### Commercial **Airplanes** 

# 707 Service Bulletin **ALERT Number: A3515**  Original Issue: December 19, 2007 Revision 1: October 10, 2014 ATA System: 5510 **SUBJECT:** STABILIZERS - Horizontal Stabilizer - Rear Spar Upper and Lower Chords - 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 © 2007 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 Unpublished Work.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: December 19, 2007 A3515 Revision 1: October 10, 2014 1 of 38 10.0Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: December 19, 2007 A3515 Revision 1: October 10, 2014 2 of 38 **BOEING SERVICE BULLETIN A3515 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 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15 B. Concurrent Requirements. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15 C. Reason. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15 D. Description. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16 E. Compliance. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16 F. Approval . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20 G. Manpower . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20 H. Weight and Balance Changes. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21 I. Electrical Load Data. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21 J. References. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21 1. Existing Data: . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21 2. Data Supplied with this Service Bulletin:. . . . . . . . . . . . . . . . . . . . . . . . . . . 22 3. Installation Drawings Used in the Preparation of this Service Bulletin:. . . . . . . . . . . 22 K. Publications Affected . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22 L. Interchangeability and Intermixability of Parts. . . . . . . . . . . . . . . . . . . . . . . . . . . 22 M. Software Accomplishment Summary. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22 2. MATERIAL INFORMATION. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23 A. Material - Price and Availability. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23 B. Industry Support Information. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23 C. Parts Necessary for Each Airplane. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23 1. Kits/Parts: . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23 2. Parts and Materials Supplied by the Operator:. . . . . . . . . . . . . . . . . . . . . . . . 23 3. Parts Modified and Reidentified:. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24 4. Parts Removed and Not Replaced:. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24 D. Parts Necessary to Change Spares. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24 E. Special Tooling - Price and Availability. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24 F. Special Tooling Necessary to do this Service Bulletin. . . . . . . . . . . . . . . . . . . . . . . 24 3. ACCOMPLISHMENT INSTRUCTIONS. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25 A. GENERAL INFORMATION. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25 B. WORK INSTRUCTIONS. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26 FIGURE 1: HORIZONTAL STABILIZER - REAR SPAR - UPPER AND LOWER - INBOARD AND OUTBOARD - CHORD WEB FLANGE - STABILIZER STATION 92.55 TO STABILIZER STATION 272.55 - INSPECTION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31 FIGURE 2: HORIZONTAL STABILIZER - REAR SPAR - UPPER OUTBOARD CHORD - FORWARD SKIN FLANGE - STABILIZER STATION 182.55 TO STABILIZER STATION 272.55 - INSPECTION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33 FIGURE 3: HORIZONTAL STABILIZER - REAR SPAR - UPPER INBOARD CHORD - FORWARD SKIN FLANGE - STABILIZER STATION 92.55 TO STABILIZER STATION 182.55 - INSPECTION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34

Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: December 19, 2007 A3515 Revision 1: October 10, 2014 3 of 38 **BOEING SERVICE BULLETIN A3515 ALERT**  **ALERT**FIGURE 4: HORIZONTAL STABILIZER - REAR SPAR - LOWER OUTBOARD CHORD - FORWARD SKIN FLANGE - STABILIZER STATION 182.55 TO STABILIZER STATION 272.55 - INSPECTION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35 FIGURE 5: HORIZONTAL STABILIZER - REAR SPAR - LOWER INBOARD CHORD - FORWARD SKIN FLANGE - STABILIZER STATION 92.55 TO STABILIZER STATION 182.55 - INSPECTION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36 FIGURE 6: HORIZONTAL STABILIZER - REAR SPAR - LOWER INBOARD CHORD - FORWARD SKIN FLANGE - STABILIZER STATION -13.179 TO STABILIZER STATION 92.55 - INSPECTION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37 Appendix A: CONFIGURATION VERIFICATION - INSPECTION RESULTS FORM - MATERIAL DATA . 38

Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: December 19, 2007 A3515 Revision 1: October 10, 2014 4 of 38 **BOEING SERVICE BULLETIN A3515 ALERT**  **ALERT**

### Commercial **Airplanes** 

# 707 Service Bulletin **ALERT Revision Transmittal Sheet**  **Number: A3515** Original Issue: December 19, 2007 Revision 1: October 10, 2014 ATA System: 5510 **SUBJECT:** STABILIZERS - Horizontal Stabilizer - Rear Spar Upper and Lower Chords - Inspection and Repair This revision includes all pages of the service bulletin. **COMPLIANCE INFORMATION RELATED TO THIS REVISION** Federal Aviation Administration (FAA) Airworthiness Directives AD 2012-17-13 and AD 85-12-01 R1 are related to this service bulletin. No more work is necessary on the airplane(s) changed in accordance with the original issue of this service bulletin. **REASON FOR REVISION** This revision is sent to updated compliance table and wording to clarify requirements, provide clarifying information for the Compliance requirements for the Part 6 7079 aluminum chord replacement with 7075 aluminum chords, to clarify Parts 3, 4 & 5 by removing unnecessary redundant wording, and to add reference to Federal Aviation Administration (FAA) Airworthiness Directive AD 2012-17-13. These sections were changed: 1. Summary, Background, added clarifying information for the Part 6 7079 aluminum chord replacement with 7075 aluminum chords. 2. Summary, Compliance, added FAA Airworthiness Directives AD 2012-17-13 and AD 85-12-01 R1. 3. Paragraph 1.C., Reason, added clarifying information for the Part 6 7079 aluminum chord replacement with 7075 aluminum chords. 4. Paragraph 1.E., Compliance, updated compliance table to clarify requirements, added clarifying information for the Part 6 7079 aluminum chord replacement with 7075 aluminum chords and added FAA Airworthiness Directives AD 2012-17-13 and AD 85-12-01 R1. 5. Paragraph 1.F., Approval, added FAA Airworthiness Directive AD 2012-17-13. 6. Paragraph 1.J., References, added FAA Airworthiness Directives AD 85-12-01 R1 and AD 2012-17-13. 7. Paragraph 2.C.2., Parts and Materials Supplied by the Operator, removed footnote (c) and added parts 65-95600-703 and 65-95600-704 and footnotes (j) and (k).

Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: December 19, 2007 A3515 Revision 1: October 10, 2014 5 of 388. Paragraph 3.B.3., Work Instructions, removed unnecessary redundant wording. 9. Paragraph 3.B.4., Work Instructions, removed unnecessary redundant wording. 10. Paragraph 3.B.5., Work Instructions, removed unnecessary redundant wording. 11. Paragraph 3.B.6., Work Instructions, added clarifying information for the Part 6 7079 aluminum chord replacement with 7075 aluminum chords. 12. Paragraph 3.B., Work Instructions, Figures 1 through 6 and Appendix A, changed all NDT callouts to "in accordance with". 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** December 19, 2007 Original Issue: October 10, 2014 Revision 1:

Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: December 19, 2007 A3515 Revision 1: October 10, 2014 6 of 38 **BOEING SERVICE BULLETIN A3515 ALERT**  **ALERT**

### Commercial **Airplanes** 

# 707 Service Bulletin **ALERT Summary**  **Number: A3515** Original Issue: December 19, 2007 Revision 1: October 10, 2014 ATA System: 5510 **SUBJECT:** STABILIZERS - Horizontal Stabilizer - Rear Spar Upper and Lower Chords - 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** Boeing Service Related Problem (SRP) 707-SRP-55-0033 is related to this service bulletin. 1. ISSUE 1 - Stress Corrosion Cracking in Chords Made from 7079 Aluminum in the Horizontal Stabilizer Rear Spar Boeing has received numerous reports of stress corrosion cracking in the chord segments made from 7079 aluminum in the 707 horizontal stabilizer rear spar This is a material that is known to be susceptible to stress corrosion cracking. Early reports led to Boeing Service Bulletins 707-3356 and 707-3381. Incorporation of the modifications in those service bulletins has helped to slow the development of stress corrosion cracks. Boeing Service Bulletin 707-A3515 continues the inspections of 707-3356 and 707-3381, but at shorter intervals, and in concurrence with the necessary actions that are the subject of Issue 2 below, until the 7079 aluminum chord segments are replaced by ones made from 7075. The actions of this service bulletin addressing Issue 1 are necessary to adequately detect development of stress corrosion cracking in 7079 aluminum chords. 2. ISSUE 2 - Early Fatigue Cracking in the Inboard Segment of the Upper Chord in the Horizontal Stabilizer Rear Spar Boeing has received three reports of fatigue cracking in the upper chord of the horizontal stabilizer rear spar at a location near the side of the body. In all cases the fatigue prevention and fail safety improvement modifications of Boeing Service Bulletin 707-A3313 had been incorporated. The fatigue cracking is considered to be early in the life of the modified structure. The fatigue cracks are generated by frequent use of the airplanes for training flights that include multiple Touch and Goes. This frequent use of the airplane for this type of training has been most prevalent with military operators of commercial model 707 and 720 airplanes. The actions of this service bulletin are necessary to adequately detect early fatigue cracking.

Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: December 19, 2007 A3515 Revision 1: October 10, 2014 7 of 383. CONFIGURATION The ability to move the horizontal stabilizer to a different airplane is of significance to Issue 1 and Issue 2. Parts made from 7079 have been discovered on airplanes not originally delivered with those parts. Therefore, to adequately address Issue 1, it is necessary to determine the horizontal stabilizer rear spar chord configuration on the airplane. It is also necessary to carefully maintain a record of that configuration until all 7079 horizontal stabilizer rear spar chord segments have been removed from the fleet. Regarding Issue 2, since horizontal stabilizers can be moved to different airplanes, it is necessary to implement the inspections for early fatigue cracking on all effective airplanes at the time stated in the 1.E Compliance section, regardless of the current usage of the airplane. **ACTION (PRR 18101-2RS)** Cycle Definition: To adequately account for in-flight training maneuvers, incorporate the cycle counting procedure defined in this service bulletin. Configuration Check: To Maintain configuration identity, determine the material for each horizontal stabilizer rear spar chord segment addressed by this service bulletin. Maintain the configuration identity indefinitely. Inspections: Complete the inspections for stress corrosion cracking and fatigue cracking in accordance with the methods and times stated in this service bulletin. Repair: Contact Boeing for repair instructions or replace the cracked part with a spare part made from 7075 aluminum. **EFFECTIVITY** All 707-300, 707-300B, 707-300C and 707-400 Airplanes. See Paragraph 1.A.1 for effectivity. **COMPLIANCE** Federal Aviation Administration (FAA) Airworthiness Directives AD 2012-17-13 and AD 85-12-01 R1 are related to this service bulletin. See Service Bulletin Paragraph 1.E. for compliance information. **INDUSTRY SUPPORT INFORMATION** Boeing warranty remedies are not available for the inspection and/or repair procedures given in this service bulletin. **MANPOWER** See Service Bulletin Paragraph 1.G. for manpower information. **MATERIAL INFORMATION** Operator Supplied Parts/Materials. Refer to Paragraph 2.A., Material - Price and Availability.

Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: December 19, 2007 A3515 Revision 1: October 10, 2014 8 of 38 **BOEING SERVICE BULLETIN A3515 ALERT**  **ALERT**Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: December 19, 2007 A3515 Revision 1: October 10, 2014 9 of 38 **BOEING SERVICE BULLETIN A3515 ALERT**  **ALERT**Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: December 19, 2007 A3515 Revision 1: October 10, 2014 10 of 38 **BOEING SERVICE BULLETIN A3515 ALERT**  **ALERT**

BLANK PAGE

### Commercial **Airplanes** 

# 707 Service Bulletin **ALERT Number: A3515**  Original Issue: December 19, 2007 Revision 1: October 10, 2014 ATA System: 5510 **SUBJECT:** STABILIZERS - Horizontal Stabilizer - Rear Spar Upper and Lower Chords - 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 for the airplanes shown below. An equivalent change is on subsequent production airplanes. Refer to PRR 18101-2RS for data about this change. Refer to Service Bulletin Index Document D6-1647 Part 3 for Airplane Variable Number, Line Number, and Serial Number data.
**DESCRIPTION CONFIGURATION**  **GROUP** All horizontal stabilizer rear spar chords made from 7079-T6.

- 1 Horizontal stabilizer rear spar upper inboard and upper outboard chords made of 7079-T6. - 2

Left side horizontal stabilizer rear spar upper inboard chords made from 7079-T6. - 3

All horizontal stabilizer rear spar chords made from 7075-T73511.

- 4

Airplane Models: 707-300, 707-300B, 707-300C, 707-400

Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: December 19, 2007 A3515 Revision 1: October 10, 2014 11 of 38**Group Variable Number**  1 02001 - 02020 1 02101 - 02121 1 02201 - 02207 1 02301 - 02303 1 02401 - 02418 1 04001 - 04005 1 04020 - 04022 1 04101 - 04106 1 04201 - 04218 1 04271 - 04272 1 04301 - 04303 1 05001 - 05060 1 05101 - 05138 1 05201 - 05208 1 05301 - 05312 1 05401 1 05601 - 05605 1 05631 - 05635 1 05701 - 05703 1 05801 - 05802 1 05821 - 05827 1 05831 - 05833 1 05851 - 05854 1 05891 - 05892 1 05921 - 05923 1 05941 - 05942 1 05961 - 05970 1 06001 - 06002 1 06101 1 06401 - 06404 4 06451 4 06461

Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: December 19, 2007 A3515 Revision 1: October 10, 2014 12 of 38 **BOEING SERVICE BULLETIN A3515 ALERT**  **ALERT Group**  **Variable Number** 1 07001 - 07017 1 07041 - 07059 1 07071 - 07081 1 07101 - 07109 1 07181 1 07191 1 07201 - 07208 1 07210 1 07212 - 07215 1 07251 - 07271 1 07401 - 07407 1 07451 - 07458 1 07501 - 07504 1 07601 - 07626 1 07661 - 07662 1 07681 - 07684 1 07701 - 07702 1 07801 - 07821 1 07901 - 07907 1 08001 - 08008 1 08021 1 08051 - 08056 1 08071 - 08077 1 08101 - 08104 1 08121 - 08129 1 08141 - 08144 1 08151 - 08153 1 08171 - 08173 1 08191 - 08192 1 08201 - 08208 3 08209 - 08210 1 08221 - 08224 1 08241 - 08244

Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: December 19, 2007 A3515 Revision 1: October 10, 2014 13 of 38 **BOEING SERVICE BULLETIN A3515 ALERT**  **ALERT Group**  **Variable Number** 1 08251 1 08261 1 08271 1 08301 - 08320 1 08324 - 08330 1 08333 1 08401 - 08410 1 08451 - 08452 1 08471 - 08475 1 08501 - 08502 1 08551 - 08553 1 08581 - 08582 1 09001 - 09006 1 09101 - 09102 3 09103 - 09105 4 09106 - 09107 4 09161 - 09167 1 09201 - 09202 2 09203 4 09204 3 09221 - 09223 4 09227 2 09231 3 09232 4 09251 4 09271 4 09281 4 09286 - 09290 4 09411 4 09421 4 09438 4 09441

Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: December 19, 2007 A3515 Revision 1: October 10, 2014 14 of 38 **BOEING SERVICE BULLETIN A3515 ALERT**  **ALERT**2. Spares Affected None. **B. Concurrent Requirements** None. **C. Reason** Boeing Service Related Problem (SRP) 707-SRP-55-0033 is related to this service bulletin. 1. ISSUE 1 - Stress Corrosion Cracking in Chords made from 7079 Aluminum in the Horizontal Stabilizer Rear Spar Boeing has received numerous reports of stress corrosion cracking in the chord segments made from 7079 aluminum in the 707 horizontal stabilizer rear spar. This is a material that is known to be susceptible to stress corrosion cracking. Early reports led to Boeing Service Bulletins 707-3356 and 707-3381. Incorporation of the modifications in those service bulletins has helped to slow the development of stress corrosion cracks. Boeing Service Bulletin 707-A3515 continues the inspections of 707-3356 and 707-3381, but at shorter intervals, and in concurrence with the necessary actions that are the subject of Issue 2 below, until the 7079 aluminum chord segments are replaced by ones made from 7075. The actions of this service bulletin addressing Issue 1 are necessary to adequately detect development of stress corrosion cracking in 7079 aluminum chords. 2. ISSUE 2 - Early Fatigue Cracking in the Inboard Segment of the Upper Chord in the Horizontal Stabilizer Rear Spar Boeing has received three reports of fatigue cracking in the upper chord of the horizontal stabilizer rear spar at a location near the side of the body. In all cases the fatigue prevention and fail safety improvement modifications of Boeing Service Bulletin 707-A3313 had been incorporated. The fatigue cracking is considered to be early in the life of the modified structure. The fatigue cracks are generated by frequent use of the airplanes for training flights that include multiple Touch and Goes. This frequent use of the airplane for this type of training has been most prevalent with military operators of commercial model 707 and 720 airplanes. The actions of this service bulletin are necessary to adequately detect early fatigue cracking. 3. CONFIGURATION The ability to move the horizontal stabilizer to a different airplane is of significance to Issue 1 and Issue 2. Parts made from 7079 have been discovered on airplanes not originally delivered with those parts. Therefore, to adequately address Issue 1, it is necessary to determine the horizontal stabilizer rear spar chord configuration on the airplane. It is also necessary to carefully maintain a record of that configuration until all 7079 horizontal stabilizer rear spar chord segments have been removed from the fleet. Regarding Issue 2, since horizontal stabilizers can be moved to different airplanes, it is necessary to implement the inspections for early fatigue cracking on all effective airplanes at the time stated in the 1.E Compliance section, regardless of the current usage of the airplane.

Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: December 19, 2007 A3515 Revision 1: October 10, 2014 15 of 38 **BOEING SERVICE BULLETIN A3515 ALERT**  **ALERT**Revision 1 is sent to updated compliance table and wording to clarify requirements, provide clarifying information for the Compliance requirements for the Part 6 7079 aluminum chord replacement with 7075 aluminum chords, to clarify Parts 3, 4 & 5 by removing unnecessary redundant wording, and to add reference to Federal Aviation Administration (FAA) Airworthiness Directive AD 2012-17-13. **D. Description** Cycle Definition: To adequately account for in-flight training maneuvers, incorporate the cycle counting procedure defined in this service bulletin. Configuration Check: To Maintain configuration identity, determine the material for each horizontal stabilizer rear spar chord segment addressed by this service bulletin. Maintain the configuration identity indefinitely. Inspections: Complete the inspections for stress corrosion cracking and fatigue cracking in accordance with the methods and times stated in this service bulletin. Repair: Contact Boeing for repair instructions or replace the cracked part with a spare part made from 7075 aluminum. Revision 1 - No more work is necessary on airplanes changed in accordance with the original issue of this service bulletin. The work in this service bulletin is done in the maintenance zone(s) given below. **Group 1:**
**Affected Maintenance Zones Zone**  **Model** 3-93, 3-94 707-300, 707-300B, 707-300C, 707-400 **Group 2-3:**
**Affected Maintenance Zones Zone**  **Model** 3-93, 3-94 707-300C **Group 4:**
**Affected Maintenance Zones Zone**  **Model** 3-93, 3-94 707-300B, 707-300C **E. Compliance** Federal Aviation Administration (FAA) Airworthiness Directives AD 2012-17-13 and AD 85-12-01 R1 are related to this service bulletin.

Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: December 19, 2007 A3515 Revision 1: October 10, 2014 16 of 38 **BOEING SERVICE BULLETIN A3515 ALERT**  **ALERT**Boeing recommends the following: Applicable to all rear spar chord segments (upper inboard, upper outboard, lower inboard, lower outboard and center) made from 7079, do the Part 6 - Chord Replacement within 48 months after the Revision 1 date of this service bulletin. **Table 1: Determine Flight Cycles and Material of Horizontal Stabilizer Rear Spar Chord Segments Repeat Interval**  **(Not to Exceed) Compliance Time**  **Action Condition** 

- At time of original service bulletin release. Determine flight cycles as given in Accomplishment Instructions paragraph 3.B.1. Part 1. All airplanes

180 calendar days or 250 flight cycles, whichever occurs first. (a) Within 180 calendar days after the original release date of this service bulletin. Determine material of the left and right side horizontal stabilizer rear spar chord segments as given in Accomplishment Instructions Paragraph 3.B.2. Part 2. (c) All airplanes

N/A Before further flight following the horizontal stabilizer replacement. Airplanes on whichthe horizontal stabilizer is being replacedwith a different horizontal stabilizer.

- - Inspect and repair the horizontalstabilizer rear spar chord segments made from 7075 as given in Table 2. (b) (c)Airplanes with horizontal stabilizer rear spar chord segments made from 7075 asfound in the Accomplishment Instructions Paragraph 3.B.2 Part 2. (c)

- - Inspect and repair the horizontalstabilizer rear spar chord segments made from 7079 as given in Table 3. (b) (c)Airplanes with horizontal stabilizer rear spar chord segments made from 7079 asfound in the Accomplishment Instructions Paragraph 3.B.2 Part 2. (c) (a) See Part 1 - Cycle Counting Procedure for definition of "cycles." (b) If you have a mixture of 7075 chord segments and 7079 chord segments, use Tables 2 and 3. (c) Spar chord segments are as defined in APPENDIX A.

Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: December 19, 2007 A3515 Revision 1: October 10, 2014 17 of 38 **BOEING SERVICE BULLETIN A3515 ALERT**  **ALERT Table 2: Inspect and Repair Horizontal Stabilizer Rear Spar Upper Inboard Chord Segments Made From**  **7075 Material Repeat Interval**  **(Not to Exceed) Compliance Time**  **Action Condition**  500 flight cycles. (a) Within 180 calendar days or 500flight cycles after the original release date of this service bulletin, whichever occurs first. (a) (c)Inspect and repair the upper inboard chord segment from stabilizer station -13.179 to 92.55 asgiven in Accomplishment Instructions Paragraph 3.B.3. Part 3. (d)Airplanes with horizontal stabilizer rear spar upper inboard chord segment made from 7075. (d) N/A Before further flight following the horizontal stabilizer replacement. (c) Airplanes on whichthe horizontal stabilizer is being replacedwith a different horizontal stabilizer having the upper inboard chord segment made from 7075. (d) 500 flight cycles. (a) Within 4000 flight cycles after thedate of upper chord inboard segment replacement. (a) (d)Inspect and repair the upper inboard chord segment from stabilizer station -13.179 to 92.55 asgiven in Accomplishment Instructions Paragraph 3.B.3. Part 3. (b) (d) Airplanes on whichthe horizontal stabilizer rear spar upper inboard chord segment is replaced as given in AccomplishmentInstructions Paragraph 3.B.6 Part 6. (d) (a) See Part 1 - Cycle Counting Procedure for definition of "cycles." (b) Continued inspections are only necessary for rear spar upper inboard chord segments made from 7075. Continued inspections are not necessary for other spar chord segments replaced with 7075 parts. (c) When you replace the rear spar upper inboard chord segment as given in Accomplishment Instructions Paragraph 3.B.6 Part 6, you can defer that chord segment inspection given in Accomplishment Instructions Paragraph 3.B.3. Part 3 for a maximum of 4,000 flight cycles. (d) Spar chord segments are as defined in APPENDIX A. **Table 3: Inspect and Repair Horizontal Stabilizer Rear Spar Upper and Lower Chord Segments Made From 7079 Material**  **Repeat Interval (Not to Exceed)**  **Compliance Time Action**  **Condition**

180 calendar days or 250 flight cycles, whichever occurs first. (a) Within 180 calendar days or 250flight cycles after the original release date of this service bulletin, whichever occurs first. (a)Inspect and repair the upper inboard chord segment from stabilizer station -13.179 to 92.55 asgiven in Accomplishment Instructions Paragraph 3.B.3. Part 3. (c)Airplanes with horizontal stabilizer rear spar upper inboard chord segment made from 7079. (c)

Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: December 19, 2007 A3515 Revision 1: October 10, 2014 18 of 38 **BOEING SERVICE BULLETIN A3515 ALERT**  **ALERT Table 3: Inspect and Repair Horizontal Stabilizer Rear Spar Upper and Lower Chord Segments Made**  **From 7079 Material Repeat Interval**  **(Not to Exceed) Compliance Time**  **Action Condition** 

180 calendar days or 1000 flight cycles, whichever occurs first. (a) Within 180 calendar days or 1000flight cycles after the original release date of this service bulletin, whichever occurs first. (a) Inspect and repair the web flanges of the rear spar upper and lower chord segments made from 7079, from stabilizer station 92.55to 272.55 as given in Accomplishment Instructions Paragraph 3.B.4. Part 4. (b) (c) Airplanes with any ofthe following horizontal stabilizer rear spar chord segments made from 7079: upper inboard, upperoutboard, lower inboard, lower outboard. (c) Inspect and repair the forwardskin flanges of the rear spar upper and lower chord segments made from 7079, from stabilizer station -13.179 to 272.55 as given in Accomplishment Instructions Paragraph 3.B.5. Part 5. (b) (c) N/A Before further flight following the horizontal stabilizer replacement. (c)Do the Part 6 - Chord Replacement, for all rear spar chord segments made from 7079. (c) Airplanes on whichthe horizontal stabilizer is being replacedwith a different horizontal stabilizer having rear spar chord segments made from 7079. (c)

- Before further flight. Do Boeing service bulletin 707-3381 Part II - Preventative Modification as given in Accomplishment Instructions Paragraphs 3.B.4 Part 4 and 3.B.5 Part 5 orreplace the chord as given in Accomplishment Instructions Paragraph 3.B.6 Part 6.Airplanes with horizontal stabilizers that have rear spar chord segments made from 7079 for which the Service Bulletin 707-3381 Part II - Preventative Modification is not completed. (c) (a) See Part 1 - Cycle Counting Procedure for definition of "cycles."(b) Only those chord segments made from 7079 material require the inspection and repair given in the Accomplishment Instructions Paragraphs 3.B.4. Part 4 and 3.B.5. Part 5. Chord segments made from 7075 material do not require the inspection and repair given in the Accomplishment Instructions Paragraphs 3.B.4. Part 4 and 3.B.5. Part 5. (c) Spar chord segments are as defined in APPENDIX A.

Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: December 19, 2007 A3515 Revision 1: October 10, 2014 19 of 38 **BOEING SERVICE BULLETIN A3515 ALERT**  **ALERT 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. The Part 3 inspections of this service bulletin supersede and replace the 707 Supplemental Structural Inspection Document (SSID) inspections 55-A25-03, 55-A35-03 and 55-A45-03 mandated by Paragraph A of AD 85-12-01 R1. The inspections contained in this service bulletin have been reviewed and approved by the Manager of the FAA Seattle Aircraft Certification Office as an alternative method of compliance to the requirements of Paragraph A of AD 85-12-01 R1 for SSID items 55-A25-03, 55-A35-03 and 55-A45-03 covered by this service bulletin. All other provisions of AD 85-12-01 R1 that are not specifically referenced above remain fully applicable and must be complied with. In addition, the Manager of the FAA Seattle Aircraft Certification Office approves the flight cycle counting procedures, inspections or modifications defined in this service bulletin as an alternative method of compliance to the requirements of paragraphs (g), (h), (i), (j), (k), (l), and (m) of AD 2012-17-13 pertaining to Boeing Alert Service Bulletin 707 A3515, dated December 19, 2007. When the service bulletin specifies contacting Boeing for repair instructions, the repair must be approved by the FAA in accordance with paragraph (n) of the AD. All provisions of AD 2012-17-13 that are not specifically referenced in this paragraph remain fully applicable and must be complied with accordingly. **G. Manpower** The table below shows an estimate of the task-hours necessary to do this service bulletin for each airplane. This estimate is for direct labor only, done by an experienced crew. Adjust the estimate with operator task-hour data if necessary. The estimate does not include lost time. These are some examples of lost time: — Time to adjust to the workplace — Time to schedule the work — Time to examine the work — Time to cure the materials — Time to make the parts — Time to find the tools. **Elapsed Hours Task Hours**  **Number of Per- sons**  **Task**

0.5 1.0 2 Open Access (a) (a)

- Part 1 0.5(b) 1.0(b) 2 Part 2 6.5 26.0 4 Part 3

Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: December 19, 2007 A3515 Revision 1: October 10, 2014 20 of 38 **BOEING SERVICE BULLETIN A3515 ALERT**  **ALERT Elapsed Hours**  **Task Hours Number of Per-**  **sons Task** 

8.0 32.0 4 Part 4 6.0 24.0 4 Part 5 (c) (c) (c) Part 6 0.5 1.0 2 Close Access (d) (d) TOTAL FOR EACH AIRPLANE (a) Considered Lost Time. Not able to estimate. (b) Covers conductivity test only, does not include maintenance record review. (c) No estimate is available. (d) No total is given because of the variability in time required for Part 1, Part 2 and Part 6 activities. **H. Weight and Balance Changes** None. **I. Electrical Load Data** Not applicable. **J. References** 1. Existing Data: a. Engineering Change Memo PRR 18101-2RS b. Boeing Service Bulletin 707-3356, 707-3381 c. Service Related Problem (SRP) 707-SRP-55-0033. d. 707 Supplemental Structural Inspection Document (SSID) D6-44860, Revision P, Item 55-A25-03, 55-A35-03 and 55-A45-03. e. Federal Aviation Administration (FAA) Airworthiness Directive (AD) 2012-17-13, 85-12-01 R1 f. Standard Overhaul Practices Manual (SOPM) 20-41-05 g. Standard Wiring Practices Manual (SWPM) 20-10-11, 20-10-12, 20-10-12, 20-10-19 h. 707, 720 Non-Destructive Testing (NDT) Manual Part 1, 51-01-00, Part 6, 51-00-00, Part 6, 55-10-07 i. 707 Aircraft Maintenance Manual (AMM) 27-07-31

Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: December 19, 2007 A3515 Revision 1: October 10, 2014 21 of 38 **BOEING SERVICE BULLETIN A3515 ALERT**  **ALERT**2. Data Supplied with this Service Bulletin: None. 3. Installation Drawings Used in the Preparation of this Service Bulletin: None. **K. Publications Affected** None. **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: December 19, 2007 A3515 Revision 1: October 10, 2014 22 of 38 **BOEING SERVICE BULLETIN A3515 ALERT**  **ALERT 2. MATERIAL INFORMATION**  **A. Material - Price and Availability** None. **B. Industry Support Information** Boeing warranty remedies are not available for the inspection procedures given in this service bulletin. **C. Parts Necessary for Each Airplane** 1. Kits/Parts: None. 2. Parts and Materials Supplied by the Operator:
**Notes Name**  **QTY Part Number / Specification**  (a) (d) Upper Chord, Inboard, Left Side 1 65-95600-887 (a) (e) Upper Chord, Inboard, Right Side 1 65-95600-888 (a) (f) Lower Chord, Inboard, Left Side 1 65-95600-701 (a) (g) Lower Chord, Inboard, Right Side 1 65-95600-702 (a) (j) Center Rear Spar, Left Side 1 65-95600-703 (a) (k) Center Rear Spar, Right Side 1 65-95600-704 (a) (h) Upper Chord, Outboard, Left Side 1 65C80665-165 (a) (h) Lower Chord, Outboard, Right Side 1 65C80665-165 (a) (i) Lower Chord, Outboard, Left Side 1 65C80665-166 (a) (i) Upper Chord, Outboard, Right Side 1 65C80665-166 (b) Corrosion Inhibiting compound 1 Pint BMS 3-23 Type II (a) Discard the existing part. (b) See the Qualified Products List at the end of the Boeing Material Specification (BMS) for supplier data. (c) This note has been deleted. (d) 65-95600-887 is the same as 65-3321-27 plus two 66-11433-4 bushings. (e) 65-95600-888 is the same as 65-3321-28 plus two 66-11433-4 bushings. (f) 65-95600-701 is the same as 65-3322-15 plus two 69-38158-1 bushings plus two 69-38158-2 bushings. (g) 65-95600-702 is the same as 65-3322-16 plus two 69-38158-1 bushings plus two 69-38158-2 bushings. (h) 65C80665-165 is the same as 65-05201-3. (i) 65C80665-166 is the same as 65-05201-4. (j) 65-95600-703 is the same as 65-3323-27 plus two 66-11433-2 bushings.

Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: December 19, 2007 A3515 Revision 1: October 10, 2014 23 of 38 **BOEING SERVICE BULLETIN A3515 ALERT**  **ALERT Notes**  **Name QTY**  **Part Number / Specification** (k) 65-95600-704 is the same as 65-3323-28 plus two 66-11433-2 bushings.
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** The operator can supply the tools shown in Paragraph 2.F., Special Tooling Necessary to do this Service Bulletin. Tool price and supply data are not given. **F. Special Tooling Necessary to do this Service Bulletin** See 707, 720 NDT Manual Part 1, 51-01-00. – 8MIT65-6088 – 9MIT65-6088

Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: December 19, 2007 A3515 Revision 1: October 10, 2014 24 of 38 **BOEING SERVICE BULLETIN A3515 ALERT**  **ALERT 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 limits to tighten nuts and bolts are in SRM Chapter 51 4. Use the approved fastener and process material substitutions in accordance with SRM Chapter 51. Alternate fasteners are listed in SRM Chapter 51. 5. Refer to the SWPM 20-10-11 and SWPM 20-10-12 for the wire installation procedures, and SWPM 20-10-19 for the wire separation requirements, as accepted procedures. 6. The necessary conditions for selection of clamp type and size are included in SWPM 20-10-12. If any wire bundle support clamp specified in this service bulletin does not make a correct fit on the wire bundle, refer to SWPM 20-10-12 as an accepted procedure to select a clamp that fits correctly. 7. If the length of any fastener specified in this service bulletin does not meet installation standards given in SRM Chapter 51, then a fastener of the same specification, or an approved substitute, with a length which meets the installation standards given in SRM Chapter 51 may be used. In addition, washers may be installed for fastener grip length in accordance with SRM Chapter 51. 8. 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. 9. Boeing Service Letter 707-SL-51-029 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.

Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: December 19, 2007 A3515 Revision 1: October 10, 2014 25 of 38 **BOEING SERVICE BULLETIN A3515 ALERT**  **ALERT**10. Refer to APPENDIX A, for configuration verification, inspection, material data results form.. 11. 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. 12. 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. 13. 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. The removed part can be discarded if a new or serviceable part is installed. 14. This service bulletin includes functional test procedures for the systems changed by this service bulletin. More functional tests can possibly be necessary in accordance with standard maintenance practices because of interruption to other airplane systems. 15. Some Boeing parts are supplied in a temporary configuration. Those parts are identified with a 'U', 'W', or 'Y' in place of the '-' (dash) in the part number. It is permitted to install parts identified with a 'U', 'W', or 'Y' as an alternative to the '-' (dash) part number. Boeing Drawing 005W0900 contains more data. **B. WORK INSTRUCTIONS** 1. Part 1 - Cycle Counting Procedure a. Determine flight cycles. **NOTE:** The term "flight cycle" wherever stated in this bulletin is defined as any one of the following: 1. A complete flight cycle (takeoff and full stop landing). 2. Any touch-and-go cycle within a flight cycle for which the airplane makes a runway approach, with or without runway contact. 2. Part 2 - Configuration Records Inspection a. Refer to APPENDIX A for definition of the inboard and outboard segments of the left and right horizontal stabilizer rear spar upper and lower chords. Determine the material of all of the spar chord segments listed in APPENDIX A using one of the following methods. (1) Review the airplanes maintenance records or the previously completed APPENDIX A data sheet to identify the location of the upper and lower chords on the horizontal stabilizer rear spar that are made from 7079. If the material cannot be conclusively determined, do step (2).

Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: December 19, 2007 A3515 Revision 1: October 10, 2014 26 of 38 **BOEING SERVICE BULLETIN A3515 ALERT**  **ALERT**(2) Do a conductivity test to determine whether each upper chord and lower chord segment on the horizontal stabilizer rear spar listed in APPENDIX A is made from 7079-T6 or 7075-T73511 material in accordance with 707, 720 NDT, Part 6, 51-00-00, Figure 20, dated April 5, 2004. b. Optional. (1) Record the material of each upper chord and lower chord segment on the APPENDIX A data sheet. Describe any existing repairs in the "Comments" field. (2) Retain the APPENDIX A data sheet with the airplane records. 3. Part 3 - Chord Inspection - Horizontal Stabilizer - Rear Spar - Inboard - Upper Chord - Stabilizer Station -13.179 to 92.55. **Upper Chords, Horizontal Stabilizer Rear Spar, Inboard Segment, Made From 7075 and 7079** a. Do a special detailed inspection of the upper chord. (1) Inspect for cracks in the forward flange of the chord along the fasteners common to the skin. Inspect from the inboard edge of the inspar skin to 25.5 inches outboard in accordance with 707, 720 NDT Manual Part 6, 55-10-07, Figure 1. (2) Inspect for cracks in the space between the inspar skin and the forward edge of the exposed upper surface of the chord. Inspect from the side of the body outboard to Stabilizer Station 92.55 in accordance with 707, 720 NDT Manual Part 6, 55-10-07, Figure 2. (3) Inspect for cracks in the space between the trailing edge skin and the aft edge of the exposed upper surface of the chord. Inspect from the side of the body outboard to Stabilizer Station 92.55 in accordance with 707, 720 NDT Manual Part 6, 55-10-07, Figure 2. (4) Inspect for cracks in the aft flange of the chord along the fasteners common to the skin. Inspect from the inboard edge of the trailing edge skin to 25.5 inches outboard in accordance with 707, 720 NDT Manual Part 6, 55-10-07, Figure 3. (5) Inspect for cracks along the forward and aft edges of the exposed upper surface of the chord. Inspect from the side of the body outboard to Stabilizer Station 92.55 in accordance with 707, 720 NDT Manual Part 6, 55-10-07, Figure 7. b. If a crack is found: (1) Contact Boeing for repair instructions or (2) Replace the spar chord as given in Accomplishment Instructions Paragraph 3.B.6. Part 6. c. Apply corrosion inhibiting compound BMS 3-23 or equivalent to the exposed area of the chord. Refer to SOPM 20-41-05 as an accepted procedure. d. Put the airplane back to a serviceable condition. 4. Part 4 - Chord Inspection - Horizontal Stabilizer - Rear Spar - Upper and Lower Chord - Web Flange - Stabilizer Station 92.55 to 272.55

Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: December 19, 2007 A3515 Revision 1: October 10, 2014 27 of 38 **BOEING SERVICE BULLETIN A3515 ALERT**  **ALERT Upper and Lower Chords, Horizontal Stabilizer Rear Spar, Made From 7079**  a. Remove and keep the elevator balance bay number 2 through number 5 panels. Refer to 707 AMM 27-07-31 as an accepted procedure. b. Remove and keep the cove shells and supporting structures as required to get access to the aft surface of the vertical flanges of the upper and lower chords. c. Do a High Frequency Eddy Current (HFEC) inspection of the web flanges of the upper and lower chords between stabilizer station 92.55 and 272.55 for cracks as given in FIGURE 1. d. If a crack is found: (1) Replace the spar chord as given in Accomplishment Instructions Paragraph 3.B.6. Part 6 or (2) Complete steps (a) and (b) that follow: (a) Determine if the crack meets the limits defined in Boeing Service Bulletin 707-3356 and has been repaired according to Boeing Service Bulletin 707-3356. 1) For each crack that meets the limits of Boeing Service Bulletin 707-3356, Part III - Repair, Notes (a) and (b), contact Boeing for new repair instructions. 2) For each crack that has been repaired according to Boeing Service Bulletin 707-3356, Part III - Repair Paragraph C, determine if the crack still meets the limits of Boeing Service Bulletin 707-3356, Part III - Repair Paragraph C, and determine if the crack meets the following supplemental limits: a) The crack path must be within the limits as given in FIGURE 1, View B-B. b) The crack must terminate in an existing fastener hole. c) There must be two or more fastener locations in the repair area as given in FIGURE 1, View B-B that have no cracks indicated in the adjacent spaces. d) A stiffener bay with a crack in the upper chord must not also have a crack in the upper or lower chord of either of the adjacent stiffener bays. e) A stiffener bay with a crack in the lower chord must not also have a crack in the upper or lower chord of either of the adjacent stiffener bays. 3) For a crack that meets the limits of Boeing Service Bulletin 707-3356, Part III - Repair Paragraph C, but is not repaired as given in Boeing Service Bulletin 707-3356, Part III - Repair Paragraph C, accomplish the repair as given in Boeing Service Bulletin 707-3356, Part III - Repair Paragraph C. Obey the supplemental limits that follow: a) The crack path must be within the limits as given in FIGURE 1, View B-B. b) The crack must terminate in an existing fastener hole.

Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: December 19, 2007 A3515 Revision 1: October 10, 2014 28 of 38 **BOEING SERVICE BULLETIN A3515 ALERT**  **ALERT**c) There must be two or more fastener locations in the repair area as given in FIGURE 1, View B-B that have no crack indicated in the adjacent spaces. d) A stiffener bay with a crack in the upper chord must have no crack in the upper or lower chord of either of the adjacent stiffener bays. e) A stiffener bay with a crack in the lower chord must have no crack in the upper or lower chord of either of the adjacent stiffener bays. 4) For a crack that meets the limits of Boeing Service Bulletin 707-3356, Part III - Repair Paragraph D, accomplish the repair according to Boeing Service Bulletin 707-3356, Part III - Repair Paragraph D, unless already accomplished. 5) For a crack that does not meet the limits defined in the preceding paragraphs 1., 2., 3., & 4. above, contact Boeing for new repair instructions. (b) Determine if all 7079 upper and lower chord segments installed on the horizontal stabilizer have had Boeing Service Bulletin 707-3356 Part II, Group 1 Preventative Modification done. If not yet accomplished, do the Boeing Service Bulletin 707-3356 Part II, Group 1 Preventative Modification on all 7079 chord segments still installed on the horizontal stabilizer. **NOTE:** Boeing Service Bulletin 707-3356 Part II, Group 1 Preventative Modification is applicable to airplanes for which all chord segments (upper and lower inboard, upper and lower outboard) are made from 7079. It is therefore inclusive of all configurations where 7079 chord segments remain. Since 7079 chords may have been replaced with 7075 chords, it is only necessary to do the modification where the 7079 chord segments are identified. e. Apply corrosion inhibiting compound BMS 3-23 or equivalent to the exposed area of the horizontal stabilizer rear spar chords. Refer to SOPM 20-41-05 as an accepted procedure. f. Restore the airplane to a serviceable condition. 5. Part 5 - Chord Inspection - Horizontal Stabilizer - Rear Spar - Upper and Lower Chord - Forward Skin Flange - Stabilizer Station -13.179 to 272.55 **Upper and Lower Chords of the Horizontal Stabilizer Rear Spar Made From 7079** a. Remove and keep the elevator balance bay number 0 through number 5 panels. Refer to 707 AMM 27-07-31 as an accepted procedure. b. Do a Low Frequency Eddy Current (LFEC) inspection of the forward skin flange of the upper chord between stabilizer station 182.55 and 272.55 for cracks as given in FIGURE 2. c. Do a LFEC inspection of the forward skin flange of the upper chord between stabilizer station 92.55 and 182.55 for cracks as given in FIGURE 3. d. Do a LFEC inspection of the forward skin flange of the lower chord between stabilizer station 182.55 and 272.55 for cracks as given in FIGURE 4. e. Do a LFEC inspection of the forward skin flange of the lower chord between stabilizer station 92.55 and 182.55 for cracks as given in FIGURE 5.

Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: December 19, 2007 A3515 Revision 1: October 10, 2014 29 of 38 **BOEING SERVICE BULLETIN A3515 ALERT**  **ALERT**f. Do a LFEC inspection of the forward skin flange of the lower chord between stabilizer station -13.179 and 92.55 for cracks as given in FIGURE 6. g. If a crack is found: (1) Replace the lower chord as given in Accomplishment Instructions Paragraph 3.B.6. Part 6 or (2) Complete steps (a) and (b) that follow: (a) Contact Boeing for repair instructions. (b) Determine if all 7079 upper and lower chord segments installed on the horizontal stabilizer have had Service Bulletin 707-3381 Part II - Preventative Modification accomplished. If not yet accomplished, do the Service Bulletin 707-3381 Part II - Preventative Modification on all 7079 chord segments still installed on the horizontal stabilizer. **NOTE:** Service Bulletin 707-3381 Part II - Preventative Modification is applicable to airplanes for which all chord segments (upper and lower inboard, upper and lower outboard) are made from 7079. It is therefore inclusive of all configurations where 7079 chord segments remain. Since 7079 chords may have been replaced with 7075 chords, it is only necessary to do the modification where the 7079 chord segments are identified. h. Apply corrosion inhibiting compound BMS 3-23 or equivalent to exposed area of the upper and lower chords. Refer to SOPM 20-41-05 as an accepted procedure. i. Restore the airplane to a serviceable condition. 6. Part 6 - Chord Replacement a. Replace the applicable rear spar chord segment or segments according to standard procedures and instructions supplied with the applicable parts kits and tooling. Reference assembly drawing 65-3321, 65-3322 and 65-3323 for the rear spar upper, lower and center inboard chords respectively. b. Upon completion of chord replacement, revise the data on the APPENDIX A data sheet to match the chord configuration currently on the airplane. c. Retain the updated APPENDIX A data sheet with the airplane records

Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: December 19, 2007 A3515 Revision 1: October 10, 2014 30 of 38 **BOEING SERVICE BULLETIN A3515 ALERT**  **ALERT FIGURE 1: HORIZONTAL STABILIZER - REAR SPAR - UPPER AND LOWER - INBOARD AND OUTBOARD**  **- CHORD WEB FLANGE - STABILIZER STATION 92.55 TO STABILIZER STATION 272.55 - INSPECTION (SHEET 1 OF 2)** 
Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: December 19, 2007 A3515 Revision 1 October 10, 2014 31 of 38 **BOEING SERVICE BULLETIN A3515 ALERT**  **ALERT**The step numbers shown below agree with the numbers shown in the circle symbols in the figure.
**MORE DATA QTY**  **IDENTIFICATION NAME**  **TASK STEP** 

- - Number 2, 3, 4 and 5 Balance Bay Access 1 See Table 1.(a) 2

- Chord Web Flange Inspect 2 (a) Do a High Frequency Eddy Current (HFEC) inspection of the left and right side horizontal stabilizer rear spar upper and lower inboard and outboard chord web flange between stabilizer station 92.55 and 272.55 for any cracking. Use a pencil probe to scan the aft surface of the chord vertical flange between fasteners and along the tangent line of the flange fillet in accordance with 707, 720 NDT, Part 6, 51-00-00, Figure 4.
**Table 1 Balance Bay to Inspect**  **7079 Chord Segment** 2,3 Upper Inboard 2,3 Lower Inboard 4,5 Upper Outboard 4,5 Lower Outboard

**FIGURE 1: HORIZONTAL STABILIZER - REAR SPAR - UPPER AND LOWER - INBOARD AND OUTBOARD - CHORD WEB FLANGE - STABILIZER STATION 92.55 TO STABILIZER STATION 272.55 - INSPECTION**  **(SHEET 2 OF 2)**
Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: December 19, 2007 A3515 Revision 1 October 10, 2014 32 of 38 **BOEING SERVICE BULLETIN A3515 ALERT**  **ALERT**The step numbers shown below agree with the numbers shown in the circle symbols in the figure.
**MORE DATA QTY**  **IDENTIFICATION NAME**  **TASK STEP**  (a) 2

- Forward Skin Flange Inspect 1 (a) Do a Low Frequency Eddy Current (LFEC) inspection of the left and right side horizontal stabilizer rear spar upper outboard chord forward skin flange between stabilizer station 182.55 and 272.55 for any cracking in accordance with 707, 720 NDT, Part 6, 55-10-07, Figure 8.

**FIGURE 2: HORIZONTAL STABILIZER - REAR SPAR - UPPER OUTBOARD CHORD - FORWARD SKIN FLANGE - STABILIZER STATION 182.55 TO STABILIZER STATION 272.55 - INSPECTION**  **(SHEET 1 OF 1)**
Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: December 19, 2007 A3515 Revision 1 October 10, 2014 33 of 38 **BOEING SERVICE BULLETIN A3515 ALERT**  **ALERT**The step numbers shown below agree with the numbers shown in the circle symbols in the figure.
**MORE DATA QTY**  **IDENTIFICATION NAME**  **TASK STEP**  (a) 2

- Forward Skin Flange Inspect 1 (a) Do a Low Frequency Eddy Current (LFEC) inspection of the left and right side horizontal stabilizer rear spar upper inboard chord forward skin flange between stabilizer station 92.55 and 182.55 for any cracking in accordance with 707, 720 NDT, Part 6, 55-10-07, Figure 8.

**FIGURE 3: HORIZONTAL STABILIZER - REAR SPAR - UPPER INBOARD CHORD - FORWARD SKIN FLANGE - STABILIZER STATION 92.55 TO STABILIZER STATION 182.55 - INSPECTION**  **(SHEET 1 OF 1)**
Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: December 19, 2007 A3515 Revision 1 October 10, 2014 34 of 38 **BOEING SERVICE BULLETIN A3515 ALERT**  **ALERT**The step numbers shown below agree with the numbers shown in the circle symbols in the figure.
**MORE DATA QTY**  **IDENTIFICATION NAME**  **TASK STEP**  (a) 2

- Forward Skin Flange Inspect 1 (a) Do a Low Frequency Eddy Current (LFEC) inspection of the left and right side horizontal stabilizer rear spar lower outboard chord forward skin flange between stabilizer station 182.55 and 272.55 for any cracking in accordance with 707, 720 NDT, Part 6, 55-10-07, Figure 8.

**FIGURE 4: HORIZONTAL STABILIZER - REAR SPAR - LOWER OUTBOARD CHORD - FORWARD SKIN FLANGE - STABILIZER STATION 182.55 TO STABILIZER STATION 272.55 - INSPECTION**  **(SHEET 1 OF 1)**
Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: December 19, 2007 A3515 Revision 1 October 10, 2014 35 of 38 **BOEING SERVICE BULLETIN A3515 ALERT**  **ALERT**The step numbers shown below agree with the numbers shown in the circle symbols in the figure.
**MORE DATA QTY**  **IDENTIFICATION NAME**  **TASK STEP**  (a) (b) 2

- Forward Skin Flange Inspect 1 (a) Do a Low Frequency Eddy Current (LFEC) inspection of the left and right side horizontal stabilizer rear spar lower inboard chord forward skin flange between stabilizer station 92.55 and 182.55 for any cracking in accordance with 707, 720 NDT, Part 6, 55-10-07, Figure 8. (b) Exclude inspection of areas not accessible due to interference with any vortex generators mounted on the lower surface. However, if any cracks are found at any of the first six (6) inspectable fasteners on either side of the vortex generator, remove the vortex generator and inspect all fastener locations.

**FIGURE 5: HORIZONTAL STABILIZER - REAR SPAR - LOWER INBOARD CHORD - FORWARD SKIN FLANGE - STABILIZER STATION 92.55 TO STABILIZER STATION 182.55 - INSPECTION**  **(SHEET 1 OF 1)**
Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: December 19, 2007 A3515 Revision 1 October 10, 2014 36 of 38 **BOEING SERVICE BULLETIN A3515 ALERT**  **ALERT**The step numbers shown below agree with the numbers shown in the circle symbols in the figure.
**MORE DATA QTY**  **IDENTIFICATION NAME**  **TASK STEP**  (a) (b) 2

- Forward Skin Flange Inspect 1 (a) Do a Low Frequency Eddy Current (LFEC) inspection of the left and right side horizontal stabilizer rear spar lower inboard chord forward skin flange between stabilizer station -13.179 and 92.55 for any cracking in accordance with 707, 720 NDT, Part 6, 55-10-07, Figure 8. (b) Exclude inspection of areas not accessible due to interference with any vortex generators mounted on the lower surface. However, if any cracks are found at any of the first six (6) inspectable fasteners on either side of the vortex generator, remove the vortex generator and inspect all fastener locations.

**FIGURE 6: HORIZONTAL STABILIZER - REAR SPAR - LOWER INBOARD CHORD - FORWARD SKIN FLANGE - STABILIZER STATION -13.179 TO STABILIZER STATION 92.55 - INSPECTION**  **(SHEET 1 OF 1)**
Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: December 19, 2007 A3515 Revision 1 October 10, 2014 37 of 38 **BOEING SERVICE BULLETIN A3515 ALERT**  **ALERT FLIGHT CYCLES:**  **FLIGHT HOURS: AIRPLANE REGISTRY:**  LEFT SIDE Horizontal Stabilizer Stabilizer Serial Number (a): Stabilizer Part Number (a): Spar Chord Material (b): (from Part 2 - Configuration Check) Location Spar Chord Seg- ment Side of Body to SSTA 182.55 Upper Inboard Side of Body to SSTA 182.55 Lower Inboard SSTA 182.55 to Stabilizer Tip Upper Outboard SSTA 182.55 to Stabilizer Tip Lower Outboard RIGHT SIDE Horizontal Stabilizer Stabilizer Serial Number (a): Stabilizer Part Number (a): Spar Chord Material (b) (from Part 2 - Configuration Check) Location Spar Chord Seg- ment Side of Body to SSTA 182.55 Upper Inboard Side of Body to SSTA 182.55 Lower Inboard SSTA 182.55 to Stabilizer Tip Upper Outboard SSTA 182.55 to Stabilizer Tip Lower Outboard
Record the horizontal stabilizer part number and serial number as recorded on the data plate. (a) Record spar chord material, 7079-T6 or 7075-T73511, as determined from maintenance record review, or electrical conductivity test. Do the electrical conductivity test in accordance with 707 Non-Destructive Testing (NDT) Manual D6-48023 Part 6, 51-00-00, Figure 20, dated April 5, 2004, and Boeing Process Specification BAC5946, Table I, Page 12, Revision (AA) dated July 9, 2001. (b)

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**Appendix A: CONFIGURATION VERIFICATION - INSPECTION RESULTS FORM - MATERIAL DATA (SHEET 1 OF 1)** 
Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: December 19, 2007 A3515 Revision 1 October 10, 2014 38 of 38 **BOEING SERVICE BULLETIN A3515 ALERT**  **ALERT**