December 19, 2007

A3515

BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. 1 of 41

ALERT ALERT

Commercial

Airplane

Group 707

ALERT ALERT

Service Bulletin

Number: A3515

Date: December 19, 2007

ATA System: 5510

SUBJECT: STABILIZERS - Horizontal Stabilizer - Rear Spar Upper and Lower Chords - Inspection 

and Repair

BOEING PROPRIETARY, CONFIDENTIAL, AND/OR TRADE SECRET

Copyright © 2007 The Boeing Company

Unpublished Work - All Rights Reserved

Boeing claims copyright in each page of this document only to the extent that the page contains copyrightable 

subject matter. Boeing also claims copyright in this document as a compilation and/or collective work.

This document includes proprietary information owned by The Boeing Company and/or one or more third 

parties. Treatment of the document and the information it contains is governed by contract with Boeing. For 

more information, contact The Boeing Company, P.O. Box 3707, Seattle, Washington 98124.

Boeing, the Boeing signature, the Boeing symbol, 707, 717, 727, 737, 747, 757, 767, 777, BBJ, DC-8, DC-9, 

DC-10, MD-10, MD-11, MD-80, MD-88, MD-90, and the red-white-and-blue Boeing livery are all trademarks 

owned by The Boeing Company; and no trademark license is granted in connection with this document unless 

provided in writing by Boeing.
 BLANK PAGE

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BOEING SERVICE BULLETIN A3515

ALERT ALERT

BLANK PAGE
 Table of Contents

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BOEING SERVICE BULLETIN A3515

ALERT ALERT

Table of Contents

Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5

1. PLANNING INFORMATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9

A. Effectivity . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9

1. Airplanes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9

2. Spares Affected . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16

B. Concurrent Requirements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16

C. Reason . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16

D. Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17

E. Compliance. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17

F. Approval . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21

G. Manpower . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21

H. Weight and Balance Changes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22

I. Electrical Load Data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22

J. References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22

1. Existing Data: . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22

2. Data supplied with this Service Bulletin: . . . . . . . . . . . . . . . . . . . . . . . . . 22

3. Installation Drawings Used in the Preparation of this Service Bulletin: . . . . . . . . . . 22

K. Publications Affected . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23

L. Interchangeability and Intermixability of Parts . . . . . . . . . . . . . . . . . . . . . . . . . 23

2. MATERIAL INFORMATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25

A. Material - Price and Availability. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25

B. Industry Support Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25

C. Parts Necessary For Each Airplane . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25

1. Kits/Parts: . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25

2. Parts and Materials Supplied by the Operator: . . . . . . . . . . . . . . . . . . . . . . 25

3. Parts Modified and Reidentified: . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25

4. Parts Removed and Not Replaced: . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26

D. Parts Necessary to Change Spares . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26

E. Special Tooling - Price and Availability. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26

F. Special Tooling Necessary to do this Service Bulletin . . . . . . . . . . . . . . . . . . . . . 26

3. ACCOMPLISHMENT INSTRUCTIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27

A. GENERAL INFORMATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27

B. WORK INSTRUCTIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27

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 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34

FIGURE 2: HORIZONTAL STABILIZER - REAR SPAR - UPPER OUTBOARD CHORD - FORWARD SKIN

FLANGE - STABILIZER STATION 182.55 TO STABILIZER STATION 272.55 -

INSPECTION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36

FIGURE 3: HORIZONTAL STABILIZER - REAR SPAR - UPPER INBOARD CHORD - FORWARD SKIN

FLANGE - STABILIZER STATION 92.55 TO STABILIZER STATION 182.55 - INSPECTION

37

FIGURE 4: HORIZONTAL STABILIZER - REAR SPAR - LOWER OUTBOARD CHORD - FORWARD SKIN

FLANGE - STABILIZER STATION 182.55 TO STABILIZER STATION 272.55 -

INSPECTION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 38

FIGURE 5: HORIZONTAL STABILIZER - REAR SPAR - LOWER INBOARD CHORD - FORWARD SKIN
 Table of Contents

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BOEING SERVICE BULLETIN A3515

ALERT ALERT

FLANGE - STABILIZER STATION 92.55 TO STABILIZER STATION 182.55 - INSPECTION

39

FIGURE 6: HORIZONTAL STABILIZER - REAR SPAR - LOWER INBOARD CHORD - FORWARD SKIN

FLANGE - STABILIZER STATION -13.179 TO STABILIZER STATION 92.55 - INSPECTION

40

APPENDIX A: CONFIGURATION VERIFICATION - INSPECTION RESULTS FORM - MATERIAL DATA

41
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ALERT ALERT

Commercial

Airplane

Group 707

ALERT ALERT

Service Bulletin

Number: A3515 Summary

Date: December 19, 2007

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 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. 

Service Bulletin 707A3515 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.

The actions of this service bulletin addressing Issue 1 are necessary to adequately detect development of 

stress corrosion cracking.

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 bulletin 707A3313 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.
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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.

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

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.
 

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BOEING SERVICE BULLETIN A3515

ALERT ALERT

REPAIR AS NECESSARY

INSPECT CHORDS

DEFINE CHORD MATERIAL

CHORD

A

A 182.55

STAB STA

STAB STA

92.55

272.55

STAB STA

FRONT SPAR

LEFT HORIZONTAL STABILIZER SHOWN, 

RIGHT OPPOSITE

A-A

ELEVATOR

REAR SPAR

HINGE

496408
 

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BOEING SERVICE BULLETIN A3515

ALERT ALERT

BLANK PAGE
December 19, 2007

A3515

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ALERT ALERT

Commercial

Airplane

Group 707

ALERT ALERT

Service Bulletin

Number: A3515

Date: December 19, 2007

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.

Airplane models:

707-300 707-300B 707-300C 707-400

IDENTIFICATION BY CUSTOMER, CUSTOMER CODE, GROUP AND NUMBER

ADC AIRLINES (ADN)

1 07816

GROUP CONFIGURATION DESCRIPTION

1 - All horizontal stabilizer rear spar chords made 

from 7079-T6.

2 - Horizontal stabilizer rear spar upper inboard and 

upper outboard chords made of 7079-T6.

3 - Left side horizontal stabilizer rear spar upper 

inboard chords made from 7079-T6.

4 - All horizontal stabilizer rear spar chords made 

from 7075-T73511.
 

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BOEING SERVICE BULLETIN A3515

ALERT ALERT

AERO SANTAMARIA (SMK)

1 08475

AEROSPACE CONSORTIUM (CTU)

1 08223

AFRICAN AIRLINES (AFX)

1 05632

AIR ATLANTIC NIGERIA (NGE)

1 07042 08472

AIR GULF FALCON (GFG)

1 05961 08077

AIR MEMPHIS (MEP)

1 08405

AIR NACOIA (NAO)

1 07071

ALG TRANSPORTATION, INC. (ALW)

1 07052 07458

ARGENTINE AIR FORCE (AGF)

1 05854 08310 08452

4 06461

ASNET (SRC)

1 08127

AVIATION CONSULTANTS (ACT)

1 05965 07602–07603

AVIATION RESEARCH CENTRE (AVR)

1 07701–07702

BETA (BRQ)

1 07261 07270 07625 08072

BIN MAHFOOZ AVIATION (BMV)

1 08404

CARGO PLUS AVIATION (CPB)

1 08191

CHILEAN AIR FORCE (CHF)

1 05305 07619 07661

COLOMBIAN AIR FORCE (CLB)

1 07109 08582
 

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BOEING SERVICE BULLETIN A3515

ALERT ALERT

CRYSTAL TRADING (CTR)

1 07907

DAIRO AIR SERVICES (DAR)

1 07616 07802

DOLPHIN AIR (FDN)

1 09001

EURO OCEANIC AIR TRANSPORT (EOA)

1 08309

EXPORT RESTRICTED AIRPLANES (YWV)

1 05019 07016 08054 08101

08551–08553 09101–09102

2 09231

3 09103–09105 09232

4 09106–09107 09161–09167 09438

FEDERATIVE REPUBLIC OF BRAZIL (BRZ)

1 07080 08304 08308 08314

FIRST INTERNATIONAL AIRWAYS (FIW)

1 07207 09201

2 09203

G.M.A.S. (GMA)

1 07049

GE (GEC)

1 02017

GOVERNMENT OF ANGOLA (AGL)

1 05035 05051 06402

HEWA BORA AIRWAYS (EXD)

1 08206

INTER AIR (ITI)

1 07253

INTERNATIONAL AIR LEASES (IAL)

1 05125 07043 07606 07618

IRAQI AIRWAYS (IRQ)

3 09221–09223

ISRAELI AIR FORCE (ISR)

1 02105 02114–02115 02203 02206–02207

05208 06403 07406–07407 08021

08243 08251 09004

4 09251 09421 09441
 

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BOEING SERVICE BULLETIN A3515

ALERT ALERT

ITALIAN AIR FORCE (ITC)

1 05823 05827 08329–08330

KODA AIR (KGO)

1 07105

L-3 COMMUNICATIONS (LCS)

1 08172

LIBYAN AIRWAYS (LAA)

1 05037 07046 07502–07503 07819

4 09411

LOWA, LTD. (LOW)

1 05307

MIAMI AVIATION SERVICE (MIA)

4 06451

MIT LINCOLN LABORATORIES (MIT)

1 05009

NATO (NAT)

1 07905–07906 08221 08224

NORTHROP GRUMMAN CORPORATION (GRU)

1 07812 07817 09002

OMEGA AIR (OMG)

1 05966 07623

OMEGA AIR, INC. (OMH)

1 05055 05603 05968 08055

3 08209

4 09227 09290

PAKISTAN INT'L AIRLINES (PIA)

1 05633 07267 08144 08325

PARAGUAYAN AIR FORCE (FAP)

1 05018

PERUVIAN AIR FORCE (PRF)

1 07266

REPUBLIC DEMOCRATIC OF CONGO (ZAR)

1 05824 08129

ROMAVIA (ROA)

1 09202
 

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BOEING SERVICE BULLETIN A3515

ALERT ALERT

ROYAL AUSTRALIAN AIR FORCE (RAA)

1 07814–07815 07818 07820

4 09288

ROYAL JORDANIAN (RJA)

1 07078 08173 09003 09006

SKY AIR CARGO (SAC)

1 07201

SKY AVIATION (SYV)

1 05048

SKYMASTER AIRLINES (SKA)

1 07058 07077 07622 07801

08471

SOUTH AFRICAN AIRFORCE (SFF)

1 08004–08005 08008 08242 08244

SPANISH AIR FORCE (SAF)

1 05131 07405 07611

4 09289

TRANS MEDITERRANEAN AIRWAYS (TMA)

1 07041 07206 07453 08121–08122

TRISTAR (TYS)

1 08203

US AIR FORCE (USF)

1 05826 07057 07107 07212–07213

07254 07256 07258 07807–07810

07813 08222 08271 08313

08327 08407–08410

VENEZUELAN AIR FORCE (VEN)

1 08103–08104

WIMBI DIRA (WIM)

1 07262

WORLD AIRWAYS (GMR)

1 07075

IDENTIFICATION BY NUMBER

Variable Group

02001–02020 1

02101–02121 1

02201–02207 1
 

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BOEING SERVICE BULLETIN A3515

ALERT ALERT

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 1

06451 4

06461 4

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

Variable Group
 

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BOEING SERVICE BULLETIN A3515

ALERT ALERT

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 1

08209–08210 3

08221–08224 1

08241–08244 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 1

09103–09105 3

09106–09107 4

Variable Group
 

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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 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. Service Bulletin 707A3515 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.

The actions of this service bulletin addressing Issue 1 are necessary to adequately detect 

development of stress corrosion cracking.

2. ISSUE 2 - Early Fatigue Cracking in the Inboard Segment of the Upper Chord in the Horizontal 

Stabilizer Rear Spar

09161–09167 4

09201–09202 1

09203 2

09204 4

09221–09223 3

09227 4

09231 2

09232 3

09251 4

09271 4

09281 4

09286–09290 4

09411 4

09421 4

09438 4

09441 4

Variable Group
 

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BOEING SERVICE BULLETIN A3515

ALERT ALERT

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 bulletin 707A3313 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.

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.

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.
 

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BOEING SERVICE BULLETIN A3515

ALERT ALERT

Boeing recommends the following:

Table 1: Determine Flight Cycles and Material of Horizontal Stabilizer Structural Components

Condition Action Compliance Time

Repeat Interval 

(Not to Exceed)

All airplanes Determine flight cycles as given 

in Accomplishment Instructions 

paragraph 3.B.1. Part 1.

At time of service bulletin release -

All airplanes Determine material of the left 

and right side horizontal 

stabilizer structural components 

as given in Accomplishment 

Instructions Paragraph 3.B.2. 

Part 2.

Within 180 calendar days after 

the date of this service bulletin

 or

before further flight when the 

horizontal stabilizer is replaced

180 calender 

days or 250 total 

flight cycles, 

whichever 

occurs first (a)

Airplanes with 

horizontal stabilizer 

components made 

from 7075 as found 

in the 

Accomplishment 

Instructions 

Paragraph 3.B.2 

Part 2

Inspect and repair the horizontal 

stabilizer structural components 

as given in Table 2. (b)

- -

Airplanes with 

horizontal stabilizer 

components made 

from 7079 as found 

in the 

Accomplishment 

Instructions 

Paragraph 3.B.2 

Part 2 

Inspect and repair the horizontal 

stabilizer structural components 

as given in Table 3. (b)

- -

(a) See Part 1 - Cycle Counting Procedure for definition of “cycles.”

(b) If you have a mixture of 7075 components and 7079 components, use Tables 2 and 3.
 

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Table 2: Inspect and Repair Horizontal Stabilizer Structural Components Made From 7075 Material

Condition Action Compliance Time

Repeat Interval 

(Not to Exceed)

Airplanes with 

horizontal stabilizer 

components made 

from 7075

Inspect and repair the upper 

chord on the inboard end of 

the rear spar in the left and 

right side horizontal stabilizers 

from stabilizer station -13.179 

to 92.55 as given in 

Accomplishment Instructions 

Paragraph 3.B.3. Part 3.

Within 180 calendar days or 500 

flight cycles after the date of this 

service bulletin, whichever 

occurs first (a) (c)

 or

before further flight when the 

horizontal stabilizer is being 

replaced (c)

500 total flight 

cycles (a)

The chord is 

replaced as given in 

Accomplishment 

Instructions 

Paragraph 3.B.6 

Part 6

Inspect and repair the upper 

chord on the inboard end of 

the rear spar that was 

replaced from stabilizer 

station -13.179 to 92.55 as 

given in Accomplishment 

Instructions Paragraph 3.B.3. 

Part 3. (b)

Within 4000 total flight cycles 

after the date of chord 

replacement (a)

500 total flight 

cycles (a)

(a) See Part 1 - Cycle Counting Procedure for definition of “cycles.”

(b) Continued inspections are only necessary for upper chords of the inboard end of the rear spar that are 

made from 7075. Continued inspections are not necessary for other spar chord components replaced with 

7075 parts.

(c) When you replace the chord as given in Accomplishment Instructions Paragraph 3.B.6 Part 6, you can 

defer the chord inspection given in Accomplishment Instructions Paragraph 3.B.3. Part 3 for a maximum of 

4,000 total flight cycles.
 

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Table 3: Inspect and Repair Horizontal Stabilizer Structural Components Made From 7079 Material

Condition Action

Compliance Time Repeat Interval 

(Not to Exceed)

Airplanes with 

horizontal stabilizers 

that have rear spar 

chord compenents 

made from 7079

Inspect and repair the upper 

chord of the inboard side of the 

rear spar in the left and right 

side horizontal stabilizers from 

stabilizer station -13.179 to 

92.55 as given in 

Accomplishment Instructions 

Paragraph 3.B.3. Part 3.

Within 180 calendar days or 250 

flight cycles after the date of this 

service bulletin, whichever occurs 

first (a)

 or

before further flight when the 

horizontal stabilizer is being 

replaced

180 calender days 

or 250 total flight 

cycles, whichever 

occurs first (a)

Inspect and repair the web 

flanges of the upper and lower 

chords of the rear spar in the 

left and right side horizontal 

stabilizers from stabilizer 

station 92.55 to 272.55 as 

given in Accomplishment 

Instructions Paragraph 3.B.4. 

Part 4. (b)

Within 180 calendar days or 1000 

flight cycles after the date of this 

service bulletin, whichever occurs 

first (a)

 or

before further flight when the 

horizontal stabilizer is being 

replaced

180 calender days 

or 1000 total flight 

cycles, whichever 

occurs first (a)

Inspect and repair the forward 

skin flanges of the upper and 

lower chords of the rear spar in 

the left and right side 

horizontal stabilizers from 

stabilizer station -13.179 to 

272.55 as given in 

Accomplishment Instructions 

Paragraph 3.B.5. Part 5. (b)

Airplanes with 

horizontal stabilizers 

that have rear spar 

chord components 

made from 7079 for 

which the Service 

Bulletin 707-3381 

Part II - Preventative 

Modificaiton is not 

completed

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

or

replace the chord as given in 

Accomplishment Instructions 

Paragraph 3.B.6 Part 6.

Before further flight -

(a) See Part 1 - Cycle Counting Procedure for definition of “cycles.”

(b) Only those components 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. Components 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.
 

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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, Revision 1. The inspections contained in this service bulletin have 

been reviewed and approved as an alternate method of compliance to the requirements of Paragraph 

(A) of AD 85-12-01 for SSID item 55-A25-03, 55-A35-03 and 55-A45-03 covered by this service 

bulletin. All other provisions of AD 85-12-01 that are not specifically referenced above remain fully 

applicable and must be complied with.

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.

Task

Number of 

Persons Task Hours Elapsed Hours

Open Access 2 1.0 0.5

Part 1 - (a) (a)

Part 2 2 1.0(b) 0.5(b)

Part 3 4 26.0 6.5

Part 4 4 32.0 8.0

Part 5 4 24.0 6.0

Part 6 (c) (c) (c)

Close Access 2 1.0 0.5

TOTAL FOR EACH AIRPLANE (d) (d)

(a) Considered Lost Time. Not able to estimate.
 

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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. 707 Aircraft Maintenance Manual (AMM) 27-07-31.

c. 707 Nondestructive Test (NDT) Manual D6-48023, Part 6, Subject 51-00-00, Figure 20.

d. 707 Nondestructive Test (NDT) Manual D6-48023, Part 6, Subject 55-10-07, Figure 1, 

Figure 3 and Figure 7.

e. 707 Supplemental Structural Inspection Document (SSID) D6-44860, Revision P, Item 55-

A25-03, 55-A35-03 and 55-A45-03.

f. 707, 720 Nondestructive Testing (NDT) Manual, Part 6, 51-00-00, Figure 20, Part 6, 

55-10-07 Figure 1, Figure 3 and Figure 7.

g. Boeing Service Bulletin 707-3356 - “STABILIZERS - HORIZONTAL STABILIZER REAR 

SPAR CHORD INSPECTION, MODIFICATION AND REPAIR”. 

h. Boeing Service Bulletin 707-3381 -”EMPENNAGE - HORIZONTAL STABILIZER REAR 

SPAR CHORD FORWARD FLANGE INSPECTION”.

i. Service Related Problem (SRP) 707-SRP-55-0033.

j. Standard Overhaul Practices Manual (SOPM) 20-41-05.

2. Data supplied with this Service Bulletin:

None.

3. Installation Drawings Used in the Preparation of this Service Bulletin:

None.

(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.

Task

Number of 

Persons Task Hours Elapsed Hours
 

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K. Publications Affected

None.

L. Interchangeability and Intermixability of Parts

Accomplishment of this service bulletin does not affect interchangeability or intermixability of parts.
 

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BLANK PAGE
 

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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:

3. Parts Modified and Reidentified:

None.

Part Number / 

Specification QTY Name Notes

65-95600-887 1 Upper Chord, Inboard, Left Side (a) (c) (d)

65-95600-888 1 Upper Chord, Inboard, Right Side (a) (c) (e)

65-95600-701 1 Lower Chord, Inboard, Left Side (a) (c) (f)

65-95600-702 1 Lower Chord, Inboard, Right Side (a) (c) (g)

65C80665-165 1 Upper Chord, Outboard, Left Side (a) (c) (h)

65C380665-165 1 Lower Chord, Outboard, Right Side (a) (c) (h)

65C380665-166 1 Lower Chord, Outboard, Left Side (a) (c) (I)

65C80665-166 1 Upper Chord, Outboard, Right Side (a) (c) (i)

BMS 3-23 Type II 1 Pint Corrosion Inhibiting compound (b)

(a) Discard the existing part.

(b) See the Qualified Products List at the end of the Boeing Material Specification (BMS) for supplier data.

(c) You can use the existing part to replace the new or changed part. If you use the existing part, you cancel 

the effect of the change given in this service bulletin. The existing part is interchangeable and 

intermixable with the new part.

(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.
 

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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 NDT Manual D6-48023 Part 1, Section 51-01-00.
 

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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. A Special Detailed Inspection is defined as: An intensive 

examination of a specific item, installation, or assembly to detect 

damage, failure, or irregularity. The examination is likely to make 

extensive use of specialized Inspection techniques and/or 

equipment. Intricate cleaning and substantial access or disassembly 

procedure may be required.

4. These work instructions refer to procedures included on 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 “as given in” are 

included in the instruction, the procedure in the Boeing document 

must be used.

5. Refer to Appendix A for configuration verification, inspection, 

material data results form.

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
 

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a. Determine what material the left and right side horizontal stabilizer, rear 

spar, upper chords and lower chords on the inboard and outboard ends 

of the rear spar are made of using one of the following methods:

(1) Review the airplane's 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).

(2) Do a conductivity test to determine whether each upper chord and 

lower chord on the horizontal stabilizer rear spar listed in Appendix 

A is made from 7079-T6 or 7075-T73511 material. Refer to 707, 

720 NDT, Part 6, 51-00-00, Figure 20 dated April 5, 2004 as an 

accepted procedure.

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 92.55e

Upper Chords, Horizontal Stabilizer Rear Spar, Inboard Side, Made From 

7075 and 7079

a. Do a special detailed inspection of the upper chord on the inboard side 

of the rear spar of the left and right side horizontal stabilizer as follows:

(1) Inspect for cracks in the forward flange of the upper chord of the 

rear spar along the fasteners common to the skin and the upper 

chord. Inspect from the inboard edge of the inspar skin to 25.5 

inches outboard of the inspar skin on the horizontal stabilizer. 

Refer to 707, 720 NDT, Part 6, 55-10-07, Figure 1, as an accepted 

procedure.

(2) Inspect for cracks in the space between the inspar skin and the 

forward edge of the exposed upper surface of the upper chord of 

the rear spar. Inspect from the side of the body outboard towards 

Stabilizer Station 92.55. Refer to 707, 720 NDT, Part 6, 55-10-07, 

Figure 2, as an accepted procedure.

(3) Inspect for cracks in the space between the trailing edge skin and 

the aft edge of the exposed upper surface of the upper chord of the 

rear spar. Inspect from the side of the body outboard to Stabilizer 

Station 92.55. Refer to 707, 720 NDT, Part 6, 55-10-07, Figure 2 

as an accepted procedure.

(4) Inspect for cracks in the aft flange of the upper chord of the rear 
 

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spar along the fasteners common to the skin and the upper chord. 

Inspect from the inboard edge of the inspar skin to 25.5 inches 

outboard of the inspar skin on the horizontal stabilizer. Refer to 

707, 720 NDT, Part 6, 55-10-07 Figure 3, as an accepted 

procedure. 

(5) Inspect for cracks along the forward and aft edges of the exposed 

upper surface of the upper chord of the rear spar. Inspect from the 

side of the body outboard to Stabilizer Station 92.55. Refer to 707, 

720 NDT, Part 6, 55-10-07 Figure 7, as an accepted procedure. 

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 upper 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

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 of the horizontal stabilizer rear spar.

c. Do a High Frequency Eddy Current (HFEC) inspection of the web 

flanges of the upper and lower chords on the inboard and outboard ends 

of the rear spar of the left and right side horizontal stabilizer 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 service 

bulletin 707-3356 and has been repaired according to service 

bulletin 707-3356.
 

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1) For each crack that meets the limits of 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 

service bulletin 707-3356, Part III - Repair Paragraph C, 

determine if the crack still meets the limits of 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 service bulletin 707-

3356, Part III - Repair Paragraph C, but is not repaired as 

given in service bulletin 707-3356, Part III - Repair 

Paragraph C, accomplish the repair as given in 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} They 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 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.
 

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4) For a crack that meets the limits of service bulletin 707-

3356, Part III - Repair Paragraph D, accomplish the 

repair according to service bulletin 707-3356, Part III - 

Repair Paragraph D, unless already accomplished.

5) For a crack that does not meet the limits defined in 

paragraph (1)(b) through (1)(d), contact Boeing for new 

repair instructions.

(b) Determine if all 7079 upper and lower chord segments 

installed on the horizontal stabilizer have had Service Bulletin 

707-3356 Part II, Group 1 Preventative Modification done. If 

not yet accomplished, do the Service Bulletin 707-3356 Part 

II, Group 1 Preventative Modification on all 7079 chord 

segments still installed on the horizontal stabilizer.

NOTE: 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 on the outboard end of the rear spar of 

the left and right side horizontal stabilizer 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 on 

the inboard end of the rear spar of the left and right side horizontal 

stabilizer 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 on 

the outboard end of the rear spar of the left and right side horizontal 
 

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stabilizer 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 on 

the inboard end of the rear spar of the left and right side horizontal 

stabilizer between stabilizer station 92.55 and 182.55 for cracks as 

given in Figure 5.

f. Do a LFEC inspection of the forward skin flange of the lower chord on 

the inboard end of the rear spar of the left and right side horizontal 

stabilizer 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 of the horizontal stabilizer rear spar. 

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 chord with the part number given in the Material Information 

section, Paragraph 2.C.2, Parts and Materials Supplied by the Operator.

b. Contact Boeing if chord replacement instructions are needed.
 

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c. Optional.

(1) Upon completion of chord replacement, revise the data on the 

Appendix A data sheet to match the chord configuration currently 

on the airplane.

(2) Retain the updated Appendix A data sheet with the airplane 

records.
 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

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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

BAY NO.3

BALANCE

BAY NO.2

BALANCE

BAY NO.1

BALANCE BAY NO.0

BALANCE

BAY NO.5

BALANCE

BAY NO.4

BALANCE

A

A

182.55

STAB STA

137.55

STAB STA

STAB STA

92.55

47.55

STAB STA

272.55

STAB STA

STAB STA

227.55

CHORD

B

B

LEFT HORIZONTAL STABILIZER SHOWN,

RIGHT OPPOSITE

A-A

ELEVATOR

REAR SPAR

FRONT SPAR

HINGE

1

1

2

2

496234

(SHEET 1 OF 2)
 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

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BOEING SERVICE BULLETIN A3515

ALERT ALERT

The step numbers shown below agree with the numbers shown in the circle symbols in the figure. 

STEP TASK NAME IDENTIFICATION QTY MORE DATA

1 Access Balance Bay Number 2, 3, 4 and 5 - -

2 Inspect Chord Web Flange - 2 See Table 1.(a)

(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. Refer to 707, 720 NDT, Part 6, 51-00-00, Figure 4 as an accepted 

procedure.

Table 1

7079 Chord Segment Balance Bay to Inspect

Upper Inboard 2,3

Lower Inboard 2,3

Upper Outboard 4,5

Lower Outboard 4,5

B-B

2 2

FASTENER TO FARTHEST POINT OF CRACK

0.125 MAXIMUM FROM CENTERLINE OF

FASTENER TO NEAREST POINT OF CRACK

0.22 MINIMUM FROM CENTERLINE OF

FASTENER

REPAIR FASTENER

EXISTING UPPER CHORD STIFFENER

STIFFENER

CRACK

REAR SPAR UPPER CHORD

REAR VIEW

STIFFENER BAY

REPAIR AREA

WEB

D64427

(SHEET 2 OF 2)
 FIGURE 2: HORIZONTAL STABILIZER - REAR SPAR - UPPER OUTBOARD CHORD - FORWARD SKIN 

FLANGE - STABILIZER STATION 182.55 TO STABILIZER STATION 272.55 - INSPECTION

December 19, 2007

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BOEING SERVICE BULLETIN A3515

ALERT ALERT

FIGURE 2: HORIZONTAL STABILIZER - REAR SPAR - UPPER OUTBOARD CHORD - FORWARD SKIN 

FLANGE - STABILIZER STATION 182.55 TO STABILIZER STATION 272.55 - INSPECTION

The step numbers shown below agree with the numbers shown in the circle symbols in the figure. 

STEP TASK NAME IDENTIFICATION QTY MORE DATA

1 Inspect Forward Skin Flange - 2 (a)

(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. 

Refer to 707, 720 NDT, Part 6, 55-10-07, Figure 8 as an accepted procedure.

A

A

FWD

INBD

PANEL NO.4

BALANCE BAY

PANEL NO.5

BALANCE BAY

UPPER CHORD

REAR SPAR

RIGHT OPPOSITE

LEFT HORIZONTAL STABILIZER UPPER SURFACE SHOWN,

A-A

272.55

1

263.55 182.55

UPPER INSPAR SKIN

RIB

STAB STA

STAB STA STAB STA

496266

(SHEET 1 OF 1)
 FIGURE 3: HORIZONTAL STABILIZER - REAR SPAR - UPPER INBOARD CHORD - FORWARD SKIN 

FLANGE - STABILIZER STATION 92.55 TO STABILIZER STATION 182.55 - INSPECTION

December 19, 2007

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BOEING SERVICE BULLETIN A3515

ALERT ALERT

FIGURE 3: HORIZONTAL STABILIZER - REAR SPAR - UPPER INBOARD CHORD - FORWARD SKIN 

FLANGE - STABILIZER STATION 92.55 TO STABILIZER STATION 182.55 - INSPECTION

The step numbers shown below agree with the numbers shown in the circle symbols in the figure. 

STEP TASK NAME IDENTIFICATION QTY MORE DATA

1 Inspect Forward Skin Flange - 2 (a)

(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. 

Refer to 707, 720 NDT, Part 6, 55-10-07, Figure 8 as an accepted procedure.

A

A

BALANCE BAY

FWD PANEL NO.2

INBD

UPPER CHORD

REAR SPAR

PANEL NO.3

BALANCE BAY

RIGHT OPPOSITE

LEFT HORIZONTAL STABILIZER UPPER SURFACE SHOWN,

A-A

173.55

STAB STA

1

INSPAR SKIN

182.55

STAB STA

UPPER 92.55

STAB STA

496279

(SHEET 1 OF 1)
 FIGURE 4: HORIZONTAL STABILIZER - REAR SPAR - LOWER OUTBOARD CHORD - FORWARD SKIN 

FLANGE - STABILIZER STATION 182.55 TO STABILIZER STATION 272.55 - INSPECTION

December 19, 2007

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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

The step numbers shown below agree with the numbers shown in the circle symbols in the figure. 

STEP TASK NAME IDENTIFICATION QTY MORE DATA

1 Inspect Forward Skin Flange - 2 (a)

(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. 

Refer to 707, 720 NDT, Part 6, 55-10-07, Figure 8 as an accepted procedure.

A

A

FWD

INBD

LOWER CHORD

REAR SPAR

LEFT HORIZONTAL STABILIZER LOWER SURFACE SHOWN,

RIGHT OPPOSITE

A-A

1

LOWER

INSPAR SKIN

182.55

STAB STA

263.55

STAB STA 272.55

STAB STA

496285

(SHEET 1 OF 1)
 FIGURE 5: HORIZONTAL STABILIZER - REAR SPAR - LOWER INBOARD CHORD - FORWARD SKIN 

FLANGE - STABILIZER STATION 92.55 TO STABILIZER STATION 182.55 - INSPECTION

December 19, 2007

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BOEING SERVICE BULLETIN A3515

ALERT ALERT

FIGURE 5: HORIZONTAL STABILIZER - REAR SPAR - LOWER INBOARD CHORD - FORWARD SKIN 

FLANGE - STABILIZER STATION 92.55 TO STABILIZER STATION 182.55 - INSPECTION

The step numbers shown below agree with the numbers shown in the circle symbols in the figure. 

STEP TASK NAME IDENTIFICATION QTY MORE DATA

1 Inspect Forward Skin Flange - 2 (a) (b)

(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.

Refer to 707, 720 NDT, Part 6, 55-10-07, Figure 8 as an accepted procedure.

(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.

A

A

LOWER CHORD

REAR SPAR

INBD

FWD

1

LOWER

INSPAR SKIN

92.55

STAB STA

173.55

STAB STA

182.55

STAB STA

LEFT HORIZONTAL STABILIZER LOWER SURFACE SHOWN,

A-A

RIGHT OPPOSITE

496290

(SHEET 1 OF 1)
 FIGURE 6: HORIZONTAL STABILIZER - REAR SPAR - LOWER INBOARD CHORD - FORWARD SKIN 

FLANGE - STABILIZER STATION -13.179 TO STABILIZER STATION 92.55 - INSPECTION

December 19, 2007

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BOEING SERVICE BULLETIN A3515

ALERT ALERT

FIGURE 6: HORIZONTAL STABILIZER - REAR SPAR - LOWER INBOARD CHORD - FORWARD SKIN 

FLANGE - STABILIZER STATION -13.179 TO STABILIZER STATION 92.55 - INSPECTION

The step numbers shown below agree with the numbers shown in the circle symbols in the figure. 

STEP TASK NAME IDENTIFICATION QTY MORE DATA

1 Inspect Forward Skin Flange - 2 (a) (b)

(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. 

Refer to 707, 720 NDT, Part 6, 55-10-07, Figure 8 as an accepted procedure.

(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.

A

A

LOWER CHORD

REAR SPAR

INBD

FWD

STAB STA

-13.179 1

STAB STA

92.55

LOWER

INSPAR SKIN

STAB STA

83.55

LEFT HORIZONTAL STABILIZER LOWER SURFACE SHOWN,

A-A

RIGHT OPPOSITE

496349

(SHEET 1 OF 1)
 APPENDIX A: CONFIGURATION VERIFICATION - INSPECTION RESULTS FORM - MATERIAL DATA

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BOEING SERVICE BULLETIN A3515

ALERT ALERT

APPENDIX A: CONFIGURATION VERIFICATION - INSPECTION RESULTS FORM - MATERIAL DATA

AIRPLANE REGISTRY: FLIGHT HOURS: FLIGHT CYCLES:

LEFT SIDE Horizontal Stabilizer

Stabilizer Part Number (a): Stabilizer Serial Number (a):

Spar Chord 

Segment

Location Spar Chord Material (b):

(from Part 2 - Configuration Check)

Upper Inboard Side of Body to SSTA 182.55

Lower Inboard Side of Body to SSTA 182.55

Upper Outboard SSTA 182.55 to Stabilizer Tip

Lower Outboard SSTA 182.55 to Stabilizer Tip

RIGHT SIDE Horizontal Stabilizer

Stabilizer Part Number (a): Stabilizer Serial Number (a):

Spar Chord 

Segment

Location Spar Chord Material (b)

(from Part 2 - Configuration Check)

Upper Inboard Side of Body to SSTA 182.55

Lower Inboard Side of Body to SSTA 182.55

Upper Outboard SSTA 182.55 to Stabilizer Tip

Lower Outboard SSTA 182.55 to Stabilizer Tip

(a) Record the horizontal stabilizer part number and serial number as recorded on the data 

plate.

(b) Record spar chord material, 7079-T6 or 7075-T73511, as determined from maintenance 

record review, or electrical conductivity test. For the electrical conductivity test refer to 

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. 

Comments: