# Boeing Alert Service Bulletin 737-53A1214: Revision 5 - Rights: © The Boeing Company. Filed by the FAA in regulations.gov docket FAA-2015-6538; AD 2016-20-02 incorporates this document by reference. Not covered by OpenAirDocs’ CC0 dedication. - Document: [Boeing Alert Service Bulletin 737-53A1214](https://openairdocs.org/service-documents/boeing/737-53a1214.md) - Title as filed: U.S. DOT/FAA - SB-737-53A1214, Rev. 5 - Pages: 77 - PDF: https://openairdocs.org/files/sha256/6e/6f/6e6ffdf5394903bb86714e40a631a7dd99c2ba919c85644b1400dd91383d1cc8 - Page: https://openairdocs.org/service-documents/boeing/737-53a1214/file/6e6ffdf53949 ## Text Some pages are OCR from a scan. OCR can misread letters and numbers. Each page's text from the PDF; open the PDF at a page with #page=N. ### Page 1 Commercial Airplanes 737 Service Bulletin ALERT Number: 737-53A1214 Original Issue: June 17, 1999 Revision 5: January 30, 2015 ATA System: 5311 SUBJECT: FUSELAGE - Body Station 1016 Aft Pressure Bulkhead Web Cracks - Inspection and Repair Export of this technology is controlled under the United States Export Administration Regulations (EAR) (15 CFR 300-774). An export license may be required before it is used for development, production or use by foreign persons from specific countries. The controller of this data has the individual responsibility to abide by all export laws. 9E991ECCN: BOEING PROPRIETARY, CONFIDENTIAL AND/OR TRADE SECRET Copyright © 1999 Boeing. Unpublished Work. All Rights Reserved. Treatment of this document and its content is governed by contract with Boeing. Rights to use this document are licensed on a per aircraft basis and such rights may not be transferable. For more information, contact The Boeing Company. Boeing, the Boeing signature, the Boeing symbol, 707, 717, 727, 737, 747, 757, 767, 777, 787, Dreamliner, BBJ, DC-8, DC-9, DC-10, KC-10, KC-46, KDC-10, MD-10, MD-11, MD-80, MD-88, MD-90, P-8, Poseidon and Boeing liveries are all trademarks owned by The Boeing Company; and no trademark license is granted in connection with this document unless provided in writing by Boeing. Original Issue: June 17, 1999 737-53A1214Revision 5: January 30, 2015 1 of 77 7.0 ### Page 2 Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: June 17, 1999 737-53A1214Revision 5: January 30, 2015 2 of 77 BOEING SERVICE BULLETIN 737-53A1214 ALERTALERT BLANK PAGE ### Page 3 Table of Contents Revision Transmittal Sheet ............................................ 5 Summary ...................................................... 7 1. PLANNING INFORMATION ........................................ 1 1 A. Effectivity ............................................... 1 1 1. Airplanes ............................................ 1 1 2. Spares Affected ........................................ 2 4 B. Concurrent Requirements ...................................... 2 4 C. Reason ................................................ 2 4 D. Description .............................................. 2 6 E. Compliance .............................................. 2 7 F. Approval ............................................... 3 8 G. Manpower .............................................. 3 9 H. Weight and Balance Changes .................................... 4 1 I. Electrical Load Data ......................................... 4 1 J. References .............................................. 4 1 1. Existing Data: ......................................... 4 1 2. Data Supplied with this Service Bulletin: ........................... 4 2 3. Installation Drawings Used in the Preparation of this Service Bulletin: ........... 4 2 K. Publications Affected ........................................ 4 2 L. Interchangeability and Intermixability of Parts ........................... 4 2 M. Software Accomplishment Summary ................................ 4 2 2. MATERIAL INFORMATION ........................................ 4 3 A. Material - Price and Availability ................................... 4 3 B. Industry Support Information .................................... 4 3 C. Parts Necessary for Each Airplane ................................. 4 3 1. Kits/Parts: ........................................... 4 3 2. Parts and Materials Supplied by the Operator: ........................ 4 3 3. Parts Modified and Reidentified: ............................... 4 3 4. Parts Removed and Not Replaced: .............................. 4 3 D. Parts Necessary to Change Spares ................................. 4 3 E. Special Tooling - Price and Availability ............................... 4 3 F. Special Tooling Necessary to do this Service Bulletin ....................... 4 3 3. ACCOMPLISHMENT INSTRUCTIONS .................................. 4 5 A. GENERAL INFORMATION ..................................... 4 5 B. WORK INSTRUCTIONS ....................................... 4 6 FIGURE 1: LFEC INSPECTION OF THE WEB AT THE "Y" CHORD IN THE UPPER BULKHEAD FROM STRINGER S-15L TO S-15R ................................. 5 2 FIGURE 2: HFEC INSPECTION OF THE WEB AT THE "Y" CHORD IN THE UPPER BULKHEAD FROM STRINGER S-15L TO S-15R ................................. 5 4 FIGURE 3: ONE-TIME NDT INSPECTION OF WEB AT THE OUTER CIRCUMFERENTIAL TEAR STRAP .................................................. 5 6 FIGURE 4: NDT INSPECTION OF WEB AT THE "Y" CHORD IN THE LOWER BULKHEAD FROM STRINGER S-15LTO S-15R .................................. 5 8 FIGURE 5: DETAILED INSPECTION FOR OIL-CAN DAMAGE IN THE BULKHEAD WEB ...... 6 0 FIGURE 6: NDT INSPECTION OF THE DOME CAP AT THE CENTER OF THE BULKHEAD ..... 6 2 Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: June 17, 1999 737-53A1214Revision 5: January 30, 2015 3 of 77 BOEING SERVICE BULLETIN 737-53A1214 ALERTALERT ### Page 4 FIGURE 7: NDT INSPECTION OF THE FORWARD FLANGE OF THE "Z" STIFFENER AT THE DOME C A P............................................... 6 4 Appendix A: OBSOLETE 737-100/200 SRM 53-10-4 FIGURE 3 OR 737-300/400/500 53-80-08 REPAIR 1 - TYPICAL REPAIR FOR DAMAGE TO WEB AND STRAP .................. 6 7 Appendix B: OBSOLETE 737-100/200 SRM 53-10-4 FIGURE 3 OR 737-300/400/500 53-80-08 REPAIR 1 - TYPICAL REPAIR FOR DAMAGE TO WEB ......................... 6 9 Appendix C: OBSOLETE 737-100/200 SRM 53-10-4 FIGURE 5 OR 737-300/400/500 SRM 53-80-08 REPAIR 2 ................................................. 7 0 Appendix D: OBSOLETE 737-100/200 SRM 53-10-4 FIGURE 12 OR 737-300/400/500 SRM 53-80-08 REPAIR 4 ................................................. 7 2 Appendix E: OBSOLETE 737-100/200 SRM 53-10-4 FIGURE 13 OR 737-300/400/500 SRM 53-80-08 REPAIR 5 ................................................. 7 5 Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: June 17, 1999 737-53A1214Revision 5: January 30, 2015 4 of 77 BOEING SERVICE BULLETIN 737-53A1214 ALERTALERT ### Page 5 Commercial Airplanes 737 Service Bulletin ALERT Revision Transmittal SheetNumber: 737-53A1214Original Issue: June 17, 1999 Revision 5: January 30, 2015 ATA System: 5311 SUBJECT: FUSELAGE - Body Station 1016 Aft Pressure Bulkhead Web Cracks - Inspection and Repair This revision includes all pages of the service bulletin. COMPLIANCE INFORMATION RELATED TO THIS REVISION Group 1: No more work is necessary on the airplane(s) changed or inspected in accordance with Revision 4 of this service bulletin. These airplanes will reach their limit of validity prior to the compliance time for the inspections added by this service bulletin revision. Group 2: More work is necessary on the airplane(s) changed or inspected in accordance with Revision 4 of this service bulletin. Beginning at 76,000 total flight cycles, the repeat inspection interval is reduced for Non-Destructive Testing (NDT) inspections of the web at the "Y" Chord. Federal Aviation Administration (FAA) Airworthiness Directive AD 2012-18-13 R1 is related to this service bulletin. The effective date of AD 2012-18-13 R1 is June 13, 2013. The Federal Aviation Administration (FAA) will possibly release an additional Airworthiness Directive related to this service bulletin. The Airworthiness Directive will make the compliance tasks and times given in this service bulletin mandatory. REASON FOR REVISION This revision is sent to incorporate a Widespread Fatigue Damage (WFD) analysis for Group 2 airplanes. Beginning at 76,000 total flight cycles, the repeat inspection interval is decreased for Non-Destructive Testing (NDT) inspections of the web at the "Y" Chord. The data given in Alternative Method of Compliance Notice (AMOC) SB 737-53A1214-AMOC-01 is included in this revision. The data given in Alternative Method of Compliance Notice (AMOC) SB 737-53A1214-AMOC-02 is included in this revision. The data given in Global Alternative Method of Compliance Notice (GAMOC) 120S-12-630 is included in this revision. Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: June 17, 1999 737-53A1214Revision 5: January 30, 2015 5 of 77 ### Page 6 These sections were changed: 1. In Summary, changed Background and Compliance. 2. In Paragraph 1.A., Effectivity, Airplane line numbers 2566 to 3132 are moved from Group 1 into new Group 2. 3. In Paragraph 1.C., Reason, added Service Related Problem (SRP) 737-SRP-53-0417. 4. In Paragraph 1.E., Compliance, added the following: – Federal Aviation Administration (FAA) Airworthiness Directive AD 2012-18-13 R1 – Statement that the FAA will possibly release an additional Airworthiness Directive (AD) – Statement to do required actions in accordance with Paragraph 3. Accomplishment Instructions – Note pertaining to Limit of Validity of Line Number 1-291 airplanes – Group 1 heading to Table 1 and Table 2 – Table 9 to Table 11 for Group 2 airplanes 5. In Paragraph 1.F., Approval, changed to add AD 2012-18-13 R1. 6. In Paragraph 1.J., References, added Service Related Problem (SRP) 737-SRP-53-0417 and AD 2012-18-13 R1. 7. Added Paragraph 1.M., Software Accomplishment Summary. 8. In Paragraph 3.B., Work Instructions, changed the following: – In Parts II-V, clarified repeat inspections are applicable to unrepaired structure. – In PART VI, changed Part VI and deleted Step 2. 9. In Figure 3, changed Step Table footnote (a). 10. In Appendix B, changed to remove inspection of repair plate. Vertical lines are put on the left edge of each page, except in Paragraph 1.A., Effectivity and format changes, to show the location of all content changes. Pages with no vertical lines have no changes. REVISION HISTORY June 17, 1999Original Issue: June 22, 2000Revision 1: May 24, 2001Revision 2: January 19, 2011Revision 3: December 16, 2011Revision 4: January 30, 2015Revision 5: Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: June 17, 1999 737-53A1214Revision 5: January 30, 2015 6 of 77 BOEING SERVICE BULLETIN 737-53A1214 ALERTALERT ### Page 7 Commercial Airplanes 737 Service Bulletin ALERT SummaryNumber: 737-53A1214Original Issue: June 17, 1999 Revision 5: January 30, 2015 ATA System: 5311 SUBJECT: FUSELAGE - Body Station 1016 Aft Pressure Bulkhead Web Cracks - Inspection and Repair THIS BULLETIN IS SENT TO THE OPERATORS OF RECORD OF THE AIRPLANES SHOWN IN PARAGRAPH 1.A., EFFECTIVITY. IF AN AIRPLANE HAS BEEN LEASED OR SOLD, SEND THIS SERVICE BULLETIN TO THE NEW OPERATOR. IF APPLICABLE SPARES HAVE BEEN SOLD, SEND THIS SERVICE BULLETIN TO THE NEW OWNER. CONCURRENT REQUIREMENTS None. BACKGROUND Cracks have been reported in four general areas on the aft pressure bulkhead: cracks in the web at the web-to-"Y" chord interface; cracks in the web at the outer circumferential tear strap; cracks in the web near the dome cap; and cracks in the "Z" stiffeners near the dome cap. Undetected cracking could result in loss of ability to maintain cabin pressure, rapid decompression of the airplane, and significant structural damage to the aft fuselage. Cracks reported in the web at the web-to-"Y" chord interface occurred in the aft row of fasteners connecting the web to the "Y" chord. In all of the cases, the cracks ran in the circumferential direction. Most of the cracks have been at Stringer S-6L and S-6R, but there have been reports of cracks at other locations. The airplanes had accumulated between 22,966 and 68,000 flight cycles and between 45,500 and 61,000 flight hours. There have been two reports of cracking in the bulkhead web at the outer circumferential tear strap. The airplanes had 21,246 and 26,162 flight cycles and 17,500 and 24,132 flight hours respectively. Since revision 2 of this service bulletin, there have been reports of cracking in the center of the web near the dome cap. The cracks occurred at the center of the bulkhead at the end of the web gore sections. The airplanes had accumulated more than 30,000 flight cycles and 36,000 flight hours. There have also been two reports of cracks located on the "Z" stiffeners forward flange at the attach location to the dome cap pan. The cracks extended from the outboard fastener hole and ran circumferentially. Boeing Structural Item Interim Advisory (SIIA) SIIA 737-52 and SIIA 737-269 are related to this service bulletin. Boeing Service Related Problem (SRP) 737-SRP-53-0109, 737-SRP-53-0116, 737-SRP-53-0155, and 737-SRP-53-0417 are related to this service bulletin. This table is provided to operators for planning purposes only. Refer to the applicable sections for more information. Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: June 17, 1999 737-53A1214Revision 5: January 30, 2015 7 of 77 ### Page 8 ReferenceAffectedPlanning Data Paragraph 1.A.2., Spares AffectedNoSpares Affected Paragraph 1.E., Compliance and Paragraph 1.F., Approval YesAD Related Paragraph 1.H., Weight and Balance ChangesNoWeight and Balance Change Paragraph 1.I., Electrical Load DataNoElectrical Load Changed Paragraph 1.K., Publications AffectedNoPublications Affected Paragraph 1.K., Publications AffectedNoAirplane Flight Operations Affected (Flight Crew Operations Manual and/or FAA Approved Air- plane Flight Manual) Paragraph 2.C.1., Kits/PartsNoKits/Parts Required Paragraph 2.C.2., Parts and Materials Supplied by the Operator NoOperator Supplied Parts/Material Paragraph 2.F., Special Tooling Necessary to do this Service Bulletin NoSpecial Tooling Required ACTION Get access to the forward or aft side of the aft pressure bulkhead and do a Non-Destructive Test (NDT) inspection for any cracking in the web at the "Y" chord. If damage is found from the aft side, get access to the forward side of the bulkhead and do a High Frequency Eddy Current (HFEC) inspection for any cracking in the web at the "Y" chord for the section of web where the damage was found. If any cracking is found, repair the crack(s) in accordance with the Structural Repair Manual (SRM) or contact Boeing for repair instructions and do the repair. From either side of the bulkhead, do a NDT inspection for any cracking in the web at the outer circumferential tear strap for 360 degrees. Also, do an inspection for oil-canning in the web of the entire bulkhead and do repeat inspections at the times shown in the Compliance Section. If any cracking is found, repair the crack(s) in accordance with the Structural Repair Manual (SRM) or contact Boeing for repair instructions and do the repair. From the aft side of the bulkhead, do a NDT inspection for any cracking in the bulkhead web at the lap joints. Do the inspection from the edge of the gore section at the center of bulkhead to approximately ten inches outboard of the center. Do repeat inspections at the times shown in the Compliance Section. If any cracking is found, repair the crack(s) in accordance with the Structural Repair Manual (SRM) or contact Boeing for repair instructions and do the repair. EFFECTIVITY All 737-100/-200/-200C/-300/-400/-500 Airplanes. Refer to Paragraph 1.A.1., Airplanes, for the list of affected airplanes. COMPLIANCE Federal Aviation Administration (FAA) Airworthiness Directive AD 2012-18-13 R1 is related to this service bulletin. The effective date of AD 2012-18-13 R1 is June 13, 2013. Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: June 17, 1999 737-53A1214Revision 5: January 30, 2015 8 of 77 BOEING SERVICE BULLETIN 737-53A1214 ALERTALERT ### Page 9 The Federal Aviation Administration (FAA) will possibly release an additional Airworthiness Directive related to this service bulletin. This airworthiness directive would make certain compliance tasks and times given in Revision 5 of this service bulletin mandatory for Group 2 airplanes. Refer to Paragraph 1.E., Compliance. INDUSTRY SUPPORT INFORMATION Boeing warranty remedies are not available for the inspection, and/or repair procedures given in this service bulletin. MANPOWER Refer to Paragraph 1.G., Manpower. MATERIAL INFORMATION None. Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: June 17, 1999 737-53A1214Revision 5: January 30, 2015 9 of 77 BOEING SERVICE BULLETIN 737-53A1214 ALERTALERT ### Page 10 (OCR) BOEING SERVICE BULLETIN 737-53A1214 ALERT ALERT NDT INSPECT THE WEB FOR CRACKING AT THE OUTER CIRCUMFERENTIAL TEAR STRAP BL VISUALLY INSPECT THE WEB FOR OIL-CANNING 5-71- -S-7R ACCESS DOOR "Y" CHORD FRAME CHORD S-15L ~S-15R FWD WEB INSPECT THE WEB ALONG THE AFT ROW NDT INSPECT THE OF FASTENERS USING EDDY CURRENT WEB FOR CRACKING AND VISUAL INSPECTION A-A AT THE CENTER OF B—B VIEW LOOKING FORWARD THE BULKHEAD DOME PAN "Z" STIFFENER (TYPICAL) WEB (TYPICAL) FWD NDT INSPECT THE "Z" STIFFENER FLANGE WHERE IT ATTACHES TO THE DOME PAN (24 PLACES) C-C S62272 Original Issue: June 17, 1999 Revision 5: January 30, 2015 PROPRIETARY - Copyright © Unpublished Export Controlled ECCN: 9E991 - BOEING 737-53A1214 Work - See page 1 for details. 10 of 77 ### Page 11 Commercial Airplanes 737 Service Bulletin ALERT Number: 737-53A1214 Original Issue: June 17, 1999 Revision 5: January 30, 2015 ATA System: 5311 SUBJECT: FUSELAGE - Body Station 1016 Aft Pressure Bulkhead Web Cracks - Inspection and Repair THIS BULLETIN IS SENT TO THE OPERATORS OF RECORD OF THE AIRPLANES SHOWN IN PARAGRAPH 1.A., EFFECTIVITY. IF AN AIRPLANE HAS BEEN LEASED OR SOLD, SEND THIS SERVICE BULLETIN TO THE NEW OPERATOR. IF APPLICABLE SPARES HAVE BEEN SOLD, SEND THIS SERVICE BULLETIN TO THE NEW OWNER. 1. PLANNING INFORMATION A. Effectivity 1. Airplanes Refer to Service Bulletin Index D6-19567 Part 3 for Airplane Variable Number, Line Number, and Serial Number data. This service bulletin is for the airplanes shown below. Refer to PRR 35005-229R for data about this change. DESCRIPTIONCONFIGURATIONGROUP 737-100/200/200C/300/400/500 Series Airplanes, Line Numbers 1 - 2565. -1 737-100/200/200C/300/400/500 Series Airplanes, Line Numbers 2566-3132. -2 Airplane Models: 737-100, 737-200, 737-200C, 737-300, 737-400, 737-500 GroupVariable Number 1PA001 - PA022 1PA099 1PA231 - PA232 Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: June 17, 1999 737-53A1214Revision 5: January 30, 2015 11 of 77 ### Page 12 GroupVariable Number 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 - PG586 1PG621 - PG630 1PG651 - PG652 1PG701 - PG705 1PH001 1PH011 - PH013 1PH021 - PH024 1PH701 - PH715 1PH731 - PH732 1PH741 - PH743 1PJ001 - PJ009 1PJ031 - PJ032 1PJ071 - PJ072 1PJ101 - PJ119 1PJ201 - PJ219 1PJ301 - PJ302 1PJ551 - PJ552 2PJ553 - PJ561 2PJ601 - PJ615 Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: June 17, 1999 737-53A1214Revision 5: January 30, 2015 12 of 77 BOEING SERVICE BULLETIN 737-53A1214 ALERTALERT ### Page 13 GroupVariable Number 2PJ811 2PJ816 - PJ817 1PK026 - PK029 1PK041 - PK053 1PK061 - PK070 1PK081 - PK082 1PK091 - PK099 1PK101 - PK103 1PK111 - PK120 1PK141 - PK146 1PK201 - PK204 1PK211 - PK223 1PK231 - PK241 1PK251 - PK258 1PK271 - PK274 1PK281 - PK289 1PK291 1PK301 - PK318 1PK341 1PK351 - PK361 1PK391 1PK431 - PK433 1PK451 - PK452 1PK461 - PK469 1PK495 1PK501 - PK504 1PK511 - PK515 1PK519 1PK521 - PK528 1PK541 - PK565 1PK581 1PK591 - PK599 1PK601 - PK617 Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: June 17, 1999 737-53A1214Revision 5: January 30, 2015 13 of 77 BOEING SERVICE BULLETIN 737-53A1214 ALERTALERT ### Page 14 GroupVariable Number 1PK621 - PK637 1PK641 - PK642 1PK661 - PK666 1PK671 - PK681 1PK691 - PK697 1PK711 - PK716 1PK731 - PK765 1PK771 - PK779 1PK801 - PK804 1PK819 - PK827 1PK830 1PK861 - PK863 1PK871 - PK874 1PK881 - PK884 1PK901 - PK938 1PK971 - PK974 1PL001 - PL028 1PL061 1PL081 1PL101 - PL113 1PL151 1PL171 - PL172 1PL201 - PL203 1PL221 1PL401 - PL417 1PL421 1PL441 1PL451 - PL456 1PL471 1PL491 1PL501 - PL506 1PL551 - PL562 1PL581 Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: June 17, 1999 737-53A1214Revision 5: January 30, 2015 14 of 77 BOEING SERVICE BULLETIN 737-53A1214 ALERTALERT ### Page 15 GroupVariable Number 1PL601 - PL603 1PL611 1PL621 - PL626 1PL631 - PL632 1PL711 - PL712 1PL716 - PL747 1PL756 1PL758 1PL761 - PL770 1PL781 - PL788 1PL793 1PL801 - PL803 1PM001 - PM006 1PM016 - PM017 1PM021 - PM023 1PM051 - PM066 1PM101 - PM119 1PM141 - PM142 1PM171 1PM181 1PM251 - PM255 1PM281 - PM283 1PM381 - PM399 1PM401 - PM417 1PM541 - PM547 2PM548 - PM550 1PM551 - PM564 1PN001 - PN002 1PN021 - PN043 1PN081 - PN086 1PN101 - PN117 1PN131 - PN163 1PN401 - PN420 Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: June 17, 1999 737-53A1214Revision 5: January 30, 2015 15 of 77 BOEING SERVICE BULLETIN 737-53A1214 ALERTALERT ### Page 16 GroupVariable Number 1PN431 - PN433 1PN451 - PN456 1PN471 - PN474 1PN481 1PN491 - PN493 1PN501 - PN502 1PN511 - PN512 1PN521 1PP001 - PP054 1PP101 - PP169 1PP181 - PP199 1PP201 - PP205 1PP221 1PP231 - PP243 1PP281 - PP286 1PP301 - PP305 1PP351 - PP353 1PP376 - PP384 1PP391 - PP393 1PP401 - PP440 1PP471 - PP475 1PP501 - PP517 2PP518 - PP520 1PP521 - PP522 1PP631 - PP634 1PP651 - PP652 1PP671 - PP699 1PP701 - PP733 1PP771 - PP779 1PP801 - PP808 1PP821 - PP827 1PP831 - PP848 1PP851 - PP852 Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: June 17, 1999 737-53A1214Revision 5: January 30, 2015 16 of 77 BOEING SERVICE BULLETIN 737-53A1214 ALERTALERT ### Page 17 GroupVariable Number 1PP861 - PP875 2PP876 - PP877 1PP891 - PP899 1PP901 - PP936 1PP946 - PP948 1PP951 - PP952 1PP961 - PP967 1PP981 - PP991 1PP993 1PQ001 - PQ016 1PQ026 - PQ041 1PQ051 - PQ092 1PQ101 - PQ199 1PQ201 - PQ202 1PQ221 - PQ237 1PQ241 - PQ243 1PQ251 - PQ267 1PQ281 - PQ296 2PQ297 - PQ299 1PQ301 - PQ307 1PQ331 - PQ332 1PQ341 - PQ344 2PQ345 - PQ348 1PQ361 - PQ369 2PQ370 - PQ373 2PQ391 - PQ395 1PQ401 - PQ408 2PQ409 - PQ410 1PQ411 - PQ413 2PQ414 - PQ418 1PQ421 2PQ431 - PQ438 2PQ447 - PQ448 Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: June 17, 1999 737-53A1214Revision 5: January 30, 2015 17 of 77 BOEING SERVICE BULLETIN 737-53A1214 ALERTALERT ### Page 18 GroupVariable Number 2PQ451 2PQ454 1PQ471 - PQ473 2PQ474 - PQ475 1PQ479 - PQ481 1PQ486 - PQ487 1PQ491 - PQ493 1PQ771 2PQ772 1PQ791 - PQ793 1PQ801 - PQ805 1PQ931 - PQ932 2PQ933 - PQ935 2PQ951 2PQ971 - PQ997 2PR001 - PR017 2PR021 - PR034 2PR041 - PR045 2PR061 - PR072 2PR077 - PR082 2PR091 - PR092 2PR096 2PR101 2PR121 - PR122 2PR131 - PR132 2PR141 - PR143 2PR161 - PR172 2PR181 1PS601 - PS616 2PS617 - PS630 1PS631 1PS636 - PS638 1PS641 - PS644 Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: June 17, 1999 737-53A1214Revision 5: January 30, 2015 18 of 77 BOEING SERVICE BULLETIN 737-53A1214 ALERTALERT ### Page 19 GroupVariable Number 1PS651 - PS657 1PS666 - PS669 1PS691 - PS692 1PS701 - PS703 2PS704 - PS706 1PS751 - PS762 2PS763 - PS799 2PS811 2PS836 - PS837 2PS841 - PS846 2PS851 - PS852 2PS856 2PS861 - PS863 2PS866 - PS868 2PS871 - PS874 2PS896 - PS897 2PS901 - PS941 2PS956 - PS957 2PS961 - PS963 2PS971 - PS978 1PT001 - PT011 2PT012 - PT015 1PT021 - PT028 2PT029 - PT031 1PT041 - PT064 1PT101 - PT105 1PT121 - PT125 2PT126 - PT138 1PT146 - PT148 1PT161 - PT170 1PT181 - PT187 2PT188 1PT211 - PT220 Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: June 17, 1999 737-53A1214Revision 5: January 30, 2015 19 of 77 BOEING SERVICE BULLETIN 737-53A1214 ALERTALERT ### Page 20 GroupVariable Number 1PT295 1PT301 - PT306 2PT307 - PT309 1PT331 - PT360 1PT381 - PT399 1PT401 - PT438 1PT501 - PT512 2PT513 - PT517 1PT561 - PT565 1PT581 - PT584 2PT585 - PT586 1PT611 - PT621 1PT641 - PT642 2PT643 - PT644 1PT651 - PT655 2PT656 1PT671 - PT672 2PT681 - PT685 1PT701 - PT703 2PT716 - PT717 2PT721 - PT725 2PT801 - PT834 2PT851 - PT854 2PT871 - PT886 2PT901 - PT930 2PT971 - PT973 2PT981 - PT985 2PT996 1PU001 - PU025 2PU301 2PU311 - PU313 1PV001 - PV055 1PV201 - PV203 Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: June 17, 1999 737-53A1214Revision 5: January 30, 2015 20 of 77 BOEING SERVICE BULLETIN 737-53A1214 ALERTALERT ### Page 21 GroupVariable Number 2PV204 - PV209 2PV226 - PV229 1PV231 - PV237 1PV271 - PV272 1PV281 - PV283 2PV284 - PV287 2PV296 2PV301 - PV302 2PV351 2PV356 - PV357 1PW001 - PW054 1PW061 - PW068 1PW072 2PW086 - PW088 1PW091 - PW094 1PW101 - PW102 1PW106 1PW111 - PW120 1PW156 - PW157 1PW161 - PW167 2PW168 - PW171 1PW201 - PW245 2PW246 - PW252 1PW261 2PW262 - PW264 1PW265 - PW268 2PW271 - PW276 1PW278 1PW281 - PW284 2PW285 - PW292 1PW293 1PW296 1PW301 - PW327 Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: June 17, 1999 737-53A1214Revision 5: January 30, 2015 21 of 77 BOEING SERVICE BULLETIN 737-53A1214 ALERTALERT ### Page 22 GroupVariable Number 2PW401 - PW408 2PW411 - PW418 2PW421 - PW424 2PW431 - PW435 2PW441 - PW450 1PW461 - PW467 1PW501 - PW504 1PW511 - PW520 2PW521 - PW522 2PW524 - PW525 1PW526 2PW527 - PW530 1PW531 - PW546 2PW547 - PW550 1PW556 - PW557 1PW561 - PW564 1PW571 - PW576 1PW591 - PW596 1PW611 - PW620 2PW621 - PW622 1PW631 - PW634 2PW635 - PW637 1PW661 - PW662 1PW681 - PW683 1PW701 - PW702 1PW711 - PW717 1PW741 - PW742 1PW761 1PW771 2PW831 2PW851 - PW856 1PX071 1PX701 Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: June 17, 1999 737-53A1214Revision 5: January 30, 2015 22 of 77 BOEING SERVICE BULLETIN 737-53A1214 ALERTALERT ### Page 23 GroupVariable Number 1PY001 - PY008 1PY021 - PY022 1PY031 1PY036 - PY037 1PY046 - PY048 1PY051 - PY053 1PY056 - PY057 1PY101 - PY103 1PY111 - PY113 1PY131 - PY135 1PY141 - PY143 1PY151 - PY154 1PY156 - PY157 1PY161 - PY162 1PY166 1PY191 1PY201 1PY221 - PY222 1PY231 1PY241 - PY244 1PY270 - PY275 1PY281 1PY286 1PY301 - PY304 1PY321 - PY323 1PY341 - PY346 1PY361 - PY362 1PY381 1PY401 1PY409 - PY411 1PY421 - PY422 1PY441 1PY451 Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: June 17, 1999 737-53A1214Revision 5: January 30, 2015 23 of 77 BOEING SERVICE BULLETIN 737-53A1214 ALERTALERT ### Page 24 GroupVariable Number 1PY461 - PY463 1PY591 - PY595 1PY611 - PY612 1PY621 1PY631 1PY651 1PY671 - PY672 1PY721 1PY741 2. Spares Affected None. B. Concurrent Requirements None. C. Reason Cracks have been reported in four general areas on the aft pressure bulkhead: cracks in the web at the web-to-"Y" chord interface; cracks in the web at the outer circumferential tear strap; cracks in the web near the dome cap; and cracks in the "Z" stiffeners near the dome cap. Undetected cracking could result in loss of ability to maintain cabin pressure, rapid decompression of the airplane, and significant structural damage to the aft fuselage. As of the initial release of this service bulletin, six operators had reported finding cracks in the aft pressure bulkhead web of sixteen 737-200 and -300 airplanes. In all of the cases, the cracks ran in the circumferential direction along the aft row of fasteners connecting the web assembly to the bulkhead "Y" chord. Fifteen airplanes had cracks at Stringer (S)-6L and one airplane had cracks at S-6L and S-6R. The airplanes had accumulated between 25,500 and 68,000 flight cycles and between 45,500 and 61,000 flight hours. Since the initial release of this bulletin, there have been additional reports of cracking. The cracks were similar to the previously reported cracks. Cracks have been reported on airplanes with a range of between 22,966 and 67,937 flight cycles. Also, there have been two reports of cracking in the bulkhead web at the outer circumferential tear strap. The first report happened in 1978 and resulted in the release of a Structural Item Interim Advisory (SIIA) SIIA 737-52. In that event, the airplane experienced a sudden cabin pressure drop as a result of a 42 inch crack in the bulkhead web. The crack ran along the outer circumferential tear strap from S-15R to S-21, turned 90 degrees inwards and ran along the radial stiffener at S-21R, stopping at the middle circumferential tear strap. The second report happened in January of 1999 and resulted in the release of SIIA 737-269. The operator discovered an eight inch crack during a heavy maintenance check. The crack ran along the outer circumferential tear strap from S-15R to S-18R. The airplanes had 21,246 and 26,162 flight cycles and 17,500 and 24,132 flight hours respectively. Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: June 17, 1999 737-53A1214Revision 5: January 30, 2015 24 of 77 BOEING SERVICE BULLETIN 737-53A1214 ALERTALERT ### Page 25 Since revision 2 of this bulletin, there have been reports of cracking in the web near the dome cap. The cracks occurred at the center of the bulkhead at the edge of web gore sections. The airplanes had accumulated more than 30,000 flight cycles and 36,000 flight hours. There have also been reports of cracking in the radial "Z" stiffeners where they attach to the dome cap. The cracks extended from the outboard fastener hole and ran circumferentially. Revision 1 was sent to: — Modify Industry Support Information. — add an SRM repair reference for repairing cracking in the web periphery at S-6L or S-6R. — add a visual inspection for oil-canning for the entire bulkhead web. — add an NDT inspection for cracking in the web at the outer circumferential tear strap around the entire bulkhead. — add an inspection for cracking in the web at the "Y" chord below S-15L and S-15R. Revision 2 was sent to: — Clarify the inspection threshold in the compliance section. — Change two SRM figure references and add a note. The note states that more work is required if an operator used the wrong SRM figure to do a web crack repair. Revision 3 was sent to: — Add an inspection for cracking in the web joints in the center of the aft pressure bulkhead. — Add inspections for cracking in the radial "Z" stiffeners where they attach to the dome cap. — Add repeat inspections for oil cans. — Add Appendices A to D to show post repair inspections for repairs that have been deleted from the SRM. — Add Appendix E to show the removal and replacement of a repair that has been deleted from the SRM. — Add SRM references for new oil can repairs and repairs for web cracking at the center of the bulkhead. — Change the Industry Support Information statement. — Clarify the inspection in Figure 1, step 2. Revision 4 was sent to change the compliance time for Detailed Inspection for Oil-Cans and to delete incorrect paragraph reference in Paragraph 3.B., Work Instructions, Part VI. Revision 5 is sent to incorporate a Widespread Fatigue Damage (WFD) analysis for Group 2 airplanes. Beginning at 76,000 total flight cycles, the repeat inspection interval is decreased for Non-Destructive Testing (NDT) inspections of the web at the "Y" Chord. The data given in Alternative Method of Compliance Notice (AMOC) SB 737-53A1214-AMOC-01 is included in Revision 5 of this service bulletin. The data given in Alternative Method of Compliance Notice (AMOC) SB 737-53A1214-AMOC-02 is included in Revision 5 of this service bulletin. The data given in Global Alternative Method of Compliance Notice (GAMOC) 120S-12-630 is included in Revision 5 of this service bulletin. Boeing Service Related Problem (SRP) 737-SRP-53-0109, 737-SRP-53-0116, 737-SRP-53-0155, and 737-SRP-53-0417 are related to this service bulletin. Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: June 17, 1999 737-53A1214Revision 5: January 30, 2015 25 of 77 BOEING SERVICE BULLETIN 737-53A1214 ALERTALERT ### Page 26 D. Description Inspect the web for cracking at the "Y" chord in the upper bulkhead from S-15L to S-15R: — Get access to the aft side of the aft pressure bulkhead and do a Low Frequency Eddy Current (LFEC) inspection for any cracking in the web periphery. Do the inspection for circumferential cracking in the web where it attaches to the "Y" chord along the aft row of fasteners. Do the inspection in the upper fuselage from S-15L to S-15R. Also do a Detailed Inspection for any cracking in the web and for any incorrectly drilled or elongated fastener hole(s). — If either cracking, incorrectly drilled fastener hole or elongated fastener hole is found, you must get access to the forward side of the bulkhead and do a High Frequency Eddy Current (HFEC) inspection for any cracking and a Detailed Inspection from the forward side. Do the HFEC inspections for circumferential cracking along the aft row of fasteners at the "Y" chord for the section of web where the cracking, incorrectly drilled fastener hole or elongated fastener hole was found. It is not necessary to do the HFEC inspection beyond the web splices of the web section containing the cracking, incorrectly drilled fastener hole or elongated fastener hole. Do the Detailed Inspection for any cracking in the web and for any incorrectly drilled or elongated fastener hole(s). If you find damage at S-6L or S-6R, repair it as shown in the 737-100/200 or 737-300/400/500 SRM as applicable. If you install the SRM repair, there are future inspection requirements as defined in the SRM repair. If you find any cracking in the web periphery that is not covered by the SRM, contact Boeing for repair instructions and do the repair. — As an option to doing the inspections on the aft side of the bulkhead, you can do the HFEC and Detailed Inspection from the forward side of the bulkhead directly at less frequent intervals. — Do repeat inspections at the times shown in Paragraph 1.E., Compliance. Once the SRM repair is accomplished, subsequent inspections become less frequent. Inspect the web for cracking at the "Y" chord in the lower bulkhead from S-15L to S-15R: — This inspection is identical to the inspection above stringers S-15L and S-15R (upper lobe) and is done using a LFEC, HFEC, and Detailed Inspection procedures from the forward and the aft side. The compliance time for this inspection is different than the compliance time for the upper-lobe inspection. Refer to Paragraph 1.E., Compliance for compliance information. — Do repeat inspections at the times shown in Paragraph 1.E., Compliance. — If you find any cracking in this area, contact Boeing for repair instructions and do the repair. Inspect the web for any cracking at the outer circumferential tear strap: — From the aft side of the bulkhead, do a LFEC inspection for any cracking in the web at the outer circumferential tear strap around the entire bulkhead. As an option, you can do a HFEC inspection from the forward side of the bulkhead. Refer to Paragraph 1.E., Compliance for compliance information. — If you find any cracking in this area, repair in accordance with the SRM or contact Boeing for repair instructions and do the repair. Inspect the web for oil-cans: — From the aft side of the bulkhead, do a Detailed Inspection for oil-cans. — If you find oil-cans beyond SRM allowable limits, repair it as shown in the SRM. — If you find an oil-can within SRM allowable limits, repair as shown in the SRM, OR if the oil can is within the SRM allowable limits you can monitor the condition with repeat inspections and repair as shown in the SRM within the time shown in Paragraph 1.E., Compliance. — Do repeat inspections at the times shown in Paragraph 1.E., Compliance. Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: June 17, 1999 737-53A1214Revision 5: January 30, 2015 26 of 77 BOEING SERVICE BULLETIN 737-53A1214 ALERTALERT ### Page 27 Inspect the web for any cracking at the dome cap at the center of the bulkhead: — From the aft side of the bulkhead, do a NDT inspection for any cracking in the bulkhead web near the dome cap. — If you find any cracking in this area, repair as shown in the SRM. — Do repeat inspections at the times shown in Paragraph 1.E., Compliance. Inspect the forward flange of the "Z" stiffeners for any cracking at the dome cap at the center of the bulkhead: — From the fwd side of the bulkhead, do a NDT inspection for any cracking in the forward flange of the "Z" stiffeners at the dome cap. Do the inspection at both fastener rows common to the dome. — If you find any cracking in this area, contact Boeing for repair instructions and do the repair. — Do repeat inspections at the times shown in Paragraph 1.E., Compliance. Revision 5: Group 1: No more work is necessary on the airplane(s) changed or inspected in accordance with Revision 4 of this service bulletin. These airplanes will reach their limit of validity prior to the compliance time for the inspections added by this service bulletin revision. Group 2: More work is necessary on the airplane(s) changed or inspected in accordance with Revision 4 of this service bulletin. Beginning at 76,000 total flight cycles, the repeat inspection interval is reduced for Non-Destructive Testing (NDT) inspections of the web at the "Y" Chord. The work in this service bulletin is done in the maintenance zone(s) given below. Group 1: Affected Maintenance Zones ZoneModel 7-1, 2-20737-100, 737-200, 737-200C Group 1-2: Affected Maintenance Zones ZoneModel 220, 701737-300, 737-400, 737-500 E. Compliance Federal Aviation Administration (FAA) Airworthiness Directive AD 2012-18-13 R1 is related to this service bulletin. The effective date of AD 2012-18-13 R1 is June 13, 2013. The Federal Aviation Administration (FAA) will possibly release an additional Airworthiness Directive related to this service bulletin. This airworthiness directive would make certain compliance tasks and times given in Revision 5 of this service bulletin mandatory for Group 2 airplanes. Do the required actions in accordance with Paragraph 3. Accomplishment Instructions. Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: June 17, 1999 737-53A1214Revision 5: January 30, 2015 27 of 77 BOEING SERVICE BULLETIN 737-53A1214 ALERTALERT ### Page 28 NOTE: Boeing endorses the new FAA rules related to Limit of Validity (LOV) and recommends immediate and permanent removal from service of any airplane upon reaching the LOV, whether or not it is operated under FAA jurisdiction. As such, Boeing no longer provides maintenance instructions for airplanes that have accumulated flight cycles beyond the LOV. Line numbers 1-291 have accumulated flight cycles beyond the LOV of the airplane. 14 Code of Federal Regulations (CFR) Part 121.1115 and 129.115 prohibit operation of an airplane beyond its LOV. Group 1: TABLE 1: INSPECTION REQUIREMENTS - NDT INSPECTION OF WEB AT "Y" CHORD IN THE UPPER BULKHEAD FROM S-15L TO S-15R Repeat Interval Flight Cycles (Not to Exceed) (a) Compliance Time (whichever occurs lat- er) (a) ActionCondition Above S-15L to S- 15R except S-5L to S-7L and S-5R to S-9R S-5L to S-7L and S-5R to S- 9R Upper Fuselage from S- 15L to S-15R 6,000 flight cycles from last LFEC In- spection, 1,200 flight cy- cles from last LFEC Inspec- tion, Within 375 flight cycles after the effective date of AD 99-08-23, OR Eddy Current Inspection and Detailed Inspection for any cracking or any in- correctly drilled or elongat- ed fastener hole(s) in ac- cordance with Paragraph 3.B., Work Instructions, PART I. 25,000 Total Flight Cycles or more OR 12,000 flight cycles from last HFEC In- spection. OR 3,800 flight cy- cles from the last HFEC Inspec- tion. Within 1,200 flight cycles or within 12 months after the last inspection accom- plished in accordance with Paragraph (a)(2) of AD 99-08-23, whichever occurs first. OR Within 1,200 flight cycles after the last LFEC (aft side) inspection, OR Within 3,800 flight cycles after the last HFEC (fwd side) inspection. --Before further flight.HFEC Inspection and De- tailed Inspection from the forward side for any cracking and any incorrect- ly drilled or elongated fas- tener hole(s). (b) Any cracking or incorrectly drilled fastener hole or elongated fasten- er hole is found ---Repeat inspections at specified intervals No cracking or in- correctly drilled or elongated fasten- er hole(s) found Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: June 17, 1999 737-53A1214Revision 5: January 30, 2015 28 of 77 BOEING SERVICE BULLETIN 737-53A1214 ALERTALERT ### Page 29 Group 1: TABLE 1: INSPECTION REQUIREMENTS - NDT INSPECTION OF WEB AT "Y" CHORD IN THE UPPER BULKHEAD FROM S-15L TO S-15R Repeat Interval Flight Cycles (Not to Exceed) (a) Compliance Time (whichever occurs lat- er) (a) ActionCondition Above S-15L to S- 15R except S-5L to S-7L and S-5R to S-9R S-5L to S-7L and S-5R to S- 9R Upper Fuselage from S- 15L to S-15R --Before further flight.Repair in accordance with the Structural Repair Manual Any cracking or any incorrectly drilled or elongat- ed fastener hole(s) found at S-5L to S-7L or at S-5R to S-9R --Before further flight.Contact Boeing for repair instructions and do the re- pair. Any cracking or any incorrectly drilled or elongat- ed fastener hole(s) found at S-15L to S-7L, S- 15R to S-9R or above S-5L to S- 5R (a) If you install the SRM repair doubler at S-6L or S-6R in accordance with 737-100/200 SRM 53-10-4 or 737-300 SRM 53-80-08, Repair 7 or 737-400 SRM 53-80-08, Repair 7 or 737-500 SRM 53-80-08, Repair 7, refer to the SRM for Inspection threshold and repeat Inspection intervals for the area of the web covered by the repair doubler. (b) Do the HFEC Inspection for any cracking in the section of web where the cracking or incorrectly drilled or elongated fastener hole was found. It is not necessary to do the HFEC Inspection beyond the web splices of the web section containing the cracking, incorrectly drilled fastener hole or elongated fastener hole. Group 1: Table 2: Inspection Requirements - NDT Inspection of Web at "Y" Chord in the Lower Bulkhead from S- 15L to S-15R Repeat Interval Flight Cycles (Not to Exceed) Compliance TimeActionCondition 6,000 flight cycles from the last LFEC Inspection (aft side). (a) Before 30,000 total flight cycles. Eddy Current Inspection and De- tailed Inspection for any cracking and for any incorrectly drilled or elongated fastener hole(s) or corro- sion in accordance with Paragraph 3.B., Work Instructions, PART III. Less than 24,000 Total Flight Cycles OR 12,000 flight cycles from the last HFEC Inspection (forward side). (a) Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: June 17, 1999 737-53A1214Revision 5: January 30, 2015 29 of 77 BOEING SERVICE BULLETIN 737-53A1214 ALERTALERT ### Page 30 Group 1: Table 2: Inspection Requirements - NDT Inspection of Web at "Y" Chord in the Lower Bulkhead from S- 15L to S-15R Repeat Interval Flight Cycles (Not to Exceed) Compliance TimeActionCondition 6,000 flight cycles from the last LFEC Inspection (aft side). (a) Within 6,000 flight cy- cles or two years, whichever comes first, after the Revision 3 date of this service bul- letin. Eddy Current Inspection and De- tailed Inspection for any cracking and for any incorrectly drilled or elongated fastener hole(s) or corro- sion in accordance with Paragraph 3.B., Work Instructions, PART III. 24,000 Total Flight Cycles or more OR 12,000 flight cycles from the last HFEC Inspection (forward side). (a) -Before further flightContact Boeing for repair instructions and do the repair. Any cracking, any incorrectly drilled or elongated fastener hole(s) or corrosion found (a) In many areas the access is limited and you can do an inspection from only one side: either the forward side (HFEC) or the aft side (LFEC). In these areas, do the inspection from the side which provides access. Table 3: Inspection Requirements - NDT Inspection under Tear Strap Repeat Interval Flight Cycles (Not to Exceed) Compliance TimeActionCondition One-time inspec- tion only. Before 16,200 total flight cy- cles. Eddy Current Inspection for any cracking in accordance with Paragraph 3.B., Work Instructions, PART II, Step 1. Less than 15,000 Total Flight Cycles One-time inspec- tion only. Within 1,200 flight cycles or six months, whichever comes first, after the Revi- sion 1 date of this service bulletin. Eddy Current Inspection for any cracking in accordance with Paragraph 3.B., Work Instructions, PART II, Step 1. 15,000 Total Flight Cycles or more -Before further flightContact Boeing for repair instructions and do the repair. Any cracking found Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: June 17, 1999 737-53A1214Revision 5: January 30, 2015 30 of 77 BOEING SERVICE BULLETIN 737-53A1214 ALERTALERT ### Page 31 Table 4: Inspection Requirements - Detailed Inspection for Oil-Cans Repeat Interval Flight Cycles (Not to Exceed) Compliance TimeActionOptionCondition -Before 15,000 total flight cycles. Detailed Inspection for Oil- Cans in accordance with Paragraph 3.B., Work Instruc- tions, PART II, Step 2. -Initial Inspection for Oil-Cans OR Within 1,200 flight cycles after the Revision 1 date of this service bulletin, whichever comes later. -Before further flight.Contact Boeing for repair in- structions and do the repair. -Any cracking is found. 6,000Within 6,000 flight cycles from prior inspection. Detailed Inspection for Oil- Cans in accordance with Paragraph 3.B., Work Instruc- tions, PART II, Step 2. -No Oil-Cans on Initial Inspection or Repeat In- spections. OR Within 1,200 flight cycles after the Revision 3 date of this service bulletin, whichever comes later. -Before further flight.Contact Boeing for repair in- structions and do the repair. -Any cracking is found. 1,200 (a)Before further flight.Detailed and NDT Inspection in accordance with Paragraph 3.B., Work Instructions, PART II, Step 2. Option 1 (de- fer repair) Oil-Cans found within limits de- fined in SRM. -Within 12,000 flight cycles from the time when the oil can is found. Install the repair in accor- dance with Paragraph 3.B., Work Instructions, PART II, Step 2. -Before further flight.Install the repair in accor- dance with Paragraph 3.B., Work Instructions, PART II, Step 2. Option 2 (re- pair immedi- ately) -Before further flight.Contact Boeing for repair in- structions and do the repair. -Any cracking is found. -Before further flight.Install the repair in accor- dance with Paragraph 3.B., Work Instructions, PART II, Step 2. -Oil-Cans found outside of allow- able limits de- fined in SRM. (a) Repeat inspections are terminated when the repair is installed. Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: June 17, 1999 737-53A1214Revision 5: January 30, 2015 31 of 77 BOEING SERVICE BULLETIN 737-53A1214 ALERTALERT ### Page 32 Table 5: Inspection Requirements - NDT Inspection of the Dome Cap at the Center of the Bulkhead Repeat Interval Flight Cycles (Not to Exceed) Compliance TimeActionCondition 6,000Before 30,000 total flight cycles. Eddy Current Inspection of the Dome Cap for any cracking in accordance with Para- graph 3.B., Work Instructions, PART IV. Less than 24,000 Total Flight Cycles 6,000Within 6,000 flight cycles or 2 years, whichever comes first, after the Revi- sion 3 date of this service bulletin. Eddy Current Inspection of the Dome Cap for any cracking in accordance with Para- graph 3.B., Work Instructions, PART IV. 24,000 Total Flight Cycles or more -Before further flight.Install the repair in accordance with Para- graph 3.B., Work Instructions, PART IV. Any cracking found Table 6: Inspection Requirements - NDT Inspection of the Forward Flange of the "Z" Stiffeners at the Dome Cap Repeat Interval Flight Cycles (Not to Exceed) Compliance TimeActionCondition 12,000Before 30,000 total flight cycles. HFEC Inspection of the forward flanges of the "Z" stiffener for any cracking in accor- dance with Paragraph 3.B., Work Instruc- tions, PART V. Less than 24,000 Total Flight Cycles 12,000Within 6,000 flight cycles or 2 years, whichever comes first, after the Revi- sion 3 date of this service bulletin. HFEC Inspection of the forward flanges of the "Z" stiffener for any cracking in accor- dance with Paragraph 3.B., Work Instruc- tions, PART V. 24,000 Total Flight Cycles or more -Before further flight.Contact Boeing for repair instructions and do the repair. Any cracking found Table 7: Inspection Requirements - Inspection for Existing Repairs Compliance TimeActionCondition Within 4,500 flight cycles after the Revi- sion 3 date of this service bulletin. Do a detailed inspection of the bulkhead web and stiffeners to find existing repairs on the bulkhead in accordance with Paragraph 3.B., Work Instructions, Part VI. All Airplanes At the applicable time in accordance with Table 8. Do Eddy Current Inspections or repair replace- ment as necessary, in accordance with Para- graph 3.B., Work Instructions, PART II. Obsolete SRM re- pair installed. Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: June 17, 1999 737-53A1214Revision 5: January 30, 2015 32 of 77 BOEING SERVICE BULLETIN 737-53A1214 ALERTALERT ### Page 33 Table 7: Inspection Requirements - Inspection for Existing Repairs Compliance TimeActionCondition At the applicable time in accordance with the SRM. Do Eddy Current Inspections in accordance with Paragraph 3.B., Work Instructions, PART II. Current SRM repair installed. At the time in accordance with the FAA approved Damage Tolerance Inspec- tions. Do the FAA approved Damage Tolerance Inspec- tions. Non SRM repair in- stalled and the re- pair has FAA ap- proved Damage Tolerance Inspec- tions. Within 4,500 flight cycles after the Revi- sion 3 date of this service bulletin. Contact Boeing for FAA approved Damage Tol- erance Inspections. Non SRM repair in- stalled and the re- pair does not have FAA approved Damage Tolerance Inspections. At the time in accordance with the FAA approved Damage Tolerance Inspec- tions. Do the FAA approved Damage Tolerance Inspec- tions. Table 8: Requirements for Obsolete SRM Repairs Repeat Interval Flight Cycles (Not to Exceed) Compliance Time (Whichever Occurs Later) ActionConditionReference 12,000 for HFEC inspection. 6,000 for LFEC Inspec- tion. Within 12,000 flight cycles after the repair was installed, OR Do a HFEC inspection of the web at fastener locations not common to a tear strap in accordance with APPENDIX A 737-300 SRM 53-80-08, Repair 1 or 737-400 SRM 53-80-08, Repair 1 or 737-500 SRM 53- 80-08, Repair 1 in- stalled (obsolete - older SRM) or 737-100/200 SRM 53-10-4, Figure 3 repair installed (obso- lete - older SRM) APPENDIX A - Repair For Damage to Web and Strap Within 6,000 Flight Cycles after the Revi- sion 3 date of this service bulletin. OR At the operators option, do a LFEC inspection of the web in accordance with AP- PENDIX A 12,000 for HFEC Inspection. 6,000 for LFEC Inspec- tion. Within 12,000 flight cycles after the repair was installed, OR Do a HFEC inspection of the web at fastener locations common to a tear strap in accordance with APPENDIX A Within 6,000 Flight Cycles after the Revi- sion 3 date of this service bulletin. OR At the operators option, do a LFEC inspection of the web in accordance with AP- PENDIX A Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: June 17, 1999 737-53A1214Revision 5: January 30, 2015 33 of 77 BOEING SERVICE BULLETIN 737-53A1214 ALERTALERT ### Page 34 Table 8: Requirements for Obsolete SRM Repairs Repeat Interval Flight Cycles (Not to Exceed) Compliance Time (Whichever Occurs Later) ActionConditionReference 12,000 for HFEC Inspection. 6,000 for LFEC Inspec- tion. Within 12,000 flight cycles after the repair was installed, OR Do a HFEC inspection of the web and repair plate in accor- dance with APPENDIX B OR 737-300 SRM 53-80-08, Repair 1 or 737-400 SRM 53-80-08, Repair 1 or 737-500 SRM 53- 80-08, Repair 1 in- stalled (obsolete - older SRM) or 737-100/200 SRM 53-10-4, Figure 3 repair installed (obso- lete - older SRM) APPENDIX B - Repair For Damage to Web Within 6,000 flight cycles after the Revi- sion 3 date of this service bulletin. At the operators option, do a LFEC inspection of the web in accordance with AP- PENDIX B 12,000 for HFEC Inspection. 6,000 for LFEC Inspec- tion. Within 12,000 flight cycles after the repair was installed, OR Do a HFEC inspection of the web in accordance with AP- PENDIX C OR 737-300 SRM 53-80-08, Repair 2 or 737-400 SRM 53-80-08, Repair 2 or 737-500 SRM 53- 80-08, Repair 2 in- stalled (obsolete - older SRM) or 737-100/200 SRM 53-10-4, Figure 5 repair installed (obso- lete - older SRM) APPENDIX C - Repair For Oil Can in Web. Within 6,000 flight cycles after the Revi- sion 3 date of this Service Bulletin. At the operators option, do a LFEC inspection of the web in accordance with AP- PENDIX C 6,000Within 12,000 flight cycles after the repair was installed, Do a LFEC inspection of the web in accordance with AP- PENDIX D 737-300 SRM 53-80-08, Repair 4 or 737-400 SRM 53-80-08, Repair 4 or 737-500 SRM 53- 80-08, Repair 4 in- stalled (obsolete - older SRM) or 737-100/200 SRM 53-10-4, Figure 12 repair installed (obso- lete - older SRM) APPENDIX D - Repair For Oil Can in Web (Not at Strap) OR Within 6,000 Flight Cycles after the Revi- sion 3 date of this Service Bulletin. 12,000Within 12,000 Flight Cycles after the re- pair was installed, Do a HFEC inspection of the web in accordance with AP- PENDIX D OR Within 6,000 flight cycles after the Revi- sion 3 date of this service bulletin. Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: June 17, 1999 737-53A1214Revision 5: January 30, 2015 34 of 77 BOEING SERVICE BULLETIN 737-53A1214 ALERTALERT ### Page 35 Table 8: Requirements for Obsolete SRM Repairs Repeat Interval Flight Cycles (Not to Exceed) Compliance Time (Whichever Occurs Later) ActionConditionReference -Within 6,000 flight cycles after the Revi- sion 3 date of this service bulletin. Remove the existing repair and replace in accordance with 737-100/200 SRM 53- 10-4, Figure 3A repair in- stalled (obsolete - older SRM) 737-300 SRM 53-80- 08, Repair 11 or 737-400 SRM 53-80-08, Repair 11 or 737-500 SRM 53-80-08, Re- pair 11 as applicable. 737-300 SRM 53-80-08, Repair 5 or 737-400 SRM 53-80-08, Repair 5 or 737-500 SRM 53- 80-08, Repair 5 in- stalled (obsolete - older SRM) or 737-100/200 SRM 53-10-4, Figure 13 repair installed (obso- lete - older SRM) APPENDIX E - Repair For Oil Can in Web and Strap. Group 2: TABLE 9: INSPECTION REQUIREMENTS - NDT INSPECTION OF WEB AT "Y" CHORD IN THE UPPER BULKHEAD FROM S-5L TO S-7L and S-5R TO S-9R Repeat Interval Flight Cycles (Not to Exceed) (a) Compliance Time (Whichever Occurs Later) (a) ActionCondition 1,200 flight cycles from last LFEC In- spection, Within 375 flight cycles after the effective date of AD 99- 08-23, Eddy Current Inspection and Detailed Inspection for any cracking or any in- correctly drilled or elongated fastener hole(s) in accordance with Paragraph 3.B., Work Instructions, PART I. 25,000 Total Flight Cycles or more OR 3,800 flight cycles from the last HFEC Inspection. OR Within 1,200 flight cycles or within 12 months after the last inspection accomplished in accordance with AD 99- 08-23, whichever occurs first, OR Within 1,200 flight cycles af- ter the last LFEC (aft side) inspection, OR Within 3,800 flight cycles af- ter the last HFEC (fwd side) inspection. -Before further flight.HFEC Inspection and Detailed Inspec- tion from the forward side for any cracking or any incorrectly drilled or elongated fastener hole(s). (b) Any cracking or incor- rectly drilled fastener hole or elongated fastener hole is found Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: June 17, 1999 737-53A1214Revision 5: January 30, 2015 35 of 77 BOEING SERVICE BULLETIN 737-53A1214 ALERTALERT ### Page 36 Group 2: TABLE 9: INSPECTION REQUIREMENTS - NDT INSPECTION OF WEB AT "Y" CHORD IN THE UPPER BULKHEAD FROM S-5L TO S-7L and S-5R TO S-9R Repeat Interval Flight Cycles (Not to Exceed) (a) Compliance Time (Whichever Occurs Later) (a) ActionCondition --Repeat inspections at specified inter- vals No cracking or no in- correctly drilled or no elongated fastener hole(s) found -Before further flight.Repair in accordance with the Struc- tural Repair Manual Any cracking or any incorrectly drilled or elongated fastener hole(s) found at S- 5L to S-7L or at S- 5R to S-9R (a) If you install the SRM repair doubler at S-6L or S-6R in accordance with 737-300 SRM 53-80-08, Repair 7 or 737-400 SRM 53-80-08, Repair 7 or 737-500 SRM 53-80-08, Repair 7, refer to the SRM for Inspection threshold and repeat Inspection intervals for the area of the web covered by the repair doubler. (b) Do the HFEC Inspection for any cracking in the section of web where the cracking or incorrectly drilled or elongated fastener hole was found. It is not necessary to do the HFEC Inspection beyond the web splices of the web section containing the cracking, incorrectly drilled fastener hole or elongated fastener hole. Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: June 17, 1999 737-53A1214Revision 5: January 30, 2015 36 of 77 BOEING SERVICE BULLETIN 737-53A1214 ALERTALERT ### Page 37 Group 2: TABLE 10: INSPECTION REQUIREMENTS - NDT INSPECTION OF WEB AT "Y" CHORD IN THE UPPER BULKHEAD ABOVE S-15L TO S-15R EXCEPT S-5L TO S-7L AND S-5R TO S-9R Repeat Interval Flight Cycles (Not to Exceed) Compliance Time (whichever occurs lat- er) ActionCondition 6,000 flight cycles from last LFEC In- spection, Airplanes with less than 76,000 total flight cycles Within 375 flight cycles after the effective date of AD 99-08-23, Eddy Current Inspection and Detailed Inspection for any cracking or any in- correctly drilled or elongat- ed fastener hole(s) in ac- cordance with Paragraph 3.B., Work Instructions, PART I. 25,000 Total Flight Cycles or more OR 12,000 flight cycles from last HFEC In- spection. OR Within 1,200 flight cycles or within 12 months after the last inspection accom- plished in accordance with AD 99-08-23, whichever occurs first. 4,500 flight cycles from last LFEC In- spection, Airplanes with 76,000 total flight cycles or moreOR ORWithin 1,200 flight cycles after the last LFEC (aft side) inspection, 9,500 flight cycles from last HFEC In- spection.OR Within 3,800 flight cycles after the last HFEC (fwd side) inspection. --Before further flight.HFEC Inspection and De- tailed Inspection from the forward side for any cracking or any incorrectly drilled or elongated fasten- er hole(s). (a) Any cracking or incorrectly drilled fastener hole or elongated fasten- er hole is found ---Repeat inspections at specified intervals No cracking or no incorrectly drilled or no elongated fastener hole(s) found --Before further flight.Contact Boeing for repair instructions and do the re- pair. Any cracking or any incorrectly drilled or elongat- ed fastener hole(s) found at S-15L to S-7L, S- 15R to S-9R or above S-5L to S- 5R (a) Do the HFEC Inspection for any cracking in the section of web where the cracking or incorrectly drilled or elongated fastener hole was found. It is not necessary to do the HFEC Inspection beyond the web splices of the web section containing the cracking, incorrectly drilled fastener hole or elongated fastener hole. Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: June 17, 1999 737-53A1214Revision 5: January 30, 2015 37 of 77 BOEING SERVICE BULLETIN 737-53A1214 ALERTALERT ### Page 38 Group 2: TABLE 11: INSPECTION REQUIREMENTS - NDT INSPECTION OF WEB AT "Y" CHORD IN THE LOWER BULKHEAD FROM S-15L TO S-15R Repeat Interval Flight Cycles (Not to Exceed) Compliance TimeActionCondition 6,000 flight cycles from last LFEC In- spection (aft side) (a), Before 30,000 Total Flight Cycles Eddy Current Inspection and Detailed Inspection for any cracking or any in- correctly drilled or elongat- ed fastener hole(s) in ac- cordance with Paragraph 3.B., Work Instructions, PART III. Less than 24,000 Total Flight Cy- cles OR 12,000 flight cycles from last HFEC Inspection (forward side). (a) 6,000 flight cycles from last LFEC In- spection, Airplanes with less than 76,000 total flight cycles Within 6,000 flight cycles or two years, whichever comes first, after the Re- vision 3 date of this ser- vice bulletin Eddy Current Inspection and Detailed Inspection for any cracking or any in- correctly drilled or elongat- ed fastener hole(s) in ac- cordance with Paragraph 3.B., Work Instructions, PART III. 24,000 Total Flight Cycles or more OR 12,000 flight cycles from last HFEC In- spection. 4,500 flight cycles from last LFEC In- spection (aft side), (a) Airplanes with 76,000 total flight cycles or more OR 9,500 flight cycles from last HFEC In- spection (forward side). (a) --Before further flight.Contact Boeing for repair instructions and do the re- pair. Any cracking or any incorrectly drilled or elongat- ed fastener hole(s) found. (a) In many areas the access is limited and you can do an inspection from only one side: either the forward side (HFEC) or the aft side (LFEC). In these areas, do the inspection from the side which provides access. 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. Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: June 17, 1999 737-53A1214Revision 5: January 30, 2015 38 of 77 BOEING SERVICE BULLETIN 737-53A1214 ALERTALERT ### Page 39 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 (ACO) has approved accomplishment of the inspection methods, locations, and repetitive inspection intervals as specified in Tables 1 through 8, Section 1.E of Revision 5 of this service bulletin as an alternative method of compliance (AMOC) to the corresponding requirements of paragraphs (g) through (q) of Airworthiness Directive (AD) 2012-18-13 R1. All provisions of this AD that are not specifically referenced in the preceding sentence remain fully applicable and must be complied with accordingly. The Manager of the FAA Seattle ACO approves the substitution of Service Bulletin 737-53A1214, Revision 5 as an AMOC to the use of Service Bulletin 737-53A1214, Revision 4, required by Paragraphs (r)(2), (r)(3), (r)(4), and (r)(5) of AD 2012-18-13 R1. All provisions of this AD that are not specifically referenced in the preceding sentence remain fully applicable and must be complied with accordingly. Operators should be aware that a number of SRM repairs which pertain to this Service Bulletin do not have AMOC approval statements for AD 98-11-04 R1, AD 2012-18-13 R1, AD 2008-08-23, and AD 2008-09-13. Until these SRMs are revised to include the appropriate AMOC approval statements, operators should request approval from the Boeing Company. When this Service Bulletin specifies contacting Boeing for repair instructions, the repair instructions must be approved by the FAA in accordance with paragraph (u) of AD 2012-18-13 R1, paragraph (i) of AD 98-11-04 R1, paragraph (l) of AD 2008-08-23, or paragraph (l) of AD 2008-09-13, as applicable. G. Manpower The table below shows an estimate of the man-hours necessary to do the inspections and modifications. This estimate is for direct labor only, done by an experienced crew. Adjust the estimate with operator man-hour data if necessary. The estimate does not include lost time. These are some examples of lost time: — Time to adjust to the workplace — Time to schedule the work — Time to examine the work — Time to cure the materials — Time to make the parts — Time to find the tools. Table 1A: Web Inspection at "Y" Chord - Option A: LFEC Inspection from the Aft Side of the Bulkhead Elapsed Time (Hours)Man-HoursNumber of PersonsTask 482LFEC Inspection 48TOTAL FOR EACH AIRPLANE Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: June 17, 1999 737-53A1214Revision 5: January 30, 2015 39 of 77 BOEING SERVICE BULLETIN 737-53A1214 ALERTALERT ### Page 40 Table 1B: Web Inspection at "Y" Chord - Option B: HFEC Inspection from the Forward Side of the Bulkhead Elapsed Time (Hours)Man-HoursNumber of PersonsTask 13262Access 1 (a)2 (a)2HFEC Inspect Web 16322Close Access 3060TOTAL FOR EACH AIRPLANE (a) Adding the NDT inspection below S-15 would take an additional 24 hours. Table 2: Web Inspection under Outer Circumferential Tear Strap and Detailed Inspection for Oil-Cans Elapsed HoursTask-HoursNumber of PersonsTask 7142LFEC Inspection and Detailed Inspection (a) 4 (b)8 (b)2Optional HFEC Inspection and Detailed Inspection (a) 714TOTAL FOR EACH AIRPLANE - LFEC OPTION 48TOTAL FOR EACH AIRPLANE - HFEC OPTION (a) The repeat oil-can Detailed Inspections would take 1 person 0.5 hours. (b) This estimate does not include access and close access for the forward side of the web. Refer to Table 1B for an estimate of the man-hours needed to get access and close access for the forward side of the bulkhead. Table 3: NDT Inspection of Bulkhead Lap Splices at the Center of the Bulkhead Elapsed HoursTask-HoursNumber of PersonsTask 3 (a)6 (a)2Inspection 36TOTAL FOR EACH AIRPLANE (a) This estimate does not include access and close access for the forward side of the web. Refer to Table 1B for an estimate of the man-hours needed to get access and close access for the forward side of the bulkhead. Table 4: NDT Inspection of "Z" Stiffeners at the Dome Cap Elapsed HoursTask-HoursNumber of PersonsTask 4 (a)8 (a)2Inspection Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: June 17, 1999 737-53A1214Revision 5: January 30, 2015 40 of 77 BOEING SERVICE BULLETIN 737-53A1214 ALERTALERT ### Page 41 Table 4: NDT Inspection of "Z" Stiffeners at the Dome Cap Elapsed HoursTask-HoursNumber of PersonsTask 48TOTAL FOR EACH AIRPLANE (a) This estimate does not include access and close access for the forward side of the web. Refer to Table 1B for an estimate of the man-hours needed to get access and close access for the forward side of the bulkhead. H. Weight and Balance Changes None. I. Electrical Load Data Not applicable. J. References 1. Existing Data: a. Engineering Change Memo PRR 35005-229R b. Boeing Service Bulletin 737-53-1123, 737-53A1075 c. Boeing Service Related Problem (SRP) 737-SRP-53-0109, 737-SRP-53-0116, 737-SRP-53-0155, 737-SRP-53-0417 d. Boeing Structural Item Interim Advisory (SIIA) 737-269, 737-52 e. Federal Aviation Administration (FAA) Airworthiness Directive (AD) 2008-08-23, 2008-09-13, 2012-18-13 R1, 98-11-04, 99-08-23 f. Service Bulletin Index D6-19567 g. 737 Non-Destructive Testing (NDT) Manual Part 6, 51-00-00, Part 6, 53-10-41, Part 6, 53-10-54, Part 6, 53-10-64, Part 6, 53-30-00 h. 737-100/200 Aircraft Maintenance Manual (AMM) 25-31-61, 25-40-0, 38-11-11 i. 737-100/200 Structural Repair Manual (SRM) 53-10-1, 53-10-11, 53-10-4 j. 737-300/400/500 Aircraft Maintenance Manual (AMM) 25-31-41, 25-40-01, 38-11-11 k. 737-300 Structural Repair Manual (SRM) 53-80-08 l. 737-400 Structural Repair Manual (SRM) 53-80-08 m. 737-500 Structural Repair Manual (SRM) 53-80-08 Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: June 17, 1999 737-53A1214Revision 5: January 30, 2015 41 of 77 BOEING SERVICE BULLETIN 737-53A1214 ALERTALERT ### Page 42 n. Boeing Service Letter 737-SL-51-042 2. Data Supplied with this Service Bulletin: None. 3. Installation Drawings Used in the Preparation of this Service Bulletin: TitleDrawing Number Bulkhead Installation - STA 101665-46568 Support Installation - Toilet Compartments Section 46 65-46812 These drawings were used to prepare this service bulletin. These drawings are not necessary to make the specified changes and are not supplied with this service bulletin. These drawings may not be applicable to all airplane configurations or operators. K. Publications Affected 1. Publications None. 2. Damage Tolerance Based Structural Inspections: Boeing has evaluated the repairs and/or changes in this service bulletin for effects on Fatigue Critical Structure (FCS) and for changes to Damage Tolerance Inspections (DTI) required in the Maintenance Program. This service bulletin affects FCS and new DTI requirements for the structure affected are contained in Paragraph 1.E., Compliance of this service bulletin. L. Interchangeability and Intermixability of Parts None. M. Software Accomplishment Summary Not affected. Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: June 17, 1999 737-53A1214Revision 5: January 30, 2015 42 of 77 BOEING SERVICE BULLETIN 737-53A1214 ALERTALERT ### Page 43 2. MATERIAL INFORMATION A. Material - Price and Availability None. B. Industry Support Information Boeing warranty remedies are not available for the inspection, and/or repair procedures given in this service bulletin. C. Parts Necessary for Each Airplane 1. Kits/Parts: None. 2. Parts and Materials Supplied by the Operator: None. 3. Parts Modified and Reidentified: None. 4. Parts Removed and Not Replaced: None. D. Parts Necessary to Change Spares None. E. Special Tooling - Price and Availability None. F. Special Tooling Necessary to do this Service Bulletin No special tools or equipment are necessary to do the change in this service bulletin. But, maintenance and overhaul tools in the manuals given in Paragraph 1.J., References, can be necessary. Examine operator tool supply to make sure all necessary tools are available. Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: June 17, 1999 737-53A1214Revision 5: January 30, 2015 43 of 77 BOEING SERVICE BULLETIN 737-53A1214 ALERTALERT ### Page 44 Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: June 17, 1999 737-53A1214Revision 5: January 30, 2015 44 of 77 BOEING SERVICE BULLETIN 737-53A1214 ALERTALERT BLANK PAGE ### Page 45 3. ACCOMPLISHMENT INSTRUCTIONS A. GENERAL INFORMATION CAUTION: KEEP THE WORK AREA, WIRES AND ELECTRICAL BUNDLES CLEAN OF METAL PARTICLES OR CONTAMINATION WHEN YOU USE TOOLS. UNWANTED MATERIAL, METAL PARTICLES OR CONTAMINATION CAUGHT IN WIRE BUNDLES CAN CAUSE DAMAGE TO THE BUNDLES. DAMAGED WIRE BUNDLES CAN CAUSE SPARKS OR OTHER ELECTRICAL DAMAGE. NOTE: 1. Manual titles are referred to by acronyms. Refer to Paragraph 1.J., References, for definition of the acronyms. 2. Obey all of the warnings and cautions given in the specified manual sections. 3. Unless shown differently, these dimensions and tolerances are used: – Linear dimensions are in inches – Tolerance on linear dimensions, other than rivet and bolt edge margins, is plus or minus 0.03 inch – Tolerance on rivet and bolt edge margin is plus or minus 0.05 inch – Angular tolerance is plus or minus 2 degrees – Hole dimensions for standard solid rivets and fasteners are in Structural Repair Manual (SRM) Chapter 51 – Torque limits to tighten nuts and bolts are in SRM Chapter 51 4. Use the approved fastener and process material substitutions in accordance with SRM Chapter 51. 5. If the length of any fastener specified in this service bulletin does not meet installation standards given in SRM Chapter 51, then a fastener of the same specification, or an approved substitute, with a length which meets the installation standards given in SRM Chapter 51 may be used. In addition, washers may be installed for fastener grip length in accordance with SRM Chapter 51. 6. A Detailed Inspection is defined as: An intensive examination of a specific item, installation, or assembly to detect damage, failure, or irregularity. Available lighting is normally supplemented with a direct source of good lighting at an intensity deemed appropriate. Inspection aids such as mirrors, magnifying lenses, etc. may be necessary. Surface cleaning and elaborate procedures may be required. 7. These work instructions refer to procedures included in other Boeing documents. When the words "refer to" are used and the operator has an accepted alternative procedure, the accepted alternative procedure can be used. When the words "in accordance with" are included in the instruction, the procedure in the Boeing document must be used. 8. Boeing Service Letter 737-SL-51-042, Damage Reporting and Repair Plan/Design Guidelines, is an acceptable procedure to request information from Boeing for additional structural repair instructions. The Service Letter describes what information must be provided to Boeing before a structural repair can be provided. Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: June 17, 1999 737-53A1214Revision 5: January 30, 2015 45 of 77 BOEING SERVICE BULLETIN 737-53A1214 ALERTALERT ### Page 46 9. If it is necessary to remove more parts for access, you can remove those parts. If you can get access without removing identified parts, it is not necessary to remove all of the identified parts. Jacking and shoring limitations must be observed. B. WORK INSTRUCTIONS PART I - NDT INSPECTION OF THE WEB AT THE "Y" CHORD - UPPER BULKHEAD FROM S-15L TO S-15R: 1. Do a Detailed Inspection and LFEC inspection of the aft side of the bulkhead web in accordance with Figure 1. As an option, you can do an inspection of the forward side of the bulkhead web in accordance with PART I - Step 3 (below). 2. If you find any cracking, or incorrectly drilled fastener hole or elongated fastener hole while you are doing the LFEC inspection and Detailed Inspection, you must get access to the forward side of the bulkhead and do a HFEC and Detailed Inspection of the section of web where the cracking, incorrectly drilled fastener hole or elongated fastener hole was found. Do the inspection in accordance with FIGURE 2 except the inspection can be limited to only the section of web with the damage. It is not necessary to do the inspection beyond the web splices of the web section containing the damage. 3. As an option to doing the LFEC inspection from the aft side of the bulkhead, you can do an inspection from the forward side of the bulkhead as follows: a. Get access to the forward side of the bulkhead by removing these items as necessary: (1) Remove the galley. Refer to 737-100/200 AMM 25-31-61 or 737-300/400/500 AMM 25-31-41 as an accepted procedure. (2) Remove the lavatory. Refer to 737-100/200 AMM 25-40-0 or 737-300/400/500 AMM 25-40-01 as an accepted procedure. b. Do an inspection of the forward side of the bulkhead in accordance with FIGURE 2. 4. If no cracking, incorrectly drilled fastener holes or elongated fastener holes are found, put the airplane back to a serviceable condition by replacing the aft galley and aft lavatory. Refer to the applicable AMM sections called out in PART I - Step 3 (above). NOTE: You can install the repair in accordance with 737-300 SRM 53-80-08, Repair 7 or 737-400 SRM 53-80-08, Repair 7 or 737-500 SRM 53-80-08, Repair 7 as a preventive modification. If the SRM repair is installed, do inspections at the times given in the SRM. 5. If you find any cracking, incorrectly drilled fastener holes or elongated fastener holes at S-6L or S-6R, cut out the damage and install a repair doubler in accordance with 737-100/200 SRM 53-10-4, Figure 15 or 737-300 SRM 53-80-08, Repair 7 or 737-400 SRM 53-80-08, Repair 7 or 737-500 SRM 53-80-08, Repair 7. If you find any cracking, incorrectly drilled fastener holes or elongated fastener holes in the web periphery at a location other than at S-6L or S-6R, contact Boeing for repair instructions and install the repair. Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: June 17, 1999 737-53A1214Revision 5: January 30, 2015 46 of 77 BOEING SERVICE BULLETIN 737-53A1214 ALERTALERT ### Page 47 NOTE: – More work is required on airplanes with any web cracking repaired in accordance with 737-100/200 SRM 53-10-4, Figure 3 or 737-300 SRM 53-80-08, Repair 1 or 737-400 SRM 53-80-08, Repair 1 or 737-500 SRM 53-80-08, Repair 1. If web cracking at the "Y" Chord was repaired using one of these figures, contact Boeing within 90 days of the release date of Revision 2 of this Service Bulletin to find out what additional work will be required. Please provide repair details when contacting Boeing. – If you install the repair in accordance with 737-100/200 SRM 53-10-4, Figure 15 or 737-300 SRM 53-80-08, Repair 7 or 737-400 SRM 53-80-08, Repair 7 or 737-500 SRM 53-80-08, Repair 7, do inspections at the times given in the SRM. 6. If you find any cracking, report it to the Boeing company. Include the crack location, length, and the airplane flight cycles and flight hours. Send the information to: BOEING COMMERCIAL AIRPLANE GROUP ATTENTION: MANAGER, AIRLINE SUPPORT 7. Do repeat inspections of unrepaired structure at the times shown in Paragraph 1.E., Compliance. NOTE: If you installed the repair in accordance with 737-100/200 SRM 53-10-4, Figure 15 or 737-300 SRM 53-80-08, Repair 7 or 737-400 SRM 53-80-08, Repair 7 or 737-500 SRM 53-80-08, Repair 7, do inspections at the times given in the SRM. 8. Put the airplane back to a serviceable condition. PART II - NDT INSPECTION UNDER CIRCUMFERENTIAL TEAR STRAP AND DETAILED INSPECTION FOR OIL-CANNING: 1. ONE-TIME NDT INSPECTION UNDER THE TEAR STRAP: a. From the aft side of the bulkhead, do a one-time LFEC inspection of the web under the outer circumferential tear strap in accordance with FIGURE 3. b. As an option to doing the LFEC inspection from the aft side, you can do a one-time HFEC inspection from the forward side in accordance with FIGURE 3. c. If you find any cracking under the outer circumferential tear strap, contact Boeing for repair instructions and do the repair. Do not repair in accordance with the SRM. 2. DETAILED INSPECTION FOR OIL-CANNING: a. At the times shown in Paragraph 1.E., Compliance, Table 4, accomplish a Detailed Inspection for oil canning from the aft side of the Bulkhead in accordance with FIGURE 5. b. If oil canning is found, accomplish the additional NDT inspections in accordance with the Allowable Damage Section in 737-100/200 SRM 53-10-1, Figure 1 or 737-300 SRM 53-80-08, Figure 101 or 737-400 SRM 53-80-08, Figure 101 or 737-500 SRM 53-80-08, Figure 101. If any cracking is found when inspecting the oil canning, or if any of the structural requirements listed in the SRM Notes cannot be met (for example: proximity to fasteners, damage to adjacent structure etc.), then contact Boeing for repair instructions and do the repair. c. Measure the depth and width of the oil can in accordance with the SRM Allowable Damage Section. If the oil can is within the limits of Graph I (lower curve) where repairs can be deferred, then choose one of the options that follow: Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: June 17, 1999 737-53A1214Revision 5: January 30, 2015 47 of 77 BOEING SERVICE BULLETIN 737-53A1214 ALERTALERT ### Page 48 (1) Option 1: Install the appropriate repair in accordance with Graph I of the SRM Allowable Damage Section in 737-100/200 SRM 53-10-1, Figure 1 or 737-300 SRM 53-80-08, Figure 101 or 737-400 SRM 53-80-08, Figure 101 or 737-500 SRM 53-80-08, Figure 101, within the time shown in Paragraph 1.E., Compliance. Repeat inspections are required until the repair is installed. Accomplish the inspection program in accordance with the SRM Allowable Damage Section. (2) Option 2: Install the appropriate repair in accordance with Graph I of the SRM Allowable Damage Section, before further flight. d. If the oil canning exceeds the limits of Graph I (lower curve) of the Allowable Damage Section in 737-100/200 SRM 53-10-1, Figure 1 or 737-300 SRM 53-80-08, Figure 101 or 737-400 SRM 53-80-08, Figure 101 or 737-500 SRM 53-80-08, Figure 101, then install the appropriate repair in accordance with Graph I, before further flight. e. Note that Graph I of the SRM Allowable Damage Section refers to two repairs, dependent upon the severity of the oil canning. These repairs are detailed below in Table 1. Table 1: SRM Repairs for the Aft Pressure Bulkhead 737-300 SRM 53-80-08 737-400 SRM 53-80-08 737-500 SRM 53-80-08 737-100/200 SRM 53-10-4Subject Repair 11Figure 3ABS 1016 Bulkhead Cutout Repair Repair 12Figure 5AOil Can Doubler Repair f. If an oil-can repair is installed as listed in Table 1 above, do inspections of the repair at the times in accordance with the SRM. g. After you install the SRM oil-can repair(s), verify that remaining oil-cans (if any) are within the allowable damage limits of the SRM. h. If you find any oil canning, report it to the Boeing company. Report the oil canning even if you are going to repair it in accordance with the SRM. Include the location, depth, size, orientation, and the airplane flight cycles and flight hours. Send the information to: BOEING COMMERCIAL AIRPLANE GROUP ATTENTION: MANAGER, AIRLINE SUPPORT i. Do repeat inspections of unrepaired structure for oil canning at the times shown in Paragraph 1.E., Compliance. j. Put the airplane back to a serviceable condition. PART III - NDT AND DETAILED INSPECTION OF THE WEB AT THE "Y" CHORD BELOW S-15 1. Get access to the forward side of the bulkhead by removing these items as necessary: a. Remove the galley. Refer to 737-100/200 AMM 25-31-61 or 737-300/400/500 AMM 25-31-41 as an accepted procedure. Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: June 17, 1999 737-53A1214Revision 5: January 30, 2015 48 of 77 BOEING SERVICE BULLETIN 737-53A1214 ALERTALERT ### Page 49 b. Remove the lavatory. Refer to 737-100/200 AMM 25-40-0 or 737-300/400/500 AMM 25-40-01. c. Remove the potable water tank. Refer to 737-100/200 AMM 38-11-11 or 737-300/400/500 AMM 38-11-11. 2. Do an inspection of the web from the forward or aft side of the bulkhead in accordance with FIGURE 4. NOTE: In many areas the access is limited and you can do an inspection from only one side: either the forward side (HFEC) or the aft side (LFEC). In these areas, do the inspection from the side which provides access. 3. If no cracking or no incorrectly drilled fastener holes or no elongated fastener holes are found, put the airplane back to a serviceable condition by replacing the galley, lavatory, and potable water tank, as necessary. Refer to the applicable AMM sections called out in PART III - Step 1 (above). If any cracking, incorrectly drilled fastener holes or elongated fastener holes are found, contact Boeing for repair instructions and do the repair. Report all cracking to the Boeing Company. Include the crack location, the length, and the airplane flight cycles and flight hours. Send the report to: BOEING COMMERCIAL AIRPLANE GROUP ATTENTION: MANAGER, AIRLINE SUPPORT NOTE: The 737-100/200 SRM 53-10-4, Figure 15 or 737-300 SRM 53-80-08, Figure 7 or 737-400 SRM 53-80-08, Figure 7 or 737-500 SRM 53-80-08, Repair 7 repair for cracking at S-6L and S-6R cannot be used at other stringer locations. 4. Do repeat inspections of unrepaired structure at the times shown in Paragraph 1.E., Compliance. 5. Put the airplane back to a serviceable condition. PART IV - NDT INSPECTION OF THE DOME CAP AT THE CENTER OF THE BULKHEAD 1. Do an inspection of the dome cap at the center of the bulkhead in accordance with FIGURE 6. a. If any cracking in the web is found, install the appropriate SRM repair, in accordance with Table 3, below. Table 3: SRM Repairs for the Apex Region of the Aft Pressure Bulkhead 737-300 SRM 53-80-08 737-400 SRM 53-80-08 737-500 SRM 53-80-08 737-100/200 SRM 53-10-11Subject Repair 9Figure 13BS 1016 Pressure Bulkhead Web Repair - Single Gore Web Repair 10Figure 14BS 1016 Pressure Bulkhead Web Repair - All Gore Webs b. Do inspections of the repair at the times given in the SRM. Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: June 17, 1999 737-53A1214Revision 5: January 30, 2015 49 of 77 BOEING SERVICE BULLETIN 737-53A1214 ALERTALERT ### Page 50 2. If no cracking is found, do repeat inspections of unrepaired structure at the times shown in Paragraph 1.E., Compliance. 3. Put the airplane back to a serviceable condition. PART V - NDT INSPECTION OF THE FORWARD FLANGE OF THE "Z" STIFFENERS AT THE DOME CAP 1. Do an inspection for any cracking in the "Z" stiffener flanges at the dome cap in the center of the bulkhead as in accordance with FIGURE 7. a. If any cracking in a "Z" stiffener flange is found, contact Boeing for repair instructions and install the repair. 2. If no cracking is found, do repeat inspections of unrepaired structure at the times shown in Paragraph 1.E., Compliance. 3. Put the airplane back to a serviceable condition. PART VI - DETAILED INSPECTION FOR EXISTING REPAIRS ON THE BULKHEAD 1. Do a detailed inspection of the bulkhead web and stiffeners to find existing repairs on the bulkhead. a. If no existing repair is found then no additional work is necessary. b. If an obsolete SRM repair is found then do eddy current inspections or repair replacement as necessary, in accordance with Paragraph 1.E., Compliance, Table 8. The obsolete SRM repairs are listed in Table 2 below and in Appendices A through E. NOTE: Refer to Appendices A through E to identify Obsolete SRM repairs. c. If a repair is installed in accordance with the SRM, then do eddy current inspections in accordance with the SRM. Do the inspections at the times specified in the SRM. d. If a non SRM repair is installed and the repair has FAA approved Damage Tolerance Inspections do the FAA approved Damage Tolerance Inspections. e. If a non SRM repair is installed and the repair does not have FAA approved Damage Tolerance Inspections contact Boeing for FAA approved Damage Tolerance Inspections and do the inspections. Do the inspections in accordance with paragraph 1.E Compliance, Table 7. Table 2: Obsolete SRM Repairs for the Aft Pressure Bulkhead Appendix737-300 SRM 53-80-08 737-400 SRM 53-80-08 737-500 SRM 53-80-08 737-100/200 SRM 53-10-4Subject A and BRepair 1Figure 3BS 1016 Bulkhead Cutout Re- pair CRepair 2Figure 5OIL CAN REPAIR Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: June 17, 1999 737-53A1214Revision 5: January 30, 2015 50 of 77 BOEING SERVICE BULLETIN 737-53A1214 ALERTALERT ### Page 51 Table 2: Obsolete SRM Repairs for the Aft Pressure Bulkhead Appendix737-300 SRM 53-80-08 737-400 SRM 53-80-08 737-500 SRM 53-80-08 737-100/200 SRM 53-10-4Subject DRepair 4Figure 12OIL CAN REPAIR BETWEEN TEAR STRAPS ERepair 5Figure 13OIL CAN REPAIR ACROSS TEAR STRAP 2. This step deleted at Revision 5. 3. Put the airplane back to a serviceable condition. Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: June 17, 1999 737-53A1214Revision 5: January 30, 2015 51 of 77 BOEING SERVICE BULLETIN 737-53A1214 ALERTALERT ### Page 52 (OCR) BOEING SERVICE BULLETIN 737-53A1214 ALERT ALERT FIN TERMINAL FITTINGS ACCESS DOOR BL S-3L S-3R OUTER CIRCUMFERENTIAL TEAR STRAP S-7L STEEL STRAPS _ S-7R (14 PLACES) S-10L - -S-10R S-15L- S-15R EDGE OF "Y" CHORD A-A VIEW LOOKING FORWARD S62128 FIGURE 1: LFEC INSPECTION OF THE WEB AT THE "Y" CHORD IN THE UPPER BULKHEAD FROM STRINGER S-15L TO S-15R (SHEET 1 OF 2) Original Issue: June 17, 1999 Revision 5 January 30, 2015 PROPRIETARY - Copyright © Unpublished Export Controlled ECCN: 9E991 - BOEING 737-53A1214 Work - See page 1 for details. 52 of 77 ### Page 53 The step numbers shown below agree with the numbers shown in the circle symbols in the figure. MORE DATAREFERENCESPROCEDURENAMETASKSTEP From the aft side, inspect the web at the aft fastener row of the "Y" chord/web interface in the upper fuselage from S-15L to S-15R. It is not necessary to inspect the web in the area of the steel straps. In accordance with 737 NDT Part 6, 53- 10-54. Low Frequency Eddy Current WebInspect1 Wherever you are doing the NDT in- spection, visually inspect along both fastener rows of the "Y" chord. Look for any cracking or any incorrectly drilled or elongated fastener holes. -Detailed Inspec- tion "Y" chord Inspect2 FIGURE 1: LFEC INSPECTION OF THE WEB AT THE "Y" CHORD IN THE UPPER BULKHEAD FROM STRINGER S-15L TO S-15R (SHEET 2 OF 2) Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: June 17, 1999 737-53A1214Revision 5 January 30, 2015 53 of 77 BOEING SERVICE BULLETIN 737-53A1214 ALERTALERT ### Page 54 (OCR) BOEING SERVICE BULLETIN 737-53A1214 ALERT ALERT FIN TERMINAL FITTING DOUBLER RADIAL STIFFENER (TYPICAL) BL S-3R O • S-3L OUTER CIRCUMFERENTIAL ACCESS DOOR TEAR STRAP B S-7R. _S-7L B S-11R - - S-11L S-15R- - S-15L SPLICE ANGLE (2 PLACES) S-21R ~s-21L FLOOR BEAM LEVELING COMPOUND A-A S62269 VIEW LOOKING AFT FIGURE 2: HFEC INSPECTION OF THE WEB AT THE "Y" CHORD IN THE UPPER BULKHEAD FROM STRINGER S-15L TO S-15R (SHEET 1 OF 2) Original Issue: June 17, 1999 Revision 5 January 30, 2015 Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished 737-53A1214 Work - See page 1 for details. 54 of 77 ### Page 55 The step numbers shown below agree with the numbers shown in the circle symbols in the figure. MORE DATAREFERENCESPROCEDURENAMETASKSTEP From the forward side, inspect the web at the aft fastener row in the up- per fuselage from S-15L to S-15R. In accordance with 737 NDT Part 6, 51- 00-00, Figure 4 or 23. High Frequency Eddy Current WebInspect1 NOTE: 1. Where a radial stiffener overlaps the "Y" chord at the perimeter of the web, you cannot get access to the web to inspect the fastener holes. Instead, use the reference NDT pro- cedure to inspect the web along the edge of the radial stiffener adjacent to the fastener holes that need to be inspected. Inspect the web for a distance of one inch each side of the fastener row. 2. Where the fin terminal fitting doublers overlap the web, use the reference NDT procedure to inspect the web along the edge of the doublers. Wherever you are doing the NDT in- spection, visually inspect along both fastener rows of the web. Look for any cracking or any incorrectly drilled or elongated fastener hole(s). -Detailed Inspec- tion WebInspect2 FIGURE 2: HFEC INSPECTION OF THE WEB AT THE "Y" CHORD IN THE UPPER BULKHEAD FROM STRINGER S-15L TO S-15R (SHEET 2 OF 2) Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: June 17, 1999 737-53A1214Revision 5 January 30, 2015 55 of 77 BOEING SERVICE BULLETIN 737-53A1214 ALERTALERT ### Page 56 (OCR) BOEING SERVICE BULLETIN 737-53A1214 ALERT ALERT BL OD TUAR STRAPUMFERENTIAL ACCESS DOOR S-7L →S-7R S-15L - — S-15R S-23L S-23R A-A VIEW LOOKING FORWARD FIGURE 3: ONE-TIME NDT INSPECTION OF WEB AT THE OUTER CIRCUMFERENTIAL TEAR STRAP (SHEET 1 OF 2) Original Issue: June 17, 1999 Revision 5 January 30, 2015 Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished 737-53A1214 Work - See page 1 for details. 56 of 77 ### Page 57 The step numbers shown below agree with the numbers shown in the circle symbols in the figure. MORE DATAREFERENCESPROCEDURENAMETASKSTEP From the aft side, inspect under the outer circumferential tear strap for any cracking in the web. As an option to doing this LFEC procedure, you can do the HFEC procedure shown in Step 2. In accordance with 737 NDT Part 6, 53- 10-41. Low Frequency Eddy Current WebInspect (a)1 Step 2 is optional to Step 1. From the forward side, inspect the web at the fasteners that attach the outer circumferential strap. In accordance with 737 NDT Part 6, 51- 00-00, Figure 4 or 23 High Frequency Eddy Current WebInspect (b)2 The NDT subject referenced in step 1 is an inspection of the web at the lap splices and at all three tear straps. You only need to inspect the outer tear strap. (a) Use Reference Standard A 389B. Contact Boeing if existing oil can repairs or bulging of the tear strap between fasteners prevents you from doing the LFEC inspection. Contact Boeing if existing oil can repairs prevent you from doing the HFEC inspection.(b) FIGURE 3: ONE-TIME NDT INSPECTION OF WEB AT THE OUTER CIRCUMFERENTIAL TEAR STRAP (SHEET 2 OF 2) Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: June 17, 1999 737-53A1214Revision 5 January 30, 2015 57 of 77 BOEING SERVICE BULLETIN 737-53A1214 ALERTALERT ### Page 58 (OCR) BOEING SERVICE BULLETIN 737-53A1214 ALERT ALERT ACCESS DOOR S-15R S-15L SPLICE ANGLE S-21R S-21L SPLICE ANGLE FLOOR BEAM 4) LEVELING COMPOUND A-A VIEW LOOKING AFT FRAME CHORD FRAME CHORD WEB WEB "Y" CHORD "Y" CHORD SPLICE ANGLE FWD C FWD C V09609 B-B C-C FIGURE 4: NDT INSPECTION OF WEB AT THE "Y" CHORD IN THE LOWER BULKHEAD FROM STRINGER S-15LTO S-15R (SHEET 1 OF 2) Original Issue: June 17, 1999 Revision 5 January 30, 2015 PROPRIETARY - Copyright © Unpublished Export Controlled ECCN: 9E991 - BOEING 737-53A1214 Work - See page 1 for details. 58 of 77 ### Page 59 The step numbers shown below agree with the numbers shown in the circle symbols in the figure. MORE DATAREFERENCESPROCEDURENAMETASKSTEP From the forward side, do a HFEC inspection of the web at the aft fastener row where possible. (a) The inspection from the forward side is not possible at: -the "Y" chord splice angle -the intersection of the floor structure and the "Y" chord -the bottom of the bulkhead where there is leveling compound covering the fasteners. In accordance with 737 NDT Part 6, 51- 00-00, Fig. 4 or 23 High Frequency Eddy Current (HFEC) WebInspect1 At these locations, do Step 3 and 4 instead. The LFEC inspection in Step 3 from the aft side is optional to a HFEC inspection from the forward side. However, the inspection inter- vals will be more frequent. Refer to Paragraph 1.E., Compliance. In accordance with 737 NDT Part 6, 53- 10-54. Low Frequency Eddy Current (LFEC) Wherever possible, visually inspect the forward side of the bulkhead along both fastener rows of the web. Look for any cracking or any incorrectly drilled or elongated fastener hole(s), or corrosion. -Detailed Inspec- tion WebInspect2 Wherever the HFEC inspection from the forward side is not possi- ble, do the LFEC inspection on the aft side of the bulkhead. In accordance with 737 NDT Part 6, 53- 10-54 Low Frequency Eddy Current WebInspect3 NOTE: 1. It is possible that the NDT manual shows an inspection area that is different than what is shown in this bulletin. Use the inspection area shown in this bulletin. 2. It is not possible to inspect the web adjacent to the stringer end-fittings because the NDT probe cannot fit under the fittings. Inspect the web along the edge of the leveling compound. -Detailed Inspec- tion WebInspect4 (a) Where a radial stiffener overlaps the "Y" chord at the perimeter of the web, you cannot get access to the web to inspect the fastener holes. Instead, use the reference NDT procedure to inspect the web along the edge of the radial stiffener adjacent to the fastener holes that need to be inspected. Inspect the web for a distance of one inch each side of the fastener row. FIGURE 4: NDT INSPECTION OF WEB AT THE "Y" CHORD IN THE LOWER BULKHEAD FROM STRINGER S-15LTO S-15R (SHEET 2 OF 2) Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: June 17, 1999 737-53A1214Revision 5 January 30, 2015 59 of 77 BOEING SERVICE BULLETIN 737-53A1214 ALERTALERT ### Page 60 (OCR) BOEING SERVICE BULLETIN 737-53A1214 ALERT ALERT BL ACCESS DOOR DWEB S-7L _S-7R S-15L - -S-15R S-23L A-A S-23R W55312 VIEW LOOKING FORWARD FIGURE 5: DETAILED INSPECTION FOR OIL-CAN DAMAGE IN THE BULKHEAD WEB (SHEET 1 OF 2) Original Issue: June 17, 1999 Revision 5 January 30, 2015 Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished 737-53A1214 Work - See page 1 for details. 60 of 77 The text continues at https://openairdocs.org/service-documents/boeing/737-53a1214/file/6e6ffdf53949.md?from=61 --- OpenAirDocs.org is an independent research project of [Contrail Labs](https://contraillabs.com/). It is not affiliated with the FAA or the NTSB. Source documents are U.S. government works in the public domain, except the copies of manufacturers’ service documents, which belong to their rights holders.