### Commercial **Airplanes** 

# 747 Service Bulletin **ALERT Number: 747-53A2494**  Original Issue: September 18, 2003 Revision 1: January 09, 2015 ATA System: 5312 **SUBJECT:** FUSELAGE - Section 46 - Body Station 2231 Frame Inner Chord Crack Inspection and Repair Export of this technology is controlled under the United States Export Administration Regulations (EAR) (15 CFR 300-774). An export license may be required before it is used for development, production or use by foreign persons from specific countries. The controller of this data has the individual responsibility to abide by all export laws. 9E991 ECCN: 

## BOEING PROPRIETARY, CONFIDENTIAL AND/OR TRADE SECRET Copyright © 2003 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 Unpublished Work.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: September 18, 2003 747-53A2494 Revision 1: January 09, 2015 1 of 48 4.0Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: September 18, 2003 747-53A2494 Revision 1: January 09, 2015 2 of 48 **BOEING SERVICE BULLETIN 747-53A2494 ALERT**  **ALERT**

BLANK PAGE**Table of Contents** Revision Transmittal Sheet............................................ 5 Summary...................................................... 7 1. PLANNING INFORMATION. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11 A. Effectivity. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11 1. Airplanes. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11 2. Spares Affected. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20 B. Concurrent Requirements. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20 C. Reason. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20 D. Description. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21 E. Compliance. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22 F. Approval. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24 G. Manpower. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25 H. Weight and Balance Changes. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27 I. Electrical Load Data. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27 J. References. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27 1. Existing Data:. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27 2. Data Supplied with this Service Bulletin:. . . . . . . . . . . . . . . . . . . . . . . . . . . 27 3. Installation Drawings Used in the Preparation of this Service Bulletin:. . . . . . . . . . . 27 K. Publications Affected. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27 L. Interchangeability and Intermixability of Parts. . . . . . . . . . . . . . . . . . . . . . . . . . . 28 M. Software Accomplishment Summary. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28 2. MATERIAL INFORMATION. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29 A. Material - Price and Availability. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29 B. Industry Support Information. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29 C. Parts Necessary for Each Airplane. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29 1. Kits/Parts:. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29 2. Parts and Materials Supplied by the Operator:. . . . . . . . . . . . . . . . . . . . . . . . 29 3. Parts Modified and Reidentified:. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29 4. Parts Removed and Not Replaced:. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29 D. Parts Necessary to Change Spares. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29 E. Special Tooling - Price and Availability. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29 F. Special Tooling Necessary to do this Service Bulletin. . . . . . . . . . . . . . . . . . . . . . . 29 3. ACCOMPLISHMENT INSTRUCTIONS. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31 A. GENERAL INFORMATION. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31 B. WORK INSTRUCTIONS. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32 FIGURE 1: THIS FIGURE IS DELETED. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35 FIGURE 2: ACCESS / RESTORATION FOR CONFIGURATION WITH PASSENGERS IN THE AFT BODY [Group 1, 3]. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36 FIGURE 3: ACCESS / RESTORATION FOR CONFIGURATION WITH CARGO IN THE AFT BODY [Group 2, 4] . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 38 FIGURE 4: INSPECTION [Group 1-4, Configuration 1]. . . . . . . . . . . . . . . . . . . . . . . . . . 40 FIGURE 5: HFEC INSPECTION. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 43 APPENDIX A: LOGIC DIAGRAM [Group 1-4, Configuration 1]. . . . . . . . . . . . . . . . . . . . . . . . 46 APPENDIX B: LOGIC DIAGRAM [Group 1-4, Configuration 2]. . . . . . . . . . . . . . . . . . . . . . . . 48

Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: September 18, 2003 747-53A2494 Revision 1: January 09, 2015 3 of 48 **BOEING SERVICE BULLETIN 747-53A2494 ALERT**  **ALERT**Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: September 18, 2003 747-53A2494 Revision 1: January 09, 2015 4 of 48 **BOEING SERVICE BULLETIN 747-53A2494 ALERT**  **ALERT**

BLANK PAGE

### Commercial **Airplanes** 

# 747 Service Bulletin **ALERT Revision Transmittal Sheet**  **Number: 747-53A2494** Original Issue: September 18, 2003 Revision 1: January 09, 2015 ATA System: 5312 **SUBJECT:** FUSELAGE - Section 46 - Body Station 2231 Frame Inner Chord Crack Inspection and Repair This revision includes all pages of the service bulletin. **COMPLIANCE INFORMATION RELATED TO THIS REVISION** More work is necessary on the airplane(s) changed or inspected in accordance with the original issue of this service bulletin. Do HFEC initial inspection and repeat inspections in accordance with this revision. Airplanes RT631-RT632, RT743 and RT876, which have been modified to the 747 Large Cargo Freighter (LCF) configuration, have been removed from the effectivity of this service bulletin. Federal Aviation Administration (FAA) Airworthiness Directive AD 2005-01-09 is related to this service bulletin. **REASON FOR REVISION** This revision is sent to include HFEC initial inspection and repeat inspections for the Body Station (STA) 2231 Frame Inner Chord. This revision is also sent to include new SRM repairs. The inspections in this service bulletin are similar to the inspections in Boeing Service Bulletin 747-53A2450 R07, which begin before 16,000 total flight cycles. These sections were changed: 1. In the Background paragraph in the Summary section, changed to include new work, SRP references and planning data table. 2. In the Action paragraph in the Summary section, changed to include new work. 3. In the Effectivity paragraph in the Summary section, changed to better describe affected airplanes. 4. In the Compliance paragraph in the Summary section, updated to direct to Paragraph 1.E.. 5. Summary illustration updated to include new work. 6. In Paragraph 1.A., Effectivity, airplanes RT631, RT632, RT743, and RT876 have been removed from the effectivity, and Group configurations added to the table. 7. In Paragraph 1.C., Reason, changed to include new work and added new paragraphs describing the reason for revision.

Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: September 18, 2003 747-53A2494 Revision 1: January 09, 2015 5 of 488. In Paragraph 1.D., Description, updated work summary, added reason for revision and maintenance zone data. 9. In Paragraph 1.E., Compliance, added Airworthiness Directive statement and new compliance information in tabular format. 10. In Paragraph 1.F., Approval, updated approval statement and added new Airworthiness Directive statement. 11. In Paragraph 1.G., Manpower, added new manpower tables for repeat inspections. 12. In Paragraph 1.J., References, added new SRP and AD references. 13. In Paragraph 1.K., Publications Affected, a Damage Tolerance statement was added. 14. In Paragraph 2.B., Industry Support Information, revised the statement. 15. In Paragraph 3.B., Work Instructions, updated to include new general information and new inspections. 16. FIGURE 1 was deleted and Logic Diagram moved to Appendix A and Appendix B. 17. In FIGURE 2, added group information. 18. In FIGURE 3, added group information. 19. In FIGURE 4, added group information, changed sheet 2 and step table. 20. FIGURE 5 was added for HFEC Inspection. 21. APPENDIX A and APPENDIX B were added to include new Logic Diagrams. Vertical lines are put on the left edge of each page, except in Paragraph 1.A., Effectivity and format changes, to show the location of all content changes. Pages with no vertical lines have no changes. **REVISION HISTORY** September 18, 2003 Original Issue: January 09, 2015 Revision 1:

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### Commercial **Airplanes** 

# 747 Service Bulletin **ALERT Summary**  **Number: 747-53A2494** Original Issue: September 18, 2003 Revision 1: January 09, 2015 ATA System: 5312 **SUBJECT:** FUSELAGE - Section 46 - Body Station 2231 Frame Inner Chord Crack Inspection and Repair THIS BULLETIN IS SENT TO THE OPERATORS OF RECORD OF THE AIRPLANES SHOWN IN PARAGRAPH 1.A., EFFECTIVITY. IF AN AIRPLANE HAS BEEN LEASED OR SOLD, SEND THIS SERVICE BULLETIN TO THE NEW OPERATOR. IF APPLICABLE SPARES HAVE BEEN SOLD, SEND THIS SERVICE BULLETIN TO THE NEW OWNER. **CONCURRENT REQUIREMENTS** None. **BACKGROUND** Accomplishment of this service bulletin will make sure that the body frame at station 2231 at stringer 26 does not have any nicks, scratches, and / or gouges, and has no cracks. Cracks can initiate at nicks, scratches, and / or gouges. If not repaired, cracks could result in damage to the adjacent structure which could result in rapid depressurization of the airplane. The body frame at station 2231 is forward of the number 5 main entry door opening. The door 5 lower main sill goes through a cutout in the station 2231 frame at stringer 26. Boeing investigation indicates that during production, the door lower main sill chord can rub the station 2231 frame. If the sill rubs the frame, nicks, scratches, and / or gouges in the frame inner chord can occur which can cause frame cracks. Cracks in the inner chords and web at this location could extend with continued operation and fully cut the frame. If the frame becomes fully cut, skin cracks could occur which could cause a rapid depressurization of the airplane. One operator has reported cracked inner chords (forward and aft) and a cracked web at station 2231 and stringer 26L. Refer to Paragraph 1.C., Reason, for a detailed service history. Airplane line numbers 1334 and on were delivered with additional checks to ensure no nicks, scratches, and/or gouges were added during the production process. Inspections accomplished in accordance with Service Bulletin 747-53A2450 R07 are an acceptable substitute for the inspections specified in this service bulletin. Airplane line numbers 1-1419, except 747SP and 747-400 LCF, are affected by Service bulletin 747-53A2450 R07 . This table is provided to operators for planning purposes only. Refer to the applicable sections for more information.

Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: September 18, 2003 747-53A2494 Revision 1: January 09, 2015 7 of 48**Reference Affected**  **Planning Data** Paragraph 1.A.2., Spares Affected No Spares Affected Paragraph 1.E., Compliance and Paragraph 1.F., Approval Yes AD Related Paragraph 1.H., Weight and Balance Changes No Weight and Balance Change Paragraph 1.I., Electrical Load Data No Electrical Load Changed Paragraph 1.K., Publications Affected No Publications Affected Paragraph 1.K., Publications Affected No Airplane Flight Operations Affected (Flight CrewOperations Manual and/or FAA Approved Airplane Flight Manual) Paragraph 2.C.1., Kits/Parts No Kits/Parts Required Paragraph 2.C.2., Parts and Materials Supplied by the Operator No Operator Supplied Parts/Material Paragraph 2.F., Special Tooling Necessary to do this Service Bulletin No Special Tooling Required

Boeing Service Related Problems (SRP) 747-SRP-53-0202 and 747-SRP-53-0452 are related to this service bulletin. **ACTION** Do a detailed inspection for nicks, scratches, and / or gouges of the station 2231 frame inner chords (forward and aft), and web, at stringer 26 at the edge and side of the inner chords and do a surface High Frequency Eddy Current (HFEC) inspection of the Station 2231 frame inner chords (forward and aft), for cracks. If any nicks, scratches, and / or gouges are found, repair in accordance with the Structural Repair Manual (SRM) before next flight. If cracks are found do a repair in accordance with the SRM, or contact Boeing for repair instructions, before further flight. Repeat the HFEC inspection for cracks in accordance with Paragraph 1.E., Compliance. **EFFECTIVITY** 747-100, 747-100B, 747-100B SUD, 747-200B, 747-200C, 747-200F, 747-300, 747-400, 747-400D, 747-400F and 747SR Airplane(s). Refer to Paragraph 1.A.1., Airplanes, for the list of affected airplane(s). **COMPLIANCE** Refer to Paragraph 1.E., Compliance. **INDUSTRY SUPPORT INFORMATION** Boeing warranty remedies are available for airplanes in warranty as of November 22, 2002. Please refer to Paragraph 2.B., Industry Support Information. **MANPOWER Elapsed Hours**  **Total Task Hours Airplanes**  3 4 Groups 1 and 3

Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: September 18, 2003 747-53A2494 Revision 1: January 09, 2015 8 of 48 **BOEING SERVICE BULLETIN 747-53A2494 ALERT**  **ALERT Elapsed Hours**  **Total Task Hours Airplanes**  3 4 Groups 2 and 4 (with two MED #5) 1.5 2 Groups 2 and 4 (with one MED #5)
**MATERIAL INFORMATION** None.

Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: September 18, 2003 747-53A2494 Revision 1: January 09, 2015 9 of 48 **BOEING SERVICE BULLETIN 747-53A2494 ALERT**  **ALERT**Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: September 18, 2003 747-53A2494 Revision 1: January 09, 2015 10 of 48 **BOEING SERVICE BULLETIN 747-53A2494 ALERT**  **ALERT**

### Commercial **Airplanes** 

# 747 Service Bulletin **ALERT Number: 747-53A2494**  Original Issue: September 18, 2003 Revision 1: January 09, 2015 ATA System: 5312 **SUBJECT:** FUSELAGE - Section 46 - Body Station 2231 Frame Inner Chord Crack Inspection and Repair THIS BULLETIN IS SENT TO THE OPERATORS OF RECORD OF THE AIRPLANES SHOWN IN PARAGRAPH 1.A., EFFECTIVITY. IF AN AIRPLANE HAS BEEN LEASED OR SOLD, SEND THIS SERVICE BULLETIN TO THE NEW OPERATOR. IF APPLICABLE SPARES HAVE BEEN SOLD, SEND THIS SERVICE BULLETIN TO THE NEW OWNER. **1. PLANNING INFORMATION A. Effectivity**  1. Airplanes This service bulletin is applicable to 747-100, -100B, -100B SUD, -200B, -200C, -200F, -300, -400, -400D, -400F and 747SR Airplanes, line numbers 1-1333, except 747 Large Cargo Freighter (LCF) airplanes, in four Groups. The Variable Numbers and Group Information for the applicable airplanes is given below. Refer to Service Bulletin Index Document D6-30300 Part 3 for Airplane Variable Number, Line Number, and Serial Number data.
**DESCRIPTION CONFIGURATION**  **GROUP** 747-100, 747-100B, 747-100B SUD, 747-200B, 747-300, 747-400, 747-400D and 747SR airplanes, line number 1 through 1304, except Combi, Special Freighter, Boeing Converted Freighter (BCF) and 747 Large Cargo Freighter (LCF) airplanes. - 1

That have not completed the original issue of this service bulletin. 1 That have completed the original issue of this service bulletin. 2

Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: September 18, 2003 747-53A2494 Revision 1: January 09, 2015 11 of 48**DESCRIPTION CONFIGURATION**  **GROUP** 747-200B, 747-200C, 747-200F, 747-300, 747-400 and 747-400F Freighter, Convertible, Combi, Special Freighter, and BCF airplanes, line number 1 through 1304. - 2

That have not completed the original issue of this service bulletin. 1 That have completed the original issue of this service bulletin. 2 747-400 Passenger airplanes, from line number 1305 through 1333.

- 3 That have not completed the original issue of this service bulletin. 1 That have completed the original issue of this service bulletin 2 747-400F airplanes, from line number 1305 through 1333.

- 4 That have not completed the original issue of this service bulletin. 1 That have completed the original issue of this service bulletin 2

Airplane Models: 747-100, 747-100B, 747-100B SUD, 747-200B, 747-200C, 747-200F, 747-300, 747-400, 747-400D, 747-400F, 747SR **Group Variable Number**  1 RA001 - RA034 1 RA101 - RA115 1 RA161 - RA164 1 RA201 - RA203 1 RA216 - RA217 1 RA245 - RA246 1 RA251 - RA266 1 RA301 - RA318 1 RA351 - RA360 1 RA369 - RA373 1 RA401 - RA418 1 RA501 - RA502 1 RA521 - RA528 1 RA532 - RA548

Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: September 18, 2003 747-53A2494 Revision 1: January 09, 2015 12 of 48 **BOEING SERVICE BULLETIN 747-53A2494 ALERT**  **ALERT Group**  **Variable Number** 1 RA551 - RA552 1 RA559 - RA561 1 RA581 - RA582 1 RA585 1 RA601 - RA602 1 RA631 - RA635 1 RA651 - RA652 1 RA671 - RA677 1 RA701 - RA702 1 RA721 - RA731 1 RA741 - RA745 2 RA749 - RA750 1 RA761 - RA762 1 RA781 - RA784 1 RA901 - RA916 1 RB001 - RB016 1 RB041 - RB044 1 RB071 - RB075 1 RB101 - RB102 2 RB411 - RB413 2 RB421 1 RB601 - RB607 1 RB681 - RB697 1 RB711 1 RB721 - RB723 1 RB741 - RB748 1 RD001 - RD004 1 RD021 - RD022 1 RD041 - RD059 1 RD071 - RD072 1 RD081 - RD083 1 RD091 - RD092 1 RD101 - RD104

Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: September 18, 2003 747-53A2494 Revision 1: January 09, 2015 13 of 48 **BOEING SERVICE BULLETIN 747-53A2494 ALERT**  **ALERT Group**  **Variable Number** 1 RD121 - RD127 1 RD131 - RD144 1 RD166 - RD167 1 RD171 - RD172 1 RD181 - RD183 2 RD201 - RD204 1 RD221 - RD227 1 RD231 - RD235 1 RD241 - RD243 1 RD251 - RD262 1 RD271 - RD272 1 RD291 - RD292 1 RD301 - RD302 1 RD311 1 RD351 - RD358 1 RD361 - RD366 1 RD381 - RD383 1 RD411 - RD414 1 RD421 - RD426 1 RD431 - RD435 1 RD441 - RD442 1 RD451 - RD456 1 RD461 1 RD471 - RD475 1 RD513 - RD519 2 RD531 - RD533 2 RD551 2 RD561 2 RD571 2 RD581 - RD583 2 RD591 - RD593 2 RD601 - RD607 2 RD621 - RD623

Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: September 18, 2003 747-53A2494 Revision 1: January 09, 2015 14 of 48 **BOEING SERVICE BULLETIN 747-53A2494 ALERT**  **ALERT Group**  **Variable Number** 2 RD641 - RD649 2 RD651 - RD659 2 RD661 2 RD671 2 RD681 - RD682 2 RD691 - RD692 2 RD701 - RD702 2 RD721 - RD722 2 RD741 - RD742 2 RD751 - RD755 2 RD761 2 RD771 - RD775 2 RD781 - RD783 2 RD791 - RD792 1 RE001 3 RF001 - RF006 2 RJ131 - RJ133 2 RJ151 - RJ152 2 RJ301 - RJ303 2 RJ321 - RJ322 2 RJ331 - RJ333 2 RL401 - RL402 4 RL403 2 RL411 - RL419 4 RL420 - RL421 4 RL431 - RL432 2 RL651 - RL654 4 RL655 4 RL671 - RL673 4 RL681 - RL682 4 RL751 - RL752 1 RM001 - RM007 1 RM010 - RM013

Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: September 18, 2003 747-53A2494 Revision 1: January 09, 2015 15 of 48 **BOEING SERVICE BULLETIN 747-53A2494 ALERT**  **ALERT Group**  **Variable Number** 1 RM021 - RM024 1 RM026 - RM029 1 RM036 - RM045 1 RM051 - RM052 1 RM071 1 RM081 - RM084 1 RM091 1 RM096 - RM097 1 RM116 - RM117 1 RM126 - RM132 1 RM136 - RM147 1 RM156 - RM158 1 RM166 - RM177 1 RM191 - RM192 1 RM231 - RM233 1 RM241 - RM246 1 RM261 - RM264 1 RM316 - RM318 1 RM331 - RM333 1 RM341 1 RM351 - RM355 1 RM366 - RM367 3 RM401 - RM402 3 RM426 2 RM801 - RM803 2 RM811 - RM813 2 RM851 - RM858 2 RM861 4 RM862 2 RM871 - RM876 4 RM877 - RM879 2 RM881 - RM886 4 RM887

Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: September 18, 2003 747-53A2494 Revision 1: January 09, 2015 16 of 48 **BOEING SERVICE BULLETIN 747-53A2494 ALERT**  **ALERT Group**  **Variable Number** 2 RM891 - RM899 2 RM901 - RM904 4 RM905 - RM906 2 RM911 2 RR001 - RR005 2 RR021 - RR025 2 RR031 2 RR201 - RR206 2 RR221 - RR226 2 RR261 - RR267 2 RR301 - RR310 2 RR331 - RR332 2 RR336 2 RR341 - RR345 2 RR361 - RR362 2 RR421 - RR422 2 RR431 - RR432 2 RR441 - RR442 2 RR451 2 RR501 - RR504 2 RR521 - RR522 2 RR526 2 RR531 2 RR551 - RR556 2 RR561 2 RR566 2 RR701 2 RR721 - RR724 2 RR746 - RR748 2 RR851 - RR856 2 RR861 - RR862 2 RR951 - RR952 1 RS001 - RS002

Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: September 18, 2003 747-53A2494 Revision 1: January 09, 2015 17 of 48 **BOEING SERVICE BULLETIN 747-53A2494 ALERT**  **ALERT Group**  **Variable Number** 1 RS201 1 RS211 - RS212 1 RS221 - RS222 1 RS231 - RS241 1 RS251 - RS259 1 RS263 1 RS265 - RS268 1 RS271 - RS276 1 RS291 - RS292 1 RS301 - RS306 1 RS311 - RS320 1 RS331 - RS333 1 RS341 - RS342 1 RS699 2 RS701 - RS703 2 RS711 - RS713 2 RS721 - RS722 2 RS731 - RS732 2 RS741 - RS743 2 RS751 - RS752 2 RS761 - RS762 2 RS771 2 RS781 - RS782 2 RS786 2 RT001 - RT014 2 RT021 - RT022 2 RT031 - RT035 2 RT041 - RT047 2 RT061 2 RT071 - RT075 2 RT101 - RT103 2 RT121 2 RT131 - RT137

Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: September 18, 2003 747-53A2494 Revision 1: January 09, 2015 18 of 48 **BOEING SERVICE BULLETIN 747-53A2494 ALERT**  **ALERT Group**  **Variable Number** 2 RT151 - RT152 2 RT161 - RT168 1 RT401 - RT412 1 RT431 - RT447 1 RT451 - RT469 1 RT471 - RT499 1 RT501 - RT535 1 RT551 - RT568 1 RT571 - RT591 1 RT601 - RT630 1 RT633 - RT657 1 RT671 - RT673 1 RT681 - RT682 1 RT691 - RT699 1 RT701 - RT704 1 RT711 - RT717 1 RT741 - RT742 1 RT744 - RT757 1 RT776 - RT777 1 RT781 - RT784 1 RT801 - RT803 1 RT811 - RT814 1 RT831 - RT837 1 RT861 - RT864 1 RT877 - RT880 1 RT931 - RT932 1 RT945 - RT949 1 RT951 - RT955 1 RT966 - RT967 1 RU001 - RU006 1 RU016 - RU017 1 RU031 - RU032 1 RU051 - RU052

Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: September 18, 2003 747-53A2494 Revision 1: January 09, 2015 19 of 48 **BOEING SERVICE BULLETIN 747-53A2494 ALERT**  **ALERT Group**  **Variable Number** 1 RU059 - RU062 1 RU081 - RU083 1 RU101 - RU102 1 RU121 - RU132 1 RU801 - RU809 1 RU831 - RU841 2. Spares Affected None. **B. Concurrent Requirements** None. **C. Reason** Accomplishment of this service bulletin will make sure that the body frame at station 2231 at stringer 26 does not have any nicks, scratches, and / or gouges, and has no cracks. Cracks can initiate at nicks, scratches, and / or gouges. If not repaired, cracks could result in damage to the adjacent structure which could result in rapid depressurization of the airplane. The body frame at station 2231 is forward of the number 5 main entry door opening. The door 5 lower main sill goes through a cutout in the station 2231 frame at stringer 26. Boeing investigation indicates that during production, the door lower main sill chord can rub the station 2231 frame. If the sill rubs the frame, nicks, scratches, and / or gouges in the frame inner chord can occur which can cause frame cracks. Cracks in the inner chords and web at this location could extend with continued operation and fully cut the frame. If the frame becomes fully cut, skin cracks could occur which could cause a rapid depressurization of the airplane. One operator has reported cracked inner chords (forward and aft) and a cracked web at station 2231 and stringer 26L. The following table provides service history details. **Service History Report**  **Cycles / Hours** Both chords and web severed on BS 2231 Frame at Stringer 26L 14,687 / 87,877

Between the release of the original issue and Revision 1 of this service bulletin, there have been further reports of cracking in the inner chords at station 2231 and stringer 26 (left and right). The crack at this location is also inspected in accordance with 747-53A2450 R07, which must begin before 16,000 flight cycles. The following table provides the service history details of one of the reports provided between the original issue and Revision 1.

Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: September 18, 2003 747-53A2494 Revision 1: January 09, 2015 20 of 48 **BOEING SERVICE BULLETIN 747-53A2494 ALERT**  **ALERT Service History**  **Report Cycles / Hours**  0.25" crack on BS 2231 Frame inner chord at Stringer 26R 11,023 / 91,788

Airplane line numbers 1334 and on were delivered with additional checks to ensure no nicks, scratches, and/or gouges were added during the production process. Inspections accomplished in accordance with Service Bulletin 747-53A2450 Revision 7 are similar to the inspections specified in this service bulletin. Airplane line numbers 1-1419, except 747SP and 747-400LCF, are affected by Service bulletin 747-53A2450 R07. Revision 1 is sent to add a repeat surface High Frequency Eddy Current (HFEC) inspection of the Station 2231 frame inner chord. Boeing Service Related Problems (SRP) 747-SRP-53-0202 and 747-SRP-53-0452 are related to this service bulletin. **D. Description** Do a detailed inspection for nicks, scratches, and / or gouges of the station 2231 frame inner chords (forward and aft) at stringer 26 at the edge and side of the inner chords and do a surface High Frequency Eddy Current (HFEC) inspection of the frame inner chords (forward and aft) for cracks. If any nicks, scratches, and / or gouges are found, repair in accordance with the Structural Repair Manual (SRM) before next flight. If cracks are found do a repair in accordance with the SRM, or contact Boeing for repair instructions, before further flight. Repeat the HFEC inspection for cracks in accordance with Paragraph 1.E., Compliance. The airplane effectivity is divided into four groups because of access requirements. Revision 1 - More work is necessary on airplanes changed or inspected in accordance with the original issue of this service bulletin. Do HFEC initial inspection and repeat inspections in accordance with this revision. The work in this service bulletin is done in the maintenance zone(s) given below. **Group 1:**
**Affected Maintenance Zones Zone**  **Model** 271, 272 747-100, 747-100B, 747-100B SUD, 747-200B, 747-300, 747- 400, 747-400D, 747SR

Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: September 18, 2003 747-53A2494 Revision 1: January 09, 2015 21 of 48 **BOEING SERVICE BULLETIN 747-53A2494 ALERT**  **ALERT Group 2:** 
**Affected Maintenance Zones Zone**  **Model** 271, 272 747-200B, 747-200C, 747-200F, 747-300, 747-400, 747-400F **Group 3:**
**Affected Maintenance Zones Zone**  **Model** 271, 272 747-400 **Group 4:**
**Affected Maintenance Zones Zone**  **Model** 271, 272 747-400F **E. Compliance** Federal Aviation Administration (FAA) Airworthiness Directive 2005-01-09 is related to this service bulletin. The effective date of AD 2005-01-09 is February 11, 2005. **Group 1-4, Configuration 1: Table 1: Station 2231 Frame Inner Chord - Detailed and HFEC Inspections**  **Repeat Interval (Not to Exceed)**  **Compliance Time (Whichever Occurs Later)**  **Action Condition** 

- Within 1,500 flight cyclesafter the effective date of AD 2005- 01-09. Before 10,000 total flight cyclesDo a detailed inspection for nicks, scratches, or gouges of the frame inner chords and web in accordance with Paragraph 3.B., Work Instructions, Step 3 (a) All airplanes.

AND

- Within 1,500 flight cyclesafter the release of Revision 1 of thisservice bulletin. Before 10,000 total flight cycles.Do a surface HFEC inspection of the frame inner chords for cracks in accordance with Paragraph 3.B., Work Instructions, Step 4. (a)

Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: September 18, 2003 747-53A2494 Revision 1: January 09, 2015 22 of 48 **BOEING SERVICE BULLETIN 747-53A2494 ALERT**  **ALERT Group 1-4, Configuration 1:**  **Table 1: Station 2231 Frame Inner Chord - Detailed and HFEC Inspections Repeat Interval**  **(Not to Exceed) Compliance Time**  **(Whichever Occurs Later) Action**  **Condition**

- - Before fur- ther flight. Repair in accordance with Paragraph 3.B., Work Instructions, Step 5 Nicks, scratches or gouges found and no cracks found.

AND 3,000 flight cycles. - - Repeat the surface HFEC inspection of the frame inner chords for cracks in accordance with Paragraph 3.B., Work Instructions, Step 11. (a)

- - Before fur- ther flight. Repair in accordance with Paragraph 3.B., Work Instructions, Step 7 Any crack found.

AND 3,000 flight cycles. - - Repeat the surface HFEC inspection of the frame inner chords for cracks in accordance with Paragraph 3.B., Work Instructions, Step 11. (b) 3,000 flight cycles. - - Repeat the surface HFEC inspection of the frame inner chords for cracks in accordance with Paragraph 3.B., Work Instructions, Step 11. (a) No nicks, scratches or gouges found and no cracks found.

(a) Inspections accomplished in accordance with Service Bulletin 747-53A2450 Revision 7 are similar to the inspections specified in this service bulletin.(b) For airplanes with inner chords repaired in accordance with Paragraph 3.B., Work Instructions Step 7, do the inspections in accordance with Paragraph 3.B., Work Instructions Step 11 for the chords that were not repaired.

Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: September 18, 2003 747-53A2494 Revision 1: January 09, 2015 23 of 48 **BOEING SERVICE BULLETIN 747-53A2494 ALERT**  **ALERT Group 1-4, Configuration 2:**  **Table 2: Station 2231 Frame Inner Chord - HFEC Inspections Repeat Interval**  **(Not to Exceed) Compliance Time (Whichever**  **Occurs Later) Action**  **Condition**

- Within 1,500flight cycles after the release of Revision 1 ofthis service bulletin. Before 10,000total flight cycles.Do the surface HFEC inspection of the frame inner chords for cracks inaccordance with Paragraph 3.B., Work Instructions, Step 6. (a) All airplanes.

- Before further flight. Repair in accordance withParagraph 3.B., Work Instructions, Step 7. Any crack found.

AND 3,000 flight cycles.

- - Repeat the surface HFEC inspection of the frame inner chords for cracks inaccordance with Paragraph 3.B., Work Instructions, Step 11. (b) 3,000 flight cycles.

- - Repeat the surface HFEC inspection of the frame inner chords for cracks inaccordance with Paragraph 3.B., Work Instructions, Step 11. (a) No crack found.

(a) Inspections accomplished in accordance with Service Bulletin 747-53A2450 Revision 7 are similar to the inspections specified in this service bulletin. (b) For airplanes with inner chords repaired in accordance with Paragraph 3.B., Work Instructions Step 7, do the inspections in accordance with Paragraph 3.B., Work Instructions Step 11 for the chords that were not repaired. Logic diagrams showing compliance tasks and compliance times are included as an aid in Appendix A and B. **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.

Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: September 18, 2003 747-53A2494 Revision 1: January 09, 2015 24 of 48 **BOEING SERVICE BULLETIN 747-53A2494 ALERT**  **ALERT**The Manager of the FAA Seattle ACO approves the accomplishment of the inspection as defined by Boeing SB 747-53A2494 Revision 1 as an AMOC to the accomplishment of the inspection as defined by Boeing SB 747-53A2494 Original Issue required by paragraph (f) and (h) of AD 2005-01-09. All provisions of AD 2005-01-09 that are not specifically referenced in the above statement remain fully applicable and must be complied with accordingly. **G. Manpower** The tables below show estimates 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 examine the work — Time to cure the materials — Time to make the parts — Time to find the tools.
**GROUP 1 AND GROUP 3 AIRPLANES: Elapsed Hours**  **Task-Hours Number of Per-**  **sons Task** 

1 1 1 Open Access 1 2 2 Inspection 1 1 1 Close Access 3 4 TOTAL FOR EACH AIRPLANE (a) (a) Additional time may be required if repairs are accomplished.

**GROUP 2 AND GROUP 4 AIRPLANES WITH ACTIVE OR INACTIVE MAIN ENTRY DOOR 5 ON BOTH SIDES OF THE AIRPLANE:** **Elapsed Hours Task-Hours**  **Number of Per- sons**  **Task**

1 1 1 Open Access 1 2 2 Inspection 1 1 1 Close Access 3 4 TOTAL FOR EACH AIRPLANE (a) (a) Additional time may be required if repairs are accomplished.

Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: September 18, 2003 747-53A2494 Revision 1: January 09, 2015 25 of 48 **BOEING SERVICE BULLETIN 747-53A2494 ALERT**  **ALERT GROUP 2 AND GROUP 4 AIRPLANES WITH ACTIVE OR INACTIVE MAIN**  **ENTRY DOOR 5 ON ONE SIDE OF THE AIRPLANE: Elapsed Hours**  **Task-Hours Number of Per-**  **sons Task** 

.5 .5 1 Open Access .5 1 2 Inspection .5 .5 1 Close Access 1.5 2 TOTAL FOR EACH AIRPLANE (a) (a) Additional time may be required if repairs are accomplished.

**GROUP 1 AND GROUP 3 AIRPLANES: Elapsed Hours**  **Task-Hours Number of Per-**  **sons Task** 

1 1 1 Open Access 1 2 2 Repeat Inspection 1 1 1 Close Access 3 4 TOTAL FOR EACH AIRPLANE (a) (a) Additional time may be required if repairs are accomplished.

**GROUP 2 AND GROUP 4 AIRPLANES WITH ACTIVE OR INACTIVE MAIN ENTRY DOOR 5 ON BOTH SIDES OF THE AIRPLANE:** **Elapsed Hours Task-Hours**  **Number of Per- sons**  **Task**

1 1 1 Open Access 1 2 2 Repeat Inspection 1 1 1 Close Access 3 4 TOTAL FOR EACH AIRPLANE (a) (a) Additional time may be required if repairs are accomplished.

**GROUP 2 AND GROUP 4 AIRPLANES WITH ACTIVE OR INACTIVE MAIN ENTRY DOOR 5 ON ONE SIDE OF THE AIRPLANE:**  **Elapsed Hours Task-Hours**  **Number of Per- sons**  **Task**

.5 .5 1 Open Access .5 1 2 Repeat Inspection .5 .5 1 Close Access 1.5 2 TOTAL FOR EACH AIRPLANE (a) (a) Additional time may be required if repairs are accomplished.

Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: September 18, 2003 747-53A2494 Revision 1: January 09, 2015 26 of 48 **BOEING SERVICE BULLETIN 747-53A2494 ALERT**  **ALERT H. Weight and Balance Changes**  None. **I. Electrical Load Data** Not changed. **J. References** 1. Existing Data: a. Service Related Problem (SRP) 747-SRP-53-0202 b. Service Related Problem (SRP) 747-SRP-53-0452 c. 747-100/-200/-300 Maintenance Manual (AMM) Subjects 25-21-03, 25-21-04, 25-59-05 d. 747-400 Maintenance Manual (AMM) Subjects 25-21-03, 25-21-04 e. 747-100/-200/-300 Structural Repair Manual (SRM) Subjects 51-10-01, 53-10-04 Figure 147 f. 747-400 Structural Repair Manual (SRM) Subjects 51-10-00, 53-60-07 Repair 7 g. 747-400F Structural Repair Manual (SRM) Subject 53-60-07 Repair 7 h. 747-400SF Structural Repair Manual (SRM) Subject 53-60-07 Repair 7 i. 747 Nondestructive Test (NDT) Manual D6-7170, Part 6, Subject 51-00-00 j. Boeing Service Bulletin 747-53-2450 k. Federal Aviation Administration (FAA) Airworthiness Directive (AD) 2005-01-09, 2013-17-08 2. Data Supplied with this Service Bulletin: None. 3. Installation Drawings Used in the Preparation of this Service Bulletin: None. **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.

Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: September 18, 2003 747-53A2494 Revision 1: January 09, 2015 27 of 48 **BOEING SERVICE BULLETIN 747-53A2494 ALERT**  **ALERT 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: September 18, 2003 747-53A2494 Revision 1: January 09, 2015 28 of 48 **BOEING SERVICE BULLETIN 747-53A2494 ALERT**  **ALERT 2. MATERIAL INFORMATION**  **A. Material - Price and Availability** None. **B. Industry Support Information** Boeing warranty remedies are available for the original issue Service Bulletin work statement for 747 airplanes in warranty as of November 22, 2002. For inspection man-hour reimbursement for airplanes in warranty as of that date, send a warranty claim to BCA Fleet Support Contracts - Warranty. If the condition described in this service bulletin is found during inspection for airplanes in warranty as of that date and additional man hours are required, send a warranty claim to BCA Fleet Support Contracts - Warranty. Please refer to this service bulletin number and reference the airplane variable numbers in your purchase order. Boeing warranty remedies are not available for the additional work statement described in Revision 1 of 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: September 18, 2003 747-53A2494 Revision 1: January 09, 2015 29 of 48 **BOEING SERVICE BULLETIN 747-53A2494 ALERT**  **ALERT**Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: September 18, 2003 747-53A2494 Revision 1: January 09, 2015 30 of 48 **BOEING SERVICE BULLETIN 747-53A2494 ALERT**  **ALERT**

BLANK PAGE**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 747 Structural Repair Manual, Chapter 51. — Values for airframe maintenance tasks are included in Chapter 20 of 747 Airplane 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 747 Airplane 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. 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. 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.

Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: September 18, 2003 747-53A2494 Revision 1: January 09, 2015 31 of 48 **BOEING SERVICE BULLETIN 747-53A2494 ALERT**  **ALERT**7. Boeing Service Letter 747-SL-51-048, 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 and B 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. 9. The instructions in Paragraph 3.B., Work Instructions and the figures can include operation of tools or test equipment. Boeing Engineering Tool Drawings, the Illustrated Tool and Equipment Manual, and the Special Tool and Ground Handling Drawing Index contain data on versions of the tools or test equipment that you can use. It is permitted to use replaced tools. It is not permitted to use superseded tools. 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. Where the work instructions include installation of a kept part, a new or serviceable part with the same part number can be installed as an alternative to the kept part. 12. The compliance times for the actions in Paragraph 3.B., WORK INSTRUCTIONS are in Paragraph 1.E., Compliance. 13. Refinish bare metal areas to match surrounding area. **B. WORK INSTRUCTIONS** 1. Airplanes configured to carry passengers in the aft body should use FIGURE 2 for access. 2. Airplanes configured to carry cargo in the aft body should use FIGURE 3 for access. 3. **Group 1-4, Configuration 1:** Do a detailed inspection of the Station 2231 Frame Inner Chord (forward and aft) surfaces and edge and web edge for nicks, scratches, or gouges in accordance with FIGURE 4.
4. **Group 1-4, Configuration 1:** Do a surface High Frequency Eddy Current (HFEC) inspection on the Station 2231 Frame Inner Chord (forward and aft) surfaces for cracks in accordance with Figure 4.
5. **Group 1-4, Configuration 1:** If any nicks, scratches, or gouges are found and no cracks were found in accordance with Step 4, repair as follows: a. Rework in accordance with 747-100/-200/-300 SRM Section 51-10-01 (747-400 SRM 51-10-02, 747-400F SRM 51-10-02, 747-400SF SRM 51-10-02). b. Get a surface finish of 63 micro-inches or better. Break sharp edges. c. Maintain a minimum 2D edge margin to adjacent fastener locations.

Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: September 18, 2003 747-53A2494 Revision 1: January 09, 2015 32 of 48 **BOEING SERVICE BULLETIN 747-53A2494 ALERT**  **ALERT**d. Maintain a minimum rework radius of 0.30 inch.

e. **Group 1-2, Configuration 1:** Measure minimum distance "A" from the outboard edge of the chord flange to the rework radius as shown in FIGURE 4. Minimum acceptable dimension is: 0.625 inch If rework results in less than this dimension, contact Boeing for repair instructions and do the repair. f. **Group 3-4, Configuration 1:** Measure minimum distance "A" from the outboard edge of the chord flange to the rework radius as shown in FIGURE 4. Minimum acceptable dimension is: 0.510 inch If rework results in less than this dimension, contact Boeing for repair instructions and do the repair. g. Accomplish a surface High Frequency Eddy Current (HFEC) inspection of the reworked edge to ensure a crack free condition. Inspect in accordance with Nondestructive Test (NDT) Manual D6-7170, Part 6, Subject 51-00-00, Procedure 4 or 23. 6. **Group 1-4, Configuration 2:** Do a surface HFEC inspection on the Station 2231 Frame Inner Chord (forward and aft) surfaces for cracks in accordance with FIGURE 5. 7. If any crack is found, repair in accordance with 747-100/200/300 SRM 53-10-04 (Figure 147), 747-400 SRM 53-60-07 (Repair 7), 747-400F SRM 53-60-07 (Repair 7), 747-400SF SRM 53-60-07 (Repair 7), or contact Boeing for repair instructions and do the repair. **NOTE:**After the repair, it will be necessary to do inspections of the repaired area of the frame in accordance with 747-100/200/300 SRM 53-10-04 (Figure 147), 747-400 SRM 53-60-07 (Repair 7), 747-400F SRM 53-60-07 (Repair 7), 747-400SF SRM 53-60-07 (Repair 7), as applicable. If only one of the aft or forward inner chords is repaired, repeat the inspections in accordance with Step 11 for the chords that are not repaired. 8. Airplanes configured to carry passengers in the aft body should use FIGURE 2 for restoration. 9. Airplanes configured to carry cargo in the aft body should use FIGURE 3 for restoration. 10. Put the airplane back to a serviceable condition. 11. Do a repeat surface High Frequency Eddy Current (HFEC) inspection on the Station 2231 Frame Inner Chord (forward and aft) surfaces for cracks in accordance with FIGURE 5. If any crack is found, repair in accordance with 747-100/200/300 SRM 53-10-04 (Figure 147), 747-400 SRM 53-60-07 (Repair 7), 747-400F SRM 53-60-07 (Repair 7), 747-400SF SRM 53-60-07 (Repair 7), or contact Boeing for repair instructions and do the repair.

Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: September 18, 2003 747-53A2494 Revision 1: January 09, 2015 33 of 48 **BOEING SERVICE BULLETIN 747-53A2494 ALERT**  **ALERT NOTE:** After the repair, it will be necessary to do inspections of the repaired area of the frame in accordance with 747-100/200/300 SRM 53-10-04 (Figure 147), 747-400 SRM 53-60-07 (Repair 7), 747-400F SRM 53-60-07 (Repair 7), 747-400SF SRM 53-60-07 (Repair 7), as applicable. If only one of the aft or forward inner chords is repaired, repeat the inspections in accordance with Step 11 for the chords that are not repaired.

Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: September 18, 2003 747-53A2494 Revision 1: January 09, 2015 34 of 48 **BOEING SERVICE BULLETIN 747-53A2494 ALERT**  **ALERT FIGURE 1: THIS FIGURE IS DELETED**  **(SHEET 1 OF 1)** Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: September 18, 2003 747-53A2494 Revision 1 January 09, 2015 35 of 48 **BOEING SERVICE BULLETIN 747-53A2494 ALERT**  **ALERT This Figure applies only to: Group 1, 3.** 

**FIGURE 2: ACCESS / RESTORATION FOR CONFIGURATION WITH PASSENGERS IN THE AFT BODY (SHEET 1 OF 2)**  Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: September 18, 2003 747-53A2494 Revision 1 January 09, 2015 36 of 48 **BOEING SERVICE BULLETIN 747-53A2494 ALERT**  **ALERT**The step numbers shown below agree with the numbers shown in the circle symbols in the figure. The QTY numbers shown below are the number of parts necessary for one side of the airplane.
**NOTES QTY**  **REFERENCES NAME**  **TASK STEP** 

- 1 747 AMM 25-21-03, 747- 400 AMM 25-21-03 Lower transition Panel Remove 1 (a)

- 747 AMM 25-59-05, 747 AMM 25-21-04, 747-400 AMM 25-21-04 Insulation Blankets Pull Back 2

(a) Pull back insulation blankets in area of inspection. Insulation blankets not shown in figure.

**NOTES QTY**  **REFERENCES NAME**  **TASK STEP** 

- - 747 AMM 25-59-05, 747 AMM 25-21-04, 747-400 AMM 25-21-04 Insulation Blankets Install 3

- 1 747 AMM 25-21-03, 747- 400 AMM 25-21-03 Lower transition Panel Install 4

**FIGURE 2: ACCESS / RESTORATION FOR CONFIGURATION WITH PASSENGERS IN THE AFT BODY (SHEET 2 OF 2)**  Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: September 18, 2003 747-53A2494 Revision 1 January 09, 2015 37 of 48 **BOEING SERVICE BULLETIN 747-53A2494 ALERT**  **ALERT This Figure applies only to: Group 2, 4.** 

**FIGURE 3: ACCESS / RESTORATION FOR CONFIGURATION WITH CARGO IN THE AFT BODY (SHEET 1 OF 2)**  Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: September 18, 2003 747-53A2494 Revision 1 January 09, 2015 38 of 48 **BOEING SERVICE BULLETIN 747-53A2494 ALERT**  **ALERT**The step numbers shown below agree with the numbers shown in the circle symbols in the figure. The QTY numbers shown below are the number of parts necessary for one side of the airplane.
**NOTES QTY**  **REFERENCES NAME**  **TASK STEP** 

- 1 747 AMM 25-59-01, 747- 400 AMM 25-59-01 Lower transition Panel Remove 1 (a)

- 747 AMM 25-59-05, 747- 400 AMM 25-59-05 Insulation Blankets Pull Back 2 (a) Pull back insulation blankets in area of inspection. Insulation blankets not shown in figure.

**NOTES QTY**  **REFERENCES NAME**  **TASK STEP** 

- - 747 AMM 25-59-05, 747- 400 AMM 25-59-05 Insulation Blankets Install 3

- 1 747 AMM 25-59-01, 747- 400 AMM 25-59-01 Lower transition Panel Install 4

**FIGURE 3: ACCESS / RESTORATION FOR CONFIGURATION WITH CARGO IN THE AFT BODY (SHEET 2 OF 2)**  Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: September 18, 2003 747-53A2494 Revision 1 January 09, 2015 39 of 48 **BOEING SERVICE BULLETIN 747-53A2494 ALERT**  **ALERT This Figure applies only to: Group 1-4, Configuration 1.** 

**FIGURE 4: INSPECTION (SHEET 1 OF 3)**  Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: September 18, 2003 747-53A2494 Revision 1 January 09, 2015 40 of 48 **BOEING SERVICE BULLETIN 747-53A2494 ALERT**  **ALERT FIGURE 4: INSPECTION**  **(SHEET 2 OF 3)** Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: September 18, 2003 747-53A2494 Revision 1 January 09, 2015 41 of 48 **BOEING SERVICE BULLETIN 747-53A2494 ALERT**  **ALERT**The step numbers shown below agree with the numbers shown in the circle symbols in the figure.
**NOTES REFERENCES**  **PROCEDURE NAME**  **TASK STEP**  (a)

- Detailed Inspection Station 2231 Frame Inner Chords (surfaces and edge) and Web Edge Inspect 1

(b) 747 Nondestructive Test (NDT) Manual D6-7170, Part 6, Subject 51-00-00, Procedure 4 or 23Surface High Frequency Eddy Current (HFEC) Inspection Station 2231 Frame Inner Chords (surfaces) Inspect 2

(a) Do a detailed inspection of the Station 2231 Frame Inner Chords (forward and aft surfaces and edge) and Web edge for nicks, scratches, and / or gouges.(b) Do a surface HFEC inspection on the Station 2231 Frame Inner Chords (forward and aft surfaces) for cracks.

**FIGURE 4: INSPECTION (SHEET 3 OF 3)**  Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: September 18, 2003 747-53A2494 Revision 1 January 09, 2015 42 of 48 **BOEING SERVICE BULLETIN 747-53A2494 ALERT**  **ALERT FIGURE 5: HFEC INSPECTION**  **(SHEET 1 OF 3)** Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: September 18, 2003 747-53A2494 Revision 1 January 09, 2015 43 of 48 **BOEING SERVICE BULLETIN 747-53A2494 ALERT**  **ALERT FIGURE 5: HFEC INSPECTION**  **(SHEET 2 OF 3)** Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: September 18, 2003 747-53A2494 Revision 1 January 09, 2015 44 of 48 **BOEING SERVICE BULLETIN 747-53A2494 ALERT**  **ALERT**The step numbers shown below agree with the numbers shown in the circle symbols in the figure.
**NOTES REFERENCES**  **PROCEDURE NAME**  **TASK STEP**  (a) 747 Nondestructive Test (NDT) Manual D6-7170, Part 6, Subject 51-00-00, Procedure 4 or 23Surface High Frequency Eddy Current (HFEC) Inspection Station 2231 Frame Inner Chords (surfaces) Inspect 1

(a) Do a surface HFEC inspection on the Station 2231 Frame Inner Chords (forward and aft surfaces) for cracks.

**FIGURE 5: HFEC INSPECTION (SHEET 3 OF 3)**  Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: September 18, 2003 747-53A2494 Revision 1 January 09, 2015 45 of 48 **BOEING SERVICE BULLETIN 747-53A2494 ALERT**  **ALERT This Appendix applies only to: Group 1-4, Configuration 1.** 

**APPENDIX A: LOGIC DIAGRAM (SHEET 1 OF 2)**  Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: September 18, 2003 747-53A2494 Revision 1 January 09, 2015 46 of 48 **BOEING SERVICE BULLETIN 747-53A2494 ALERT**  **ALERT APPENDIX A: LOGIC DIAGRAM**  **(SHEET 2 OF 2)** Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: September 18, 2003 747-53A2494 Revision 1 January 09, 2015 47 of 48 **BOEING SERVICE BULLETIN 747-53A2494 ALERT**  **ALERT This Appendix applies only to: Group 1-4, Configuration 2.** 

**APPENDIX B: LOGIC DIAGRAM (SHEET 1 OF 1)**  Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: September 18, 2003 747-53A2494 Revision 1 January 09, 2015 48 of 48 **BOEING SERVICE BULLETIN 747-53A2494 ALERT**  **ALERT**