# Boeing Alert Service Bulletin 737-57A1335: No revision named

- Rights: © The Boeing Company. Filed by the FAA in regulations.gov docket FAA-2017-0772; AD 2017-23-05 incorporates this document by reference. Not covered by OpenAirDocs’ CC0 dedication.
- Document: [Boeing Alert Service Bulletin 737-57A1335](https://openairdocs.org/service-documents/boeing/737-57a1335.md)
- Title as filed: SB-737-57A1335-00--
- Pages: 37
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## Text

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### Page 1

Commercial 
Airplanes
737
Service Bulletin
ALERT
Number: 737-57A1335
Original Issue: May 24, 2017
ATA System: 5730
SUBJECT: WINGS - Plates/Skin - Upper Aft Skin at and Forward of the Rear Spar from Wing
Buttock Line 159 to 220 - Inspection
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 © 2017 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Unpublished Work.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.
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737-57A1335
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2.0

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Table of Contents
S u m m a r y  ...................................................... 5
1. PLANNING INFORMATION ........................................ 9
A . E f f e c t i v i t y  ................................................ 9
1. Airplanes ............................................. 9
2 . S p a r e s  A f f e c t e d  ........................................ 2 1
B. Concurrent Requirements ...................................... 2 1
C. Reason ................................................ 2 1
D. Description .............................................. 2 1
E. Compliance .............................................. 2 2
F . A p p r o v a l  ............................................... 2 4
G. Manpower .............................................. 2 4
H. Weight and Balance Changes .................................... 2 4
I. Electrical Load Data ......................................... 2 4
J . R e f e r e n c e s  .............................................. 2 4
1. Existing Data: ......................................... 2 4
2. Data Supplied with this Service Bulletin: ........................... 2 5
3. Installation Drawings Used in the Preparation of this Service Bulletin: ........... 2 5
K. Publications Affected ........................................ 2 5
L. Interchangeability and Intermixability of Parts ........................... 2 6
M. Software Accomplishment Summary ................................ 2 6
2. MATERIAL INFORMATION ........................................ 2 7
A. Material - Price and Availability ................................... 2 7
B. Industry Support Information .................................... 2 7
C. Parts Necessary for Each Airplane ................................. 2 7
1 . K i t s / P a r t s  ............................................ 2 7
2. Parts and Materials Supplied by the Operator ........................ 2 7
3. Parts Modified and Reidentified ................................ 2 7
4. Parts Removed and Not Replaced .............................. 2 7
D. Parts Necessary to Change Spares ................................. 2 7
E. Special Tooling - Price and Availability ............................... 2 7
F. Special Tooling Necessary to do this Service Bulletin ....................... 2 7
3. ACCOMPLISHMENT INSTRUCTIONS .................................. 2 9
A. GENERAL INFORMATION ..................................... 2 9
B. WORK INSTRUCTIONS ....................................... 3 0
FIGURE 1: LEFT WING - DETAILED INSPECTION OF THE UPPER AFT SKIN FROM WBL 159 TO WBL
2 2 0............................................... 3 2
FIGURE 2: RIGHT WING - DETAILED INSPECTION OF THE UPPER AFT SKIN FROM WBL 159 TO WBL
2 2 0............................................... 3 4
APPENDIX A: LOGIC DIAGRAM FOR PARAGRAPH 1.E. COMPLIANCE: TABLE 1: DETAILED INSPECTION
OF THE UPPER AFT SKIN ON THE LEFT OR RIGHT WING FROM WING BUTTOCK LINE
(WBL) 159 TO WBL 220 .................................... 3 6
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Commercial 
Airplanes
737
Service Bulletin
ALERT
SummaryNumber: 737-57A1335Original Issue: May 24, 2017
ATA System: 5730
SUBJECT: WINGS - Plates/Skin - Upper Aft Skin at and Forward of the Rear Spar from Wing
Buttock Line 159 to 220 - Inspection
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
Accomplishment of this service bulletin will make sure that cracks are found in the upper aft skin (inspar upper
skin) of the left and right wing at and forward of the rear spar from Wing Buttock Line (WBL) 159 to WBL 220.
If this service bulletin is not done, undetected cracks in the upper aft skin can lead to the inability of a principal
structural element to sustain flight load which could adversely affect the structural integrity of the airplane.
While performing inspections in accordance with SB 737-57-1318, one operator reported two crack indications
in the right wing upper aft skin originating from fastener holes common to the rear spar upper chord at WBL
172.30 and WBL 197.38. The cracks were found on airplanes with 58,148 flight hours and 45,512 flight cycles
to 64,204 flight hours and 51,409 flight cycles. Stresses are locally influenced by the bend in the rear spar
causing higher cyclic fatigue stresses.
This service bulletin provides instructions to inspect the upper aft skin and forward of the rear spar for any crack
from WBL 159 to WBL 220 and make sure any crack is found and repaired before it reaches a critical length.
Boeing Fleet Team Digest (FTD) 737 FTD 57-16003 is related to this service bulletin.
Boeing Service Related Problem (SRP) 737-SRP-57-0305 is related to this service bulletin.
This table is provided to operators for planning purposes only. Refer to the applicable sections for more
information.
ReferenceAffectedPlanning Data
Paragraph 1.A.2., Spares AffectedNoSpares Affected
Paragraph 1.E., Compliance and Paragraph
1.F., Approval
YesAD Related
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ReferenceAffectedPlanning Data
Paragraph 1.H., Weight and Balance ChangesNoWeight and Balance Change
Paragraph 1.I., Electrical Load DataNoElectrical Load Changed
Paragraph 1.K., Publications AffectedNoPublications 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/PartsNoKits/Parts Required
Paragraph 2.C.2., Parts and Materials Supplied
by the Operator
NoOperator Supplied Parts/Material
Paragraph 2.F., Special Tooling Necessary to
do this Service Bulletin
NoSpecial Tooling Required
ACTION
Group 1:
Boeing endorses the FAA rules related to Limit of Validity (LOV) and recommends immediate and permanent
removal from service of any airplanes upon reaching the LOV, whether or not it is operated under FAA jurisdiction.
As such, Boeing no longer provides maintenance instructions for airplanes that have accumulated flight cycles
beyond the LOV. 737 Classic airplanes line numbers 1-291 have accumulated flight cycles beyond the LOV of
the maintenance program. 14 CFR 121.1115 and 129.115 prohibit operation of an airplane beyond its LOV.
Group 2:
Deactivate the trailing edge flap system. Do a detailed inspection for any crack in the upper aft skin from WBL
159 to WBL 220. If any crack is found, contact The Boeing Company for repair instructions and do the repair.
Repeat the detailed inspection in the unrepaired areas. If no crack is found, repeat the detailed inspection.
Activate the trailing edge flap system.
EFFECTIVITY
All 737-100, 737-200, 737-200C, 737-300, 737-400, and 737-500 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 given in this service bulletin.
MANPOWER
Refer to Paragraph 1.G., Manpower.
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### Page 7 (OCR)

BOEING SERVICE BULLETIN 737-57A1335
ALERT  ALERT
MATERIAL INFORMATION
None.
THE UPPER AFT SKIN. IF ANY CRACK IS FOUND,  DO A DETAILED INSPECTION FOR ANY CRACK IN  LEFT WING
CONTACT THE BOEING COMPANY FOR REPAIR
INSTRUCTIONS AND DO THE REPAIR AND REPEAT
THE DETAILED INSPECTION IN THE UNREPAIRED  WBL
AREAS. IF NO CRACK IS FOUND, REPEAT THE  DETAILED INSPECTION.  WBL  17:  159
S-6
WBL  S-5
187
_ S-4
WBL
200
WBL
220
* +
NBD
LEFT WING SHOWN, RIGHT WING OPPOSITE
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Commercial 
Airplanes
737
Service Bulletin
ALERT
Number: 737-57A1335
Original Issue: May 24, 2017
ATA System: 5730
SUBJECT: WINGS - Plates/Skin - Upper Aft Skin at and Forward of the Rear Spar from Wing
Buttock Line 159 to 220 - Inspection
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 737-100, 737-200, 737-200C, 737-300, 737-400, and
737-500 Airplanes in 2 Groups. The Variable Numbers and Group Information for the applicable
airplanes is given below.
Refer to Service Bulletin Index D6-19567 Part 3 for Airplane Variable Number, Line Number, and
Serial Number data.
DESCRIPTIONCONFIGURATIONGROUP
Airplane line numbers 1-291-1
Airplane line numbers 292-3132-2
Airplane Models:
737-100, 737-200, 737-200C, 737-300, 737-400, 737-500
GroupVariable Number
1PA001 - PA022
1PA099
1PA231 - PA232
1PC001 - PC005
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GroupVariable Number
1PG001 - PG075
1PG199
1PG201 - PG230
1PG251 - PG255
1PG271 - PG279
1PG301 - PG314
1PG331 - PG332
1PG351 - PG356
1PG375
1PG401 - PG403
1PG431 - PG442
1PG471 - PG475
1PG501 - PG505
1PG571 - PG583
2PG584 - PG586
1PG621 - PG630
1PG651 - PG652
1PG701 - PG705
2PH001
2PH011 - PH013
2PH021 - PH024
1PH701 - PH715
1PH731 - PH732
1PH741 - PH742
2PH743
1PJ001 - PJ002
2PJ003 - PJ009
1PJ031 - PJ032
1PJ071 - PJ072
1PJ101 - PJ104
2PJ105 - PJ119
2PJ201 - PJ219
2PJ301 - PJ302
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GroupVariable Number
2PJ551 - PJ561
2PJ601 - PJ615
2PJ811
2PJ816 - PJ817
2PK026 - PK029
2PK041 - PK053
2PK061 - PK070
2PK081 - PK082
2PK091 - PK099
2PK101 - PK103
2PK111 - PK120
2PK141 - PK146
2PK201 - PK204
2PK211 - PK223
2PK231 - PK241
2PK251 - PK258
2PK271 - PK274
2PK281 - PK289
2PK291
2PK301 - PK318
2PK341
2PK351 - PK361
2PK391
2PK431 - PK433
2PK451 - PK452
2PK461 - PK469
2PK495
2PK501 - PK504
2PK511 - PK515
2PK519
2PK521 - PK528
2PK541 - PK565
2PK581
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GroupVariable Number
2PK591 - PK599
2PK601 - PK617
2PK621 - PK637
2PK641 - PK642
2PK661 - PK666
2PK671 - PK681
2PK691 - PK697
2PK711 - PK716
2PK731 - PK765
2PK771 - PK779
2PK801 - PK804
2PK819 - PK827
2PK830
2PK861 - PK863
2PK871 - PK874
2PK881 - PK884
2PK901 - PK938
2PK971 - PK974
2PL001 - PL028
2PL061
2PL081
2PL101 - PL113
2PL151
2PL171 - PL172
2PL201 - PL203
2PL221
2PL401 - PL417
2PL421
2PL441
2PL451 - PL456
2PL471
2PL491
2PL501 - PL506
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GroupVariable Number
2PL551 - PL562
2PL581
2PL601 - PL603
2PL611
2PL621 - PL626
2PL631 - PL632
1PL711 - PL712
1PL716
2PL717 - PL747
2PL756
2PL758
2PL761 - PL770
2PL781 - PL788
2PL793
1PL801 - PL803
2PM001 - PM006
2PM016 - PM017
2PM021 - PM023
2PM051 - PM066
2PM101 - PM119
2PM141 - PM142
2PM171
2PM181
2PM251 - PM255
2PM281 - PM283
2PM381 - PM399
2PM401 - PM417
2PM541 - PM564
2PN001 - PN002
2PN021 - PN043
2PN081 - PN086
2PN101 - PN117
2PN131 - PN163
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GroupVariable Number
2PN401 - PN420
2PN431 - PN433
2PN451 - PN456
2PN471 - PN474
2PN481
2PN491 - PN493
2PN501 - PN502
2PN511 - PN512
2PN521
2PP001 - PP054
2PP101 - PP169
2PP181 - PP199
2PP201 - PP205
2PP221
2PP231 - PP243
2PP281 - PP286
2PP301 - PP305
2PP351 - PP353
2PP376 - PP384
2PP391 - PP393
2PP401 - PP440
2PP471 - PP475
2PP501 - PP522
2PP631 - PP634
2PP651 - PP652
2PP671 - PP699
2PP701 - PP733
2PP771 - PP779
2PP801 - PP808
2PP821 - PP827
2PP831 - PP848
2PP851 - PP852
2PP861 - PP877
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GroupVariable Number
2PP891 - PP899
2PP901 - PP936
2PP946 - PP948
2PP951 - PP952
2PP961 - PP967
2PP981 - PP991
2PP993
2PQ001 - PQ016
2PQ026 - PQ041
2PQ051 - PQ092
2PQ101 - PQ199
2PQ201 - PQ202
2PQ221 - PQ237
2PQ241 - PQ243
2PQ251 - PQ267
2PQ281 - PQ299
2PQ301 - PQ307
2PQ331 - PQ332
2PQ341 - PQ348
2PQ361 - PQ373
2PQ391 - PQ395
2PQ401 - PQ418
2PQ421
2PQ431 - PQ438
2PQ447 - PQ448
2PQ451
2PQ454
2PQ471 - PQ475
2PQ479 - PQ481
2PQ486 - PQ487
2PQ491 - PQ493
2PQ771 - PQ772
2PQ791 - PQ793
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GroupVariable Number
2PQ801 - PQ805
2PQ931 - PQ935
2PQ951
2PQ971 - PQ997
2PR001 - PR017
2PR021 - PR034
2PR041 - PR045
2PR061 - PR072
2PR077 - PR082
2PR091 - PR092
2PR096
2PR101
2PR121 - PR122
2PR131 - PR132
2PR141 - PR143
2PR161 - PR172
2PR181
2PS601 - PS631
2PS636 - PS638
2PS641 - PS644
2PS651 - PS657
2PS666 - PS669
2PS691 - PS692
2PS701 - PS706
2PS751 - PS799
2PS811
2PS836 - PS837
2PS841 - PS846
2PS851 - PS852
2PS856
2PS861 - PS863
2PS866 - PS868
2PS871 - PS874
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GroupVariable Number
2PS896 - PS897
2PS901 - PS941
2PS956 - PS957
2PS961 - PS963
2PS971 - PS978
2PT001 - PT015
2PT021 - PT031
2PT041 - PT064
2PT101 - PT105
2PT121 - PT138
2PT146 - PT148
2PT161 - PT170
2PT181 - PT188
2PT211 - PT220
2PT295
2PT301 - PT309
2PT331 - PT360
2PT381 - PT399
2PT401 - PT438
2PT501 - PT517
2PT561 - PT565
2PT581 - PT586
2PT611 - PT621
2PT641 - PT644
2PT651 - PT656
2PT671 - PT672
2PT681 - PT685
2PT701 - PT703
2PT716 - PT717
2PT721 - PT725
2PT801 - PT834
2PT851 - PT854
2PT871 - PT886
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GroupVariable Number
2PT901 - PT930
2PT971 - PT973
2PT981 - PT985
2PT996
2PU001 - PU025
2PU301
2PU311 - PU313
2PV001 - PV055
2PV201 - PV209
2PV226 - PV229
2PV231 - PV237
2PV271 - PV272
2PV281 - PV287
2PV296
2PV301 - PV302
2PV351
2PV356 - PV357
2PW001 - PW054
2PW061 - PW068
2PW072
2PW086 - PW088
2PW091 - PW094
2PW101 - PW102
2PW106
2PW111 - PW120
2PW156 - PW157
2PW161 - PW171
2PW201 - PW252
2PW261 - PW268
2PW271 - PW276
2PW278
2PW281 - PW293
2PW296
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GroupVariable Number
2PW301 - PW327
2PW401 - PW408
2PW411 - PW418
2PW421 - PW424
2PW431 - PW435
2PW441 - PW450
2PW461 - PW467
2PW501 - PW504
2PW511 - PW522
2PW524 - PW550
2PW556 - PW557
2PW561 - PW564
2PW571 - PW576
2PW591 - PW596
2PW611 - PW622
2PW631 - PW637
2PW661 - PW662
2PW681 - PW683
2PW701 - PW702
2PW711 - PW717
2PW741 - PW742
2PW761
2PW771
2PW831
2PW851 - PW856
1PX071
1PX701
1PY001 - PY008
1PY021
2PY022
1PY031
2PY036 - PY037
2PY046 - PY048
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GroupVariable Number
2PY051 - PY053
2PY056 - PY057
2PY101 - PY103
2PY111 - PY113
2PY131 - PY135
2PY141 - PY143
2PY151 - PY154
2PY156 - PY157
2PY161 - PY162
2PY166
2PY191
2PY201
2PY221 - PY222
2PY231
2PY241 - PY244
2PY270 - PY275
2PY281
2PY286
1PY301 - PY304
1PY321 - PY323
1PY341 - PY346
1PY361 - PY362
1PY381
2PY401
2PY409 - PY411
2PY421 - PY422
2PY441
2PY451
2PY461 - PY463
2PY591 - PY595
2PY611 - PY612
2PY621
2PY631
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GroupVariable Number
2PY651
2PY671 - PY672
2PY721
2PY741
2. Spares Affected
None.
B. Concurrent Requirements
None.
C. Reason
Accomplishment of this service bulletin will make sure that cracks are found in the upper aft skin (inspar
upper skin) of the left and right wing at and forward of the rear spar from Wing Buttock Line (WBL) 159
to WBL 220. If this service bulletin is not done, undetected cracks in the upper aft skin can lead to the
inability of a principal structural element to sustain flight load which could adversely affect the structural
integrity of the airplane.
While performing inspections in accordance with SB 737-57-1318, one operator reported two crack
indications in the right wing upper aft skin originating from fastener holes common to the rear spar
upper chord at WBL 172.30 and WBL 197.38. The cracks were found on airplanes with 58,148 flight
hours and 45,512 flight cycles to 64,204 flight hours and 51,409 flight cycles. Stresses are locally
influenced by the bend in the rear spar causing higher cyclic fatigue stresses.
This service bulletin provides instructions to inspect the upper aft skin and forward of the rear spar for
any crack from WBL 159 to WBL 220 and make sure any crack is found and repaired before it reaches
a critical length.
Boeing Fleet Team Digest (FTD) 737 FTD 57-16003 is related to this service bulletin.
Boeing Service Related Problem (SRP) 737-SRP-57-0305 is related to this service bulletin.
D. Description
Group 1:
Boeing endorses the FAA rules related to Limit of Validity (LOV) and recommends immediate and
permanent removal from service of any airplanes upon reaching the LOV, whether or not it is operated
under FAA jurisdiction. As such, Boeing no longer provides maintenance instructions for airplanes that
have accumulated flight cycles beyond the LOV. 737 Classic airplanes line numbers 1-291 have
accumulated flight cycles beyond the LOV of the maintenance program. 14 CFR 121.1115 and 129.115
prohibit operation of an airplane beyond its LOV.
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Group 2:
Deactivate the trailing edge flap system. Do a detailed inspection for any crack in the upper aft skin
from WBL 159 to WBL 220. If any crack is found, contact The Boeing Company for repair instructions
and do the repair; and repeat the detailed inspection in the unrepaired areas. If no crack is found,
repeat the detailed inspection. Activate the trailing edge flap system.
The work in this service bulletin is done in the maintenance zone(s) given below.
Group 1:
Affected Maintenance Zones
ZoneModel
3-5, 4-5737-100, 737-200, 737-200C
Group 2:
Affected Maintenance Zones
ZoneModel
3-5, 4-5737-200, 737-200C
Group 2:
Affected Maintenance Zones
ZoneModel
305, 405737-300, 737-400, 737-500
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.
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.
Accomplish the required actions, based on the applicable conditions in Table 1, in accordance with
Paragraph 3. Accomplishment Instructions.
A logic diagram showing compliance tasks and compliance times is included as an aid in Appendix A.
Group 1:
Boeing endorses the FAA rules related to Limit of Validity (LOV) and recommends immediate and
permanent removal from service of any airplanes upon reaching the LOV, whether or not it is operated
under FAA jurisdiction. As such, Boeing no longer provides maintenance instructions for airplanes that
have accumulated flight cycles beyond the LOV. 737 Classic airplanes line numbers 1-291 have
accumulated flight cycles beyond the LOV of the maintenance program. 14 CFR 121.1115 and 129.115
prohibit operation of an airplane beyond its LOV.
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Group 2:
Table 1: Detailed Inspection of the upper aft skin on the left and right wing from Wing Buttock Line
(WBL) 159 to WBL 220
Repeat Interval
(Not to Exceed)
Compliance Time (Whichever
Occurs Later)
ActionCondition
-Within 4,500
flight cycles af-
ter the original
issue date of
this Service Bul-
letin.
Before 45,000
total flight cy-
cles.
Do PART 1: DETAILED
INSPECTION OF THE
UPPER WING AFT SKIN
FROM WBL 159 TO 220
for any crack.
Airplanes that have not
done an Open Hole High
Frequency Eddy Current
(HFEC) inspection of all the
fastener holes in the inspec-
tion area. (a)
-Within 4,500
flight cycles af-
ter the original
issue date of
this Service Bul-
letin.
Before 45,000
total flight cycles
or within 9,000
flight cycles af-
ter the most re-
cent open hole
HFEC inspec-
tion, whichever
occurs later.
Do PART 1: DETAILED
INSPECTION OF THE
UPPER WING AFT SKIN
FROM WBL 159 TO 220
for any crack.
Airplanes that have done
an Open Hole HFEC in-
spection of all the fastener
holes in the inspection
area. (a)
-Before further flight.CONDITION 1 (ACTION
1): Contact The Boeing
Company for repair in-
structions and do the re-
pair.
CONDITION 1: ANY
CRACK FOUND
4,500 flight cycles.-CONDITION 1 (ACTION
2): Repeat PART 1: DE-
TAILED INSPECTION
OF THE UPPER AFT
SKIN FROM WBL 159
TO WBL 220 for any
crack in the unrepaired
areas.
4,500 flight cycles.-Repeat PART 1: DE-
TAILED INSPECTION
OF THE UPPER AFT
SKIN FROM WBL 159
TO WBL 220 for any
crack.
CONDITION 2: NO
CRACK FOUND
(a) Accomplishment of the open hole HFEC inspection of all the fastener holes in the inspection area is met
if the inspection was done in accordance with 737 NDT Manual Part 6, 51-00-00 Procedure 1, Procedure
11 or Procedure 16 during the accomplishment of one the following:
– 737-300 SRM 57-20-10 Repair 4, 737-400 SRM 57-20-10 Repair 4, or 737-500 SRM 57-20-10 Repair
4 for 737-300/400/500 Airplanes.
– Boeing ODA FAA Form 8100-9 approved upper rear spar chord replacement repair.
The inspection area is defined in FIGURE 1 and FIGURE 2.
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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 table below shows 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
Elapsed HoursTask HoursNumber of PersonsTask
0.750.751Preparation
1.001.001Figure 1
1.001.001Figure 2
0.750.751Restoration
3.503.50TOTAL FOR EACH AIRPLANE
H. Weight and Balance Changes
None.
I. Electrical Load Data
Not changed.
J. References
1. Existing Data:
a. Boeing Service Bulletin 737-57A1328, 737-57A1326, 737-57A1329
b. Boeing Service Related Problem (SRP) 737-SRP-57-0305
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c. Service Bulletin Index D6-19567
d. 737 Fleet Team Digest (FTD) 57-16003
e. 737 Non-Destructive Testing (NDT) Manual Part 6, 51-00-00
f. 737-100/200 Aircraft Maintenance Manual (AMM) 27-51-00
g. 737-300/400/500 Aircraft Maintenance Manual (AMM) 27-51-00
h. 737-300 Structural Repair Manual (SRM) 57-20-10
i. 737-400 Structural Repair Manual (SRM) 57-20-10
j. 737-500 Structural Repair Manual (SRM) 57-20-10
2. Data Supplied with this Service Bulletin:
None.
3. Installation Drawings Used in the Preparation of this Service Bulletin:
TitleDrawing Number
Panel Instl -Upper Inbd. Fixed Trailing Edge, Wing.65-50820
Rib Installation-Inspar. WBL 227.065-45450
Rib Installation-Inspar. WBL 198.6065-45449
Rib Installation-Inspar. WBL 183.4065-45447
Rib Installation-Inspar. WBL 157.065-45446
Rib Installation-Inspar. WBL 135.565-45445
Panel Instl - Inspar Wing, Upper65-45407
Rear Spar Installation-Wing65-45321
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:
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.
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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 procedures given in this service bulletin.
C. Parts Necessary for Each Airplane
1. Kits/Parts
None.
2. Parts and Materials Supplied by the Operator
None.
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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### Page 29

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 737 Structural Repair Manual,
Chapter 51.
— Values for airframe maintenance tasks are included in Chapter 20 of 737
Aircraft 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 737
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. 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.
6. 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.
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7. Refer to Appendix A for logic diagram. 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.
8. 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.
9. Use of colors in Figures is based on guidance from the ATA e-Business Program
(ATA) iSpec 2200.
10. 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.
11. The compliance times for the actions in Paragraph 3.B., WORK INSTRUCTIONS
are in Paragraph 1.E., Compliance.
12. 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. If a step or sub-step is labeled
"RC Exempt," then the RC requirement is removed from that step or sub-step. An
Alternative Method of Compliance (AMOC) is required for any deviations to RC steps,
including sub-steps 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. Group 1:
Boeing endorses the FAA rules related to Limit of Validity (LOV) and recommends immediate and
permanent removal from service of any airplanes upon reaching the LOV, whether or not it is
operated under FAA jurisdiction. As such, Boeing no longer provides maintenance instructions for
airplanes that have accumulated flight cycles beyond the LOV. 737 Classic airplanes line numbers
1-291 have accumulated flight cycles beyond the LOV of the maintenance program. 14 CFR
121.1115 and 129.115 prohibit operation of an airplane beyond its LOV.
2. Group 2:
a. Deactivate the trailing edge flap system. Refer to 737-100/200 AMM 27-51-00 and
737-300/400/500 AMM 27-51-00 as an accepted procedure.
b. RC - Do PART 1: DETAILED INSPECTION OF THE UPPER WING AFT SKIN FROM WBL
159 TO 220 for any crack.
(1) CONDITION 1: ANY CRACK FOUND
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(a) CONDITION 1 (ACTION 1): Contact The Boeing Company for repair instructions
and do the repair.
(b) CONDITION 1 (ACTION 2): Repeat PART 1: DETAILED INSPECTION OF THE
UPPER WING AFT SKIN FROM WBL 159 TO 220 for any crack in the unrepaired
areas at the times specified in Paragraph 1.E., Compliance.
(2) CONDITION 2: NO CRACK FOUND
(a) Repeat PART 1: DETAILED INSPECTION OF THE UPPER WING AFT SKIN FROM
WBL 159 TO 220 for any crack at the times specified in Paragraph 1.E., Compliance.
c. Activate the trailing edge flap system. Refer to 737-100/200 AMM 27-51-00 and
737-300/400/500 AMM 27-51-00 as an accepted procedure.
d. Put the airplane back to a serviceable condition.
Group 2:
PART 1: DETAILED INSPECTION OF THE UPPER WING AFT SKIN FROM WBL 159 TO 220
1. Do a detailed inspection of the upper aft skin for any crack in accordance with the figures below:
Right WingLeft Wing
FIGURE 2FIGURE 1
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### Page 32 (OCR)

BOEING SERVICE BULLETIN 737-57A1335
ALERT  ALERT
_A
LEFT WING
WBL WBL
UPPER  AFT  WBL  171  159 157
SKIN
_S-6
WBL  _S-5
187
. S-4
WBL
198
REAR
SPAR
NBD
25.0
A-A  I INSPECTION ZONE  2559000
FIGURE 1: LEFT WING - DETAILED INSPECTION OF THE UPPER AFT SKIN FROM WBL 159 TO WBL
220
(SHEET 1 OF 2)
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### Page 33

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
(a)(b)--UPPER AFT SKINInspect1
(a) Do a detailed inspection for any crack in the area shown. The boundary of the inspection area is 1.00
inch from the edge of the outer fasteners in the inspection area.
(b) It is not necessary to do a detailed inspection in the areas of upper aft skin that are covered by an existing
external repair configuration defined in Boeing Service Bulletin(s) 737-57A1326, 737-57A1328, or 737-
57A1329. In addition, it is not necessary to do a detailed inspection in the areas of upper aft skin that are
covered by an external repair installed as a result of the inspection done as specified in Boeing Service
Bulletin(s) 737-57A1326, 737-57A1328, or 737-57A1329.
FIGURE 1: LEFT WING - DETAILED INSPECTION OF THE UPPER AFT SKIN FROM WBL 159 TO WBL
220
(SHEET 2 OF 2)
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### Page 34 (OCR)

BOEING SERVICE BULLETIN 737-57A1335
ALERT  ALERT
RIGHT WING
WBLWBL
157 159
AFT
SKIN
S-6
S-5
WBL
198
1* +
REAR
SPAR
25.0
INSPECTION ZONE  A-A  2559002
FIGURE 2: RIGHT WING - DETAILED INSPECTION OF THE UPPER AFT SKIN FROM WBL 159 TO WBL
(SHEET 1 OF 2)
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### Page 35

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
(a)(b)--UPPER AFT SKINInspect1
(a) Do a detailed inspection for any crack in the area shown. The boundary of the inspection area is 1.00
inch from the edge of the outer fasteners in the inspection area.
(b) It is not necessary to do a detailed inspection in the areas of upper aft skin that are covered by an existing
external repair configuration defined in Boeing Service Bulletin(s) 737-57A1326, 737-57A1328, or 737-
57A1329. In addition, it is not necessary to do a detailed inspection in the areas of upper aft skin that are
covered by an external repair installed as a result of the inspection done as specified in Boeing Service
Bulletin(s) 737-57A1326, 737-57A1328, or 737-57A1329.
FIGURE 2: RIGHT WING - DETAILED INSPECTION OF THE UPPER AFT SKIN FROM WBL 159 TO WBL
220
(SHEET 2 OF 2)
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### Page 36

Logic diagrams are provided as an aid only. Information contained in Paragraph 1.E., Compliance is the primary
source for compliance times. Information contained in Paragraph 3.B., Work Instructions is the primary source
for tasks required for compliance.
1. The table below gives the description for the parts and conditions called out in the logic diagrams.
DescriptionTitle
DETAILED INSPECTION OF THE UPPER WING AFT SKIN FROM WBL 159
TO 220
PART 1
ANY CRACK FOUNDCONDITION 1
NO CRACK FOUNDCONDITION 2
2. The table below gives the description for the flag notes called out in the logic diagram.
DescriptionFlag Note Letter
Accomplishment of the open hole HFEC inspection of all the fastener holes
in the inspection area is met if the inspection was done in accordance with
737 NDT Manual Part 6, 51-00-00 Procedure 1, Procedure 11 or Procedure
16 during the accomplishment of one the following:
(a)
– 737-300 SRM 57-20-10 Repair 4, 737-400 SRM 57-20-10 Repair 4, or
737-500 SRM 57-20-10 Repair 4 for 737-300/400/500 Airplanes.
– Boeing ODA FAA Form 8100-9 approved upper rear spar chord replace-
ment repair.
The inspection area is defined in FIGURE 1 and FIGURE 2.
APPENDIX A:  LOGIC DIAGRAM FOR PARAGRAPH 1.E. COMPLIANCE: TABLE 1: DETAILED INSPECTION
OF THE UPPER AFT SKIN ON THE LEFT OR RIGHT WING FROM WING BUTTOCK LINE (WBL) 159 TO
WBL 220
(SHEET 1 OF 2)
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### Page 37 (OCR)

BOEING SERVICE BULLETIN 737-57A1335
ALERT  ALERT
AIRPLANES THAT HAVE NOT DONE AN
OPEN HOLE HFEC INSPECTION OF ALL
THE FASTENER HOLES IN THE
INSPECTION AREA
(a) >
AIRPLANES THAT HAVE DONE AN OPEN
HOLE HFEC INSPECTION OF ALL THE
FASTENER HOLES IN THE INSPECTION
AREA
(a)
WHICHEVER OCCURS LATER  WHICHEVER OCCURS LATER
BEFORE 45,000  TOTAL FLIGHT  CYCLES  ORIGINAL ISSUE  FLIGHT CYCLES  DATE OF THIS  WITHIN 4,500  AFTER THE  BEFORE 45,000 TOTAL  WITHIN 9,000 FLIGHT  CYCLES AFTER THE  FLIGHT CYCLES OR  LAST OPEN HOLE  ORIGINAL ISSUE DATE  WITHIN 4,500 FLIGHT  CYCLES AFTER THE
SERVICE BULLETIN  HFEC INSPECTION,  OF THIS SERVICE
BULLETIN
WHICHEVER OCCURS
LATER
DO PART 1
CONDITION 1  CONDITION 2
BEFORE FURTHER  NOT TO EXCEED
FLIGHT  4,500 FLIGHT CYCLES
CONDITION 1 (ACTION 1):  REPEAT PART 1
CONTACT THE BOEING
COMPANY FOR REPAIR
INSTRUCTIONS AND DO THE
REPAIR
NOT TO EXCEED 4,500
FLIGHT CYCLES
CONDITION 1 (ACTION 2):
REPEAT PART 1 IN THE
UNREPAIRED AREAS  2559505
APPENDIX A: LOGIC DIAGRAM FOR PARAGRAPH 1.E. COMPLIANCE: TABLE 1: DETAILED INSPECTION
OF THE UPPER AFT SKIN ON THE LEFT OR RIGHT WING FROM WING BUTTOCK LINE (WBL) 159 TO
(SHEET 2 OF 2)
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