# Boeing Alert Service Bulletin 737-53A1323: No revision named

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- Document: [Boeing Alert Service Bulletin 737-53A1323](https://openairdocs.org/service-documents/boeing/737-53a1323.md)
- Title as filed: U.S. DOT/FAA - Service Bulletin
- Pages: 321
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### Page 1

Commercial 
Airplanes
737
Service Bulletin
ALERT
Number: 737-53A1323
Original Issue: December 06, 2013
ATA System: 5311 5331 2158
SUBJECT: FUSELAGE - Frames - Cracking of Frames at STA 328 Between Stringers S-20R to
S-21R, STA 360 Between Stringers S-19R to S-21R, and STA 380 Between Stringers
S-18R to S-20R, and Missing Strap on Frame at STA 312 - Inspection, Modification,
and Repair
Export of this technology is controlled under the United States Export Administration Regulations (EAR) (15
CFR 300-774). An export license may be required before it is used for development, production or use by foreign
persons from specific countries. The controller of this data has the individual responsibility to abide by all export
laws.
9E991ECCN:
BOEING PROPRIETARY, CONFIDENTIAL AND/OR TRADE SECRET
Copyright © 2013 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Unpublished Work.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
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Table of Contents
Summary ...................................................... 5
1. PLANNING INFORMATION ........................................ 1 3
A. Effectivity ............................................... 1 3
1. Airplanes ............................................ 1 3
2. Spares Affected ........................................ 2 8
B. Concurrent Requirements ...................................... 2 8
C. Reason ................................................ 2 8
D. Description .............................................. 2 9
E. Compliance .............................................. 3 2
F. Approval ............................................... 6 0
G. Manpower .............................................. 6 1
H. Weight and Balance Changes .................................... 7 1
I. Electrical Load Data ......................................... 7 1
J. References .............................................. 7 1
1. Existing Data: ......................................... 7 1
2. Data Supplied with this Service Bulletin: ........................... 7 2
3. Installation Drawings Used in the Preparation of this Service Bulletin: ........... 7 2
K. Publications Affected ........................................ 7 2
L. Interchangeability and Intermixability of Parts ........................... 7 3
M. Software Accomplishment Summary ................................ 7 3
2. MATERIAL INFORMATION ........................................ 7 5
A. Material - Price and Availability ................................... 7 5
B. Industry Support Information .................................... 7 5
C. Parts Necessary for Each Airplane ................................. 7 5
1. Kits/Parts ............................................ 7 5
2. Parts and Materials Supplied by the Operator ........................ 7 5
3. Parts Modified and Reidentified ................................ 8 0
4. Parts Removed and Not Replaced .............................. 8 0
D. Parts Necessary to Change Spares ................................. 8 0
E. Special Tooling - Price and Availability ............................... 8 0
F. Special Tooling Necessary to do this Service Bulletin ....................... 8 0
3. ACCOMPLISHMENT INSTRUCTIONS .................................. 8 1
A. GENERAL INFORMATION ..................................... 8 1
B. WORK INSTRUCTIONS ....................................... 8 2
FIGURE 1: OPEN ACCESS [Group 2-5] .................................. 9 8
FIGURE 2: OPEN ACCESS [Group 6-7] ................................. 1 0 2
FIGURE 3: GENERAL VISUAL INSPECTION OF THE FRAME AT STA 312 TO MAKE SURE STRAP IS
INSTALLED [Group 2-7] ................................... 1 0 4
FIGURE 4: DETAILED INSPECTION OF THE FRAME AT STA 328 [Group 2-7] ........... 1 0 8
FIGURE 5: HFEC INSPECTION OF THE FRAME AT STA 328 [Group 2-7] .............. 1 1 4
FIGURE 6: DETAILED INSPECTION OF THE FRAME AT STA 312 [Group 2-7] ........... 1 2 1
FIGURE 7: DETAILED INSPECTION OF THE FRAME AT STA 344 [Group 2-7] ........... 1 2 5
FIGURE 8: DETAILED INSPECTION OF THE FRAME AT STA 360 [Group 2-5] ........... 1 2 9
FIGURE 9: HFEC INSPECTION OF THE FRAME AT STA 360 [Group 2-5] .............. 1 3 5
FIGURE 10: DETAILED INSPECTION OF THE FRAME AT STA 380 [Group 2, 4] ........... 1 4 3
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FIGURE 11: HFEC INSPECTION OF THE FRAME AT STA 380 [Group 2, 4] .............. 1 4 8
FIGURE 12: DETAILED INSPECTION OF THE FRAME AT STA 380 [Group 3, 5] ........... 1 5 3
FIGURE 13: HFEC INSPECTION OF THE FRAME AT STA 380 [Group 3, 5] .............. 1 5 8
FIGURE 14: DETAILED AND EDDY CURRENT INSPECTIONS OF THE FUSELAGE SKIN [Group 2-3] . 163
FIGURE 15: DETAILED AND EDDY CURRENT INSPECTIONS OF THE FUSELAGE SKIN [Group 4-5] . 165
FIGURE 16: DETAILED AND EDDY CURRENT INSPECTIONS OF THE FUSELAGE SKIN [Group 6] . 167
FIGURE 17: PRE-MODIFICATION INSPECTION - TOOL HOLE - FRAME AT STA 360 [Group 2-5] . 169
FIGURE 18: MODIFICATION - TOOL HOLE - FRAME AT STA 360 [Group 2-5] ............ 1 7 3
FIGURE 19: PRE-MODIFICATION INSPECTION - INSULATION BLANKET STUD HOLE - FRAME AT STA
360 [Group 2-5] ........................................ 1 7 8
FIGURE 20: MODIFICATION - INSULATION BLANKET STUD HOLE - FRAME AT STA 360 [Group 2-5]
................................................. 1 8 2
FIGURE 21: PRE-MODIFICATION INSPECTION - END FASTENERS IN THE DOUBLER - FRAME AT STA
360 [Group 2-5] ........................................ 1 8 7
FIGURE 22: MODIFICATION - END FASTENERS IN THE DOUBLER - FRAME AT STA 360 [Group 2-5]
................................................. 1 9 4
FIGURE 23: PRE-REPAIR INSPECTION - REMOVAL OF PARTS AND INSPECTION OF FASTENER HOLES
- FRAME AT STA 328 [Group 2-7] .............................. 2 0 2
FIGURE 24: MAKE THE REPAIR PARTS - FRAME AT STA 328 [Group 2-6] .............. 2 1 6
FIGURE 25: REPAIR - FRAME AT STA 328 [Group 2-6] ......................... 2 3 6
FIGURE 26: MAKE THE REPAIR PARTS - FRAME AT STA 328 [Group 7] ............... 2 5 9
FIGURE 27: REPAIR - FRAME AT STA 328 [Group 7] .......................... 2 7 9
FIGURE 28: POST-MODIFICATION DAMAGE TOLERANCE INSPECTION - FRAME AT STA 360 [Group
2-5] ............................................... 3 0 2
FIGURE 29: POST-REPAIR DAMAGE TOLERANCE INSPECTION - FRAME AT STA 328 [Group 2-7] . 308
FIGURE 30: CLOSE ACCESS [Group 2-5] ................................ 3 1 3
FIGURE 31: CLOSE ACCESS [Group 6-7] ................................ 3 1 6
APPENDIX A: REMOVAL AND INSTALLATION OF THE EQUIPMENT COOLING PLENUM FOR ADDITIONAL
ACCESS [Group 2-5] ..................................... 3 1 8
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Commercial 
Airplanes
737
Service Bulletin
ALERT
SummaryNumber: 737-53A1323Original Issue: December 06, 2013
ATA System: 5311 5331 2158
SUBJECT: FUSELAGE - Frames - Cracking of Frames at STA 328 Between Stringers S-20R to
S-21R, STA 360 Between Stringers S-19R to S-21R, and STA 380 Between Stringers
S-18R to S-20R, and Missing Strap on Frame at STA 312 - Inspection, Modification,
and Repair
THIS BULLETIN IS SENT TO THE OPERATORS OF RECORD OF THE AIRPLANES SHOWN IN PARAGRAPH
1.A., EFFECTIVITY. IF AN AIRPLANE HAS BEEN LEASED OR SOLD, SEND THIS SERVICE BULLETIN TO
THE NEW OPERATOR. IF APPLICABLE SPARES HAVE BEEN SOLD, SEND THIS SERVICE BULLETIN TO
THE NEW OWNER.
CONCURRENT REQUIREMENTS
None.
BACKGROUND
This service bulletin is sent to inspect frames at STA 328 between stringers S-20R to S-21R, STA 360 between
stringers S-19R to S-21R, and STA 380 between stringers S-18R to S-22R for cracking. Operators have sent
in reports of cracking in these frames. Also, this service bulletin inspects adjacent frames at STA 312 between
stringers S-19R to S-22R and STA 344 between stringers S-18R to S-22R. In addition, this service bulletin
inspects the frame at STA 312 for a missing strap adjacent to stringer S-22R. A missing strap can make the
frame crack. If cracks in the frames are not detected and repaired, they can grow until the frames sever. Continued
operation of the airplane with multiple adjacent severed frames can result in uncontrolled decompression of the
airplane, and also, the combination of a severed frame and fuselage skin chem mill cracks in this area can result
in uncontrolled decompression of the airplane.
Refer to Boeing Service Bulletin 737-53A1210 for reports of fuselage skin chem mill cracks.
Accomplishment of the inspections in this service bulletin will make sure that cracks in the frames at STA 328
between stringers S-20R to S-21R, STA 360 between stringers S-19R to S-21R, and STA 380 between stringer
S-18R to S-22R are found and repaired. Also, accomplishment of the inspections in this service bulletin will
make sure that cracks in adjacent frames at STA 312 between stringers S-19R to S-22R and STA 344 between
stringers S-19R to S-22R are found and repaired. If cracks in the frames are found and repaired, then the effect
of a severed frame can not interact with the effect of fuselage skin cracks. In addition, accomplishment of the
inspection in this service bulletin will ensure that the strap adjacent to stringer S-22R on the frame at STA 312
is installed.
One operator of a 737-300 airplane sent a report of a crack in the frame at STA 328 and a crack that severed
the frame at STA 360 on the right side of the same airplane with 59,756 flight cycles. The crack in the frame at
STA 328 was between stringers S-20R to S-21R. The crack length was not reported. The crack in the frame at
STA 360 was between stringers S-19R to S-20R. The frame web and the failsafe chord were completely severed.
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Operators of 737-200, 737-300, and 737-500 airplanes sent ten reports of cracks in the frame at STA 328
between stringers S-20R and S-21R on ten airplanes with 43,581 to 73,655 flight cycles. Cracks were in the
frame web at an open tool hole, in the frame web at the end fastener in the inner chord, and in the frame web
notch. The cracks were from 0.3 inch to 3.0 inches long.
Operators of 737-200 and 737-300 airplanes sent fourteen reports of cracks in the frame at STA 360 between
stringers S-19R and S-21R on fourteen airplanes with 42,183 to 66,588 flight cycles. Cracks were in the frame
web at an open tool hole, in the frame web at an insulation blanket stud hole, in the frame web at an end fastener
in the doubler, and in the inner flange at the end fastener in the doubler. The cracks were from 2.5 inches long
to cracks that severed the frame web and fail-safe chord.
An operator of a 737-300 airplane sent one report of three cracks in the frame at STA 380 between stringers
S-18R and S-20R on one airplane with 32,218 flight cycles. Cracks were in the frame inner flange at fasteners
common to the bulkhead support angle. One of the three cracks was also in the doubler. Crack lengths were
not reported.
An operator of a 737-400 airplane sent in one report of a strap that was not installed on the frame at STA 312
adjacent to stringer S-22R on one airplane with 24,037 flight cycles. Investigation of the drawings revealed that
this was an incorrect frame configuration and that the strap should have been installed. The incorrect frame
configuration was discovered during a repair of the STA 312 frame because of ground damage. There was no
report of cracks caused by the incorrect frame configuration.
Boeing Fleet Team Digest (FTD) 737 FTD 53-10001 is related to this service bulletin.
Boeing Service Related Problem (SRP) 737-SRP-53-0359 is related to this service bulletin.
The table below 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., ComplianceYesAD Related
Paragraph 1.H., Weight and Balance ChangesYesWeight 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
YesOperator Supplied Material
Paragraph 2.F., Special Tooling Necessary to
do this Service Bulletin
NoSpecial Tooling Required
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ACTION
Group 1:
On Group 1 airplanes, contact Boeing to get instructions for the inspection and/or repair for this service bulletin,
and do the work instructed by Boeing.
Group 2-5:
On the frame at STA 312, do a general visual inspection of the frame to make sure that the strap adjacent to
stringer S-22R is installed. If the strap is installed, then no more work is necessary to make sure that the strap
is installed. If the strap is not installed, then before further flight, repair the frame at STA 312.
On the frame at STA 328, do a detailed inspection between stringers S-20R to S-21R for cracking or a severed
frame web. Do an open hole High Frequency Eddy Current (HFEC) inspection of a tool hole in the frame web
for cracking, a surface HFEC inspection of the frame web around the end fastener in the inner chord for cracking,
and a surface HFEC inspection of the frame web notch for cracking. If no crack is found, then continue to do
repeat inspections. If any crack is found, then before further flight, repair the frame. If a severed frame web is
found, then before further flight, repair the frame, do a detailed inspection of the frame at STA 312 between
stringers S-19R to S-22R for cracking, do a detailed inspection of the frame at STA 344 between stringers S-18R
to S-22R for cracking, and do detailed and eddy current inspections of the fuselage skin for cracking. If no crack
is found, then no more work is necessary on the frame at STA 312, but continue to do repeat inspections of the
frame at STA 344. If any crack is found on the frame at STA 312, or on the frame at STA 344, then before further
flight, repair the frame. If any crack is found in the fuselage skin, then before further flight, repair the skin. If you
do the repair of the frame at STA 328 in accordance with this service bulletin, then you can stop repeat inspections
of the frame at STA 328. Do post-repair damage tolerance inspections of the repair of the frame at STA 328.
On the frame at STA 344, do a detailed inspection between stringers S-18R to S-22R for cracking. If no crack
is found, then continue to do repeat inspections. If any crack is found, then before further flight, repair the frame
at STA 344. If you do the repair of the frame at STA 328 in accordance with this service bulletin, and you do the
optional preventative modification to the frame at STA 360 in accordance with this service bulletin, then you can
stop repeat inspections of the frame at STA 344.
On the frame at STA 360, do a detailed inspection between stringers S-19R to S-21R for cracking or a severed
frame web. Do an open hole HFEC inspection of a tool hole in the frame web for cracking, an open hole HFEC
inspection of an insulation blanket stud hole in the frame web for cracking, a surface HFEC inspection of the
frame web around an end fastener in the doubler, and a surface HFEC inspection of the inner flange around
the end fastener in the doubler for cracking. If no crack is found, then continue to do repeat inspections. If any
crack is found, then before further flight, repair the frame at STA 360. If a severed frame web is found, then
before further flight, repair the frame at STA 360, do a detailed inspection of the frame at STA 344 between
stringers S-18R to S-22R for cracking, do a detailed inspection of the frame at STA 380 between stringers S-18R
to S-22R for cracking, and do detailed and eddy current inspections of the fuselage skin for cracking. If no crack
is found, then continue to do repeat inspections on the frame at STA 344, and the frame at STA 380. If any
crack is found in the frame at STA 344, or on the frame at STA 380, then before further flight, repair the frame.
If any crack is found in the fuselage skin, then before further flight, repair the skin. If you do the optional
preventative modification to the frame at STA 360 in accordance with this service bulletin, then you can stop
repeat inspections of the frame at STA 360. Do post-modification damage tolerance inspections of the modified
area of the frame at STA 360.
On the frame at STA 380, do a detailed inspection of the frame between stringers S-18R to S-22R for cracking
or a severed frame web. Do a surface HFEC inspection of the inner flange adjacent to fasteners common to the
bulkhead support angle in the frame at STA 380 for cracking. If no crack is found, then continue to do repeat
inspections. If any crack is found, then before further flight, repair the frame at STA 380. If a severed frame web
is found, then before further flight, repair the frame at STA 380 and inspect adjacent structure.
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On the fuselage skin adjacent to the frames at STA 328 and STA 360 inspected by this service bulletin, you can
do optional external detailed and eddy current inspections for cracking. If you do the optional inspections of the
fuselage skin, you can increase the repeat inspection intervals for the frames. If no crack is found in the fuselage
skin, then you must continue to do repeat inspections of the fuselage skin for cracking. If any crack is found,
then before further flight, repair the fuselage skin, do a detailed inspection of the frame at STA 328 between
stringers S-20R to S-21R for cracking, and do a detailed inspection of the frame at STA 360 between stringers
S-19R to S-21R for cracking. If any crack is found on the frame at STA 328, or on the frame at STA 360, then
before further flight, repair the frame. You must continue to do repeat inspections of the unrepaired area of the
fuselage skin for cracking. If you do a repair of the fuselage skin in accordance with this service bulletin, then
you can stop repeat inspections of the skin common to the repair. Do post-repair damage tolerance inspections
of the repair of the fuselage skin. If you do the repair of the frame at STA 328 in accordance with this service
bulletin, and you do the optional preventative modification to the frame at STA 360 in accordance with this
service bulletin, then you can stop repeat inspections of the fuselage skin in accordance with this service bulletin.
Refer to AMOC in Paragraph 1.F., Approval.
Group 6:
On the frame at STA 312, do a general visual inspection of the frame to make sure that the strap adjacent to
stringer S-22R is installed. If the strap is installed, then no more work is necessary to make sure that the strap
is installed. If the strap is not installed, then before further flight, repair the frame at STA 312.
On the frame at STA 328, do a detailed inspection between stringers S-20R to S-21R for cracking or a severed
frame web. Do an open hole High Frequency Eddy Current (HFEC) inspection of a tool hole in the frame web
for cracking, a surface HFEC inspection of the frame web around the end fastener in the inner chord for cracking,
and a surface HFEC inspection of the frame web notch for cracking. If no crack is found, then continue to do
repeat inspections. If any crack is found, then before further flight, repair the frame. If a severed frame web is
found, then before further flight, repair the frame, do a detailed inspection of the frame at STA 312 between
stringers S-19R to S-22R for cracking, do a detailed inspection of the frame at STA 344 between stringers S-18R
to S-22R for cracking, and do detailed and eddy current inspections of the fuselage skin for cracking. If no crack
is found, then no more work is necessary on the frame at STA 312, or on the frame at STA 344. If any crack is
found on the frame at STA 312, or on the frame at STA 344, then before further flight, repair the frame. If any
crack is found in the fuselage skin, then before further flight, repair the skin. If you do the repair of the frame at
STA 328 in accordance with this service bulletin, then you can stop repeat inspections of the frame at STA 328.
Do post-repair damage tolerance inspections of the repair of the frame at STA 328.
On the fuselage skin adjacent to the frame at STA 328 inspected by this service bulletin, you can do optional
external detailed and eddy current inspections for cracking. If you do the optional inspections of the fuselage
skin, then you can increase the repeat inspection interval for the frame. If no crack is found in the fuselage skin,
then you must continue to do repeat inspections of the fuselage skin. If any crack is found, then before further
flight, repair the fuselage skin and do a detailed inspection of the frame at STA 328 between stringers S-20R
to S-21R for cracking. If any crack is found on the frame at STA 328, then before further flight, repair the frame.
You must continue to do repeat inspections of the unrepaired area of the fuselage skin for cracking. If you do
skin repairs in accordance with this service bulletin, then you can stop repeat inspections of the skin common
to the repair. Do post-repair damage tolerance inspections of the repair of the fuselage skin. If you do the repair
of the frame at STA 328 in accordance with this service bulletin, then you can stop repeat inspections of the
fuselage skin in accordance with this service bulletin. Refer to AMOC in Paragraph 1.F., Approval.
Group 7:
On the frame at STA 312, do a general visual inspection of the frame to make sure that the strap adjacent to
stringer S-22R is installed. If the strap is installed, then no more work is necessary to make sure that the strap
is installed. If the strap is not installed, then before further flight, repair the frame at STA 312.
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On the frame at STA 328, do a detailed inspection between stringers S-20R to S-21R for cracking or a severed
frame web. Do an open hole High Frequency Eddy Current (HFEC) inspection of a tool hole in the frame web
for cracking, a surface HFEC inspection of the frame web around the end fastener in the inner chord for cracking,
and a surface HFEC inspection of the frame web notch for cracking. If no crack is found, then continue to do
repeat inspections. If any crack is found, then before further flight, repair the frame. If a severed frame web is
found, then before further flight, repair the frame, do a detailed inspection of the frame at STA 312 between
stringers S-19R to S-22R for cracking, and do a detailed inspection of the frame at STA 344 between stringers
S-18R to S-22R for cracking. If no crack is found, then no more work is necessary on the frame at STA 312, or
on the frame at STA 344. If any crack is found on the frame at STA 312, or on the frame at STA 344, then before
further flight, repair the frame. If you do the repair of the frame at STA 328 in accordance with this service bulletin,
then you can stop repeat inspections of the frame at STA 328. Do post-repair damage tolerance inspections of
the repair of the frame at STA 328.
EFFECTIVITY
737-100/200/200C/300/400/500 Airplanes. Refer to Paragraph1.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 configuration changes or inspection and/or modification
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.
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### Page 10 (OCR)

BOEING SERVICE BULLETIN 737-53A1323
ALERT  ALERT
IF SEVERED FRAME  DO DETAILED AND  DO DETAILED INSPECTION
WEB IS FOUND AT STA  HFEC INSPECTIONS  FOR CRACKS
328, THEN DO DETAILED  FOR CRACKS  GROUPS 2 THRU 5
INSPECTION OF STA 312  (GROUPS 2 THRU 7)  F SEVERED FRAME WEB IS
FRAME FOR CRACKS  FOUND AT STA 328, THEN DO
(GROUPS 2 THRU 7)  DETAILED INSPECTION OF
STA 344 FRAME FOR CRACKS
STA  312  IF SEVERED FRAME WEB IS  (GROUP 2 THRU 7)
FOUND AT STA 360, THEN DO
STA  DETAILED INSPECTION OF  DO DETAILED AND
328  HFEC INSPECTIONS
STA  STA 344 FRAME FOR CRACKS  (GROUP 2 THRU 5)  FOR CRACKS
344  (GROUP 2 THRU 5)
STA
360
STA  DO DETAILED AND
380  HFEC INSPECTIONS
FOR CRACKS
(GROUPS 2 THRU 5)
IF SEVERED FRAME
WEB IS FOUND AT
STA 360, THEN DO
DETAILED
INSPECTION OF STA
S-18R  380 FRAME FOR
CRACKS
S-19R  (GROUP 2 THRU 5)
S-20R
INSPECT FRAME TO  S-21R
MAKE SURE STRAP
IS INSTALLED
(GROUPS 2-7)  AREAS OF  REPORTED  - S-22R
CRACKING
2138257
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### Page 11 (OCR)

BOEING SERVICE BULLETIN 737-53A1323
ALERT  ALERT
SERVICE
DOOR  IF SEVERED FRAME WEB IS FOUND,
DO DETAILED AND EDDY CURRENT
INSPECTIONS OF THE SKIN.
(GROUPS 2-6)
YOU CAN DO OPTIONAL EXTERNAL
DETAILED AND EDDY CURRENT
INSPECTIONS OF THE FUSELAGE
SKIN TO INCREASE REPEAT
INSPECTION INTERVALS FOR THE
FRAMES.
(GROUPS 2-6)
DETAILED INSPECTION  DETAILED INSPECTION  DETAILED INSPECTION
AREA AND EDDY  AREA AND EDDY  AREA AND EDDY
CURRENT INSPECTION  CURRENT INSPECTION  CURRENT INSPECTION
ZONES FOR GROUPS 4  ZONES FOR GROUPS 2  / ZONES FOR GROUP 6
AND 5  AND 3
SERVICE
DOOR
S-17R
S-18R
S-19R
S-20R  J
S-21R
S-22R
STA  STA  STA  STA  STA  STA  STA
370  360  352  344  336  328  320
FWD  (FRAME)  (FRAME)  (FRAME)  EDDY CURRENT
INSPECTIONZONEL
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### Page 13

Commercial 
Airplanes
737
Service Bulletin
ALERT
Number: 737-53A1323
Original Issue: December 06, 2013
ATA System: 5311 5331 2158
SUBJECT: FUSELAGE - Frames - Cracking of Frames at STA 328 Between Stringers S-20R to
S-21R, STA 360 Between Stringers S-19R to S-21R, and STA 380 Between Stringers
S-18R to S-20R, and Missing Strap on Frame at STA 312 - Inspection, Modification,
and Repair
THIS BULLETIN IS SENT TO THE OPERATORS OF RECORD OF THE AIRPLANES SHOWN IN PARAGRAPH
1.A., EFFECTIVITY. IF AN AIRPLANE HAS BEEN LEASED OR SOLD, SEND THIS SERVICE BULLETIN TO
THE NEW OPERATOR. IF APPLICABLE SPARES HAVE BEEN SOLD, SEND THIS SERVICE BULLETIN TO
THE NEW OWNER.
1.    PLANNING INFORMATION
A. Effectivity
1. Airplanes
DESCRIPTIONCONFIGURATIONGROUP
737-100/200/200C airplanes, line numbers 1 to 291.-1
737-200/300/400 airplanes, between line numbers 292 and 1922.
These airplanes have the same skin panel configuration in the
inspection area as Group 3 airplanes, but do not have a hole for the
pitot line in the STA 380 frame.
-2
737-500 airplanes, between line numbers 1718 and 1921. These
airplanes have the same skin panel configuration in the inspection
area as Group 2 airplanes, but do have a hole for the pitot line in the
STA 380 frame.
-3
737-300/400 airplanes, between line numbers 1924 and 2565. These
airplanes have the same skin panel configuration in the inspection
area as Group 5 airplanes, but do not have a hole for the pitot line
in the STA 380 frame.
-4
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### Page 14

DESCRIPTIONCONFIGURATIONGROUP
737-500 airplanes, between line numbers 1923 and 2553. These
airplanes have the same skin panel configuration in the inspection
area as Group 4 airplanes, but do have a hole for the pitot line in the
STA 380 frame.
-5
737-200C airplanes, between line numbers 294 and 1113.-6
737-300/400/500 airplanes, line numbers 2566 to 3132.-7
Airplane Models:
737-100, 737-200, 737-200C, 737-300, 737-400, 737-500
GroupVariable Number
1PA001 - PA022
1PA099
1PA231 - PA232
1PC001 - PC005
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
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GroupVariable Number
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
4PJ301 - PJ302
4PJ551 - PJ552
7PJ553 - PJ561
7PJ601 - PJ615
7PJ811
7PJ816 - 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
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GroupVariable Number
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
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
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GroupVariable Number
2PK971 - PK974
2PL001 - PL028
2PL061
2PL081
2PL101 - PL113
2PL151
2PL171 - PL172
2PL201 - PL203
2PL221
2PL401 - PL417
2PL421
2PL441
2PL451 - PL456
2PL471
2PL491
2PL501 - PL506
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
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GroupVariable Number
2PM021 - PM023
2PM051 - PM066
2PM101 - PM119
2PM141 - PM142
2PM171
2PM181
2PM251 - PM255
2PM281 - PM283
2PM381 - PM392
4PM393 - PM399
4PM401 - PM417
4PM541 - PM547
7PM548 - PM550
4PM551 - PM564
2PN001 - PN002
2PN021 - PN043
2PN081 - PN086
2PN101 - PN117
2PN131 - PN163
2PN401 - PN420
2PN431 - PN433
2PN451 - PN456
2PN471 - PN474
2PN481
2PN491 - PN493
2PN501 - PN502
2PN511 - PN512
2PN521
2PP001 - PP054
2PP101 - PP148
4PP149 - PP160
2PP161 - PP169
2PP181 - PP199
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GroupVariable Number
2PP201 - PP205
2PP221
2PP231 - PP243
2PP281 - PP286
2PP301 - PP305
2PP351 - PP353
2PP376 - PP384
2PP391 - PP393
2PP401 - PP440
2PP471 - PP475
2PP501 - PP510
4PP511 - PP517
7PP518 - PP520
2PP521 - PP522
2PP631 - PP634
2PP651 - PP652
2PP671 - PP699
2PP701 - PP733
2PP771 - PP779
2PP801 - PP808
2PP821 - PP827
2PP831 - PP848
2PP851 - PP852
2PP861 - PP873
4PP874 - PP875
7PP876 - PP877
2PP891 - PP899
2PP901 - PP924
4PP925 - PP930
2PP931 - PP936
2PP946 - PP948
2PP951 - PP952
2PP961 - PP967
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GroupVariable Number
2PP981 - PP987
4PP988 - PP990
2PP991
2PP993
2PQ001 - PQ016
2PQ026 - PQ041
2PQ051 - PQ073
4PQ074 - PQ085
2PQ086 - PQ092
2PQ101 - PQ198
4PQ199
4PQ201 - PQ202
2PQ221 - PQ229
4PQ230
2PQ231 - PQ236
4PQ237
2PQ241 - PQ243
2PQ251 - PQ255
4PQ256 - PQ267
2PQ281 - PQ286
4PQ287 - PQ296
7PQ297 - PQ299
2PQ301 - PQ305
4PQ306 - PQ307
2PQ331 - PQ332
4PQ341 - PQ344
7PQ345 - PQ348
4PQ361 - PQ369
7PQ370 - PQ373
7PQ391 - PQ395
4PQ401 - PQ408
7PQ409 - PQ410
4PQ411 - PQ413
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GroupVariable Number
7PQ414 - PQ418
4PQ421
7PQ431 - PQ438
7PQ447 - PQ448
7PQ451
7PQ454
4PQ471 - PQ473
7PQ474 - PQ475
4PQ479 - PQ481
4PQ486 - PQ487
4PQ491 - PQ493
4PQ771
7PQ772
4PQ791 - PQ793
4PQ801 - PQ805
4PQ931 - PQ932
7PQ933 - PQ935
7PQ951
7PQ971 - PQ997
7PR001 - PR017
7PR021 - PR034
7PR041 - PR045
7PR061 - PR072
7PR077 - PR082
7PR091 - PR092
7PR096
7PR101
7PR121 - PR122
7PR131 - PR132
7PR141 - PR143
7PR161 - PR172
7PR181
4PS601 - PS616
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GroupVariable Number
7PS617 - PS630
4PS631
4PS636 - PS638
2PS641 - PS642
4PS643 - PS644
4PS651 - PS657
2PS666 - PS668
4PS669
4PS691 - PS692
4PS701 - PS703
7PS704 - PS706
4PS751 - PS762
7PS763 - PS799
7PS811
7PS836 - PS837
7PS841 - PS846
7PS851 - PS852
7PS856
7PS861 - PS863
7PS866 - PS868
7PS871 - PS874
7PS896 - PS897
7PS901 - PS941
7PS956 - PS957
7PS961 - PS963
7PS971 - PS978
5PT001 - PT011
7PT012 - PT015
3PT021 - PT023
5PT024 - PT028
7PT029 - PT031
5PT041 - PT064
3PT101
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GroupVariable Number
5PT102 - PT105
3PT121 - PT123
5PT124 - PT125
7PT126 - PT138
3PT146
5PT147 - PT148
5PT161 - PT170
3PT181 - PT182
5PT183 - PT187
7PT188
3PT211 - PT214
5PT215 - PT220
3PT295
5PT301 - PT306
7PT307 - PT309
5PT331 - PT360
5PT381 - PT399
5PT401 - PT438
5PT501 - PT512
7PT513 - PT517
5PT561 - PT565
5PT581 - PT584
7PT585 - PT586
5PT611 - PT621
5PT641 - PT642
7PT643 - PT644
5PT651 - PT655
7PT656
5PT671 - PT672
7PT681 - PT685
5PT701 - PT703
7PT716 - PT717
7PT721 - PT725
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GroupVariable Number
7PT801 - PT834
7PT851 - PT854
7PT871 - PT886
7PT901 - PT930
7PT971 - PT973
7PT981 - PT985
7PT996
3PU001 - PU007
5PU008 - PU025
7PU301
7PU311 - PU313
2PV001 - PV040
4PV041 - PV055
4PV201 - PV203
7PV204 - PV209
7PV226 - PV229
4PV231 - PV237
4PV271 - PV272
4PV281 - PV283
7PV284 - PV287
7PV296
7PV301 - PV302
7PV351
7PV356 - PV357
2PW001 - PW036
4PW037 - PW050
2PW051
4PW052 - PW054
2PW061 - PW063
4PW064 - PW068
4PW072
7PW086 - PW088
2PW091 - PW093
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GroupVariable Number
4PW094
4PW101 - PW102
4PW106
2PW111 - PW117
4PW118 - PW120
4PW156 - PW157
2PW161 - PW162
4PW163 - PW167
7PW168 - PW171
4PW201 - PW245
7PW246 - PW252
4PW261
7PW262 - PW264
4PW265 - PW268
7PW271 - PW276
4PW278
4PW281 - PW284
7PW285 - PW292
4PW293
4PW296
4PW301 - PW327
7PW401 - PW408
7PW411 - PW418
7PW421 - PW424
7PW431 - PW435
7PW441 - PW450
4PW461 - PW467
2PW501 - PW503
4PW504
2PW511 - PW518
4PW519 - PW520
7PW521 - PW522
7PW524 - PW525
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GroupVariable Number
4PW526
7PW527 - PW530
2PW531 - PW535
4PW536 - PW546
7PW547 - PW550
4PW556 - PW557
2PW561 - PW563
4PW564
2PW571 - PW573
4PW574 - PW576
2PW591 - PW594
4PW595 - PW596
2PW611 - PW615
4PW616 - PW620
7PW621 - PW622
2PW631 - PW632
4PW633 - PW634
7PW635 - PW637
2PW661
4PW662
4PW681 - PW683
4PW701 - PW702
4PW711 - PW717
4PW741 - PW742
4PW761
4PW771
7PW831
7PW851 - PW856
1PX071
1PX701
1PY001 - PY008
1PY021
6PY022
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GroupVariable Number
1PY031
6PY036 - PY037
6PY046 - PY048
6PY051 - PY053
6PY056 - PY057
6PY101 - PY103
6PY111 - PY113
6PY131 - PY135
6PY141 - PY143
6PY151 - PY154
6PY156 - PY157
6PY161 - PY162
6PY166
6PY191
6PY201
6PY221 - PY222
6PY231
6PY241 - PY244
6PY270 - PY275
6PY281
6PY286
1PY301 - PY304
1PY321 - PY323
1PY341 - PY346
1PY361 - PY362
1PY381
6PY401
6PY409 - PY411
6PY421 - PY422
6PY441
6PY451
6PY461 - PY463
6PY591 - PY595
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GroupVariable Number
6PY611 - PY612
6PY621
6PY631
6PY651
6PY671 - PY672
6PY721
6PY741
2. Spares Affected
None.
B. Concurrent Requirements
None.
C. Reason
This service bulletin is sent to inspect frames at STA 328 between stringers S-20R to S-21R, STA 360
between stringers S-19R to S-21R, and STA 380 between stringers S-18R to S-22R for cracking.
Operators have sent in reports of cracking in these frames. Also, this service bulletin inspects adjacent
frames at STA 312 between stringers S-19R to S-22R and STA 344 between stringers S-18R to S-22R.
In addition, this service bulletin inspects the frame at STA 312 for a missing strap adjacent to stringer
S-22R. A missing strap can make the frame crack. If cracks in the frames are not detected and repaired,
they can grow until the frames sever. Continued operation of the airplane with multiple adjacent severed
frames can result in uncontrolled decompression of the airplane, and also, the combination of a severed
frame and fuselage skin chem mill cracks in this area can result in uncontrolled decompression of the
airplane.
Refer to Boeing Service Bulletin 737-53A1210 for reports of fuselage skin chem mill cracks.
Accomplishment of the inspections in this service bulletin will make sure that cracks in the frames at
STA 328 between stringers S-20R to S-21R, STA 360 between stringers S-19R to S-21R, and STA
380 between stringer S-18R to S-22R are found and repaired. Also, accomplishment of the inspections
in this service bulletin will make sure that cracks in adjacent frames at STA 312 between stringers
S-19R to S-22R and STA 344 between stringers S-19R to S-22R are found and repaired. If cracks in
the frames are found and repaired, then the effect of a severed frame can not interact with the effect
of fuselage skin cracks. In addition, accomplishment of the inspection in this service bulletin will ensure
that the strap adjacent to stringer S-22R on the frame at STA 312 is installed.
One operator of a 737-300 airplane sent a report of a crack in the frame at STA 328 and a crack that
severed the frame at STA 360 on the right side of the same airplane with 59,756 flight cycles. The
crack in the frame at STA 328 was between stringers S-20R to S-21R. The crack length was not
reported. The crack in the frame at STA 360 was between stringers S-19R to S-20R. The frame web
and the failsafe chord were completely severed.
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Operators of 737-200, 737-300, and 737-500 airplanes sent ten reports of cracks in the frame at STA
328 between stringers S-20R and S-21R on ten airplanes with 43,581 to 73,655 flight cycles. Cracks
were in the frame web at an open tool hole, in the frame web at the end fastener in the inner chord,
and in the frame web notch. The cracks were from 0.3 inch to 3.0 inches long.
Operators of 737-200 and 737-300 airplanes sent fourteen reports of cracks in the frame at STA 360
between stringers S-19R and S-21R on fourteen airplanes with 42,183 to 66,588 flight cycles. Cracks
were in the frame web at an open tool hole, in the frame web at an insulation blanket stud hole, in the
frame web at an end fastener in the doubler, and in the inner flange at the end fastener in the doubler.
The cracks were from 2.5 inches long to cracks that severed the frame web and fail-safe chord.
An operator of a 737-300 airplane sent one report of three cracks in the frame at STA 380 between
stringers S-18R and S-20R on one airplane with 32,218 flight cycles. Cracks were in the frame inner
flange at fasteners common to the bulkhead support angle. One of the three cracks was also in the
doubler. Crack lengths were not reported.
An operator of a 737-400 airplane sent in one report of a strap that was not installed on the frame at
STA 312 adjacent to stringer S-22R on one airplane with 24,037 flight cycles. Investigation of the
drawings revealed that this was an incorrect frame configuration and that the strap should have been
installed. The incorrect frame configuration was discovered during a repair of the STA 312 frame
because of ground damage. There was no report of cracks caused by the incorrect frame configuration.
Boeing Fleet Team Digest (FTD) 737 FTD 53-10001 is related to this service bulletin.
Boeing Service Related Problem (SRP) 737-SRP-53-0359 is related to this service bulletin.
D. Description
Group 1:
On Group 1 airplanes, contact Boeing to get instructions for the inspection and/or repair for this service
bulletin, and do the work instructed by Boeing.
Group 2-5:
On the frame at STA 312, do a general visual inspection of the frame to make sure that the strap
adjacent to stringer S-22R is installed. If the strap is installed, then no more work is necessary to make
sure that the strap is installed. If the strap is not installed, then before further flight, repair the frame at
STA 312.
On the frame at STA 328, do a detailed inspection between stringers S-20R to S-21R for cracking or
a severed frame web. Do an open hole High Frequency Eddy Current (HFEC) inspection of a tool hole
in the frame web for cracking, a surface HFEC inspection of the frame web around the end fastener in
the inner chord for cracking, and a surface HFEC inspection of the frame web notch for cracking. If no
crack is found, then continue to do repeat inspections. If any crack is found, then before further flight,
repair the frame. If a severed frame web is found, then before further flight, repair the frame, do a
detailed inspection of the frame at STA 312 between stringers S-19R to S-22R for cracking, do a
detailed inspection of the frame at STA 344 between stringers S-18R to S-22R for cracking, and do
detailed and eddy current inspections of the fuselage skin for cracking. If no crack is found, then no
more work is necessary on the frame at STA 312, but continue to do repeat inspections of the frame
at STA 344. If any crack is found on the frame at STA 312, or on the frame at STA 344, then before
further flight, repair the frame. If any crack is found in the fuselage skin, then before further flight, repair
the skin. If you do the repair of the frame at STA 328 in accordance with this service bulletin, then you
can stop repeat inspections of the frame at STA 328. Do post-repair damage tolerance inspections of
the repair of the frame at STA 328.
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### Page 30

On the frame at STA 344, do a detailed inspection between stringers S-18R to S-22R for cracking. If
no crack is found, then continue to do repeat inspections. If any crack is found, then before further
flight, repair the frame at STA 344. If you do the repair of the frame at STA 328 in accordance with this
service bulletin, and you do the optional preventative modification to the frame at STA 360 in accordance
with this service bulletin, then you can stop repeat inspections of the frame at STA 344.
On the frame at STA 360, do a detailed inspection between stringers S-19R to S-21R for cracking or
a severed frame web. Do an open hole HFEC inspection of a tool hole in the frame web for cracking,
an open hole HFEC inspection of an insulation blanket stud hole in the frame web for cracking, a surface
HFEC inspection of the frame web around an end fastener in the doubler, and a surface HFEC inspection
of the inner flange around the end fastener in the doubler for cracking. If no crack is found, then continue
to do repeat inspections. If any crack is found, then before further flight, repair the frame at STA 360.
If a severed frame web is found, then before further flight, repair the frame at STA 360, do a detailed
inspection of the frame at STA 344 between stringers S-18R to S-22R for cracking, do a detailed
inspection of the frame at STA 380 between stringers S-18R to S-22R for cracking, and do detailed
and eddy current inspections of the fuselage skin for cracking. If no crack is found, then continue to do
repeat inspections on the frame at STA 344, and the frame at STA 380. If any crack is found in the
frame at STA 344, or on the frame at STA 380, then before further flight, repair the frame. If any crack
is found in the fuselage skin, then before further flight, repair the skin. If you do the optional preventative
modification to the frame at STA 360 in accordance with this service bulletin, then you can stop repeat
inspections of the frame at STA 360. Do post-modification damage tolerance inspections of the modified
area of the frame at STA 360.
On the frame at STA 380, do a detailed inspection of the frame between stringers S-18R to S-22R for
cracking or a severed frame web. Do a surface HFEC inspection of the inner flange adjacent to fasteners
common to the bulkhead support angle in the frame at STA 380 for cracking. If no crack is found, then
continue to do repeat inspections. If any crack is found, then before further flight, repair the frame at
STA 380. If a severed frame web is found, then before further flight, repair the frame at STA 380 and
inspect adjacent structure.
On the fuselage skin adjacent to the frames at STA 328 and STA 360 inspected by this service bulletin,
you can do optional external detailed and eddy current inspections for cracking. If you do the optional
inspections of the fuselage skin, you can increase the repeat inspection intervals for the frames. If no
crack is found in the fuselage skin, then you must continue to do repeat inspections of the fuselage
skin for cracking. If any crack is found, then before further flight, repair the fuselage skin, do a detailed
inspection of the frame at STA 328 between stringers S-20R to S-21R for cracking, and do a detailed
inspection of the frame at STA 360 between stringers S-19R to S-21R for cracking. If any crack is found
on the frame at STA 328, or on the frame at STA 360, then before further flight, repair the frame. You
must continue to do repeat inspections of the unrepaired area of the fuselage skin for cracking. If you
do a repair of the fuselage skin in accordance with this service bulletin, then you can stop repeat
inspections of the skin common to the repair. Do post-repair damage tolerance inspections of the repair
of the fuselage skin. If you do the repair of the frame at STA 328 in accordance with this service bulletin,
and you do the optional preventative modification to the frame at STA 360 in accordance with this
service bulletin, then you can stop repeat inspections of the fuselage skin in accordance with this
service bulletin. Refer to AMOC in Paragraph 1.F., Approval.
Group 6:
On the frame at STA 312, do a general visual inspection of the frame to make sure that the strap
adjacent to stringer S-22R is installed. If the strap is installed, then no more work is necessary to make
sure that the strap is installed. If the strap is not installed, then before further flight, repair the frame at
STA 312.
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### Page 31

On the frame at STA 328, do a detailed inspection between stringers S-20R to S-21R for cracking or
a severed frame web. Do an open hole High Frequency Eddy Current (HFEC) inspection of a tool hole
in the frame web for cracking, a surface HFEC inspection of the frame web around the end fastener in
the inner chord for cracking, and a surface HFEC inspection of the frame web notch for cracking. If no
crack is found, then continue to do repeat inspections. If any crack is found, then before further flight,
repair the frame. If a severed frame web is found, then before further flight, repair the frame, do a
detailed inspection of the frame at STA 312 between stringers S-19R to S-22R for cracking, do a
detailed inspection of the frame at STA 344 between stringers S-18R to S-22R for cracking, and do
detailed and eddy current inspections of the fuselage skin for cracking. If no crack is found, then no
more work is necessary on the frame at STA 312, or on the frame at STA 344. If any crack is found on
the frame at STA 312, or on the frame at STA 344, then before further flight, repair the frame. If any
crack is found in the fuselage skin, then before further flight, repair the skin. If you do the repair of the
frame at STA 328 in accordance with this service bulletin, then you can stop repeat inspections of the
frame at STA 328. Do post-repair damage tolerance inspections of the repair of the frame at STA 328.
On the fuselage skin adjacent to the frame at STA 328 inspected by this service bulletin, you can do
optional external detailed and eddy current inspections for cracking. If you do the optional inspections
of the fuselage skin, then you can increase the repeat inspection interval for the frame. If no crack is
found in the fuselage skin, then you must continue to do repeat inspections of the fuselage skin. If any
crack is found, then before further flight, repair the fuselage skin and do a detailed inspection of the
frame at STA 328 between stringers S-20R to S-21R for cracking. If any crack is found on the frame
at STA 328, then before further flight, repair the frame. You must continue to do repeat inspections of
the unrepaired area of the fuselage skin for cracking. If you do skin repairs in accordance with this
service bulletin, then you can stop repeat inspections of the skin common to the repair. Do post-repair
damage tolerance inspections of the repair of the fuselage skin. If you do the repair of the frame at
STA 328 in accordance with this service bulletin, then you can stop repeat inspections of the fuselage
skin in accordance with this service bulletin. Refer to AMOC in Paragraph 1.F., Approval.
Group 7:
On the frame at STA 312, do a general visual inspection of the frame to make sure that the strap
adjacent to stringer S-22R is installed. If the strap is installed, then no more work is necessary to make
sure that the strap is installed. If the strap is not installed, then before further flight, repair the frame at
STA 312.
On the frame at STA 328, do a detailed inspection between stringers S-20R to S-21R for cracking or
a severed frame web. Do an open hole High Frequency Eddy Current (HFEC) inspection of an tool
hole in the frame web for cracking, a surface HFEC inspection of the frame web around the end fastener
in the inner chord for cracking, and a surface HFEC inspection of the frame web notch for cracking. If
no crack is found, then continue to do repeat inspections. If any crack is found, then before further
flight, repair the frame. If a severed frame web is found, then before further flight, repair the frame, do
a detailed inspection of the frame at STA 312 between stringers S-19R to S-22R for cracking, and do
a detailed inspection of the frame at STA 344 between stringers S-18R to S-22R for cracking. If no
crack is found, then no more work is necessary on the frame at STA 312, or on the frame at STA 344.
If any crack is found on the frame at STA 312, or on the frame at STA 344, then before further flight,
repair the frame. If you do the repair of the frame at STA 328 in accordance with this service bulletin,
then you can stop repeat inspections of the frame at STA 328. Do post-repair damage tolerance
inspections of the repair of the frame at STA 328.
The work in this service bulletin is done in the maintenance zone(s) given below.
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### Page 32

Group 1:
Affected Maintenance Zones
ZoneModel
2-5, 2-8737-100, 737-200, 737-200C
Group 2:
Affected Maintenance Zones
ZoneModel
2-5, 2-8737-200
Group 2, 4:
Affected Maintenance Zones
ZoneModel
205, 208737-300, 737-400
Group 3, 5:
Affected Maintenance Zones
ZoneModel
205, 208737-500
Group 6:
Affected Maintenance Zones
ZoneModel
2-5737-200C
Group 7:
Affected Maintenance Zones
ZoneModel
205737-300, 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.
Do the required actions in accordance with Paragraph 3. Accomplishment Instructions.
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### Page 33

Group 1:
Table 1: Inspection and/or Repair for Group 1 Airplanes.
Repeat Interval
(Not to Exceed)
Compliance Time (Whichever
Occurs Later)
ActionCondition
-Within 1,250
flight cycles af-
ter the original
issue date of
this service bul-
letin.
Before 20,000
total flight cy-
cles.
Contact Boeing to get in-
structions for the inspec-
tion and/or repair for this
service bulletin, and do
the work instructed by
Boeing.
All Airplanes.
Group 2-6:
Table 2: Inspection of the Frame at STA 312 to Make Sure Strap is Installed
Repeat Inter-
val (Not to
Exceed)
Compliance Time (Whichever
Occurs Later )
ActionCondition
-Within 2,200
flight cycles af-
ter the original
issue date of
this Service
Bulletin.
Before 20,000
total flight cy-
cles.
Do a general visual inspection of
the frame at STA 312 to make
sure that the strap adjacent to
stringer S-22R is installed in accor-
dance with Accomplishment In-
structions 3.B.3.
All airplanes.
-Before further flightContact Boeing to get instructions
for the repair for this service bul-
letin, and do the work instructed
by Boeing.
The strap adjacent to
stringer S-22R is not in-
stalled.
Group 7:
Table 3: Inspection of the Frame at STA 312 to Make Sure Strap is Installed
Repeat Inter-
val (Not to
Exceed)
Compliance Time (Whichever
Occurs Later )
ActionCondition
-Within 4,500
flight cycles af-
ter the original
issue date of
this Service
Bulletin.
Before 30,000
total flight cy-
cles.
Do a general visual inspection of
the frame at STA 312 to make
sure that the strap adjacent to
stringer S-22R is installed in accor-
dance with Accomplishment In-
structions 3.B.3.
All airplanes.
-Before further flightContact Boeing to get instructions
for the repair for this service bul-
letin, and do the work instructed
by Boeing.
The strap adjacent to
stringer S-22R is not in-
stalled.
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### Page 34

Group 2-5:
Table 4: Inspections of the Frame at STA 328 for Cracking and Optional Inspections of the Adjacent
Fuselage Skin for Cracking
Repeat Inter-
val (Not to
Exceed)
Compliance Time (Whichever
Occurs Later )
ActionCondition
4,500 flight
cycles until
Option 1 or
Option 2 is
started. (a)
Within 2,200
flight cycles af-
ter the original
issue date of
this Service
Bulletin.
Before 20,000
total airplane
flight cycles.
Do detailed and eddy current in-
spections of the frame at STA 328
for cracking or a severed frame
web in accordance with Accom-
plishment Instructions 3.B.3.
Airplanes that have less
than 28,300 total flight cy-
cles at the original issue
date of this Service Bulletin.
--And do one of the options that
follow:
OPTION 1: (b)
2,200 flight
cycles (a)
-Before 35,000
total flight cy-
cles but not to
exceed 4,500
flight cycles
from the last in-
spection.
Do detailed and eddy current in-
spections of the frame at STA 328
for cracking or a severed frame
web in accordance with Accom-
plishment Instructions 3.B.3.
OPTION 2: (b) (c)
4,500 flight
cycles (a)
-Before 35,000
total flight cy-
cles but not to
exceed 4,500
flight cycles
from the last in-
spection.
Do detailed and eddy current in-
spections of the frame at STA 328
for cracking or a severed frame
web in accordance with Accom-
plishment Instructions 3.B.3.
1,250 flight
cycles. (d)
(e)
-Before 35,000
total flight cy-
cles but not to
exceed 4,500
flight cycles
from the last in-
spection. (d)
Do external detailed and eddy
current inspections of the fuselage
skin for cracking in accordance
with Accomplishment Instructions
3.B.4.
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### Page 35

Group 2-5:
Table 4: Inspections of the Frame at STA 328 for Cracking and Optional Inspections of the Adjacent
Fuselage Skin for Cracking
Repeat Inter-
val (Not to
Exceed)
Compliance Time (Whichever
Occurs Later )
ActionCondition
--Do one of the options that follow:Airplanes that have 28,300
total flight cycles or more
but less than 32,800 total
flight cycles at the original
issue date of this Service
Bulletin.
OPTION 1: (b)
2,200 flight
cycles (a)
Within 2,200
flight cycles af-
ter the original
issue date of
this Service
Bulletin.
-Do detailed and eddy current in-
spections of the frame at STA 328
for cracking or a severed frame
web in accordance with Accom-
plishment Instructions 3.B.3.
OPTION 2: (b) (c)
4,500 flight
cycles (a)
Within 4,500
flight cycles af-
ter the original
issue date of
this Service
Bulletin.
-Do detailed and eddy current in-
spections of the frame at STA 328
for cracking or a severed frame
web in accordance with Accom-
plishment Instructions 3.B.3.
1,250 flight
cycles. (d)
(e)
Within 2,200
flight cycles af-
ter the original
issue date of
this Service
Bulletin. (d)
-Do external detailed and eddy
current inspections of the fuselage
skin for cracking in accordance
with Accomplishment Instructions
3.B.4.
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### Page 36

Group 2-5:
Table 4: Inspections of the Frame at STA 328 for Cracking and Optional Inspections of the Adjacent
Fuselage Skin for Cracking
Repeat Inter-
val (Not to
Exceed)
Compliance Time (Whichever
Occurs Later )
ActionCondition
--Do one of the options that follow:Airplanes that have 32,800
total flight cycles or more at
the original issue date of
this Service Bulletin.
OPTION 1: (b)
2,200 flight
cycles (a)
Within 1,250
flight cycles af-
ter the original
issue date of
this Service
Bulletin.
Before 35,000
total flight cy-
cles.
Do detailed and eddy current in-
spections of the frame at STA 328
for cracking or a severed frame
web in accordance with Accom-
plishment Instructions 3.B.3.
OPTION 2: (b) (c)
4,500 flight
cycles (a)
Within 1,250
flight cycles af-
ter the original
issue date of
this Service
Bulletin.
Before 35,000
total flight cy-
cles.
Do detailed and eddy current in-
spections of the frame at STA 328
for cracking or a severed frame
web in accordance with Accom-
plishment Instructions 3.B.3.
1,250 flight
cycles. (d)
(e)
Within 1,250
flight cycles af-
ter the original
issue date of
this Service
Bulletin. (d)
Before 35,000
total flight cy-
cles. (d)
Do external detailed and eddy
current inspections of the fuselage
skin for cracking in accordance
with Accomplishment Instructions
3.B.4.
-Before further flight.Do the repair of the frame at STA
328 in accordance with Accom-
plishment Instruction 3.B.6.
Any crack is found in the
frame web at the tool hole,
in the frame web at the end
fastener in the inner chord,
or in the frame web at the
frame web notch during in-
spections of the frame at
STA 328.
-Before further flight.Contact Boeing to get instructions
for the repair for this service bul-
letin, and do the work instructed
by Boeing.
Any other crack is found
during inspections of the
frame at STA 328.
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### Page 37

Group 2-5:
Table 4: Inspections of the Frame at STA 328 for Cracking and Optional Inspections of the Adjacent
Fuselage Skin for Cracking
Repeat Inter-
val (Not to
Exceed)
Compliance Time (Whichever
Occurs Later )
ActionCondition
-Before further flight.Contact Boeing to get instructions
for the repair for this service bul-
letin, and do the work instructed
by Boeing.
A severed frame web is
found during inspections of
the frame at STA 328 and
you did not do inspections
of the fuselage skin at the
time that you found the
severed frame web.
-
Do a detailed inspection of the
adjacent frame at STA 312 for
cracking in accordance with Ac-
complishment Instruction 3.B.3.
-
Do a detailed inspection of the
adjacent frame at STA 344 for
cracking in accordance with Ac-
complishment Instruction 3.B.3
-
Do external detailed and eddy
current inspections of the fuselage
skin for cracking in accordance
with Accomplishment Instruction
3.B.4.
-Before further flight.Contact Boeing to get instructions
for the repair for this service bul-
letin, and do the work instructed
by Boeing.
A severed frame web is
found during inspections of
the frame at STA 328 and
you did do inspections of
the fuselage skin at the time
that you found the severed
frame web.
-
Do a detailed inspection of the
adjacent frame at STA 312 for
cracking in accordance with Ac-
complishment Instruction 3.B.3.
-
Do a detailed inspection of the
adjacent frame at STA 344 for
cracking in accordance with Ac-
complishment Instruction 3.B.3
-Before further flightContact Boeing to get instructions
for the repair for this service bul-
letin, and do the work instructed
by Boeing.
Any crack is found during
inspection of the frame at
STA 312.
-Before further flightContact Boeing to get instructions
for the repair for this service bul-
letin, and do the work instructed
by Boeing.
Any crack is found during
inspection of the frame at
STA 344.
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### Page 38

Group 2-5:
Table 4: Inspections of the Frame at STA 328 for Cracking and Optional Inspections of the Adjacent
Fuselage Skin for Cracking
Repeat Inter-
val (Not to
Exceed)
Compliance Time (Whichever
Occurs Later )
ActionCondition
-Before further flight.Repair the fuselage skin in accor-
dance with Accomplishment In-
structions 3.B.7.
Any crack is found during
inspections of the fuselage
skin and you did not do in-
spections of the frame at
STA 328 and the frame at
STA 360 at the time that
you found the crack in the
fuselage skin.
-
Do detailed and eddy current in-
spections of the frame at STA 328
for cracking or a severed frame
web in accordance with Accom-
plishment Instruction 3.B.3. Do the
actions in accordance with Para-
graph 1.E., Compliance, Table 4
for the conditions found.
-
Do detailed and eddy current in-
spections of the frame at STA 360
for cracking or a severed frame
web in accordance with Accom-
plishment Instruction 3.B.3. Do the
actions in accordance with Para-
graph 1.E., Compliance, Table 8
for the conditions found.
-Before further flight.Repair the fuselage skin in accor-
dance with Accomplishment In-
structions 3.B.7.
Any crack is found during
inspections of the fuselage
skin and you did do inspec-
tions of the frame at STA
328 and the frame at STA
360 at the time that you
found the crack in the fuse-
lage skin.
(a) If you do the repair of the frame at STA 328 in accordance with Accomplishment Instructions 3.B.6., then
you can stop repeat inspections of the frame. You can do the repair of the frame at STA 328 as an optional
preventative modification in accordance with Accomplishment Instruction 3.B.6.
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### Page 39

Group 2-5:
Table 4: Inspections of the Frame at STA 328 for Cracking and Optional Inspections of the Adjacent
Fuselage Skin for Cracking
Repeat Inter-
val (Not to
Exceed)
Compliance Time (Whichever
Occurs Later )
ActionCondition
(b) It is acceptable to change inspection procedures from Option 1 to Option 2 or from Option 2 to Option 1
if you do as follows:
1 - If the inspection procedure is being changed from Option 1 to Option 2, then the first Option 2 inspections
(external skin and internal frame) must be done within 2,200 flight cycles after the most recent Option 1
inspection. The Option 2 repeat inspections that follow must be done at the Option 2 repeat intervals in
accordance with Paragraph 1.E., Compliance, Table 4.
2 - If the inspection procedure is being changed from Option 2 to Option 1, then the first Option 1 inspection
must be done within 1,250 flight cycles after the most recent Option 2 inspection (external skin or internal
frame). The Option 1 repeat inspections that follow must be done at the Option 1 repeat intervals in accor-
dance with Paragraph 1.E., Compliance, Table 4.
(c) It is recommended that actions in Option 2 on the frames at STA 328 and STA 344 are done concurrently.
(d) It is not necessary to inspect the area under an external fuselage skin repair that is installed in accordance
with Accomplishment Instruction 3.B.4. If the repair is not installed in accordance with Accomplishment
Instruction 3.B.4, then do an internal inspection of the area under the external fuselage skin repair in ac-
cordance with Accomplishment Instruction 3.B.4.
(e) If you do both of the actions that follow, then you can stop repeat inspections of the fuselage skin in accor-
dance with this service bulletin:
1 - Do the optional preventative modification of the frame at STA 360 in accordance with Accomplishment
Instructions 3.B.5.
2 - Do the repair of the frame at STA 328 in accordance with Accomplishment Instructions 3.B.6.
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### Page 40

Group 6:
Table 5: Inspections of the Frame at STA 328 for Cracking and Optional Inspections of the Adjacent
Fuselage Skin for Cracking
Repeat Inter-
val (Not to
Exceed)
Compliance Time (Whichever
Occurs Later )
ActionCondition
4,500 flight
cycles until
Option 1 or
Option 2 is
started. (a)
Within 2,200
flight cycles af-
ter the original
issue date of
this Service
Bulletin.
Before 20,000
total airplane
flight cycles.
Do detailed and eddy current in-
spections of the frame at STA 328
for cracking or a severed frame
web in accordance with Accom-
plishment Instructions 3.B.3.
Airplanes that have less
than 28,300 total flight cy-
cles at the original issue
date of this Service Bulletin.
--And do one of the options that
follow:
OPTION 1: (b)
2,200 flight
cycles (a)
-Before 35,000
total flight cy-
cles but not to
exceed 4,500
flight cycles
from the last in-
spection.
Do detailed and eddy current in-
spections of the frame at STA 328
for cracking or a severed frame
web in accordance with Accom-
plishment Instructions 3.B.3.
OPTION 2: (b)
4,500 flight
cycles (a)
-Before 35,000
total flight cy-
cles but not to
exceed 4,500
flight cycles
from the last in-
spection.
Do detailed and eddy current in-
spections of the frame at STA 328
for cracking or a severed frame
web in accordance with Accom-
plishment Instructions 3.B.3.
1,250 flight
cycles. (c)
(d)
-Before 35,000
total flight cy-
cles but not to
exceed 4,500
flight cycles
from the last in-
spection. (c)
Do external detailed and eddy
current inspections of the fuselage
skin for cracking in accordance
with Accomplishment Instructions
3.B.4.
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### Page 41

Group 6:
Table 5: Inspections of the Frame at STA 328 for Cracking and Optional Inspections of the Adjacent
Fuselage Skin for Cracking
Repeat Inter-
val (Not to
Exceed)
Compliance Time (Whichever
Occurs Later )
ActionCondition
--Do one of the options that follow:Airplanes that have 28,300
total flight cycles or more
but less than 32,800 total
flight cycles at the original
issue date of this Service
Bulletin.
OPTION 1: (b)
2,200 flight
cycles (a)
Within 2,200
flight cycles af-
ter the original
issue date of
this Service
Bulletin.
-Do detailed and eddy current in-
spections of the frame at STA 328
for cracking or a severed frame
web in accordance with Accom-
plishment Instructions 3.B.3.
OPTION 2: (b)
4,500 flight
cycles (a)
Within 4,500
flight cycles af-
ter the original
issue date of
this Service
Bulletin.
-Do detailed and eddy current in-
spections of the frame at STA 328
for cracking or a severed frame
web in accordance with Accom-
plishment Instructions 3.B.3.
1,250 flight
cycles. (c)
(d)
Within 2,200
flight cycles af-
ter the original
issue date of
this Service
Bulletin. (c)
-Do external detailed and eddy
current inspections of the fuselage
skin for cracking in accordance
with Accomplishment Instructions
3.B.4.
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### Page 42

Group 6:
Table 5: Inspections of the Frame at STA 328 for Cracking and Optional Inspections of the Adjacent
Fuselage Skin for Cracking
Repeat Inter-
val (Not to
Exceed)
Compliance Time (Whichever
Occurs Later )
ActionCondition
--Do one of the options that follow:Airplanes that have 32,800
total flight cycles or more at
the original issue date of
this Service Bulletin.
OPTION 1: (b)
2,200 flight
cycles (a)
Within 1,250
flight cycles af-
ter the original
issue date of
this Service
Bulletin.
Before 35,000
total flight cy-
cles.
Do detailed and eddy current in-
spections of the frame at STA 328
for cracking or a severed frame
web in accordance with Accom-
plishment Instructions 3.B.3.
OPTION 2: (b)
4,500 flight
cycles (a)
Within 1,250
flight cycles af-
ter the original
issue date of
this Service
Bulletin.
Before 35,000
total flight cy-
cles.
Do detailed and eddy current in-
spections of the frame at STA 328
for cracking or a severed frame
web in accordance with Accom-
plishment Instructions 3.B.3.
1,250 flight
cycles. (c)
(d)
Within 1,250
flight cycles af-
ter the original
issue date of
this Service
Bulletin. (c)
Before 35,000
total flight cy-
cles. (c)
Do external detailed and eddy
current inspections of the fuselage
skin for cracking in accordance
with Accomplishment Instructions
3.B.4.
-Before further flight.Do the repair of the frame at STA
328 in accordance with Accom-
plishment Instruction 3.B.6.
Any crack is found in the
frame web at the tool hole,
in the frame web at the end
fastener in the inner chord,
or in the frame web at the
frame web notch during in-
spections of the frame at
STA 328.
-Before further flight.Contact Boeing to get instructions
for the repair for this service bul-
letin, and do the work instructed
by Boeing.
Any other crack is found
during inspections of the
frame at STA 328.
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### Page 43

Group 6:
Table 5: Inspections of the Frame at STA 328 for Cracking and Optional Inspections of the Adjacent
Fuselage Skin for Cracking
Repeat Inter-
val (Not to
Exceed)
Compliance Time (Whichever
Occurs Later )
ActionCondition
-Before further flight.Contact Boeing to get instructions
for the repair for this service bul-
letin, and do the work instructed
by Boeing.
A severed frame web is
found during inspections of
the frame at STA 328 and
you did not do inspections
of the fuselage skin at the
time that you found the
severed frame web.
-
Do a detailed inspection of the
adjacent frame at STA 312 for
cracking in accordance with Ac-
complishment Instruction 3.B.3.
-
Do a detailed inspection of the
adjacent frame at STA 344 for
cracking in accordance with Ac-
complishment Instruction 3.B.3
-
Do external detailed and eddy
current inspections of the fuselage
skin for cracking in accordance
with Accomplishment Instruction
3.B.4.
-Before further flight.Contact Boeing to get instructions
for the repair for this service bul-
letin, and do the work instructed
by Boeing.
A severed frame web is
found during inspections of
the frame at STA 328 and
you did do inspections of
the fuselage skin at the time
that you found the severed
frame web.
-
Do a detailed inspection of the
adjacent frame at STA 312 for
cracking in accordance with Ac-
complishment Instruction 3.B.3.
-
Do a detailed inspection of the
adjacent frame at STA 344 for
cracking in accordance with Ac-
complishment Instruction 3.B.3
-Before further flightContact Boeing to get instructions
for the repair for this service bul-
letin, and do the work instructed
by Boeing.
Any crack is found during
inspection of the frame at
STA 312.
-Before further flightContact Boeing to get instructions
for the repair for this service bul-
letin, and do the work instructed
by Boeing.
Any crack is found during
inspection of the frame at
STA 344.
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### Page 44

Group 6:
Table 5: Inspections of the Frame at STA 328 for Cracking and Optional Inspections of the Adjacent
Fuselage Skin for Cracking
Repeat Inter-
val (Not to
Exceed)
Compliance Time (Whichever
Occurs Later )
ActionCondition
-Before further flight.Repair the fuselage skin in accor-
dance with Accomplishment In-
structions 3.B.7.
Any crack is found during
inspections of the fuselage
skin and you did not do in-
spections of the frame at
STA 328 at the time that
you found the crack in the
fuselage skin.
-
Do detailed and eddy current in-
spections of the frame at STA 328
for cracking or a severed frame
web in accordance with Accom-
plishment Instruction 3.B.3. Do the
actions in accordance with Para-
graph 1.E., Compliance, Table 5
for the conditions found.
-Before further flight.Repair the fuselage skin in accor-
dance with Accomplishment In-
structions 3.B.7.
Any crack is found during
inspections of the fuselage
skin and you did do inspec-
tions of the frame at STA
328 at the time that you
found the crack in the fuse-
lage skin.
(a) If you do the repair of the frame at STA 328 in accordance with Accomplishment Instructions 3.B.6., then
you can stop repeat inspections of the frame. You can do the repair of the frame at STA 328 as an optional
preventative modification in accordance with Accomplishment Instruction 3.B.6.
(b) It is acceptable to change inspection procedures from Option 1 to Option 2 or from Option 2 to Option 1
if you do as follows:
1 - If the inspection procedure is being changed from Option 1 to Option 2, then the first Option 2 inspections
(external skin and internal frame) must be done within 2,200 flight cycles after the most recent Option 1
inspection. The Option 2 repeat inspections that follow must be done at the Option 2 repeat intervals in
accordance with Paragraph 1.E., Compliance, Table 5.
2 - If the inspection procedure is being changed from Option 2 to Option 1, then the first Option 1 inspection
must be done within 1,250 flight cycles after the most recent Option 2 inspection (external skin or internal
frame). The Option 1 repeat inspections that follow must be done at the Option 1 repeat intervals in accor-
dance with Paragraph 1.E., Compliance, Table 5.
(c) It is not necessary to inspect the area under an external fuselage skin repair that is installed in accordance
with Accomplishment Instruction 3.B.4. If the repair is not installed in accordance with Accomplishment
Instruction 3.B.4, then do an internal inspection of the area under the external fuselage skin repair in ac-
cordance with Accomplishment Instruction 3.B.4.
(d) If you do the repair of the frame at STA 328 in accordance with Accomplishment Instructions 3.B.6., then
you can stop repeat inspections of the fuselage skin in accordance with this service bulletin.
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### Page 45

Group 7:
Table 6: Inspections of the Frame at STA 328 for Cracking
Repeat Inter-
val (Not to
Exceed)
Compliance Time (Whichever
Occurs Later )
ActionCondition
19,000 flight
cycles (a)
Within 4,500
flight cycles af-
ter the original
issue date of
this Service
Bulletin.
Before 30,000
total flight cy-
cles.
Do detailed and eddy current in-
spections of the frame at STA 328
for cracking or a severed frame
web in accordance with Accom-
plishment Instructions 3.B.3.
All airplanes.
-Before further flight.Do the repair of the frame at STA
328 in accordance with Accom-
plishment Instruction 3.B.6.
Any crack is found in the
frame web at the tool hole,
in the frame web at the end
fastener in the inner chord,
or in the frame web at the
frame web notch during in-
spections of the frame at
STA 328.
-Before further flight.Contact Boeing to get instructions
for the repair for this service bul-
letin, and do the work instructed
by Boeing.
Any other crack is found
during inspections of the
frame at STA 328.
-Before further flight.Contact Boeing to get instructions
for the repair for this service bul-
letin, and do the work instructed
by Boeing.
A severed frame web is
found in the frame web dur-
ing inspections of the frame
at STA 328.
-
Do a detailed inspection of the
adjacent frame at STA 312 for
cracking in accordance with Ac-
complishment Instruction 3.B.3.
-
Do a detailed inspection of the
adjacent frame at STA 344 for
cracking in accordance with Ac-
complishment Instruction 3.B.3.
-Before further flightContact Boeing to get instructions
for the repair for this service bul-
letin, and do the work instructed
by Boeing.
Any crack is found during
inspection of the frame at
STA 312.
-Before further flightContact Boeing to get instructions
for the repair for this service bul-
letin, and do the work instructed
by Boeing.
Any crack is found during
inspection of the frame at
STA 344.
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### Page 46

Group 7:
Table 6: Inspections of the Frame at STA 328 for Cracking
Repeat Inter-
val (Not to
Exceed)
Compliance Time (Whichever
Occurs Later )
ActionCondition
(a) If you do the repair of the frame at STA 328 in accordance with Accomplishment Instructions 3.B.6., then
you can stop repeat inspections. You can do the repair of the frame at STA 328 as an optional preventative
modification in accordance with Accomplishment Instruction 3.B.6.
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### Page 47

Group 2-5:
Table 7: Inspections of the Frame at STA 344 for Cracking and Optional Inspections of the Adjacent
Fuselage Skin for Cracking
Repeat Inter-
val (Not to
Exceed)
Compliance Time (Whichever
Occurs Later )
ActionCondition
4,500 flight
cycles until
Option 1 or
Option 2 is
started. (a)
Within 2,200
flight cycles af-
ter the original
issue date of
this Service
Bulletin.
Before 20,000
total airplane
flight cycles.
Do detailed inspection of the
frame at STA 344 for cracking in
accordance with Accomplishment
Instructions 3.B.3.
Airplanes that have less
than 28,300 total flight cy-
cles at the original issue
date of this Service Bulletin.
--And do one of the options that
follow:
OPTION 1: (b)
2,200 flight
cycles (a)
-Before 35,000
total flight cy-
cles but not to
exceed 4,500
flight cycles
from the last in-
spection.
Do detailed inspection of the
frame at STA 344 for cracking in
accordance with Accomplishment
Instructions 3.B.3.
OPTION 2: (b)
4,500 flight
cycles (a)
-Before 35,000
total flight cy-
cles but not to
exceed 4,500
flight cycles
from the last in-
spection.
Do detailed inspection of the
frame at STA 344 for cracking in
accordance with Accomplishment
Instructions 3.B.3.
1,250 flight
cycles. (c)
(d)
-Before 35,000
total flight cy-
cles but not to
exceed 4,500
flight cycles
from the last in-
spection. (c)
Do external detailed and eddy
current inspections of the fuselage
skin for cracking in accordance
with Accomplishment Instructions
3.B.4.
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### Page 48

Group 2-5:
Table 7: Inspections of the Frame at STA 344 for Cracking and Optional Inspections of the Adjacent
Fuselage Skin for Cracking
Repeat Inter-
val (Not to
Exceed)
Compliance Time (Whichever
Occurs Later )
ActionCondition
--Do one of the options that follow:Airplanes that have 28,300
total flight cycles or more
but less than 32,800 total
flight cycles at the original
issue date of this Service
Bulletin
OPTION 1: (b)
2,200 flight
cycles (a)
Within 2,200
flight cycles af-
ter the original
issue date of
this Service
Bulletin.
-Do detailed inspection of the
frame at STA 344 for cracking in
accordance with Accomplishment
Instructions 3.B.3.
OPTION 2: (b)
4,500 flight
cycles (a)
Within 4,500
flight cycles af-
ter the original
issue date of
this Service
Bulletin.
-Do detailed inspection of the
frame at STA 344 for cracking in
accordance with Accomplishment
Instructions 3.B.3.
1,250 flight
cycles. (c)
(d)
Within 2,200
flight cycles af-
ter the original
issue date of
this Service
Bulletin. (c)
-Do external detailed and eddy
current inspections of the fuselage
skin for cracking in accordance
with Accomplishment Instructions
3.B.4.
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### Page 49

Group 2-5:
Table 7: Inspections of the Frame at STA 344 for Cracking and Optional Inspections of the Adjacent
Fuselage Skin for Cracking
Repeat Inter-
val (Not to
Exceed)
Compliance Time (Whichever
Occurs Later )
ActionCondition
--Do one of the options that follow:Airplanes that have 32,800
total flight cycles or more at
the original issue date of
this Service Bulletin.
OPTION 1: (b)
2,200 flight
cycles (a)
Within 1,250
flight cycles af-
ter the original
issue date of
this Service
Bulletin.
Before 35,000
total flight cy-
cles.
Do detailed inspection of the
frame at STA 344 for cracking in
accordance with Accomplishment
Instructions 3.B.3.
Option 2: (b)
4,500 flight
cycles (a)
Within 1,250
flight cycles af-
ter the original
issue date of
this Service
Bulletin.
Before 35,000
total flight cy-
cles.
Do detailed inspection of the
frame at STA 344 for cracking in
accordance with Accomplishment
Instructions 3.B.3.
1,250 flight
cycles. (c)
(d)
Within 1,250
flight cycles af-
ter the original
issue date of
this Service
Bulletin. (c)
Before 35,000
total flight cy-
cles. (c)
Do external detailed and eddy
current inspections of the fuselage
skin for cracking in accordance
with Accomplishment Instructions
3.B.4.
-Before further flightContact Boeing to get instructions
for the repair for this service bul-
letin, and do the work instructed
by Boeing.
Any crack is found during
inspections of the frame at
STA 344.
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### Page 50

Group 2-5:
Table 7: Inspections of the Frame at STA 344 for Cracking and Optional Inspections of the Adjacent
Fuselage Skin for Cracking
Repeat Inter-
val (Not to
Exceed)
Compliance Time (Whichever
Occurs Later )
ActionCondition
-Before further flight.Repair the fuselage skin in accor-
dance with Accomplishment In-
structions 3.B.7.
Any crack is found during
inspections of the fuselage
skin and you did not do in-
spections of the frame at
STA 328 and the frame at
STA 360 at the time that
you found the crack in the
fuselage skin.
-
Do detailed and eddy current in-
spections of the frame at STA 328
for cracking or a severed frame
web in accordance with Accom-
plishment Instruction 3.B.3. Do the
actions in accordance with Para-
graph 1.E., Compliance, Table 4
for the conditions found.
-
Do detailed and eddy current in-
spections of the frame at STA 360
for cracking or a severed frame
web in accordance with Accom-
plishment Instruction 3.B.3. Do the
actions in accordance with Para-
graph 1.E., Compliance, Table 8
for the conditions found.
-Before further flight.Repair the fuselage skin in accor-
dance with Accomplishment In-
structions 3.B.7.
Any crack is found during
inspections of the fuselage
skin and you did do inspec-
tions of the frame at STA
328 and the frame at STA
360 at the time that you
found the crack in the fuse-
lage skin.
(a) If you do both of the actions that follow, then you can stop repeat inspections of the frame at STA 344:
1 - Do the optional preventative modification of the frame at STA 360 in accordance with Accomplishment
Instructions 3.B.5.
2 - Do the repair of the frame at STA 328 in accordance with Accomplishment Instructions 3.B.6.
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### Page 51

Group 2-5:
Table 7: Inspections of the Frame at STA 344 for Cracking and Optional Inspections of the Adjacent
Fuselage Skin for Cracking
Repeat Inter-
val (Not to
Exceed)
Compliance Time (Whichever
Occurs Later )
ActionCondition
(b) It is acceptable to change inspection procedures from Option 1 to Option 2 or from Option 2 to Option 1
if you do as follows:
1 - If the inspection procedure is being changed from Option 1 to Option 2, then the first Option 2 inspections
(external skin and internal frame) must be done within 2,200 flight cycles after the most recent Option 1
inspection. The Option 2 repeat inspections that follow must be done at the Option 2 repeat intervals in
accordance with Paragraph 1.E., Compliance, Table 7.
2 - If the inspection procedure is being changed from Option 2 to Option 1, then the first Option 1 inspection
must be done within 1,250 flight cycles after the most recent Option 2 inspection (external skin or internal
frame). The Option 1 repeat inspections that follow must be done at the Option 1 repeat intervals in accor-
dance with Paragraph 1.E., Compliance, Table 7.
(c) It is not necessary to inspect the area under an external fuselage skin repair that is installed in accordance
with Accomplishment Instruction 3.B.4. If the repair is not installed in accordance with Accomplishment
Instruction 3.B.4, then do an internal inspection of the area under the external fuselage skin repair in ac-
cordance with Accomplishment Instruction 3.B.4.
(d) If you do both of the actions that follow, then you can stop repeat inspections of the fuselage skin in accor-
dance with this service bulletin:
1 - Do the optional preventative modification of the frame at STA 360 in accordance with Accomplishment
Instructions 3.B.5.
2 - Do the repair of the frame at STA 328 in accordance with Accomplishment Instructions 3.B.6.
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### Page 52

Group 2-5:
Table 8: Inspections of the Frame at STA 360 for Cracking and Optional Inspections of the Adjacent
Fuselage Skin for Cracking
Repeat Inter-
val (Not to
Exceed)
Compliance Time (Whichever
Occurs Later )
ActionCondition
4,500 flight
cycles until
Option 1 or
Option 2 is
started. (a)
Within 2,200
flight cycles af-
ter the original
issue date of
this Service
Bulletin.
Before 20,000
total airplane
flight cycles.
Do detailed and eddy current in-
spections of the frame at STA 360
for cracking or a severed frame
web in accordance with Accom-
plishment Instructions 3.B.3.
Airplanes that have less
than 28,300 total flight cy-
cles at the original issue
date of this Service Bulletin.
--And do one of the options that
follow:
OPTION 1: (b)
2,200 flight
cycles (a)
-Before 35,000
total flight cy-
cles but not to
exceed 4,500
flight cycles
from the last in-
spection.
Do detailed and eddy current in-
spections of the frame at STA 360
for cracking or a severed frame
web in accordance with Accom-
plishment Instructions 3.B.3.
OPTION 2: (b) (c)
4,500 flight
cycles (a)
-Before 35,000
total flight cy-
cles but not to
exceed 4,500
flight cycles
from the last in-
spection.
Do detailed and eddy current in-
spections of the frame at STA 360
for cracking or a severed frame
web in accordance with Accom-
plishment Instructions 3.B.3.
1,250 flight
cycles. (d)
(e)
-Before 35,000
total flight cy-
cles but not to
exceed 4,500
flight cycles
from the last in-
spection. (d)
Do external detailed and eddy
current inspections of the fuselage
skin for cracking in accordance
with Accomplishment Instructions
3.B.4.
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### Page 53

Group 2-5:
Table 8: Inspections of the Frame at STA 360 for Cracking and Optional Inspections of the Adjacent
Fuselage Skin for Cracking
Repeat Inter-
val (Not to
Exceed)
Compliance Time (Whichever
Occurs Later )
ActionCondition
--Do one of the options that follow:Airplanes that have 28,300
total flight cycles or more
but less than 32,800 total
flight cycles at the original
issue date of this Service
Bulletin.
OPTION 1: (b)
2,200 flight
cycles (a)
Within 2,200
flight cycles af-
ter the original
issue date of
this Service
Bulletin.
-Do detailed and eddy current in-
spections of the frame at STA 360
for cracking or a severed frame
web in accordance with Accom-
plishment Instructions 3.B.3.
OPTION 2: (b) (c)
4,500 flight
cycles (a)
Within 4,500
flight cycles af-
ter the original
issue date of
this Service
Bulletin.
-Do detailed and eddy current in-
spections of the frame at STA 360
for cracking or a severed frame
web in accordance with Accom-
plishment Instructions 3.B.3.
1,250 flight
cycles. (d)
(e)
Within 2,200
flight cycles af-
ter the original
issue date of
this Service
Bulletin. (d)
-Do external detailed and eddy
current inspections of the fuselage
skin for cracking in accordance
with Accomplishment Instructions
3.B.4.
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### Page 54

Group 2-5:
Table 8: Inspections of the Frame at STA 360 for Cracking and Optional Inspections of the Adjacent
Fuselage Skin for Cracking
Repeat Inter-
val (Not to
Exceed)
Compliance Time (Whichever
Occurs Later )
ActionCondition
--Do one of the options that follow:Airplanes that have 32,800
total flight cycles or more at
the original issue date of
this Service Bulletin.
OPTION 1: (b)
2,200 flight
cycles (a)
Within 1,250
flight cycles af-
ter the original
issue date of
this Service
Bulletin.
Before 35,000
total flight cy-
cles.
Do detailed and eddy current in-
spections of the frame at STA 360
for cracking or a severed frame
web in accordance with Accom-
plishment Instructions 3.B.3.
OPTION 2: (b) (c)
4,500 flight
cycles (a)
Within 1,250
flight cycles af-
ter the original
issue date of
this Service
Bulletin.
Before 35,000
total flight cy-
cles.
Do detailed and eddy current in-
spections of the frame at STA 360
for cracking or a severed frame
web in accordance with Accom-
plishment Instructions 3.B.3.
1,250 flight
cycles. (d)
(e)
Within 1,250
flight cycles af-
ter the original
issue date of
this Service
Bulletin. (d)
Before 35,000
total flight cy-
cles. (d)
Do external detailed and eddy
current inspections of the fuselage
skin for cracking in accordance
with Accomplishment Instructions
3.B.4.
-Before further flightContact Boeing to get instructions
for the repair for this service bul-
letin, and do the work instructed
by Boeing.
Any crack is found during
inspections of the frame at
STA 360.
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### Page 55

Group 2-5:
Table 8: Inspections of the Frame at STA 360 for Cracking and Optional Inspections of the Adjacent
Fuselage Skin for Cracking
Repeat Inter-
val (Not to
Exceed)
Compliance Time (Whichever
Occurs Later )
ActionCondition
-Before further flightContact Boeing to get instructions
for the repair for this service bul-
letin, and do the work instructed
by Boeing.
A severed frame web is
found during inspections of
the frame at STA 360 and
you did not do inspections
of the fuselage skin at the
time that you found the
severed frame web.
-
Do a detailed inspection of the
adjacent frame at STA 344 for
cracking in accordance with Ac-
complishment Instruction 3.B.3.
-
Do a detailed inspection of the
adjacent frame at STA 380 for
cracking in accordance with Ac-
complishment Instruction 3.B.3.
-
Do external detailed and eddy
current inspections of the fuselage
skin for cracking in accordance
with Accomplishment Instruction
3.B.4.
-Before further flightContact Boeing to get instructions
for the repair for this service bul-
letin, and do the work instructed
by Boeing.
A severed frame web is
found during inspections of
the frame at STA 360 and
you did do inspections of
the fuselage skin at the time
that you found the severed
frame web.
-
Do a detailed inspection of the
adjacent frame at STA 344 for
cracking in accordance with Ac-
complishment Instruction 3.B.3.
-
Do a detailed inspection of the
adjacent frame at STA 380 for
cracking in accordance with Ac-
complishment Instruction 3.B.3.
-Before further flightContact Boeing to get instructions
for the repair for this service bul-
letin, and do the work instructed
by Boeing.
Any crack is found during
inspection of the frame at
STA 344.
-Before further flightContact Boeing to get instructions
for the repair for this service bul-
letin, and do the work instructed
by Boeing.
Any crack is found during
inspection of the frame at
STA 380.
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### Page 56

Group 2-5:
Table 8: Inspections of the Frame at STA 360 for Cracking and Optional Inspections of the Adjacent
Fuselage Skin for Cracking
Repeat Inter-
val (Not to
Exceed)
Compliance Time (Whichever
Occurs Later )
ActionCondition
-Before further flight.Repair the fuselage skin in accor-
dance with Accomplishment In-
structions 3.B.7.
Any crack is found during
inspections of the fuselage
skin and you did not do in-
spections of the frame at
STA 328 and the frame at
STA 360 at the time that
you found the crack in the
fuselage skin.
-
Do detailed and eddy current in-
spections of the frame at STA 328
for cracking or a severed frame
web in accordance with Accom-
plishment Instruction 3.B.3. Do the
actions in accordance with Para-
graph 1.E., Compliance, Table 4
for the conditions found.
-
Do detailed and eddy current in-
spections of the frame at STA 360
for cracking or a severed frame
web in accordance with Accom-
plishment Instruction 3.B.3. Do the
actions in accordance with Para-
graph 1.E., Compliance, Table 8
for the conditions found.
-Before further flight.Repair the fuselage skin in accor-
dance with Accomplishment In-
structions 3.B.7.
Any crack is found during
inspections of the fuselage
skin and you did do inspec-
tions of the frame at STA
328 and the frame at STA
360 at the time that you
found the crack in the fuse-
lage skin.
(a) If you do the optional preventative modification of the frame at STA 360 in accordance with Accomplishment
Instructions 3.B.5, then you can stop repeat inspections of the frame at STA 360.
(b) It is acceptable to change inspection procedures from Option 1 to Option 2 or from Option 2 to Option 1
if you do as follows:
1 - If the inspection procedure is being changed from Option 1 to Option 2, then the first Option 2 inspections
(external skin and internal frame) must be done within 2,200 flight cycles after the most recent Option 1
inspection. The Option 2 repeat inspections that follow must be done at the Option 2 repeat intervals in
accordance with Paragraph 1.E., Compliance, Table 8.
2 - If the inspection procedure is being changed from Option 2 to Option 1, then the first Option 1 inspection
must be done within 1,250 flight cycles after the most recent Option 2 inspection (external skin or internal
frame). The Option 1 repeat inspections that follow must be done at the Option 1 repeat intervals in accor-
dance with Paragraph 1.E., Compliance, Table 8.
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### Page 57

Group 2-5:
Table 8: Inspections of the Frame at STA 360 for Cracking and Optional Inspections of the Adjacent
Fuselage Skin for Cracking
Repeat Inter-
val (Not to
Exceed)
Compliance Time (Whichever
Occurs Later )
ActionCondition
(c) It is recommended that actions in Option 2 on the frames at STA 360 and STA 344 are done concurrently.
(d) It is not necessary to inspect the area under an external fuselage skin repair that is installed in accordance
with Accomplishment Instruction 3.B.4. If the repair is not installed in accordance with Accomplishment
Instruction 3.B.4, then do an internal inspection of the area under the external fuselage skin repair in ac-
cordance with Accomplishment Instruction 3.B.4.
(e) If you do both of the actions that follow, then you can stop repeat inspections of the fuselage skin in accor-
dance with this service bulletin:
1 - Do the optional preventative modification of the frame at STA 360 in accordance with Accomplishment
Instructions 3.B.5.
2 - Do the repair of the frame at STA 328 in accordance with Accomplishment Instructions 3.B.6.
Group 2, 4:
Table 9: Inspections of the Frame at STA 380 for Cracking
Repeat Inter-
val (Not to
Exceed)
Compliance Time (Whichever
Occurs Later )
ActionCondition
10,000 flight
cycles
Within 4,500
flight cycles af-
ter the original
issue date of
this Service
Bulletin.
Before 30,000
total flight cy-
cles.
Do detailed and eddy current in-
spections of the frame at STA 380
for cracking or a severed frame
web in accordance with Accom-
plishment Instructions 3.B.3.
All airplanes.
-Before further flightContact Boeing to get instructions
for the repair for this service bul-
letin, and do the work instructed
by Boeing.
Any crack is found during
inspections of the frame at
STA 380.
-Before further flightContact Boeing to get instructions
for the repair and additional inspec-
tions for this service bulletin, and
do the work instructed by Boeing.
A severed frame web is
found during inspections of
the frame at STA 380.
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### Page 58

Group 3, 5:
Table 10: Inspections of the Frame at STA 380 for Cracking
Repeat Inter-
val (Not to
Exceed)
Compliance Time (Whichever
Occurs Later )
ActionCondition
5,500 flight
cycles
Within 4,500
flight cycles af-
ter the original
issue date of
this Service
Bulletin.
Before 30,000
total flight cy-
cles.
Do detailed and eddy current in-
spections of the frame at STA 380
for cracking or a severed frame
web in accordance with Accom-
plishment Instructions 3.B.3.
All airplanes.
-Before further flightContact Boeing to get instructions
for the repair for this service bul-
letin, and do the work instructed
by Boeing.
Any crack is found during
inspections of the frame at
STA 380.
-Before further flightContact Boeing to get instructions
for the repair and additional inspec-
tions for this service bulletin, and
do the work instructed by Boeing.
A severed frame web is
found during inspections of
the frame at STA 380.
Group 2-5:
Table 11: Optional Preventative Modification of the frame at STA 360
Repeat Inter-
val (Not to
Exceed)
Compliance Time (Whichever
Occurs Later )
ActionCondition
-Before further flight.Contact Boeing to get instructions
for the repair for this service bul-
letin, and do the work instructed
by Boeing.
Any crack is found during
the pre-modification inspec-
tions of the frame at STA
360.
-Before further flight.Contact Boeing to get repair in-
structions for this service bulletin,
and do the work instructed by
Boeing.
The tool hole, or the insula-
tion blanket stud hole, or ei-
ther of the two end fastener
rivet holes are larger than
specified in Accomplish-
ment Instructions 3.B.5.
Group 2-7:
Table 12: Repair of the Frame at STA 328
Repeat Inter-
val (Not to
Exceed)
Compliance Time (Whichever
Occurs Later )
ActionCondition
-Before further flight.Contact Boeing to get instructions
for the repair for this service bul-
letin, and do the work instructed
by Boeing.
Any crack is found during
the pre-repair inspection of
the frame at STA 328.
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### Page 59

Group 2-5:
Table 13: Damage Tolerance Post-Modification Inspections of the Frame at STA 360 for Cracking
Repeat Inter-
val (Not to
Exceed)
Compliance Time (Whichever
Occurs Later )
ActionCondition
2,300 flight
cycles
Within 73,000
flight cycles af-
ter optional
preventative
modification
has been
done.
-Do the damage tolerance post-
modification detailed and eddy
current inspections of the frame
at STA 360 for cracking in accor-
dance with Accomplishment In-
structions 3.B.8.
The optional preventative
modification of frame at
STA 360 has been done in
accordance with Accom-
plishment Instructions
3.B.5.
-Before further flight.Contact Boeing to get instructions
for the repair for this service bul-
letin, and do the work instructed
by Boeing.
Any crack is found during
the damage tolerance post-
modification inspections of
the frame at STA 360.
Group 2-7:
Table 14: Damage Tolerance Post-Repair Inspections of the Frame at STA 328 for Cracking
Repeat Inter-
val (Not to
Exceed)
Compliance Time (Whichever
Occurs Later )
ActionCondition
10,000 flight
cycles
Within 75,000
flight cycles af-
ter the repair
has been in-
stalled
-Do damage tolerance post-repair
detailed and eddy current inspec-
tions of the frame at STA 328 for
cracking in accordance with Ac-
complishment Instructions 3.B.9.
A repair has been installed
on the frame at STA 328 in
accordance with Accom-
plishment Instructions
3.B.6.
-Before further flight.Contact Boeing to get instructions
for the repair for this service bul-
letin, and do the work instructed
by Boeing.
Any crack is found during
the damage tolerance post-
repair inspections of the
frame at STA 328.
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### Page 60

Group 2-5:
Table 15: Damage Tolerance Post-Repair Inspections of the Fuselage Skin for Cracking
Repeat Inter-
val (Not to
Exceed)
Compliance Time (Whichever
Occurs Later )
ActionCondition
Continue to
do repeat in-
spections in
accordance
with 737-
100/200
SRM 53-30-
3 Figure 48,
or 737-300
SRM 53-00-
01 Repair
31, or 737-
400 SRM 53-
00-01 Repair
31, or 737-
500 SRM 53-
00-01 Repair
31.
Within 60,000
flight cycles af-
ter repair of the
fuselage skin
has been
done.
-Do damage tolerance post-repair
inspections of the fuselage skin
for cracking in accordance with
Accomplishment Instructions
3.B.10.
The fuselage skin has been
repaired in accordance with
Accomplishment Instruc-
tions 3.B.7.
-Before further flight.Contact Boeing to get instructions
for the repair for this service bul-
letin, and do the work instructed
by Boeing.
Any crack is found during
the damage tolerance post-
repair inspections of the
fuselage skin.
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.
The Manager of the FAA Seattle Aircraft Certification Office approves accomplishment of the fuselage
skin inspection methods and repeat inspection intervals for Option 2 of Tables 4, 5, 7 and 8 as described
in Paragraph 1.E, Compliance, of this service bulletin as an alternative method of compliance to the
inspections of these areas required by paragraphs (h) and (s) of AD 2013-18-08. If a frame is modified
or repaired in accordance with Paragraph 1.E, Compliance, of this service bulletin, then inspections
for these areas required by AD 2013-18-08 must be accomplished. All provisions of AD 2013-18-08
that are not specifically referenced remain fully applicable and must be complied with accordingly.
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