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Commercial Airplanes 747 Service Bulletin Number: 747-55A2050 Original Issue: February 28, 2002 Revision 2: January 23, 2015 ATA System: 5510 SUBJECT: STABILIZERS - Horizontal Stabilizer - Upper Skin and Upper Rear Spar Chord 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 © 2002 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Unpublished Work.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: February 28, 2002 747-55A2050Revision 2: January 23, 2015 1 of 249
4.0
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Original Issue: February 28, 2002 747-55A2050Revision 2: January 23, 2015 2 of 249 BOEING SERVICE BULLETIN 747-55A2050
BLANK PAGE
Table of Contents
Revision Transmittal Sheet5
Summary ..................................................... 1 1
1. PLANNING INFORMATION ........................................ 1 5 A. Effectivity ............................................... 1 5
1. Airplanes ............................................ 1 5
2. Spares Affected ........................................ 2 5 B. Concurrent Requirements ...................................... 2 5 C. Reason ................................................ 2 6 D. Description .............................................. 2 7 E. Compliance .............................................. 3 2 F. Approval ............................................... 6 1 G. Manpower .............................................. 6 2 H. Weight and Balance Changes .................................... 6 6 I. Electrical Load Data ......................................... 6 6 J. References .............................................. 6 6
1. Existing Data: ......................................... 6 6
2. Data Supplied with this Service Bulletin: ........................... 6 7
3. Installation Drawings Used in the Preparation of this Service Bulletin: ........... 6 7 K. Publications Affected ........................................ 6 7 L. Interchangeability and Intermixability of Parts ........................... 6 8 M. Software Accomplishment Summary ................................ 6 8
2. MATERIAL INFORMATION ........................................ 6 9 A. Material - Price and Availability ................................... 6 9 B. Industry Support Information .................................... 7 0 C. Parts Necessary for Each Airplane ................................. 7 0
1. Kits/Parts: ........................................... 7 0
2. Parts and Materials Supplied by the Operator: ........................ 7 6
3. Parts Modified and Reidentified: ............................... 7 8
4. Parts Removed and Not Replaced: .............................. 7 8 D. Parts Necessary to Change Spares ................................. 7 8 E. Special Tooling - Price and Availability ............................... 7 8 F. Special Tooling Necessary to do this Service Bulletin ....................... 7 8
3. ACCOMPLISHMENT INSTRUCTIONS .................................. 7 9 A. GENERAL INFORMATION ..................................... 7 9 B. WORK INSTRUCTIONS ....................................... 8 0 FIGURE 1: LOGIC DIAGRAM OF INSPECTION AND MAINTENANCE ALTERNATIVES ....... 9 1 FIGURE 2: ZONE A - DETAILED AND NDT INSPECTION ........................ 9 3 FIGURE 3: ZONE B - NDT INSPECTION (GROUP 1, 2, AND 3 AIRPLANES) [Group 1-3] ...... 9 9 FIGURE 4: ZONE B - OPEN HOLE NDT INSPECTION (GROUP 1 AND 2 AIRPLANES) [Group 1-2] . 109 FIGURE 5: ZONE B - OPEN HOLE NDT INSPECTION (GROUP 3 AIRPLANES) [Group 3] ..... 1 2 1 FIGURE 6: ZONE B - OPEN HOLE NDT INSPECTION (GROUP 4, 5, 7, 8, AND 9 AIRPLANES) [Group 4-5, 7-9] ............................................ 1 3 3 FIGURE 7: ZONE B - OPEN HOLE NDT INSPECTION (GROUP 6 AIRPLANES) [Group 6] ..... 1 4 5 FIGURE 8: ZONE C MARAGING OR H-11 STEEL FASTENER INSPECTION (GROUP 1, 2, AND 3 AIRPLANES) [Group 1-3] ................................... 1 5 8 Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details.
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FIGURE 9: ZONE C ADDITIONAL MARAGING OR H-11 STEEL FASTENER INSPECTION (GROUP 1, 2, AND 3 AIRPLANES) [Group 1-3] ............................... 1 6 3 FIGURE 10: ZONE B MODIFICATION [Group 1-2] ............................ 1 6 6 FIGURE 11: ZONE B MODIFICATION [Group 3] ............................. 1 7 9 FIGURE 12: ZONE B MODIFICATION [Group 4-9] ............................ 1 9 5 FIGURE 13: ZONE B POST-MODIFICATION INSPECTION [Group 1-2] ................ 2 1 0 FIGURE 14: ZONE B POST-MODIFICATION INSPECTIONS [Group 3] ................ 2 1 7 FIGURE 15: ZONE B POST-MODIFICATION INSPECTIONS [Group 4-5, 7-9] ............. 2 2 4 FIGURE 16: ZONE B POST-MODIFICATION INSPECTIONS [Group 6] ................ 2 3 1 APPENDIX A: FLIGHT SAFETY SECTION ................................. 2 3 9 APPENDIX B: FEEDBACK FORM - EDGE MARGINS AND END MARGINS ............... 2 4 0 APPENDIX C: LOGIC DIAGRAM OF ZONE B INSPECTION [Group 1-6] ................. 2 4 8 Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details.
Original Issue: February 28, 2002 747-55A2050Revision 2: January 23, 2015 4 of 249 BOEING SERVICE BULLETIN 747-55A2050
Commercial Airplanes 747 Service Bulletin Revision Transmittal SheetNumber: 747-55A2050Original Issue: February 28, 2002 Revision 2: January 23, 2015 ATA System: 5510 SUBJECT: STABILIZERS - Horizontal Stabilizer - Upper Skin and Upper Rear Spar Chord Inspection This revision includes all pages of the service bulletin.
COMPLIANCE INFORMATION RELATED TO THIS REVISION Federal Aviation Administration (FAA) Airworthiness Directive AD 2006-10-16 and AD 2004-07-22 R1 are related to this service bulletin.
More work is necessary on airplanes inspected in accordance with the original issue and Revision 1 of this service bulletin. Do the inspections at the new compliance times given in Paragraph 1.E., Compliance. For Zone B inspection, continue to do the inspections at the new compliance times given in Paragraph 1.E., Compliance, until the optional Zone B modification is accomplished. For Zone C inspection, do additional Maraging or H-11 steel fastener inspection at the time given in Paragraph 1.E., Compliance.
No airplanes were added to this service bulletin effectivity; however, new airplane groups (7, 8, and 9) were added. Airplane line number 904 (RT876) was moved from Group 5 to Group 7. Airplanes line numbers 766 (RT631) and 778 (RT632) were moved from Group 5 to Group 8. Airplane line number 932 (RT743) was moved from Group 5 to Group 9.
REASON FOR REVISION This revision is sent to give reduced compliance times for Zone B inspection requirements, Zone B modification instructions, Zone B post-modification inspection instructions, additional Zone C Maraging or H-11 steel fastener inspection, and instructions to install Inconel or titanium fasteners at locations where Maraging or H-11 steel fasteners are removed. After the original issue of this service bulletin, multiple operators have reported crack findings before reaching the compliance times given in this service bulletin. Based on the additional fleet information, reduced compliance times are necessary in Zone B to detect early cracking. Due to the changes in compliance times for Zone B inspection requirements, Zone B compliance information in FIGURE 1 logic diagram was converted to a table format and moved to Paragraph 1.E., Compliance. New airplane groups were added to the effectivity to give separate compliance times for 747-400 Large Cargo Freighter (LCF) airplanes in Paragraph 1.E., Compliance. Optional Zone B modification and its post-modification inspections are given to terminate the Zone B repeat inspection requirements. Fastener hole sizes and torque values were updated in the Fastener Tables. In Zone C, additional Maraging and H-11 steel fastener inspection is necessary to make sure there are no cracked or fractured fasteners. For the additional Zone C inspection, separate compliance information and inspection instructions are added. Instructions are changed to install Inconel or titanium fasteners at locations where Maraging or H-11 steel fasteners are removed. Re-installation of Maraging or H-11 steel fastener is not acceptable in accordance with paragraph (n) of AD 2006-10-16.
The data given in Information Notice 747-55A2050 IN 01 is included in this revision; however, the information was changed due to the changes given in this revision.
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Original Issue: February 28, 2002 747-55A2050Revision 2: January 23, 2015 5 of 249
The data given in Information Notice 747-55A2050 IN 02 is included in this revision.
The data given in Alternative Method of Compliance Notice 747-55A2050-AMOC-01 is included in this revision.
Terminology has been changed in the Work Instructions to agree with the terminology defined in Paragraph
3.A., General Information - Notes.
These sections were changed:
1. In Summary, Background, updated the service history and added a planning table.
2. In Summary, Action, added headings with applicable zones and clarified repair instructions. Updated Zone C information to match work instructions and added group applicability. Added information about the optional Zone B modification.
3. In Summary, Effectivity, clarified the summary of the service bulletin effectivity by listing the minor models.
4. In Summary, Compliance, updated the FAA AD reference with the effective date of the FAA AD. Added FAA AD 2006-10-16, which supersedes AD 2002-06-02. Clarified the affected zones for the compliance information related to FIGURE 1 and added group applicability. Added a reference to Paragraph 1.E., Compliance, for the new and changed compliance information.
5. In Summary, Manpower, updated the reference to Paragraph 1.G., Manpower.
6. In Summary, Material Information, added information regarding operator supplied parts.
7. In Summary Figure, updated existing inspection summary and added information about the optional Zone B modification.
8. In Paragraph 1.A.1., Airplanes, converted existing Group Configuration information into a table format.
Existing group descriptions were updated but no airplanes were added to the effectivity. 747-400 LCF airplanes in Group 5 were moved to new airplane Groups 7, 8, and 9. Also, updated the effectivity list in variable numbers.
9. In Paragraph 1.C., Reason, updated the service history and added a reason for this revision.
10. In Paragraph 1.D., Description, updated the "contact Boeing" phrase for repair instructions and group applicability. Changed Zone C inspection requirements to prevent re-installation of Maraging or H-11 steel fasteners by deleting optional Magnetic Particle Inspection (MPI) and Fluorescent Penetrant Inspection (FPI). Clarified the terminating action requirement for Zone C inspections. Added information about additional Zone C inspection requirement, optional Zone B modification, "more work" statement for this revision, and affected maintenance zones tables.
11. In Paragraph 1.E., Compliance:
– Updated the FAA AD reference with the effective date of the FAA AD. Added FAA AD 2006-10-16, which supersedes AD 2002-06-02.
– Clarified the description of FIGURE 1 logic diagram.
– Zone B compliance information in FIGURE 1 logic diagram was converted and added to Tables 1 through 5.
– Added Tables 6 through 8 to give compliance information for 747-400 LCF airplanes, which was previously given in Boeing Service Bulletin 747-53A2817.
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– Additional information was added to clarify the compliance information in Tables 6 through 8 and Boeing Service Bulletin 747-53A2817.
– Added Table 9 to give compliance information for additional Zone C inspection.
– Added Tables 10 through 14 to give compliance information for Zone B post-modification inspections.
12. In Paragraph 1.F., Approval, added an alternative method of compliance (AMOC) paragraph for AD 2006-10-16. Also, updated the AMOC paragraph for AD 2004-07-22 R1.
13. In Paragraph 1.G., Manpower, added table headers with corresponding "Part" of the work instructions.
Replaced the word "examine" with the corresponding figure number in each table. Updated manpower information for Zone B open hole NDT inspection to match the changes in the accomplishment instructions. Added manpower information for additional Zone C inspection, Zone B modification and Zone B post-modification inspections. Deleted optional MPI and FPI information from Part 5 (Table 8).
14. In Paragraph 1.J.1., Existing Data, updated the reference list.
15. In Paragraph 1.K., Publications Affected, added publications affected table and damage tolerance evaluation statement.
16. Added Paragraph 1.M., Software Accomplishment Summary.
17. In Paragraph 2.A., Material - Price and Availability, updated pricing information on the inspection top kits. Added top kit information for Zone B modification.
18. In Paragraph 2.C.1., Kits/Parts, updated the existing note to clarify the top kit information. Added parts list for the modification top kits.
19. In Paragraph 2.C.2., Parts and Materials Supplied by the Operator, added optional oversize fasteners for Zone B modification and necessary material information.
20. In Paragraph 3.A., General Information, updated existing notes and added new notes.
21. In Paragraph 3.B., Work Instructions:
– Access and Restoration instructions for Zones A, B, and C were moved to separate part of the work instructions to prevent repeated instructions.
– Access panel callouts have been updated in Access and Restoration instructions.
– Updated visual inspection terminology to match the general note.
– Updated SRM repair references and "contact Boeing" phrase for repair instructions.
– Added group applicability.
– Changed Zone C inspection requirements to prevent installation of Maraging or H-11 steel fasteners.
Deleted optional MPI and FPI in this section.
– Added additional Zone C inspection requirements.
– Clarified the terminating action requirement for Zone C Inspections.
– Added optional Zone B modification instructions.
– Added Zone B post-modification instructions.
22. In FIGURE 1, updated compliance information to be effective from the date of the AD and group applicability. Added optional Zone B modification. Deleted compliance information for Zone B inspections, which was moved to Paragraph 1.E., Compliance. Change Zone C Inspection requirements to prevent installation of Maraging or H-11 steel fasteners by deleting optional MPI and FPI.
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23. In FIGURE 2, change the task "Examine" to "Inspect." Clarified the type of inspection in the notes section and updated non-destructive test (NDT) references.
24. In FIGURE 3, change the task "Examine" to "Inspect." Added group applicability. Clarified the type of inspection in the notes section and updated NDT references. Also added a footnote to give instructions for areas with bushings or freeze plugs.
25. In FIGURE 4 and FIGURE 5:
– Added group applicability.
– Change the buttock line (BL) 40 to 43.5 in the graphic.
– Updated the fastener head orientation in fastener symbols.
– Change the task "Examine" to "Inspect."
– Updated NDT references.
– Clarified hole reaming and fastener removal/installation instructions.
– Changed the MPI and FPI inspections to the magnetic inspection of the bolts to find and discard any Maraging or H-11 steel fasteners and replace them with Inconel or titanium fasteners.
– Added a footnote to give instructions for areas with bushings or freeze plugs.
– Updated Table 1 to give torque values for fasteners installed in accordance with service bulletin 747-55-2045.
– Changed Flag Note 1 to refer to the magnetic inspection.
– Clarified Flag Notes 2 and 3.
– Deleted information regarding fastener substitution using Boeing Document D-590 and Boeing drawing 012W6100.
– Updated the fastener torque values.
– Updated fastener holes sizes to give close ream hole diameters.
– Added a footnote about the close ream holes.
26. In FIGURE 6:
– Added group applicability.
– Change the buttock line (BL) 40 to 43.5 in the graphic.
– Updated the fastener head orientation in fastener symbols.
– Change the task "Examine" to "Inspect."
– Updated NDT references.
– Clarified hole reaming and fastener removal/installation instructions.
– Added a footnote to give instructions for areas with bushings or freeze plugs.
– Changed Table 1 title.
– Clarified Flag Notes 3 and 4.
– Deleted information regarding fastener substitution using Boeing Document D-590 and Boeing drawing 012W6100.
– Updated the fastener torque values.
– Updated fastener holes sizes to give close ream hole diameters.
– Added a footnote about the close ream holes.
27. In FIGURE 7:
– Added group applicability.
– Change the buttock line (BL) 40 to 43.5 in the graphic.
– Updated the fastener head orientation in fastener symbols.
– Change the task "Examine" to "Inspect."
– Updated NDT references.
– Clarified hole reaming and fastener removal/installation instructions.
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– Added a manual reference for installing bonding jumper if removed.
– Added a footnote to give instructions for areas with bushings or freeze plugs.
– Deleted Table 1, which gave torque values for original production fasteners.
– Updated the fastener torque values.
– Updated fastener holes sizes to give close ream hole diameters.
– Added a footnote about the close ream holes.
– Deleted information regarding fastener substitution using Boeing Document D-590 and Boeing drawing 012W6100.
28. In FIGURE 8:
– Added group applicability.
– Change BL 40 to 43.5 in the graphic.
– Changed the task "Examine" to "Inspect."
– Deleted optional MPI and FPI, flag note table, and fastener torque value table to prevent installation of Maraging or H-11 steel fasteners.
– Deleted Flag Note 1 and MPI/FPI related steps in illustrations.
29. Added FIGURE 9 to give additional Zone C inspection.
30. Added FIGURE 10, FIGURE 11, and FIGURE 12 to give optional Zone B modification instructions.
31. Added FIGURE 13, FIGURE 14, FIGURE 15, and FIGURE 16 to give Zone B post-modification inspection instructions.
32. In APPENDIX A, updated Flight Safety Inspection Program information.
33. Added APPENDIX B to give feedback form for edge margins and end margins when contacting Boeing.
34. Added APPENDIX C to give logic diagram for Zone B inspection.
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 important changes.
REVISION HISTORY February 28, 2002Original Issue:
May 01, 2003Revision 1:
January 23, 2015Revision 2:
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Commercial Airplanes 747 Service Bulletin SummaryNumber: 747-55A2050Original Issue: February 28, 2002 Revision 2: January 23, 2015 ATA System: 5510 SUBJECT: STABILIZERS - Horizontal Stabilizer - Upper Skin and Upper Rear Spar Chord Inspection
CONCURRENT REQUIREMENTS None.
BACKGROUND This inspection when completed, will help to detect cracks in the horizontal stabilizer outboard and center section rear spar structure, hinge fittings, terminal fittings and splice plates. Cracks in this structure could cause significant degradation of the structural integrity of the horizontal stabilizer outboard and center sections and subsequent adverse effects on airplane controllability and possible loss of control of the airplane.
One operator has reported finding a 3.5 inch crack in the horizontal stabilizer center section aft upper skin. The crack was located at LBL 37.8 and ran 3.5 inches forward of the aft edge of the skin. The skin and rear spar upper chord are subject of Supplemental Structural Inspection Document (SSID) E-3C. However, the airplane that the crack was found on was not a SSID candidate airplane.
Subsequent to the original issue of this service bulletin multiple operators have reported cracks in the splice plates, hinge fittings, terminal fittings, and outboard and center section upper skin, upper chord, and rear spar web. Operators have also reported cracked and fractured Maraging steel fasteners. The cracks have been reported on airplanes as early as 19,200 flight-cycles/24,300 flight-hours and 8,000 flight-cycles/54,800 flight-hours.
Inspection of the horizontal stabilizer hinge fitting halves, terminal fittings, splice plates, and the outboard and center section upper skins, rear spar upper chords, and rear spar webs for cracks and for cracked or fractured Maraging or H-11 steel fasteners will maintain the structural integrity of the horizontal stabilizer outboard and center sections.
Boeing Service Related Problem (SRP) 747OP-SRP-55-0023 and 747OP-SRP-55-0027 are related to this service bulletin.
The Federal Aviation Administration (FAA) has issued an Airworthiness Directive (AD) which requires incorporation of 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 Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details.
Original Issue: February 28, 2002 747-55A2050Revision 2: January 23, 2015 11 of 249
ReferenceAffectedPlanning Data 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 AffectedYesPublications Affected Paragraph 1.K., Publications AffectedNoAirplane Flight Operations Affected (Flight Crew Operations Manual and/or FAA Approved Airplane Flight Manual) Paragraph 2.C.1., Kits/PartsYesKits/Parts Required Paragraph 2.C.2., Parts and Materials Supplied by the Operator YesOperator Supplied Parts/Material Paragraph 2.F., Special Tooling Necessary to do this Service Bulletin NoSpecial Tooling Required ACTION Zone A and Zone B Inspections: Gain access to the aft upper end of the horizontal stabilizer outboard and center sections, internal and external. Perform detailed and/or NDT inspections of the splice fittings, terminal fittings, hinge fitting halves, and the outboard and center section upper skins, rear spar upper chords, and rear spar webs. If any crack is found, repair cracks in accordance with the SRM or contact Boeing for repair instructions and do the repair.
Group 1-3:
Zone C Inspection: Do a magnetic inspection of the fasteners common to the outboard and center section rear spar upper chords to determine if they are magnetic or non-magnetic. If a bolt is magnetic, it is made from Maraging or H-11 steel. If a bolt is not magnetic, it is not made from Maraging or H-11 steel and no further action is required at that fastener location. If a bolt is magnetic, do an ultrasonic inspection for cracking or fracture. If any cracked or fractured fastener is found, replace the fastener with Inconel or titanium fastener. No further action is required once all Maraging or H-11 steel fasteners are replaced with Inconel or titanium fasteners in this inspection zone.
Zone B Modification: Do optional Zone B modifications in accordance with this service bulletin, which is terminating action for the Zone B and Zone C repeat inspections. Make sure that the fastener holes that exist are free of cracks, then make the fastener holes 1/16 inch oversize in diameter and install new fasteners in accordance with this service bulletin. After the modification is accomplished, do post-modification inspections at the time given in Paragraph 1.E., Compliance.
EFFECTIVITY All 747-100, 747-100B, 747-100B SUD, 747-200B, 747-200C, 747-200F, 747-300, 747-400, 747-400D, 747-400F, 747SP, and 747SR airplanes. Refer to Paragraph 1.A.1., Airplanes for the list of affected airplanes.
COMPLIANCE Federal Aviation Administration (FAA) Airworthiness Directive AD 2006-10-16 and AD 2004-07-22 R1 are related to this service bulletin. The effective date of AD 2006-10-16 is June 21, 2006.
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