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October 30, 2008 747-54A2230 BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. 1 of 300
ALERT ALERT Commercial Airplane Group 747
ALERTALERT Service Bulletin Number: 747-54A2230 Date: October 30, 2008 ATA System: 5400 5430 SUBJECT: NACELLES / PYLONS - Front Spar Chord Inspection and Strut Cap Skin Installation
BOEING PROPRIETARY, CONFIDENTIAL, AND/OR TRADE SECRET Copyright © 2008 The Boeing Company Unpublished Work - All Rights Reserved Boeing claims copyright in each page of this document only to the extent that the page contains copyrightable subject matter.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, 707, 717, 727, 737, 747, 757, 767, 777, BBJ, BOEING BUSINESS JET, DC-8, DC-9, DC-10, MD-10, MD-11, MD-80, MD-90, the Boeing logo and the Boeing livery are among the trademarks owned by Boeing or its subsidiaries. No intellectual property license (express or implied) is granted in connection with this document or otherwise.
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Table of Contents Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
1. PLANNING INFORMATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11 A. Effectivity . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
1. Airplanes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
2. Spares Affected . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22 B. Concurrent Requirements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22 C. Reason . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22 D. Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22 E. Compliance. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24 F. Approval . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25 G. Manpower . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25 H. Weight and Balance Changes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35 I. Electrical Load Data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35 J. References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35
1. Existing Data: . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35
2. Data supplied with this Service Bulletin: . . . . . . . . . . . . . . . . . . . . . . . . . 35
3. Installation Drawings Used in the Preparation of this Service Bulletin: . . . . . . . . . . 36 K. Publications Affected . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36 L. Interchangeability and Intermixability of Parts . . . . . . . . . . . . . . . . . . . . . . . . . 36
2. MATERIAL INFORMATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37 A. Material - Price and Availability. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37 B. Industry Support Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40 C. Parts Necessary For Each Airplane . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40
1. Kits/Parts: . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40
2. Parts and Materials Supplied by the Operator: . . . . . . . . . . . . . . . . . . . . . . 63
3. Parts Modified and Reidentified: . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 63
4. Parts Removed and Not Replaced: . . . . . . . . . . . . . . . . . . . . . . . . . . . . 63 D. Parts Necessary to Change Spares . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 63 E. Special Tooling - Price and Availability. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 63 F. Special Tooling Necessary to do this Service Bulletin . . . . . . . . . . . . . . . . . . . . . 63
3. ACCOMPLISHMENT INSTRUCTIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 65 A. GENERAL INFORMATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 65 B. WORK INSTRUCTIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 66 FIGURE 1: STRUT NO. 1 - VARIABLE CAMBER FLAP SEAL FAIRING REMOVAL. . . . . . . . . . 80 FIGURE 2: STRUT NO. 1 - OPEN HOLE HIGH FREQUENCY EDDY CURRENT (HFEC) INSPECTION AND CAP SKIN DOUBLER INSTALLATION . . . . . . . . . . . . . . . . . . . . . . . 82 FIGURE 3: STRUT NO. 1 - OPEN HOLE HIGH FREQUENCY EDDY CURRENT (HFEC) INSPECTION .
89 FIGURE 4: STRUT NO. 1 - OPEN HOLE HIGH FREQUENCY EDDY CURRENT (HFEC) INSPECTION AND CAP SKIN DOUBLER INSTALLATION . . . . . . . . . . . . . . . . . . . . . . . 94 FIGURE 5: STRUT NO. 1 - OPEN HOLE HIGH FREQUENCY EDDY CURRENT (HFEC) INSPECTION .
100 FIGURE 6: STRUT NO. 1 - VARIABLE CAMBER FLAP SEAL FAIRING INSTALLATION . . . . . . . 104 FIGURE 7: STRUT NO. 2 - SKIRT SEAL REMOVAL . . . . . . . . . . . . . . . . . . . . . . . . . . 106 FIGURE 8: STRUT NO. 2 - SKIRT SEAL REMOVAL . . . . . . . . . . . . . . . . . . . . . . . . . . 109
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FIGURE 9: STRUT NO. 2 - SKIRT SEAL REMOVAL . . . . . . . . . . . . . . . . . . . . . . . . . 113 FIGURE 10: STRUT NO. 2 - SKIRT SEAL REMOVAL. . . . . . . . . . . . . . . . . . . . . . . . . 116 FIGURE 11: STRUT NO. 2 - SKIRT SEAL REMOVAL. . . . . . . . . . . . . . . . . . . . . . . . . 119 FIGURE 12: STRUT NO. 2 - SKIRT SEAL REMOVAL. . . . . . . . . . . . . . . . . . . . . . . . . 122 FIGURE 13: STRUT NO. 2 - OPEN HOLE HIGH FREQUENCY EDDY CURRENT (HFEC) INSPECTION AND CAP SKIN DOUBLER INSTALLATION . . . . . . . . . . . . . . . . . . . . . . 125 FIGURE 14: STRUT NO. 2 - OPEN HOLE HIGH FREQUENCY EDDY CURRENT (HFEC) INSPECTION 131 FIGURE 15: STRUT NO. 2 - OPEN HOLE HIGH FREQUENCY EDDY CURRENT (HFEC) INSPECTION AND CAP SKIN DOUBLER INSTALLATION . . . . . . . . . . . . . . . . . . . . . . 137 FIGURE 16: STRUT NO. 2 - OPEN HOLE HIGH FREQUENCY EDDY CURRENT (HFEC) INSPECTION 144 FIGURE 17: STRUT NO. 2 - OPEN HOLE HIGH FREQUENCY EDDY CURRENT (HFEC) INSPECTION 148 FIGURE 18: STRUT NO. 2 - SKIRT SEAL INSTALLATION . . . . . . . . . . . . . . . . . . . . . . 152 FIGURE 19: STRUT NO. 2 - SKIRT SEAL INSTALLATION . . . . . . . . . . . . . . . . . . . . . . 162 FIGURE 20: STRUT NO. 2 - SKIRT SEAL INSTALLATION . . . . . . . . . . . . . . . . . . . . . . 172 FIGURE 21: STRUT NO. 2 - SKIRT SEAL INSTALLATION . . . . . . . . . . . . . . . . . . . . . . 176 FIGURE 22: STRUT NO. 2 - SKIRT SEAL INSTALLATION . . . . . . . . . . . . . . . . . . . . . . 180 FIGURE 23: STRUT NO. 2 - SKIRT SEAL INSTALLATION . . . . . . . . . . . . . . . . . . . . . . 184 FIGURE 24: STRUT NO. 3 - SKIRT SEAL REMOVAL. . . . . . . . . . . . . . . . . . . . . . . . . 188 FIGURE 25: STRUT NO. 3 - SKIRT SEAL REMOVAL. . . . . . . . . . . . . . . . . . . . . . . . . 191 FIGURE 26: STRUT NO. 3 - SKIRT SEAL REMOVAL. . . . . . . . . . . . . . . . . . . . . . . . . 195 FIGURE 27: STRUT NO. 3 - SKIRT SEAL REMOVAL. . . . . . . . . . . . . . . . . . . . . . . . . 198 FIGURE 28: STRUT NO. 3 - SKIRT SEAL REMOVAL. . . . . . . . . . . . . . . . . . . . . . . . . 201 FIGURE 29: STRUT NO. 3 - SKIRT SEAL REMOVAL. . . . . . . . . . . . . . . . . . . . . . . . . 204 FIGURE 30: STRUT NO. 3 - OPEN HOLE HIGH FREQUENCY EDDY CURRENT (HFEC) INSPECTION AND CAP SKIN DOUBLER INSTALLATION . . . . . . . . . . . . . . . . . . . . . . 207 FIGURE 31: STRUT NO. 3 - OPEN HOLE HIGH FREQUENCY EDDY CURRENT (HFEC) INSPECTION 213 FIGURE 32: STRUT NO. 3 - OPEN HOLE HIGH FREQUENCY EDDY CURRENT (HFEC) INSPECTION AND CAP SKIN DOUBLER INSTALLATION . . . . . . . . . . . . . . . . . . . . . . 219 FIGURE 33: STRUT NO. 3 - OPEN HOLE HIGH FREQUENCY EDDY CURRENT (HFEC) INSPECTION 226 FIGURE 34: STRUT NO. 3 - OPEN HOLE HIGH FREQUENCY EDDY CURRENT (HFEC) INSPECTION 230 FIGURE 35: STRUT NO. 3 - SKIRT SEAL INSTALLATION . . . . . . . . . . . . . . . . . . . . . . 234 FIGURE 36: STRUT NO. 3 - SKIRT SEAL INSTALLATION . . . . . . . . . . . . . . . . . . . . . . 244 FIGURE 37: STRUT NO. 3 - SKIRT SEAL INSTALLATION . . . . . . . . . . . . . . . . . . . . . . 254 FIGURE 38: STRUT NO. 3 - SKIRT SEAL INSTALLATION . . . . . . . . . . . . . . . . . . . . . . 258 FIGURE 39: STRUT NO. 3 - SKIRT SEAL INSTALLATION . . . . . . . . . . . . . . . . . . . . . . 262 FIGURE 40: STRUT NO. 3 - SKIRT SEAL INSTALLATION . . . . . . . . . . . . . . . . . . . . . . 266 FIGURE 41: STRUT NO. 4 - VARIABLE CAMBER FLAP SEAL FAIRING REMOVAL . . . . . . . . 270 FIGURE 42: STRUT NO. 4 - OPEN HOLE HIGH FREQUENCY EDDY CURRENT (HFEC) INSPECTION AND CAP SKIN DOUBLER INSTALLATION . . . . . . . . . . . . . . . . . . . . . . 272 FIGURE 43: STRUT NO. 4 - OPEN HOLE HIGH FREQUENCY EDDY CURRENT (HFEC) INSPECTION 279
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FIGURE 44: STRUT NO. 4 - OPEN HOLE HIGH FREQUENCY EDDY CURRENT (HFEC) INSPECTION AND CAP SKIN DOUBLER INSTALLATION . . . . . . . . . . . . . . . . . . . . . . . 284 FIGURE 45: STRUT NO. 4 - OPEN HOLE HIGH FREQUENCY EDDY CURRENT (HFEC) INSPECTION 290 FIGURE 46: STRUT NO. 4 - VARIABLE CAMBER FLAP SEAL FAIRING INSTALLATION . . . . . . 294 APPENDIX A: MASTER FASTENER CODE LIST. . . . . . . . . . . . . . . . . . . . . . . . . . . . 296 APPENDIX B: SCOPE OF CHANGE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 299
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October 30, 2008 747-54A2230 BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. 7 of 300
ALERT ALERT Commercial Airplane Group 747
ALERTALERT Service Bulletin Number: 747-54A2230 Summary Date: October 30, 2008 ATA System: 5400 5430 SUBJECT: NACELLES / PYLONS - Front Spar Chord Inspection and Strut Cap Skin Installation
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 inspection and modification in this service bulletin will detect and help prevent cracking and fracture of the nacelle strut front spar chord assembly forward of the upper link attachment. Fracture of the front spar chord assembly will result in the loss of the strut upper link load path. Continued operation without the strut upper link load path could result in the fracture of the diagonal brace and result in an in-flight separation of the strut and engine.
The front spar chord assembly is used to connect the strut to the upper link. Subsequent to the original issue of Boeing Service Bulletin 747-54A2224 Original Issue, an operator reported finding a fractured chord on Strut no. 3 on an airplane with approximately 79,800 flight-hours and 15,100 flight-cycles. The fracture occurred forward of the rear engine mount bulkhead due to cracking that initiated and was propagated by fatigue from a fastener hole. Loss of the upper link load path would result in the transfer of additional loads to the diagonal brace load path. The additional loads could result in the fracture of the diagonal brace. The loss of the upper link load path combined with the loss of the diagonal brace load path could result in the in-flight separation of the strut and engine.
Inspection of the front spar chord assembly will detect cracks or fractures of the front spar chord assembly.
Installation of a cap skin doubler, if not previously accomplished, and oversizing of the holes will reduce the potential for cracks from developing in the front spar chord assembly fastener holes and help prevent cracks or fractures in the front spar chord assemblies.
Boeing Service Related Problem (SRP) 747OP-SRP-54-0117 is related to this service bulletin.
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ACTION Part 1 - Outboard Strut Inspection and Modification Remove the strut access panels as required. Remove the variable camber flap fairing (not required on JT9D-3 / -7 powered airplanes which have already installed the cap skin doubler in accordance with 747-54-2125).
Relieve the load from the front spar chord, as required. Remove the fasteners common to the front spar chord from the rear engine mount bulkhead forward to the next frame. Do an open hole High Frequency Eddy Current (HFEC) inspection for cracks. If any crack is found, contact The Boeing Company for additional instructions. If the cap skin doubler was not previously installed in accordance with 747-54-2125, install the cap skin doubler.
Install the variable camber flap fairing, if removed. Install the strut access panels.
Part 2 - Inboard Strut Inspection and Modification Remove the strut access panels. For airplanes that have not installed the cap skin doubler in accordance with 747-54-2125, remove the engine and strut. For airplanes that have not installed the cap skin doubler in accordance with 747-54-2125, remove and cut the skirt seal. For airplanes that have already installed the cap skin doubler in accordance with 747-54-2125, remove the skirt seal. Relieve the load from the front spar chord, as required. For JT9D-3/ -7 powered airplanes that have already installed the cap skin doubler in accordance with 747-54-2125, remove the cap skin doubler to gain access to fasteners that are covered by the doubler.
Remove the fasteners common to the front spar chord from the rear engine mount bulkhead forward to the next frame. Do an open hole High Frequency Eddy Current (HFEC) inspection for cracks. If any crack is found, contact The Boeing Company for additional instructions. Reinstall the cap skin doubler or If the cap skin doubler was not previously installed in accordance with 747-54-2125, install the cap skin doubler. Reinstall the skirt seal or for airplanes that have not installed the cap skin doubler, rework the skirt seal to accommodate the cap skin doubler and reinstall. Install the engine and strut, if removed. Install the strut access panels
EFFECTIVITY 747-100, -100B, -100B SUD, -200B, -200C, -200F, -300, -SP, and -SR airplanes with JT9D-3/-7 (except -70) and CF6-45/-50 series engines.
COMPLIANCE See paragraph 1.E., Compliance.
The Federal Aviation Administration (FAA) will possibly release an Airworthiness Directive related to this service bulletin. The Airworthiness Directive will make the compliance tasks and times given in this service bulletin mandatory.
INDUSTRY SUPPORT INFORMATION Boeing warranty remedies are not available for the configuration changes, inspection, and/or repair procedures given in this service bulletin.
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MANPOWER
MATERIAL INFORMATION Boeing Supplied Kits/Parts.
Refer to Paragraph 2.A., Material - Price and Availability.
Airplane Group Configuration Total Task Hours Elapsed Hours 1 1 371.00 134.50 2 78.30 41.30 3 79.00 42.00 2 1 309.00 103.5 2 55.70 30.70 3 56.40 31.40 3 1 337.00 117.50 2 72.30 39.30 3 73.00 40.00
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DO AN OPEN HOLE HIGH
FREQUENCY EDDY CURRENT
INSPECTION OF THE FASTENER
HOLES COMMON TO THE FRONT SPAR CHORD FOR CRACKS.
LEFT INBOARD STRUT SHOWN (OTHER STRUTS SIMILAR)
STRUTS WHICH HAVE NOT PREVIOUSLY INSTALLED THE CAP SKIN DOUBLER________________________________ (INBOARD STRUTS ONLY). REWORK LEADING
EDGE SECTION OR FAIRING TO ACCOMMODATE DOUBLER ISTALLATION.
FRONT SPAR CHORD FRAME
REAR ENGINE MOUNT
BULKHEAD
STRUTS WHICH HAVE NOT PREVIOUSLY INSTALLED THE CAP SKIN DOUBLER________________________________ INSTALL CAP SKIN DOUBLER.
FWD 1544976
October 30, 2008 747-54A2230 BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. 11 of 300
ALERT ALERT Commercial Airplane Group 747
ALERTALERT Service Bulletin Number: 747-54A2230 Date: October 30, 2008 ATA System: 5400 5430 SUBJECT: NACELLES / PYLONS - Front Spar Chord Inspection and Strut Cap Skin Installation
THIS BULLETIN IS SENT TO THE OPERATORS OF RECORD OF THE AIRPLANES SHOWN IN PARAGRAPH 1.A., EFFECTIVITY. IF AN AIRPLANE HAS BEEN LEASED OR SOLD, SEND THIS SERVICE BULLETIN TO THE NEW OPERATOR. IF APPLICABLE SPARES HAVE BEEN SOLD, SEND THIS SERVICE BULLETIN TO THE NEW OWNER.
1. PLANNING INFORMATION A. Effectivity
1. Airplanes Refer to Service Bulletin Index Document D6-30300 Part 3 for Airplane Variable Number, Line Number, and Serial Number data.
This service bulletin is for the airplanes shown below.
GROUP CONFIGURATION DESCRIPTION 1 - 747-100, -100B, -100SUD, -200B, -200C, - 200F, -300, -SP, and -SR airplanes powered by JT9D-3/-7 (except-70) series engines.
1 Airplanes which have not incorporated Service Bulletin 747-54-2125.
2 Airplanes which installed the strut cap skin doubler in accordance with Service Bulletin 747- 54-2125 Original Issue or Revision 1.
3 Airplanes which installed the strut cap skin doubler in accordance with 747-54-2125 Revision 2 or later releases.
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Airplane models:
747-100 747-100B 747-100B SUD 747-200B 747-200C 747-200F 747-300 747SP 747SR
IDENTIFICATION BY CUSTOMER, CUSTOMER CODE, GROUP AND VARIABLE NUMBER AAR A/C ENG. SALES & LEASING (AFD) 2 RB681–RB682
AERO CONTROLS (AEO) 1 RA722–RA723
AEROLINEAS ARGENTINAS (ARG) 1 RD122–RD127 AFRICA UNITED HOLDING CO. (UHD) 1 RB010 RD513
AFX (AXL) 1 RD201
AGES AIRCRAFT SALES & LEASING (AGJ) 1R B 0 0 4 2 - 747-200B, -200C, -200F, -300, and -SR airplanes powered by CF6-45/-50 series engines.
1 Airplanes which have not incorporated Service Bulletin 747-54-2125.
2 Airplanes which installed the strut cap skin doubler in accordance with Service Bulletin 747- 54-2125 Original Issue or Revision 1.
3 Airplanes which installed the strut cap skin doubler in accordance with 747-54-2125 Revision 2 or later releases.
3 - 747-200B airplanes powered by CF6-45/-50 series engines with modified JT9D-3/-7 inboard struts.
1 Airplanes which have not incorporated Service Bulletin 747-54-2125.
2 Airplanes which installed the strut cap skin doubler in accordance with Service Bulletin 747- 54-2125 Original Issue or Revision 1.
3 Airplanes which installed the strut cap skin doubler in accordance with 747-54-2125 Revision 2 or later releases.