changes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25
I. Electrical Load Data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25
J. References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25
1. Existing Data: . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25
2. Data Supplied with this Service Bulletin: . . . . . . . . . . . . . . . . . . . . . . . . . . . 26
3. Installation Drawings Used in the Preparation of this Service Bulletin: . . . . . . . . . . . 26
K. Publications Affected . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26
L. Interchangeability and Intermixability of Parts . . . . . . . . . . . . . . . . . . . . . . . . . . . 26
M. Software Accomplishment Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26
2. MATERIAL INFORMATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27
A. Material - Price and Availability . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27
B. Industry Support Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27
C. Parts Necessary for Each Airplane . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27
1. Kits/Parts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27
2. Parts and Materials Supplied by the Operator . . . . . . . . . . . . . . . . . . . . . . . . 27
3. Parts Modified and Reidentified . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28
4. Parts Removed and Not Replaced . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28
D. Parts Necessary to Change Spares . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28
E. Special Tooling - Price and Availability . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28
F. Special Tooling Necessary to do this Service Bulletin . . . . . . . . . . . . . . . . . . . . . . . 28
3. ACCOMPLISHMENT INSTRUCTIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29
A. GENERAL INFORMATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29
B. WORK INSTRUCTIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30
FIGURE 1: OVERWING SUPPORT FITTING INSPECTION . . . . . . . . . . . . . . . . . . . . . . . 32
FIGURE 2: OVERWING SUPPORT FITTING REPLACEMENT FASTENERS AND OPTIONAL COLD WORK
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35
Export Controlled ECCN: 9E991 - BOEING
PROPRIETARY - Copyright © Unpublished
Work - See page 1 for details.
Original Issue: August 17, 1979
A3365Revision 3: March 09, 2017
3 of 37
BOEING SERVICE BULLETIN A3365
ALERTALERT

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Export Controlled ECCN: 9E991 - BOEING
PROPRIETARY - Copyright © Unpublished
Work - See page 1 for details.
Original Issue: August 17, 1979
A3365Revision 3: March 09, 2017
4 of 37
BOEING SERVICE BULLETIN A3365
ALERTALERT
BLANK PAGE

### Page 5

Commercial 
Airplanes
707
Service Bulletin
ALERT
Revision Transmittal SheetNumber: A3365Original Issue: August 17, 1979
Revision 3: March 09, 2017
ATA System: 5700 5401
SUBJECT: WINGS - INBOARD AND OUTBOARD NACELLE STRUT OVERWING SUPPORT
FITTING INSPECTION AND REPAIR AT WING FRONT SPAR
This revision includes all pages of the service bulletin.
COMPLIANCE INFORMATION RELATED TO THIS REVISION
The Federal Aviation Administration (FAA) will possibly release an Airworthiness Directive related to this service
bulletin. The Airworthiness Directive will make the compliance tasks and times given in this service bulletin
mandatory.
Effects of this Revision on airplanes on which Original Issue, Revision 1 or Revision 2 was previously done:
None.
REASON FOR REVISION
This revision is sent to change the inspection interval for detailed inspections, High Frequency Eddy Current
(HFEC) inspections and ultrasonic inspection and to add alternative HFEC inspections around the aft bolts. The
option to repair parts by oversizing the holes has been removed.
The data given in Notice of Status Change 707-3365 NSC 1 is included in this revision.
Terminology has been changed in the Work Instructions to agree with the terminology defined in Paragraph
3.A., General Information - Notes.
These sections were changed:
1. Summary, Concurrent Requirements: Added this section.
2. Summary, Background: Added paragraph, added references to Service Related Problem (SRP) and
Fleet Team Digest (FTD).
3. Summary, Action: Revised paragraph.
4. Summary, Effectivity: Added reference to Paragraph 1.A.1., Airplanes.
5. Summary, Compliance: Added this section and added AD statement and reference to Paragraph 1.E.,
Compliance.
Export Controlled ECCN: 9E991 - BOEING
PROPRIETARY - Copyright © Unpublished
Work - See page 1 for details.
Original Issue: August 17, 1979
A3365Revision 3: March 09, 2017
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### Page 6

6. Summary, Industry Support Information: Added this section and warranty statement.
7. Summary, Manpower: Removed table and added reference to Paragraph 1.G., Manpower.
8. Summary, Material Information: Added this section and added operator supplied parts/materials
statement and reference to Paragraph 2.A., Material - Price and Availability.
9. Summary, Illustration: Revised text.
10. Paragraph 1.A.1., Airplanes: Updated the format of the effectivity.
11. Paragraph 1.B., Concurrent Requirements: Added this section.
12. Paragraph 1.C., Reason: Revised text and added revision 2 and revision 3 statements.
13. Paragraph 1.D., Description: Revised paragraphs and added extra work statement and table.
14. Paragraph 1.E., Compliance: Added this section and Compliance Table, and added AD, compliance
and accomplishment statements.
15. Paragraph 1.G., Manpower: Added task hour statement and revised table format.
16. Paragraph 1.I., Electrical Load Data: Added this section and statement.
17. Paragraph 1.J.1., Existing Data. Updated paragraph to incorporate added references.
18. Paragraph 1.J.2., Data Supplied with this Service Bulletin: Added this paragraph and statement (no
vertical line shown for this change).
19. Paragraph 1.J.3., Illustration Drawings used in the Preparation of this Service Bulletin: Added this
paragraph and statement.
20. Paragraph 1.K.2., Damage Tolerance Based Structural Inspections: Added this paragraph and statement.
21. Paragraph 1.L., Interchangeability and Intermixability of Parts: Added this section and statement.
22. Paragraph 1.M., Software Accomplishment Summary: Added this section and statement.
23. Paragraph 2. Material Information: Removed: Parts Required Per Airplane, Parts Required to Modify
Spares, Special Tools and Equipment Required and Existing Parts Accountability.
24. Paragraph 2. Material Information: Added : 2.A., Material - Price and Availability, and text; 2.B., Industry
Support Information, and text; 2.C., Parts Necessary or each Airplane; 2.C.1., Kits/Parts, and text;
2.C.2., Parts and Materials Supplied by Operator, and text; 2.C.3., Parts Modified and Reidentified,
and text; 2.C.4., Parts Removed and Not Replaced, and text; 2.D., Parts Necessary to Change Spares,
and text; 2.E., Special Tooling - Price and Availability, and text; 2.F., Special Tooling Necessary to do
this Service Bulletin, and text.
25. Paragraph 3. Accomplishment Instructions: Added Paragraph 3.A., General Information and text, and
added Paragraph 3.B., Work Instructions with revised text.
26. Figure 1: Revised and added extra view on illustration and revised circle numbers. Revised circle notes
and added material identification inspection, NDT references, and an alternative HFEC inspection.
Export Controlled ECCN: 9E991 - BOEING
PROPRIETARY - Copyright © Unpublished
Work - See page 1 for details.
Original Issue: August 17, 1979
A3365Revision 3: March 09, 2017
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BOEING SERVICE BULLETIN A3365
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### Page 7

27. Figure 2: Revised illustration and circle numbers. Removed and revised notes, added optional cold
working of holes, SOPM references, HFEC procedure, and added instruction to increase hole size if
no is crack found. Replaced bolt part number.
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
August 17, 1979Original Issue:
November 30, 1979Revision 1:
January 31, 1991Revision 2:
March 09, 2017Revision 3:
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PROPRIETARY - Copyright © Unpublished
Work - See page 1 for details.
Original Issue: August 17, 1979
A3365Revision 3: March 09, 2017
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BOEING SERVICE BULLETIN A3365
ALERTALERT

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Export Controlled ECCN: 9E991 - BOEING
PROPRIETARY - Copyright © Unpublished
Work - See page 1 for details.
Original Issue: August 17, 1979
A3365Revision 3: March 09, 2017
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BOEING SERVICE BULLETIN A3365
ALERTALERT
BLANK PAGE

### Page 9

Commercial 
Airplanes
707
Service Bulletin
ALERT
SummaryNumber: A3365Original Issue: August 17, 1979
Revision 3: March 09, 2017
ATA System: 5700 5401
SUBJECT: WINGS - INBOARD AND OUTBOARD NACELLE STRUT OVERWING SUPPORT
FITTING INSPECTION AND REPAIR AT WING FRONT SPAR
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
None.
BACKGROUND
Fatigue cracks have been reported in the overwing support fitting on eight airplanes with 26,000 to 55,300
flight-hours (9,600 to 27,200 flights). Four fittings had cracks at the fastener holes for attachment to the wing
front spar upper chord horizontal flange. Four were cracked at the bolt hole immediately forward of the spar
chord.
The inboard and outboard nacelle struts are also supported by the more critical midspar fittings which are
inspected and replaced if required in service bulletin 707A3183 Revision 6. Service bulletin 707A3183 Revision
6 has been created to address the fracture of the midspar fitting that resulted in the separation of the inboard
strut and engine from the airplane. Service bulletin 707A3183 Revision 6 has new detailed inspections and High
Frequency Eddy Current (HFEC) inspections. Existing service and regulatory actions for other nacelle strut
fittings, including the overwing support fitting, are not sufficient for in-time detection of any crack which could
lead to separation of an engine. As a result, service bulletin 707A3365 Revision 3 has been created to increase
the frequency of the detailed, HFEC and ultrasonic inspections of the overwing support fitting, in alignment with
inspections for the midspar fittings.
Boeing Service Related Problem (SRP) 707-54-0155 is related to this service bulletin.
Boeing Fleet Team Digest (FTD) 707 FTD 54-05001 is related to this service bulletin.
Export Controlled ECCN: 9E991 - BOEING
PROPRIETARY - Copyright © Unpublished
Work - See page 1 for details.
Original Issue: August 17, 1979
A3365Revision 3: March 09, 2017
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### Page 10

ACTION
Inspect the overwing support fittings for any crack at the bolt hole forward of the wing front spar and at the holes
for the four fasteners attaching the fitting to the spar. At the forward hole, inspection must be made with a detailed
inspection, and with either a surface High Frequency Eddy Current (HFEC) inspection or an open hole HFEC
inspection. At the four aft holes, inspection must be made with a detailed inspection and either a surface HFEC
inspection or ultrasonically. Any crack may be repaired by contacting The Boeing Company for repair instructions
and doing the repair, or by replacing the part. Repeat inspections in accordance with this service bulletin.
EFFECTIVITY
All 707 and 720 Airplanes. Refer to Paragraph 1.A.1., Airplanes, for the list of affected airplanes.
COMPLIANCE
The Federal Aviation Administration (FAA) will possibly release an Airworthiness Directive related to this service
bulletin. The Airworthiness Directive will make the compliance tasks and times given in this service bulletin
mandatory.
Refer to Paragraph 1.E., Compliance.
INDUSTRY SUPPORT INFORMATION
Boeing warranty remedies are not available for the inspection,and/or repair procedures given in this service
bulletin.
MANPOWER
Refer to Paragraph 1.G., Manpower.
MATERIAL INFORMATION
Operator Supplied Parts/Materials.
Refer to Paragraph 2.A., Material - Price and Availability.
Export Controlled ECCN: 9E991 - BOEING
PROPRIETARY - Copyright © Unpublished
Work - See page 1 for details.
Original Issue: August 17, 1979
A3365Revision 3: March 09, 2017
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BOEING SERVICE BULLETIN A3365
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### Page 11 (OCR)

BOEING SERVICE BULLETIN A3365
ALERT  ALERT
INBOARD NACELLE
OUTBOARD NACELLE.
DO A DETAILED INSPECTION
AND HIGH FREQUENCY EDDY
NACELLE STRUT  CURRENT (HFEC) INSPECTION
FWD
DO A DETAILED
INSPECTION AND DO
HFEC OR ULTRASONIC
INSPECTION
WING FRONT SPAR  UPPER CHORD  2539985
Original Issue: August 17, 1979
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PROPRIETARY - Copyright © Unpublished  Work - See page 1 for details.  11 of 37

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Export Controlled ECCN: 9E991 - BOEING
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Original Issue: August 17, 1979
A3365Revision 3: March 09, 2017
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ALERTALERT
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### Page 13

Commercial 
Airplanes
707
Service Bulletin
ALERT
Number: A3365
Original Issue: August 17, 1979
Revision 3: March 09, 2017
ATA System: 5700 5401
SUBJECT: WINGS - INBOARD AND OUTBOARD NACELLE STRUT OVERWING SUPPORT
FITTING INSPECTION AND REPAIR AT WING FRONT SPAR
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.
1.    PLANNING INFORMATION
A. Effectivity
1. Airplanes
This service bulletin is applicable to all 707 and 720 Airplanes, in 1 Group. The Variable Numbers
and Group Information for the applicable airplanes is given below.
Refer to Service Bulletin Index D6-1647 Part 3 for Airplane Variable Number, Line Number, and
Serial Number data.
DESCRIPTIONCONFIGURATIONGROUP
All 707-100 Long Body, 707-100B Long Body, 707-100B Short Body,
707-200, 707-300, 707-300B, 707-300C, 707-400, 720 and 720B
Airplanes.
-1
Airplane Models:
707-100 LONG BODY, 707-100B LONG BODY, 707-100B SHORT BODY, 707-200, 707-300,
707-300B, 707-300C, 707-400, 720, 720B
GroupVariable Number
1B0001 - B0029
1B0101 - B0125
1B0201 - B0203
1B0301 - B0306
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### Page 14

GroupVariable Number
1B0401 - B0402
1B0501 - B0515
1B2001 - B2008
1B2091 - B2092
1B2101 - B2116
1B2191 - B2194
1B2199
1B2201 - B2227
1B2401 - B2403
1B2501 - B2502
1B2551 - B2553
1B2601 - B2608
100001 - 00002
100004 - 00006
100101
100103 - 00113
100115 - 00153
100201 - 00205
100301 - 00305
100401 - 00449
100471 - 00475
100501 - 00513
100601
100701 - 00703
102001 - 02020
102101 - 02121
102201 - 02207
102301 - 02303
102401 - 02418
104001 - 04005
104020 - 04022
104101 - 04106
104201 - 04218
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GroupVariable Number
104271 - 04272
104301 - 04303
105001 - 05060
105101 - 05138
105201 - 05208
105301 - 05312
105401
105601 - 05605
105631 - 05635
105701 - 05703
105801 - 05802
105821 - 05827
105831 - 05833
105851 - 05854
105891 - 05892
105921 - 05923
105941 - 05942
105961 - 05970
106001 - 06002
106101
106401 - 06404
106451
106461
107001 - 07017
107041 - 07059
107071 - 07081
107101 - 07109
107181
107191
107201 - 07215
107251 - 07271
107401 - 07407
107451 - 07458
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GroupVariable Number
107501 - 07504
107601 - 07626
107661 - 07662
107681 - 07684
107701 - 07702
107801 - 07821
107901 - 07907
108001 - 08008
108021
108051 - 08056
108071 - 08077
108101 - 08104
108121 - 08129
108141 - 08144
108151 - 08153
108171 - 08173
108191 - 08192
108201 - 08210
108221 - 08224
108241 - 08244
108251
108261
108271
108301 - 08320
108324 - 08330
108333
108401 - 08410
108451 - 08452
108471 - 08475
108501 - 08502
108551 - 08553
108581 - 08582
109001 - 09006
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GroupVariable Number
109101 - 09107
109161 - 09167
109201 - 09204
109221 - 09223
109227
109231 - 09232
109251
109271
109281
109286 - 09290
109411
109421
109438
109441
2. Spares Affected
None.
B. Concurrent Requirements
None.
C. Reason
Periodic inspection at the five holes in the inboard and outboard nacelle strut overwing support fitting
at the wing front spar may detect any crack. Any crack found requires contacting The Boeing Company
for repair instructions and doing the repair, or fitting replacement.
Seven operators have reported fitting cracks on eight airplanes that had accumulated 26,500 to 55,300
flight-hours (9,600 to 27,200 flight cycles). Seven of the fittings were at the inboard strut and one at
the outboard strut. Four of the cracks initiated in the holes for the fasteners through the fitting and the
wing front spar upper chord horizontal flange. Four initiated in the hole for bolt through the fitting and
a bracket on the forward face of the chord vertical flange. One of the four fittings was completely
severed, two cracked halfway through and the crack in the fourth fitting was removed by oversizing
the hole.
Continued operation with a cracked overwing support fitting could eventually affect the structural integrity
of the remaining nacelle strut attachments to the wing.
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### Page 18

The inboard and outboard nacelle struts are also supported by the more critical midspar fittings which
are inspected and replaced if required in service bulletin 707A3183 Revision 6. Service bulletin 707A3183
Revision 6 has been created to address the fracture of the midspar fitting that resulted in the separation
of the inboard strut and engine from the airplane. Service bulletin 707A3183 Revision 6 has new detailed
inspections and High Frequency Eddy Current (HFEC) inspections with a mid-interval compliance time
of 1500 flight cycles or 48 months, whichever comes first. Existing service and regulatory actions for
other nacelle strut fittings, including the overwing support fitting, are not sufficient to make sure of
in-time detection of any crack which could lead to separation of an engine. As a result, service bulletin
707A3365 Revision 3 has been created to increase the frequency of the detailed, HFEC and ultrasonic
inspections of the overwing support fitting, in alignment with inspections for the midspar fittings.
Boeing Service Related Problem (SRP) 707-54-0155 is related to this service bulletin.
Boeing Fleet Team Digest (FTD) 707 FTD 54-05001 is related to this service bulletin.
Revision 1 of this bulletin was issued to advise repeat inspections of the overwing fittings in addition
to the one-time inspection advised in the original issue of the bulletin.
Revision 2 of this bulletin was sent to add optional low interference cold working of the overwing support
fitting holes. Master service bulletins 707-3478, 707-3479 and 707-3480 define these revisions to
service bulletin 707-3365 Revision 1.
Revision 3 of this bulletin is sent to change the inspection interval for detailed inspections, High
Frequency Eddy Current (HFEC) inspections and ultrasonic inspection and to add alternative HFEC
inspections around the aft bolts. The option to repair parts by oversizing the holes has been removed.
The data given in Notice of Status Change (NSC) 707-3365 NSC 1 is included in this revision.
D. Description
On nacelle strut overwing support fittings, do repeat inspections for any crack at the five affected
fastener holes at the wing front spar upper chord.
Detailed Inspection must be made at all five holes. The hole immediately forward of the spar chord
must be inspected with a surface High Frequency Eddy Current (HFEC) inspection with the bolt in
place, or with an open hole HFEC inspection with the bolt removed. If the hole is bushed as a result
of crack removal oversizing, remove bushing, do a detailed inspection, and either inspect hole with an
open hole HFEC inspection or accomplish the surface HFEC inspection. If any crack is found, do an
open hole HFEC inspection at the other four hole locations for any crack in the overwing support fitting,
wing skin, chord and support bracket fastener holes.
At the holes for the four fasteners attaching the overwing support fitting to the spar upper chord, the
fitting must be inspected either ultrasonically or with a surface HFEC inspection in addition to the
detailed inspection. If any crack is found ultrasonically or with a surface HFEC inspection, remove the
fastener and do an open hole HFEC inspection.
If any crack is found in any part, repair the cracked part by contacting The Boeing Company for repair
instructions, and do the repair, or replace the cracked part.
Effects of this Revision on airplanes on which Original Issue, Revision 1 or Revision 2 was previously
done:
None.
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NOTE:
An inboard or outboard nacelle strut overwing support fitting may have been replaced
per Service Bulletin 707-1798 or 707-2090. An inboard fitting may have been replaced
per service bulletin 707-3173.
1.
2. Service Bulletin 707A3183 advises inspection at the inboard overwing fitting-to-wing
front spar upper chord horizontal flange fasteners if any crack is found in the nacelle
strut mid spar fittings. The inspections in this Service Bulletin 707A3365 Revision 3
do not supersede the inspections in service bulletin 707A3183.
3. Concurrent incorporation of Service Bulletins 707-3173, 707A3183, 707A3514 and
707A3364 is suggested on commonly affected airplanes, if not already incorporated,
in the interest of man-hour and airplane down-time savings.
4. Please notify Boeing of inspection results and your planned action.
The work in this service bulletin is done in the maintenance zone(s) given below.
Affected Maintenance Zones
ZoneModel
4-55, 4-56, 4-57, 4-58707-100 LONG BODY, 707-
100B LONG BODY, 707-100B
SHORT BODY, 707-200, 707-
300, 707-300B, 707-300C, 707-
400, 720, 720B
E. Compliance
The Federal Aviation Administration (FAA) will possibly release an Airworthiness Directive related to
this service bulletin. The Airworthiness Directive will make the compliance tasks and times given in this
service bulletin mandatory.
Accomplish the required actions, based on the applicable conditions in Table 1, 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.
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Table 1: Inspections of the Overwing Support Fitting for Any Crack at Nacelle Struts, Numbers 1, 2, 3
and 4
Repeat Inter-
val (Not to Ex-
ceed)
Compliance Time (Whichever
Occurs First)
ActionCondition
-Within 48
months after the
Revision 3 date
of this service
bulletin.
Within 1500
flight cycles af-
ter the Revision
3 date of this
service bulletin.
Action 1: Do a detailed inspec-
tion for any crack at all five holes
in the overwing support fitting,
and at the flange radii.
All Airplanes
-Within 48
months after the
Revision 3 date
of this service
bulletin.
Within 1500
flight cycles af-
ter the Revision
3 date of this
service bulletin.
Action 2, (Option 1): Do a High
Frequency Eddy Current (HFEC)
surface inspection for any crack
in the overwing support fitting
around the hole immediately for-
ward of the spar chord, with the
bolt in place, and at the flange
radii.
Action 2, (Option 2): Do an
HFEC open hole inspection for
any crack in the overwing sup-
port fitting at the hole immediate-
ly forward of the spar chord.
-Within 48
months after the
Revision 3 date
of this service
bulletin.
Within 1500
flight cycles af-
ter the Revision
3 date of this
service bulletin.
Action 3, (Option 1): Do an ultra-
sonic inspection for any crack in
the overwing support fitting
around the four holes common
to the fitting and the spar chord,
with the bolts in place.
Action 3, (Option 2): Do an
HFEC surface inspection for any
crack in the overwing support
fitting around the four holes
common to the fitting and the
spar chord, with the bolts in
place.
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Table 1: Inspections of the Overwing Support Fitting for Any Crack at Nacelle Struts, Numbers 1, 2, 3
and 4
Repeat Inter-
val (Not to Ex-
ceed)
Compliance Time (Whichever
Occurs First)
ActionCondition
250 flight cy-
cles.
--Condition 1, Action 1: Repeat
detailed inspection for any crack
at all five holes in the overwing
support fitting, and at the flange
radii.
Condition 1: No crack
is found in the overwing
support fitting.
1500 flight cy-
cles or 48
months,
whichever oc-
curs first.
--Condition 1, Action 2, (Option 1):
Repeat HFEC surface inspection
for any crack in the overwing
support fitting around the hole
immediately forward of the spar
chord, with the bolt in place, and
at the flange radii.
Condition 1, Action 2, (Option 2):
Repeat HFEC open hole inspec-
tion for any crack in the overwing
support fitting at the hole imme-
diately forward of the spar chord.
1500 flight cy-
cles or 48
months,
whichever oc-
curs first.
--Condition 1, Action 3, (Option 1):
Repeat ultrasonic inspection for
any crack in the overwing sup-
port fitting around the four holes
common to the fitting and the
spar chord, with the bolts in
place.
Condition 1, Action 3, (Option 2):
Repeat HFEC surface inspection
for any crack in the overwing
support fitting around the four
holes common to the fitting and
the spar chord, with the bolts in
place.
--Before further
flight.
Remove the fastener at the hole
nearest to the crack, and do an
open hole HFEC inspection.
Condition 2: Any crack
is found in the overwing
support fitting during
the detailed, ultrasonic
or surface HFEC inspec-
tion.
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Table 1: Inspections of the Overwing Support Fitting for Any Crack at Nacelle Struts, Numbers 1, 2, 3
and 4
Repeat Inter-
val (Not to Ex-
ceed)
Compliance Time (Whichever
Occurs First)
ActionCondition
--Before further
flight.
Go to Condition 4 and do the
actions.
Condition 2.1: No other
crack is found after do-
ing the open hole
HFEC inspection at the
hole nearest to the
crack.
--Before further
flight.
Remove the remaining overwing
support fitting fasteners, and the
support bracket fasteners and
do an open hole HFEC inspec-
tion for any crack in the overwing
support fitting, wing skin, chord
and support bracket.
Condition 3: Any crack
is found during open
hole HFEC inspection
in any of the five holes
in the overwing support
fitting.
--Before further
flight.
Go to Condition 4 and do the
actions.
Condition 3.1: No other
crack is found after do-
ing the open hole
HFEC inspection at the
remaining holes in the
overwing support fitting,
wing skin, chord and
support bracket.
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Table 1: Inspections of the Overwing Support Fitting for Any Crack at Nacelle Struts, Numbers 1, 2, 3
and 4
Repeat Inter-
val (Not to Ex-
ceed)
Compliance Time (Whichever
Occurs First)
ActionCondition
--Before further
flight.
Condition 4, Action 1, (Option 1):
Contact The Boeing Company
for repair instructions and do the
repair.
Condition 4: Any crack
is found in the overwing
support fitting, wing
skin, chord or support
bracket. Condition 4, Action 1, (Option 2):
Replace the cracked part.
250 flight cy-
cles.
--Condition 4, Action 2: Repeat
detailed inspection for any crack
at all five holes in the overwing
support fitting, and at the flange
radii.
1500 flight cy-
cles or 48
months,
whichever oc-
curs first.
--Condition 4, Action 3, (Option 1):
Repeat HFEC surface inspection
for any crack in the overwing
support fitting around the hole
immediately forward of the spar
chord, with the bolt in place, and
at the flange radii.
Condition 4, Action 3, (Option 2):
Repeat HFEC open hole inspec-
tion for any crack in the overwing
support fitting at the hole imme-
diately forward of the spar chord.
1500 flight cy-
cles or 48
months,
whichever oc-
curs first.
--Condition 4, Action 4, (Option 1):
Repeat ultrasonic inspection for
any crack in the overwing sup-
port fitting around the four holes
common to the fitting and the
spar chord, with the bolts in
place.
Condition 4, Action 4, (Option 2):
Repeat HFEC surface inspection
for any crack in the overwing
support fitting around the four
holes common to the fitting and
the spar chord, with the bolts in
place.
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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.
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 shows an estimate of the task hours necessary to do this inspection and repair 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 - Inspection
Elapsed HoursTask HoursNumber of PersonsTask
284Open Access
(a)(a)(a)FIGURE 1
3124Close Access
(a)(a)TOTAL FOR EACH AIRPLANE
(a) Total time required may vary depending upon conditions found during inspec-
tions.
Table 2 - Fitting Repair (At One Location)
Elapsed HoursTask HoursNumber of PersonsTask
6366Open Access
(a)(a)(a)FIGURE 2
6366Close Access
881Fuel Leak Check
(a)(a)TOTAL FOR EACH LOCATION
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Table 2 - Fitting Repair (At One Location)
Elapsed HoursTask HoursNumber of PersonsTask
(a) Total time required may vary depending upon conditions found during inspec-
tions.
H. Weight and Balance Changes
None.
I. Electrical Load Data
Not applicable.
J. References
1. Existing Data:
a. Boeing Nondestructive Test Manual, 707/720 Airplanes, Part 4, 57-40-07, Figure 1 and Part
6, 51-00-00, Figures 4, 11, 16, 19, 20, 23 and 24
b. Service Bulletin 707-1798, "Nacelle Strut Upper Support Fitting Inspection and Bracket
Modification"
c. Service Bulletin 707-2090, "Nacelle Strut Upper Support Fitting Replacement"
d. Service Bulletin 707-3173, "Inboard Nacelle Strut Overwing Support Fitting Modification"
e. Service Bulletin 707A3183, "Inboard Nacelle Strut Midspar Fitting Inspection and Replacement"
f. Service Bulletin 707-3478, "Master Service Bulletin"
g. Service Bulletin 707-3479, "Master Service Bulletin"
h. Service Bulletin 707-3480, "Master Service Bulletin"
i. Service Bulletin 707A3364, "Nacelle Strut Diagonal Brace End Fitting Inspection and
Modification"
j. Service Bulletin 707A3514, "NACELLES - Nacelle Strut - Front Spar Fitting - Inspection and
Replacement"
k. 707 Aircraft Maintenance Manual (AMM) 12-2-0, 28-0, 71-5-0
l. 707-120 Structural Repair Manual (SRM) 51-2-5, 51-2-10, 51-2-11, 707-320 SRM 51-2-5,
51-2-10, 51-2-11 or 720 SRM 51-2-5, 51-2-10, 51-2-11
m. Standard Overhaul Practices Manual (SOPM) 20-50-01, 20-43-03
n. Boeing Service Letter 707-SL-51-029
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o. Boeing Service Related Problem (SRP) 707-54-0155
p. 707 Fleet Team Digest (FTD) 54-05001
2. Data Supplied with this Service Bulletin:
None.
3. Installation Drawings Used in the Preparation of this Service Bulletin:
None.
K. Publications Affected
1. Publications:
None.
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 but no new DTIs are necessary.
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
None.
B. Industry Support Information
Boeing warranty remedies are not available for the inspection and repair or replacement given in this
service bulletin.
C. Parts Necessary for Each Airplane
1. Kits/Parts
None.
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) (b)Bolt1BACB30US()P()
(a) (b)Bolt4BACB30MB()A()
(a) (b)Bolt2BACB30NF()-()
(a) (b)Bolt2BACB30FM()A()
(a) (b)Bolt2BACB30FN()A()
(a) (b)Nut1BACN10HR()
(a) (b)Nut2BACN10JC()CD
(a) (b)Collar4BACC30X()
(a) (b)Collar2BACC30M()
(b)Washer (Plain or Countersink)8BACW10BP()
(c) (b) (d)Primer8 ozBMS 10-11, Type I
(e) (f)Chemical Conversion Coating8 ozType 2, Class A
(a) Refer to 707 Structural Repair Manual Chapter 51 for alternate fasteners.
(b) QTY for each overwing support fitting.
(c) Refer to the Qualified Products List at the end of the Boeing Material Specification (BMS)
for supplier data.
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NotesNameQTYPart Number / Specification
(d) Some types of primer contain Strontium Chromate and will not be available in the European
Union (EU) after January 2019 without an authorization. EU operators are encouraged
to make sure their suppliers are authorized to provide this material after January 2019
and that users of this material comply with the risk mitigation measures and operational
conditions.
(e) Some types of Chemical Conversion Coating contain Chromium Trioxide Chromic Acid
and will not be available in the European Union (EU) after September 2017 without an
authorization. EU operators are encouraged to make sure their suppliers are authorized
to provide the material after September 2017 and that users of this material comply with
the risk mitigation measures and operational conditions.
(f) Refer to SOPM 20-43-03 for a list of materials and supplier data.
3. Parts Modified and Reidentified
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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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 707 Structural Repair Manual,
Chapter 51.
— Values for engine maintenance tasks are included in Chapter 70 of 707
Aircraft 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 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. 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.
8. Boeing Service Letter 707-SL-51-029, 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.
9. 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.
10. 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.
11. Use of colors in Figures is based on guidance from the ATA e-Business Program
(ATA) iSpec 2200.
12. The compliance times for the actions in Paragraph 3.B., WORK INSTRUCTIONS
are in Paragraph 1.E., Compliance.
B. WORK INSTRUCTIONS
CAUTION: BEFORE REMOVAL OF ANY FASTENER ON THE OVERWING SUPPORT FITTING,
SUPPORT THE WEIGHT OF THE ENGINE TO PREVENT POSSIBLE DAMAGE TO
THE STRUT STRUCTURE OR ENGINE. REFER TO 707 AIRCRAFT MAINTENANCE
MANUAL SUBJECT 71-5-0 AS AN ACCEPTED PROCEDURE.
1. At the inboard and outboard nacelle struts, remove the overwing support fitting fairings and
strut-to-wing fairings per operator's standard procedures (Ref. 707 Aircraft Maintenance Manual
Subject 12-2-0) as required to gain access to the overwing support fitting-to-wing front spar upper
chord attachments. See FIGURE 1.
2. Inspect the four overwing support fittings in accordance with FIGURE 1 for any crack at the
attachment fasteners. Repeat the inspections at the times specified in Paragraph 1.E., Compliance.
If no crack is found, reinstall the fairings.
3. For any holes in the overwing support fitting with no crack, there is an option for those holes to be
low interference cold worked to extend fatigue life in accordance with FIGURE 2.
4. For any repairs that require the removal of fasteners common to the skin or chord, defuel and
purge the wing tanks per operator's standard procedures (Ref. 707 Aircraft Maintenance Manual
Subject 28-0) and contact The Boeing Company for repair instructions, and do the repair,or replace
the cracked part.
5. If cracked overwing support fitting cannot be repaired, replace fitting in accordance with Service
Bulletin 707-3173.
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6. Upon completion of cracked part repair or replacement, refuel the wing tanks and check for leaks.
Refer to 707 Aircraft Maintenance Manual Subject 28-0 as an accepted procedure.
7. Put the airplane back to serviceable condition.
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### Page 32 (OCR)

BOEING SERVICE BULLETIN A3365
ALERT  ALERT
STRUT-TO-WING FAIRING  OVERWING FITTING
FAIRING
INBOARD AND OUTBOARD
NACELLE STRUT
WING
1)3)
WING FRONT SPAR
UPPER CHORD  2540172
FIGURE 1: OVERWING SUPPORT FITTING INSPECTION
(SHEET 1 OF 3)
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### Page 33

1. Accomplish a detailed inspection of the upper surface of the overwing support fitting for any crack
propagating from the bolt hole immediately forward of the wing front spar upper chord and from the
four fastener holes common to the fitting and the chord. At the forward bolt, also inspect the radius
between the lower flange and the central portion of the fitting for any crack propagating from the lower
edge of the hole.
2. Do a magnetic inspection of the overwing support fitting to find if the material is aluminum or steel. At
the forward bolt hole, inspect the fitting upper surface around the bolt and the flange radius with a
surface High Frequency Eddy Current (HFEC) in accordance with Boeing Nondestructive Test Manual
707/720 Airplanes, Part 6, Subject 51-00-00, Figure 4 or 23 for aluminum fittings, or Figure 24 for steel
fittings; or remove the bolt and inspect hole with an open hole HFEC inspection in accordance Boeing
Nondestructive Test Manual 707/720 Airplanes, Part 6, Subject 51-00-00, Figure 11 or 16 for aluminum
fittings, or Figure 19 for steel fittings.
NOTE: Holes bushed as a result of crack removal by oversizing require removal of the support bracket
for bushing removal and hole probe inspection. Bracket removal requires wing tank entry.
FIGURE 1: OVERWING SUPPORT FITTING INSPECTION
(SHEET 2 OF 3)
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3. At the four holes attaching the overwing support fitting to the spar chord, do an ultrasonic inspection
of the fitting holes for aluminum overwing support fittings only in accordance with Boeing Nondestructive
Test Manual 707/720 Airplanes, Part 4, Subject 57-40-07, Figure 1. Or inspect the upper surface with
a surface HFEC inspection in accordance withBoeing Nondestructive Test Manual 707/720 Airplanes,
Part 6, Subject 51-00-00, Figure 4 or 23 for aluminum fittings, or Figure 24 for steel fittings. The upper
surface HFEC inspection must be done for steel fittings.
4. If no crack is found and the bolt forward of the spar chord has been removed for inspection, reinstall
bolt with wet primer and torque as follows:
Torque
(Inch-Pounds)
Bolt Diameter
(Inches)
220 to 3603/8
370 to 6107/16
630 to 9501/2
5. If any crack is found visually, by surface HFEC inspection or ultrasonically, remove the fastener nearest
to the crack and do an open hole HFEC inspection. If no other crack is found after doing an open hole
HFEC inspection at the hole nearest to the crack, do the next step. If any crack is found during an open
hole HFEC inspection in any of the five holes in the overwing support fitting, remove the remaining
overwing support fitting fasteners in the initial inspection area, and the fasteners attaching the fitting
support bracket to the forward face of the upper chord vertical flange. Do a magnetic inspection of the
support bracket, front spar upper chord and wing skin to find if the material is aluminum or steel. Do
an open hole HFEC inspection of the fitting, wing skin, chord and bracket holes for any crack in
accordance with Boeing Nondestructive Test Manual 707/720 Airplanes, Part 6, Subject 51-00-00
Figure 11 or 16 for each aluminum part, or Figure 19 for each steel part. If no other crack is found after
doing the open hole HFEC inspection at the remaining holes in the overwing support fitting, wing skin,
chord and support bracket, do the next step.
6. If any crack is found in the overwing support fitting, support bracket, the wing skin or the spar chord,
contact The Boeing Company for repair instructions and do the repair, or replace the part.
FIGURE 1: OVERWING SUPPORT FITTING INSPECTION
(SHEET 3 OF 3)
Export Controlled ECCN: 9E991 - BOEING
PROPRIETARY - Copyright © Unpublished
Work - See page 1 for details.
Original Issue: August 17, 1979
A3365Revision 3 March 09, 2017
34 of 37
BOEING SERVICE BULLETIN A3365
ALERTALERT

### Page 35 (OCR)

BOEING SERVICE BULLETIN А3365
ALERT  ALERT
FRONT SPAR UPPER
CHORD HORIZONTAL
FLANGE
OVERWING
SUPPORT
FITTING
WING
UPPER
SUPPORT BRACKET  SKIN
+ +  +
FWD
WING
FRONT
SPAR
FITTING
WING
UPPER
FITTING  SKIN
A-A  WING FRONT SPAR  UPPER CHORD  B-B
BRACKET  2540223
_ FIGURE 2: OVERWING SUPPORT FITTING REPLACEMENT FASTENERS AND OPTIONAL COLD WORK
(SHEET 1 OF 3)
Original Issue: August 17, 1979
Revision 3 March 09, 2017  PROPRIETARY - Copyright ® Unpublished  Export Controlled ECCN: 9E991 - BOEING  A3365
Work - See page 1 for details.  35 01 37

### Page 36

1. At the bolt hole forward of the upper chord, if no crack is found, an optional low interference cold working
of the hole to a maximum of 5/8 inch diameter is permitted in accordance with 707-120 SRM 51-2-11,
707-320 SRM 51-2-11 or 720 SRM 51-2-11 for bolts if overwing support fitting is aluminum. Apply
chemical conversion coating, Type 2, Class A to hole if reamed after optional low interference cold
working. Refer to SOPM 20-43-03 as an accepted procedure.
NOTE: Airplanes changed by the initial release of Service Bulletin 707-3365 must contact Boeing for
instructions.
2. Install support bracket and install overwing fitting-to-bracket bolt with wet primer. See Table 1 for
replacement bolts. Torque fitting-to-bracket bolt as follows:
NOTE: Do not make a change to the fasteners that are in both the spar and the overwing fitting if
they were changed by Service Bulletin 707-3422.
Torque
(Inch-Pounds)
Bolt Diameter
(Inches)
370 to 6107/16
630 to 9501/2
1000 to 13009/16
3. At an overwing support fitting-to-chord fastener hole, if no crack is found, an optional low interference
cold working of the hole to a maximum of 15/32 inch diameter is permitted in accordance with 707-120
SRM 51-2-11, 707-320 SRM 51-2-11 or 720 SRM 51-2-11 for Hi-Loks if overwing support fitting is
aluminum. Apply chemical conversion coating, Type 2, Class A to hole if reamed after optional low
interference cold working. Refer to SOPM 20-43-03 as an accepted procedure.
NOTE: Airplanes changed by the initial release of Service Bulletin 707-3365 must contact Boeing for
instructions.
4. Install fastener with wet primer and restore tank sealant per operator's standard procedure. See Table
1 for replacement bolts. Select appropriate diameters and lengths to suit airplane configuration.
NOTE: Do not make a change to the fasteners that are in both the spar and the overwing fitting if
they were changed by Service Bulletin 707-3422.
TABLE 1 - Replacement Bolts
ReplacementLocation
BACB30US()P()BoltHole forward of front spar upper chord.
BACN10HR()Nut
BACW10BP (Plain or csk)Wash-
er
FIGURE 2: OVERWING SUPPORT FITTING REPLACEMENT FASTENERS AND OPTIONAL COLD WORK
(SHEET 2 OF 3)
Export Controlled ECCN: 9E991 - BOEING
PROPRIETARY - Copyright © Unpublished
Work - See page 1 for details.
Original Issue: August 17, 1979
A3365Revision 3 March 09, 2017
36 of 37
BOEING SERVICE BULLETIN A3365
ALERTALERT

### Page 37

TABLE 1 - Replacement Bolts
ReplacementLocation
BACB30MB()-()BoltHoles through fitting and chord horizontal flange.
BACC30X()Collar
BACB30NF()-()BoltHoles through bracket and chord vertical flange.
BACN10JC()Nut
BACB30FM()-()Bolt
BACB30FN()-()Bolt
BACC30M()Collar
FIGURE 2: OVERWING SUPPORT FITTING REPLACEMENT FASTENERS AND OPTIONAL COLD WORK
(SHEET 3 OF 3)
Export Controlled ECCN: 9E991 - BOEING
PROPRIETARY - Copyright © Unpublished
Work - See page 1 for details.
Original Issue: August 17, 1979
A3365Revision 3 March 09, 2017
37 of 37
BOEING SERVICE BULLETIN A3365
ALERTALERT

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