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Original Issue: April 21, 2005 Revision 1: June 17, 2010 747-53A2502 BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. 1 of 230
ALERT ALERT Commercial Airplanes 747
ALERTALERT Service Bulletin Number: 747-53A2502 Original Issue: April 21, 2005 Revision 1: June 17, 2010 ATA System: 5300 SUBJECT: FUSELAGE - Non Stretched Upper Deck Tension Ties and Frames - Inspection and Repair.
BOEING PROPRIETARY, CONFIDENTIAL, AND/OR TRADE SECRET Copyright © 2005 The Boeing Company Unpublished Work - All Rights Reserved Boeing claims copyright in each page of this document only to the extent that the page contains copyrightable subject matter. Boeing also claims copyright in this document as a compilation and/or collective work.
This document includes proprietary information owned by The Boeing Company and/or one or more third parties. Treatment of the document and the information it contains is governed by contract with Boeing. For more information, contact The Boeing Company, P.O. Box 3707, Seattle, Washington 98124.
Boeing, the Boeing signature, the Boeing symbol, 707, 717, 727, 737, 747, 757, 767, 777, 787, Dreamliner, BBJ, DC-8, DC-9, DC-10, KC-10, KDC-10, MD-10, MD-11, MD-80, MD-88, MD-90, P-8A, Poseidon and the Boeing livery are all trademarks owned by The Boeing Company; and no trademark license is granted in connection with this document unless provided in writing by Boeing.
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Table of Contents Original Issue: April 21, 2005 Revision 1: June 17, 2010 747-53A2502 BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. 3 of 230 BOEING SERVICE BULLETIN 747-53A2502
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Table of Contents Revision Transmittal Sheet . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
1. PLANNING INFORMATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13 A. Effectivity . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
1. Airplanes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
2. Spares Affected . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27 B. Concurrent Requirements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27 C. Reason . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27 D. Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29 E. Compliance. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30 F. Approval . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33 G. Manpower . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33 H. Weight and Balance Changes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37 I. Electrical Load Data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37 J. References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37
1. Existing Data: . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37
2. Data supplied with this Service Bulletin: . . . . . . . . . . . . . . . . . . . . . . . . . 38
3. Installation Drawings Used in the Preparation of this Service Bulletin: . . . . . . . . . . 39 K. Publications Affected . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39 L. Interchangeability and Intermixability of Parts . . . . . . . . . . . . . . . . . . . . . . . . . 40
2. MATERIAL INFORMATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41 A. Material - Price and Availability. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41 B. Industry Support Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41 C. Parts Necessary For Each Airplane . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41
1. Kits/Parts: . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41
2. Parts and Materials Supplied by the Operator: . . . . . . . . . . . . . . . . . . . . . . 42
3. Parts Modified and Reidentified: . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 42
4. Parts Removed and Not Replaced: . . . . . . . . . . . . . . . . . . . . . . . . . . . . 42 D. Parts Necessary to Change Spares . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 42 E. Special Tooling - Price and Availability. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 42 F. Special Tooling Necessary to do this Service Bulletin . . . . . . . . . . . . . . . . . . . . . 42
3. ACCOMPLISHMENT INSTRUCTIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 43 A. GENERAL INFORMATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 43 B. WORK INSTRUCTIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45 FIGURE 1: INSPECTION - Group 1, Configuration 1 . . . . . . . . . . . . . . . . . . . . . . . . . . 64 FIGURE 2: OVERSIZED HOLE REPAIR - Group 1, Configuration 1 . . . . . . . . . . . . . . . . . . 73 FIGURE 3: INSPECTION - Group 1, Configuration 2 . . . . . . . . . . . . . . . . . . . . . . . . . . 80 FIGURE 4: OVERSIZED HOLE REPAIR - Group 1, Configuration 2 . . . . . . . . . . . . . . . . . . 90 FIGURE 5: INSPECTION - Group 1, Configuration 3 . . . . . . . . . . . . . . . . . . . . . . . . . . 99 FIGURE 6: OVERSIZED HOLE REPAIR - Group 1, Configuration 3 . . . . . . . . . . . . . . . . . . 107 FIGURE 7: INSPECTION - Group 1, Configuration 4 . . . . . . . . . . . . . . . . . . . . . . . . . . 114 FIGURE 8: OVERSIZE HOLE REPAIR - Group 1, Configuration 4 . . . . . . . . . . . . . . . . . . . 122 FIGURE 9: ACCESS - Group 2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 128 FIGURE 10: INSPECTION - Group 2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 130 FIGURE 11: OVERSIZED HOLE REPAIR - Group 2 . . . . . . . . . . . . . . . . . . . . . . . . . . 136
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FIGURE 12: CLOSE ACCESS - Group 2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 141 FIGURE 13: INSPECTION - Group 3. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 143 FIGURE 14: OVERSIZED HOLE REPAIR - Group 3. . . . . . . . . . . . . . . . . . . . . . . . . . 149 FIGURE 15: INSPECTION - Group 4. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 154 FIGURE 16: OVERSIZED HOLE REPAIR - Group 4. . . . . . . . . . . . . . . . . . . . . . . . . . 163 FIGURE 17: INSPECTION - Group 5. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 170 FIGURE 18: OVERSIZE HOLE REPAIR - Group 5 . . . . . . . . . . . . . . . . . . . . . . . . . . 179 FIGURE 19: INSPECTION - Group 6 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 186 FIGURE 20: OVERSIZE HOLE REPAIR - Group 6 . . . . . . . . . . . . . . . . . . . . . . . . . . 194 FIGURE 21: HFEC INSPECTION OF HOLES FOR INSULATION BLANKET STUDS . . . . . . . . 201 FIGURE 22: ONE-TIME INSPECTION FOR CORRECT CONFIGURATION - Group 2 . . . . . . . . 204 FIGURE 23: ADDITIONAL INSPECTION OF INCORRECT CONFIGURATION - Group 2 . . . . . . 218 APPENDIX A: DELETED . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 223 APPENDIX B: TENSION TIE DISCONNECTION METHODS . . . . . . . . . . . . . . . . . . . . . 224 APPENDIX C: GENERAL ILLUSTRATIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 226
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ALERT ALERT Commercial Airplanes 747
ALERTALERT Service Bulletin Number: 747-53A2502 Revision Transmittal Sheet Original Issue: April 21, 2005 Revision 1: June 17, 2010 ATA System: 5300 SUBJECT: FUSELAGE - Non Stretched Upper Deck Tension Ties and Frames - Inspection and Repair.
This Revision includes all pages of the service bulletin.
COMPLIANCE INFORMATION RELATED TO THIS REVISION Group 2: More work is necessary on airplanes changed as shown in the original issue of this service bulletin.
After additional analysis of the tension tie structure, Boeing has determined that the initial inspection of tension ties at STA 720, STA 740, and STA 760 should be done at an earlier time. The new compliance time for the initial inspection is given in paragraph 1.E., Compliance. In addition, a new one-time inspection (and corrective action, as necessary) has been added to ensure the configuration of all tension ties on Group 2 airplanes is in accordance with production engineering configuration.
Group 1, 3-6: No more work is necessary on airplanes changed as shown in the original issue of this service bulletin. However, all previously released actions given in this service bulletin have been upgraded from "Special Attention" status to "Alert" status based on the current criteria for determination of airplane safety related issues.
Federal Aviation Administration (FAA) Airworthiness Directive 84-19-01, is related to this service bulletin.
Federal Aviation Administration (FAA) Airworthiness Directive 94-13-06, is related to this service bulletin.
Federal Aviation Administration (FAA) Airworthiness Directive 2004-07-22 R1, is related to this service bulletin.
Federal Aviation Administration (FAA) Airworthiness Directive 2006-01-07, is related to this service bulletin.
REASON FOR REVISION This revision is sent to reduce the initial inspection compliance time for Group 2 airplanes at STA 720, STA 740, and STA 760 and to add an inspection to ensure the correct tension tie configurations on Group 2 airplanes.
Other changes have also been made in Revision 1.
Terminology has been changed in the Work Instruction to agree with the terminology defined in Paragraph 3.A., General Information - Notes.
These sections were changed:
— In Summary: Updated to reflect current information and requirements.
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— In paragraph 1.C., Reason: Updated to reflect current information and requirements.
— In paragraph 1.D., Description: Clarified description of existing work, and added description of new requirements for Group 2 airplanes.
— In paragraph 1.E., Compliance: Revised compliance information for existing inspection requirements for Group 2 airplanes. Added Table 4 for compliance information related to new inspections. Updated Airworthiness Directive references.
— In paragraph 1.F., Approval: Updated approval paragraph and existing AMOC statements. Added AMOC statement for AD 2006-01-07.
— In paragraph 1.G., Manpower: Revised notes in some tables. Added table for new inspection requirements.
— In paragraph 1.J., References: Has been updated.
— In paragraph 1.K., Publications Affected: Added Damage Tolerance Inspection statement.
— In paragraph 2.A., Material - Price and Availability: Added tension tie segment and tension tie splice channel.
— In paragraph 2.B., Industry Support Information: Added warranty statement for the new one-time inspection and corrective actions for 747-400F airplanes.
— In paragraph 2.C., Parts Necessary For Each Airplane: Added tension tie segment and tension tie splice channel.
— In paragraph 3.A., General Information: Updated, clarified, and corrected existing notes. Added notes 22, 23, and 24.
— In paragraph 3.B., Work Instructions: Added one-time inspection for correct configuration (Revision 1 - more work). Updated AMM references in ACCESS and RESTORATION section. Added SRM references for tension tie repairs and frame repairs. Also, clarified and/or removed redundant steps throughout this section. Changes to this section have resulted in re-sequencing and/or re-numbering of some steps.
— In Figures 1, 3, 5, 7, 10, 13, 15, 17, and 19: Clarified notes (e) and (g), corrected note (d) step number reference in some inspection figures, and corrected and/or revised some view section arrows and view callouts. Also, added inspection requirement for aluminum channel at STA 940, which was previously in the Work Instructions.
— In Figures 10, 11, 13, and 14: Corrected SRM references.
— Figure 22: This new figure has been added for one-time inspection for correct tension tie configuration on 747-400F airplanes (Group 2 only).
— Figure 23: This new figure has been added to give additional inspection requirements if an incorrect tension tie configuration is found (Group 2 only).
— Appendix A: The Appendix has been deleted. In the original issue of this service bulletin, Appendix A was a logic diagram of inspection requirements. Logic diagrams are no longer maintained to match current compliance information.
— Appendix B: Deleted Method 2 and 4 for disconnecting tension ties. Method 2 and 4, that were specified in the original issue, are no longer recommended.
The data given in Information Notice 747-53-2502 IN 01 is included in this revision Paragraph 1.A., Effectivity, shows changes of airplane operators. Each operator should examine the Effectivity paragraph for changes.
Vertical lines are put on the left edge of each page, except in Paragraph 1.A., Effectivity, to show the location of important changes.
Pages with no vertical lines have no important changes.
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REVISION HISTORY Original Issue: April 21, 2005 Revision 1:
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ALERT ALERT Commercial Airplanes 747
ALERTALERT Service Bulletin Number: 747-53A2502 Summary Original Issue: April 21, 2005 Revision 1: June 17, 2010 ATA System: 5300 SUBJECT: FUSELAGE - Non Stretched Upper Deck Tension Ties and Frames - 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 the work given in this service bulletin will make sure the tension ties and frames aft of the upper deck floor are not cracked. Cracks in tension ties and/or frames could cause the tension ties to become severed or disconnected from the frames. Severed or disconnected tension ties and/or frames at multiple locations could result in rapid in-flight decompression.
Tension ties are installed to connect the left and right hand sides of the body structure aft of the upper deck floor.
During routine maintenance of a 747-200F airplane one operator reported a crack in the tension tie, at the body station (STA) 820 frame connection. The crack was found to be 1/8 inch at a fastener hole. Inspection of the 747SR fatigue test airplane showed similar cracks in both the tension ties and frames at the tension tie to frame connections. The cracks were found at STA 800, 820, and 840 at 40,000 flight cycles (20,000 operating cycles, 20,000 test cycles). Cracks in the frames were up to 1.25 inches long, and cracks in the tension ties were up to
0.20 inches long.
Revision 1: Subsequent to the release of the original issue of this service bulletin, an operator reported finding a total of twelve cracks on forward and aft tension tie channels at STA 740 and STA 760 on a 747-400F airplane.
After comparing the structure to the Boeing design configuration, it was determined that only seven fasteners were installed common to the frame at each end of the STA 760 tension tie. A quantity of nine fasteners should have been installed common to the frame at each end of the tension tie.
Revision 1: After investigation, it has been determined that the airplane on which the discrepancy was found was manufactured and delivered by Boeing with the incorrect tension tie configuration at STA 760. Reduced load carrying capability of the STA 760 tension tie, due to cracks, subsequently lead to increased loads and premature fatigue cracks in the adjacent tension tie at STA 740.
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Revision 1: 747-200F airplanes and Boeing modified 747 Special Freighter airplanes have a unique tension tie configuration at STA 760, and only 747-400F airplanes have tension ties at STA 720 and STA 740. Therefore, only 747-400F airplanes are affected by the new inspection for correct configuration which was added in Revision 1.
Revision 1: In addition, due to new analysis of the tension tie structure, Boeing has determined that stresses are higher in the STA 720, STA 740, and STA 760 tension ties on 747-400F airplanes. Therefore, even if the tension tie configurations are correct, the detailed and high frequency eddy current (HFEC) inspections given in this service bulletin should begin at an earlier time. This has resulted in a reduced flight cycle compliance time for the initial inspection threshold at STA 720, STA 740, and STA 760 tension ties on 747-400F airplanes.
This service bulletin provides instructions for inspections and repair of the tension ties and frames aft of the upper deck floor.
The tension ties and frames have been found to be structually significant in that it is critical to the structual integrity of the airplane. tension tie and frame cracks not found before they reach critical crack lengths can cause in-flight depressurization. If the work given in this service bulletin is not done the airplane structure may not be able to withstand current regulatory fail-safe loads.
Boeing Service Related Problem (SRP) 747OP-SRP-53-0200 is related to this service bulletin.
Boeing Service Related Problem (SRP) 747-SRP-53-0349 is related to this service bulletin.
Boeing Fleet Team Digest (FTD) article 747-FTD-53-09008 is related to this service bulletin.
Modification Service Bulletin 747-53A2605 has been released to address Widespread Fatigue Damage (WFD) in the tension ties and adjacent frame structure. Accomplishment of the modification in accordance with Service Bulletin 747-53A2605 will terminate the repeat inspection requirements of this service bulletin.
ACTION (PRR 85901-46RS) Group 1, 3-6: Get access to all tension ties. Do detailed and HFEC inspections for cracks in all tension ties, adjacent frame structure, and adjacent structure that attaches to the tension ties. If any crack is found, repair as specified in this service bulletin, before further flight. Repeat inspections at the specified intervals.
Group 2: Do detailed and HFEC inspections for cracks in the tension ties and adjacent structure. If cracks are found, do the repair given in this service bulletin before further flight. Repeat inspections at the specified intervals. In addition, do a one-time general visual inspection at each tension tie location to determine if the correct design configuration is installed. At any tension tie where the correct configuration is not installed, do detailed and open hole HFEC inspections for cracks in the tension tie channels where they attach to the side of body frames. If no crack is found, install the correct tension tie configuration. If any crack is found, repair the tension tie in accordance with this service bulletin, or contact Boeing for repair instructions.
All actions specified in this section should be done at the times given in paragraph 1.E., Compliance.
This service bulletin contains only a flight safety inspection program. The flight safety inspection program is the minimum inspection program to maintain the structural integrity of the affected area of the airplane. An optional economics based inspection, to be done earlier than the flight safety inspection, would usually be included in this type of bulletin. However, for this area there is no economics based inspection program. The repair necessary when a crack is found in the flight safety inspection is the same as the repair necessary if a crack is found earlier.
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EFFECTIVITY 747-100, 747-100B, 747-200B, 747-200C, 747-200F, 747-400F, 747SP, and 747SR airplanes. Refer to paragraph 1.A.1., Airplanes, for the list of affected airplanes.
COMPLIANCE Refer to paragraph 1.E., Compliance.
Federal Aviation Administration (FAA) Airworthiness Directive AD 84-19-01 is related to this service bulletin.
Federal Aviation Administration (FAA) Airworthiness Directive AD 94-13-06 is related to this service bulletin.
Federal Aviation Administration (FAA) Airworthiness Directive AD 2004-07-22 R1 is related to this service bulletin.
Federal Aviation Administration (FAA) Airworthiness Directive AD 2006-01-07 is related to this service bulletin.
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.
INDUSTRY SUPPORT INFORMATION Boeing warranty remedies are not available for the inspection or repair procedures given in this service bulletin, except for the one-time inspection and corrective actions related to inspection for incorrect configurations on 747-400F airplanes. Please refer to Paragraph 2.B., Industry Support Information section of this service bulletin for more information.
MANPOWER Refer to Paragraph 1.G., Manpower.
MATERIAL INFORMATION Operator Supplied Parts/Materials.
Refer to Paragraph 2.A., Material - Price and Availability.
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FRAME (TYPICAL)
TENSION TIE (TYPICAL)
HORIZONTAL SHEAR WEB (TYPICAL BOTH SIDES)
SLOPING SHEAR WEB (TYPICAL BOTH SIDES)
INSPECT TENSION
TIES, FRAMES, AND
ADJACENT STRUCTURE FOR FATIGUE CRACKS.
ON 747-400F