# Boeing Special Attention Service Bulletin 727-55-0095: No revision named

- Rights: © The Boeing Company. Filed by the FAA in regulations.gov docket FAA-2013-0361; AD 2013-15-11 incorporates this document by reference. Not covered by OpenAirDocs’ CC0 dedication.
- Document: [Boeing Special Attention Service Bulletin 727-55-0095](https://openairdocs.org/service-documents/boeing/sb-727-55-0095.md)
- Title as filed: U.S. DOT/FAA - SB-727-55-0095-00
- Pages: 27
- PDF: https://openairdocs.org/files/sha256/8a/e8/8ae8a03c2df3d152f0a63b2165a7de2fa097c0e7d7520b62eef58a6dcb92e05a
- Page: https://openairdocs.org/service-documents/boeing/sb-727-55-0095/file/8ae8a03c2df3

## Text

Some pages are OCR from a scan. OCR can misread letters and numbers. Each page's text from the PDF; open the PDF at a page with #page=N.

### Page 1

Commercial 
Airplanes
727
Service Bulletin
SPECIAL ATTENTION
Number: 727-55-0095
Original Issue: September 24, 2012
ATA System: 5500
SUBJECT: STABILIZERS - Vertical Stabilizer - Fin Closure Rib - Chord Inspection
Export of this technology is controlled under the United States Export Administration Regulations (EAR) (15
CFR 300-774). An export license may be required before it is used for development, production or use by foreign
persons from specific countries. The controller of this data has the individual responsibility to abide by all export
laws.
9E991ECCN:
BOEING PROPRIETARY, CONFIDENTIAL AND/OR TRADE SECRET
Copyright © 2012 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Unpublished Work.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, KDC-10, MD-10, MD-11, MD-80, MD-88, MD-90, P-8A, 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. BOEING is a trademark of Boeing Management
Company.
Original Issue: September 24, 2012
727-55-0095
1 of 27
4.0

### Page 2

Export Controlled ECCN: 9E991 - BOEING
PROPRIETARY - Copyright © Unpublished
Work - See page 1 for details.
Original Issue: September 24, 2012
727-55-0095
2 of 27
BOEING SERVICE BULLETIN 727-55-0095
BLANK PAGE

### Page 3

Table of Contents
Summary ...................................................... 5
1. PLANNING INFORMATION ........................................ 9
A. Effectivity ................................................ 9
1. Airplanes ............................................. 9
2. Spares Affected ........................................ 1 3
B. Concurrent Requirements ...................................... 1 3
C. Reason ................................................ 1 4
D. Description .............................................. 1 4
E. Compliance .............................................. 1 5
F. Approval ............................................... 1 5
G. Manpower .............................................. 1 5
H. Weight and Balance Changes .................................... 1 6
I. Electrical Load Data ......................................... 1 6
J. References .............................................. 1 6
1. Existing Data: ......................................... 1 6
2. Data Supplied with this Service Bulletin: ........................... 1 6
3. Installation Drawings Used in the Preparation of this Service Bulletin: ........... 1 6
K. Publications Affected ........................................ 1 6
L. Interchangeability and Intermixability of Parts ........................... 1 7
M. Software Accomplishment Summary ................................ 1 7
2. MATERIAL INFORMATION ........................................ 1 9
A. Material - Price and Availability ................................... 1 9
B. Industry Support Information .................................... 1 9
C. Parts Necessary for Each Airplane ................................. 1 9
1. Kits/Parts ............................................ 1 9
2. Parts and Materials Supplied by the Operator ........................ 1 9
3. Parts Modified and Reidentified ................................ 1 9
4. Parts Removed and Not Replaced .............................. 2 0
D. Parts Necessary to Change Spares ................................. 2 0
E. Special Tooling - Price and Availability ............................... 2 0
F. Special Tooling Necessary to do this Service Bulletin ....................... 2 0
3. ACCOMPLISHMENT INSTRUCTIONS .................................. 2 1
A. GENERAL INFORMATION ..................................... 2 1
B. WORK INSTRUCTIONS ....................................... 2 2
FIGURE 1: VERTICAL STABILIZER - LEFT SIDE FIN CLOSURE RIB CHORD INSPECTION .... 2 4
FIGURE 2: VERTICAL STABILIZER - RIGHT SIDE FIN CLOSURE RIB CHORD INSPECTION . . . 26
Export Controlled ECCN: 9E991 - BOEING
PROPRIETARY - Copyright © Unpublished
Work - See page 1 for details.
Original Issue: September 24, 2012
727-55-0095
3 of 27
BOEING SERVICE BULLETIN 727-55-0095

### Page 4

Export Controlled ECCN: 9E991 - BOEING
PROPRIETARY - Copyright © Unpublished
Work - See page 1 for details.
Original Issue: September 24, 2012
727-55-0095
4 of 27
BOEING SERVICE BULLETIN 727-55-0095
BLANK PAGE

### Page 5

Commercial 
Airplanes
727
Service Bulletin
SPECIAL ATTENTION
SummaryNumber: 727-55-0095Original Issue: September 24, 2012
ATA System: 5500
SUBJECT: STABILIZERS - Vertical Stabilizer - Fin Closure Rib - Chord Inspection
BOEING RECOMMENDS THAT EACH OPERATOR EXAMINE THIS SERVICE BULLETIN IMMEDIATELY.
CONCURRENT REQUIREMENTS
None.
BACKGROUND
This service bulletin gives instructions to inspect the left side and right side chords of the fin closure rib for
cracking or corrosion. The fin closure rib is located at the top of the vertical fin structure. The chords of the fin
closure rib support the horizontal stabilizer hinge fittings. If the work in this service bulletin is not done, widespread
cracking in the chords may weaken the fin closure rib structure which could result in loss of airplane control due
to lack of horizontal stabilizer support.
One operator reported finding a crack on the left side chord of the fin closure rib during a routine maintenance
inspection. The crack measured a maximum of 2.4 inches long and it ran along the length of the chord. The
airplane had accumulated 5,303 flight cycles and 11,669 flight hours when the crack was found. Cracking at
this location is the result of intergranular stress corrosion caused by the material properties of 2024-T351
extrusion from which the closure rib chord is made. This material becomes vulnerable after the surface finishes
begin to break down as a result of normal in-service aging.
A fleet history search revealed that this occurrence is the first report of intergranular cracking of the chords. The
Corrosion Prevention and Control Program (CPCP) and Maintenance Planning Data (MPD) documentation for
727 airplanes both contain visual inspections of the chords, but no NDT inspections. Accomplishment of the
NDT and visual inspections in this service bulletin will make sure that any crack or corrosion in the left side or
right side chords of the fin closure rib is detected.
Boeing Service Related Problem (SRP) 727-SRP-55-0050 is related to this service bulletin.
Boeing Fleet Team Digest (FTD) 727 FTD 55-10001 is related to this service bulletin.
This table is provided to operators for planning purposes only. Refer to the applicable sections for more
information.
ReferenceAffectedPlanning Data
Paragraph 1.A.2., Spares AffectedNoSpares Affected
Paragraph 1.E., ComplianceNoAD Related
Export Controlled ECCN: 9E991 - BOEING
PROPRIETARY - Copyright © Unpublished
Work - See page 1 for details.
Original Issue: September 24, 2012
727-55-0095
5 of 27

### Page 6

ReferenceAffectedPlanning Data
Paragraph 1.H., Weight and Balance ChangesNoWeight and Balance Change
Paragraph 1.I., Electrical Load DataNoElectrical Load Changed
Paragraph 1.K., Publications AffectedNoPublications Affected
Paragraph 1.K., Publications AffectedNoAirplane Flight Operations Affected (Flight Crew
Operations Manual and/or FAA Approved Air-
plane Flight Manual)
Paragraph 2.C.1., Kits/PartsNoKits/Parts Required
Paragraph 2.C.2., Parts and Materials Supplied
by the Operator
YesOperator Supplied Material
Paragraph 2.F., Special Tooling Necessary to
do this Service Bulletin
NoSpecial Tooling Required
ACTION
Get access to the left side and right side chords of the fin closure rib by opening access panels at the fin closure
rib. Do a detailed inspection for any crack or corrosion and High Frequency Eddy Current (HFEC) inspections
for any crack in the left side and right side chords. If any crack or corrosion is found, contact Boeing for repair
or replacement instructions and do the work instructed by Boeing. Do repeat inspections at the interval given in
Paragraph 1.E., Compliance.
EFFECTIVITY
All 727, 727-100, 727-100C, 727-200, 727-200F, 727C airplanes. Refer to Paragraph 1.A.1., Airplanes, for the
list of affected airplanes.
COMPLIANCE
Refer to Paragraph 1.E., Compliance.
INDUSTRY SUPPORT INFORMATION
Boeing warranty remedies are not available for the inspection procedures given in this service bulletin.
MANPOWER
Refer to Paragraph 1.G., Manpower.
Elapsed HoursTotal Task HoursAirplanes
11.0017.00Group 1
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: September 24, 2012
727-55-0095
6 of 27
BOEING SERVICE BULLETIN 727-55-0095

### Page 7 (OCR)

BOEING SERVICE BULLETIN 727-55-0095
TYPICAL
CORROSION
DO A DETAILED INSPECTION FOR ANY
CRACK OR CORROSION AND A HIGH
FREQUE  Y CURRENT INSPECTION
FOR ANY CR  N THE LEFT SIDE AND
RIGHT SIDE  DS OF THE FIN CLOSURE
RIB. IF  CORROSION IS
FOUND  OR REPAIR OR
REPLACE  ONS AND DO
THE WORK II  USTRUC  BOEING
Original Issue: September 24, 2012
Export Controlled ECCN: 9E991 - BOEING  727-55-0095
PROPRIETARY - Copyright © Unpublished
Work - See page 1 for details.  7 of 27

### Page 8

Export Controlled ECCN: 9E991 - BOEING
PROPRIETARY - Copyright © Unpublished
Work - See page 1 for details.
Original Issue: September 24, 2012
727-55-0095
8 of 27
BOEING SERVICE BULLETIN 727-55-0095
BLANK PAGE

### Page 9

Commercial 
Airplanes
727
Service Bulletin
SPECIAL ATTENTION
Number: 727-55-0095
Original Issue: September 24, 2012
ATA System: 5500
SUBJECT: STABILIZERS - Vertical Stabilizer - Fin Closure Rib - Chord Inspection
BOEING RECOMMENDS THAT EACH OPERATOR EXAMINE THIS SERVICE BULLETIN IMMEDIATELY.
1.    PLANNING INFORMATION
A. Effectivity
1. Airplanes
Refer to Service Bulletin Index D6-9825 Part 3 for Airplane Variable Number, Line Number, and
Serial Number data.
This service bulletin is for the airplane(s) shown below.
DESCRIPTIONCONFIGURATIONGROUP
All 727, 727-100, 727-100C, 727-200, 727-200F, 727C airplanes.-1
Airplane Models:
727, 727-100, 727-100C, 727-200, 727-200F, 727C
GroupVariable Number
1E0001 - E0042
1E0101 - E0140
1E0201 - E0216
1E0301 - E0351
1E0401 - E0423
1E3001 - E3006
1E3011 - E3014
1E3021 - E3040
1E3059
Export Controlled ECCN: 9E991 - BOEING
PROPRIETARY - Copyright © Unpublished
Work - See page 1 for details.
Original Issue: September 24, 2012
727-55-0095
9 of 27

### Page 10

GroupVariable Number
1E3061 - E3077
1E3101 - E3103
1E3111 - E3118
1E3141 - E3152
1E3171 - E3177
1E3201 - E3206
1E3221 - E3224
1E3241 - E3290
1E3341 - E3350
1E3401 - E3421
1E3451 - E3452
1E3471 - E3474
1E3501 - E3513
1E3516 - E3523
1E3551 - E3553
1E3571 - E3578
1E3601 - E3604
1E3621 - E3622
1E3651 - E3655
1E3677
1E3681 - E3684
1E3701 - E3704
1E3751 - E3755
1E3781 - E3784
1E5001 - E5011
1E5031 - E5068
1E5101 - E5116
1E5141 - E5143
1E5161 - E5164
1E5201 - E5203
1E5221 - E5245
1E5251 - E5252
1E5271 - E5281
Export Controlled ECCN: 9E991 - BOEING
PROPRIETARY - Copyright © Unpublished
Work - See page 1 for details.
Original Issue: September 24, 2012
727-55-0095
10 of 27
BOEING SERVICE BULLETIN 727-55-0095

### Page 11

GroupVariable Number
1E5301 - E5306
1E5351 - E5353
1E5381 - E5382
1E5401 - E5424
1E5426 - E5429
1E5433
1E5435
1E5451 - E5455
1E5481 - E5483
1E5501 - E5502
1QA001 - QA046
1QA051 - QA099
1QA101 - QA199
1QA201 - QA225
1QA301 - QA349
1QA351 - QA376
1QA378
1QA401 - QA499
1QA501 - QA537
1QA551 - QA579
1QA581 - QA585
1QA601 - QA688
1QA701 - QA753
1QA801 - QA805
1QA851 - QA899
1QA901 - QA946
1QA949
1QB001 - QB002
1QB031 - QB049
1QB051 - QB068
1QB101 - QB110
1QB114 - QB119
1QB121 - QB149
Export Controlled ECCN: 9E991 - BOEING
PROPRIETARY - Copyright © Unpublished
Work - See page 1 for details.
Original Issue: September 24, 2012
727-55-0095
11 of 27
BOEING SERVICE BULLETIN 727-55-0095

### Page 12

GroupVariable Number
1QB151 - QB158
1QB201 - QB220
1QB301 - QB316
1QB351 - QB352
1QB401 - QB407
1QB451 - QB458
1QB501 - QB575
1QB601 - QB629
1QB651
1QB701 - QB705
1QB801 - QB810
1QB901 - QB904
1QD001 - QD012
1QD031 - QD046
1QD085 - QD088
1QD101 - QD105
1QD121 - QD127
1QD141 - QD149
1QD161 - QD164
1QD191 - QD192
1QD201 - QD239
1QD281 - QD284
1QD301 - QD305
1QD321 - QD330
1QD351
1QD401 - QD403
1QD407
1QD410
1QD421 - QD427
1QD441 - QD453
1QD471 - QD475
1QD501 - QD518
1QD551 - QD558
Export Controlled ECCN: 9E991 - BOEING
PROPRIETARY - Copyright © Unpublished
Work - See page 1 for details.
Original Issue: September 24, 2012
727-55-0095
12 of 27
BOEING SERVICE BULLETIN 727-55-0095

### Page 13

GroupVariable Number
1QD571 - QD572
1QD581 - QD583
1QD601 - QD607
1QD621 - QD624
1QD641
1QD661 - QD663
1QD681 - QD685
1QD691 - QD692
1QD701 - QD702
1QD711 - QD717
1QD741
1QD761 - QD769
1QD781 - QD782
1QD791
1QD801 - QD804
1QD821 - QD828
1QD901 - QD910
1QD931 - QD932
1QD951 - QD954
1QD971 - QD973
1QD991 - QD992
1QE001 - QE002
1QL001 - QL008
1QL031 - QL032
1QL081
1QL501 - QL515
2. Spares Affected
None.
B. Concurrent Requirements
None.
Export Controlled ECCN: 9E991 - BOEING
PROPRIETARY - Copyright © Unpublished
Work - See page 1 for details.
Original Issue: September 24, 2012
727-55-0095
13 of 27
BOEING SERVICE BULLETIN 727-55-0095

### Page 14

C. Reason
This service bulletin gives instructions to inspect the left side and right side chords of the fin closure
rib for cracking or corrosion. The fin closure rib is located at the top of the vertical fin structure. The
chords of the fin closure rib support the horizontal stabilizer hinge fittings. If the work in this service
bulletin is not done, widespread cracking in the chords may weaken the fin closure rib structure which
could result in loss of airplane control due to lack of horizontal stabilizer support.
One operator reported finding a crack on the left side chord of the fin closure rib during a routine
maintenance inspection. The crack measured a maximum of 2.4 inches long and it ran along the length
of the chord. The airplane had accumulated 5,303 flight cycles and 11,669 flight hours when the crack
was found. Cracking at this location is the result of intergranular stress corrosion caused by the material
properties of 2024-T351 extrusion from which the closure rib chord is made. This material becomes
vulnerable after the surface finishes begin to break down as a result of normal in-service aging.
A fleet history search revealed that this occurrence is the first report of intergranular cracking of the
chords. The Corrosion Prevention and Control Program (CPCP) and Maintenance Planning Data (MPD)
documentation for 727 airplanes both contain visual inspections of the chords, but no NDT inspections.
Accomplishment of the NDT and visual inspections in this service bulletin will make sure that any crack
or corrosion in the left side or right side chords of the fin closure rib is detected.
Boeing Service Related Problem (SRP) 727-SRP-55-0050 is related to this service bulletin.
Boeing Fleet Team Digest (FTD) 727 FTD 55-10001 is related to this service bulletin.
D. Description
Get access to the left side and right side chords of the fin closure rib by opening access panels at the
fin closure rib. Do a detailed inspection for any crack or corrosion and High Frequency Eddy Current
(HFEC) inspections for any crack in the left side and right side chords. If any crack or corrosion is found,
contact Boeing for repair or replacement instructions and do the work instructed by Boeing. Do repeat
inspections at the interval given in Paragraph 1.E., Compliance.
The work in this service bulletin is done in the maintenance zone(s) given below.
Affected Maintenance Zones
ZoneModel
3-97727, 727-100, 727-100C, 727-
200, 727-200F, 727C
Export Controlled ECCN: 9E991 - BOEING
PROPRIETARY - Copyright © Unpublished
Work - See page 1 for details.
Original Issue: September 24, 2012
727-55-0095
14 of 27
BOEING SERVICE BULLETIN 727-55-0095

### Page 15

E. Compliance
Table 1: Vertical Stabilizer - Fin Closure Rib Chord Inspection
Repeat Interval
(Not to Exceed)
Compliance TimeActionCondition
26 months.Within 24 months
after the original is-
sue date of this
service bulletin.
Do a detailed inspection for
any crack or corrosion and
High Frequency Eddy Current
(HFEC) inspections for any
crack in the left side and right
side chords of the fin closure
rib in accordance with Accom-
plishment Instructions para-
graph 3.B. Part 2.
All airplanes
-Before further
flight.
Contact Boeing for repair or
replacement instructions and
do the work instructed by
Boeing.
Any crack or corrosion
found.
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.
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 inspect the work
 Time to cure the materials
 Time to make the parts
 Time to find the tools.
Elapsed HoursTask HoursNumber of PersonsTask
1.001.001Preparation
Export Controlled ECCN: 9E991 - BOEING
PROPRIETARY - Copyright © Unpublished
Work - See page 1 for details.
Original Issue: September 24, 2012
727-55-0095
15 of 27
BOEING SERVICE BULLETIN 727-55-0095

### Page 16

Elapsed HoursTask HoursNumber of PersonsTask
1.501.501Open Access
3.006.002FIGURE 1
3.006.002FIGURE 2
1.001.001Restoration
1.501.501Close Access
11.0017.00TOTAL FOR EACH AIRPLANE
H. Weight and Balance Changes
None.
I. Electrical Load Data
Not applicable.
J. References
1. Existing Data:
a. Boeing Service Related Problem (SRP) 727-SRP-55-0050
b. Standard Overhaul Practices Manual (SOPM) 20-41-05
c. 727 Aircraft Maintenance Manual (AMM) 12-30-05, 27-30-00
d. 727 Fleet Team Digest (FTD) 55-10001
e. 727 Non-Destructive Testing (NDT) Manual Part 6, 51-00-00, Figure 4, Figure 23.
f. Boeing Service Letter 727-SL-51-041.
2. Data Supplied with this Service Bulletin:
None.
3. Installation Drawings Used in the Preparation of this Service Bulletin:
None.
K. Publications Affected
1. Publications:
None.
2. Damage Tolerance Based Structural Inspections:
Export Controlled ECCN: 9E991 - BOEING
PROPRIETARY - Copyright © Unpublished
Work - See page 1 for details.
Original Issue: September 24, 2012
727-55-0095
16 of 27
BOEING SERVICE BULLETIN 727-55-0095

### Page 17

Boeing has evaluated the repairs and/or changes in this service bulletin for effects on Fatigue
Critical Structure (FCS) and for changes to Damage Tolerance Inspections (DTI) required in the
Maintenance Program. This service bulletin affects FCS but no new DTIs are necessary.
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: September 24, 2012
727-55-0095
17 of 27
BOEING SERVICE BULLETIN 727-55-0095

### Page 18

Export Controlled ECCN: 9E991 - BOEING
PROPRIETARY - Copyright © Unpublished
Work - See page 1 for details.
Original Issue: September 24, 2012
727-55-0095
18 of 27
BOEING SERVICE BULLETIN 727-55-0095
BLANK PAGE

### Page 19

2.    MATERIAL INFORMATION
A. Material - Price and Availability
Boeing can supply the kits/parts shown in Paragraph 2.C., Parts Necessary for Each Airplane. Operators
are encouraged to share schedule requirements with Boeing for incorporation of the service bulletin.
The kits/parts are subject to the terms and conditions of the Boeing standard purchase order
acknowledgment. Prices are in United States Dollars. Terms: Net 30 days.
Reference this service bulletin and submit your purchase order by one of these methods:
1. Order on-line via ATA Spec 2000 or The Boeing PART Page
2. Fax to (206) 662-7145
REFER TO THE BOEING PART PAGE ON MYBOEINGFLEET.COM OR CONTACT FIRST RESPONDER
AT FR@BOEING.COM FOR THE LATEST REORDER LEAD TIME (ROLT) AND PRICE INFORMATION
Unit Price as of
the date of this
Service Bulletin
(US Dollars)
ROLT as of the
date of this Ser-
vice Bulletin (Cal-
endar Days)
NameNumber
49,066.00-Chord LH65-16804-1
49,066.00-Chord RH65-16804-2
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
NotesNameQTYPart Number / Speci-
fication
(a)Corrosion Inhibiting Compound5 ozBMS 3-23, Type 2
-Chord LH165-16804-1
-Chord RH165-16804-2
(a) Refer to the Qualified Products List at the end of the Boeing Material Specification (BMS)
for supplier data.
3. Parts Modified and Reidentified
None.
Export Controlled ECCN: 9E991 - BOEING
PROPRIETARY - Copyright © Unpublished
Work - See page 1 for details.
Original Issue: September 24, 2012
727-55-0095
19 of 27
BOEING SERVICE BULLETIN 727-55-0095

### Page 20

4. Parts Removed and Not Replaced
None.
D. Parts Necessary to Change Spares
None.
E. Special Tooling - Price and Availability
None.
F. Special Tooling Necessary to do this Service Bulletin
No special tools or equipment are necessary to do the change in this service bulletin. But, maintenance
and overhaul tools in the manuals given in Paragraph 1.J., References, can be necessary. Examine
operator tool supply to make sure all necessary tools are available.
Export Controlled ECCN: 9E991 - BOEING
PROPRIETARY - Copyright © Unpublished
Work - See page 1 for details.
Original Issue: September 24, 2012
727-55-0095
20 of 27
BOEING SERVICE BULLETIN 727-55-0095

### Page 21

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
– 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.
5. A Detailed Inspection is defined as: An intensive examination of a specific item,
installation, or assembly to detect damage, failure, or irregularity. Available lighting
is normally supplemented with a direct source of good lighting at an intensity deemed
appropriate. Inspection aids such as mirrors, magnifying lenses, etc. may be
necessary. Surface cleaning and elaborate procedures may be required.
6. 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.
7. Boeing Service Letter 727-SL-51-041, 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.
8. 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.
9. Shaded areas in Figures are reference only. Shaded areas in Figures may look
different than your airplane.
Export Controlled ECCN: 9E991 - BOEING
PROPRIETARY - Copyright © Unpublished
Work - See page 1 for details.
Original Issue: September 24, 2012
727-55-0095
21 of 27
BOEING SERVICE BULLETIN 727-55-0095

### Page 22

B. WORK INSTRUCTIONS
1. PART 1 - PREPARATION AND ACCESS
a. Place the horizontal stabilizer leading edge in the full down position.
b. Position the horizontal stabilizer trim cutout switches to CUTOUT.
c. Depressurize the elevator hydraulic systems A and B. Refer to 727 AMM 27-30-00 as an
accepted procedure.
d. Open all autopilot circuit breakers on the P18 panel and install DO-NOT-CLOSE identifiers.
e. Get access to the fin upper closure rib by removing access panels 9705, 9706, 9710, 9711,
9777 and 9778. Refer to 727 AMM 12-30-05 as an accepted procedure.
2. PART 2 - INSPECTION
a. Prepare the area for safe work. Refer to Part 1 as an accepted procedure.
b. Do a detailed inspection for any crack or corrosion and High Frequency Eddy Current (HFEC)
inspections for any crack in the left side chord of the fin closure rib in accordance with FIGURE
1.
(1) If any crack or corrosion is found, do one of the options that follow:
(a) Contact Boeing for replacement instructions and replace the left side chord with a
new or serviceable left side chord, part number 65-16804-1, in accordance with the
instructions provided by Boeing.
(b) Contact Boeing for repair instructions and do the work instructed by Boeing.
(2) If no cracking or corrosion is found, do repeat inspections at the interval given in Paragraph
1.E., Compliance.
c. Do a detailed inspection for any crack or corrosion and HFEC inspections for any crack in the
right side chord of the fin closure rib in accordance with FIGURE 2.
(1) If any crack or corrosion is found, do one of the options that follow:
(a) Contact Boeing for replacement instructions and replace the right side chord with a
new or serviceable right side chord, part number 65-16804-2, in accordance with the
instructions provided by Boeing.
(b) Contact Boeing for repair instructions and do the work instructed by Boeing.
(2) If no cracking or corrosion is found, do repeat inspections at the interval given in Paragraph
1.E., Compliance.
d. Apply BMS 3-23, Type 2 Corrosion Inhibiting Compound to exposed areas of the fin closure
rib. Refer to SOPM 20-41-05 as an accepted procedure.
e. Put the airplane back to a serviceable condition. Refer to Part 3 as an accepted procedure.
Export Controlled ECCN: 9E991 - BOEING
PROPRIETARY - Copyright © Unpublished
Work - See page 1 for details.
Original Issue: September 24, 2012
727-55-0095
22 of 27
BOEING SERVICE BULLETIN 727-55-0095

### Page 23

3. PART 3 - RESTORATION AND CLOSE ACCESS
a. Close access panels 9705, 9706, 9710, 9711, 9777 and 9778. Refer to 727 AMM 12-30-05
as an accepted procedure.
b. Close all autopilot circuit breakers on the P18 panel and remove DO-NOT-CLOSE identifiers.
c. Pressurize the elevator hydraulic systems A and B. Refer to 727 AMM 27-30-00 as an accepted
procedure.
d. Position the horizontal stabilizer trim cutout switches to NORMAL.
e. Put the airplane back to a serviceable condition.
Export Controlled ECCN: 9E991 - BOEING
PROPRIETARY - Copyright © Unpublished
Work - See page 1 for details.
Original Issue: September 24, 2012
727-55-0095
23 of 27
BOEING SERVICE BULLETIN 727-55-0095

### Page 24 (OCR)

BOEING SERVICE BULLETIN 727-55-0095
TYPICAL
CORROSION
LEFT SIDE
CHORD
FIN
CLOSURE
RIB WEB
ONLY CLOSURE RIB
SHOWN FOR CLARITY
A-A  2131133
FIGURE 1: VERTICAL STABILIZER - LEFT SIDE FIN CLOSURE RIB CHORD INSPECTION
(SHEET 1 OF 2)
Original Issue: September 24, 2012
Export Controlled ECCN: 9E991 - BOEING  PROPRIETARY - Copyright © Unpublished  727-55-0095
Work - See page 1 for details.  24 of 27

### Page 25

The step numbers shown below agree with the numbers shown in the circle symbols in the figure. The QTY
numbers shown below are the number of parts necessary for one side of the airplane.
More DataQtyIdentificationNameTaskStep
(a)165-16804-1Left Side ChordInspect1
(b) (f)165-16804-1Left Side ChordInspect2
(c) (g)165-16804-1Left Side ChordInspect3
(d)165-16804-1Left Side ChordInspect4
(e)165-16804-1Left Side ChordInspect5
(a) Do a detailed inspection for any crack or corrosion in the left side chord of the fin closure rib.
(b) Do a detailed inspection for any crack or corrosion in the internal surfaces of the left side chord of the fin
closure rib. A borescope can be used for the inspection of the internal surfaces of the chord. Access to
internal surfaces can be achieved through the two access holes in the fin closure rib web.
(c) Do a High Frequency Eddy Current (HFEC) transverse scan inspection for any crack in the chord lower
radii in accordance with 727 NDT Part 6, 51-00-00, Figure 4 or Figure 23. Access to internal surfaces can
be achieved through the two access holes in the fin closure rib web. A flexible shaft pencil probe and vi-
sual aids such as borescope and flashlight can be used as necessary to assist with the inspection of in-
ternal surfaces. At any location where the radius cannot be scanned because it is covered by structure,
no HFEC inspection is required.
(d) Do a HFEC parallel scan inspection for any crack in the chord upper radius in accordance with 727 NDT
Part 6, 51-00-00, Figure 4 or Figure 23. At any location where the upper radius cannot be scanned because
it is covered by structure, no HFEC inspection is required.
(e) Do a HFEC inspection for any crack in the upper edge of the chord in accordance with 727 NDT Part 6,
51-00-00, Figure 4 or Figure 23. At any location where the upper edge cannot be scanned because it is
covered by structure, no HFEC inspection is required.
(f) For the borescope or video probe inspection of the forward 10 inches of the chord, it is necessary to attach
a dowel rod to the borescope or video probe if a flexible borescope or video probe is used. A sleeve (tube)
for the flexible borescope or video probe can be used instead of a dowel rod to make the flexible borescope
or video probe rigid.
(g) A 90 degree pencil probe with a minimum shaft length of 8 inches is required to reach the forward most
inspection area on the chord. Alternatively, a shorter 90 degree probe can be used with a dowel rod at-
tached to the handle. A shorter 90 degree probe can be used for the remaining inspection areas.
FIGURE 1: VERTICAL STABILIZER - LEFT SIDE FIN CLOSURE RIB CHORD INSPECTION
(SHEET 2 OF 2)
Export Controlled ECCN: 9E991 - BOEING
PROPRIETARY - Copyright © Unpublished
Work - See page 1 for details.
Original Issue: September 24, 2012
727-55-0095
25 of 27
BOEING SERVICE BULLETIN 727-55-0095

### Page 26 (OCR)

BOEING SERVICE BULLETIN 727-55-0095
TYPICAL
CORROSION
RIGHT SIDE
CHORD
FIN
CLOSURE
RIB WEB
ONLY CLOSURE RIB
SHOWN FOR CLARITY
A-A  2131113
FIGURE 2: VERTICAL STABILIZER - RIGHT SIDE FIN CLOSURE RIB CHORD INSPECTION
(SHEET 1 OF 2)
Original Issue: September 24, 2012
Export Controlled ECCN: 9E991 - BOEING  PROPRIETARY - Copyright © Unpublished  727-55-0095
Work - See page 1 for details.  26 of 27

### Page 27

The step numbers shown below agree with the numbers shown in the circle symbols in the figure. The QTY
numbers shown below are the number of parts necessary for one side of the airplane.
More DataQtyIdentificationNameTaskStep
(a)165-16804-2Right Side ChordInspect1
(b) (f)165-16804-2Right Side ChordInspect2
(c) (g)165-16804-2Right Side ChordInspect3
(d)165-16804-2Right Side ChordInspect4
(e)165-16804-2Right Side ChordInspect5
(a) Do a detailed inspection for any crack or corrosion in the right side chord of the fin closure rib.
(b) Do a detailed inspection for any crack or corrosion in the internal surfaces of the right side chord of the
fin closure rib. A borescope can be used for the inspection of the internal surfaces of the chord. Access
to internal surfaces can be achieved through the two access holes in the fin closure rib web.
(c) Do a High Frequency Eddy Current (HFEC) transverse scan inspection for any crack in the chord lower
radii in accordance with 727 NDT Part 6, 51-00-00, Figure 4 or Figure 23. Access to internal surfaces can
be achieved through the two access holes in the fin closure rib web. A flexible shaft pencil probe and vi-
sual aids such as borescope and flashlight can be used as necessary to assist with the inspection of in-
ternal surfaces. At any location where the radius cannot be scanned because it is covered by structure,
no HFEC inspection is required.
(d) Do a HFEC parallel scan inspection for any crack in the chord upper radius in accordance with 727 NDT
Part 6, 51-00-00, Figure 4 or Figure 23. At any location where the upper radius cannot be scanned because
it is covered by structure, no HFEC inspection is required.
(e) Do a HFEC inspection for any crack in the upper edge of the chord in accordance with 727 NDT Part 6,
51-00-00, Figure 4 or Figure 23. At any location where the upper edge cannot be scanned because it is
covered by structure, no HFEC inspection is required.
(f) For the borescope or video probe inspection of the forward 10 inches of the chord, it is necessary to attach
a dowel rod to the borescope or video probe if a flexible borescope or video probe is used. A sleeve (tube)
for the flexible borescope or video probe can be used instead of a dowel rod to make the flexible borescope
or video probe rigid.
(g) A 90 degree pencil probe with a minimum shaft length of 8 inches is required to reach the forward most
inspection area on the chord. Alternatively, a shorter 90 degree probe can be used with a dowel rod at-
tached to the handle. A shorter 90 degree probe can be used for the remaining inspection areas.
FIGURE 2: VERTICAL STABILIZER - RIGHT SIDE FIN CLOSURE RIB CHORD INSPECTION
(SHEET 2 OF 2)
Export Controlled ECCN: 9E991 - BOEING
PROPRIETARY - Copyright © Unpublished
Work - See page 1 for details.
Original Issue: September 24, 2012
727-55-0095
27 of 27
BOEING SERVICE BULLETIN 727-55-0095

---
OpenAirDocs.org is an independent research project of [Contrail Labs](https://contraillabs.com/). It is not affiliated with the FAA or the NTSB. Source documents are U.S. government works in the public domain, except the copies of manufacturers’ service documents, which belong to their rights holders.