# Boeing Alert Service Bulletin 737-57A1329: No revision named - Rights: © The Boeing Company. Filed by the FAA in regulations.gov docket FAA-2017-0526; AD 2017-24-05 incorporates this document by reference. Not covered by OpenAirDocs’ CC0 dedication. - Document: [Boeing Alert Service Bulletin 737-57A1329](https://openairdocs.org/service-documents/boeing/737-57a1329.md) - Title as filed: SB 737-57A1329 - Pages: 56 - PDF: https://openairdocs.org/files/sha256/1a/9f/1a9f35b5282e40354536be8ff616fed8c88d22e81cdbdae92fc221630f04604d - Page: https://openairdocs.org/service-documents/boeing/737-57a1329/file/1a9f35b5282e ## 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: 737-57A1329 Original Issue: January 16, 2017 ATA System: 5730 SUBJECT: WINGS - Plates/Skin - Upper Aft Skin at Rear Spar from Wing Buttock Line 159 to 220 - Inspection Export of this technology is controlled under the United States Export Administration Regulations (EAR) (15 CFR 300-774). An export license may be required before it is used for development, production or use by foreign persons from specific countries. The controller of this data has the individual responsibility to abide by all export laws. 9E991ECCN: BOEING PROPRIETARY, CONFIDENTIAL AND/OR TRADE SECRET Copyright © 2017 Boeing. Unpublished Work. All Rights Reserved. Treatment of this document and its content is governed by contract with Boeing. Rights to use this document are licensed on a per aircraft basis and such rights may not be transferable. For more information, contact The Boeing Company. Boeing, the Boeing signature, the Boeing symbol, 707, 717, 727, 737, 747, 757, 767, 777, 787, Dreamliner, BBJ, DC-8, DC-9, DC-10, KC-10, KC-46, KDC-10, MD-10, MD-11, MD-80, MD-88, MD-90, P-8, Poseidon and Boeing liveries are all trademarks owned by The Boeing Company; and no trademark license is granted in connection with this document unless provided in writing by Boeing. Original Issue: January 16, 2017 737-57A1329 1 of 56 3.0 ### Page 2 Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: January 16, 2017 737-57A1329 2 of 56 BOEING SERVICE BULLETIN 737-57A1329 ALERTALERT BLANK PAGE ### Page 3 Table of Contents Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 1. PLANNING INFORMATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9 A. Effectivity . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9 1. Airplanes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9 2. Spares Affected . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21 B. Concurrent Requirements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21 C. Reason . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21 D. Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22 E. Compliance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23 F. Approval . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28 G. Manpower . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28 H. Weight and Balance Changes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29 I. Electrical Load Data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29 J. References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29 1. Existing Data: . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29 2. Data Supplied with this Service Bulletin: . . . . . . . . . . . . . . . . . . . . . . . . . . . 30 3. Installation Drawings Used in the Preparation of this Service Bulletin: . . . . . . . . . . . 30 K. Publications Affected . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30 L. Interchangeability and Intermixability of Parts . . . . . . . . . . . . . . . . . . . . . . . . . . . 30 M. Software Accomplishment Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30 2. MATERIAL INFORMATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31 A. Material - Price and Availability . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31 B. Industry Support Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31 C. Parts Necessary for Each Airplane . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31 1. Kits/Parts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31 2. Parts and Materials Supplied by the Operator . . . . . . . . . . . . . . . . . . . . . . . . 31 3. Parts Modified and Reidentified . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31 4. Parts Removed and Not Replaced . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31 D. Parts Necessary to Change Spares . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31 E. Special Tooling - Price and Availability . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31 F. Special Tooling Necessary to do this Service Bulletin . . . . . . . . . . . . . . . . . . . . . . . 31 3. ACCOMPLISHMENT INSTRUCTIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33 A. GENERAL INFORMATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33 B. WORK INSTRUCTIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35 FIGURE 1: LEFT WING UPPER AFT SKIN - WBL 159 TO WBL 220 IN AREAS WITHOUT AN EXTERNAL REPAIR - INSPECTION [Group 2-3] . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37 FIGURE 2: LEFT WING UPPER AFT SKIN - WBL 159 TO WBL 220 IN AREAS WITH AN EXTERNAL REPAIR - INSPECTION [Group 2-3, Configuration 2] . . . . . . . . . . . . . . . . . . . . 40 FIGURE 3: RIGHT WING UPPER AFT SKIN - WBL 159 TO WBL 220 IN AREAS WITHOUT AN EXTERNAL REPAIR - INSPECTION [Group 2-3] . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 43 FIGURE 4: RIGHT WING UPPER AFT SKIN - WBL 159 TO WBL 220 IN AREAS WITH AN EXTERNAL REPAIR - INSPECTION [Group 2-3, Configuration 2] . . . . . . . . . . . . . . . . . . . . 46 APPENDIX A: LOGIC DIAGRAM FOR PARAGRAPH 1.E. COMPLIANCE: TABLE 1: SURFACE HIGH FREQUENCY EDDY CURRENT (HFEC) INSPECTION OF THE UPPER AFT SKIN ON THE LEFT AND RIGHT WING FROM WING BUTTOCK LINE (WBL) 159 TO WBL 220 [Group 2] . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 49 Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: January 16, 2017 737-57A1329 3 of 56 BOEING SERVICE BULLETIN 737-57A1329 ALERTALERT ### Page 4 APPENDIX B: LOGIC DIAGRAM FOR PARAGRAPH 1.E. COMPLIANCE: TABLE 2: SURFACE HIGH FREQUENCY EDDY CURRENT (HFEC), LOW FREQUENCY EDDY CURRENT (LFEC) & DETAILED INSPECTION OF THE UPPER AFT SKIN AND EXTERNAL REPAIR ON THE LEFT OR RIGHT WING FROM WING BUTTOCK LINE (WBL) 159 TO WBL 220 [Group 2, Configuration 2] . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 51 APPENDIX C: LOGIC DIAGRAM FOR PARAGRAPH 1.E. COMPLIANCE: TABLE 3: SURFACE HIGH FREQUENCY EDDY CURRENT (HFEC) INSPECTION OF THE UPPER AFT SKIN ON THE LEFT AND RIGHT WING FROM WING BUTTOCK LINE (WBL) 159 TO WBL 220 [Group 3] . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 53 APPENDIX D: LOGIC DIAGRAM FOR PARAGRAPH 1.E. COMPLIANCE: TABLE 4: SURFACE HIGH FREQUENCY EDDY CURRENT (HFEC), LOW FREQUENCY EDDY CURRENT (LFEC) & DETAILED INSPECTION OF THE UPPER AFT SKIN AND EXTERNAL REPAIR ON THE LEFT OR RIGHT WING FROM WING BUTTOCK LINE (WBL) 159 TO WBL 220 [Group 3, Configuration 2] . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 55 Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: January 16, 2017 737-57A1329 4 of 56 BOEING SERVICE BULLETIN 737-57A1329 ALERTALERT ### Page 5 Commercial Airplanes 737 Service Bulletin ALERT SummaryNumber: 737-57A1329Original Issue: January 16, 2017 ATA System: 5730 SUBJECT: WINGS - Plates/Skin - Upper Aft Skin at Rear Spar from Wing Buttock Line 159 to 220 - Inspection THIS DOCUMENT IS SENT TO THE OPERATORS OF RECORD OF THE AIRPLANES SHOWN IN PARAGRAPH 1.A., EFFECTIVITY. IF AN AIRPLANE HAS BEEN LEASED OR SOLD, SEND THIS DOCUMENT TO THE NEW OPERATOR. IF APPLICABLE SPARES HAVE BEEN SOLD, SEND THIS DOCUMENT TO THE NEW OWNER. CONCURRENT REQUIREMENTS None. BACKGROUND Accomplishment of this service bulletin will make sure that cracks are found in the upper aft skin (inspar upper skin) of the left and right wing at the rear spar from Wing Buttock Line (WBL) 159 to WBL 220. Undetected cracks in the upper aft skin may lead to the inability of a principal structural element to sustain limit load which could adversely affect the structural integrity of the airplane. During a visual inspection, a 737-400 operator found a crack in the left upper aft skin originating from a fastener hole common to the upper aft skin and strap aft of the rear spar at WBL 187. The airplane had 49,461 flight hours and 47,718 flight cycles. A total of 73 cases of the upper aft skin cracks have been reported to Boeing between 1993 and November 2015, of which 24 cases were reported in 2015. The cracks measured from 0.02 inches to 3.0 inches long. The table below contains information about crack lengths, flight cycles and number of cracks found between WBL 170 and WBL 200. Reported crack data for 737-200/200C/300/400/500 airplanes between 1993 and 2015 Number of cracks foundFlight CyclesCrack Length 2628,000 - 69,000Less than 1 inch 3326,000 - 73,000Between 1 inch and 2 inches 1430,000 - 70,000More than 2 inches Cracks between WBL 159 and WBL 200 were also found during open hole High Frequency Eddy Current (HFEC) inspection as part of the wing rear spar upper chord splice repair in relation to SB 737-57-1318 original issue and SB 737-57A1326 original issue. Most large cracks were reported at WBL 171, 183, 187 and 200 at the end fasteners common to the straps attaching the wing trailing edge to the wing upper aft skin. Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: January 16, 2017 737-57A1329 5 of 56 ### Page 6 Cracks between WBL 159 and WBL 220 originated from fastener holes common to the upper aft skin and strap aft of the rear spar upper chord. Analysis shows that ground loads introduce a high tension stress in the wing trailing edge skin outboard of the main landing gear beam attachment and high bearing load transfer occurs at the end fasteners of the straps attaching the trailing edge skin to the upper aft skin. This combination of ground loads and bending loads at the skin/strap joint lead to cracks originating from fastener holes which can then lead to fatigue. Failure occurs with the combination of skin and rear spar upper chord cracking. There has been no report of the upper chord cracking to date at this location. Boeing has determined that the existing inspection programs are not sufficient to find such cracks before they could grow to a critical length. This service bulletin provides instructions for inspection of the upper aft skin aft of the rear spar for any crack from WBL 159 to WBL 220 to make sure they are found and repaired before they reach a critical length Boeing Service Related Problem (SRP) 737-SRP-57-0302 is related to this service bulletin. Boeing Fleet Team Digest (FTD) 737 FTD 57-15002 is related to this service bulletin. This table is provided to operators for planning purposes only. Refer to the applicable sections for more information. ReferenceAffectedPlanning Data Paragraph 1.A.2., Spares AffectedNoSpares Affected Paragraph 1.E., Compliance and Paragraph 1.F., Approval YesAD Related Paragraph 1.H., Weight and Balance ChangesNoWeight and Balance Change Paragraph 1.I., Electrical Load DataNoElectrical Load Changed Paragraph 1.K., Publications AffectedNoPublications Affected Paragraph 1.K., Publications AffectedNoAirplane Flight Operations Affected (Flight Crew Operations Manual and/or FAA Approved Air- plane Flight Manual) Paragraph 2.C.1., Kits/PartsNoKits/Parts Required Paragraph 2.C.2., Parts and Materials Supplied by the Operator NoOperator Supplied Parts/Material Paragraph 2.F., Special Tooling Necessary to do this Service Bulletin NoSpecial Tooling Required ACTION Group 1: Boeing endorses the new FAA rules related to Limit of Validity (LOV) and recommends immediate and permanent removal from service of any airplanes upon reaching the LOV, whether or not it is operated under FAA jurisdiction. As such, Boeing no longer provides maintenance instructions for airplanes that have accumulated flight cycles beyond the LOV. 737 Classic airplanes line numbers 1-291 have accumulated flight cycles beyond the LOV of the maintenance program. 14 CFR 121.1115 and 129.115 prohibit operation of an airplane beyond its LOV. Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: January 16, 2017 737-57A1329 6 of 56 BOEING SERVICE BULLETIN 737-57A1329 ALERTALERT ### Page 7 Group 2-3: Do the work that follows on the left and right wing from Wing Buttock Line (WBL) 159 to WBL 220: Group 2-3: 1. Deactivate the trailing edge flap system. 2. In areas without an external repair, do a surface High Frequency Eddy Current (HFEC) inspection for any crack in the upper aft skin. If any crack is found contact The Boeing Company for repair instructions and do the repair. Repeat inspections in unrepaired areas. If no crack is found repeat the inspections. 3. In areas with an external repair, do surface HFEC, Low Frequency Eddy Current (LFEC) and detailed inspections for any crack. If any crack is found contact The Boeing Company for repair instructions and do the repair. If no crack is found repeat the inspections. 4. Activate the trailing edge flap system. EFFECTIVITY All 737-100/200/200C/300/400/500 Airplane(s). Refer to Paragraph 1.A.1., Airplanes, for the list of affected airplanes. COMPLIANCE The Federal Aviation Administration (FAA) will possibly release an Airworthiness Directive related to this service bulletin. The Airworthiness Directive will make the compliance tasks and times given in this service bulletin mandatory. Refer to Paragraph 1.E., Compliance. INDUSTRY SUPPORT INFORMATION Boeing warranty remedies are not available for the inspection given in this service bulletin. MANPOWER Refer to Paragraph 1.G., Manpower. MATERIAL INFORMATION None. Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: January 16, 2017 737-57A1329 7 of 56 BOEING SERVICE BULLETIN 737-57A1329 ALERTALERT ### Page 8 (OCR) BOEING SERVICE BULLETIN 737-57A1329 ALERT ALERT N AREAS WITHOUT AN EXTERNAL REPAIR, DO A SURFACE HFEC INSPECTION FOR ANY CRACK IN THE UPPER AFT SKIN. IN AREAS WITH AN EXTERNAL REPAIR, DO SURFACE HFEC, LFEC AND DETAILED LEFT WING INSPECTIONS FOR ANY CRACK IF ANY CRACK IS FOUND, CONTACT THE BOEING COMPANY FOR REPAIR INSTRUCTIONS AND DO WBL THE REPAIR. REPEAT INSPECTIONS IN 159 UNREPAIRED AREAS IF NO CRACK IS FOUND, REPEAT INSPECTIONS. _S-6 WBL _S-5 187 _ S-4 WBL 200 WBL 220 + - /++ + + (+ ++++ +++ +++++++++ NBD LEFT WING SHOWN, RIGHT WING OPPOSITE 2536190 Original Issue: January 16, 2017 PROPRIETARY - Copyright © Unpublished Export Controlled ECCN: 9E991 - BOEING 737-57A1329 Work - See page 1 for details. 8 of 56 ### Page 9 Commercial Airplanes 737 Service Bulletin ALERT Number: 737-57A1329 Original Issue: January 16, 2017 ATA System: 5730 SUBJECT: WINGS - Plates/Skin - Upper Aft Skin at Rear Spar from Wing Buttock Line 159 to 220 - Inspection THIS DOCUMENT IS SENT TO THE OPERATORS OF RECORD OF THE AIRPLANES SHOWN IN PARAGRAPH 1.A., EFFECTIVITY. IF AN AIRPLANE HAS BEEN LEASED OR SOLD, SEND THIS DOCUMENT TO THE NEW OPERATOR. IF APPLICABLE SPARES HAVE BEEN SOLD, SEND THIS DOCUMENT TO THE NEW OWNER. 1. PLANNING INFORMATION A. Effectivity 1. Airplanes This service bulletin is applicable to all 737-100/200/200C/300/400/500 Airplanes, line numbers 1-3132 in 3 Groups. The Variable Numbers and Group Information for the applicable airplanes is given below. Refer to Service Bulletin Index D6-19567 Part 3 for Airplane Variable Number, Line Number, and Serial Number data. The term "external repair" is defined as any combination of a repair doubler and repair tripler. The term "inspection area' is defined as the upper aft skin area of the wing from Wing Buttock Line (WBL) 159 to WBL 220 on the left and right wing on an airplane. DESCRIPTIONCONFIGURATIONGROUP 737-100/200/200C airplanes, line numbers 1-291-1 737-300/400/500 airplanes, line numbers 1001-3132-2 Airplanes with no external repair in the inspection area1 Airplanes with an external repair in the inspection area2 Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: January 16, 2017 737-57A1329 9 of 56 ### Page 10 DESCRIPTIONCONFIGURATIONGROUP 737-200/200C airplanes, line numbers 292-1585-3 Airplanes with no external repair in the inspection area1 Airplanes with an external repair in the inspection area2 Airplane Models: 737-100, 737-200, 737-200C, 737-300, 737-400, 737-500 GroupVariable Number 1PA001 - PA022 1PA099 1PA231 - PA232 1PC001 - PC005 1PG001 - PG075 1PG199 1PG201 - PG230 1PG251 - PG255 1PG271 - PG279 1PG301 - PG314 1PG331 - PG332 1PG351 - PG356 1PG375 1PG401 - PG403 1PG431 - PG442 1PG471 - PG475 1PG501 - PG505 1PG571 - PG583 3PG584 - PG586 1PG621 - PG630 1PG651 - PG652 1PG701 - PG705 3PH001 3PH011 - PH013 Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: January 16, 2017 737-57A1329 10 of 56 BOEING SERVICE BULLETIN 737-57A1329 ALERTALERT ### Page 11 GroupVariable Number 3PH021 - PH024 1PH701 - PH715 1PH731 - PH732 1PH741 - PH742 3PH743 1PJ001 - PJ002 3PJ003 - PJ009 1PJ031 - PJ032 1PJ071 - PJ072 1PJ101 - PJ104 3PJ105 - PJ119 3PJ201 - PJ219 2PJ301 - PJ302 2PJ551 - PJ561 2PJ601 - PJ615 2PJ811 2PJ816 - PJ817 3PK026 - PK029 3PK041 - PK053 3PK061 - PK070 3PK081 - PK082 3PK091 - PK099 3PK101 - PK103 3PK111 - PK120 3PK141 - PK146 3PK201 - PK204 3PK211 - PK223 3PK231 - PK241 3PK251 - PK258 3PK271 - PK274 3PK281 - PK289 3PK291 3PK301 - PK318 Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: January 16, 2017 737-57A1329 11 of 56 BOEING SERVICE BULLETIN 737-57A1329 ALERTALERT ### Page 12 GroupVariable Number 3PK341 3PK351 - PK361 3PK391 3PK431 - PK433 3PK451 - PK452 3PK461 - PK469 3PK495 3PK501 - PK504 3PK511 - PK515 3PK519 3PK521 - PK528 3PK541 - PK565 3PK581 3PK591 - PK599 3PK601 - PK617 3PK621 - PK637 3PK641 - PK642 3PK661 - PK666 3PK671 - PK681 3PK691 - PK697 3PK711 - PK716 3PK731 - PK765 3PK771 - PK779 3PK801 - PK804 3PK819 - PK827 3PK830 3PK861 - PK863 3PK871 - PK874 3PK881 - PK884 3PK901 - PK938 3PK971 - PK974 3PL001 - PL028 3PL061 Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: January 16, 2017 737-57A1329 12 of 56 BOEING SERVICE BULLETIN 737-57A1329 ALERTALERT ### Page 13 GroupVariable Number 3PL081 3PL101 - PL113 3PL151 3PL171 - PL172 3PL201 - PL203 3PL221 3PL401 - PL417 3PL421 3PL441 3PL451 - PL456 3PL471 3PL491 3PL501 - PL506 3PL551 - PL562 3PL581 3PL601 - PL603 3PL611 3PL621 - PL626 3PL631 - PL632 1PL711 - PL712 1PL716 3PL717 - PL747 3PL756 3PL758 3PL761 - PL770 3PL781 - PL788 3PL793 1PL801 - PL803 3PM001 - PM006 3PM016 - PM017 3PM021 - PM023 3PM051 - PM066 3PM101 - PM119 Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: January 16, 2017 737-57A1329 13 of 56 BOEING SERVICE BULLETIN 737-57A1329 ALERTALERT ### Page 14 GroupVariable Number 3PM141 - PM142 3PM171 3PM181 3PM251 - PM255 3PM281 - PM283 2PM381 - PM399 2PM401 - PM417 2PM541 - PM564 3PN001 - PN002 3PN021 - PN043 3PN081 - PN086 3PN101 - PN117 3PN131 - PN163 3PN401 - PN420 3PN431 - PN433 3PN451 - PN456 3PN471 - PN474 3PN481 3PN491 - PN493 3PN501 - PN502 3PN511 - PN512 3PN521 2PP001 - PP054 2PP101 - PP169 2PP181 - PP199 2PP201 - PP205 2PP221 2PP231 - PP243 2PP281 - PP286 2PP301 - PP305 2PP351 - PP353 2PP376 - PP384 2PP391 - PP393 Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: January 16, 2017 737-57A1329 14 of 56 BOEING SERVICE BULLETIN 737-57A1329 ALERTALERT ### Page 15 GroupVariable Number 2PP401 - PP440 2PP471 - PP475 2PP501 - PP522 2PP631 - PP634 2PP651 - PP652 2PP671 - PP699 2PP701 - PP733 2PP771 - PP779 2PP801 - PP808 2PP821 - PP827 2PP831 - PP848 2PP851 - PP852 2PP861 - PP877 2PP891 - PP899 2PP901 - PP936 2PP946 - PP948 2PP951 - PP952 2PP961 - PP967 2PP981 - PP991 2PP993 2PQ001 - PQ016 2PQ026 - PQ041 2PQ051 - PQ092 2PQ101 - PQ199 2PQ201 - PQ202 2PQ221 - PQ237 2PQ241 - PQ243 2PQ251 - PQ267 2PQ281 - PQ299 2PQ301 - PQ307 2PQ331 - PQ332 2PQ341 - PQ348 2PQ361 - PQ373 Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: January 16, 2017 737-57A1329 15 of 56 BOEING SERVICE BULLETIN 737-57A1329 ALERTALERT ### Page 16 GroupVariable Number 2PQ391 - PQ395 2PQ401 - PQ418 2PQ421 2PQ431 - PQ438 2PQ447 - PQ448 2PQ451 2PQ454 2PQ471 - PQ475 2PQ479 - PQ481 2PQ486 - PQ487 2PQ491 - PQ493 2PQ771 - PQ772 2PQ791 - PQ793 2PQ801 - PQ805 2PQ931 - PQ935 2PQ951 2PQ971 - PQ997 2PR001 - PR017 2PR021 - PR034 2PR041 - PR045 2PR061 - PR072 2PR077 - PR082 2PR091 - PR092 2PR096 2PR101 2PR121 - PR122 2PR131 - PR132 2PR141 - PR143 2PR161 - PR172 2PR181 2PS601 - PS631 2PS636 - PS638 2PS641 - PS644 Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: January 16, 2017 737-57A1329 16 of 56 BOEING SERVICE BULLETIN 737-57A1329 ALERTALERT ### Page 17 GroupVariable Number 2PS651 - PS657 2PS666 - PS669 2PS691 - PS692 2PS701 - PS706 2PS751 - 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 2PT001 - PT015 2PT021 - PT031 2PT041 - PT064 2PT101 - PT105 2PT121 - PT138 2PT146 - PT148 2PT161 - PT170 2PT181 - PT188 2PT211 - PT220 2PT295 2PT301 - PT309 2PT331 - PT360 2PT381 - PT399 2PT401 - PT438 2PT501 - PT517 Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: January 16, 2017 737-57A1329 17 of 56 BOEING SERVICE BULLETIN 737-57A1329 ALERTALERT ### Page 18 GroupVariable Number 2PT561 - PT565 2PT581 - PT586 2PT611 - PT621 2PT641 - PT644 2PT651 - PT656 2PT671 - PT672 2PT681 - PT685 2PT701 - PT703 2PT716 - PT717 2PT721 - PT725 2PT801 - PT834 2PT851 - PT854 2PT871 - PT886 2PT901 - PT930 2PT971 - PT973 2PT981 - PT985 2PT996 2PU001 - PU025 2PU301 2PU311 - PU313 2PV001 - PV055 2PV201 - PV209 2PV226 - PV229 2PV231 - PV237 2PV271 - PV272 2PV281 - PV287 2PV296 2PV301 - PV302 2PV351 2PV356 - PV357 2PW001 - PW054 2PW061 - PW068 2PW072 Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: January 16, 2017 737-57A1329 18 of 56 BOEING SERVICE BULLETIN 737-57A1329 ALERTALERT ### Page 19 GroupVariable Number 2PW086 - PW088 2PW091 - PW094 2PW101 - PW102 2PW106 2PW111 - PW120 2PW156 - PW157 2PW161 - PW171 2PW201 - PW252 2PW261 - PW268 2PW271 - PW276 2PW278 2PW281 - PW293 2PW296 2PW301 - PW327 2PW401 - PW408 2PW411 - PW418 2PW421 - PW424 2PW431 - PW435 2PW441 - PW450 2PW461 - PW467 2PW501 - PW504 2PW511 - PW522 2PW524 - PW550 2PW556 - PW557 2PW561 - PW564 2PW571 - PW576 2PW591 - PW596 2PW611 - PW622 2PW631 - PW637 2PW661 - PW662 2PW681 - PW683 2PW701 - PW702 2PW711 - PW717 Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: January 16, 2017 737-57A1329 19 of 56 BOEING SERVICE BULLETIN 737-57A1329 ALERTALERT ### Page 20 GroupVariable Number 2PW741 - PW742 2PW761 2PW771 2PW831 2PW851 - PW856 1PX071 1PX701 1PY001 - PY008 1PY021 3PY022 1PY031 3PY036 - PY037 3PY046 - PY048 3PY051 - PY053 3PY056 - PY057 3PY101 - PY103 3PY111 - PY113 3PY131 - PY135 3PY141 - PY143 3PY151 - PY154 3PY156 - PY157 3PY161 - PY162 3PY166 3PY191 3PY201 3PY221 - PY222 3PY231 3PY241 - PY244 3PY270 - PY275 3PY281 3PY286 1PY301 - PY304 1PY321 - PY323 Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: January 16, 2017 737-57A1329 20 of 56 BOEING SERVICE BULLETIN 737-57A1329 ALERTALERT ### Page 21 GroupVariable Number 1PY341 - PY346 1PY361 - PY362 1PY381 3PY401 3PY409 - PY411 3PY421 - PY422 3PY441 3PY451 3PY461 - PY463 3PY591 - PY595 3PY611 - PY612 3PY621 3PY631 3PY651 3PY671 - PY672 3PY721 3PY741 2. Spares Affected None. B. Concurrent Requirements None. C. Reason Accomplishment of this service bulletin will make sure that cracks are found in the upper aft skin (inspar upper skin) of the left and right wing at the rear spar from Wing Buttock Line (WBL) 159 to WBL 220. Undetected cracks in the upper aft skin may lead to the inability of a principal structural element to sustain limit load which could adversely affect the structural integrity of the airplane. During a visual inspection, a 737-400 operator found a crack in the left upper aft skin originating from a fastener hole common to the upper aft skin and strap aft of the rear spar at WBL 187. The airplane had 49,461 flight hours and 47,718 flight cycles. A total of 73 cases of the upper aft skin cracks have been reported to Boeing between 1993 and November 2015, of which 24 cases were reported in 2015. The cracks measured from 0.02 inches to 3.0 inches long. The table below contains information about crack lengths, flight cycles and number of cracks found between WBL 170 and WBL 200. Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: January 16, 2017 737-57A1329 21 of 56 BOEING SERVICE BULLETIN 737-57A1329 ALERTALERT ### Page 22 Reported crack data for 737-200/200C/300/400/500 airplanes between 1993 and 2015 Number of cracks foundFlight CyclesCrack Length 2628,000 - 69,000Less than 1 inch 3326,000 - 73,000Between 1 inch and 2 inches 1430,000 - 70,000More than 2 inches Cracks between WBL 159 and WBL 200 were also found during open hole High Frequency Eddy Current (HFEC) inspection as part of the wing rear spar upper chord splice repair in relation to SB 737-57-1318 original issue and SB 737-57A1326 original issue. Most large cracks were reported at WBL 171, 183, 187 and 200 at the end fasteners common to the straps attaching the wing trailing edge to the wing upper aft skin. Cracks between WBL 159 and WBL 220 originated from fastener holes common to the upper aft skin and strap aft of the rear spar upper chord. Analysis shows that ground loads introduce a high tension stress in the wing trailing edge skin outboard of the main landing gear beam attachment and high bearing load transfer occurs at the end fasteners of the straps attaching the trailing edge skin to the upper aft skin. This combination of ground loads and bending loads at the skin/strap joint lead to cracks originating from fastener holes which can then lead to fatigue. Failure occurs with the combination of skin and rear spar upper chord cracking. There has been no report of the upper chord cracking to date at this location. Boeing has determined that the existing inspection programs are not sufficient to find such cracks before they could grow to a critical length. This service bulletin provides instructions for inspection of the upper aft skin aft of the rear spar for any crack from WBL 159 to WBL 220 to make sure they are found and repaired before they reach a critical length. Boeing Service Related Problem (SRP) 737-SRP-57-0302 is related to this service bulletin. Boeing Fleet Team Digest (FTD) 737 FTD 57-15002 is related to this service bulletin. This table is provided to operators for planning purposes only. Refer to the applicable sections for more information. D. Description Group 1: Boeing endorses the new FAA rules related to Limit of Validity (LOV) and recommends immediate and permanent removal from service of any airplanes upon reaching the LOV, whether or not it is operated under FAA jurisdiction. As such, Boeing no longer provides maintenance instructions for airplanes that have accumulated flight cycles beyond the LOV. 737 Classic airplanes line numbers 1-291 have accumulated flight cycles beyond the LOV of the maintenance program. 14 CFR 121.1115 and 129.115 prohibit operation of an airplane beyond its LOV. Group 2-3: Do the work that follows on the left and right wing from Wing Buttock Line (WBL) 159 to WBL 220: Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: January 16, 2017 737-57A1329 22 of 56 BOEING SERVICE BULLETIN 737-57A1329 ALERTALERT ### Page 23 Group 2-3: 1. Deactivate the trailing edge flap system. 2. In areas without an external repair, do a surface High Frequency Eddy Current (HFEC) inspection for any crack in the upper aft skin. If any crack is found contact The Boeing Company for repair instructions and do the repair. Repeat inspections in unrepaired areas. If no crack is found repeat the inspections. 3. In areas with an external repair, do surface HFEC, Low Frequency Eddy Current (LFEC) and detailed inspections for any crack. If any crack is found contact The Boeing Company for repair instructions and do the repair. If no crack is found repeat the inspections. 4. Activate the trailing edge flap system. The work in this service bulletin is done in the maintenance zone(s) given below. Group 1: Affected Maintenance Zones ZoneModel 3-5, 4-5737-100, 737-200, 737-200C Group 2: Affected Maintenance Zones ZoneModel 305, 405737-300, 737-400, 737-500 Group 3: Affected Maintenance Zones ZoneModel 3-5, 4-5737-200, 737-200C E. Compliance The Federal Aviation Administration (FAA) will possibly release an Airworthiness Directive related to this service bulletin. The Airworthiness Directive will make the compliance tasks and times given in this service bulletin mandatory. Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: January 16, 2017 737-57A1329 23 of 56 BOEING SERVICE BULLETIN 737-57A1329 ALERTALERT ### Page 24 Group 1: Boeing endorses the new FAA rules related to Limit of Validity (LOV) and recommends immediate and permanent removal from service of any airplanes upon reaching the LOV, whether or not it is operated under FAA jurisdiction. As such, Boeing no longer provides maintenance instructions for airplanes that have accumulated flight cycles beyond the LOV. 737 Classic airplanes line numbers 1-291 have accumulated flight cycles beyond the LOV of the maintenance program. 14 CFR 121.1115 and 129.115 prohibit operation of an airplane beyond its LOV. Therefore these airplanes have been excluded from this service bulletin. When more than one OPTION is given for a CONDITION, do only one of the OPTION numbers. When more than one ACTION is given for a CONDITION number or an OPTION number, do all of the ACTION numbers for that CONDITION number or OPTION number. A logic diagram showing compliance tasks and compliance times is included as an aid in APPENDIX A, APPENDIX B, APPENDIX C and APPENDIX D. Accomplish the required actions, based on the applicable conditions in Tables 1 through 4, in accordance with Paragraph 3. Accomplishment Instructions. The term "external repair" is defined as any combination of a repair doubler and repair tripler. Group 2: Table 1: Surface High Frequency Eddy Current (HFEC) inspection of the upper aft skin in areas with no external repair on the left and right wing from Wing Buttock Line (WBL) 159 to WBL 220 Repeat Interval (Not to Exceed) Compliance Time (Whichever Occurs Later) ActionCondition -Within 4,500 flight cycles af- ter the original issue date of this service bul- letin. Before 17,000 total flight cy- cles. Do PART 1 : SURFACE HFEC INSPECTION OF THE UPPER AFT SKIN FROM WBL 159 TO WBL 220 IN AREAS WITH- OUT AN EXTERNAL REPAIR for any crack. Airplanes that have not done an Open Hole HFEC inspection of the fastener holes common to the upper aft skin and strap aft of the rear spar in the inspection area. (a) -Within 4,500 flight cycles af- ter the original issue date of this service bul- letin. Before 17,000 total flight cycles or within 9,000 flight cycles af- ter the last Open Hole HFEC inspec- tion was done, whichever oc- curs later. Do PART 1 : SURFACE HFEC INSPECTION OF THE UPPER AFT SKIN FROM WBL 159 TO WBL 220 IN AREAS WITH- OUT AN EXTERNAL REPAIR for any crack. Airplanes that have done an Open Hole HFEC in- spection of the fastener holes common to the upper aft skin and strap aft of the rear spar in the inspection area. (a) Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: January 16, 2017 737-57A1329 24 of 56 BOEING SERVICE BULLETIN 737-57A1329 ALERTALERT ### Page 25 Group 2: Table 1: Surface High Frequency Eddy Current (HFEC) inspection of the upper aft skin in areas with no external repair on the left and right wing from Wing Buttock Line (WBL) 159 to WBL 220 Repeat Interval (Not to Exceed) Compliance Time (Whichever Occurs Later) ActionCondition 4,500 flight cycles.-Repeat PART 1: SUR- FACE HFEC INSPEC- TION OF THE UPPER AFT SKIN FROM WBL 159 TO WBL 220 IN AR- EAS WITHOUT AN EX- TERNAL REPAIR for any crack. CONDITION 1: NO CRACK FOUND IN THE UPPER AFT SKIN -Before further flight.CONDITION 2 (ACTION 1): Contact The Boeing Company for repair in- struction and do the re- pair. CONDITION 2: ANY CRACK FOUND IN THE UPPER AFT SKIN 4,500 flight cycles.-CONDITION 2 (ACTION 2): Repeat PART 1: SURFACE HFEC IN- SPECTION OF THE UP- PER AFT SKIN FROM WBL 159 TO WBL 220 IN AREAS WITHOUT AN EXTERNAL REPAIR for any crack in the unre- paired areas. (a) Accomplishment of an open hole HFEC inspection of the fastener holes common to the upper aft skin and strap aft of the rear spar in the inspection area is met if the inspection was done in accordance with 737 NDT Manual Part 6, 51-00-00 Procedure 1 or Procedure 16 during the accomplishment of one of the following: – 737-300 SRM 57-20-10 Repair 4, 737-400 SRM 57-20-10 Repair 4, or 737-500 SRM 57-20-10 Repair 4. – Boeing ODA FAA Form 8100-9 approved upper rear spar chord replacement repair. The inspection area is defined in FIGURE 1 and FIGURE 3. Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: January 16, 2017 737-57A1329 25 of 56 BOEING SERVICE BULLETIN 737-57A1329 ALERTALERT ### Page 26 Group 2, Configuration 2: Table 2: Surface High Frequency Eddy Current (HFEC), Low Frequency Eddy Current (LFEC) & Detailed Inspection of the upper aft skin and external repair in areas with external repair on the left or right wing from Wing Buttock Line (WBL) 159 to WBL 220 Repeat Interval (Not to Exceed) Compliance Time (Whichever Occurs Later) ActionCondition -Within 2,000 flight cycles af- ter the original issue date of this service bul- letin. Before 17,000 total flight cycles or within 9,000 flight cycles af- ter the installa- tion of the exter- nal repair, whichever oc- curs later. Do PART 2: SURFACE HFEC, LFEC AND DE- TAILED INSPECTION IN AREAS WITH AN EXTER- NAL REPAIR for any crack. All Airplanes with an exter- nal repair. 2,000 flight cycles.-Repeat PART 2: SUR- FACE HFEC, LFEC AND DETAILED INSPECTION IN AREAS WITH AN EX- TERNAL REPAIR for any crack. CONDITION 3: NO CRACK FOUND IN THE EXTERNAL REPAIR AREA -Before further flight.Contact The Boeing Company for repair in- structions and do the re- pair. CONDITION 4: ANY CRACK FOUND IN THE EXTERNAL REPAIR AREA Group 3: Table 3: Surface High Frequency Eddy Current (HFEC) inspection of the upper aft skin in areas with no external repair on the left and right wing from Wing Buttock Line (WBL) 159 to WBL 220 Repeat Interval (Not to Exceed) Compliance Time (Whichever Occurs Later) ActionCondition -Within 4,500 flight cycles af- ter the original issue date of this service bul- letin. Before 14,000 total flight cy- cles. Do PART 1 : SURFACE HFEC INSPECTION OF THE UPPER AFT SKIN FROM WBL 159 TO WBL 220 IN AREAS WITH- OUT AN EXTERNAL REPAIR for any crack. Airplanes that have not done an Open Hole HFEC inspection of the fastener holes common to the upper aft skin and strap aft of the rear spar in the inspection area. (a) Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: January 16, 2017 737-57A1329 26 of 56 BOEING SERVICE BULLETIN 737-57A1329 ALERTALERT ### Page 27 Group 3: Table 3: Surface High Frequency Eddy Current (HFEC) inspection of the upper aft skin in areas with no external repair on the left and right wing from Wing Buttock Line (WBL) 159 to WBL 220 Repeat Interval (Not to Exceed) Compliance Time (Whichever Occurs Later) ActionCondition -Within 4,500 flight cycles af- ter the original issue date of this service bul- letin. Before 14,000 total flight cycles or within 7,000 flight cycles af- ter the last Open Hole HFEC inspec- tion was done, whichever oc- curs later. Do PART 1 : SURFACE HFEC INSPECTION OF THE UPPER AFT SKIN FROM WBL 159 TO WBL 220 IN AREAS WITH- OUT AN EXTERNAL REPAIR for any crack. Airplanes that have done an Open Hole HFEC in- spection of the fastener holes common to the upper aft skin aft of the rear spar and strap in the inspection area. (a) 4,500 flight cycles.-Repeat PART 1: SUR- FACE HFEC INSPEC- TION OF THE UPPER AFT SKIN FROM WBL 159 TO WBL 220 IN AR- EAS WITHOUT AN EX- TERNAL REPAIR for any crack. CONDITION 1: NO CRACK FOUND IN THE UPPER AFT SKIN. -Before further flight.CONDITION 2 (ACTION 1): Contact The Boeing Company for repair in- structions and do the re- pair. CONDITION 2: ANY CRACK FOUND IN THE UPPER AFT SKIN. 4,500 flight cycles.-CONDITION 2 (ACTION 2): Repeat PART 1: SURFACE HFEC IN- SPECTION OF THE UP- PER AFT SKIN FROM WBL 159 TO WBL 220 IN AREAS WITHOUT AN EXTERNAL REPAIR for any crack in the unre- paired areas. (a) Accomplishment of an open hole HFEC inspection of the fastener holes common to the upper aft skin and strap aft of the rear spar in the inspection area is met if the inspection was done in accordance with 737 NDT Manual Part 6, 51-00-00 Procedure 1 or Procedure 16 during the accomplishment of Boeing ODA FAA Form 8100-9 approved upper rear spar chord replacement repair. The inspection area is defined in FIGURE 1 and FIGURE 3. Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: January 16, 2017 737-57A1329 27 of 56 BOEING SERVICE BULLETIN 737-57A1329 ALERTALERT ### Page 28 Group 3, Configuration 2: Table 4: Surface High Frequency Eddy Current (HFEC), Low Frequency Eddy Current (LFEC) & Detailed Inspection of the upper aft skin and external repair in areas with external repair on the left or right wing from Wing Buttock Line (WBL) 159 to WBL 220 Repeat Interval (Not to Exceed) Compliance Time (Whichever Occurs Later) ActionCondition -Within 1,500 flight cycles af- ter the original issue date of this service bul- letin. Before 14,000 total flight cycles or within 7,000 flight cycles af- ter the installa- tion of the exter- nal repair, whichever oc- curs later. Do PART 2: SURFACE HFEC, LFEC AND DE- TAILED INSPECTION IN AREAS WITH AN EXTER- NAL REPAIR for any crack. All Airplanes with an exter- nal repair. 1,500 flight cycles.-Repeat PART 2: SUR- FACE HFEC, LFEC AND DETAILED INSPECTION IN AREAS WITH AN EX- TERNAL REPAIR for any crack. CONDITION 3: NO CRACK FOUND IN THE EXTERNAL REPAIR AREA. -Before further flight.Contact The Boeing Company for repair in- struction and do the re- pair. CONDITION 4: ANY CRACK FOUND IN THE EXTERNAL REPAIR AREA. F. Approval This service bulletin was examined by the Federal Aviation Administration (FAA). The changes specified in this service bulletin comply with the applicable regulations and are FAA approved, as well as European Aviation Safety Agency (EASA)/Joint Aviation Authorities (JAA) approved for all EASA/JAA approved airplanes listed in the service bulletin effectivity. This service bulletin and its approval were based on the airplane in its original Boeing delivery configuration or as modified by other approved Boeing changes. If an airplane has a non-Boeing modification or repair that affects a component or system also affected by this service bulletin, the operator is responsible for obtaining appropriate regulatory agency approval before incorporating this service bulletin. G. Manpower The table below shows an estimate of the task hours necessary to do this service bulletin 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 Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: January 16, 2017 737-57A1329 28 of 56 BOEING SERVICE BULLETIN 737-57A1329 ALERTALERT ### Page 29 • Time to cure the materials • Time to make the parts • Time to find the tools Elapsed HoursTask HoursNumber of PersonsTask 0.250.251Open Access 1.651.651Figure 1 2.302.301Figure 2 (a) 1.651.651Figure 3 2.302.301Figure 4 (a) 0.250.251Close Access 8.408.40TOTAL FOR EACH AIRPLANE (a) The work in this Figure is for areas where a typical external repair is installed on the upper aft skin. The task hours necessary may vary depending on the size of the repair. H. Weight and Balance Changes None. I. Electrical Load Data Not changed. J. References 1. Existing Data: a. Boeing Service Bulletin 737-57-1318, 737-57A1326 b. Boeing Service Letter 737-SL-51-042 c. Boeing Service Related Problem (SRP) 737-SRP-57-0302 d. Service Bulletin Index D6-19567 e. Standard Overhaul Practices Manual (SOPM) 20-50-01 f. 737 Fleet Team Digest (FTD) 57-15002 g. 737 Non-Destructive Testing (NDT) Manual Part 6, 51-00-00, Part 6, 51-00-26 h. 737-100/200 Aircraft Maintenance Manual (AMM) 27-51-00 i. 737-300/400/500 Aircraft Maintenance Manual (AMM) 27-51-00 j. 737-300 Structural Repair Manual (SRM) 57-20-10 Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: January 16, 2017 737-57A1329 29 of 56 BOEING SERVICE BULLETIN 737-57A1329 ALERTALERT ### Page 30 k. 737-400 Structural Repair Manual (SRM) 57-20-10 l. 737-500 Structural Repair Manual (SRM) 57-20-10 2. Data Supplied with this Service Bulletin: None. 3. Installation Drawings Used in the Preparation of this Service Bulletin: TitleDrawing Number Panel Instl -Upper Inbd. Fixed Trailing Edge, Wing.65-50820 Rib Installation-Inspar. WBL 227.065-45450 Rib Installation-Inspar. WBL 198.6065-45449 Rib Installation-Inspar. WBL 183.4065-45447 Rib Installation-Inspar. WBL 157.065-45446 Rib Installation-Inspar. WBL 135.565-45445 Panel Instl - Inspar Wing, Upper65-45407 Rear Spar Installation-Wing65-45321 The table above lists applicable drawings used to prepare this service bulletin. The drawings are not necessary to make the specified changes, and are not supplied with this service bulletin. The drawings may not be applicable to all airplane configurations or operators. K. Publications Affected 1. Publications: None. 2. Damage Tolerance Based Structural Inspections: Boeing has evaluated the repairs and/or changes in this service bulletin for effects on Fatigue Critical Structure (FCS) and for changes to Damage Tolerance Inspections (DTI) required in the Maintenance Program. This service bulletin affects FCS but no new DTIs are necessary. L. Interchangeability and Intermixability of Parts Accomplishment of this service bulletin does not affect interchangeability or intermixability of parts. M. Software Accomplishment Summary Not affected. Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: January 16, 2017 737-57A1329 30 of 56 BOEING SERVICE BULLETIN 737-57A1329 ALERTALERT ### Page 31 2. MATERIAL INFORMATION A. Material - Price and Availability None. B. Industry Support Information Boeing warranty remedies are not available for the inspection 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: January 16, 2017 737-57A1329 31 of 56 BOEING SERVICE BULLETIN 737-57A1329 ALERTALERT ### Page 32 Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: January 16, 2017 737-57A1329 32 of 56 BOEING SERVICE BULLETIN 737-57A1329 ALERTALERT BLANK PAGE ### Page 33 3. ACCOMPLISHMENT INSTRUCTIONS A. GENERAL INFORMATION CAUTION: KEEP THE WORK AREA, WIRES AND ELECTRICAL BUNDLES CLEAN OF METAL PARTICLES OR CONTAMINATION WHEN YOU USE TOOLS. UNWANTED MATERIAL, METAL PARTICLES OR CONTAMINATION CAUGHT IN WIRE BUNDLES CAN CAUSE DAMAGE TO THE BUNDLES. DAMAGED WIRE BUNDLES CAN CAUSE SPARKS OR OTHER ELECTRICAL DAMAGE. NOTE: 1. Manual titles are referred to by acronyms. Refer to Paragraph 1.J., References, for definition of the acronyms. 2. Obey all of the warnings and cautions given in the specified manual sections. 3. Unless shown differently, these dimensions and tolerances are used: – Linear dimensions are in inches – Tolerance on linear dimensions, other than rivet and bolt edge margins, is plus or minus 0.03 inch – Tolerance on rivet and bolt edge margin is plus or minus 0.05 inch – Angular tolerance is plus or minus 2 degrees – Hole dimensions for standard solid rivets and fasteners are in Structural Repair Manual (SRM) Chapter 51 – Torque Values: — Values for structural fasteners are given in 737 Structural Repair Manual, Chapter 51. — Values for airframe maintenance tasks are included in Chapter 20 of 737 Aircraft Maintenance Manual (AMM). — Values for electrical maintenance tasks are included in Chapter 20 of Standard Wiring Practices Manual (SWPM). — Values for engine maintenance tasks are included in Chapter 70 of 737 Aircraft Maintenance Manual (AMM). — Non-standard torque values for maintenance tasks are included in the applicable installation step. 4. Use the approved fastener, process and material substitutions in accordance with SRM Chapter 51. 5. 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. Refer to SOPM 20-50-01 for alternate full threaded fasteners (screws) needed for installation in this service bulletin. 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. Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: January 16, 2017 737-57A1329 33 of 56 BOEING SERVICE BULLETIN 737-57A1329 ALERTALERT ### Page 34 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. 9. Refer to Appendix A through D for logic diagrams. Logic diagrams are provided as an aid only. Information contained in Paragraph 1.E., Compliance is the primary source for compliance times. Information in Paragraph 3.B., Work Instructions is the primary source for tasks required for compliance. 10. 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. 11. Use of colors in Figures is based on guidance from the ATA e-Business Program (ATA) iSpec 2200. 12. When more than one OPTION is given for a CONDITION, do only one of the OPTION numbers. When more than one ACTION is given for a CONDITION number or an OPTION number, do all of the ACTION numbers for that CONDITION number or OPTION number. 13. The compliance times for the actions in Paragraph 3.B., WORK INSTRUCTIONS are in Paragraph 1.E., Compliance. 14. Some steps in the Work Instructions are labeled as Required for Compliance (RC). If this service bulletin is mandated by an Airworthiness Directive (AD), then the steps labeled as RC, including sub-steps under an RC step and any figures identified in an RC step, must be done to comply with the AD. If a step or sub-step is labeled "RC Exempt," then the RC requirement is removed from that step or sub-step. An Alternative Method of Compliance (AMOC) is required for any deviations to RC steps, including sub-steps and identified figures. Steps not labeled as RC may be deviated from using accepted methods in accordance with the operator's maintenance or inspection program without obtaining approval of an AMOC. This is provided that the RC steps, including sub-steps and identified figures, can still be done as specified, and the airplane can be put back in an airworthy condition. Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: January 16, 2017 737-57A1329 34 of 56 BOEING SERVICE BULLETIN 737-57A1329 ALERTALERT ### Page 35 15. The term "external repair" is defined as any combination of a repair doubler and repair tripler. B. WORK INSTRUCTIONS Group 1: Boeing endorses the new FAA rules related to Limit of Validity (LOV) and recommends immediate and permanent removal from service of any airplanes upon reaching the LOV, whether or not it is operated under FAA jurisdiction. As such, Boeing no longer provides maintenance instructions for airplanes that have accumulated flight cycles beyond the LOV. 737 Classic airplanes line numbers 1-291 have accumulated flight cycles beyond the LOV of the maintenance program. 14 CFR 121.1115 and 129.115 prohibit operation of an airplane beyond its LOV. 1. Deactivate the trailing edge flap system. Refer to 737-100/200 AMM 27-51-00 and 737-300/400/500 AMM 27-51-00 as an accepted procedure. 2. Group 2-3: RC - Do PART 1: SURFACE HFEC INSPECTION OF THE UPPER AFT SKIN FROM WBL 159 TO WBL 220 IN AREAS WITHOUT AN EXTERNAL REPAIR for any crack. a. CONDITION 1: NO CRACK FOUND IN THE UPPER AFT SKIN (1) REPEAT PART 1: SURFACE HFEC INSPECTION OF THE UPPER AFT SKIN FROM WBL 159 TO WBL 220 IN AREAS WITHOUT AN EXTERNAL REPAIR for any crack at the times specified in Paragraph 1.E., Compliance. b. CONDITION 2: ANY CRACK FOUND IN THE UPPER AFT SKIN (1) CONDITION 2 (ACTION 1): Contact The Boeing Company for repair instructions and do the repair. (2) CONDITION 2 (ACTION 2): Repeat PART 1: SURFACE HFEC INSPECTION OF THE UPPER AFT SKIN FROM WBL 159 TO WBL 220 IN AREAS WITHOUT AN EXTERNAL REPAIR for any crack in the unrepaired areas at the times specified in Paragraph 1.E., Compliance. 3. Group 2-3, Configuration 2: RC - Do PART 2: SURFACE HFEC, LFEC AND DETAILED INSPECTION IN AREAS WITH AN EXTERNAL REPAIR for any crack. a. CONDITION 3: NO CRACK FOUND IN THE EXTERNAL REPAIR AREA (1) Repeat PART 2: SURFACE HFEC, LFEC AND DETAILED INSPECTION IN AREAS WITH AN EXTERNAL REPAIR for any crack at the times specified in Paragraph 1.E., Compliance. b. CONDITION 4: ANY CRACK FOUND IN THE EXTERNAL REPAIR AREA (1) Contact The Boeing Company for repair instructions and do the repair. 4. Activate the trailing edge flap systems. Refer to 737-100/200 AMM 27-51-00 and 737-300/400/500 AMM 27-51-00 as an accepted procedure. Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: January 16, 2017 737-57A1329 35 of 56 BOEING SERVICE BULLETIN 737-57A1329 ALERTALERT ### Page 36 5. Put the airplane back to a serviceable condition. Group 2-3: PART 1: SURFACE HFEC INSPECTION OF THE UPPER AFT SKIN FROM WBL 159 TO WBL 220 IN AREAS WITHOUT AN EXTERNAL REPAIR 1. Do a surface High Frequency Eddy Current (HFEC) inspection of the upper aft skin on the left and right wing for any crack in accordance with FIGURE 1 and FIGURE 3. Group 2-3, Configuration 2: PART 2: SURFACE HFEC, LFEC AND DETAILED INSPECTION FROM WBL 159 TO WBL 220 IN AREAS WITH AN EXTERNAL REPAIR 1. Do a surface High Frequency Eddy Current (HFEC), Low Frequency Eddy Current (LFEC) and detailed inspections in areas with an external repair on the left wing for any crack in accordance with FIGURE 2. 2. Do a surface High Frequency Eddy Current (HFEC), Low Frequency Eddy Current (LFEC) and detailed inspections in areas with an external repair on the right wing for any crack in accordance with FIGURE 4. Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: January 16, 2017 737-57A1329 36 of 56 BOEING SERVICE BULLETIN 737-57A1329 ALERTALERT ### Page 37 (OCR) BOEING SERVICE BULLETIN 737-57A1329 ALERT ALERT This Figure applies only to: Group 2-3. LEFT WING UPPER AFT WBL 171 SKIN _S-6 WBL . S-5 187 „S-4 WBL 198 2.5 REAR SPAR BD EXAMPLE FREEZE PLUG REPAIR LOCATION 25.0 A-A INSPECTION ZONE 2533814 FIGURE 1: LEFT WING UPPER AFT SKIN - WBL 159 TO WBL 220 IN AREAS WITHOUT AN EXTERNAL REPAIR - INSPECTION (SHEET 1 OF 3) Original Issue: January 16, 2017 Export Controlled ECCN: 9E991 - BOEING 737-57A1329 PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. 37 of 56 ### Page 38 (OCR) BOEING SERVICE BULLETIN 737-57A1329 ALERT ALERT STRAP UPPER AFT SKIN FREEZE PLUG FWD — UPPER REAR - CHORD SPAR WEB TYPICAL PROFILE WITH FREEZE PLUG REPAIR B-B UPPER AFT SKIN STRAP FWD SUPPER REAR CHORD SPAR WEB TYPICAL PROFILE WITHOUT FREEZE PLUG REPAIR C-C 2536191 FIGURE 1: LEFT WING UPPER AFT SKIN - WBL 159 TO WBL 220 IN AREAS WITHOUT AN EXTERNAL REPAIR - INSPECTION (SHEET 2 OF 3) Original Issue: January 16, 2017 Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished 737-57A1329 Work - See page 1 for details. 38 of 56 ### Page 39 More DataQtyIdentificationNameTaskStep (a) (b) (c)--UPPER AFT SKINInspect1 (a) Do a surface HFEC inspection for any crack along the forward edge of the fastener holes in the inspection area, using a straight edge as a guide, in accordance with 737 NDT Manual Part 6, 51-00-00 Procedure 4 or Procedure 23. Align the straight edge with the countersink forward edge and scan the probe from countersink-to-countersink. Inspect the entire length of the inspection area. Repeat the procedure along the aft edge of the fastener holes. If a crack indication is found determine if the crack indication is due to a crack or the edge of the freeze plug by marking its location. (b) At fastener locations that have a freeze plug, do a surface HFEC inspection for any crack in the upper aft skin around the freeze plug outer diameter in accordance with 737 NDT Manual Part 6, 51-00-00 Procedure 4 or Procedure 23. A freeze plug repair can be installed anywhere in the inspection area. (c) It is not necessary to do this surface HFEC inspection in areas covered by external repair. FIGURE 1: LEFT WING UPPER AFT SKIN - WBL 159 TO WBL 220 IN AREAS WITHOUT AN EXTERNAL REPAIR - INSPECTION (SHEET 3 OF 3) Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: January 16, 2017 737-57A1329 39 of 56 BOEING SERVICE BULLETIN 737-57A1329 ALERTALERT ### Page 40 (OCR) BOEING SERVICE BULLETIN 737-57A1329 ALERT ALERT This Figure applies only to: Group 2-3, Configuration 2. B LEFT WING -T SK .S-4 EDGE OF 183.40 REPAIR WBL TRIPLER - = EDGE OF REPAIR DOUBLER NBD HFEC INSPECTION REPAIR (TYPICAL) LFEC INSPECTION A-A 2533985 FIGURE 2: LEFT WING UPPER AFT SKIN- WBL 159 TO WBL 220 IN AREAS WITH AN EXTERNAL REPAIR - INSPECTION (SHEET 1 OF 3) Original Issue: January 16, 2017 PROPRIETARY - Copyright © Unpublished Export Controlled ECCN: 9E991 - BOEING 737-57A1329 Work - See page 1 for details. 40 of 56 ### Page 41 (OCR) BOEING SERVICE BULLETIN 737-57A1329 ALERT ALERT WBL UPPER 157 AFT SKIN WBL 183.40 * + * * EDGE OF EDGE OF REPAIR REPAIR DOUBLER REPAIR TRIPLER (TYPICAL) DETAILED INSPECTION B-B REPAIR REPAIR TRIPLER DOUBLER UPPER AFT STRAP SKIN FWD — UPPER REAR CHORD SPAR WEB 2534018 C-C FIGURE 2: LEFT WING UPPER AFT SKIN - WBL 159 TO WBL 220 IN AREAS WITH AN EXTERNAL REPAIR - INSPECTION (SHEET 2 OF 3) Original Issue: January 16, 2017 PROPRIETARY - Copyright © Unpublished Export Controlled ECCN: 9E991 - BOEING 737-57A1329 Work - See page 1 for details. 41 of 56 ### Page 42 More DataQtyIdentificationNameTaskStep (a)--UPPER AFT SKINInspect1 (b)--UPPER AFT SKINInspect2 (c)--REPAIR DOUBLERInspect3 (d)--REPAIR TRIPLERInspect4 (a) Do a surface HFEC inspection for any crack in the upper aft skin around the edge of the repair doubler in accordance with 737 NDT Manual Part 6, 51-00-00 Procedure 4 or Procedure 23. If a fillet sealant is present, do the surface HFEC inspection at the edge of the fillet sealant. (b) Do a LFEC inspection for any crack in the upper aft skin around the heads of the end fasteners of the repair doubler in accordance with 737 NDT Manual Part 6, 51-00-26. (c) Do a LFEC inspection for any crack in the repair doubler around the fastener heads common to the repair tripler in accordance with 737 NDT Manual Part 6, 51-00-26. (d) Do a detailed inspection of the repair tripler for any crack. FIGURE 2: LEFT WING UPPER AFT SKIN - WBL 159 TO WBL 220 IN AREAS WITH AN EXTERNAL REPAIR - INSPECTION (SHEET 3 OF 3) Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: January 16, 2017 737-57A1329 42 of 56 BOEING SERVICE BULLETIN 737-57A1329 ALERTALERT ### Page 43 (OCR) BOEING SERVICE BULLETIN 737-57A1329 ALERT ALERT This Figure applies only to: Group 2-3. RIGHT WING WBL UPPER 157 WBL 159 WBL SKIN AFT S-6 S-5. WBL + + 187 S-4 WBL 198 + + · + 72.5 REAR SPAR + + INBD B EXAMPLE FREEZE PLUG REPAIR LOCATION 25.0 INSPECTION ZONE A-A FIGURE 3: RIGHT WING UPPER AFT SKIN - WBL 159 TO WBL 220 IN AREAS WITHOUT AN EXTERNAL REPAIR - INSPECTION (SHEET 1 OF 3) Original Issue: January 16, 2017 Export Controlled ECCN: 9E991 - BOEING 737-57A1329 PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. 43 of 56 ### Page 44 (OCR) BOEING SERVICE BULLETIN 737-57A1329 ALERT ALERT UPPER AFT STRAP SKIN FREEZE PLUG FWD UPPER CHORD REAR SPAR WEB TYPICAL PROFILE WITH FREEZE PLUG REPAIR B-B UPPER AFT STRAP SKIN FWD UPPER CHORD REAR SPAR WEB TYPICAL PROFILE WITHOUT FREEZE PLUG REPAIR 2536195 C-C FIGURE 3: RIGHT WING UPPER AFT SKIN - WBL 159 TO WBL 220 IN AREAS WITHOUT AN EXTERNAL REPAIR - INSPECTION (SHEET 2 OF 3) Original Issue: January 16, 2017 Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished 737-57A1329 Work - See page 1 for details. 44 of 56 ### Page 45 More DataQtyIdentificationNameTaskStep (a) (b) (c)--UPPER AFT SKINInspect1 (a) Do a surface HFEC inspection for any crack along the forward edge of the fastener holes in the inspection area, using a straight edge as a guide, in accordance with 737 NDT Manual Part 6, 51-00-00 Procedure 4 or Procedure 23. Align the straight edge with the countersink forward edge and scan the probe from countersink-to-countersink. Inspect the entire length of the inspection area. Repeat the procedure along the aft edge of the fastener holes. If a crack indication is found determine if the crack indication is due to a crack or the edge of the freeze plug by marking its location. (b) At fastener locations that have a freeze plug, do a surface HFEC inspection for any crack in the upper aft skin around the freeze plug outer diameter in accordance with 737 NDT Manual Part 6, 51-00-00 Procedure 4 or Procedure 23. A freeze plug repair can be installed anywhere in the inspection area. (c) It is not necessary to do this surface HFEC inspection in areas covered by external repair. FIGURE 3: RIGHT WING UPPER AFT SKIN - WBL 159 TO WBL 220 IN AREAS WITHOUT AN EXTERNAL REPAIR - INSPECTION (SHEET 3 OF 3) Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: January 16, 2017 737-57A1329 45 of 56 BOEING SERVICE BULLETIN 737-57A1329 ALERTALERT ### Page 46 (OCR) BOEING SERVICE BULLETIN 737-57A1329 ALERT ALERT This Figure applies only to: Group 2-3, Configuration 2. RIGHT WING WBL 157 UPPEF S-4 AFT SKIN 183.40 WBL EDGE OF REPAIR TRIPLER EDGE OF REPAIR DOUBLER INBD HFEC INSPECTION REPAIR (TYPICAL) LFEC INSPECTION A-A 2534012 FIGURE 4: RIGHT WING UPPER AFT SKIN - WBL 159 TO WBL 220 IN AREAS WITH AN EXTERNAL REPAIR - INSPECTION (SHEET 1 OF 3) Original Issue: January 16, 2017 PROPRIETARY - Copyright © Unpublished Export Controlled ECCN: 9E991 - BOEING 737-57A1329 Work - See page 1 for details. 46 of 56 ### Page 47 (OCR) BOEING SERVICE BULLETIN 737-57A1329 ALERT ALERT WBL 157 UPPER S-4. AFT SKIN + WBL 183.40 + + +. -+ EDGE OF REPAIR EDGE OF DETAILED INSPECTION TRIPLER REPAIR DOUBLER REPAIR INBD (TYPICAL) REPAIR B-B TRIPLER REPAIR DOUBLER UPPER AFT STRAP SKIN FWD UPPER CHORD — REAR SPAR WEB 2534019 FIGURE 4: RIGHT WING UPPER AFT SKIN - WBL 159 TO WBL 220 IN AREAS WITH AN EXTERNAL REPAIR - INSPECTION (SHEET 2 OF 3) Original Issue: January 16, 2017 Export Controlled ECCN: 9E991 - BOEING 737-57A1329 PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. 47 of 56 ### Page 48 More DataQtyIdentificationNameTaskStep (a)--UPPER AFT SKINInspect1 (b)--UPPER AFT SKINInspect2 (c)--REPAIR DOUBLERInspect3 (d)--REPAIR TRIPLERInspect4 (a) Do a surface HFEC inspection for any crack in the upper aft skin around the edge of the repair doubler in accordance with 737 NDT Manual Part 6, 51-00-00 Procedure 4 or Procedure 23. If a fillet sealant is present, do the surface HFEC inspection at the edge of the fillet sealant. (b) Do a LFEC inspection for any crack in the upper aft skin around the heads of the end fasteners of the repair doubler in accordance with 737 NDT Manual Part 6, 51-00-26. (c) Do a LFEC inspection for any crack in the repair doubler around the fastener heads common to the repair tripler in accordance with 737 NDT Manual Part 6, 51-00-26. (d) Do a detailed inspection of the repair tripler for any crack. FIGURE 4: RIGHT WING UPPER AFT SKIN - WBL 159 TO WBL 220 IN AREAS WITH AN EXTERNAL REPAIR - INSPECTION (SHEET 3 OF 3) Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: January 16, 2017 737-57A1329 48 of 56 BOEING SERVICE BULLETIN 737-57A1329 ALERTALERT ### Page 49 This Appendix applies only to: Group 2. Logic diagrams are provided as an aid only. Information contained in Paragraph 1.E., Compliance is the primary source for compliance times. Information contained in Paragraph 3.B., Work Instructions is the primary source for tasks required for compliance. 1. The table below gives the description for the parts and conditions called out in the logic diagrams. DescriptionTitle SURFACE HFEC INSPECTION OF THE UPPER AFT SKIN FROM WBL 159 TO WBL 220 IN AREAS WITHOUT AN EXTERNAL REPAIR PART 1 NO CRACK FOUND IN THE UPPER AFT SKIN.CONDITION 1 ANY CRACK FOUND IN THE UPPER AFT SKIN.CONDITION 2 2. The table below gives the description for the flag notes called out in the logic diagram. DescriptionFlag Note Letter Accomplishment of an open hole HFEC inspection of the fastener holes common to the upper aft skin and strap aft of the rear spar in the inspection area is met if the inspection was done in accordance with 737 NDT Manual Part 6, 51-00-00 Procedure 1 or Procedure 16 during the accomplishment of one of the following: (a) – 737-300 SRM 57-20-10 Repair 4, 737-400 SRM 57-20-10 Repair 4, or 737-500 SRM 57-20-10 Repair 4. – Boeing ODA FAA Form 8100-9 approved upper rear spar chord replace- ment repair. The inspection area is defined in FIGURE 1 and FIGURE 3. APPENDIX A: LOGIC DIAGRAM FOR PARAGRAPH 1.E. COMPLIANCE: TABLE 1: SURFACE HIGH FREQUENCY EDDY CURRENT (HFEC) INSPECTION OF THE UPPER AFT SKIN ON THE LEFT AND RIGHT WING FROM WING BUTTOCK LINE (WBL) 159 TO WBL 220 (SHEET 1 OF 2) Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: January 16, 2017 737-57A1329 49 of 56 BOEING SERVICE BULLETIN 737-57A1329 ALERTALERT ### Page 50 (OCR) BOEING SERVICE BULLETIN 737-57A1329 ALERT ALERT AIRPLANES THAT HAVE NOT DONE AN OPEN HOLE HFEC INSPECTION OF THE FASTENER HOLES COMMON TO THE UPPER AFT SKIN AND STRAP AFT OF THE REAR SPAR IN THE INSPECTION AREA (a) AIRPLANES THAT HAVE DONE AN OPEN HOLE HFEC INSPECTION OF THE FASTENER HOLES COMMON TO THE UPPER AFT SKIN AND STRAP AFT OF THE REAR SPAR IN THE INSPECTION AREA (a) WHICHEVER OCCURS LATER WHICHEVER OCCURS LATER WITHIN 4,500 BEFORE 17,000 TOTAL FLIGHT CYCLES OR WITHIN 4,500 FLIGHT CYCLES AFTER THE FLIGHT CYCLES WITHIN 9,000 FLIGHT ORIGINAL ISSUE DATE BEFORE 17,000 AFTER THE CYCLES AFTER THE OF THIS SERVICE TOTAL FLIGHT CYCLES ORIGINAL ISSUE DATE OF THIS LAST OPEN HOLE HFEC INSPECTION WAS BULLETIN SERVICE DONE, WHICHEVER BULLETIN OCCURS LATER DO PART 1 CONDITION 1 CONDITION 2 NOT TO BEFORE FURTHER EXCEED 4,500 FLIGHT FLIGHT CYCLES CONDITION 2 (ACTION 1): CONTACT THE BOEING COMPANY FOR REPAIR REPEAT INSTRUCTIONS AND DO THE REPAIR PART 1 NOT TO EXCEED 4,500 FLIGHT CYCLES CONDITION 2 (ACTION 2): REPEAT PART 1 2536211 APPENDIX A: LOGIC DIAGRAM FOR PARAGRAPH 1.E. COMPLIANCE: TABLE 1: SURFACE HIGH FREQUENCY EDDY CURRENT (HFEC) INSPECTION OF THE UPPER AFT SKIN ON THE LEFT AND RIGHT WING FROM WING BUTTOCK LINE (WBL) 159 TO WBL 220 (SHEET 2 OF 2) Original Issue: January 16, 2017 Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished 737-57A1329 Work - See page 1 for details. 50 of 56 ### Page 51 This Appendix applies only to: Group 2, Configuration 2. Logic diagrams are provided as an aid only. Information contained in Paragraph 1.E., Compliance is the primary source for compliance times. Information contained in Paragraph 3.B., Work Instructions is the primary source for tasks required for compliance. 1. The table below gives the description for the parts and conditions called out in the logic diagrams. DescriptionTitle SURFACE HFEC, LFEC AND DETAILED INSPECTION FROM WBL 159 TO WBL 220 IN AREAS WITH AN EXTERNAL REPAIR. PART 2 NO CRACK FOUND IN THE EXTERNAL REPAIR AREA.CONDITION 3 ANY CRACK FOUND IN THE EXTERNAL REPAIR AREA.CONDITION 4 APPENDIX B: LOGIC DIAGRAM FOR PARAGRAPH 1.E. COMPLIANCE: TABLE 2: SURFACE HIGH FREQUENCY EDDY CURRENT (HFEC), LOW FREQUENCY EDDY CURRENT (LFEC) & DETAILED INSPECTION OF THE UPPER AFT SKIN AND EXTERNAL REPAIR ON THE LEFT OR RIGHT WING FROM WING BUTTOCK LINE (WBL) 159 TO WBL 220 (SHEET 1 OF 2) Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: January 16, 2017 737-57A1329 51 of 56 BOEING SERVICE BULLETIN 737-57A1329 ALERTALERT ### Page 52 (OCR) BOEING SERVICE BULLETIN 737-57A1329 ALERT ALERT ALL AIRPLANES WITH AN EXTERNAL REPAIR WHICHEVER OCCURS LATER BEFORE 17,000 TOTAL FLIGHT CYCLES OR WITHIN 9,000 FLIGHT CYCLES AFTER THE INSTALLATION OF THE EXTERNAL REPAIR, WHICHEVER OCCURS LATER WITHIN 2,000 FLIGHT CYCLES AFTER THE ORIGINAL ISSUE DATE OF THIS SERVICE BULLETIN DO PART 2 CONDITION 3 CONDITION 4 NOT TO EXCEED BEFORE FURTHER 2,000 FLIGHT FLIGHT CYCLES CONTACT THE BOEING COMPANY REPEAT FOR REPAIR INSTRUCTIONS AND PART 2 DO THE REPAIR 2536213 APPENDIX B: LOGIC DIAGRAM FOR PARAGRAPH 1.E. COMPLIANCE: TABLE 2: SURFACE HIGH FREQUENCY EDDY CURRENT (HFEC), LOW FREQUENCY EDDY CURRENT (LFEC) & DETAILED INSPECTION OF THE UPPER AFT SKIN AND EXTERNAL REPAIR ON THE LEFT OR RIGHT WING FROM WING BUTTOCK LINE (WBL) 159 TO WBL 220 (SHEET 2 OF 2) Original Issue: January 16, 2017 PROPRIETARY - Copyright © Unpublished Export Controlled ECCN: 9E991 - BOEING 737-57A1329 50 of 56 ### Page 53 This Appendix applies only to: Group 3. Logic diagrams are provided as an aid only. Information contained in Paragraph 1.E., Compliance is the primary source for compliance times. Information contained in Paragraph 3.B., Work Instructions is the primary source for tasks required for compliance. 1. The table below gives the description for the parts and conditions called out in the logic diagrams. DescriptionTitle SURFACE HFEC INSPECTION OF THE UPPER AFT SKIN FROM WBL 159 TO WBL 220 IN AREAS WITHOUT AN EXTERNAL REPAIR PART 1 NO CRACK FOUND IN THE UPPER AFT SKIN.CONDITION 1 ANY CRACK FOUND IN THE UPPER AFT SKIN.CONDITION 2 2. The table below gives the description for the flag notes called out in the logic diagram. DescriptionFlag Note Letter Accomplishment of an open hole HFEC inspection of the fastener holes common to the upper aft skin and strap aft of the rear spar in the inspection area is met if the inspection was done in accordance with 737 NDT Manual Part 6, 51-00-00 Procedure 1 or Procedure 16 during the accomplishment of Boeing ODA FAA Form 8100-9 approved upper rear spar chord replacement repair. (a) The inspection area is defined in FIGURE 1 and FIGURE 3. APPENDIX C: LOGIC DIAGRAM FOR PARAGRAPH 1.E. COMPLIANCE: TABLE 3: SURFACE HIGH FREQUENCY EDDY CURRENT (HFEC) INSPECTION OF THE UPPER AFT SKIN ON THE LEFT AND RIGHT WING FROM WING BUTTOCK LINE (WBL) 159 TO WBL 220 (SHEET 1 OF 2) Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: January 16, 2017 737-57A1329 53 of 56 BOEING SERVICE BULLETIN 737-57A1329 ALERTALERT ### Page 54 (OCR) BOEING SERVICE BULLETIN 737-57A1329 ALERT ALERT AIRPLANES THAT HAVE NOT DONE AN OPEN HOLE HFEC INSPECTION OF THE FASTENER HOLES COMMON TO THE UPPER AFT SKIN AND STRAP AFT OF THE REAR SPAR IN THE INSPECTION AREA (a) AIRPLANES THAT HAVE DONE AN OPEN HOLE HFEC INSPECTION OF THE FASTENER HOLES COMMON TO THE UPPER AFT SKIN AND STRAP AFT OF THE REAR SPAR IN THE INSPECTION AREA (a) WHICHEVER OCCURS LATER WHICHEVER OCCURS LATER BEFORE 14,000 TOTAL WITHIN 4,500 FLIGHT WITHIN 4,500 FLIGHT CYCLES FLIGHT CYCLES OR WITHIN 7,000 FLIGHT CYCLES AFTER THE ORIGINAL ISSUE DATE BEFORE 14,000 TOTAL FLIGHT AFTER THE ORIGINAL ISSUE CYCLES AFTER THE LAST OPEN HOLE HFEC BULLETIN OF THIS SERVICE CYCLES DATE OF THIS INSPECTION WAS SERVICE DONE, WHICHEVER BULLETIN OCCURS LATER DO PART 1 CONDITION 1 CONDITION 2 NOT TO BEFORE FURTHER EXCEED 4,500 FLIGHT FLIGHT CYCLES CONDITION 2 (ACTION 1): CONTACT THE BOEING COMPANY FOR REPAIR REPEAT INSTRUCTIONS AND DO THE REPAIR PART 1 NOT TO EXCEED 4,500 FLIGHT CYCLES CONDITION 2 (ACTION 2): REPEAT PART 1 2536214 APPENDIX C: LOGIC DIAGRAM FOR PARAGRAPH 1.E. COMPLIANCE: TABLE 3: SURFACE HIGH FREQUENCY EDDY CURRENT (HFEC) INSPECTION OF THE UPPER AFT SKIN ON THE LEFT AND RIGHT WING FROM WING BUTTOCK LINE (WBL) 159 TO WBL 220 (SHEET 2 OF 2) Original Issue: January 16, 2017 Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished 737-57A1329 Work - See page 1 for details. 54 of 56 ### Page 55 This Appendix applies only to: Group 3, Configuration 2. Logic diagrams are provided as an aid only. Information contained in Paragraph 1.E., Compliance is the primary source for compliance times. Information contained in Paragraph 3.B., Work Instructions is the primary source for tasks required for compliance. 1. The table below gives the description for the parts and conditions called out in the logic diagrams. DescriptionTitle SURFACE HFEC, LFEC AND DETAILED INSPECTION FROM WBL 159 TO WBL 220 IN AREAS WITH AN EXTERNAL REPAIR. PART 2 NO CRACK FOUND IN THE EXTERNAL REPAIR AREA.CONDITION 3 ANY CRACK FOUND IN THE EXTERNAL REPAIR AREA.CONDITION 4 APPENDIX D: LOGIC DIAGRAM FOR PARAGRAPH 1.E. COMPLIANCE: TABLE 4: SURFACE HIGH FREQUENCY EDDY CURRENT (HFEC), LOW FREQUENCY EDDY CURRENT (LFEC) & DETAILED INSPECTION OF THE UPPER AFT SKIN AND EXTERNAL REPAIR ON THE LEFT OR RIGHT WING FROM WING BUTTOCK LINE (WBL) 159 TO WBL 220 (SHEET 1 OF 2) Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: January 16, 2017 737-57A1329 55 of 56 BOEING SERVICE BULLETIN 737-57A1329 ALERTALERT ### Page 56 (OCR) BOEING SERVICE BULLETIN 737-57A1329 ALERT ALERT ALL AIRPLANES WITH AN EXTERNAL REPAIR WHICHEVER OCCURS LATER BEFORE 14,000 TOTAL FLIGHT CYCLES OR WITHIN 7,000 FLIGHT CYCLES AFTER THE INSTALLATION OF THE EXTERNAL REPAIR, WHICHEVER OCCURS LATER WITHIN 1,500 FLIGHT CYCLES AFTER THE ORIGINAL ISSUE DATE OF THIS SERVICE BULLETIN DO PART 2 CONDITION 3 CONDITION 4 NOT TO EXCEED BEFORE FURTHER 1,500 FLIGHT FLIGHT CYCLES CONTACT THE BOEING COMPANY REPEAT FOR REPAIR INSTRUCTIONS AND PART 2 DO THE REPAIR 2536216 APPENDIX D: LOGIC DIAGRAM FOR PARAGRAPH 1.E. COMPLIANCE: TABLE 4: SURFACE HIGH FREQUENCY EDDY CURRENT (HFEC), LOW FREQUENCY EDDY CURRENT (LFEC) & DETAILED INSPECTION OF THE UPPER AFT SKIN AND EXTERNAL REPAIR ON THE LEFT OR RIGHT WING FROM WING BUTTOCK LINE (WBL) 159 TO WBL 220 (SHEET 2 OF 2) Original Issue: January 16, 2017 PROPRIETARY - Copyright © Unpublished Export Controlled ECCN: 9E991 - BOEING 737-57A1329 56 of 56 --- 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.