# Boeing Alert Service Bulletin 737-53A1301: The Boeing Company - Service Bulletin - Rights: © The Boeing Company. Filed by the FAA in regulations.gov docket FAA-2011-0914; AD 2011-24-12 incorporates this document by reference. Not covered by OpenAirDocs’ CC0 dedication. - Document: [Boeing Alert Service Bulletin 737-53A1301](https://openairdocs.org/service-documents/boeing/737-53a1301.md) - Title as filed: The Boeing Company - Service Bulletin - Pages: 240 - PDF: https://openairdocs.org/files/sha256/b4/53/b45327fbb15c8282dbfaf7917e1cef782d843e5e5243edbf01ce1a8cf38eaa2f - Page: https://openairdocs.org/service-documents/boeing/737-53a1301/file/b45327fbb15c ## 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: 737-53A1301 Original Issue: September 03, 2009 Revision 1: June 07, 2010 ATA System: 5331 SUBJECT: FUSELAGE - Skin - Cracks at Chem-milled Steps in Crown Skins at Specified Locations - Inspection Export of this technology is controlled under the United States Export Administration Regulations (EAR) (15 CFR 730-774). 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all export laws. 9E991ECCN: BOEING PROPRIETARY, CONFIDENTIAL, AND/OR TRADE SECRET Copyright © 2009 The Boeing Company Unpublished Work - All Rights Reserved Boeing claims copyright in each page of this document only to the extent that the page contains copyrightable subject matter. Boeing also claims copyright in this document as a compilation and/or collective work. This document includes proprietary information owned by The Boeing Company and/or one or more third parties. Treatment of the document and the information it contains is governed by contract with Boeing. For more information, contact The Boeing Company, P.O. Box 3707, Seattle, Washington 98124. 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, KDC-10, MD-10, MD-11, MD-80, MD-88, MD-90, P-8A, Poseidon and the Boeing livery 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. BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: September 03, 2009 737-53A1301Revision 1: June 07, 2010 1 of 240 4.0 ### Page 2 BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: September 03, 2009 737-53A1301Revision 1: June 07, 2010 2 of 240 BOEING SERVICE BULLETIN 737-53A1301 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 7 B. Concurrent Requirements ...................................... 2 7 C. Reason ................................................ 2 8 D. Description .............................................. 2 9 E. Compliance .............................................. 3 0 F. Approval ............................................... 3 8 G. Manpower .............................................. 3 9 H. Weight and Balance Changes .................................... 4 4 I. Electrical Load Data ......................................... 4 4 J. References .............................................. 4 4 1. Existing Data .......................................... 4 4 2. Data supplied with this Service Bulletin ............................ 4 5 3. Installation Drawings Used in the Preparation of this Service Bulletin ............ 4 5 K. Publications Affected ........................................ 4 5 L. Interchangeability and Intermixability of Parts ........................... 4 6 2. MATERIAL INFORMATION ........................................ 4 7 A. Material - Price and Availability ................................... 4 7 B. Industry Support Information .................................... 4 7 C. Parts Necessary For Each Airplane ................................. 4 7 1. Kits/Parts ............................................ 4 7 2. Parts and Materials Supplied by the Operator ........................ 4 7 3. Parts Modified and Reidentified ................................ 4 7 4. Parts Removed and Not Replaced .............................. 4 7 D. Parts Necessary to Change Spares ................................. 4 7 E. Special Tooling - Price and Availability ............................... 4 7 F. Special Tooling Necessary to do this Service Bulletin ....................... 4 7 3. ACCOMPLISHMENT INSTRUCTIONS .................................. 4 9 A. GENERAL INFORMATION ..................................... 4 9 B. WORK INSTRUCTIONS ....................................... 4 9 FIGURE 1: FUSELAGE - SKIN AT AREAS WITH DOUBLER PROVISIONS FOR GROUP 1 AIRPLANES - NON DESTRUCTIVE INSPECTION [Group 1] ....................... 6 0 FIGURE 2: FUSELAGE - SKIN AT AREAS WITH DOUBLER PROVISIONS FOR GROUP 2 AIRPLANES - NON DESTRUCTIVE INSPECTION [Group 2] ....................... 6 2 FIGURE 3: FUSELAGE - SKIN AT AREAS WITH DOUBLER PROVISIONS FOR GROUP 3 AIRPLANES - NON DESTRUCTIVE INSPECTION [Group 3] ....................... 6 8 FIGURE 4: FUSELAGE - SKIN AT AREAS WITH DOUBLER PROVISIONS FOR GROUP 4 AIRPLANES - NON DESTRUCTIVE INSPECTION [Group 4] ....................... 7 4 FIGURE 5: FUSELAGE - SKIN AT AREAS WITH DOUBLER PROVISIONS FOR GROUP 5 AIRPLANES - NON DESTRUCTIVE INSPECTION [Group 5] ....................... 7 9 FIGURE 6: FUSELAGE - SKIN AT AREAS WITH DOUBLER PROVISIONS FOR GROUP 6 AIRPLANES - NON DESTRUCTIVE INSPECTION [Group 6] ....................... 8 3 BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: September 03, 2009 737-53A1301Revision 1: June 07, 2010 3 of 240 BOEING SERVICE BULLETIN 737-53A1301 ALERTALERT ### Page 4 FIGURE 7: FUSELAGE - SKIN AT AREAS WITH DOUBLER PROVISIONS FOR GROUP 7 AIRPLANES - NON DESTRUCTIVE INSPECTION [Group 7] ....................... 8 9 FIGURE 8: FUSELAGE - SKIN AT AREAS WITH DOUBLER PROVISIONS FOR GROUP 8 AIRPLANES - NON DESTRUCTIVE INSPECTION [Group 8] ....................... 9 5 FIGURE 9: FUSELAGE - SKIN AT AREAS WITH DOUBLER PROVISIONS FOR GROUP 9 AIRPLANES - NON DESTRUCTIVE INSPECTION [Group 9] ...................... 1 0 1 FIGURE 10: FUSELAGE - SKIN AT AREAS WITH DOUBLER PROVISIONS FOR GROUP 10 AIRPLANES - NON DESTRUCTIVE INSPECTION [Group 10] ...................... 1 0 7 FIGURE 11: FUSELAGE - SKIN AT AREAS WITH DOUBLER PROVISIONS FOR GROUP 11 AIRPLANES - NON DESTRUCTIVE INSPECTION [Group 11] ...................... 1 1 3 FIGURE 12: FUSELAGE - SKIN AT AREAS WITH DOUBLER PROVISIONS FOR GROUP 12 AIRPLANES - NON DESTRUCTIVE INSPECTION [Group 12] ...................... 1 1 8 FIGURE 13: FUSELAGE - SKIN AT AREAS WITH DOUBLER PROVISIONS FOR GROUP 13 AIRPLANES - NON DESTRUCTIVE INSPECTION [Group 13] ...................... 1 2 2 FIGURE 14: FUSELAGE - SKIN AT AREAS WITH DOUBLER PROVISIONS FOR GROUP 14 AIRPLANES - NON DESTRUCTIVE INSPECTION [Group 14] ...................... 1 3 1 FIGURE 15: FUSELAGE - SKIN AT AREAS WITH DOUBLER PROVISIONS FOR GROUP 15 AIRPLANES - NON DESTRUCTIVE INSPECTION [Group 15] ...................... 1 4 2 FIGURE 16: FUSELAGE - SKIN AT AREAS WITH DOUBLER PROVISIONS FOR GROUP 16 AIRPLANES - NON DESTRUCTIVE INSPECTION [Group 16] ...................... 1 5 2 FIGURE 17: FUSELAGE - SKIN AT AREAS WITH DOUBLER PROVISIONS FOR GROUP 17 AIRPLANES - NON DESTRUCTIVE INSPECTION [Group 17] ...................... 1 6 2 FIGURE 18: FUSELAGE - SKIN AT AREAS WITH DOUBLER PROVISIONS FOR GROUP 18 AIRPLANES - NON DESTRUCTIVE INSPECTION [Group 18] ...................... 1 6 9 FIGURE 19: FUSELAGE - SKIN AT AREAS WITH DOUBLER PROVISIONS FOR GROUP 19 AIRPLANES - NON DESTRUCTIVE INSPECTION [Group 19] ...................... 1 7 7 FIGURE 20: FUSELAGE - SKIN AT AREAS WITH DOUBLER PROVISIONS FOR GROUP 20 AIRPLANES - NON DESTRUCTIVE INSPECTION [Group 20] ...................... 1 8 6 FIGURE 21: FUSELAGE - SKIN AT AREAS WITH DOUBLER PROVISIONS FOR GROUP 21 AIRPLANES - NON DESTRUCTIVE INSPECTION [Group 21] ...................... 1 9 6 FIGURE 22: FUSELAGE - SKIN AT AREAS WITH DOUBLER PROVISIONS FOR GROUP 22 AIRPLANES - NON DESTRUCTIVE INSPECTION [Group 22] ...................... 2 0 6 FIGURE 23: FUSELAGE - SKIN AT AREAS WITH DOUBLER PROVISIONS FOR GROUP 23 AIRPLANES - NON DESTRUCTIVE INSPECTION [Group 23] ...................... 2 1 6 FIGURE 24: FUSELAGE - SKIN AT AREAS WITH DOUBLER PROVISIONS FOR GROUP 24 AIRPLANES - NON DESTRUCTIVE INSPECTION [Group 24] ...................... 2 2 4 FIGURE 25: FUSELAGE - SKIN AT AREAS WITH DOUBLER PROVISIONS FOR GROUP 25 AIRPLANES - NON DESTRUCTIVE INSPECTION [Group 25] ...................... 2 3 2 APPENDIX A: NDI INSPECTION DETAIL .................................. 2 4 0 BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: September 03, 2009 737-53A1301Revision 1: June 07, 2010 4 of 240 BOEING SERVICE BULLETIN 737-53A1301 ALERTALERT ### Page 5 Commercial Airplanes 737 Service Bulletin ALERT Revision Transmittal SheetNumber: 737-53A1301Original Issue: September 03, 2009 Revision 1: June 07, 2010 ATA System: 5331 SUBJECT: FUSELAGE - Skin - Cracks at Chem-milled Steps in Crown Skins at Specified Locations - Inspection This revision includes all pages of the service bulletin. COMPLIANCE INFORMATION RELATED TO THIS REVISION More work is necessary on airplanes that have accomplished the initial release of this Service Bulletin. Airplanes were added to this service bulletin effectivity. Airplanes that were in Group 1 are now in Group 2 or Group 8 or Group 10. Airplanes that were in Group 2 are now in Group 13 or Group 14 or Group 15 or Group 16 or Group 17 or Group 18 or Group 21 or Group 22 or Group 23 or Group 24 or Group 25. REASON FOR REVISION This revision is sent to add additional crown skin inspection areas and 737-200/-200C/-300/-400/-500 airplanes. These sections were changed: 1. Summary BACKGROUND: Paragraphs 1 and 2 revised and service history table added 2. Summary ACTION: Paragraphs 1 and 2 revised and 3 added 3. Summary EFFECTIVITY: 737-200/-200C airplanes and all 737-300/-400/-500 airplanes without ELT antenna provisions added 4. Summary COMPLIANCE: AD added 5. Summary MANPOWER: Added groups 3 through 25 and revised the Total Task Hours and Elapsed Hours in groups 1 and 2 6. Summary ILLUSTRATION: Updated 7. Section 1.A.1. Effectivity: Group Configuration table revised and groups 3 through 26 added 8. Section 1.C. Reason: Paragraphs 1 and 2 revised and service history table added 9. Section 1.D. Description: Paragraphs 1 and 2 revised and Affected Maintenance Zones tables revised 10. Section 1.E. Compliance: Table 1, revised: Tables 2, 3 and 4 added BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: September 03, 2009 737-53A1301Revision 1: June 07, 2010 5 of 240 ### Page 6 11. Section 1.F. Approval: Alternate Means of Compliance (AMOC) paragraph added 12. Section 1.G. Manpower: Revised tables 1 and 2 and added tables 3 through 25 13. Section 1.J. References: Added 1.J.1.c., 1.J.1.d. and revised the table in 1.J.3 14. Section 3.A. GENERAL INFORMATION: Added NOTEs 4, 7 and 8 15. Section 3.B. WORK INSTRUCTIONS: revised to add steps 1 through 26 16. FIGURES: Figures 1 and 2 revised and Figures 3 through 25 added 17. APPENDIX: Added Appendix A. Vertical lines are put on the left edge of each page, except in Paragraph 1.A., Effectivity, to show the location of important changes. Pages with no vertical lines have no important changes. REVISION HISTORY September 03, 2009Original Issue: June 07, 2010Revision 1: BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: September 03, 2009 737-53A1301Revision 1: June 07, 2010 6 of 240 BOEING SERVICE BULLETIN 737-53A1301 ALERTALERT ### Page 7 Commercial Airplanes 737 Service Bulletin ALERT SummaryNumber: 737-53A1301Original Issue: September 03, 2009 Revision 1: June 07, 2010 ATA System: 5331 SUBJECT: FUSELAGE - Skin - Cracks at Chem-milled Steps in Crown Skins at Specified Locations - Inspection 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 Accomplishment of the inspections in this service bulletin will make sure that fuselage crown skin cracks at horizontal chem-mill steps at specified locations between Body Stations 259.5 and Body Stations 1016 and between stringers S-10L and S-10R are found and repaired. All airplanes listed in this service bulletin require inspection. This action is necessary to find and repair fatigue cracking of the skin panel at the specified chem-mill step locations which could result in rapid decompression of the airplane. Boeing received a report from an operator of a hole in the fuselage skin common to stringer S-1 and S-2L, between STA 827 and STA 847. The crack started along the chem-mill edge along stringer S-1. The airplane skin in the area had 20 inch tear strap bays. The airplane diverted to an alternate airport due to cabin depressurization and subsequent deployment of the oxygen masks. The airplane had accumulated 42,569 total flight cycles. Airplanes with 10 inch tear strap bays are also susceptible to cracks at this location. The cause of cracking is under investigation. After the release of the original issue of this service bulletin additional crack indications have been reported. Boeing Service Related Problem (SRP) 737-SRP-53-0346 is related to this service bulletin. Service History Reports of cracks in crown skinsFlight HoursFlight CyclesStringerStation 3 reports, above the forward entry door, on air- planes with 10 inch tear strap bays, in Groups 1-12 of this service bulletin. 66132-7467063725-698452-LSTA 342-348 One report at MLS antenna provision, on air- planes with 20 inch tear strap bays, in Groups 13-25 of this service bulletin. 51899435561-LSTA 470 BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: September 03, 2009 737-53A1301Revision 1: June 07, 2010 7 of 240 ### Page 8 Service History Reports of cracks in crown skinsFlight HoursFlight CyclesStringerStation 3 reports at ADF antenna provision, on airplanes with 20 inch tear strap bays, in Groups 13-25 of this service bulletin. 51964-5330443690-448151-LSTA 510 One report at HF antenna provision, on air- planes with 10 inch tear strap bays, in Groups 1-12 of this service bulletin. 49627447572-LSTA 581 Two reports at ELT antenna provision, on air- planes with 20 inch tear strap bays, in Groups 13-25 of this service bulletin. 50883-5276242569-443932-L and 2-RSTA827 8 reports, above the aft galley door, on airplanes with 10 inch tear strap bays, in Groups 1-12 of this service bulletin. 66989-7573563998-711295-RSTA 947-1006 5 reports, above the aft galley door, on airplanes with 20 inch tear strap bays, in Groups 13-25 of this service bulletin. 41259-4928536187-414095-RSTA 947-1006 ACTION Group 1-25: Get external access to the specified locations. Group 1-25: Do an external Detailed Inspection and one of the external Non Destructive Inspection (NDI) specified in the compliance section of this service bulletin for cracking in the fuselage skin along the chem-mill steps at the specified locations. The NDI that can be used are Medium Frequency Eddy Current (MFEC), Magneto Optical Imaging (MOI), C-Scan or Ultrasonic Phased Array (UTPA). If any crack is found, contact Boeing for repair instructions and do the repair. If no cracking is found, do the repeat inspection in accordance with this service bulletin. Group 26: Operators with Group 26 airplanes should contact Boeing to obtain engineering and accomplishment instructions for this inspection. EFFECTIVITY 737-200/-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 2010-01-09 is related to this service bulletin. Refer to Paragraph 1.E. Compliance. INDUSTRY SUPPORT INFORMATION At the time of release of this service bulletin, warranty remedies have not been determined. A subsequent revision or Information Notice will address the warranty remedies available, if any. BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: September 03, 2009 737-53A1301Revision 1: June 07, 2010 8 of 240 BOEING SERVICE BULLETIN 737-53A1301 ALERTALERT ### Page 9 MANPOWER Elapsed HoursTotal Task HoursAirplanes 1.001.50Group 1 4.257.00Group 2 4.257.00Group 3 3.505.50Group 4 3.255.00Group 5 4.006.50Group 6 3.505.50Group 7 4.257.00Group 8 4.257.00Group 9 5.008.50Group 10 3.756.00Group 11 3.255.00Group 12 7.0020.50Group 13 7.7523.50Group 14 9.2529.50Group 15 9.0028.50Group 16 4.5013.50Group 17 5.7518.50Group 18 8.0024.50Group 19 8.0024.50Group 20 8.5026.50Group 21 8.2525.50Group 22 8.2525.50Group 23 8.2525.50Group 24 8.2525.50Group 25 MATERIAL INFORMATION None. BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: September 03, 2009 737-53A1301Revision 1: June 07, 2010 9 of 240 BOEING SERVICE BULLETIN 737-53A1301 ALERTALERT ### Page 10 (OCR) BOEING SERVICE BULLETIN 737-53A1301 ALERT ALERT STA 1016 DO AN MFEC INSPECTION, OR AN MOI INSPECTION, OR A C-SCAN INSPECTION OR AN ULTRASONIC PHASED STA 827 ARRAY INSPECTION FOR CRACKING OF THE FUSELAGE SKIN ALONG THE CHEM-MILL LINES AT THE SPECIFIED LOCATIONS. IF ANY CRACK IS FOUND 259.5 STA 0000000000000000 CONTACT BOEING FOR REPAIR INSTRUCTIONS AND INSTALL THE REPAIR. > S-10R S-10L SKIN AND DOUBLER - EMERGENCY LOCATOR TRANSMITTER ANTENNA LOCATION STA STA STA 827 847 867 S-2R - TYPICAL CRACK S-1 - S-2L - DORSAL FIN FWD DOUBLER FAIRING NDI INSPECTION AREA EXAMPLE LOCATION 20 INCH TEAR STRAP DOUBLER SHOWN (ELT ANTENNA SKIN PROVISION) 1878015 10 INCH TEAR STRAP DOUBLER ALMOST THE SAME Original Issue: September 03, 2009 Revision 1: June 07, 2010 737-53A1301 BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. 10 of 240 ### Page 11 Commercial Airplanes 737 Service Bulletin ALERT Number: 737-53A1301 Original Issue: September 03, 2009 Revision 1: June 07, 2010 ATA System: 5331 SUBJECT: FUSELAGE - Skin - Cracks at Chem-milled Steps in Crown Skins at Specified Locations - Inspection 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 Document D6-19567 Part 3 for Airplane Variable Number, Line Number, and Serial Number data. DESCRIPTIONCONFIGURATIONGROUP 737-200 and 737-200C Airplanes line number 292 through 1585 with HF Antenna provisions -1 737-300 Airplanes with ELT Antenna provisions and 10 inch tear strap bays -2 737-300 Airplanes with MLS Antenna provisions and 10 inch tear strap bays -3 737-300 Airplanes with no ELT or MLS Antenna provisions and 10 inch tear strap bays -4 737-300 Airplanes with no ELT or MLS Antenna provisions and no 10 inch tear strap bays from STA 540 to STA 727E at S-10L and S-10R -5 737-400 Airplanes with MLS Antenna provisions and 10 inch tear strap bays -6 BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: September 03, 2009 737-53A1301Revision 1: June 07, 2010 11 of 240 ### Page 12 DESCRIPTIONCONFIGURATIONGROUP 737-400 Airplanes with no MLS Antenna provisions and 10 inch tear strap bays -7 737-500 Airplanes with ELT Antenna provisions and 10 inch tear strap bays -8 737-500 Airplanes with MLS Antenna provisions and 10 inch tear strap bays -9 737-500 Airplanes with ELT and MLS Antenna provisions and 10 inch tear strap bays -10 737-500 Airplanes with no ELT or MLS Antenna provisions and 10 inch tear strap bays -11 737-500 Airplanes with no ELT or MLS Antenna provisions and no 10 inch tear strap bays from STA 540 to STA 727E at S-10L and S-10R -12 737-300 Airplanes with ELT and other Antenna provisions, no SATCOM Antenna provisions and 20 inch tear strap bays -13 737-300 Airplanes with ELT, SATCOM and other Antenna provisions, unique aft galley door skin pad-up and 20 inch tear strap bays -14 737-300 Airplanes with ELT, SATCOM and other Antenna provisions, unique aft galley door skin pad-up and 20 inch tear strap bays -15 737-300 Airplanes with ELT, SATCOM and other Antenna provisions, unique aft galley door skin pad-up and 20 inch tear strap bays -16 737-300 Airplanes with ELT, and other Antenna provisions, no SATCOM Antenna provisions, no 20 inch tear strap bays from STA 540 to STA 727 at S-10L and S-10R -17 737-300 Airplanes with ELT, SATCOM and other Antenna provisions, no 20 inch tear strap bays from STA 540 to STA 727 at S-10L and S-10R -18 737-400 Airplanes with no ELT Antenna provisions, with other Antenna provisions and 20 inch tear strap bays -19 737-400 Airplanes with no ELT Antenna provisions, with other Antenna provisions, unique aft galley door bear skin pad-up and 20 inch tear strap bays -20 BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: September 03, 2009 737-53A1301Revision 1: June 07, 2010 12 of 240 BOEING SERVICE BULLETIN 737-53A1301 ALERTALERT ### Page 13 DESCRIPTIONCONFIGURATIONGROUP 737-400 Airplanes with ELT Antenna provisions and other Antenna provisions, unique aft galley door skin pad-up and 20 inch tear strap bays -21 737-400 Airplanes with ELT Antenna provisions and other Antenna provisions, unique aft galley door skin pad-up and 20 inch tear strap bays -22 737-500 Airplanes with ELT Antenna provisions and other Antenna provisions and 20 inch tear strap bays -23 737-500 Airplanes with ELT Antenna provisions and other Antenna provisions, unique aft galley door skin pad-up and 20 inch tear strap bays -24 737-500 Airplanes with ELT Antenna provisions and other Antenna provisions, unique aft service galley door skin pad-up and 20 inch tear strap bays -25 737-200 AND 737-200C Airplanes line number 1 through 291 with HF Antenna provisions -26 Airplane Models: 737-200, 737-200C, 737-300, 737-400, 737-500 GroupVariable Number 26PG001 - PG075 26PG199 26PG201 - PG230 26PG251 - PG255 26PG271 - PG279 26PG301 - PG314 26PG331 - PG332 26PG351 - PG356 26PG375 26PG401 - PG403 26PG431 - PG442 26PG471 - PG475 26PG501 - PG505 26PG571 - PG583 BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: September 03, 2009 737-53A1301Revision 1: June 07, 2010 13 of 240 BOEING SERVICE BULLETIN 737-53A1301 ALERTALERT ### Page 14 GroupVariable Number 1PG584 - PG586 26PG621 - PG630 26PG651 - PG652 26PG701 - PG705 1PH001 1PH011 - PH013 1PH021 - PH024 26PH701 - PH715 26PH731 - PH732 26PH741 - PH742 1PH743 26PJ001 - PJ002 1PJ003 - PJ009 26PJ031 - PJ032 26PJ071 - PJ072 26PJ101 - PJ104 1PJ105 - PJ119 7PJ301 - PJ302 7PJ551 19PJ552 - PJ559 20PJ560 - PJ561 20PJ601 - PJ603 22PJ604 - PJ615 20PJ811 20PJ816 - PJ817 1PK026 - PK029 1PK041 - PK053 1PK061 - PK070 1PK081 - PK082 1PK091 - PK099 1PK101 - PK103 1PK111 - PK120 1PK141 - PK146 BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: September 03, 2009 737-53A1301Revision 1: June 07, 2010 14 of 240 BOEING SERVICE BULLETIN 737-53A1301 ALERTALERT ### Page 15 GroupVariable Number 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 1PK621 - PK637 1PK641 - PK642 1PK661 - PK666 1PK671 - PK681 1PK691 - PK697 1PK711 - PK716 1PK731 - PK765 1PK771 - PK779 1PK801 - PK804 1PK819 - PK827 BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: September 03, 2009 737-53A1301Revision 1: June 07, 2010 15 of 240 BOEING SERVICE BULLETIN 737-53A1301 ALERTALERT ### Page 16 GroupVariable Number 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 1PL601 - PL603 1PL611 1PL621 - PL626 1PL631 - PL632 26PL711 - PL712 26PL716 1PL717 - PL747 1PL756 1PL758 1PL761 - PL770 BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: September 03, 2009 737-53A1301Revision 1: June 07, 2010 16 of 240 BOEING SERVICE BULLETIN 737-53A1301 ALERTALERT ### Page 17 GroupVariable Number 1PL781 - PL788 1PL793 26PL801 - PL803 1PM001 - PM006 1PM016 - PM017 1PM021 - PM023 1PM051 - PM066 1PM101 - PM119 1PM141 - PM142 1PM171 1PM181 1PM251 - PM255 1PM281 - PM283 4PM381 - PM399 4PM401 - PM417 4PM541 - PM542 13PM543 - PM550 7PM551 - PM564 1PN001 - PN002 1PN021 - PN043 1PN081 - PN086 1PN101 - PN117 1PN131 - PN163 1PN401 - PN420 1PN431 - PN433 1PN451 - PN456 1PN471 - PN474 1PN481 1PN491 - PN493 1PN501 - PN502 1PN511 - PN512 1PN521 4PP001 - PP054 BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: September 03, 2009 737-53A1301Revision 1: June 07, 2010 17 of 240 BOEING SERVICE BULLETIN 737-53A1301 ALERTALERT ### Page 18 GroupVariable Number 4PP101 - PP126 5PP127 - PP160 4PP161 - PP169 4PP181 - PP199 4PP201 - PP205 4PP221 4PP231 - PP243 4PP281 - PP286 4PP301 - PP305 4PP351 - PP353 4PP376 - PP384 4PP391 - PP393 4PP401 - PP440 4PP471 - PP475 4PP501 - PP517 13PP518 - PP520 4PP521 - PP522 4PP631 - PP634 4PP651 - PP652 4PP671 - PP699 4PP701 - PP733 4PP771 - PP779 4PP801 - PP804 3PP805 - PP808 4PP821 - PP827 4PP831 - PP848 4PP851 - PP852 4PP861 - PP875 15PP876 - PP877 4PP891 - PP899 4PP901 - PP936 4PP946 - PP948 4PP951 - PP952 BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: September 03, 2009 737-53A1301Revision 1: June 07, 2010 18 of 240 BOEING SERVICE BULLETIN 737-53A1301 ALERTALERT ### Page 19 GroupVariable Number 4PP961 - PP967 4PP981 - PP991 4PP993 4PQ001 - PQ016 4PQ026 - PQ041 4PQ051 - PQ092 4PQ101 - PQ199 4PQ201 - PQ202 4PQ221 - PQ237 4PQ241 - PQ243 4PQ251 - PQ267 4PQ281 - PQ296 13PQ297 - PQ299 4PQ301 - PQ307 4PQ331 - PQ332 4PQ341 - PQ344 13PQ345 - PQ346 14PQ347 - PQ348 4PQ361 - PQ369 13PQ370 - PQ372 14PQ373 14PQ391 - PQ393 16PQ394 - PQ395 4PQ401 - PQ407 13PQ408 - PQ410 4PQ411 - PQ413 13PQ414 15PQ415 - PQ418 4PQ421 13PQ431 - PQ437 14PQ438 14PQ447 15PQ448 BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: September 03, 2009 737-53A1301Revision 1: June 07, 2010 19 of 240 BOEING SERVICE BULLETIN 737-53A1301 ALERTALERT ### Page 20 GroupVariable Number 15PQ451 16PQ454 4PQ471 - PQ472 13PQ473 - PQ474 14PQ475 4PQ479 - PQ481 4PQ486 - PQ487 4PQ491 - PQ493 4PQ771 13PQ772 4PQ791 - PQ793 3PQ801 - PQ805 2PQ931 - PQ932 13PQ933 - PQ935 14PQ951 14PQ971 15PQ972 - PQ985 16PQ986 - PQ995 15PQ996 - PQ997 15PR001 - PR006 16PR007 - PR017 15PR021 - PR024 16PR025 - PR030 15PR031 - PR032 16PR033 - PR034 15PR041 - PR044 16PR045 15PR061 16PR062 - PR072 16PR077 - PR082 16PR091 - PR092 15PR096 16PR101 BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: September 03, 2009 737-53A1301Revision 1: June 07, 2010 20 of 240 BOEING SERVICE BULLETIN 737-53A1301 ALERTALERT ### Page 21 GroupVariable Number 16PR121 - PR122 16PR131 - PR132 16PR141 - PR143 16PR161 - PR172 16PR181 4PS601 - PS616 13PS617 - PS625 14PS626 - PS629 15PS630 4PS631 3PS636 - PS638 4PS641 - PS644 4PS651 - PS657 4PS666 - PS669 4PS691 - PS692 4PS701 - PS703 13PS704 - PS706 5PS751 - PS762 17PS763 - PS794 18PS795 - PS799 13PS811 13PS836 - PS837 13PS841 - PS845 14PS846 13PS851 - PS852 13PS856 13PS861 14PS862 - PS863 13PS866 - PS868 15PS871 - PS872 16PS873 - PS874 14PS896 - PS897 18PS901 - PS906 BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: September 03, 2009 737-53A1301Revision 1: June 07, 2010 21 of 240 BOEING SERVICE BULLETIN 737-53A1301 ALERTALERT ### Page 22 GroupVariable Number 14PS907 - PS924 15PS925 - PS941 14PS956 - PS957 16PS961 - PS963 16PS971 - PS978 9PT001 - PT011 23PT012 - PT014 24PT015 9PT021 - PT028 23PT029 - PT031 11PT041 - PT063 23PT064 9PT101 - PT105 11PT121 - PT125 23PT126 - PT131 24PT132 - PT134 25PT135 - PT138 11PT146 - PT148 9PT161 - PT170 10PT181 - PT187 23PT188 11PT211 - PT220 10PT295 11PT301 - PT306 23PT307 - PT309 11PT331 - PT360 11PT381 - PT399 11PT401 - PT438 11PT501 - PT512 23PT513 - PT517 11PT561 - PT565 9PT581 - PT584 23PT585 BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: September 03, 2009 737-53A1301Revision 1: June 07, 2010 22 of 240 BOEING SERVICE BULLETIN 737-53A1301 ALERTALERT ### Page 23 GroupVariable Number 24PT586 11PT611 - PT621 9PT641 - PT642 23PT643 - PT644 11PT651 - PT655 23PT656 11PT671 - PT672 24PT681 - PT685 8PT701 - PT703 23PT716 - PT717 23PT721 24PT722 25PT723 - PT725 23PT801 - PT834 23PT851 - PT853 25PT854 23PT871 - PT876 24PT877 - PT880 25PT881 - PT886 24PT901 - PT911 25PT912 - PT930 23PT971 - PT973 24PT981 - PT983 25PT984 - PT985 24PT996 12PU001 - PU025 24PU301 25PU311 - PU313 7PV001 - PV055 7PV201 - PV203 19PV204 - PV205 20PV206 - PV209 19PV226 BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: September 03, 2009 737-53A1301Revision 1: June 07, 2010 23 of 240 BOEING SERVICE BULLETIN 737-53A1301 ALERTALERT ### Page 24 GroupVariable Number 20PV227 - PV228 21PV229 6PV231 - PV237 7PV271 - PV272 7PV281 - PV283 19PV284 - PV285 20PV286 - PV287 19PV296 19PV301 20PV302 20PV351 22PV356 - PV357 7PW001 - PW054 7PW061 - PW068 7PW072 19PW086 - PW088 7PW091 - PW094 7PW101 - PW102 7PW106 7PW111 - PW120 7PW156 - PW157 7PW161 - PW167 21PW168 22PW169 - PW171 7PW201 - PW244 19PW245 - PW251 20PW252 7PW261 19PW262 22PW263 - PW264 7PW265 - PW268 19PW271 - PW275 20PW276 BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: September 03, 2009 737-53A1301Revision 1: June 07, 2010 24 of 240 BOEING SERVICE BULLETIN 737-53A1301 ALERTALERT ### Page 25 GroupVariable Number 7PW278 7PW281 19PW282 - PW292 7PW293 7PW296 7PW301 - PW327 19PW401 - PW403 20PW404 22PW405 - PW408 19PW411 - PW413 20PW414 - PW415 21PW416 22PW417 - PW418 21PW421 - PW422 22PW423 - PW424 22PW431 - PW435 22PW441 - PW450 7PW461 6PW462 7PW463 - PW467 7PW501 - PW504 7PW511 - PW515 6PW516 - PW520 19PW521 - PW522 19PW524 - PW525 6PW526 19PW527 - PW530 7PW531 - PW546 19PW547 - PW550 7PW556 - PW557 7PW561 - PW564 6PW571 - PW576 6PW591 - PW596 BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: September 03, 2009 737-53A1301Revision 1: June 07, 2010 25 of 240 BOEING SERVICE BULLETIN 737-53A1301 ALERTALERT ### Page 26 GroupVariable Number 7PW611 - PW620 19PW621 - PW622 6PW631 - PW634 19PW635 - PW637 7PW661 - PW662 7PW681 - PW683 7PW701 6PW702 7PW711 - PW717 7PW741 - PW742 7PW761 6PW771 20PW831 20PW851 - PW852 21PW853 22PW854 - PW856 26PX071 26PX701 26PY001 - PY008 26PY021 1PY022 26PY031 1PY036 - PY037 1PY046 - PY048 1PY051 - PY053 1PY056 - PY057 1PY101 - PY103 1PY111 - PY113 1PY131 - PY135 1PY141 - PY143 1PY151 - PY154 1PY156 - PY157 1PY161 - PY162 BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: September 03, 2009 737-53A1301Revision 1: June 07, 2010 26 of 240 BOEING SERVICE BULLETIN 737-53A1301 ALERTALERT ### Page 27 GroupVariable Number 1PY166 1PY191 1PY201 1PY221 - PY222 1PY231 1PY241 - PY244 1PY270 - PY275 1PY281 1PY286 26PY301 - PY304 26PY321 - PY323 26PY341 - PY346 26PY361 - PY362 26PY381 1PY401 1PY409 - PY411 1PY421 - PY422 1PY441 1PY451 1PY461 - PY463 1PY591 - PY595 1PY611 - PY612 1PY621 1PY631 1PY651 1PY671 - PY672 1PY721 1PY741 2. Spares Affected None. B. Concurrent Requirements None. BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: September 03, 2009 737-53A1301Revision 1: June 07, 2010 27 of 240 BOEING SERVICE BULLETIN 737-53A1301 ALERTALERT ### Page 28 C. Reason Accomplishment of the inspections in this service bulletin will make sure that fuselage crown skin cracks at horizontal chem-mill steps at specified locations between Body Stations 259.5 and Body Stations 1016 and between stringers S-10L and S-10R are found and repaired. All airplanes listed in this service bulletin require inspection. This action is necessary to find and repair fatigue cracking of the skin panel at the specified chem-mill step locations which could result in rapid decompression of the airplane. Boeing received a report from an operator of a hole in the fuselage skin common to stringer S-1 and S-2L, between STA 827 and STA 847. The crack started along the chem-mill edge along stringer S-1. The airplane skin in the area had 20 inch tear strap bays. The airplane diverted to an alternate airport due to cabin depressurization and subsequent deployment of the oxygen masks. The airplane had accumulated 42,569 total flight cycles. Airplanes with 10 inch tear strap bays are also susceptible to cracks at this location. The cause of cracking is under investigation. After the release of the original issue of this service bulletin additional crack indications have been reported. Boeing Service Related Problem (SRP) 737-SRP-53-0346 is related to this service bulletin. Service History Reports of cracks in crown skinsFlight HoursFlight CyclesStringerStation 3 reports, above the forward entry door, on air- planes with 10 inch tear strap bays, in Groups 1-12 of this service bulletin. 66132-7467063725-698452-LSTA 342-348 One report at MLS antenna provision, on air- planes with 20 inch tear strap bays, in Groups 13-25 of this service bulletin. 51899435561-LSTA 470 3 reports at ADF antenna provision, on airplanes with 20 inch tear strap bays, in Groups 13-25 of this service bulletin. 51964-5330443690-448151-LSTA 510 One report at HF antenna provision, on air- planes with 10 inch tear strap bays, in Groups 1-12 of this service bulletin. 49627447572-LSTA 581 Two reports at ELT antenna provision, on air- planes with 20 inch tear strap bays, in Groups 13-25 of this service bulletin. 50883-5276242569-443932-L and 2-RSTA827 8 reports, above the aft galley door, on airplanes with 10 inch tear strap bays, in Groups 1-12 of this service bulletin. 66989-7573563998-711295-RSTA 947-1006 5 reports, above the aft galley door, on airplanes with 20 inch tear strap bays, in Groups 13-25 of this service bulletin. 41259-4928536187-414095-RSTA 947-1006 Revision 1 is sent to add additional crown skin inspection areas and 737-200/-200C/-300/-400/-500 airplanes. Changes to this Service Bulletin include: BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: September 03, 2009 737-53A1301Revision 1: June 07, 2010 28 of 240 BOEING SERVICE BULLETIN 737-53A1301 ALERTALERT ### Page 29 1. Summary BACKGROUND: Paragraphs 1 and 2 revised and service history table added 2. Summary ACTION: Paragraphs 1 and 2 revised and 3 added 3. Summary EFFECTIVITY: 737-200/-200C airplanes and all 737-300/-400/-500 airplanes without ELT antenna provisions added 4. Summary COMPLIANCE: AD added 5. Summary MANPOWER: Added groups 3 through 25 and revised the Total Task Hours and Elapsed Hours in groups 1 and 2 6. Summary ILLUSTRATION: Updated 7. Section 1.A.1. Effectivity: Group Configuration table revised and groups 3 through 26 added 8. Section 1.C. Reason: Paragraphs 1 and 2 revised and service history table added 9. Section 1.D. Description: Paragraphs 1 and 2 revised and Affected Maintenance Zones tables revised 10. Section 1.E. Compliance: Table 1, revised: Tables 2, 3 and 4 added 11. Section 1.F. Approval: Alternate Means of Compliance (AMOC) paragraph added 12. Section 1.G. Manpower: Revised tables 1 and 2 and added tables 3 through 25 13. Section 1.J. References: Added 1.J.1.c., 1.J.1.d. and revised the table in 1.J.3 14. Section 3.A. GENERAL INFORMATION: Added NOTEs 4, 7 and 8 15. Section 3.B. WORK INSTRUCTIONS: revised to add steps 1 through 26 16. FIGURES: Figures 1 and 2 revised and Figures 3 through 25 added 17. APPENDIX: Added Appendix A. Revision 1: More work is necessary on airplanes that have accomplished the initial release of this Service Bulletin. D. Description Get external access to the specified locations. Do an external Detailed Inspection and one of the external Non Destructive Inspection (NDI) specified in the compliance section of this service bulletin for cracking in the fuselage skin along the chem-mill steps at the specified locations. The NDI that can be used are Medium Frequency Eddy Current (MFEC), Magneto Optical Imaging (MOI), C-Scan or Ultrasonic Phased Array (UTPA). If any crack is found, contact Boeing for repair instructions and do the repair. If no cracking is found, do the repeat inspection in accordance with this service bulletin. BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: September 03, 2009 737-53A1301Revision 1: June 07, 2010 29 of 240 BOEING SERVICE BULLETIN 737-53A1301 ALERTALERT ### Page 30 Group 26: Before further flight, operators with Group 26 airplanes must contact Boeing to obtain engineering and accomplishment instructions for this inspection, and then do the instructions. The work in this service bulletin is done in the maintenance zone(s) given below. Group 1, 26: Affected Maintenance Zones ZoneModel 1-7, 1-8737-200, 737-200C Group 2-5, 13-18: Affected Maintenance Zones ZoneModel 108737-300 Group 6-7, 19-22: Affected Maintenance Zones ZoneModel 108737-400 Group 8-12, 23-25: Affected Maintenance Zones ZoneModel 108737-500 E. Compliance Federal Aviation Administration (FAA) Airworthiness Directive AD 2010-01-09 is related to this service bulletin. Group 26: Before further flight, operators with Group 26 airplanes must contact Boeing to obtain engineering and accomplishment instructions for this inspection, and then do the instructions. BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: September 03, 2009 737-53A1301Revision 1: June 07, 2010 30 of 240 BOEING SERVICE BULLETIN 737-53A1301 ALERTALERT ### Page 31 Group 2, 8, 10: Table 1: Fuselage Skin Inspections at ELT Antenna Skin Provision Common to Aircraft with 10 inch tear strap bays at Stringers S-1 and S-2R, STA 827-STA 847 Repeat Interval (Not to Exceed) Compliance Time (Whichever Occurs Later) ActionCondition 1800 flight cycles for an Option 1 in- spection. (b) Within 1800 flight cycles af- ter the original issue date on the service bul- letin. Before 35,000 total flight cy- cles. Option 1: Do a Detailed Inspection (DI) and one of the following external Non Destructive Inspec- tion (NDI): Medium Fre- quency Eddy Current (MFEC) or Magneto Opti- cal Imaging (MOI) or C- Scan Inspection for cracking in the fuselage skin at the chem-mill steps at S-1 and S-2R between STA 827 and STA 847 in accordance with the applicable Ac- complishment Instruc- tions in 3.B.1 through 3.B.25. (a) All Airplanes with an ELT Antenna Skin Provision - If the inspection procedure is being changed from Op- tion 2 to Option 1, the first Option 1 inspection must be done within 2400 flight cycles after the Option 2 inspec- tion. Then the re- maining Option 1 inspections that follow must be done within 1800 flight cycle repeat intervals. - OR - Within 1800 flight cycles af- ter doing inspec- tions in accor- dance with the original issue of this service bul- letin. - OR -- OROption 2: Do a Detailed Inspection (DI) and an external Non Destructive Inspection (NDI): Ultrason- ic Phased Array Inspec- tion (UTPA) for cracking in the fuselage skin at the chem-mill steps at S-1 and S-2R between STA 827 and STA 847 in ac- cordance with the applica- ble Accomplishment In- structions in 3.B.1 through 3.B.25 (a) - 2400 flight cycles for an Option 2 in- spection. (b) - If the inspection procedure is being changed from Op- tion 1 to Option 2 the first two Option 2 inspections must be done within 1800 flight cycle repeat intervals. Then the Option 2 inspections that follow must be done within 2400 flight cycle repeat intervals. - - - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: September 03, 2009 737-53A1301Revision 1: June 07, 2010 31 of 240 BOEING SERVICE BULLETIN 737-53A1301 ALERTALERT ### Page 32 Group 2, 8, 10: Table 1: Fuselage Skin Inspections at ELT Antenna Skin Provision Common to Aircraft with 10 inch tear strap bays at Stringers S-1 and S-2R, STA 827-STA 847 Repeat Interval (Not to Exceed) Compliance Time (Whichever Occurs Later) ActionCondition Any crack found in the fuselage skin -Before further flight.Contact Boeing for repair instructions and do the repair. Do not cut out the damage prior to receiving repair instructions from Boeing. It is likely that the cutout will be requested for further metallurgical analysis so the cutout will likely be larger than a typical repair. (a) It is not necessary to inspect the chem-mill steps under an existing external repair doubler provided all of the following apply: 1. The repair was installed after the release date of Revision 0 of this service bulletin. 2. The repair was approved by the FAA or by a Boeing company authorized representative who was authorized by the FAA to make such findings 3. The repair extends a minimum of three rows of fasteners on each side of the chem-mill line in the circumferential direction. (b) Accomplishment of the repair approved by a Boeing company authorized representative terminates the requirements to do the repeat inspections under the repair area only. BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: September 03, 2009 737-53A1301Revision 1: June 07, 2010 32 of 240 BOEING SERVICE BULLETIN 737-53A1301 ALERTALERT ### Page 33 Group 1-12: Table 2: Fuselage Skin Inspections Common to Aircraft with 10 inch Tear Strap Bays at New Locations Added as Given in Revision 1 of this service bulletin Repeat Interval (Not to Exceed) Compliance Time (Whichever Occurs Later) ActionCondition 1800 flight cycles for an Option 1 in- spection. (b) Within 1800 flight cycles af- ter the Revision 1 date on the service bulletin. Before 35,000 total flight cy- cles. Option 1: Do a Detailed Inspection (DI) and one of the following external Non Destructive Inspec- tion (NDI): Medium Fre- quency Eddy Current (MFEC) or Magneto Opti- cal Imaging (MOI) or C- Scan Inspection for cracking in the fuselage skin at the chem-mill steps at the specified loca- tions other than at S-1 and S-2R between STA 827 and STA 847 in ac- cordance with the applica- ble Accomplishment In- structions in 3.B.1 through 3.B.25. (a) All Airplanes - If the inspection procedure is being changed from Op- tion 2 to Option 1, the first Option 1 inspection must be done within 2400 flight cycles after the Option 2 inspec- tion. Then the re- maining Option 1 inspections that follow must be done within 1800 flight cycle repeat intervals.- -OR OR- -Option 2: Do a Detailed Inspection (DI) and an external Non Destructive Inspection (NDI): Ultrason- ic Phased Array Inspec- tion (UTPA) for cracking in the fuselage skin at the chem-mill steps at the specified locations other than at S-1 and S-2R be- tween STA 827 and STA 847 in accordance with the applicable Accom- plishment Instructions in 3.B.1 through 3.B.25. (a) 2400 flight cycles for an Option 2 in- spection. (b) - If the inspection procedure is being changed from Op- tion 1 to Option 2, the first two Option 2 inspections must be done within 1800 flight cycle repeat intervals. Then the Option 2 inspections that follow must be done within 2400 flight cycle repeat intervals. - - - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: September 03, 2009 737-53A1301Revision 1: June 07, 2010 33 of 240 BOEING SERVICE BULLETIN 737-53A1301 ALERTALERT ### Page 34 Group 1-12: Table 2: Fuselage Skin Inspections Common to Aircraft with 10 inch Tear Strap Bays at New Locations Added as Given in Revision 1 of this service bulletin Repeat Interval (Not to Exceed) Compliance Time (Whichever Occurs Later) ActionCondition Any crack found in the fuselage skin -Before further flight.Contact Boeing for repair instructions and do the repair. Do not cut out the damage prior to receiving repair instructions from Boeing. It is likely that the cutout will be requested for further metallurgical analysis so the cutout will likely be larger than a typical repair. (a) It is not necessary to inspect the chem-mill steps under an existing external repair doubler provided all of the following apply: 1. The repair was installed after the release date of Revision 1 of this service bulletin. 2. The repair was approved by the FAA or by a Boeing company authorized representative who was authorized by the FAA to make such findings 3. The repair extends a minimum of three rows of fasteners on each side of the chem-mill line in the circumferential direction. (b) Accomplishment of the repair approved by a Boeing company authorized representative terminates the requirements to do the repeat inspections under the repair area only. BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: September 03, 2009 737-53A1301Revision 1: June 07, 2010 34 of 240 BOEING SERVICE BULLETIN 737-53A1301 ALERTALERT ### Page 35 Group 13-18, 21-25: Table 3: Fuselage Skin Inspections at ELT Antenna Skin Provision Common to Aircraft with 20 inch tear strap bays at Stringers S-1 and S-2R, STA 827-STA 847 Repeat Interval (Not to Exceed) Compliance Time (Whichever Occurs Later) ActionCondition 500 flight cycles for an Option 1 inspec- tion. (b) Within 500 flight cycles after the original issue date on the ser- vice bulletin. Before 33,000 total flight cy- cles. Option 1: Do a Detailed Inspection (DI) and one of the following external Non Destructive Inspec- tion (NDI): Medium Fre- quency Eddy Current (MFEC) or Magneto Opti- cal Imaging (MOI) or C- Scan Inspection for cracking in the fuselage skin at the chem-mill steps at S-1 and S-2R between STA 827 and STA 847 in accordance with the applicable Ac- complishment Instruc- tions in 3.B.1 through 3.B.25. (a) All Airplanes with an ELT Antenna Skin Provision - If the inspection procedure is being changed from Op- tion 2 to Option 1, the first Option 1 inspection must be done within 1000 flight cycles after the Option 2 inspec- tion. Then the re- maining Option 1 inspections that follow must be done within 500 flight cycle repeat intervals. - OR - Within 500 flight cycles after do- ing inspections in accordance with the original issue of this ser- vice bulletin. - OR -- OROption 2: Do a Detailed Inspection (DI) and an external Non Destructive Inspection (NDI): Ultrason- ic Phased Array Inspec- tion (UTPA) for cracking in the fuselage skin at the chem-mill steps at S-1 and S-2R between STA 827 and STA 847 in ac- cordance with the applica- ble Accomplishment In- structions in 3.B.1 through 3.B.25 (a) - 1000 flight cycles for an Option 2 in- spection. (b) - If the inspection procedure is being changed from Op- tion 1 to Option 2, the first two Option 2 inspections must be done within 500 flight cycle repeat intervals. Then the Option 2 inspec- tions that follow must be done with- in 1000 flight cycle repeat intervals. - - - - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: September 03, 2009 737-53A1301Revision 1: June 07, 2010 35 of 240 BOEING SERVICE BULLETIN 737-53A1301 ALERTALERT ### Page 36 Group 13-18, 21-25: Table 3: Fuselage Skin Inspections at ELT Antenna Skin Provision Common to Aircraft with 20 inch tear strap bays at Stringers S-1 and S-2R, STA 827-STA 847 Repeat Interval (Not to Exceed) Compliance Time (Whichever Occurs Later) ActionCondition Any crack found in the fuselage skin -Before further flight.Contact Boeing for repair instructions and do the repair. Do not cut out the damage prior to receiving repair instructions from Boeing. It is likely that the cutout will be requested for further metallurgical analysis so the cutout will likely be larger than a typical repair. (a) It is not necessary to inspect the chem-mill steps under an existing external repair doubler provided all of the following apply: 1. The repair was installed after the release date of Revision 0 of this service bulletin. 2. The repair was approved by the FAA or by a Boeing company authorized representative who was authorized by the FAA to make such findings 3. The repair extends a minimum of three rows of fasteners on each side of the chem-mill line in the circumferential direction. (b) Accomplishment of the repair approved by a Boeing company authorized representative terminates the requirements to do the repeat inspections under the repair area only. BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: September 03, 2009 737-53A1301Revision 1: June 07, 2010 36 of 240 BOEING SERVICE BULLETIN 737-53A1301 ALERTALERT ### Page 37 Group 13-25: Table 4: Fuselage Skin Inspections Common to Aircraft with 20 inch Tear Strap Bays at New Locations Added as Given in Revision 1 to this service bulletin Repeat Interval (Not to Exceed) Compliance Time (Whichever Occurs Later) ActionCondition 500 flight cycles for an Option 1 inspec- tion. (b) Within 500 flight cycles after the Revision 1 date on the service bulletin. Before 33,000 total flight cy- cles. Option 1: Do a Detailed Inspection (DI) and one of the following external Non Destructive Inspec- tion (NDI): Medium Fre- quency Eddy Current (MFEC) or Magneto Opti- cal Imaging (MOI) or C- Scan Inspection for cracking in the fuselage skin at the chem-mill steps at the specified loca- tions other than at S-1 and S-2R between STA 827 and STA 847 in ac- cordance with the applica- ble Accomplishment In- structions in 3.B.1 through 3.B.25. (a) All Airplanes - If the inspection procedure is being changed from Op- tion 2 to Option 1, the first Option 1 inspection must be done within 1000 flight cycles after the Option 2 inspec- tion. Then the re- maining Option 1 inspections that follow must be done within 500 flight cycle repeat intervals.- -OR OR- -Option 2: Do a Detailed Inspection (DI) and an external Non Destructive Inspection (NDI): Ultrason- ic Phased Array Inspec- tion (UTPA) for cracking in the fuselage skin at the chem-mill steps at the specified locations other than at S-1 and S-2R be- tween STA 827 and STA 847 in accordance with the applicable Accom- plishment Instructions in 3.B.1 through 3.B.25 (a) 1000 flight cycles for an Option 2 in- spection. (b) - If the inspection procedure is being changed from Op- tion 1 to Option 2, the first two Option 2 inspections must be done within 500 flight cycle repeat intervals. Then the Option 2 inspec- tions that follow must be done with- in 1000 flight cycle repeat intervals. - - - - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: September 03, 2009 737-53A1301Revision 1: June 07, 2010 37 of 240 BOEING SERVICE BULLETIN 737-53A1301 ALERTALERT ### Page 38 Group 13-25: Table 4: Fuselage Skin Inspections Common to Aircraft with 20 inch Tear Strap Bays at New Locations Added as Given in Revision 1 to this service bulletin Repeat Interval (Not to Exceed) Compliance Time (Whichever Occurs Later) ActionCondition Any crack found in the fuselage skin -Before further flight.Contact Boeing for repair instructions and do the repair. Do not cut out the damage prior to receiving repair instructions from Boeing. It is likely that the cutout will be requested for further metallurgical analysis so the cutout will likely be larger than a typical repair. (a) It is not necessary to inspect the chem-mill steps under an existing external repair doubler provided all of the following apply: 1. The repair was installed after the release date of Revision 1 of this service bulletin. 2. The repair was approved by the FAA or by a Boeing company authorized representative who was authorized by the FAA to make such findings 3. The repair extends a minimum of three rows of fasteners on each side of the chem-mill line in the circumferential direction. (b) Accomplishment of the repair approved by a Boeing company authorized representative terminates the requirements to do the repeat inspections under the repair area only. F. Approval This service bulletin was examined by the Federal Aviation Administration (FAA). The changes specified in this service bulletin comply with the applicable regulations and are FAA approved, as well as European Aviation Safety Agency (EASA)/Joint Aviation Authorities (JAA) approved for all EASA/JAA approved airplanes listed in the service bulletin effectivity. This service bulletin and its approval were based on the airplane in its original Boeing delivery configuration or as modified by other approved Boeing changes. If an airplane has a non-Boeing modification or repair that affects a component or system also affected by this service bulletin, the operator is responsible for obtaining appropriate regulatory agency approval before incorporating this service bulletin. BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: September 03, 2009 737-53A1301Revision 1: June 07, 2010 38 of 240 BOEING SERVICE BULLETIN 737-53A1301 ALERTALERT ### Page 39 In addition, the Manager of the FAA Seattle Aircraft Certification Office (ACO) approves the inspections with the corresponding compliance times specified in Tables 1 through 4, under paragraph 1.E., "Compliance," of Service Bulletin 737-53A1301 Revision 1 as an AMOC to the inspections with the corresponding compliance times specified in Table 1 under paragraph 1.E., "Compliance," of Service Bulletin 737-53A1301, dated September 3, 2009, required by paragraph (g) of AD 2010-01-09. When this service bulletin specifies contacting Boeing for repair instructions, the repair instructions must be approved by the FAA is accordance with the AD. All provisions of AD 2010-01-09 that are not specifically referenced in the above statement remain fully applicable and must be complied with. G. Manpower The table below shows an estimate of the task hours necessary to do this inspection for each airplane. This estimate is for direct labor only, done by an experienced crew. Adjust the estimate with operator task hour data if necessary. The estimate does not include lost time. These are some examples of lost time:  Time to adjust to the workplace  Time to schedule the work  Time to inspect the work  Time to cure the materials  Time to make the parts  Time to find the tools. Group 1: Elapsed HoursTask HoursNumber of PersonsTask 0.250.251Get Access 0.501.002Figure 1 0.250.251Close Access 1.001.50TOTAL FOR EACH AIRPLANE Group 2: Elapsed HoursTask HoursNumber of PersonsTask 0.750.751Get Access 2.755.502Figure 2 0.750.751Close Access 4.257.00TOTAL FOR EACH AIRPLANE Group 3: Elapsed HoursTask HoursNumber of PersonsTask 0.750.751Get Access 2.755.502Figure 3 0.750.751Close Access BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: September 03, 2009 737-53A1301Revision 1: June 07, 2010 39 of 240 BOEING SERVICE BULLETIN 737-53A1301 ALERTALERT ### Page 40 Group 3: Elapsed HoursTask HoursNumber of PersonsTask 4.257.00TOTAL FOR EACH AIRPLANE Group 4: Elapsed HoursTask HoursNumber of PersonsTask 0.750.751Get Access 2.004.002Figure 4 0.750.751Close Access 3.505.50TOTAL FOR EACH AIRPLANE Group 5: Elapsed HoursTask HoursNumber of PersonsTask 0.750.751Get Access 1.753.502Figure 5 0.750.751Close Access 3.255.00TOTAL FOR EACH AIRPLANE Group 6: Elapsed HoursTask HoursNumber of PersonsTask 0.750.751Get Access 2.505.002Figure 6 0.750.751Close Access 4.006.50TOTAL FOR EACH AIRPLANE Group 7: Elapsed HoursTask HoursNumber of PersonsTask 0.750.751Get Access 2.004.002Figure 7 0.750.751Close Access 3.505.50TOTAL FOR EACH AIRPLANE BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: September 03, 2009 737-53A1301Revision 1: June 07, 2010 40 of 240 BOEING SERVICE BULLETIN 737-53A1301 ALERTALERT ### Page 41 Group 8: Elapsed HoursTask HoursNumber of PersonsTask 0.750.751Get Access 2.755.502Figure 8 0.750.751Close Access 4.257.00TOTAL FOR EACH AIRPLANE Group 9: Elapsed HoursTask HoursNumber of PersonsTask 0.750.751Get Access 2.755.502Figure 9 0.750.751Close Access 4.257.00TOTAL FOR EACH AIRPLANE Group 10: Elapsed HoursTask HoursNumber of PersonsTask 0.750.751Get Access 3.507.002Figure 10 0.750.751Close Access 5.008.50TOTAL FOR EACH AIRPLANE Group 11: Elapsed HoursTask HoursNumber of PersonsTask 0.750.751Get Access 2.254.502Figure 11 0.750.751Close Access 3.756.00TOTAL FOR EACH AIRPLANE Group 12: Elapsed HoursTask HoursNumber of PersonsTask 0.750.751Get Access 1.753.502Figure 12 0.750.751Close Access 3.255.00TOTAL FOR EACH AIRPLANE BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: September 03, 2009 737-53A1301Revision 1: June 07, 2010 41 of 240 BOEING SERVICE BULLETIN 737-53A1301 ALERTALERT ### Page 42 Group 13: Elapsed HoursTask HoursNumber of PersonsTask 1.251.251Get Access 4.5018.002Figure 13 1.251.251Close Access 7.0020.50TOTAL FOR EACH AIRPLANE Group 14: Elapsed HoursTask HoursNumber of PersonsTask 1.251.251Get Access 6.75527.002Figure 14 1.251.251Close Access 9.2529.50TOTAL FOR EACH AIRPLANE Group 15: Elapsed HoursTask HoursNumber of PersonsTask 1.251.251Get Access 6.7527.002Figure 15 1.251.251Close Access 9.2529.50TOTAL FOR EACH AIRPLANE Group 16: Elapsed HoursTask HoursNumber of PersonsTask 1.251.251Get Access 6.5026.002Figure 16 1.251.251Close Access 9.0028.50TOTAL FOR EACH AIRPLANE Group 17: Elapsed HoursTask HoursNumber of PersonsTask 0.750.751Get Access 3.0012.002Figure 17 0.750.751Close Access 4.5013.50TOTAL FOR EACH AIRPLANE BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: September 03, 2009 737-53A1301Revision 1: June 07, 2010 42 of 240 BOEING SERVICE BULLETIN 737-53A1301 ALERTALERT ### Page 43 Group 18: Elapsed HoursTask HoursNumber of PersonsTask 0.750.751Get Access 4.2517.002Figure 18 0.750.751Close Access 5.7518.50TOTAL FOR EACH AIRPLANE Group 19: Elapsed HoursTask HoursNumber of PersonsTask 1.251.251Get Access 5.5022.002Figure 19 1.251.251Close Access 8.0025.50TOTAL FOR EACH AIRPLANE Group 20: Elapsed HoursTask HoursNumber of PersonsTask 1.251.251Get Access 5.5022.002Figure 20 1.251.251Close Access 8.0024.50TOTAL FOR EACH AIRPLANE Group 21: Elapsed HoursTask HoursNumber of PersonsTask 1.251.251Get Access 6.0024.002Figure 21 1.251.251Close Access 8.5026.50TOTAL FOR EACH AIRPLANE Group 22: Elapsed HoursTask HoursNumber of PersonsTask 1.251.251Get Access 5.7523.002Figure 22 1.251.251Close Access 8.2525.50TOTAL FOR EACH AIRPLANE BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: September 03, 2009 737-53A1301Revision 1: June 07, 2010 43 of 240 BOEING SERVICE BULLETIN 737-53A1301 ALERTALERT ### Page 44 Group 23: Elapsed HoursTask HoursNumber of PersonsTask 1.251.251Get Access 5.7523.002Figure 23 1.251.251Close Access 8.2525.50TOTAL FOR EACH AIRPLANE Group 24: Elapsed HoursTask HoursNumber of PersonsTask 1.251.251Get Access 5.7523.002Figure 24 1.251.251Close Access 8.2525.50TOTAL FOR EACH AIRPLANE Group 25: Elapsed HoursTask HoursNumber of PersonsTask 1.251.251Get Access 5.7523.002Figure 25 1.251.251Close Access 8.2525.50TOTAL FOR EACH AIRPLANE H. Weight and Balance Changes None. I. Electrical Load Data Not changed. J. References 1. Existing Data a. Boeing Service Letter 737-SL-51-042 b. Federal Aviation Administration (FAA) Airworthiness Directive 2010-01-09, AD 2010-01-09 c. 737 Non-Destructive Testing (NDT) Manual Part 4, 53-30-07, Part 6, 53-30-09, Part 6, 53-30-18, Part 6, 53-30-19, Part 6, 53-30-25 BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: September 03, 2009 737-53A1301Revision 1: June 07, 2010 44 of 240 BOEING SERVICE BULLETIN 737-53A1301 ALERTALERT ### Page 45 2. Data supplied with this Service Bulletin None. 3. Installation Drawings Used in the Preparation of this Service Bulletin TitleDrawing Number SKIN INSTL - STA 727 TO STA 908, S-10L TO S-10R65C35772 SKIN PANEL INSTL - S-10L TO S-10R, STA 727 TO STA 101665-45772 SKIN INSTL - STA 727 TO STA 908, S-10L TO S-10R65C35772 SKIN PANEL INSTL - S-10L TO S-10R, STA 727 TO STA 101665-45772 SKIN AND STRINGER INSTL - SECTION 4165-45800 SKIN INSTL - STA 259.5 TO STA 360.0, S-4L TO S-4R65C27758 SKIN AND STRINGER INSTL - FORWARD ENTRY AND GALLEY DOORS 65C34778 SKIN PANEL INSTALLATION - S-10L TO S-10R, STA 360 - STA 540 65-45765 SKIN INSTL - S-10L TO S-10R, STA 360 TO STA 54065C35765 SKIN PANEL INSTL - S-10L TO S-10R, STA 540 TO STA 72765-45770 SKIN INSTL - S-10L TO S-10R, STA 540 TO STA 72765C35770 SKIN PANEL INSTL-AFT GALLEY DOOR, STA 908 - STA 1016, S-4R TO S-25R 65-45778 SKIN INSTL - AFT GALLEY DOOR, STA 908 TO STA 1016, S-4R TO S-25R 65C27756 SKIN PANEL INSTL - AFT GALLEY DOOR, STA 908 - STA 1016, S-4R TO S-25R 65C35778 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 but no new DTIs are necessary. BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: September 03, 2009 737-53A1301Revision 1: June 07, 2010 45 of 240 BOEING SERVICE BULLETIN 737-53A1301 ALERTALERT ### Page 46 L. Interchangeability and Intermixability of Parts Accomplishment of this service bulletin does not affect interchangeability or intermixability of parts. BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: September 03, 2009 737-53A1301Revision 1: June 07, 2010 46 of 240 BOEING SERVICE BULLETIN 737-53A1301 ALERTALERT ### Page 47 2. MATERIAL INFORMATION A. Material - Price and Availability None. B. Industry Support Information At the time of release of this service bulletin, warranty remedies have not been determined. A subsequent revision or Information Notice will address the warranty remedies available, if any. 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. BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: September 03, 2009 737-53A1301Revision 1: June 07, 2010 47 of 240 BOEING SERVICE BULLETIN 737-53A1301 ALERTALERT ### Page 48 BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: September 03, 2009 737-53A1301Revision 1: June 07, 2010 48 of 240 BOEING SERVICE BULLETIN 737-53A1301 ALERTALERT BLANK PAGE ### Page 49 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. The instructions identified in Paragraph 3.B., Work Instructions, and the Figure(s) give the recommended sequence of steps. The sequence of steps to do this service bulletin can be changed. 2. Manual titles are referred to by acronyms. Refer to Paragraph 1.J., References, for definition of the acronyms. 3. Obey all of the warnings and cautions given in the specified manual sections. 4. A Detailed Inspection is defined as: An intensive examination of a specific item, installation, or assembly to detect damage, failure, or irregularity. Available lighting is normally supplemented with a direct source of good lighting at an intensity deemed appropriate. Inspection aids such as mirrors, magnifying lenses, etc. may be necessary. Surface cleaning and elaborate access procedures may be required. 5. A Special Detailed Inspection is defined as: An intensive examination of a specific item, installation or assembly to detect damage, failure or irregularity. The examination is likely to make extensive use of specialized Inspection Techniques and/or equipment. Intricate cleaning and substantial access or disassembly procedure may be required. 6. These work instructions refer to procedures included in other Boeing documents. When the words "refer to" are used and the operator has an accepted alternative procedure, the accepted alternative procedure can be used. When the words "in accordance with" are included in the instruction, the procedure in the Boeing document must be used. 7. 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. 8. Refer to APPENDIX A for NDI inspection detail. B. WORK INSTRUCTIONS 1. Group 1: a. Initial and Repeat Inspection BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: September 03, 2009 737-53A1301Revision 1: June 07, 2010 49 of 240 BOEING SERVICE BULLETIN 737-53A1301 ALERTALERT ### Page 50 (1) Get external access to the areas at the specified locations as given in FIGURE 1. (2) Do a Detailed Inspection and a Special Detailed Inspection (an external NDI Inspection using one of the following methods - Medium Frequency Eddy Current (MFEC), Magneto Optical Imaging (MOI), C-Scan, or Ultrasonic Phased Array(UTPA)), for cracking in the fuselage skin along the chem-mill steps at the specified locations in accordance with FIGURE 1. (3) If any crack is found, contact Boeing for repair instructions and do the repair. (4) If no crack is found do the repeat inspection in accordance with Paragraph 1.E., Compliance. b. Put the airplane back to a serviceable condition. 2. Group 2: a. Initial and Repeat Inspection (1) Get external access to the areas at the specified locations as given in FIGURE 2. (2) Do a Detailed Inspection and a Special Detailed Inspection (an external NDI Inspection using one of the following methods - Medium Frequency Eddy Current (MFEC), Magneto Optical Imaging (MOI), C-Scan, or Ultrasonic Phased Array(UTPA)), for cracking in the fuselage skin along the chem-mill steps at the specified locations in accordance with FIGURE 2. (3) If any crack is found, contact Boeing for repair instructions and do the repair. (4) If no crack is found do the repeat inspection in accordance with Paragraph 1.E., Compliance. b. Put the airplane back to a serviceable condition. 3. Group 3: a. Initial and Repeat Inspection (1) Get external access to the areas at the specified locations as given in FIGURE 3. (2) Do a Detailed Inspection and a Special Detailed Inspection (an external NDI Inspection using one of the following methods - Medium Frequency Eddy Current (MFEC), Magneto Optical Imaging (MOI), C-Scan, or Ultrasonic Phased Array(UTPA)), for cracking in the fuselage skin along the chem-mill steps at the specified locations in accordance with FIGURE 3. (3) If any crack is found, contact Boeing for repair instructions and do the repair. (4) If no crack is found do the repeat inspection in accordance with Paragraph 1.E., Compliance. b. Put the airplane back to a serviceable condition. BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: September 03, 2009 737-53A1301Revision 1: June 07, 2010 50 of 240 BOEING SERVICE BULLETIN 737-53A1301 ALERTALERT ### Page 51 4. Group 4: a. Initial and Repeat Inspection (1) Get external access to the areas at the specified locations as given in FIGURE 4. (2) Do a Detailed Inspection and a Special Detailed Inspection (an external NDI Inspection using one of the following methods - Medium Frequency Eddy Current (MFEC), Magneto Optical Imaging (MOI), C-Scan, or Ultrasonic Phased Array(UTPA)), for cracking in the fuselage skin along the chem-mill steps at the specified locations in accordance with FIGURE 4. (3) If any crack is found, contact Boeing for repair instructions and do the repair. (4) If no crack is found do the repeat inspection in accordance with Paragraph 1.E., Compliance. b. Put the airplane back to a serviceable condition. 5. Group 5: a. Initial and Repeat Inspection (1) Get external access to the areas at the specified locations as given in FIGURE 5. (2) Do a Detailed Inspection and a Special Detailed Inspection (an external NDI Inspection using one of the following methods - Medium Frequency Eddy Current (MFEC), Magneto Optical Imaging (MOI), C-Scan, or Ultrasonic Phased Array(UTPA)), for cracking in the fuselage skin along the chem-mill steps at the specified locations in accordance with FIGURE 5. (3) If any crack is found, contact Boeing for repair instructions and do the repair. (4) If no crack is found do the repeat inspection in accordance with Paragraph 1.E., Compliance. b. Put the airplane back to a serviceable condition. 6. Group 6: a. Initial and Repeat Inspection BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: September 03, 2009 737-53A1301Revision 1: June 07, 2010 51 of 240 BOEING SERVICE BULLETIN 737-53A1301 ALERTALERT ### Page 52 (1) Get external access to the areas at the specified locations as given in FIGURE 6. (2) Do a Detailed Inspection and a Special Detailed Inspection (an external NDI Inspection using one of the following methods - Medium Frequency Eddy Current (MFEC), Magneto Optical Imaging (MOI), C-Scan, or Ultrasonic Phased Array(UTPA)), for cracking in the fuselage skin along the chem-mill steps at the specified locations in accordance with FIGURE 6. (3) If any crack is found, contact Boeing for repair instructions and do the repair. (4) If no crack is found do the repeat inspection in accordance with Paragraph 1.E., Compliance. b. Put the airplane back to a serviceable condition. 7. Group 7: a. Initial and Repeat Inspection (1) Get external access to the areas at the specified locations as given in FIGURE 7. (2) Do a Detailed Inspection and a Special Detailed Inspection (an external NDI Inspection using one of the following methods - Medium Frequency Eddy Current (MFEC), Magneto Optical Imaging (MOI), C-Scan, or Ultrasonic Phased Array(UTPA)), for cracking in the fuselage skin along the chem-mill steps at the specified locations in accordance with FIGURE 7. (3) If any crack is found, contact Boeing for repair instructions and do the repair. (4) If no crack is found do the repeat inspection in accordance with Paragraph 1.E., Compliance. b. Put the airplane back to a serviceable condition. 8. Group 8: a. Initial and Repeat Inspection (1) Get external access to the areas at the specified locations as given in FIGURE 8. (2) Do a Detailed Inspection and a Special Detailed Inspection (an external NDI Inspection using one of the following methods - Medium Frequency Eddy Current (MFEC), Magneto Optical Imaging (MOI), C-Scan, or Ultrasonic Phased Array(UTPA)), for cracking in the fuselage skin along the chem-mill steps at the specified locations in accordance with FIGURE 8. (3) If any crack is found, contact Boeing for repair instructions and do the repair. (4) If no crack is found do the repeat inspection in accordance with Paragraph 1.E., Compliance. b. Put the airplane back to a serviceable condition. BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: September 03, 2009 737-53A1301Revision 1: June 07, 2010 52 of 240 BOEING SERVICE BULLETIN 737-53A1301 ALERTALERT ### Page 53 9. Group 9: a. Initial and Repeat Inspection (1) Get external access to the areas at the specified locations as given in FIGURE 9. (2) Do a Detailed Inspection and a Special Detailed Inspection (an external NDI Inspection using one of the following methods - Medium Frequency Eddy Current (MFEC), Magneto Optical Imaging (MOI), C-Scan, or Ultrasonic Phased Array(UTPA)), for cracking in the fuselage skin along the chem-mill steps at the specified locations in accordance with FIGURE 9. (3) If any crack is found, contact Boeing for repair instructions and do the repair. (4) If no crack is found do the repeat inspection in accordance with Paragraph 1.E., Compliance. b. Put the airplane back to a serviceable condition. 10. Group 10: a. Initial and Repeat Inspection (1) Get external access to the areas at the specified locations as given in FIGURE 10. (2) Do a Detailed Inspection and a Special Detailed Inspection (an external NDI Inspection using one of the following methods - Medium Frequency Eddy Current (MFEC), Magneto Optical Imaging (MOI), C-Scan, or Ultrasonic Phased Array(UTPA)), for cracking in the fuselage skin along the chem-mill steps at the specified locations in accordance with FIGURE 10. (3) If any crack is found, contact Boeing for repair instructions and do the repair. (4) If no crack is found do the repeat inspection in accordance with Paragraph 1.E., Compliance. b. Put the airplane back to a serviceable condition. 11. Group 11: a. Initial and Repeat Inspection BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: September 03, 2009 737-53A1301Revision 1: June 07, 2010 53 of 240 BOEING SERVICE BULLETIN 737-53A1301 ALERTALERT ### Page 54 (1) Get external access to the areas at the specified locations as given in FIGURE 11. (2) Do a Detailed Inspection and a Special Detailed Inspection (an external NDI Inspection using one of the following methods - Medium Frequency Eddy Current (MFEC), Magneto Optical Imaging (MOI), C-Scan, or Ultrasonic Phased Array(UTPA)), for cracking in the fuselage skin along the chem-mill steps at the specified locations in accordance with FIGURE 11. (3) If any crack is found, contact Boeing for repair instructions and do the repair. (4) If no crack is found do the repeat inspection in accordance with Paragraph 1.E., Compliance. b. Put the airplane back to a serviceable condition. 12. Group 12: a. Initial and Repeat Inspection (1) Get external access to the areas at the specified locations as given in FIGURE 12. (2) Do a Detailed Inspection and a Special Detailed Inspection (an external NDI Inspection using one of the following methods - Medium Frequency Eddy Current (MFEC), Magneto Optical Imaging (MOI), C-Scan, or Ultrasonic Phased Array(UTPA)), for cracking in the fuselage skin along the chem-mill steps at the specified locations in accordance with FIGURE 12. (3) If any crack is found, contact Boeing for repair instructions and do the repair. (4) If no crack is found do the repeat inspection in accordance with Paragraph 1.E., Compliance. b. Put the airplane back to a serviceable condition. 13. Group 13: a. Initial and Repeat Inspection (1) Get external access to the areas at the specified locations as given in FIGURE 13. (2) Do a Detailed Inspection and a Special Detailed Inspection (an external NDI Inspection using one of the following methods - Medium Frequency Eddy Current (MFEC), Magneto Optical Imaging (MOI), C-Scan, or Ultrasonic Phased Array(UTPA)), for cracking in the fuselage skin along the chem-mill steps at the specified locations in accordance with FIGURE 13. (3) If any crack is found, contact Boeing for repair instructions and do the repair. (4) If no crack is found do the repeat inspection in accordance with Paragraph 1.E., Compliance. b. Put the airplane back to a serviceable condition. BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: September 03, 2009 737-53A1301Revision 1: June 07, 2010 54 of 240 BOEING SERVICE BULLETIN 737-53A1301 ALERTALERT ### Page 55 14. Group 14: a. Initial and Repeat Inspection (1) Get external access to the areas at the specified locations as given in FIGURE 14. (2) Do a Detailed Inspection and a Special Detailed Inspection (an external NDI Inspection using one of the following methods - Medium Frequency Eddy Current (MFEC), Magneto Optical Imaging (MOI), C-Scan, or Ultrasonic Phased Array(UTPA)), for cracking in the fuselage skin along the chem-mill steps at the specified locations in accordance with FIGURE 14. (3) If any crack is found, contact Boeing for repair instructions and do the repair. (4) If no crack is found do the repeat inspection in accordance with Paragraph 1.E., Compliance. b. Put the airplane back to a serviceable condition. 15. Group 15: a. Initial and Repeat Inspection (1) Get external access to the areas at the specified locations as given in FIGURE 15. (2) Do a Detailed Inspection and a Special Detailed Inspection (an external NDI Inspection using one of the following methods - Medium Frequency Eddy Current (MFEC), Magneto Optical Imaging (MOI), C-Scan, or Ultrasonic Phased Array(UTPA)), for cracking in the fuselage skin along the chem-mill steps at the specified locations in accordance with FIGURE 15. (3) If any crack is found, contact Boeing for repair instructions and do the repair. (4) If no crack is found do the repeat inspection in accordance with Paragraph 1.E., Compliance. b. Put the airplane back to a serviceable condition. 16. Group 16: a. Initial and Repeat Inspection BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: September 03, 2009 737-53A1301Revision 1: June 07, 2010 55 of 240 BOEING SERVICE BULLETIN 737-53A1301 ALERTALERT ### Page 56 (1) Get external access to the areas at the specified locations as given in FIGURE 16. (2) Do a Detailed Inspection and a Special Detailed Inspection (an external NDI Inspection using one of the following methods - Medium Frequency Eddy Current (MFEC), Magneto Optical Imaging (MOI), C-Scan, or Ultrasonic Phased Array(UTPA)), for cracking in the fuselage skin along the chem-mill steps at the specified locations in accordance with FIGURE 16. (3) If any crack is found, contact Boeing for repair instructions and do the repair. (4) If no crack is found do the repeat inspection in accordance with Paragraph 1.E., Compliance. b. Put the airplane back to a serviceable condition. 17. Group 17: a. Initial and Repeat Inspection (1) Get external access to the areas at the specified locations as given in FIGURE 17. (2) Do a Detailed Inspection and a Special Detailed Inspection (an external NDI Inspection using one of the following methods - Medium Frequency Eddy Current (MFEC), Magneto Optical Imaging (MOI), C-Scan, or Ultrasonic Phased Array(UTPA)), for cracking in the fuselage skin along the chem-mill steps at the specified locations in accordance with FIGURE 17. (3) If any crack is found, contact Boeing for repair instructions and do the repair. (4) If no crack is found do the repeat inspection in accordance with Paragraph 1.E., Compliance. b. Put the airplane back to a serviceable condition. 18. Group 18: a. Initial and Repeat Inspection (1) Get external access to the areas at the specified locations as given in FIGURE 18. (2) Do a Detailed Inspection and a Special Detailed Inspection (an external NDI Inspection using one of the following methods - Medium Frequency Eddy Current (MFEC), Magneto Optical Imaging (MOI), C-Scan, or Ultrasonic Phased Array(UTPA)), for cracking in the fuselage skin along the chem-mill steps at the specified locations in accordance with FIGURE 18. (3) If any crack is found, contact Boeing for repair instructions and do the repair. (4) If no crack is found do the repeat inspection in accordance with Paragraph 1.E., Compliance. b. Put the airplane back to a serviceable condition. BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: September 03, 2009 737-53A1301Revision 1: June 07, 2010 56 of 240 BOEING SERVICE BULLETIN 737-53A1301 ALERTALERT ### Page 57 19. Group 19: a. Initial and Repeat Inspection (1) Get external access to the areas at the specified locations as given in FIGURE 19. (2) Do a Detailed Inspection and a Special Detailed Inspection (an external NDI Inspection using one of the following methods - Medium Frequency Eddy Current (MFEC), Magneto Optical Imaging (MOI), C-Scan, or Ultrasonic Phased Array(UTPA)), for cracking in the fuselage skin along the chem-mill steps at the specified locations in accordance with FIGURE 19. (3) If any crack is found, contact Boeing for repair instructions and do the repair. (4) If no crack is found do the repeat inspection in accordance with Paragraph 1.E., Compliance. b. Put the airplane back to a serviceable condition. 20. Group 20: a. Initial and Repeat Inspection (1) Get external access to the areas at the specified locations as given in FIGURE 20. (2) Do a Detailed Inspection and a Special Detailed Inspection (an external NDI Inspection using one of the following methods - Medium Frequency Eddy Current (MFEC), Magneto Optical Imaging (MOI), C-Scan, or Ultrasonic Phased Array(UTPA)), for cracking in the fuselage skin along the chem-mill steps at the specified locations in accordance with FIGURE 20. (3) If any crack is found, contact Boeing for repair instructions and do the repair. (4) If no crack is found do the repeat inspection in accordance with Paragraph 1.E., Compliance. b. Put the airplane back to a serviceable condition. 21. Group 21: a. Initial and Repeat Inspection BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: September 03, 2009 737-53A1301Revision 1: June 07, 2010 57 of 240 BOEING SERVICE BULLETIN 737-53A1301 ALERTALERT ### Page 58 (1) Get external access to the areas at the specified locations as given in FIGURE 21. (2) Do a Detailed Inspection and a Special Detailed Inspection (an external NDI Inspection using one of the following methods - Medium Frequency Eddy Current (MFEC), Magneto Optical Imaging (MOI), C-Scan, or Ultrasonic Phased Array(UTPA)), for cracking in the fuselage skin along the chem-mill steps at the specified locations in accordance with FIGURE 21. (3) If any crack is found, contact Boeing for repair instructions and do the repair. (4) If no crack is found do the repeat inspection in accordance with Paragraph 1.E., Compliance. b. Put the airplane back to a serviceable condition. 22. Group 22: a. Initial and Repeat Inspection (1) Get external access to the areas at the specified locations as given in FIGURE 22. (2) Do a Detailed Inspection and a Special Detailed Inspection (an external NDI Inspection using one of the following methods - Medium Frequency Eddy Current (MFEC), Magneto Optical Imaging (MOI), C-Scan, or Ultrasonic Phased Array(UTPA)), for cracking in the fuselage skin along the chem-mill steps at the specified locations in accordance with FIGURE 22. (3) If any crack is found, contact Boeing for repair instructions and do the repair. (4) If no crack is found do the repeat inspection in accordance with Paragraph 1.E., Compliance. b. Put the airplane back to a serviceable condition. 23. Group 23: a. Initial and Repeat Inspection (1) Get external access to the areas at the specified locations as given in FIGURE 23. (2) Do a Detailed Inspection and a Special Detailed Inspection (an external NDI Inspection using one of the following methods - Medium Frequency Eddy Current (MFEC), Magneto Optical Imaging (MOI), C-Scan, or Ultrasonic Phased Array(UTPA)), for cracking in the fuselage skin along the chem-mill steps at the specified locations in accordance with FIGURE 23. (3) If any crack is found, contact Boeing for repair instructions and do the repair. (4) If no crack is found do the repeat inspection in accordance with Paragraph 1.E., Compliance. b. Put the airplane back to a serviceable condition. BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: September 03, 2009 737-53A1301Revision 1: June 07, 2010 58 of 240 BOEING SERVICE BULLETIN 737-53A1301 ALERTALERT ### Page 59 24. Group 24: a. Initial and Repeat Inspection (1) Get external access to the areas at the specified locations as given in FIGURE 24. (2) Do a Detailed Inspection and a Special Detailed Inspection (an external NDI Inspection using one of the following methods - Medium Frequency Eddy Current (MFEC), Magneto Optical Imaging (MOI), C-Scan, or Ultrasonic Phased Array(UTPA)), for cracking in the fuselage skin along the chem-mill steps at the specified locations in accordance with FIGURE 24. (3) If any crack is found, contact Boeing for repair instructions and do the repair. (4) If no crack is found do the repeat inspection in accordance with Paragraph 1.E., Compliance. b. Put the airplane back to a serviceable condition. 25. Group 25: a. Initial and Repeat Inspection (1) Get external access to the areas at the specified locations as given in FIGURE 25. (2) Do a Detailed Inspection and a Special Detailed Inspection (an external NDI Inspection using one of the following methods - Medium Frequency Eddy Current (MFEC), Magneto Optical Imaging (MOI), C-Scan, or Ultrasonic Phased Array(UTPA)), for cracking in the fuselage skin along the chem-mill steps at the specified locations in accordance with FIGURE 25. (3) If any crack is found, contact Boeing for repair instructions and do the repair. (4) If no crack is found do the repeat inspection in accordance with Paragraph 1.E., Compliance. b. Put the airplane back to a serviceable condition. 26. Group 26: Operators with Group 26 airplanes must contact Boeing to obtain engineering and accomplishment instructions for this inspection, and then do the instructions. BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: September 03, 2009 737-53A1301Revision 1: June 07, 2010 59 of 240 BOEING SERVICE BULLETIN 737-53A1301 ALERTALERT ### Page 60 (OCR) BOEING SERVICE BULLETIN 737-53A1301 ALERT ALERT This Figure applies only to: Group 1. 259.5 STA STA 360 STA 540 STA 727 STA 908 1016 SIA S-26R BL 0 S-19R S-25R S-24R S-20R S-19R 0000000000p000 • 0000000000000000 S-14R S-14R S-10R S-10R S-4R S-4R S-4L S-4L S-10L S-14L S-10L 00000г Joo0000 0 ood 0000000000do S-14L S-19L S-24L S-20L S-19L S-25L BL O S-26L 737-200 737-200C ALMOST THE SAME SKIN DOUBLER STA STA STA STA STA 559 578 597 616 639 S-2L - S-4L - FWD NDI INSPECTION AREA 1929421 FIGURE 1: FUSELAGE - SKIN AT AREAS WITH DOUBLER PROVISIONS FOR GROUP 1 AIRPLANES - NON DESTRUCTIVE INSPECTION (SHEET 1 OF 2) Original Issue: September 03, 2009 Revision 1 June 07, 2010 BOEING PROPRIETARY - 737-53A1301 Copyright © Unpublished Work - See page 1 for details. 60 of 240 The text continues at https://openairdocs.org/service-documents/boeing/737-53a1301/file/b45327fbb15c.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.