# Boeing Alert Service Bulletin 737-53A1366: No revision named

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- Document: [Boeing Alert Service Bulletin 737-53A1366](https://openairdocs.org/service-documents/boeing/737-53a1366.md)
- Title as filed: SB-737-53A1366-00
- Pages: 40
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## Text

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### Page 1

Commercial 
Airplanes
737
Service Bulletin
ALERT
Number: 737-53A1366
Original Issue: May 17, 2016
ATA System: 5311
SUBJECT: FUSELAGE - Frames and Bulkheads - Emergency Exit Frame Inboard Chord -
Inspections
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 © 2016 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Unpublished Work.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: May 17, 2016
737-53A1366
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3.0

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### Page 3

Table of Contents
Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
1. PLANNING INFORMATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
A. Effectivity . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
1. Airplanes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
2. Spares Affected . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
B. Concurrent Requirements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
C. Reason . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
D. Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
E. Compliance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
F. Approval . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
G. Manpower . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18
H. Weight and Balance Changes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18
I. Electrical Load Data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18
J. References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19
1. Existing Data: . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19
2. Data Supplied with this Service Bulletin: . . . . . . . . . . . . . . . . . . . . . . . . . . . 19
3. Installation Drawings Used in the Preparation of this Service Bulletin: . . . . . . . . . . . 19
K. Publications Affected . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19
L. Interchangeability and Intermixability of Parts . . . . . . . . . . . . . . . . . . . . . . . . . . . 19
M. Software Accomplishment Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19
2. MATERIAL INFORMATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21
A. Material - Price and Availability . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21
B. Industry Support Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21
C. Parts Necessary for Each Airplane . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21
1. Kits/Parts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21
2. Parts and Materials Supplied by the Operator . . . . . . . . . . . . . . . . . . . . . . . . 21
3. Parts Modified and Reidentified . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21
4. Parts Removed and Not Replaced . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21
D. Parts Necessary to Change Spares . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21
E. Special Tooling - Price and Availability . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21
F. Special Tooling Necessary to do this Service Bulletin . . . . . . . . . . . . . . . . . . . . . . . 21
3. ACCOMPLISHMENT INSTRUCTIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23
A. GENERAL INFORMATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23
B. WORK INSTRUCTIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24
FIGURE 1: DETAILED INSPECTION AND HFEC INSPECTION OF LEFT SIDE BS 616 FRAME INBOARD
CHORD [Group 1] . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27
FIGURE 2: DETAILED INSPECTION AND HFEC INSPECTION OF RIGHT SIDE BS 616 FRAME INBOARD
CHORD [Group 1] . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30
FIGURE 3: DETAILED INSPECTION AND HFEC INSPECTION OF LEFT SIDE BS 578 FRAME INBOARD
CHORD [Group 2] . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33
FIGURE 4: DETAILED INSPECTION AND HFEC INSPECTION OF RIGHT SIDE BS 578 FRAME INBOARD
CHORD [Group 2] . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36
APPENDIX A: LOGIC DIAGRAM FOR PARAGRAPH 1.E. COMPLIANCE: TABLE 1: DETAILED INSPECTION
AND HFEC INSPECTION FOR ANY CRACK AT THE FRAME INBOARD CHORD, FORWARD
OF THE EMERGENCY EXIT OPENING, LEFT AND RIGHT SIDE . . . . . . . . . . . . . 39
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Commercial 
Airplanes
737
Service Bulletin
ALERT
SummaryNumber: 737-53A1366Original Issue: May 17, 2016
ATA System: 5311
SUBJECT: FUSELAGE - Frames and Bulkheads - Emergency Exit Frame Inboard Chord -
Inspections
THIS BULLETIN IS SENT TO THE OPERATORS OF RECORD OF THE AIRPLANES SHOWN IN PARAGRAPH
1.A., EFFECTIVITY. IF AN AIRPLANE HAS BEEN LEASED OR SOLD, SEND THIS SERVICE BULLETIN TO
THE NEW OPERATOR. IF APPLICABLE SPARES HAVE BEEN SOLD, SEND THIS SERVICE BULLETIN TO
THE NEW OWNER.
CONCURRENT REQUIREMENTS
None.
BACKGROUND
This service bulletin gives instructions to inspect the frame inner chord below stringer S-11 for any crack. The
frame for 737-300/-500 is at BS 616 forward of the emergency exit, and for 737-400 it is at BS 578 forward of
the forward emergency exit on both sides of the airplane. An operator of a 737-300 reported a crack of
approximately 1.00 inch in the BS 616 frame inboard chord during Supplemental Structural Inspection Document
(SSID) inspections. The crack was located at the lowest fastener hole of the inboard chord inboard strap below
stringer S-11R. The airplane had 75,584 total flight hours and 63,570 total flight cycles. Cracking in the inboard
chord is the result of fatigue caused by cyclic pressurization of the fuselage. If not found and repaired, a crack
in the inboard chord of the noted frames below S-11L or S-11R could result in structural failure of the frame and
possible rapid decompression.
Boeing Fleet Team Digest (FTD) 737 FTD 53-15008 is related to this service bulletin.
This table is provided to operators for planning purposes only. Refer to the applicable sections for more
information.
ReferenceAffectedPlanning Data
Paragraph 1.A.2., Spares AffectedNoSpares Affected
Paragraph 1.E., Compliance and Paragraph
1.F., Approval
YesAD Related
Paragraph 1.H., Weight and Balance ChangesNoWeight and Balance Change
Paragraph 1.I., Electrical Load DataNoElectrical Load Changed
Paragraph 1.K., Publications AffectedNoPublications Affected
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ReferenceAffectedPlanning Data
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:
Do PART 1: DETAILED INSPECTION AND HFEC INSPECTION for any crack in the BS 616 frame inboard
chord below S-11L and S-11R at the lowest fastener of the inboard strap. If no crack is found, repeat PART 1:
DETAILED INSPECTION AND HFEC INSPECTION at the repeat interval in Paragraph 1.E., Compliance. If any
crack is found, contact The Boeing Company for repair instructions and do the repair.
Group 2:
Do PART 1: DETAILED INSPECTION AND HFEC INSPECTION for any crack in the BS 578 frame inboard
chord below S-11L and S-11R at the lowest fastener of the inboard strap. If no crack is found, repeat PART 1:
DETAILED INSPECTION AND HFEC INSPECTION at the repeat interval in Paragraph 1.E., Compliance. If any
crack is found, contact The Boeing Company for repair instructions and do the repair.
EFFECTIVITY
All 737-300/400/500 Airplane(s). Refer to Paragraph 1.A.1., Airplanes, for the list of affected airplane(s).
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 procedures given in this service bulletin.
MANPOWER
Elapsed HoursTotal Task HoursTask
4.307.30Inboard Chord Inspections
Refer to Paragraph 1.G., Manpower.
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BOEING SERVICE BULLETIN 737-53A1366
ALERT  ALERT
MATERIAL INFORMATION
None.
STA  616  STA  578
STA  STA
616  • 578
• D
GROUP 1  GROUP 2
737-300 AND 737-500  737-400
GROUP 1 STA 616
GROUP 2 STA 578  - S-9L
- S-10L
_ S-11L  DO PART 1: DETAILED INSPECTION
AND HFEC INSPECTION FOR ANY
CRACK IN THE FRAME INBOARD
CHORD BELOW S-11L AND S-11R AT
THE LOWEST FASTENER OF THE
INBOARD STRAP.
S-13L
• S-14L
INBOARD STRAP
- S-15L
01010  STRINGER 11
TYPICAL CRACK •
INBOARD FLANGE OF  • FRAME WEB
FRAME INBOARD CHORD
LEFT SIDE SHOWN
RIGHT SIDE SIMILAR
(TYPICAL)  INBD
INSPECTION AREA
GROUP 1:
STA 616: 737-300/-500
GROUP 2:
STA 578: 737-400
FRAME INBOARD CHORD
VIEW LOOKING AFT
(TYPICAL)  B  2478988
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Commercial 
Airplanes
737
Service Bulletin
ALERT
Number: 737-53A1366
Original Issue: May 17, 2016
ATA System: 5311
SUBJECT: FUSELAGE - Frames and Bulkheads - Emergency Exit Frame Inboard Chord -
Inspections
THIS BULLETIN IS SENT TO THE OPERATORS OF RECORD OF THE AIRPLANES SHOWN IN PARAGRAPH
1.A., EFFECTIVITY. IF AN AIRPLANE HAS BEEN LEASED OR SOLD, SEND THIS SERVICE BULLETIN TO
THE NEW OPERATOR. IF APPLICABLE SPARES HAVE BEEN SOLD, SEND THIS SERVICE BULLETIN TO
THE NEW OWNER.
1.    PLANNING INFORMATION
A. Effectivity
1. Airplanes
This service bulletin is applicable to all 737-300, -400 and -500 airplanes, line numbers 1001-3132
in 2 Groups. The Variable Numbers and Group Information for the applicable airplanes are given
below.
Refer to Service Bulletin Index D6-19567 Part 3 for Airplane Variable Number, Line Number, and
Serial Number data.
DESCRIPTIONCONFIGURATIONGROUP
All 737-300/-500 Airplanes-1
All 737-400 Airplanes-2
Airplane Models:
737-300, 737-400, 737-500
GroupVariable Number
2PJ301 - PJ302
2PJ551 - PJ561
2PJ601 - PJ615
2PJ811
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GroupVariable Number
2PJ816 - PJ817
1PM381 - PM399
1PM401 - PM417
1PM541 - PM550
2PM551 - PM564
1PP001 - PP054
1PP101 - PP169
1PP181 - PP199
1PP201 - PP205
1PP221
1PP231 - PP243
1PP281 - PP286
1PP301 - PP305
1PP351 - PP353
1PP376 - PP384
1PP391 - PP393
1PP401 - PP440
1PP471 - PP475
1PP501 - PP522
1PP631 - PP634
1PP651 - PP652
1PP671 - PP699
1PP701 - PP733
1PP771 - PP779
1PP801 - PP808
1PP821 - PP827
1PP831 - PP848
1PP851 - PP852
1PP861 - PP877
1PP891 - PP899
1PP901 - PP936
1PP946 - PP948
1PP951 - PP952
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GroupVariable Number
1PP961 - PP967
1PP981 - PP991
1PP993
1PQ001 - PQ016
1PQ026 - PQ041
1PQ051 - PQ092
1PQ101 - PQ199
1PQ201 - PQ202
1PQ221 - PQ237
1PQ241 - PQ243
1PQ251 - PQ267
1PQ281 - PQ299
1PQ301 - PQ307
1PQ331 - PQ332
1PQ341 - PQ348
1PQ361 - PQ373
1PQ391 - PQ395
1PQ401 - PQ418
1PQ421
1PQ431 - PQ438
1PQ447 - PQ448
1PQ451
1PQ454
1PQ471 - PQ475
1PQ479 - PQ481
1PQ486 - PQ487
1PQ491 - PQ493
1PQ771 - PQ772
1PQ791 - PQ793
1PQ801 - PQ805
1PQ931 - PQ935
1PQ951
1PQ971 - PQ997
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GroupVariable Number
1PR001 - PR017
1PR021 - PR034
1PR041 - PR045
1PR061 - PR072
1PR077 - PR082
1PR091 - PR092
1PR096
1PR101
1PR121 - PR122
1PR131 - PR132
1PR141 - PR143
1PR161 - PR172
1PR181
1PS601 - PS631
1PS636 - PS638
1PS641 - PS644
1PS651 - PS657
1PS666 - PS669
1PS691 - PS692
1PS701 - PS706
1PS751 - PS799
1PS811
1PS836 - PS837
1PS841 - PS846
1PS851 - PS852
1PS856
1PS861 - PS863
1PS866 - PS868
1PS871 - PS874
1PS896 - PS897
1PS901 - PS941
1PS956 - PS957
1PS961 - PS963
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GroupVariable Number
1PS971 - PS978
1PT001 - PT015
1PT021 - PT031
1PT041 - PT064
1PT101 - PT105
1PT121 - PT138
1PT146 - PT148
1PT161 - PT170
1PT181 - PT188
1PT211 - PT220
1PT295
1PT301 - PT309
1PT331 - PT360
1PT381 - PT399
1PT401 - PT438
1PT501 - PT517
1PT561 - PT565
1PT581 - PT586
1PT611 - PT621
1PT641 - PT644
1PT651 - PT656
1PT671 - PT672
1PT681 - PT685
1PT701 - PT703
1PT716 - PT717
1PT721 - PT725
1PT801 - PT834
1PT851 - PT854
1PT871 - PT886
1PT901 - PT930
1PT971 - PT973
1PT981 - PT985
1PT996
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GroupVariable Number
1PU001 - PU025
1PU301
1PU311 - 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
2PW301 - PW327
2PW401 - PW408
2PW411 - PW418
2PW421 - PW424
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GroupVariable Number
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
2. Spares Affected
None.
B. Concurrent Requirements
None.
C. Reason
This service bulletin gives instructions to inspect the frame inner chord below stringer S-11 for any
crack. The frame for 737-300/-500 is at BS 616 forward of the emergency exit, and for 737-400 it is at
BS 578 forward of the forward emergency exit on both sides of the airplane. An operator of a 737-300
reported a crack of approximately 1.00 inch in the BS 616 frame inboard chord during Supplemental
Structural Inspection Document (SSID) inspections. The crack was located at the lowest fastener hole
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### Page 16

of the inboard chord inboard strap below stringer S-11R. The airplane had 75,584 total flight hours and
63,570 total flight cycles. Cracking in the inboard chord is the result of fatigue caused by cyclic
pressurization of the fuselage. If not found and repaired, a crack in the inboard chord of the noted
frames below S-11L or S-11R could result in structural failure of the frame and possible rapid
decompression.
Boeing Fleet Team Digest (FTD) 737 FTD 53-15008 is related to this service bulletin.
D. Description
Group 1:
Do PART 1: DETAILED INSPECTION AND HFEC INSPECTION for any crack in the BS 616 frame
inboard chord below S-11L and S-11R at the lowest fastener of the inboard strap. If no crack is found,
repeat PART 1: DETAILED INSPECTION AND HFEC INSPECTION at the repeat interval in Paragraph
1.E., Compliance. If any crack is found, contact The Boeing Company for repair instructions and do
the repair.
Group 2:
Do PART 1: DETAILED INSPECTION AND HFEC INSPECTION for any crack in the BS 578 frame
inboard chord below S-11L and S-11R at the lowest fastener of the inboard strap. If no crack is found,
repeat PART 1: DETAILED INSPECTION AND HFEC INSPECTION at the repeat interval in Paragraph
1.E., Compliance. If any crack is found, contact The Boeing Company for repair instructions and do
the repair.
The work in this service bulletin is done in the maintenance zone(s) given below.
Group 1:
Affected Maintenance Zones
ZoneModel
107737-300, 737-500
Group 2:
Affected Maintenance Zones
ZoneModel
107737-400
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.
A Logic diagram showing compliance tasks and compliance times is included as an aid in APPENDIX
A.
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### Page 17

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.
Do the required actions in accordance with Paragraph 3. Accomplishment Instructions.
Table 1: Detailed Inspection and HFEC Inspection for Any Crack at the Frame Inboard Chord, Forward
of the Emergency Exit Opening, Left and Right Side
Repeat Interval
(Not to Exceed)
Compliance Time (Whichever
Occurs Later)
ActionCondition
-Within 4,500
flight cycles after
the original issue
date of this Ser-
vice Bulletin.
Before 50,000
total flight cy-
cles.
Do PART 1: DETAILED IN-
SPECTION AND HFEC IN-
SPECTION for any crack.
(a)
All Airplanes
-Before further flight.ACTION 1:CONDITION 1:
Contact The Boeing Compa-
ny for repair instructions and
do the repair.
ANY CRACK FOUND
6,000 flight cycles.-ACTION 2:
Repeat PART 1: DETAILED
INSPECTION AND HFEC
INSPECTION for any crack
at unrepaired areas.
(a)
6,000 flight cycles.-Repeat PART 1: DETAILED
INSPECTION AND HFEC
INSPECTION for any crack.
CONDITION 2:
NO CRACK FOUND
(a)
(a) It is not necessary to do PART 1 inspections in areas where an existing repair covers the affected inspec-
tion area provided:
1. The repair is the corrective action to the crack condition identified in this service bulletin, AND
2. The installed repair was approved by the Boeing Organization Designation Authorization (ODA)
via an FAA Form 8100-9.
F. Approval
This service bulletin was examined by the Federal Aviation Administration (FAA). The changes specified
in this service bulletin comply with the applicable regulations and are FAA approved, as well as European
Aviation Safety Agency (EASA)/Joint Aviation Authorities (JAA) approved for all EASA/JAA approved
airplanes listed in the service bulletin effectivity. This service bulletin and its approval were based on
the airplane in its original Boeing delivery configuration or as modified by other approved Boeing
changes.
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### Page 18

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
Group 1:
Elapsed HoursTask HoursNumber of PersonsTask
1.503.002Open Access
0.650.651Figure 1
0.650.651Figure 2
1.503.002Close Access
4.307.30TOTAL FOR EACH AIRPLANE
Group 2:
Elapsed HoursTask HoursNumber of PersonsTask
1.503.002Open Access
0.650.651Figure 3
0.650.651Figure 4
1.503.002Close Access
4.307.30TOTAL FOR EACH AIRPLANE
H. Weight and Balance Changes
None.
I. Electrical Load Data
Not changed.
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### Page 19

J. References
1. Existing Data:
a. Boeing Service Letter 737-SL-51-042
b. Service Bulletin Index D6-19567
c. 737 Fleet Team Digest (FTD) 53-15008
d. 737 Non-Destructive Testing (NDT) Manual Part 6, 51-00-00
e. 737-300/400/500 Aircraft Maintenance Manual (AMM) 25-21-39, 25-21-46, 25-22-00
2. Data Supplied with this Service Bulletin:
None.
3. Installation Drawings Used in the Preparation of this Service Bulletin:
TitleDrawing Number
FRAME INSTALLATION - EMERGENCY ESCAPE HATCH BODY
STATION 578
65C32755
FRAME INSTL-EMERGENCY ESCAPE HATCH, BODY STA 61665-46539
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 does not affect FCS, therefore DTIs are not 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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### Page 20

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BLANK PAGE

### Page 21

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 inspection 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 22

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### Page 23

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).
4. 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.
5. 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.
6. Boeing Service Letter 737-SL-51-042, 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.
7. Refer to APPENDIX A for logic diagram(s). Logic diagrams are provided as an aid
only. Information contained in Paragraph 1.E., Compliance is the primary source for
compliance times. Information in Paragraph 3.B., Work Instructions is the primary
source for tasks required for compliance.
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### Page 24

8. 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.
9. 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.
10. Where the work instructions include installation of a kept part, a new or serviceable
part with the same part number can be installed as an alternative to the kept part.
11. Use of colors in Figures is based on guidance from the ATA e-Business Program
(ATA) iSpec 2200.
12. 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.
13. The compliance times for the actions in Paragraph 3.B., WORK INSTRUCTIONS
are in Paragraph 1.E., Compliance.
14. Some steps in the Work Instructions are labeled as Required for Compliance (RC).
If this service bulletin is mandated by an Airworthiness Directive (AD), then the steps
labeled as RC, including sub-steps under an RC step and any figures identified in
an RC step, must be done to comply with the AD. An Alternative Method of
Compliance (AMOC) is required for any deviations to RC steps, including sub-steps
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:
Remove and keep Passenger Seats, Sidewall Panel and Insulation to get access to the BS 616
frame. Refer to 737-300/400/500 AMM 25-22-00, 737-300/400/500 AMM 25-21-46 and
737-300/400/500 AMM 25-21-39 as accepted procedures.
Group 2:
Remove and keep Passenger Seats, Sidewall Panel and Insulation to get access to the BS 578
frame. Refer to 737-300/400/500 AMM 25-22-00, 737-300/400/500 AMM 25-21-46 and
737-300/400/500 AMM 25-21-39 as accepted procedures.
2. RC - Do PART 1: DETAILED INSPECTION AND HFEC INSPECTION OF INBOARD CHORD for
any crack.
NOTE: It is not necessary to do PART 1 inspections in areas where an existing repair covers the
affected inspection area provided:
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### Page 25

1. The repair is the corrective action to the crack condition identified in this service
bulletin, AND
2. The installed repair was approved by the Boeing Organization Designation
Authorization (ODA) via an FAA Form 8100-9.
a. CONDITION 1: ANY CRACK FOUND.
(1) ACTION 1: Contact The Boeing Company for repair instructions and do the repair.
(2) ACTION 2: Repeat PART 1: DETAILED INSPECTION AND HFEC INSPECTION for any
crack, at unrepaired areas at the repeat interval in Paragraph 1.E., Compliance.
NOTE: It is not necessary to do PART 1 inspections in areas where an existing repair
covers the affected inspection area provided:
1. The repair is the corrective action to the crack condition identified in
this service bulletin, AND
2. The installed repair was approved by the Boeing Organization
Designation Authorization (ODA) via an FAA Form 8100-9.
b. CONDITION 2: NO CRACK FOUND.
(1) Repeat PART 1: DETAILED INSPECTION AND HFEC INSPECTION for any crack at
the repeat interval in Paragraph 1.E., Compliance.
NOTE: It is not necessary to do PART 1 inspections in areas where an existing repair
covers the affected inspection area provided:
1. The repair is the corrective action to the crack condition identified in
this service bulletin, AND
2. The installed repair was approved by the Boeing Organization
Designation Authorization (ODA) via an FAA Form 8100-9.
3. Group 1:
Install kept Insulation, Sidewall Panel and Passenger Seats removed to get access to the BS 616
frame. Refer to 737-300/400/500 AMM 25-21-39, 737-300/400/500 AMM 25-21-46 and
737-300/400/500 AMM 25-22-00 as accepted procedures.
Group 2:
Install kept Insulation, Sidewall Panel and Passenger Seats removed to get access to the BS 578
frame. Refer to 737-300/400/500 AMM 25-21-39, 737-300/400/500 AMM 25-21-46 and
737-300/400/500 AMM 25-22-00 as accepted procedures.
4. Put the airplane back to a serviceable condition.
PART 1: DETAILED INSPECTION AND HFEC INSPECTION OF INBOARD CHORD
1. Group 1:
Do a Detailed Inspection and High Frequency Eddy Current (HFEC) Inspection for any crack in
accordance with FIGURE 1 (left side) and FIGURE 2 (right side).
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### Page 26

Group 2:
Do a Detailed Inspection and High Frequency Eddy Current (HFEC) Inspection for any crack in
accordance with FIGURE 3 (left side) and FIGURE 4 (right side).
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### Page 27 (OCR)

BOEING SERVICE BULLETIN 737-53A1366
ALERT  ALERT
This Figure applies only to: Group 1.
STA
597
STA  616  S-9L
STA  • S-10L
639
_ S-11L
STA
663.75
- S-13L
- S-14L
— S-15L
737-300 AND 737-500
EMERGENCY EXIT
2477176
FIGURE 1: DETAILED INSPECTION AND HFEC INSPECTION OF LEFT SIDE BS 616 FRAME INBOARD
CHORD
(SHEET 1 OF 3)
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### Page 28 (OCR)

BOEING SERVICE BULLETIN 737-53A1366
ALERT  ALERT
INBOARD STRAP
- STRINGER 11
TYPICAL CRACK
• FRAME WEB
INBOARD FLANGE OF
FRAME INBOARD CHORD •
INBD
INSPECTION AREA
STA 616 FRAME INBOARD CHORD
VIEW LOOKING AFT
LEFT SIDE
2477182
FIGURE 1: DETAILED INSPECTION AND HFEC INSPECTION OF LEFT SIDE BS 616 FRAME INBOARD
CHORD
(SHEET 2 OF 3)
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### Page 29

The step numbers shown below agree with the numbers shown in the circle symbols in the figure.
More
Data
LocationNameTaskStep
(a) (b)Outboard side of Inboard flange around
the fastener shown
BS 616 Frame
Inboard Chord
Inspect1
(a) Do a Detailed Inspection for any crack.
(b) Do HFEC inspection for any crack, in accordance with 737 NDT Manual Part 6,
51-00-00, Procedure 4 or Procedure 23.
FIGURE 1: DETAILED INSPECTION AND HFEC INSPECTION OF LEFT SIDE BS 616 FRAME INBOARD
CHORD
(SHEET 3 OF 3)
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ALERTALERT

### Page 30 (OCR)

BOEING SERVICE BULLETIN 737-53A1366
ALERT  ALERT
This Figure applies only to: Group 1.
STA
597
5-9R -  STA  616
S-10R  STA
639
S-11R .
SIA
663.75
S-13R
S-14R \
S-15R ~
010100101010101
737-300 AND 737-500
EMERGENCY EXIT
2477184
FIGURE 2: DETAILED INSPECTION AND HFEC INSPECTION OF RIGHT SIDE BS 616 FRAME INBOARD
CHORD
(SHEET 1 OF 3)
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### Page 31 (OCR)

BOEING SERVICE BULLETIN 737-53A1366
ALERT  ALERT
INBOARD STRAP
STRINGER 11 -
• TYPICAL CRACK
FRAME WEB
INBOARD FLANGE OF
FRAME INBOARD CHORD
INBD
INSPECTION AREA
STA 616 FRAME INBOARD CHORD
VIEW LOOKING AFT
RIGHT SIDE
2477185
FIGURE 2: DETAILED INSPECTION AND HFEC INSPECTION OF RIGHT SIDE BS 616 FRAME INBOARD
CHORD
(SHEET 2 OF 3)
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### Page 32

The step numbers shown below agree with the numbers shown in the circle symbols in the figure.
More
Data
LocationNameTaskStep
(a) (b)Outboard side of Inboard flange around
the fastener shown
BS 616 Frame
Inboard Chord
Inspect1
(a) Do a Detailed Inspection for any crack.
(b) Do HFEC inspection for any crack, in accordance with 737 NDT Manual Part 6,
51-00-00, Procedure 4 or Procedure 23.
FIGURE 2: DETAILED INSPECTION AND HFEC INSPECTION OF RIGHT SIDE BS 616 FRAME INBOARD
CHORD
(SHEET 3 OF 3)
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BOEING SERVICE BULLETIN 737-53A1366
ALERTALERT

### Page 33 (OCR)

BOEING SERVICE BULLETIN 737-53A1366
ALERT  ALERT
This Figure applies only to: Group 2.
STA
559
STA  - S-91
578
STA  →—S-†OL
601
SIA  S-11L
616
STA
639  S-13L
STA  S-14L
663.75
/ S-15L
ODOUC
737-400
EMERGENCY EXIT
2479027
FIGURE 3: DETAILED INSPECTION AND HFEC INSPECTION OF LEFT SIDE BS 578 FRAME INBOARD
CHORD
(SHEET 1 OF 3)
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### Page 34 (OCR)

BOEING SERVICE BULLETIN 737-53A1366
ALERT  ALERT
INBOARD STRAP
STRINGER 11
FRAME WEB
TYPICAL CRACK
INBOARD FLANGE OF
FRAME INBOARD CHORD •
- INBD
INSPECTION AREA
STA 578 FRAME INBOARD CHORD
VIEW LOOKING AFT
LEFT SIDE
2479028
FIGURE 3: DETAILED INSPECTION AND HFEC INSPECTION OF LEFT SIDE BS 578 FRAME INBOARD
CHORD
(SHEET 2 OF 3)
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### Page 35

The step numbers shown below agree with the numbers shown in the circle symbols in the figure.
More
Data
LocationNameTaskStep
(a) (b)Outboard side of Inboard flange around
the fastener shown
BS 578 Frame
Inboard Chord
Inspect1
(a) Do a Detailed Inspection for any crack.
(b) Do HFEC inspection for any crack, in accordance with 737 NDT Manual Part 6,
51-00-00, Procedure 4 or Procedure 23.
FIGURE 3: DETAILED INSPECTION AND HFEC INSPECTION OF LEFT SIDE BS 578 FRAME INBOARD
CHORD
(SHEET 3 OF 3)
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BOEING SERVICE BULLETIN 737-53A1366
ALERTALERT

### Page 36 (OCR)

BOEING SERVICE BULLETIN 737-53A1366
ALERT  ALERT
This Figure applies only to: Group 2.
STA
559
S-9R .  STA
578
S-10R _
STA
601
S-11R .
STA
616
STA
S-13R -  639
S-14R _  STA
663.75
S-15R.
737-400
EMERGENCY EXIT
2479029
FIGURE 4: DETAILED INSPECTION AND HFEC INSPECTION OF RIGHT SIDE BS 578 FRAME INBOARD
CHORD
(SHEET 1 OF 3)
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### Page 37 (OCR)

BOEING SERVICE BULLETIN 737-53A1366
ALERT  ALERT
INBOARD STRAP
STRINGER 11
FRAME WEB
• TYPICAL CRACK
INBOARD FLANGE OF
FRAME INBOARD CHORD
INBD
INSPECTION AREA
STA 578 FRAME INBOARD CHORD
VIEW LOOKING AFT
RIGHT SIDE
2479042
FIGURE 4: DETAILED INSPECTION AND HFEC INSPECTION OF RIGHT SIDE BS 578 FRAME INBOARD
CHORD
(SHEET 2 OF 3)
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### Page 38

The step numbers shown below agree with the numbers shown in the circle symbols in the figure.
More
Data
LocationNameTaskStep
(a) (b)Outboard side of Inboard flange around
the fastener shown
BS 578 Frame
Inboard Chord
Inspect1
(a) Do a Detailed Inspection for any crack.
(b) Do HFEC inspection for any crack, in accordance with 737 NDT Manual Part 6,
51-00-00, Procedure 4 or Procedure 23.
FIGURE 4: DETAILED INSPECTION AND HFEC INSPECTION OF RIGHT SIDE BS 578 FRAME INBOARD
CHORD
(SHEET 3 OF 3)
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### Page 39

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 AND HFEC INSPECTION OF INBOARD CHORD
for any crack.
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
It is not necessary to do PART 1 inspections in areas where an existing repair
covers the affected inspection area provided:
(a)
1. The repair is the corrective action to the crack condition identified in
this service bulletin, AND
2. The installed repair was approved by the Boeing Organization Des-
ignation Authorization (ODA) via an FAA Form 8100-9.
APPENDIX A:  LOGIC DIAGRAM FOR PARAGRAPH 1.E. COMPLIANCE: TABLE 1: DETAILED INSPECTION
AND HFEC INSPECTION FOR ANY CRACK AT THE FRAME INBOARD CHORD, FORWARD OF THE
EMERGENCY EXIT OPENING, LEFT AND RIGHT SIDE
(SHEET 1 OF 2)
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ALERTALERT

### Page 40 (OCR)

BOEING SERVICE BULLETIN 737-53A1366
ALERT  ALERT
WHICHEVER OCCURS LATER
WITHIN 4,500 FLIGHT
CYCLES AFTER THE
BEFORE 50,000 TOTAL  FLIGHT CYCLES  ORIGINAL ISSUE DATE  OF THIS SERVICE
BULLETIN
DO PART 1
(a)
CONDITION 1  CONDITION 2
BEFORE FURTHER
FLIGHT  NOT TO EXCEED 6,000
FLIGHT CYCLES
ACTION 1:
CONTACT THE BOEING
COMPANY FOR REPAIR
INSTRUCTIONS AND DO
THE REPAIR  REPEAT PART 1
NOT TO EXCEED 6,000
FLIGHT CYCLES
ACTION 2:
REPEAT PART 1 AT THE
UNREPAIRED AREAS
(a)  2477215
APPENDIX A: LOGIC DIAGRAM FOR PARAGRAPH 1.E. COMPLIANCE: TABLE 1: DETAILED INSPECTION
AND HFEC INSPECTION FOR ANY CRACK AT THE FRAME INBOARD CHORD, FORWARD OF THE
EMERGENCY EXIT OPENING, LEFT AND RIGHT SIDE
(SHEET 2 OF 2)
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---
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