# Boeing Special Attention Service Bulletin MD11-55-027: No revision named

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- Document: [Boeing Special Attention Service Bulletin MD11-55-027](https://openairdocs.org/service-documents/boeing/md11-55-027.md)
- Title as filed: U.S. DOT/FAA - Service Bulletin
- Pages: 18
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### Page 1

Commercial 
Airplanes
MD11
Service Bulletin
SPECIAL ATTENTION
Number: MD11-55-027
Original Issue: March 17, 2011
ATA System: 5510
SUBJECT: STABILIZERS - Horizontal Stabilizer - Change Rub Strips of Tail Fuel Tank Center
Box Front Spar Access Doors
Export of this technology is controlled under the United States Export Administration Regulations (EAR) (15
CFR 730-774). 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 © 2011 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Unpublished Work - All Rights Reserved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, 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 the
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connection with this document unless provided in writing by Boeing.
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Table of Contents
Summary ...................................................... 5
1. PLANNING INFORMATION ........................................ 7
A. Effectivity ................................................ 7
1. Airplanes ............................................. 7
2. Spares Affected ......................................... 7
B. Concurrent Requirements ....................................... 7
C. Reason ................................................. 8
D. Description ............................................... 8
E. Compliance .............................................. 8
F. Approval ................................................ 8
G. Manpower ............................................... 8
H. Weight and Balance Changes .................................... 9
I. Electrical Load Data .......................................... 9
J. References .............................................. 9
1. Existing Data .......................................... 9
2. Data supplied with this Service Bulletin ............................ 9
3. Installation Drawings Used in the Preparation of this Service Bulletin ............ 9
K. Publications Affected ........................................ 1 0
L. Interchangeability and Intermixability of Parts ........................... 1 0
2. MATERIAL INFORMATION ........................................ 1 1
A. Material - Price and Availability ................................... 1 1
B. Industry Support Information .................................... 1 1
C. Parts Necessary For Each Airplane ................................. 1 1
1. Kits/Parts ............................................ 1 1
2. Parts and Materials Supplied by the Operator ........................ 1 2
3. Parts Modified and Reidentified ................................ 1 2
4. Parts Removed and Not Replaced .............................. 1 2
D. Parts Necessary to Change Spares ................................. 1 2
E. Special Tooling - Price and Availability ............................... 1 2
F. Special Tooling Necessary to do this Service Bulletin ....................... 1 2
3. ACCOMPLISHMENT INSTRUCTIONS .................................. 1 3
A. GENERAL INFORMATION ..................................... 1 3
B. WORK INSTRUCTIONS ....................................... 1 4
FIGURE 1: CHANGE RUB STRIPS OF TAIL FUEL TANK CENTER BOX FRONT SPAR ACCESS DOOR
.................................................. 1 5
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Commercial 
Airplanes
MD11
Service Bulletin
SPECIAL ATTENTION
SummaryNumber: MD11-55-027Original Issue: March 17, 2011
ATA System: 5510
SUBJECT: STABILIZERS - Horizontal Stabilizer - Change Rub Strips of Tail Fuel Tank Center
Box Front Spar Access Doors
BOEING RECOMMENDS THAT EACH OPERATOR EXAMINE THIS SERVICE BULLETIN IMMEDIATELY.
CONCURRENT REQUIREMENTS
None.
BACKGROUND
An investigation by Boeing revealed that the rub strips of tail fuel tank center box front spar access doors were
manufactured improperly. Tail center box fuel tank front spar access door rub strips were inadvertently anodized
(electrically non-conductive) instead of alodined (electrically conductive) as prescribed in design drawings.
Anodization of the rub strips may prevent adequate electrical bonding between the rub strips and the doors.
Replacing anodized rub strips with alodined rub strips will provide adequate electrical bonding between the rub
strips and the fuel access doors. If not corrected, inadequate electrical bonding can contribute to possible ignition
of flammable fuel vapor in the tail fuel tank as a result of a lightning strike.
ACTION
This service bulletin provides instructions to change the rub strips of the tail fuel tank center box front spar access
doors.
EFFECTIVITY
MD-11 and MD-11F Airplanes. Refer to Paragraph 1.A.1., Airplanes, for the list of affected airplanes.
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.
Boeing recommends that the rub strips of the tail fuel tank center box front spar access doors be changed within
60 months after the original issue date on this service bulletin.
INDUSTRY SUPPORT INFORMATION
Boeing warranty remedies are available for airplanes in warranty as of July 21, 2010. Please refer to Paragraph
2.B., Industry Support Information.
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MANPOWER
Elapsed HoursTotal Task HoursAirplanes
16.032.0MD-11, MD-11F
MATERIAL INFORMATION
Boeing Supplied Kits/Parts.
Refer to Paragraph 2.A., Material - Price and Availability.
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Commercial 
Airplanes
MD11
Service Bulletin
SPECIAL ATTENTION
Number: MD11-55-027
Original Issue: March 17, 2011
ATA System: 5510
SUBJECT: STABILIZERS - Horizontal Stabilizer - Change Rub Strips of Tail Fuel Tank Center
Box Front Spar Access Doors
BOEING RECOMMENDS THAT EACH OPERATOR EXAMINE THIS SERVICE BULLETIN IMMEDIATELY.
1.    PLANNING INFORMATION
A. Effectivity
1. Airplanes
This service bulletin is for the airplanes shown below.
DESCRIPTIONCONFIGURATIONGROUP
Change Rub Strips of Tail Fuel Tank Center Box Front Spar Access
Doors for Fuselage Number 447 - 613
-1
Airplane Models:
MD-11, MD-11F
GroupFuselage Num-
ber
1447 - 613
2. Spares Affected
None.
B. Concurrent Requirements
None.
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C. Reason
An investigation by Boeing revealed that the rub strips of tail fuel tank center box front spar access
doors were manufactured improperly. Tail center box fuel tank front spar access door rub strips were
inadvertently anodized (electrically non-conductive) instead of alodined (electrically conductive) as
prescribed in design drawings. Anodization of the rub strips may prevent adequate electrical bonding
between the rub strips and the doors. Replacing anodized rub strips with alodined rub strips will provide
adequate electrical bonding between the rub strips and the fuel access doors. If not corrected, inadequate
electrical bonding can contribute to possible ignition of flammable fuel vapor in the tail fuel tank as a
result of a lightning strike.
D. Description
This service bulletin provides instructions to change the rub strips of the tail fuel tank center box front
spar access doors.
The work in this service bulletin is done in the maintenance zone(s) given below.
Affected Maintenance Zones
ZoneModel
189MD-11, MD-11F
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.
Boeing recommends that the rub strips of the tail fuel tank center box front spar access doors be
changed within 60 months after the original issue date on this service bulletin.
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 change 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:
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 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
5.010.02Defuel and Purge
1.02.02Remove Fuel Tank
Access Doors
7.515.02Change Rub Strips
1.02.02Install Fuel Tank Ac-
cess Doors
1.53.02Leak Check
16.032.0TOTAL FOR EACH AIRPLANE
H. Weight and Balance Changes
None.
I. Electrical Load Data
Not changed.
J. References
1. Existing Data
a. MD-11, MD-11F Aircraft Maintenance Manual (AMM) 52-57-19.
b. MD-11, MD-11F Structural Repair Manual (SRM) 51-42-07.
2. Data supplied with this Service Bulletin
None.
3. Installation Drawings Used in the Preparation of this Service Bulletin
ChangeTitleDocument Number
Z, AEO AASPAR ASSY - CONSTANT HORIZ
STAB, FORWARD
ALC8020
This drawing was used to prepare this service bulletin. This drawing is not necessary to make the
specified changes, and is not supplied with this service bulletin. This drawing may not be applicable
to all airplane configurations or operators.
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K. Publications Affected
1. Publications:
Chapter-SectionPublication
51-42-07Structural Repair Manual
2. Damage Tolerance Based Structural Inspections:
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 does not affect FCS, therefore DTIs are not necessary.
L. Interchangeability and Intermixability of Parts
Refer to Paragraph 2.C., Parts Necessary for Each Airplane, for interchangeability and intermixability
information.
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2.    MATERIAL INFORMATION
A. Material - Price and Availability
Boeing can supply the 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 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
ROLT as of the original
issue date of this Service
Bulletin (Calendar Days)
QTYNamePart Number
602RUB STRIPALC8028-1
6036RIVETBACR15BA3AD8C
B. Industry Support Information
Boeing warranty remedies are available for MD-11 airplanes in warranty as of July 21, 2010. For task
hour reimbursement for airplanes in warranty as of that date, send a warranty claim to Boeing
Commercial Airplanes Group - Warranties. The parts for airplanes in warranty as of that date will be
supplied at no charge. Send a purchase order for the parts to Boeing Spares. Please refer to this
service bulletin number and reference the airplane fuselage number in your purchase order.
Boeing Commercial Airplanes Group - Warranties
P.O. Box 3707
M/C 2L-46
Seattle, Washington 98124-2207 USA
(Service Bulletin MD11-55-027)
C. Parts Necessary For Each Airplane
1. Kits/Parts
To get the parts shown below, refer to Paragraph 2.A., Material - Price and Availability.
NOTE: The parts shown below and the items shown in Paragraph 2.C.2., Parts and Materials
Supplied by the Operator, are necessary for each airplane.
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NotesExisting PartNameQTYNew Part Number
(a)ALC8028-1RUB STRIP2ALC8028-1
(b)MS20426AD3RIVET36BACR15BA3AD8C
(a) Alodined rub strip, part number ALC8028-1 replaces existing anodized
rub strip part number ALC8028-1.
(b) Alodined rivet, part number BACR15BA3AD8C replaces existing rivet,
part number MS20426AD3.
2. Parts and Materials Supplied by the Operator
NotesNameQTYPart Number /
Specification
(a)Sealing Compound, Integral Fuel
Tanks and Fuel Cell Cavities
1 QuartPR-1422 B-2
(DMS 2082 B-2)
or
Equivalent
CAGEPRC-DeSoto International, Incorporation(a) Can be purchased from:
8357424811 Avenue Rockefeller
Valencia, California 91355-3468
3. Parts Modified and Reidentified
None.
4. Parts Removed and Not Replaced
None.
D. Parts Necessary to Change Spares
None.
E. Special Tooling - Price and Availability
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.
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3.    ACCOMPLISHMENT INSTRUCTIONS
A. GENERAL INFORMATION
WARNING: WHILE YOU DO WORK IN THE TAILCONE AREA, MAKE SURE THAT YOU OBEY
ALL SAFETY PRECAUTIONS. IF YOU DO NOT OBEY THE PRECAUTIONS, DEATH
OR INJURY TO PERSONS CAN OCCUR.
WARNING: IF ELECTRICAL POWER IS APPLIED TO THE AIRPLANE, MAKE SURE YOU OBEY
ALL PRECAUTIONS WHILE YOU DO WORK. IF YOU DO NOT OBEY THE
PRECAUTIONS, DEATH OR INJURY TO PERSONS, AND DAMAGE TO THE AIRPLANE
CAN OCCUR.
CAUTION: ELECTRICALLY GROUND THE AIRPLANE. THIS WILL HELP TO PREVENT DAMAGE
TO THE AIRPLANE OR EQUIPMENT.
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. The instructions identified in Paragraph 3.B., Work Instructions, and the Figure(s)
give the recommended sequence of steps. The sequence of steps to do this service
bulletin can be changed.
2. Manual titles are referred to by acronyms. Refer to Paragraph 1.J., References, for
definition of the acronyms.
3. Equivalent parts are listed in the AEPL, Drawing 7595071.
4. Use the approved fastener and process material substitutions, in accordance with
Structural Repair Manual MD-11, MD11F SRM 51.
5. If the length of any fastener specified in this service bulletin does not meet installation
standards given in MD-11, MD-11F SRM 51, then a fastener of the same specification,
or an approved substitute, with a length which meets the installation standards given
in MD-11, MD-11F SRM 51 may be used. In addition, washers may be installed for
fastener grip length in accordance with MD-11, MD-11F SRM 51.
6. A 1/8-inch thick stack of the same type washers called for in this service bulletin is
the maximum thickness which may be used under fastener head or nut to counteract
accumulation of tolerances.
EXCEPTION: When the available fastener length increments are greater than
1/16-inch, a 3/16-inch thick stack of the same type washers may be used.
7. Unless shown differently, these dimensions and tolerances are used:
– Linear dimensions are in inches
– Tolerance on linear dimensions, other than rivet and bolt edge margins, is plus
or minus 0.03 inch
– Tolerance on rivet and bolt edge margin is plus or minus 0.05 inch
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– Angular tolerance is plus or minus 2 degrees
– Hole dimensions for standard solid rivets are in Structural Repair Manual MD-11,
MD-11F SRM 51
– Torque limits to tighten nuts and bolts are in MD-11, MD-11F SRM 51.
8. These work instructions refer to procedures included in other Boeing documents.
When the words "refer to" are used and the operator has an accepted alternative
procedure, the accepted alternative procedure can be used. When the words "in
accordance with" are included in the instruction, the procedure in the Boeing document
must be used.
9. Where the work instructions include installation of a kept part, a new or serviceable
part with the same part number can be installed as an alternative to the kept part.
The removed part can be discarded if a new or serviceable part is installed.
10. 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.
B. WORK INSTRUCTIONS
1. Remove and keep tail fuel tank center box front spar access doors 352AZ and 352BZ. Refer to
MD-11, MD-11F AMM 52-57-19 as an accepted procedure.
2. Change rub strips in accordance with Figure 1 and MD-11, MD-11F SRM 51-42-07.
NOTE: Proper installation of the rub strips prevents fuel leaks and sparking during a lightning
strike to the airplane.
3. Install kept tail fuel tank center box front spar access doors 352AZ and 352BZ. Refer to MD-11,
MD-11F AMM 52-57-19 as an accepted procedure.
4. Put the airplane back to a serviceable condition.
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### Page 15 (OCR)

BOEING SERVICE BULLETIN MD11-55-027
GANG CHANNEL 12
-tot f.
(18 LOCATIONS) 12  RIVET
SPAR WEB
2) RUB STRIP
2 LOCATIONS  2019688
FIGURE 1: CHANGE RUB STRIPS OF TAIL FUEL TANK CENTER BOX FRONT SPAR ACCESS DOOR
(SHEET 1 OF 4)
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FIGURE 1: CHANGE RUB STRIPS OF TAIL FUEL TANK CENTER BOX FRONT SPAR ACCESS DOOR
(SHEET 2 OF 4)
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BOEING SERVICE BULLETIN MD11-55-027
GANG CHANNEL
RIVET
SPAR WEB
SPAR WEB
DOUBLER
• CURRENT FLOW
RUB STRIP
SEALANT
ACCESS DOOR
DOOR SEAL
FOR SHIPS 447 THROUGH 551
C-C
GANG CHANNEL-  RIVET
SPAR WEB
RUB STRIP  CURRENT FLOW
SEALANT
→--
ACCESS DOOR  DOOR SEAL
FOR SHIPS 552 THROUGH 613
C-C  2036134
FIGURE 1: CHANGE RUB STRIPS OF TAIL FUEL TANK CENTER BOX FRONT SPAR ACCESS DOOR
(SHEET 3 OF 4)
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### Page 18

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 the figure.
MORE DATAQTYIDENTIFICA-
TION
NAMETASKSTEP
(a)36MS20426AD3RivetRemove (Dis-
card)
1
2ALC8028-1Rub StripRemove (Dis-
card)
23D0292-1Gang ChannelRemove (Keep)
-PR-1422 B-2SealantRemove (Dis-
card) (DMS 2082 B-2)
-PR-1422 B-2SealantApply (New)2
(DMS 2082 B-2)
2ALC8028-1Rub StripInstall (New)
2ALC8028-1Rub StripDrill
23D0292-1Gang ChannelInstall (Kept)
36BACR15BA3AD8CRivetInstall (New)
(a) In accordance with MD-11, MD-11F SRM 51-42-07.
FIGURE 1: CHANGE RUB STRIPS OF TAIL FUEL TANK CENTER BOX FRONT SPAR ACCESS DOOR
(SHEET 4 OF 4)
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