PUBLISHED BY BOEING COMMERCIAL AIRPLANES GROUP, SEATTLE, WASHINGTON, USA 

• A DIVISION OF THE BOEING COMPANY •

DECLARATION STATEMENT 

 

To: All holders of this Boeing Document 

This document has EAR data with Export Control Classification Numbers (ECCN) of: 

9E991 

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. 

Effective 12/31/2009 references to MDC, DAC, MCDONNELL DOUGLAS or the 

DOUGLAS AIRCRAFT COMPANY contained in the content, header or footer refer to 

The Boeing Company. 

BOEING PROPRIETARY, CONFIDENTIAL, AND/OR TRADE SECRET 

Copyright © 2013 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Unpublished Work - All Rights Reserved 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 

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.
Report Number: MDC-02K1 003 

TRIJET SPECIAL COMPLIANCE ITEM REPORT 

Revision date: 02/0112013 Revision letter: K 

Issue date: 5/17/2002 Contract number: 

Prepared by: ~ A (! « --~ M:A:COX, Safety Engineering 

Commercial Aviation Services, Long Beach Division 

Approved by: -----'=~=---_ ... _· _· -~~_-.Jr-~ ___ .... _J_....o..e __ -___ _ S.J. Jinadasa, DC-10/MD-11 Chief Design Engineer 

OOP Design Office, Long Beach Division 

This report is FAA approved and specifies Special Compliance Items (SC!s) as required by Part 25.1529 of the Federal Aviation Regulations, and 

SFAR 88 Airworthiness Limitation Instructions (AL!s) & Critical Design Configuration Control Limitations (CDCCLs) required by Parts 25.981, 

25.!529 and 26.33 of the Federal Aviation Regulations, unless an alternative program has been approved by FAA Engineering of the Los Angeles 

Aircraft Certification Office (LA·ACO). This revision of the SCI report was approved by the Manager, Los Angeles Certification Office, 

Transport Airplane Directorate, on 5 ·Ol- 13 . Changes to this report must be approved by the LA·ACO. 

This document has EAR data with Export Control Classification Numbers (ECCN) of: 9E991 

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. 

BOEING PROPRIETARY, CONFIDENTIAL, AND/OR TRADE SECRET 

Copyright© 2013 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 infonnation, contact The Boeing Compmty, P.O. Box 3707, 

Seattle, Washington 98124. 

Boeing, the Boeing signature, the Boeing symbol, 707, 717, 727, 737, 747, 757, 767, 777, 787, BBJ, DC-8, DC-9, DC-10, MD-10, MD-11, MD80, 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 v.Titing by Boeing. 
U.S. Department 

of Transportation 

Federal Aviation 

Administration 

May I, 2013 

In reply refer to: 120L-13-171 

The Boeing Company 

ATTN.: Mr. Robert Beaudreau, 

Senior Manager, Certification & Airworthiness 

2401 E. Wardlow Rd., M/C DS00-0018 

Long Beach, CA 90807-5309 

R~c~'"~o 

\'\fl.~ (\ 3 '1.\)\3 

j\\R\\IOR'ffi~'i>S ct.RTI.HCi\.1\0~ & 

Reference: Boeing letter CP-L4L-13-00052, dated March 6, 2013 with FAA Forms 

8100-9 and Boeing Report MDC-02KI003, Revision K, dated February I, 

2013 (Enclosure B) 

Dear Mr. Beaudreau: 

Subject: Boeing Request for Approval of Revision K to Boeing Report No. 

MDC-02KI003, 'Trijet Special Compliance Item Report" 

The Federal Aviation Administration (FAA) has received the referenced letter requesting 

approval of Revision K to Boeing Report No. MDC-02KI003, 'Trijet Special Compliance 

Item Report." This request is applicable to McDonnell Douglas Models MD-II series, MDI 0 series and DC-I 0 series airplanes. 

The report contains additional maintenance requirements for design critical items identified 

as special compliance items (SCis ), and serves as a notification to operators and authorities 

of these SCis. The SCis are equivalent to one-star CMRs. The tasks and intervals defined 

in the SCis are mandatory and carmot be changed without approval from the cognizant FAA 

office. 

Revision K to this report added SCI 34-4, functional test of the captain and first officer's 

altimeter, and revised the airplane maintenance manual reference for the MD-II landing 

gears. 

We have reviewed the document and approve Revision K to Boeing Report MDC-02KI003. 
Should you have any questions regarding this approval, please contact this office or 

Ms. Nenita Odesa at telephone number (562) 627-5234, FAX (562) 627-5210, or electronic 

mail at nenita.odesa@faa.gov. 

Sincerely, 

~11- J'~.r Kevin Hull 

Manager, Los Angeles Aircraft Certification Office 

cc: LGB-AEG (Buffington) 

ANM-IOOL (Bandley) 

2 
INDEX OF PAGE CHANGES 

MDC-02KI003 

Revision B 

REVISION PAGES AFFECTED REMARKS REVISED APPROVED 

LETTER REVISED ADDED DELETED BY BY 

New 

A Title page 

01 

B 

IV-VI 

A4-A9 

B2 

B21 

All 

Appendix 

B&C 

iii 

Initial release. M. 

McKelvey 

Revised title page signatures as a result of M. 

SF AR88 activities. McKelvey 

AIO 

Added CDCCL's and ALI's m 

Appendices B and C, respectively, as a 

result of SF AR88 activity. 

Revised page number and applicability in 

Appendix D to include ALI's as well as 

SCI's. 

Added additional Index of Change Pages, 

to accommodate changed information for 

revision B. 

Revised Table of Contents to delete SCI 

number, title and interval summary for 

page A I 0; otherwise, the other pages 

incremented their page numbers due to 

new Index of Changed Pages sheet. 

Revised inspection interval and procedure 

of SCI's 34-1 thru 34-3 to be consistent 

with AD 2006-02-11. 

Deleted SCI 33-1 , as issuance of service 

bulletin MD 11-33-075 constitutes tenninating action to AD 2000-26-15 (this AD 

required inspection and repair as 

documented m SCI 33-1 and service 

bulletin MD II-33A069). 

Revised CDCCL implementation intent 

from an Operator's maintenance program 

to their control documents. This ensures 

that an Operator's Engineering department has visibility of control limitation 

information. 

Revised Limitation of CDCCL to include 

configuration information for DPS red 

wrap tape. 

BOEING PROPRIETARY INFORMATION 

Copyright © - The Boeing Company- Unpublished Work 

M. 

McKelvey 

12115/2005 

8/9/2006 

Page ii 
REVISION 

LETTER 

B 

c 

D 

INDEX OF PAGE CHANGES 

PAGES AFFECTED REMARKS 

REVISED ADDED DELETED 

B25-B26 

B33 

B39 

B40 

C6-C7 

V- Vl 

B24 

B25 - B42 

B38 

B40 

lV 

A4-A10 

Added a new, improved "-4" Hydro-Aire 

fuel pump to the CDCCL; this 

additionally caused a CMM revision. 

Revised fuel pump CMM (PIN 568-1-

27202-002) to include SF AR88 specific 

warning on Cover Page only and 

improved assembly quality checks. 

Revised Densitometer CMM to include 

SF AR88 specific warnings. 

Revised MJP CMM to include: 

• Six new, enhanced MJP PIN's (003-

008-208 thru -213) per Service 

Letter MD-11-SL-28-107-A, dated 

2/10/2006 

• Change the CMM revision level; 

this latest revision includes specific 

SF AR88 warnings. 

Added new ALI to inspect MD-11 Tail 

Tank FQGS wiring (both the metallic 

overbraid and the DMS 2186 red wrap 

tape). 

Deleted SCis 34-1 thru 34-3 and added 

CDCCL 20-15 to Table of Contents. 

Deleted SCis 34-1 thru 34-3 since AD 

2006-02-11 contains all necessary 

information. 

Added CDCCL 20-15 for float and 

pressure switch circuit fuse sleeves, part 

ofBDCO Project LB06-0039. 

All pages have been incremented to 

accommodate inclusion of new CDCCL 

20-15. 

Added 217-003-132 and 217-003-132M 

to CMM 28-41-25 at Rev 1. These part 

numbers were inadvertently left off in 

Supplier CMM data lists, and was added 

when the CMM itself was reviewed. 

Revised CMM 28-40-88 (part of CDCCL 

28-8) to include newly approved SEM 

part number and to roll the CMM revision 

level. 

BOEING PROPRIETARY INFORMATION 

Copyright©- The Boeing Company- Unpublished Work 

REVISED 

BY 

M. 

McKelvey 

M. 

McKelvey 

M.Cox 

11'/11-' 

6/fl"'" 

MDC-02K1003 

Revision D 

APPROVED 

BY 

~ 

8/9/2006 

~ (II '').11b(,.. 

S. Jinadasa 

7fJJt{ oJ 

M. McKelvey 

Page iii 
INDEX OF PAGE CHANGES 

MDC-02K1003 

Revision E 

REVISION 1----.::..P.:..:A:...:::G;.::E:..=S....::.A.=F:...::F:...::E:...:C:..;:T:...::E:.=D:.....___---l 

LETTER REVISED ADDED DELETED 

REMARKS REVISED 

BY 

APPROVED 

BY 

E iv-v 

vi- viii 

Vl 

A4-A12 

Al3-A22 

A23-A32 

A33-A42 

A43-A52 

A53-A62 

A63-A72 

A73-A93 

A94-A95 

A96-A97 

B2 

B27 

Added new Index of Change pages for 

revision E. 

M Cox M. McKelvey 

Incremented Table of Contents pages to 

~ 

accommodate new Index of Change Page. 

Added SCis 27-1 thru 27-8, 32-1 and 32-

2 to Table of Contents. 

Added SCI 27-1 for DC-10 horizontal ptt1.fZ ")_ 

stabilizer lubrication procedure. ' 0; 

Added SCI 27-2 for MD-10 horizontal 

stabilizer lubrication procedure. 

Added SCI 27-3 for MD-11 horizontal 

stabilizer lubrication procedure. 

Added SCI 27-4 for DC-10 two chain 

horizontal stabilizer wear check. 

Added SCI 27-5 for DC-10 four chain 

horizontal stabilizer wear check. 

Added SCI 27-6 for MD-10 two chain 

horizontal stabilizer wear check. 

Added SCI 27-7 for MD-10 four chain 

horizontal stabilizer wear check. 

Added SCI 27-8 for MD-11 horizontal 

stabilizer wear check. 

Added SCI 32-1 for Trijet landing gear 

truck beam pivot bolt lubrication 

Added SCI 32-2 for Trijet landing gear 

truck beam pivot bolt inspection 

Revised second to last paragraph to 

clarify CDCCL configuration control 

information to applicable Operator's 

Maintenance documentation. 

In CDCCL 28-2, CMM 28-22-03 

changed to revision 8, to support Service 

Bulletin DC10-28A254R1 and MD11-

28Al34R1 release. Changed CMM 28-

22-01 revision level to support Service 

Bulletin DC10-28A259 and MD11-

28Al38. 

BOEING PROPRIETARY INFORMATION 

Copyright©- The Boeing Company- Unpublished Work 

M. Lasley 

J. Reynolds 

A. Macias 

Page iv 
REVISION 

LETTER 

E 

F 

G 

INDEX OF PAGE CHANGES 

PAGES AFFECTED REMARKS REVISED 

REVISED ADDED DELETED BY 

B31-B32 CDCCL 28-4 moved to Report MDC09Kl000. 

B36 

B37 

B38 

B40-B41 

B21 , C6,C7 

Bl6-Bl7 

B24 

B27 

A4, All, 

Al3, A21, 

A23-A26 

Bl7 

CDCCL 28-6 Changed CMM 28-20-02 

revision level; latest approved CMM. 

CDCCL 28-7 Changed CMM 28-41-01 to 

CMM 28-41-20; latest approved CMM. 

PIN contained in CMM 28-41-01 were 

moved to CMM 28-41-20. 

CDCCL 28-7 Changes CMMs revision 

levels of 28-41-20, 28-41-17, 28-41-24, 

and 28-41-25; latest approved CMMs. 

Revised CDCCL 28-8 to include latest 

revision levels to CMMs 28-40-87, 28-

40-88 28-40-86 and 28-41-63 . Added 

PIN 367-040-073 to CMM 28-40-88, it is 

controlled by the CMM and inadvertently 

left off. 

Revised CDCCL 20-12 and ALI 20-2. 

Replaced "red-wrap" tape with DMS 

2186 self adhering tape 

Added CFR 26.33 Statement 

Revised CDCCL 20-9 to include a new 

SIB for wire protections 

Added fuse as part of CDCCL 20-15 

Revised CMM revision level in CDCCL 

28-2 

See 

Previous 

Page 

M. Cox 

. , 

SCI 27-1, 27-2, 27-3 were updated to M. Cox 

include the use ofBMS 3-33 grease ,4/,f-e--

Revised SIB DCl0-28-262 to reflect 

revision 1 or later. 

BOEING PROPRIETARY INFORMATION 

Copyright©- The Boeing Company- Unpublished Work 

MDC-02K1003 

Revision G 

APPROVED 

BY 

See Previous 

Page 

M. McKelvey 

A. Macias 

M. McKelvey 

~ 

M. Lasley 

JA1R.J-. 

Pagev 
REVISION 

LETTER 

H 

I 

J 

K 

INDEX OF PAGE CHANGES 

PAGES AFFECTED REMARKS 

REVISED ADDED 

vi-viii ix 

B4, B12, 

B14, B18, 

B19, B21, 

C7 

viii 

A98 

B6-B7 

B23 

B29-B30 

B40 

viii-ix 

A94-A95 

A98-

A102 

DELETED 

Added new Index of page changes, table 

of contents are on new page numbers. 

Added new CDCCL and ALI to table of 

contents 

Revised CDCCL information referring to 

OEM data to further defme OEM data 

sources. 

ALI 20-2 Fail criteria was revised to add 

"Repair per SWPM 20-10-01" 

Revision Level Not Used 

Revised name of CDCCL 20-14 to reflect 

alternate parts, now includes all Trijets, 

and SCI 33-1 

SCI 33-1 re-instated to reference AML 

MD-10-AML-33-101. The AML 

contains instructions for repetitive 

inspection and terminating action to 

inspection. 

CDCCL 20-3 updated to include alternate 

part drawing. 

CDCCL 20-14 name changed from 

MD11/MD-10 to Trijet, updated CDCCL 

to include drawing reference for alternate 

parts. Clarification was added for MD-11 

conduits without sleeving. 

CMM 28-23-02 was revised to revision 

10. 

CMM 28-40-87 was revised to revision 5. 

Added SCI 34-4 

Revised MD-11 AMM reference from 

12-21-01 to 12-21 

Added SCI 34-4 Functional Test of the 

Captain and First Officer's Altimeter 

BOEING PROPRIETARY INFORMATION 

Copyright©· The Boeing Company- Unpublished Work 

REVISED 

BY 

M.Cox 

~ A 

Ali.~.-

<eli 

M.Cox 

)_ I 

,... ' 

JV~ 

M.Cox 

~~~-

MDC-02K1003 

Revision K 

APPROVED 

BY 

M. McKelvey 

B. Nozari 

T. Harris 

A. Macias 

M.McKelvey 

K. Balbas 

T. Harris 

A. Macias 

~ r--. 

J~ 

Page vi 
MDC-02K1003 

Revision E 

BOEING PROPRIETARY INFORMATION 

Copyright © - The Boeing Company - Unpublished Work 

Page vii

TRIJET SPECIAL COMPLIANCE ITEM REPORT

TABLE OF CONTENTS

PAGE No. TITLE INTERVAL SUMMARY

 At intervals, prior to, 

 but not to exceed: 

1 Discussion 

A1 Appendix A - SCIs 

A4 27-1 DC-10 Horizontal Stabilizer Actuator 1,800 flt hrs (effective 

Lubrication 10/1/2009) 

A13 27-2 MD-10 Horizontal Stabilizer Actuator 1,800 flt hrs (effective 

Lubrication 10/1/2009) 

A23 27-3 MD-11 Horizontal Stabilizer Actuator 1,800 flt hrs (effective 

Lubrication 10/1/2009) 

A33 27-4 DC-10 Horizontal Stabilizer Actuator 15,000 flt hrs (effective 

Wear Check (Aircraft with Two Drive 10/1/2009) 

Chains) 

A43 27-5 DC-10 Horizontal Stabilizer Actuator 15,000 flt hrs (effective 

Wear Check (Aircraft with Four Drive 10/1/2009) 

Chains) 

A52 27-6 MD-10 Horizontal Stabilizer Actuator 15,000 flt hrs (effective 

Wear Check (Aircraft with Two Drive 10/1/2009) 

Chains) 

A62 27-7 MD-10 Horizontal Stabilizer Actuator 15,000 flt hrs (effective 

Wear Check (Aircraft with Four Drive 10/1/2009) 

Chains) 

A72 27-8 MD-11 Horizontal Stabilizer Actuator 15,000 flt hrs (effective 

Wear Check 10/1/2009) 

A94 32-1 Trijet Main Landing Gear Truck Beam 

 Pivot Bolt Lubrication 

E 
MDC-02K1003 

Revision K 

BOEING PROPRIETARY INFORMATION 

Copyright © - The Boeing Company - Unpublished Work 

Page viii

TRIJET SPECIAL COMPLIANCE ITEM REPORT

TABLE OF CONTENTS

PAGE No. TITLE __________________________

A96 32-2 Trijet Main Landing Gear Truck Beam 

 Pivot Bolt Inspection 

A98 33-1 MD-10 Map Light Inspection and Terminating Action

A99 34-4 Functional Test of the Captain and First Officer’s Altimeter 

B1 Appendix B - CDCCLs 

B4 20-1 Trijet Repair Wire Gauges 

B5 20-2 Trijet FQIS Wire Isolation 

B6 20-3 Trijet Fuel Pump Conduit Sleeves 

B8 20-4 Trijet In-Tank Wire Splices 

B10 20-5 Trijet Repair Wire Types 

B12 20-6 Trijet Wire Installations 

B13 20-7 Trijet Prohibition of Power Feeder Splices in Areas Above Fuel Tanks 

B14 20-8 Trijet Fuel Tank Access Door Bonding 

B16 20-9 Trijet Wing Root Area Lightning Protection 

B18 20-10 Trijet Fuel Tank Structural Design 

B19 20-11 MD-11 Maintenance of Winglet Bonds 

B21 20-12 MD-11 Maintenance of Tail Tank FQIS Wiring Overbraid 

B22 20-13 Trijet Wiring Near Fuel Tanks and Fuel Pipes 

B23 20-14 Trijet Float Switch Conduit Sleeves 

B24 20-15 Trijet Float and Pressure Switch Circuit Fuse Sleeves 

B25 28-1 Trijet Prohibit Safety Wire, Lockwire, Safety Cable or Cotter Pins Inside Fuel 

 Tanks 

K 
MDC-02K1003 

Revision K 

BOEING PROPRIETARY INFORMATION 

Copyright © - The Boeing Company - Unpublished Work 

Page ix

TRIJET SPECIAL COMPLIANCE ITEM REPORT

TABLE OF CONTENTS

PAGE No. TITLE __________________________

 Appendix B – CDCCLs (cont’d) 

B26 28-2 Trijet Fuel Pump (Boost or Transfer) and Housing Assemblies 

B29 28-3 DC-10/MD-10 Fuel Pump (APU Start) and Housing Assemblies 

B31 28-4 KC-10, KDC-10 Fuel Pump Assembly 

B33 28-5 MD-11 Fuel Pump and Canister Assemblies 

B35 28-6 Trijet Fuel Pump (APU Start) Assembly 

B37 28-7 DC-10 Fuel Quantity Master Indicators 

B40 28-8 MD-11 Fuel Quantity Standard Electronic Module, Densitometer, 

 Multi-Junction Probe, and Ultrasonic Processor Drive Unit 

B42 28-9 MD-10 Fuel Quantity Processor Unit 

PAGE No. TITLE INTERVAL SUMMARY

 At intervals, prior to, 

 but not to exceed: 

C1 Appendix C - ALIs 

C4 20-1 Trijet Fuel Pump and Auxiliary On condition 

 Hydraulic Pump Circuit Breaker 

 Reset 

C6 20-2 MD-11 Inspection of Tail Tank 5 years (effective 

 FQGS Wiring Overbraid 8/2/2006) 

D1 Appendix D – Short-Term Extensions 

K 
MDC-02K1003 

Revision F 

BOEING PROPRIETARY INFORMATION 

Copyright © - The Boeing Company - Unpublished Work 

Page 1

DISCUSSION 

Certain systems in the trijet fleet (see below) have been analyzed and found to require fixedinterval checks or limitations, as follows: 

 Special Compliance Items (SCIs) - see Appendix A for their description and a listing of 

SCI’s 

 Critical Design Configuration Control Limitations (CDCCLs) - see Appendix B for their 

description and a listing of CDCCL’s resulting from SFAR88 activities 

 Airworthiness Limitation Instructions (ALIs) - see Appendix C for their description and a 

listing of ALIs resulting from SFAR88 activities 

This Special Compliance Items (SCI) Report is the Type Certificate Data Sheet (TCDS) 

referenced report, which contains and documents SCIs, CDCCLs and ALIs. 

14 CFR Part 26.33 Airworthiness Limitations

Applicable airplanes have been analyzed and found to meet the flammability requirements 

without any limitations. 

DC-10 Series

DC-10-10 

DC-10-40 

DC-10-30 

DC-10-30F 

DC-10-30F (KC-10A, KDC-10) 

DC-10-10F 

DC-10-40F 

DC-10-15 

MD-10 Series

MD-10-10F 

MD-10-30F 

MD-11 Series

MD-11 

MD-11F 

F 
MDC-02K1003 

Revision New 

BOEING PROPRIETARY INFORMATION 

Copyright © - The Boeing Company - Unpublished Work 

Page A1

Appendix A 

Special Compliance Items (SCIs) 

 
MDC-02K1003 

Revision New 

BOEING PROPRIETARY INFORMATION 

Copyright © - The Boeing Company - Unpublished Work 

Page A2

TRIJET SPECIAL COMPLIANCE ITEM REPORT 

Special Compliance Items (SCIs) are a means of notifying the FAA, operators, and others of 

critical design items that cannot be changed without violating the design intent, potentially 

making the airplane unsafe. For example, the SCI might require a repetitive check of pitot probe 

drains. 

The terms of the applicable trijet Type Certificate are only valid when the SCIs are performed 

within the time intervals specified. SCIs are equivalent to one-star CMR’s, per Advisory 

Circular (AC) 25-19: the tasks and intervals specified are mandatory and cannot be changed, 

escalated, or deleted without the approval of FAA Engineering within the Aircraft Certification 

Office having cognizance over the type design. 

Temporary deviations from the SCI intervals are permitted within the limitations of Appendix D. 

While each SCI is included in this report, it is required that each SCI also be included in an 

appropriate document where it will be visible to airline personnel; therefore each SCI must be 

included in each Operator's Maintenance Program. 

The SCIs herein are in addition to the maintenance requirements established by the Maintenance 

Review Board activity and documented in the Maintenance Review Board Report. Inclusion of 

SCIs herein is only intended to limit the extension of task intervals for those portions of trijet 

systems identified. 
MDC-02K1003 

Revision New 

BOEING PROPRIETARY INFORMATION 

Copyright © - The Boeing Company - Unpublished Work 

Page A3

Each SCI specified herein includes the name of the system in which the SCI is needed, and the 

following information: 

1. What trijet model does this SCI apply to? 

2. What part or LRU is being checked? 

3. What failure mode is being looked for? 

4. How is it found? 

5. What tasks are to be performed? 

6. Is test equipment needed? 

7. What is the pass-fail criteria? 

8. What is the SCI interval? 

Each Pass-Fail criteria entry identifies each SCI task as an Inspection or Check, using the MRB 

definitions. 

Please report any negative inspection results to your local Boeing Field Service Representative. 

If the Boeing Field Service Representative is not available, you may send the report to: 

The Boeing Company 

3855 Lakewood Blvd. 

Long Beach, CA, USA 90846 

Attn: 

Manager - Avionics & Electrical Systems (Dept. L33) 

Service Engineering 

Technical Services & Modifications 

Mail Code: D800-0035 
MDC-02K1003 

Revision G 

BOEING PROPRIETARY INFORMATION 

Copyright © - The Boeing Company - Unpublished Work 

Page A4

SCI 27-1 - DC-10 HORIZONTAL STABILIZER ACTUATOR LUBRICATION 

1. What model does this SCI apply to?

DC-10 series aircraft 

2. What part or LRU is being checked?

Horizontal stabilizer actuator 

3. What failure mode is being looked for?

A check for a failure mode does not apply. This SCI provides a lubrication procedure for 

the horizontal stabilizer actuator. 

4. How is it found?

Not applicable 

5. What tasks are to be performed?

Perform the following horizontal stabilizer actuator lubrication procedure: 

1. General 

A. The grease removal and lubrication procedures must be done together and in the 

sequence listed. 

B. The use of clean, dry rags instead of solvent to remove the grease from the acme screws 

and acme nuts is recommended to prevent solvent contamination in the acme nuts. 

C. When lubricating vented joints (grease can freely and visibly flow out), apply grease to 

the fittings until only new grease shows from the joints. 

D. Do not intermix different grease specifications or different grease brands within the same 

specification. 

E. When changing from one grease specification or brand to another, do the procedure 

“Change the Approved Grease Specification or Brand” in DC-10 AMM Chapter 12-00-

00, paragraph entitled “General Lubrication - Maintenance Practice.” 

F. Refer to DC-10 MM 12-21-00 for general lubrication instructions. 

G 
MDC-02K1003 

Revision E 

BOEING PROPRIETARY INFORMATION 

Copyright © - The Boeing Company - Unpublished Work 

Page A5

SCI 27-1 - DC-10 HORIZONTAL STABILIZER ACTUATOR LUBRICATION 

(cont’d) 

G. The left and right horizontal stabilizer actuators are located forward of the horizontal 

stabilizer constant section. 

H. Access to the horizontal stabilizer actuators is through access door 311AB, zone 311, in 

the lower aft fuselage compartment. 

2. Remove the used grease from the horizontal stabilizer actuators. 

A. Move the horizontal stabilizer to the full aircraft nose down (AND) position. 

WARNING: BEFORE PRESSURIZING HYDRAULIC SYSTEMS, MAKE 

CERTAIN THAT LANDING GEAR GROUND LOCKPINS ARE 

INSTALLED AND THAT APPLICABLE CONTROLS ARE IN 

CORRECT POSITION TO PREVENT INADVERTENT OPERATION 

OF LANDING GEAR AND FLIGHT CONTROL SYSTEMS. 

(1) Pressurize hydraulic systems 1 and 3 (Ref. DC-10 MM 29-00-00, Page 201). 

WARNING: BEFORE MOVING HORIZONTAL STABILIZER TRIM CONTROLS, 

MAKE CERTAIN THAT AREAS AROUND HORIZONTAL 

STABILIZER AND ELEVATORS ARE CLEAR OF PERSONNEL AND 

EQUIPMENT AND THAT UPPER TAIL CONE DOORS ARE 

CLOSED. 

(2) Using the horizontal stabilizer trim switches on either control wheel, move the 

stabilizer to the full AND position. 

(3) Shut off the hydraulic pressure source. 

(4) Make sure that all three hydraulic systems are depressurized (Ref. DC-10 MM 29-

00-00, Page 201). 

(5) Open and tag the following circuit breakers: 

WARNING: TAG AND SAFETY CIRCUIT BREAKERS. 

 Circuit Breaker Panel Location Panel Area

AUTO PITCH TRIM A Avionics DC BUS 1 

AUTO PITCH TRIM B Avionics DC BUS 3 

HOR STAB ALTN TRIM CONT Avionics DC BUS 3 

E 
MDC-02K1003 

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BOEING PROPRIETARY INFORMATION 

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Page A6

PRIMARY HORIZ STAB TRIM Upper Main DC BUS 2 

SCI 27-1 - DC-10 HORIZONTAL STABILIZER ACTUATOR LUBRICATION 

(cont’d) 

(6) Put a “DO NOT OPERATE” tag on the horizontal stabilizer trim handles on the 

control pedestal. 

B. Apply grease to the left and right acme nut grease fittings (Ref. Figure 1). 

C. Clean the exposed threads on the left and right acme screws above the acme nuts and the 

tops of the acme nuts with clean, dry rags to remove as much grease as possible. 

D. Move the horizontal stabilizer to the full aircraft nose up (ANU) position. 

(1) Remove the safety tag and close the following circuit breaker: 

 Circuit Breaker Panel Location Panel Area

PRIMARY HORIZ STAB TRIM Upper Main DC BUS 2 

WARNING: BEFORE PRESSURIZING HYDRAULIC SYSTEMS, MAKE 

CERTAIN THAT LANDING GEAR GROUND LOCKPINS ARE 

INSTALLED AND THAT APPLICABLE CONTROLS ARE IN 

CORRECT POSITION TO PREVENT INADVERTENT OPERATION 

OF LANDING GEAR AND FLIGHT CONTROL SYSTEMS. 

(2) Pressurize hydraulic systems 1 and 3 (Ref. DC-10 MM 29-00-00, Page 201). 

WARNING: BEFORE MOVING HORIZONTAL STABILIZER TRIM CONTROLS, 

MAKE CERTAIN THAT AREAS AROUND HORIZONTAL 

STABILIZER AND ELEVATORS ARE CLEAR OF PERSONNEL AND 

EQUIPMENT AND THAT UPPER TAIL CONE DOORS ARE 

CLOSED. 

(3) Using the horizontal stabilizer trim switches on either control wheel, move the 

stabilizer to the full ANU position. 

(4) Shut off the hydraulic pressure source. 

(5) Make sure that all three hydraulic systems are depressurized (Ref. DC-10 MM 29-

00-00, Page 201). 

E 
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Page A7

SCI 27-1 - DC-10 HORIZONTAL STABILIZER ACTUATOR LUBRICATION 

(cont’d) 

(6) Open and tag the following circuit breaker: 

WARNING: TAG AND SAFETY CIRCUIT BREAKER. 

 Circuit Breaker Panel Location Panel Area

PRIMARY HORIZ STAB TRIM Upper Main DC BUS 2 

E. Clean the exposed threads on the left and right acme screws below the acme nuts and the 

bottoms of the acme nuts with clean, dry rags to remove as much grease as possible. 

3. Lubricate the horizontal stabilizer actuators (Ref. Figure 1). 

A. Put a layer of grease around the complete circumference of the exposed threads on the 

left and right acme screws. Make sure that the grease is liberally applied to the threads, 

including the flanks and bottom of each thread valley. 

B. Move the horizontal stabilizer to the full AND position. 

(1) Remove the safety tag and close the following circuit breaker: 

 Circuit Breaker Panel Location Panel Area

PRIMARY HORIZ STAB TRIM Upper Main DC BUS 2 

WARNING: BEFORE PRESSURIZING HYDRAULIC SYSTEMS, MAKE 

CERTAIN THAT LANDING GEAR GROUND LOCKPINS ARE 

INSTALLED AND THAT APPLICABLE CONTROLS ARE IN 

CORRECT POSITION TO PREVENT INADVERTENT OPERATION 

OF LANDING GEAR AND FLIGHT CONTROL SYSTEMS. 

(2) Pressurize hydraulic systems 1 and 3 (Ref. DC-10 MM 29-00-00, Page 201). 

WARNING: BEFORE MOVING HORIZONTAL STABILIZER TRIM CONTROLS, 

MAKE CERTAIN THAT AREAS AROUND HORIZONTAL 

STABILIZER AND ELEVATORS ARE CLEAR OF PERSONNEL AND 

EQUIPMENT AND THAT UPPER TAIL CONE DOORS ARE 

CLOSED. 

(3) Using the horizontal stabilizer trim switches on either control wheel, move the 

stabilizer to the full AND position. 

(4) Shut off the hydraulic pressure source. 

SCI 27-1 - DC-10 HORIZONTAL STABILIZER ACTUATOR LUBRICATION 

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Page A8

(cont’d) 

(5) Make sure that all three hydraulic systems are depressurized (Ref. DC-10 MM 29-

00-00, Page 201). 

(6) Open and tag the following circuit breaker: 

WARNING: TAG AND SAFETY CIRCUIT BREAKER. 

 Circuit Breaker Panel Location Panel Area

PRIMARY HORIZ STAB TRIM Upper Main DC BUS 2 

C. Put a layer of grease around the complete circumference of the exposed threads on the 

left and right acme screws. Make sure grease is liberally applied to the threads, including 

the flanks and bottom of each thread valley. 

D. Apply grease to the left and right acme nut grease fittings. 

E. Apply grease to the left and right sprocket bearings. 

F. Move the horizontal stabilizer to distribute the grease equally in the actuator. 

(1) Remove the safety tag and close the following circuit breaker: 

 Circuit Breaker Panel Location Panel Area

PRIMARY HORIZ STAB TRIM Upper Main DC BUS 2 

WARNING: BEFORE PRESSURIZING HYDRAULIC SYSTEMS, MAKE 

CERTAIN THAT LANDING GEAR GROUND LOCKPINS ARE 

INSTALLED AND THAT APPLICABLE CONTROLS ARE IN 

CORRECT POSITION TO PREVENT INADVERTENT OPERATION 

OF LANDING GEAR AND FLIGHT CONTROL SYSTEMS. 

(2) Pressurize hydraulic systems 1 and 3 (Ref. DC-10 MM 29-00-00, Page 201). 

WARNING: BEFORE MOVING HORIZONTAL STABILIZER TRIM CONTROLS, 

MAKE CERTAIN THAT AREAS AROUND HORIZONTAL 

STABILIZER AND ELEVATORS ARE CLEAR OF PERSONNEL 

AND EQUIPMENT AND THAT UPPER TAIL CONE DOORS ARE 

CLOSED. 

(3) Using the horizontal stabilizer trim switches on either control wheel, move the 

horizontal stabilizer to the full ANU and then the full AND positions. 

SCI 27-1 - DC-10 HORIZONTAL STABILIZER ACTUATOR LUBRICATION 

(cont’d) 

E 
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Page A9

(4) Move the horizontal stabilizer to the zero (neutral) position. 

(5) Shut off the hydraulic pressure source. 

(6) Make sure that all three hydraulic systems are depressurized (Ref. DC-10 MM 29-

00-00, Page 201). 

(7) Open and tag the following circuit breaker: 

WARNING: TAG AND SAFETY CIRCUIT BREAKER. 

 Circuit Breaker Panel Location Panel Area

PRIMARY HORIZ STAB TRIM Upper Main DC BUS 2 

G. Remove the grease that is not necessary from the left and right actuators. Do not remove 

grease from the working surfaces. 

H. Clean the structural areas around the actuators. Remove any grease that is not necessary 

and any loose materials (sand, dirt, drill shavings, etc.) that could contaminate the 

actuators. 

I. Remove the safety tags and close the following circuit breakers: 

 Circuit Breaker Panel Location Panel Area

AUTO PITCH TRIM A Avionics DC BUS 1 

AUTO PITCH TRIM B Avionics DC BUS 3 

HOR STAB ALTN TRIM CONT Avionics DC BUS 3 

PRIMARY HORIZ STAB TRIM Upper Main DC BUS 2 

J. Remove the “DO NOT OPERATE” tag from the horizontal stabilizer trim handles on the 

control pedestal. 

E 
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Page A10

SCI 27-1 - DC-10 HORIZONTAL STABILIZER ACTUATOR LUBRICATION 

(cont’d) 

Figure 1 (Sheet 1) 

E 
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Page A11

SCI 27-1 - DC-10 HORIZONTAL STABILIZER ACTUATOR LUBRICATION 

(cont’d) 

ITEM 

NO. ITEM DESCRIPTION 

LUBE 

TYPE APPLICATION 

NUMBER 

OF 

FITTINGS 

OR AREAS 

 1 Acme screw ++ Brush 1 

 2 Acme nut ++ Gun 1 

 3 Sprocket bearing WTR Gun 2 

++ Grease - Special Purpose (Aeroshell 14) 

WTR Grease - Wide Temperature Range - MIL-PRF-81322 

NOTE: WTR or BMS 3-33 grease may be used as an alternative to Special Purpose (++) grease 

for items 1 and 2. BMS 3-33 grease may be used as an alternative to WTR grease for 

item 3. Obey the grease intermix and changing precautions in Paragraph 1, General. 

Figure 1 (Sheet 2)

G 
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Copyright © - The Boeing Company - Unpublished Work 

Page A12

SCI 27-1 - DC-10 HORIZONTAL STABILIZER ACTUATOR LUBRICATION 

(cont’d) 

6. Is test equipment needed?

No test equipment is required. 

7. What is pass/fail criteria?

This SCI provides a lubrication servicing procedure; pass/fail criteria do not apply. 

8. What is SCI interval?

The horizontal stabilizer actuator lubrication procedure shall be performed at intervals 

not to exceed 1,800 flight hours. 

E 
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Copyright © - The Boeing Company - Unpublished Work 

Page A13

SCI 27-2 - MD-10 HORIZONTAL STABILIZER ACTUATOR LUBRICATION 

1. What model does this SCI apply to?

MD-10 series aircraft 

2. What part or LRU is being checked?

Horizontal stabilizer actuator 

3. What failure mode is being looked for?

A check for a failure mode does not apply. This SCI provides a lubrication procedure for 

the horizontal stabilizer actuator. 

4. How is it found?

Not applicable 

5. What tasks are to be performed?

Perform the following horizontal stabilizer actuator lubrication procedure: 

1. General

 

A. The grease removal and lubrication procedures must be done together and in the 

sequence listed. 

B. The use of clean, dry rags instead of solvent to remove grease from the acme screws and 

nuts is recommended to prevent solvent contamination in the acme nuts. 

C. When lubricating vented joints (grease can freely and visibly flow out), apply grease to 

the fittings until only new grease shows from the joints. 

D. Do not intermix different grease specifications or different grease brands within the same 

specification. 

E. When changing from one grease specification or brand to another, do the procedure 

“Change the Approved Grease Specification or Brand” in MD-10 AMM Chapter 12-00-

00, paragraph entitled “General Lubrication – Maintenance Practices.” 

F. Refer to MD-10 AMM 12-21-00 for general lubrication instructions.

G 
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Page A14

SCI 27-2 - MD-10 HORIZONTAL STABILIZER ACTUATOR LUBRICATION 

(cont’d) 

G. The left and right horizontal stabilizer actuators are located forward of the horizontal 

stabilizer constant section. 

H. Access to the horizontal stabilizer actuators is through access door 311AB, zone 311, in 

the lower aft fuselage compartment. 

2. Remove Used Grease from Horizontal Stabilizer Actuators

A. Move the horizontal stabilizer to the full aircraft nose down (AND) position. 

WARNING: BEFORE PRESSURIZING HYDRAULIC SYSTEMS, MAKE 

CERTAIN THAT LANDING GEAR GROUND LOCKPINS ARE 

INSTALLED AND THAT APPLICABLE CONTROLS ARE IN 

CORRECT POSITION TO PREVENT INADVERTENT OPERATION 

OF LANDING GEAR AND FLIGHT CONTROL SYSTEMS. 

(1) Pressurize hydraulic systems 1 and 3 (MD-10 AMM, PAGEBLOCK 29-00-00/201). 

WARNING: BEFORE MOVING HORIZONTAL STABILIZER TRIM CONTROLS, 

MAKE CERTAIN THAT AREAS AROUND HORIZONTAL 

STABILIZER AND ELEVATORS ARE CLEAR OF PERSONNEL AND 

EQUIPMENT AND THAT UPPER TAIL CONE DOORS ARE 

CLOSED. 

(2) Using the horizontal stabilizer trim switches on either control wheel, move the 

stabilizer to the full AND position. 

(3) Shut off the hydraulic pressure source. 

(4) Make sure that all three hydraulic systems are depressurized (MD-10 AMM, 

PAGEBLOCK 29-00-00/201). 

E 
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Page A15

SCI 27-2 - MD-10 HORIZONTAL STABILIZER ACTUATOR LUBRICATION 

(cont’d) 

WARNING: TAG AND USE SAFETY CLIPS TO SAFETY THE CIRCUIT 

BREAKERS. IF THE CIRCUIT BREAKERS ARE NOT OPENED, 

TAGGED, AND SAFETIED, INJURY TO PERSONS AND DAMAGE 

TO EQUIPMENT CAN OCCUR. 

(5) Open these circuit breakers and install safety tags: 

AVIONICS, FLIGHT CONTROL DC BUS 1 

Row Col Number Name

C 8 B1-693 AUTO PITCH TRIM 1 

AVIONICS, MISC DC BUS 2 

Row Col Number Name

F 3 B1-507 PRIMARY HORIZ STAB TRIM 

OVERHEAD, RIGHT EMER DC BUS 

Row Col Number Name

E 26 B1-694 AUTO PITCH TRIM 2 

(6) Put a “DO NOT OPERATE” tag on the horizontal stabilizer trim handles on the 

control pedestal. 

B. Apply grease to the left and right acme nut grease fittings (Figure 1). 

C. Clean the exposed threads on the left and right acme screws above the acme nuts and the 

tops of the two acme nuts with clean, dry rags to remove as much grease as possible. 

D. Move the horizontal stabilizer to the full aircraft nose up (ANU) position. 

(1) Remove the safety tag and close this circuit breaker: 

AVIONICS, MISC DC BUS 2 

Row Col Number Name

F 3 B1-507 PRIMARY HORIZ STAB TRIM 

E 
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Revision E 

BOEING PROPRIETARY INFORMATION 

Copyright © - The Boeing Company - Unpublished Work 

Page A16

SCI 27-2 - MD-10 HORIZONTAL STABILIZER ACTUATOR LUBRICATION 

(cont’d) 

WARNING: BEFORE PRESSURIZING HYDRAULIC SYSTEMS, MAKE 

CERTAIN THAT LANDING GEAR GROUND LOCKPINS ARE 

INSTALLED AND THAT APPLICABLE CONTROLS ARE IN 

CORRECT POSITION TO PREVENT INADVERTENT OPERATION 

OF LANDING GEAR AND FLIGHT CONTROL SYSTEMS. 

(2) Pressurize hydraulic systems 1 and 3 (MD-10 AMM, PAGEBLOCK 29-00-00/201). 

WARNING: BEFORE MOVING HORIZONTAL STABILIZER TRIM CONTROLS, 

MAKE CERTAIN THAT AREAS AROUND HORIZONTAL 

STABILIZER AND ELEVATORS ARE CLEAR OF PERSONNEL AND 

EQUIPMENT AND THAT UPPER TAIL CONE DOORS ARE 

CLOSED. 

(3) Using the horizontal stabilizer trim switches on either control wheel, move the 

stabilizer to the full ANU position. 

(4) Shut off the hydraulic pressure source. 

(5) Make sure that all three hydraulic systems are depressurized (MD-10 AMM, 

PAGEBLOCK 29-00-00/201). 

WARNING: TAG AND USE A SAFETY CLIP TO SAFETY THE CIRCUIT 

BREAKER. IF THE CIRCUIT BREAKER IS NOT OPENED, 

TAGGED, AND SAFETIED, INJURY TO PERSONS AND DAMAGE 

TO EQUIPMENT CAN OCCUR. 

(6) Open this circuit breaker and install a safety tag: 

AVIONICS, MISC DC BUS 2 

Row Col Number Name

F 3 B1-507 PRIMARY HORIZ STAB TRIM 

E. Clean the exposed threads on the left and right acme screws below the acme nuts and the 

bottoms of the acme nuts with clean, dry rags to remove as much grease as possible. 

3. Lubricate Horizontal Stabilizer Actuators (Figure 1)

A. Put a layer of grease around the complete circumference of the exposed threads on the 

left and right acme screws. Make sure that the grease is liberally applied to the threads, 

including the flanks and bottom of each thread valley. 

E 
MDC-02K1003 

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Page A17

SCI 27-2 - MD-10 HORIZONTAL STABILIZER ACTUATOR LUBRICATION 

(cont’d) 

B. Move the horizontal stabilizer to the full AND position. 

(1) Remove the safety tag and close this circuit breaker: 

AVIONICS, MISC DC BUS 2 

Row Col Number Name

F 3 B1-507 PRIMARY HORIZ STAB TRIM 

WARNING: BEFORE PRESSURIZING HYDRAULIC SYSTEMS, MAKE 

CERTAIN THAT LANDING GEAR GROUND LOCKPINS ARE 

INSTALLED AND THAT APPLICABLE CONTROLS ARE IN 

CORRECT POSITION TO PREVENT INADVERTENT OPERATION 

OF LANDING GEAR AND FLIGHT CONTROL SYSTEMS. 

(2) Pressurize hydraulic systems 1 and 3 (MD-10 AMM, PAGEBLOCK 29-00-00/201). 

WARNING: BEFORE MOVING HORIZONTAL STABILIZER TRIM CONTROLS, 

MAKE CERTAIN THAT AREAS AROUND HORIZONTAL 

STABILIZER AND ELEVATORS ARE CLEAR OF PERSONNEL AND 

EQUIPMENT AND THAT UPPER TAIL CONE DOORS ARE 

CLOSED. 

(3) Using the horizontal stabilizer trim switches on either control wheel, move the 

stabilizer to the full AND position. 

(4) Shut off the hydraulic pressure source. 

(5) Make sure that all three hydraulic systems are depressurized (MD-10 AMM, 

PAGEBLOCK 29-00-00/201). 

WARNING: TAG AND USE A SAFETY CLIP TO SAFETY THE CIRCUIT 

BREAKER. IF THE CIRCUIT BREAKER IS NOT OPENED, 

TAGGED, AND SAFETIED, INJURY TO PERSONS AND DAMAGE 

TO EQUIPMENT CAN OCCUR. 

(6) Open this circuit breaker and install a safety tag: 

AVIONICS, MISC DC BUS 2 

Row Col Number Name

F 3 B1-507 PRIMARY HORIZ STAB TRIM 

E 
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Page A18

SCI 27-2 - MD-10 HORIZONTAL STABILIZER ACTUATOR LUBRICATION 

(cont’d) 

C. Put a layer of grease around the complete circumference of the exposed threads on the 

left and right acme screws. Make sure that the grease is liberally applied to the threads, 

including the flanks and bottom of each thread valley. 

D. Apply grease to the left and right acme nut grease fittings. 

E. Apply grease to the left and right sprocket bearings. 

F. Move the horizontal stabilizer to distribute the grease equally in the actuator. 

(1) Remove the safety tag and close this circuit breaker: 

AVIONICS, MISC DC BUS 2 

Row Col Number Name

F 3 B1-507 PRIMARY HORIZ STAB TRIM 

WARNING: BEFORE PRESSURIZING HYDRAULIC SYSTEMS, MAKE 

CERTAIN THAT LANDING GEAR GROUND LOCKPINS ARE 

INSTALLED AND THAT APPLICABLE CONTROLS ARE IN 

CORRECT POSITION TO PREVENT INADVERTENT OPERATION 

OF LANDING GEAR AND FLIGHT CONTROL SYSTEMS. 

(2) Pressurize hydraulic systems 1 and 3 (MD-10 AMM, PAGEBLOCK 29-00-00/201). 

WARNING: BEFORE MOVING HORIZONTAL STABILIZER TRIM CONTROLS, 

MAKE CERTAIN THAT AREAS AROUND HORIZONTAL 

STABILIZER AND ELEVATORS ARE CLEAR OF PERSONNEL AND 

EQUIPMENT AND THAT UPPER TAIL CONE DOORS ARE 

CLOSED. 

(3) Using the horizontal stabilizer trim switches on either control wheel, move the 

horizontal stabilizer to the full ANU and then the full AND positions. 

(4) Move the horizontal stabilizer to the zero (neutral) position. 

(5) Shut off the hydraulic pressure source. 

(6) Make sure that all three hydraulic systems are depressurized (MD-10 AMM, 

PAGEBLOCK 29-00-00/201). 

E 
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Copyright © - The Boeing Company - Unpublished Work 

Page A19

SCI 27-2 - MD-10 HORIZONTAL STABILIZER ACTUATOR LUBRICATION 

(cont’d) 

WARNING: TAG AND USE A SAFETY CLIP TO SAFETY THE CIRCUIT 

BREAKER. IF THE CIRCUIT BREAKER IS NOT OPENED, 

TAGGED, AND SAFETIED, INJURY TO PERSONS AND DAMAGE 

TO EQUIPMENT CAN OCCUR. 

(7) Open this circuit breaker and install a safety tag: 

AVIONICS, MISC DC BUS 2 

Row Col Number Name

F 3 B1-507 PRIMARY HORIZ STAB TRIM 

G. Remove the grease that is not necessary from the left and right actuators. Do not remove 

grease from the working surfaces. 

H. Clean the structural areas around the actuators. Remove any grease that is not necessary 

and any loose material (sand, dirt, drill shavings, etc.) that could contaminate the 

actuators. 

I. Remove the safety tags and close these circuit breakers: 

AVIONICS, FLIGHT CONTROL DC BUS 1 

Row Col Number Name

C 8 B1-693 AUTO PITCH TRIM 1 

AVIONICS, MISC DC BUS 2 

Row Col Number Name

F 3 B1-507 PRIMARY HORIZ STAB TRIM 

OVERHEAD, RIGHT EMER DC BUS 

Row Col Number Name

E 26 B1-694 AUTO PITCH TRIM 2 

J. Remove the “DO NOT OPERATE” tag from the horizontal stabilizer trim handles on the 

control pedestal. 

E 
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BOEING PROPRIETARY INFORMATION 

Copyright © - The Boeing Company - Unpublished Work 

Page A20

SCI 27-2 - MD-10 HORIZONTAL STABILIZER ACTUATOR LUBRICATION 

(cont’d) 

Figure 1 (Sheet 1) 

E 

CAG(IGDS) 

LUBRICATION 

PLACARD 

/ 

NOTE: 

LEFT SID 

RIGHT SI~~~~~ONSITE. 

ACCESS DOOR 

DC-10 LUB F1 
MDC-02K1003 

Revision G 

BOEING PROPRIETARY INFORMATION 

Copyright © - The Boeing Company - Unpublished Work 

Page A21

SCI 27-2 - MD-10 HORIZONTAL STABILIZER ACTUATOR LUBRICATION 

(cont’d) 

ITEM 

NO. 

ITEM 

DESCRIPTION 

LUBE 

TYPE APPLICATION 

NUMBER OF 

FITTINGS 

OR AREAS 

 1 Acme screw ++ Brush 1 

 2 Acme nut ++ Gun 1 

 3 Sprocket bearing WTR Gun 2 

++ Grease - Special Purpose (Aeroshell 14) 

WTR Grease - Wide Temperature Range - MIL-PRF-81322 

NOTE: WTR or BMS 3-33 grease may be used as an alternative to Special 

Purpose (++) grease for items 1 and 2. BMS 3-33 grease may be 

used as an alternative to WTR grease for item 3. Obey the grease 

intermix and changing precautions in Paragraph 1, General. 

Figure 1 (Sheet 2) 

G 
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BOEING PROPRIETARY INFORMATION 

Copyright © - The Boeing Company - Unpublished Work 

Page A22

SCI 27-2 - MD-10 HORIZONTAL STABILIZER ACTUATOR LUBRICATION 

(cont’d) 

6. Is test equipment needed?

No test equipment is required. 

7. What is pass/fail criteria?

This SCI provides a lubrication servicing procedure; pass/fail criteria do not apply. 

8. What is SCI interval?

The horizontal stabilizer actuator lubrication procedure shall be performed at intervals 

not to exceed 1,800 flight hours. 

E 
MDC-02K1003 

Revision G 

BOEING PROPRIETARY INFORMATION 

Copyright © - The Boeing Company - Unpublished Work 

Page A23

SCI 27-3 - MD-11 HORIZONTAL STABILIZER ACTUATOR LUBRICATION 

1. What model does this SCI apply to?

MD-11 series aircraft 

2. What part or LRU is being checked?

Horizontal stabilizer actuator 

3. What failure mode is being looked for?

A check for a failure mode does not apply. This SCI provides a lubrication procedure for 

the horizontal stabilizer actuator. 

4. How is it found?

Not applicable 

5. What tasks are to be performed?

Perform the following horizontal stabilizer actuator lubrication procedure: 

1. General

A. This procedure has the instructions for lubricating the horizontal stabilizer actuator. 

B. The grease removal and lubrication procedures must be done together and in the 

sequence listed. 

C. The use of clean, dry rags instead of solvent to remove grease from the acme screws and 

nuts is recommended to prevent solvent contamination in the acme nuts. 

D. When lubricating vented joints (grease can freely and visibly flow out), apply grease to 

the fittings until only new grease shows from the joints. 

E. Do not intermix different grease specifications or different grease brands in the same 

specification. 

F. When changing from one grease specification or brand to another, do the procedure in 

MD-11 AMM Chapter 12-00-00 (CHANGE THE APPROVED GREASE 

SPECIFICATION OR BRAND, TASK 12-00-00-617-801). 

G 
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Revision G 

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Page A24

SCI 27-3 - MD-11 HORIZONTAL STABILIZER ACTUATOR LUBRICATION 

(cont’d) 

G. The referenced TASK numbers apply to the MD-11 AMM. 

2. LUBRICATION OF THE HORIZONTAL STABILIZER ACTUATOR

A. Fixtures, Tools, Test and Support Equipment 

(1) Fixtures, Tools, Test and Support Equipment 

NOTE: Equivalent replacements are permitted for the items that follow. 

Table 1 

REFERENCE DESIGNATION 

Not specified Grease gun 

Not specified Brush 

Not specified Maintenance platform, 10-15 ft (3-5 m) high 

B. Consumable Materials 

(1) Consumable Materials 

NOTE: Equivalent replacements are permitted for the items that follow. 

NOTE: It is possible that some materials in the Consumable Materials chart 

cannot be used for some or all of their necessary applications. Before you 

use the materials, make sure the types, quantities, and applications of the 

materials necessary are legally permitted in your location. All persons 

must obey all applicable federal, state, local, and provincial laws and 

regulations when it is necessary to work with these materials. 

Table 2 

REFERENCE DESIGNATION 

MIL-PRF-81322 

(DPM 5348) 

Grease, wide temperature range (WTR) 

DPM 5850 Grease, special purpose, Aeroshell 14 (**) 

BMS 3-33 Grease, general purpose (GPG) G 
MDC-02K1003 

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Page A25

SCI 27-3 - MD-11 HORIZONTAL STABILIZER ACTUATOR LUBRICATION 

(cont’d) 

C. References 

Reference Title 

12-00-00-617-801 

27-40-00-860-801 

CHANGE THE APPROVED GREASE 

SPECIFICATION OR BRAND (MD-11 AMM, P/B 201) 

OPERATION OF THE HORIZONTAL STABILIZER 

(MD-11 AMM, P/B 201) 

D. Access Panel 

Number Name/Location 

311AB AFT FUSELAGE 

E. Job Set-up - Horizontal Stabilizer Actuator Lubrication 

(1) Open this access panel: 

Number Name/Location

311AB AFT FUSELAGE 

F. Procedure - Horizontal Stabilizer Actuator Lubrication 

WARNING: USE THE HAZARDOUS MATERIAL WARNINGS GIVEN BELOW 

FOR THE STEPS THAT FOLLOW. 

THE HAZARDOUS MATERIAL WARNINGS ARE LISTED AFTER 

THE INTRODUCTION SECTION IN THE FRONT OF THE MD-11 

AMM. 

Hazardous Material Warnings 

HAZMAT 1013, LUBRICANT/GREASE (DPM 5348/317/326) 

HAZMAT 1000, REFER TO MSDS 

HAZMAT 1741, BMS 3-33 

G 

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Page A26

SCI 27-3 - MD-11 HORIZONTAL STABILIZER ACTUATOR LUBRICATION 

(cont’d) 

NOTE: A number identifies the lubrication points. A lubrication symbol and a two or three 

letter key at each point shows the lubricant and equipment used. 

Table 3 

ITEM NO. ITEM DESCRIPTION LUBE TYPE APPLICATION 

NO. OF 

FITTINGS 

OR AREAS 

1 Acme screw ** 

(DPM 5850) 

Brush 1 

2 Acme nut ** 

(DPM 5850) 

Grease gun 1 

3 Sprocket bearing WTR 

(MIL-PRF81322) 

Grease gun 2 

NOTE: The number of fittings or areas is for one side only. The opposite side is the 

same. 

NOTE: WTR or BMS 3-33 grease may be used as an alternative to DPM 5850 (**) 

grease for items 1 and 2. BMS 3-33 grease may be used as an alternative to 

WTR grease for item 3. Obey the grease intermix and changing precautions in 

Paragraph 1, General. 

(1) Remove the used grease from the horizontal stabilizer actuators. (Figure 1) 

(a) Move the horizontal stabilizer to the full aircraft nose down (AND) position. 

(OPERATION OF THE HORIZONTAL STABILIZER, TASK 27-40-00-860-

801) 

WARNING: TAG AND USE SAFETY CLIPS TO SAFETY THE CIRCUIT 

BREAKERS. IF THE CIRCUIT BREAKERS ARE NOT 

OPENED, TAGGED, AND SAFETIED, INJURY TO PERSONS 

AND DAMAGE TO EQUIPMENT CAN OCCUR. 

(b) Open these circuit breakers and install safety tags: 

AVIONICS, FLIGHT CONTROL DC BUS 1 

Row Col Number Name

C 8 B1-693 AUTO PITCH TRIM 1 

G 
MDC-02K1003 

Revision E 

BOEING PROPRIETARY INFORMATION 

Copyright © - The Boeing Company - Unpublished Work 

Page A27

SCI 27-3 - MD-11 HORIZONTAL STABILIZER ACTUATOR LUBRICATION 

(cont’d) 

AVIONICS, MISC DC BUS 2 

Row Col Number Name

F 3 B1-507 PRIMARY HORIZ STAB TRIM 

OVERHEAD, RIGHT EMER DC BUS 

Row Col Number Name

E 26 B1-694 AUTO PITCH TRIM 2 

(c) Put a “DO NOT OPERATE” tag on the horizontal stabilizer suitcase handles 

on the control pedestal. 

(d) Apply grease to the grease fittings on the left and right acme nuts. 

(e) Clean the exposed threads on the left and right acme screws above the acme 

nuts and the tops of the two acme nuts with clean, dry rags to remove as much 

grease as possible. 

(f) Remove the safety tag and close this circuit breaker: 

AVIONICS, MISC DC BUS 2 

Row Col Number Name

F 3 B1-507 PRIMARY HORIZ STAB TRIM 

(g) Move the horizontal stabilizer to the full aircraft nose up (ANU) position. 

(OPERATION OF THE HORIZONTAL STABILIZER, TASK 27-40-00-860-

801) 

WARNING: TAG AND USE A SAFETY CLIP TO SAFETY THE CIRCUIT 

BREAKER. IF THE CIRCUIT BREAKER IS NOT OPENED, 

TAGGED, AND SAFETIED, INJURY TO PERSONS AND 

DAMAGE TO EQUIPMENT CAN OCCUR. 

(h) Open this circuit breaker and install a safety tag: 

AVIONICS, MISC DC BUS 2 

Row Col Number Name

F 3 B1-507 PRIMARY HORIZ STAB TRIM 

SCI 27-3 - MD-11 HORIZONTAL STABILIZER ACTUATOR LUBRICATION 

E 
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Page A28

(cont’d) 

(i) Clean the exposed threads on the left and right acme screws below the acme 

nuts and the bottoms of the two acme nuts with clean, dry rags to remove as 

much grease as possible. 

(2) Lubricate the horizontal stabilizer actuators. (Figure 1) 

(a) Put a layer of grease around the complete circumference of the exposed threads 

on the left and right acme screws. Make sure that the grease is liberally 

applied to the threads, including the flanks and bottom of each thread valley. 

(b) Remove the safety tag and close this circuit breaker: 

AVIONICS, MISC DC BUS 2 

Row Col Number Name

F 3 B1-507 PRIMARY HORIZ STAB TRIM 

(c) Move the horizontal stabilizer to the full AND position. (OPERATION OF 

THE HORIZONTAL STABILIZER, TASK 27-40-00-860-801) 

WARNING: TAG AND USE A SAFETY CLIP TO SAFETY THE CIRCUIT 

BREAKER. IF THE CIRCUIT BREAKER IS NOT OPENED, 

TAGGED, AND SAFETIED, INJURY TO PERSONS AND 

DAMAGE TO EQUIPMENT CAN OCCUR. 

(d) Open this circuit breaker and install a safety tag: 

AVIONICS, MISC DC BUS 2 

Row Col Number Name

F 3 B1-507 PRIMARY HORIZ STAB TRIM 

(e) Put a layer of grease around the complete circumference of the exposed threads 

on the two acme screws. Make sure that the grease is liberally applied to the 

threads, including the flanks and bottom of each thread valley. 

(f) Apply grease to the left and right acme nuts. 

(g) Apply grease to the left and right sprocket bearings. 

E 
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Revision E 

BOEING PROPRIETARY INFORMATION 

Copyright © - The Boeing Company - Unpublished Work 

Page A29

SCI 27-3 - MD-11 HORIZONTAL STABILIZER ACTUATOR LUBRICATION 

(cont’d) 

(h) Remove the safety tag and close this circuit breaker: 

AVIONICS, MISC DC BUS 2 

Row Col Number Name

F 3 B1-507 PRIMARY HORIZ STAB TRIM 

(i) Move the horizontal stabilizer to distribute the grease equally in the actuator. 

(OPERATION OF THE HORIZONTAL STABILIZER, TASK 27-40-00-860-

801) 

1) Move the horizontal stabilizer to the full ANU and then the full AND 

positions. 

2) Move the horizontal stabilizer to the zero (neutral) position. 

WARNING: TAG AND USE A SAFETY CLIP TO SAFETY THE CIRCUIT 

BREAKER. IF THE CIRCUIT BREAKER IS NOT OPENED, 

TAGGED, AND SAFETIED, INJURY TO PERSONS AND 

DAMAGE TO EQUIPMENT CAN OCCUR. 

(j) Open this circuit breaker and install a safety tag: 

AVIONICS, MISC DC BUS 2 

Row Col Number Name

F 3 B1-507 PRIMARY HORIZ STAB TRIM 

(k) Remove the grease that is not necessary from the left and right actuators. Do 

not remove grease from the working surfaces. 

(l) Clean the structural areas around the actuators. Remove any grease that is not 

necessary and any loose material (sand, dirt, drill shavings, etc.) that could 

contaminate the actuators. 

G. Job Close-up - Horizontal Stabilizer Actuator Lubrication 

(1) Remove all the tools and equipment from the work area. Make sure the area is 

clean. 

E 
MDC-02K1003 

Revision E 

BOEING PROPRIETARY INFORMATION 

Copyright © - The Boeing Company - Unpublished Work 

Page A30

SCI 27-3 - MD-11 HORIZONTAL STABILIZER ACTUATOR LUBRICATION 

(cont’d) 

(2) Close this access panel: 

Number Name/Location

311AB AFT FUSELAGE 

(3) Remove the safety tags and close these circuit breakers: 

AVIONICS, FLIGHT CONTROL DC BUS 1 

Row Col Number Name

C 8 B1-693 AUTO PITCH TRIM 1 

AVIONICS, MISC DC BUS 2 

Row Col Number Name

F 3 B1-507 PRIMARY HORIZ STAB TRIM 

OVERHEAD, RIGHT EMER DC BUS 

Row Col Number Name

E 26 B1-694 AUTO PITCH TRIM 2 

(4) Remove the “DO NOT OPERATE” tag from the horizontal stabilizer suitcase 

handles on the control pedestal. 

E 
MDC-02K1003 

Revision E 

BOEING PROPRIETARY INFORMATION 

Copyright © - The Boeing Company - Unpublished Work 

Page A31

SCI 27-3 - MD-11 HORIZONTAL STABILIZER ACTUATOR LUBRICATION 

(cont’d) 

Figure 1 

E 
MDC-02K1003 

Revision E 

BOEING PROPRIETARY INFORMATION 

Copyright © - The Boeing Company - Unpublished Work 

Page A32

SCI 27-3 - MD-11 HORIZONTAL STABILIZER ACTUATOR LUBRICATION 

(cont’d) 

6. Is test equipment needed?

No test equipment is required. 

7. What is pass/fail criteria?

This SCI provides a lubrication servicing procedure; pass/fail criteria do not apply. 

8. What is SCI interval?

The horizontal stabilizer actuator lubrication procedure shall be performed at intervals 

not to exceed 1,800 flight hours. 

E 
MDC-02K1003 

Revision E 

BOEING PROPRIETARY INFORMATION 

Copyright © - The Boeing Company - Unpublished Work 

Page A33

SCI 27-4 - DC-10 HORIZONTAL STABILIZER ACTUATOR WEAR CHECK 

(AIRCRAFT WITH TWO DRIVE CHAINS) 

1. What model does this SCI apply to?

DC-10 series aircraft with two horizontal stabilizer actuator drive chains (service bulletin 

DC10-27-162 incorporated) 

2. What part or LRU is being checked?

Horizontal stabilizer actuator 

3. What failure mode is being looked for?

This SCI checks for wear rather than a failure mode. A wear check is being performed to 

make certain that actuator and actuator-to-horizontal stabilizer attach point wear has not 

exceeded the service limits. 

4. How is it found?

Check the actuator and acme screw attach point for wear as detailed in number 5 below. 

5. What tasks are to be performed?

Perform the following horizontal stabilizer actuator wear check procedure: 

1. General

A. The left and right horizontal stabilizer actuators are located forward of the horizontal 

stabilizer constant section. 

B. Access to horizontal stabilizer actuators is through access door 311AB, zone 311, in the 

lower aft fuselage compartment. 

2. Equipment and Materials

NOTE: Equivalent substitutes may be used instead of the following listed items: 

Name and Number

Gage set 

(DZZ7121-501) 

E 
MDC-02K1003 

Revision E 

BOEING PROPRIETARY INFORMATION 

Copyright © - The Boeing Company - Unpublished Work 

Page A34

SCI 27-4 - DC-10 HORIZONTAL STABILIZER ACTUATOR WEAR CHECK 

(AIRCRAFT WITH TWO DRIVE CHAINS) 

(cont’d) 

Torque Wrench 

(200 foot-pounds capacity) 

Torque Wrench 

(30 to 60 inchpounds range) 

Force indicator 

(20 to 25 pounds 

range) 

Quill Shaft 

Installation tool 

(DZZ7291-1) 

Tester, drive 

chain tension 

(DZZ7293-1) 

3. Check Horizontal Stabilizer Actuator Wear Tolerances

WARNING: BEFORE PRESSURIZING HYDRAULIC SYSTEMS, MAKE CERTAIN 

THAT LANDING GEAR GROUND LOCKPINS ARE INSTALLED AND 

THAT APPLICABLE CONTROLS ARE IN CORRECT POSITION TO 

PREVENT INADVERTENT OPERATION OF LANDING GEAR AND 

FLIGHT CONTROL SYSTEMS. 

A. Pressurize hydraulic systems 1 and 3 (Ref. DC-10 MM 29-00-00, Page 201). 

WARNING: BEFORE MOVING HORIZONTAL STABILIZER TRIM CONTROLS, 

MAKE CERTAIN THAT AREAS AROUND HORIZONTAL 

STABILIZER AND ELEVATORS ARE CLEAR OF PERSONNEL AND 

EQUIPMENT AND THAT UPPER TAIL CONE DOORS ARE CLOSED. 

B. Using the horizontal stabilizer trim handles on the control pedestal, move the stabilizer to 

the zero (neutral) position. 

E 
MDC-02K1003 

Revision E 

BOEING PROPRIETARY INFORMATION 

Copyright © - The Boeing Company - Unpublished Work 

Page A35

SCI 27-4 - DC-10 HORIZONTAL STABILIZER ACTUATOR WEAR CHECK 

(AIRCRAFT WITH TWO DRIVE CHAINS) 

(cont’d) 

C. Manually actuate the primary trim control valves located on the aft pressure bulkhead to 

align both actuators as shown in Figure 1, Views A and B. 

NOTE: This procedure indexes the horizontal stabilizer actuators correctly to ensure the 

proper re-installation of the drive chains. 

D. Shut off the hydraulic pressure source. 

E. Make sure that all three hydraulic systems are depressurized (Ref. DC-10 MM 29-00-00, 

Page 201). 

F. Open and tag the following circuit breakers: 

WARNING: TAG AND SAFETY CIRCUIT BREAKERS. 

 Circuit Breaker Panel Location Panel Area

AUTO PITCH TRIM A Avionics DC BUS 1 

AUTO PITCH TRIM B Avionics DC BUS 3 

HOR STAB ALTN TRIM CONT Avionics DC BUS 3 

PRIMARY HORIZ STAB TRIM Upper Main DC BUS 2 

G. Put a “DO NOT OPERATE” tag on the horizontal stabilizer trim handles on the control 

pedestal. 

CAUTION: QUILL SHAFT WILL DROP IF IT IS NOT SUPPORTED WHEN CROSS 

BOLT IS REMOVED. 

H. Remove the cross bolt at the bottom of quill shaft and carefully remove the quill shaft. 

I. Check the first actuator; either the left or right actuator may be checked first (Ref. Figure 

2). 

(1) Loosen the drive chain on the actuator not being checked. 

NOTE: This procedure should provide enough slack in the drive chain to remove 

the chain from the actuator sprocket without disconnecting the chain 

master link. 

E 
MDC-02K1003 

Revision E 

BOEING PROPRIETARY INFORMATION 

Copyright © - The Boeing Company - Unpublished Work 

Page A36

SCI 27-4 - DC-10 HORIZONTAL STABILIZER ACTUATOR WEAR CHECK 

(AIRCRAFT WITH TWO DRIVE CHAINS) 

(cont’d) 

(a) Loosen and disconnect the turnbuckle at the drive chain idler sprocket to 

relieve the tension on the drive chain, and rotate the idler sprocket clear of the 

chain. 

(b) Remove the drive chain from the acme nut sprocket. 

(2) Install the gauge set torque adapter on the actuator not being checked. 

(3) Clean any grease or loose material from the surfaces of the horizontal stabilizer 

fitting and the acme nut hub where the indicator probes will touch on the actuator 

being checked. 

(4) Install the gauge set indicators and restraint on the actuator being checked. 

(a) Position the probe from indicator (A) against the surface of the acme nut hub. 

Move the indicator toward the hub until the probe is compressed 

approximately one half travel and the indicator needle is pointed up. 

(b) Position the probe from indicator (B) against the upper surface of the 

horizontal stabilizer fitting (acme screw attach point). Move the indicator 

toward the fitting until the probe is compressed approximately one half travel 

and the indicator needle is pointed up. 

(c) Install the actuator restraint on the acme nut hub lugs and clamp the end of the 

restraint to the adjacent structural beam. 

(5) Using the torque adapter, rotate the acme nut hub back and forth to relieve the 

tension on the actuator, and then rotate the acme nut hub in a clockwise direction 

until the torque wrench indicates 200 ft-lbs. 

NOTE: The torque shall be 200 ft-lbs, as applied to the actuator screw. With the 

torque adapter installed, the torque wrench reading shall be 200 ft-lbs 

when the wrench handle is parallel to the acme nut hub lugs. The torque 

wrench reading shall be 155 ft-lbs when the wrench handle is 

perpendicular to the nut hub lugs. 

(6) Set both indicator dials to the zero position. 

(7) Rotate the acme nut hub in a counterclockwise direction until the torque wrench 

indicates 200 ft-lbs. 

E 
MDC-02K1003 

Revision E 

BOEING PROPRIETARY INFORMATION 

Copyright © - The Boeing Company - Unpublished Work 

Page A37

SCI 27-4 - DC-10 HORIZONTAL STABILIZER ACTUATOR WEAR CHECK 

(AIRCRAFT WITH TWO DRIVE CHAINS) 

(cont’d) 

(8) Record the amount of indicator needle movement on each indicator. 

NOTE: The two indicator needles will move in opposite directions during the 

check. The amount of movement for the needle that moves in the positive 

direction can be read directly from the indicator scale. The amount of 

movement for the needle that moves in the negative direction must be 

calculated. 

(9) Rotate the acme nut hub in a clockwise direction until the torque wrench indicates 

200 ft-lbs, and check that both indicators have returned to the zero reading. 

(10) Reset the indicators to read zero, if necessary. 

(11) Repeat steps (7) through (10) until three consecutive readings are obtained on each 

indicator that are no more than 0.003 inch apart, with a return to the zero reading 

each time. 

(12) Using the highest of the three readings obtained from each indicator in step (11), do 

any of the following work items that apply. 

(a) If the nut-to-screw reading (indicator A) is more than 0.068 inch, replace the 

actuator. 

(b) If the screw-to-stabilizer-connection reading (indicator B) is more than 0.023 

inch, repair the connection as necessary. 

(c) If the combination of readings (indicators A and B) is more than 0.080 inch, 

replace the actuator and/or repair the connection as necessary. 

J. Perform steps I.(1) through I.(12) on the second actuator being checked. 

K. Remove the gauge set indicators, restraint, and torque adaptor from actuators. 

L. Make certain that both actuators are aligned and positioned as shown in Figure 1, Views 

A and B 

M. Place the drive chains on the acme nut sprockets. 

(1) Position the master links at Points B as shown in Figure 1. 

E 
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Revision E 

BOEING PROPRIETARY INFORMATION 

Copyright © - The Boeing Company - Unpublished Work 

Page A38

SCI 27-4 - DC-10 HORIZONTAL STABILIZER ACTUATOR WEAR CHECK 

(AIRCRAFT WITH TWO DRIVE CHAINS) 

(cont’d) 

(2) Make certain that the slack is removed from the sections of the chains located on 

the forward side of the acme nut sprockets. 

CAUTION: DO NOT EXCEED 60 INCH-POUNDS OF TORQUE ON IDLER 

SPROCKET TURNBUCKLES. 

(3) Connect the turnbuckles at the idler sprockets, and tighten each turnbuckle to a 

torque of 30 to 60 inch-pounds. While tightening the turnbuckles, check to see that 

the acme nut sprockets are free to rotate so that the chain tensions can equalize. 

(4) Safety the idler sprocket turnbuckles with clips. 

N. Check the tension of each drive chain (Ref. DC-10 MM 27-44-01, paragraph 3.B., Install 

Acme Screw Actuator). 

O. Check the dimensions of each actuator (Ref. DC-10 MM 27-44-01, paragraph 3.B., 

Install Acme Screw Actuator). 

P. Install the quill shaft (Ref. DC-10 MM 27-44-01, paragraph 3.B., Install Acme Screw 

Actuator). 

Q. Lubricate the drive chains (Ref. DC-10 MM 12-21-03, figure 305). 

R. Remove the safety tags and close the following circuit breakers: 

 Circuit Breaker Panel Location Panel Area

AUTO PITCH TRIM A Avionics DC BUS 1 

AUTO PITCH TRIM B Avionics DC BUS 3 

HOR STAB ALTN TRIM CONT Avionics DC BUS 3 

PRIMARY HORIZ STAB TRIM Upper Main DC BUS 2 

S. Remove the “DO NOT OPERATE” tag from the horizontal stabilizer trim handles on the 

control pedestal. 

E 
MDC-02K1003 

Revision E 

BOEING PROPRIETARY INFORMATION 

Copyright © - The Boeing Company - Unpublished Work 

Page A39

SCI 27-4 - DC-10 HORIZONTAL STABILIZER ACTUATOR WEAR CHECK 

(AIRCRAFT WITH TWO DRIVE CHAINS) 

(cont’d) 

WARNING: BEFORE PRESSURIZING HYDRAULIC SYSTEMS, MAKE CERTAIN 

THAT LANDING GEAR GROUND LOCKPINS ARE INSTALLED AND 

THAT APPLICABLE CONTROLS ARE IN CORRECT POSITION TO 

PREVENT INADVERTENT OPERATION OF LANDING GEAR AND 

FLIGHT CONTROL SYSTEMS. 

T. Pressurize hydraulic systems 1 and 3 (Ref. DC-10 MM 29-00-00, Page 201). 

WARNING: BEFORE MOVING TRIM CONTROLS, MAKE CERTAIN THAT AREAS 

AROUND HORIZONTAL STABILIZER AND ELEVATORS ARE CLEAR 

OF PERSONNEL AND EQUIPMENT AND THAT UPPER TAIL CONE 

DOORS ARE CLOSED. 

U. Using the horizontal stabilizer trim handles on the control pedestal, move the horizontal 

stabilizer to the full aircraft nose up and full aircraft nose down positions, and check the 

actuators for smooth operation without binding. 

V. Move the horizontal stabilizer to the zero (neutral) position. 

W. Shut off the hydraulic pressure source. 

X. Lubricate the horizontal stabilizer actuators (Ref. SCI 27-1 - DC-10 HORIZONTAL 

STABILIZER ACTUATOR LUBRICATION). 

E 
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Revision E 

BOEING PROPRIETARY INFORMATION 

Copyright © - The Boeing Company - Unpublished Work 

Page A40

SCI 27-4 - DC-10 HORIZONTAL STABILIZER ACTUATOR WEAR CHECK 

(AIRCRAFT WITH TWO DRIVE CHAINS) 

(cont’d) 

Figure 1 

E 

DIMENSIONS C & D 

EQUAL WITHIN 0.15 INCH 

GREASE FITTING I ON TOP OF NUT 

(TYPICAL) • 

HOISTING LUG CIRCULAR 

!DENTATION 

INDEX MARKS 

(BOTH ACTUATOR) 

0 

FWD 1 

LOCATE MASTER LINK ~ POINT 

IN THIS AREA B 

VIEW A LOOKING DOWN 

r,..... --'1, I ()~OCRONST\ 

0 

A A of~ 30.49 ± 0.20 INCHES 

VIEW B 

~~t I 

I 

-----.1 

LH ACTUATOR 

SECTION A·A 

VIEW LOOKING DOWN 

30.49 ± 0.20 INCHES 

RH ACTUATOR 

D 

INDEXED TOOTH 

(BOTH ACTUATORS) 

CA2·27-558D 
MDC-02K1003 

Revision E 

BOEING PROPRIETARY INFORMATION 

Copyright © - The Boeing Company - Unpublished Work 

Page A41

SCI 27-4 - DC-10 HORIZONTAL STABILIZER ACTUATOR WEAR CHECK 

(AIRCRAFT WITH TWO DRIVE CHAINS) 

(cont’d) 

Figure 2 

E 

RIGHT AC ACTUATO~E SCREW 

NOTE: 

SHOWN WITH TO CHECK LEGlf~cSTET INSTALLED UATOR 

CA2-27-560 
MDC-02K1003 

Revision E 

BOEING PROPRIETARY INFORMATION 

Copyright © - The Boeing Company - Unpublished Work 

Page A42

SCI 27-4 - DC-10 HORIZONTAL STABILIZER ACTUATOR WEAR CHECK 

(AIRCRAFT WITH TWO DRIVE CHAINS) 

(cont’d) 

6. Is test equipment needed?

A list of the required equipment and materials can be found in paragraph 2. of the 

actuator wear check procedure in number 5 above. 

7. What is pass/fail criteria?

The pass/fail criteria can be found in paragraph 3.I.(12) of the actuator wear check 

procedure in number 5 above. 

8. What is SCI interval?

The actuator wear check shall be performed at intervals not to exceed 15,000 flight hours. 

E 
MDC-02K1003 

Revision E 

BOEING PROPRIETARY INFORMATION 

Copyright © - The Boeing Company - Unpublished Work 

Page A43

SCI 27-5 - DC-10 HORIZONTAL STABILIZER ACTUATOR WEAR CHECK 

(AIRCRAFT WITH FOUR DRIVE CHAINS) 

1. What model does this SCI apply to?

DC-10 series aircraft with four horizontal stabilizer actuator drive chains (service bulletin 

DC10-27-162 not incorporated) 

2. What part or LRU is being checked?

Horizontal stabilizer actuator 

3. What failure mode is being looked for?

This SCI checks for wear rather than a failure mode. A wear check is being performed to 

make certain that actuator and actuator-to-horizontal stabilizer attach point wear has not 

exceeded the service limits. 

4. How is it found?

Check the actuator and acme screw attach point for wear as detailed in number 5 below. 

5. What tasks are to be performed?

Perform the following horizontal stabilizer actuator wear check procedure: 

1. General

A. The left and right horizontal stabilizer actuators are located forward of the horizontal 

stabilizer constant section. 

B. Access to the horizontal stabilizer actuators is through access door 311AB, zone 311, in 

the lower aft fuselage compartment. 

2. Equipment and Materials

NOTE: Equivalent substitutes may be used instead of the following listed items: 

Name and Number

Gage set 

(DZZ7121-501) 

E 
MDC-02K1003 

Revision E 

BOEING PROPRIETARY INFORMATION 

Copyright © - The Boeing Company - Unpublished Work 

Page A44

SCI 27-5 - DC-10 HORIZONTAL STABILIZER ACTUATOR WEAR CHECK 

(AIRCRAFT WITH FOUR DRIVE CHAINS) 

(cont’d) 

Torque Wrench 

(200 foot-pounds capacity) 

Torque Wrench 

(30 to 60 inchpounds range) 

Force indicator 

(20 to 25 pounds 

range) 

Tester, drive 

chain tension 

(DZZ7293-1) 

3. Check Horizontal Stabilizer Actuator Wear Tolerances

WARNING: BEFORE PRESSURIZING HYDRAULIC SYSTEMS, MAKE CERTAIN 

THAT LANDING GEAR GROUND LOCKPINS ARE INSTALLED AND 

THAT APPLICABLE CONTROLS ARE IN CORRECT POSITION TO 

PREVENT INADVERTENT OPERATION OF LANDING GEAR AND 

FLIGHT CONTROL SYSTEMS. 

A. Pressurize hydraulic systems 1 and 3 (Ref. DC-10 MM 29-00-00, Page 201). 

WARNING: BEFORE MOVING HORIZONTAL STABILIZER TRIM CONTROLS, 

MAKE CERTAIN THAT AREAS AROUND HORIZONTAL STABILIZER 

AND ELEVATORS ARE CLEAR OF PERSONNEL AND EQUIPMENT 

AND THAT UPPER TAIL CONE DOORS ARE CLOSED. 

B. Using the horizontal stabilizer trim handles on the control pedestal, move the stabilizer to 

the zero (neutral) position. 

C. Manually actuate the primary trim control valves located on the aft pressure bulkhead to 

align both actuators as shown in Figure 1, Views A and B. 

NOTE: This procedure indexes the horizontal stabilizer actuators correctly to ensure the 

proper re-installation of the drive chains. 

E 
MDC-02K1003 

Revision E 

BOEING PROPRIETARY INFORMATION 

Copyright © - The Boeing Company - Unpublished Work 

Page A45

SCI 27-5 - DC-10 HORIZONTAL STABILIZER ACTUATOR WEAR CHECK 

(AIRCRAFT WITH FOUR DRIVE CHAINS) 

(cont’d) 

D. Shut off the hydraulic pressure source. 

E. Make sure that all three hydraulic systems are depressurized (Ref. DC-10 MM 29-00-00, 

Page 201). 

F. Open and tag the following circuit breakers: 

WARNING: TAG AND SAFETY CIRCUIT BREAKERS. 

 Circuit Breaker Panel Location Panel Area

AUTO PITCH TRIM A Avionics DC BUS 1 

AUTO PITCH TRIM B Avionics DC BUS 3 

HOR STAB ALTN TRIM CONT Avionics DC BUS 3 

PRIMARY HORIZ STAB TRIM Upper Main DC BUS 2 

G. Put a “DO NOT OPERATE” tag on the horizontal stabilizer trim handles on the control 

pedestal. 

H. Check the first actuator; either the left or right actuator may be checked first (Ref. Figure 

2). 

(1) Loosen the drive chains on the actuator not being checked. 

NOTE: This procedure should provide enough slack in the drive chains to remove 

the chains from the actuator acme nut sprockets without disconnecting the 

chain master links. 

(a) Loosen and disconnect the turnbuckles at the drive chain idler sprockets to 

relieve the tension on the drive chains, and rotate the idler sprockets clear of 

the chains. 

(b) Remove the drive chains from the acme nut sprockets. 

(2) Install the gauge set torque adapter on the actuator not being checked. 

(3) Clean any grease or loose material from the surfaces of the horizontal stabilizer 

fitting and the acme nut hub where the indicator probes will touch on the actuator 

being checked. 

E 
MDC-02K1003 

Revision E 

BOEING PROPRIETARY INFORMATION 

Copyright © - The Boeing Company - Unpublished Work 

Page A46

SCI 27-5 - DC-10 HORIZONTAL STABILIZER ACTUATOR WEAR CHECK 

(AIRCRAFT WITH FOUR DRIVE CHAINS) 

(cont’d) 

(4) Install the gauge set indicators and restraint on the actuator being checked. 

(a) Position the probe from indicator (A) against the surface of the acme nut hub. 

Move the indicator toward the hub until the probe is compressed 

approximately one half travel and the indicator needle is pointed up. 

(b) Position the probe from indicator (B) against the upper surface of the 

horizontal stabilizer fitting (acme screw attach point). Move the indicator 

toward the fitting until the probe is compressed approximately one half travel 

and the indicator needle is pointed up. 

(c) Install the actuator restraint on the acme nut hub lugs and clamp the end of the 

restraint to the adjacent structural beam. 

(5) Using the torque adapter, rotate the acme nut hub back and forth to relieve the 

tension on the actuator, and then rotate the acme nut hub in a clockwise direction 

until the torque wrench indicates 200 ft-lbs. 

NOTE: The torque shall be 200 ft-lbs, as applied to the actuator screw. With the 

torque adapter installed, the torque wrench reading shall be 200 ft-lbs 

when the wrench handle is parallel to the acme nut hub lugs. The torque 

wrench reading shall be 155 ft-lbs when the wrench handle is 

perpendicular to the nut hub lugs. 

(6) Set both indicator dials to the zero position. 

(7) Rotate the acme nut hub in a counterclockwise direction until the torque wrench 

indicates 200 ft-lbs. 

(8) Record the amount of indicator needle movement on each indicator. 

NOTE: The two indicator needles will move in opposite directions during the 

check. The amount of movement for the needle that moves in the positive 

direction can be read directly from the indicator scale. The amount of 

movement for the needle that moves in the negative direction must be 

calculated. 

(9) Rotate the acme nut hub in a clockwise direction until the torque wrench indicates 

200 ft-lbs, and check that both indicators have returned to the zero reading. 

(10) Reset the indicators to read zero, if necessary. 

E 
MDC-02K1003 

Revision E 

BOEING PROPRIETARY INFORMATION 

Copyright © - The Boeing Company - Unpublished Work 

Page A47

SCI 27-5 - DC-10 HORIZONTAL STABILIZER ACTUATOR WEAR CHECK 

(AIRCRAFT WITH FOUR DRIVE CHAINS) 

(cont’d) 

(11) Repeat steps (7) through (10) until three consecutive readings are obtained on each 

indicator that are no more than 0.003 inch apart, with a return to the zero reading 

each time. 

(12) Using the highest of the three readings obtained from each indicator in step (11), do 

any of the following work items that apply. 

(a) If the nut-to-screw reading (indicator A) is more than 0.068 inch, replace the 

actuator. 

(b) If the screw-to-stabilizer-connection reading (indicator B) is more than 0.023 

inch, repair the connection as necessary. 

(c) If the combination of readings (indicators A and B) is more than 0.080 inch, 

replace the actuator and/or repair the connection as necessary. 

I. Perform steps H.(1) through H.(12) on the second actuator being checked. 

J. Remove the gauge set indicators, restraint, and torque adaptor from actuators. 

K. Make certain that both actuators are aligned and positioned as shown in Figure 1, Views 

A and B 

L. Place the drive chains on the acme nut sprockets. 

(1) Position the master links at Points B as shown in Figure 1. 

(2) Make certain that the slack is removed from the sections of the chains located on 

the forward side of the acme nut sprockets. 

CAUTION: DO NOT EXCEED 60 INCH-POUNDS OF TORQUE ON IDLER 

SPROCKET TURNBUCKLES. 

(3) Connect the turnbuckles at the idler sprockets, and tighten each turnbuckle to a 

torque of 30 to 60 inch-pounds. While tightening the turnbuckles, check to see that 

the acme nut sprockets are free to rotate so that the chain tensions can equalize. 

(4) Safety the idler sprocket turnbuckles with clips. 

E 
MDC-02K1003 

Revision E 

BOEING PROPRIETARY INFORMATION 

Copyright © - The Boeing Company - Unpublished Work 

Page A48

SCI 27-5 - DC-10 HORIZONTAL STABILIZER ACTUATOR WEAR CHECK 

(AIRCRAFT WITH FOUR DRIVE CHAINS) 

(cont’d) 

M. Check the tension of each drive chain (Ref. DC-10 MM 27-44-01, paragraph 3.B., Install 

Acme Screw Actuator). 

N. Check the dimensions of each actuator (Ref. DC-10 MM 27-44-01, paragraph Install 

Acme Screw Actuator). 

O. Lubricate the drive chains (Ref. DC-10 MM 12-21-03, figure 305). 

P. Remove the safety tags and close the following circuit breakers: 

 Circuit Breaker Panel Location Panel Area

AUTO PITCH TRIM A Avionics DC BUS 1 

AUTO PITCH TRIM B Avionics DC BUS 3 

HOR STAB ALTN TRIM CONT Avionics DC BUS 3 

PRIMARY HORIZ STAB TRIM Upper Main DC BUS 2 

Q. Remove the “DO NOT OPERATE” tag from the horizontal stabilizer trim handles on the 

control pedestal. 

WARNING: BEFORE PRESSURIZING HYDRAULIC SYSTEMS, MAKE CERTAIN 

THAT LANDING GEAR GROUND LOCKPINS ARE INSTALLED AND 

THAT APPLICABLE CONTROLS ARE IN CORRECT POSITION TO 

PREVENT INADVERTENT OPERATION OF LANDING GEAR AND 

FLIGHT CONTROL SYSTEMS. 

R. Pressurize hydraulic systems 1 and 3 (Ref. DC-10 MM 29-00-00, Page 201). 

WARNING: BEFORE MOVING TRIM CONTROLS, MAKE CERTAIN THAT AREAS 

AROUND HORIZONTAL STABILIZER AND ELEVATORS ARE CLEAR 

OF PERSONNEL AND EQUIPMENT AND THAT UPPER TAIL CONE 

DOORS ARE CLOSED. 

S. Using the horizontal stabilizer trim handles on the control pedestal, move horizontal 

stabilizer to the full aircraft nose up and full aircraft nose down positions, and check the 

actuators for smooth operation without binding. 

T. Move the horizontal stabilizer to the zero (neutral) position. 

U. Shut off the hydraulic pressure source. 

E 
MDC-02K1003 

Revision E 

BOEING PROPRIETARY INFORMATION 

Copyright © - The Boeing Company - Unpublished Work 

Page A49

SCI 27-5 - DC-10 HORIZONTAL STABILIZER ACTUATOR WEAR CHECK 

(AIRCRAFT WITH FOUR DRIVE CHAINS) 

(cont’d) 

V. Lubricate the horizontal stabilizer actuators (Ref. SCI 27-1 - DC-10 HORIZONTAL 

STABILIZER ACTUATOR LUBRICATION). E 
MDC-02K1003 

Revision E 

BOEING PROPRIETARY INFORMATION 

Copyright © - The Boeing Company - Unpublished Work 

Page A50

SCI 27-5 - DC-10 HORIZONTAL STABILIZER ACTUATOR WEAR CHECK 

(AIRCRAFT WITH FOUR DRIVE CHAINS) 

(cont’d) 

Figure 1 

E 

DIMENSIONS A & B 

EQUAL WITHIN 0.15 INCH 

A 

NUT STOP 

HOISTING LUG 

NOTE: 

WHEN MAKING AN INDEX CHECK, ASSUMING THE 

LEFT HAND ACTUATOR NUT LUGS ARE EQUAL, 

THERE CAN BE NO PRACTICAL IMPROVEMENT 

MADE IN INDEXING, UNLESS MISALIGNMENT 

OF RIGHT HAND ACTUATOR NUT LUGS ARE 

GREATER THAN 1/2 INCH. 

30.49 +0.20 INCHES 

(2 PLACES) 

VIEW B 

I 

B 

AFT PRESSURE BULKHEAD 

c 

DIMENSIONS C & D 

EQUIAL WITHIN 0.15 INCH 

D 

LOCATE 

IN THIS 

MASTER 

AREA 

UNK ~ B 

VIEW A 

VIEW LOOKING DOWN 

NOTE: 

THIS PROVIDES GROSS 

ADJUSTMENT OF ACTUATORS. 

FOR FINE ADJUSTMENT SEE 

VIEW A 

0 

FWD 

SCREW STOP~-

oO 

FWD 

INDEXED TOOTH 

(BOTH ACTUATORS) 

SECTION B-B 

VIEW LOOKING DOWN 

DC-1 0 WEAR CHECK 4 CHAIN F1 
MDC-02K1003 

Revision E 

BOEING PROPRIETARY INFORMATION 

Copyright © - The Boeing Company - Unpublished Work 

Page A51

SCI 27-5 - DC-10 HORIZONTAL STABILIZER ACTUATOR WEAR CHECK 

(AIRCRAFT WITH FOUR DRIVE CHAINS) 

(cont’d) 

Figure 2 

E 

INDICATOR B 

(MEASURES 

TOLERANCE 

BETWEEN 

ACME SCREW 

~~~B~~r~~~NTAL POINT J ATTACH 

INDICATOR A 

<MEASURES 

TOLERANCE 

BETWEEN 

ACME SCREW 

~~g ~CME NUT 

RIGHT AC ACTUATO_~E SCREW 

CHAIN DRIVE 

TURNBUCKLES 

CA2-27-299A 
MDC-02K1003 

Revision E 

BOEING PROPRIETARY INFORMATION 

Copyright © - The Boeing Company - Unpublished Work 

Page A52

SCI 27-5 - DC-10 HORIZONTAL STABILIZER ACTUATOR WEAR CHECK 

(AIRCRAFT WITH FOUR DRIVE CHAINS) 

(cont’d) 

6. Is test equipment needed?

A list of the required equipment and materials can be found in paragraph 2. of the 

actuator wear check procedure in number 5 above. 

7. What is pass/fail criteria?

The pass/fail criteria can be found in paragraph 3.H.(12) of the actuator wear check 

procedure in number 5 above. 

8. What is SCI interval?

The actuator wear check shall be performed at intervals not to exceed 15,000 flight hours. 

E 
MDC-02K1003 

Revision E 

BOEING PROPRIETARY INFORMATION 

Copyright © - The Boeing Company - Unpublished Work 

Page A53

SCI 27-6 - MD-10 HORIZONTAL STABILIZER ACTUATOR WEAR CHECK 

(AIRCRAFT WITH TWO DRIVE CHAINS) 

1. What model does this SCI apply to?

MD-10 series aircraft with two horizontal stabilizer actuator drive chains (service bulletin 

DC10-27-162 incorporated) 

2. What part or LRU is being checked?

Horizontal stabilizer actuator 

3. What failure mode is being looked for?

This SCI checks for wear rather than a failure mode. A wear check is being performed to 

make certain that actuator and actuator-to-horizontal stabilizer attach point wear has not 

exceeded the service limits. 

4. How is it found?

Check the actuator and acme screw attach point for wear as detailed in number 5 below. 

5. What tasks are to be performed?

Perform the following horizontal stabilizer actuator wear check procedure: 

1. General

A. The left and right horizontal stabilizer actuators are located forward of the horizontal 

stabilizer constant section. 

B. Access to horizontal stabilizer actuators is through access door 311AB, zone 311, in the 

lower aft fuselage compartment. 

2. Equipment and Materials

NOTE: Equivalent substitutes may be used instead of the following listed items: 

Name and Number

Gage set (DZZ7121-501) 

E 
MDC-02K1003 

Revision E 

BOEING PROPRIETARY INFORMATION 

Copyright © - The Boeing Company - Unpublished Work 

Page A54

SCI 27-6 - MD-10 HORIZONTAL STABILIZER ACTUATOR WEAR CHECK 

(AIRCRAFT WITH TWO DRIVE CHAINS) 

(cont’d) 

Torque Wrenches (200 foot-pounds capacity) 

(30 to 60 inch-pounds range) 

Force indicator (20 to 25 pounds range) 

Quill Shaft Installation tool (DZZ7291-1) 

Tester, drive chain tension (DZZ7293-1) 

3. Check Horizontal Stabilizer Actuator Wear Tolerances

WARNING: BEFORE PRESSURIZING HYDRAULIC SYSTEMS, MAKE CERTAIN 

THAT LANDING GEAR GROUND LOCKPINS ARE INSTALLED AND 

THAT APPLICABLE CONTROLS ARE IN CORRECT POSITION TO 

PREVENT INADVERTENT OPERATION OF LANDING GEAR AND 

FLIGHT CONTROL SYSTEMS. 

A. Pressurize hydraulic systems 1 and 3 (MD-10 AMM, PAGEBLOCK 29-00-00/201). 

WARNING: BEFORE MOVING HORIZONTAL STABILIZER TRIM CONTROLS, 

MAKE CERTAIN THAT AREAS AROUND HORIZONTAL 

STABILIZER AND ELEVATORS ARE CLEAR OF PERSONNEL AND 

EQUIPMENT AND THAT UPPER TAIL CONE DOORS ARE CLOSED. 

B. Using the horizontal stabilizer trim handles on the control pedestal, move the stabilizer to 

the zero (neutral) position. 

C. Manually actuate the primary trim control valves located on the aft pressure bulkhead to 

align both actuators as shown in Figure 1, Views A and B. 

NOTE: This procedure indexes the horizontal stabilizer actuators correctly to 

ensure the proper re-installation of the drive chains. 

D. Shut off the hydraulic pressure source. 

E. Make sure that all three hydraulic systems are depressurized (MD-10 AMM, 

PAGEBLOCK 29-00-00/201). 

E 
MDC-02K1003 

Revision E 

BOEING PROPRIETARY INFORMATION 

Copyright © - The Boeing Company - Unpublished Work 

Page A55

SCI 27-6 - MD-10 HORIZONTAL STABILIZER ACTUATOR WEAR CHECK 

(AIRCRAFT WITH TWO DRIVE CHAINS) 

(cont’d) 

WARNING: TAG AND USE SAFETY CLIPS TO SAFETY THE CIRCUIT 

BREAKERS. IF THE CIRCUIT BREAKERS ARE NOT OPENED, 

TAGGED, AND SAFETIED, INJURY TO PERSONS AND DAMAGE TO 

EQUIPMENT CAN OCCUR. 

F. Open these circuit breakers and install safety tags: 

AVIONICS, FLIGHT CONTROL DC BUS 1 

Row Col Number Name

C 8 B1-693 AUTO PITCH TRIM 1 

AVIONICS, MISC DC BUS 2 

Row Col Number Name

F 3 B1-507 PRIMARY HORIZ STAB TRIM 

OVERHEAD, RIGHT EMER DC BUS 

Row Col Number Name

E 26 B1-694 AUTO PITCH TRIM 2 

G. Put a “DO NOT OPERATE” tag on the horizontal stabilizer trim handles on the control 

pedestal. 

CAUTION: QUILL SHAFT WILL DROP IF IT IS NOT SUPPORTED WHEN CROSS 

BOLT IS REMOVED. 

H. Remove the cross bolt at the bottom of quill shaft and carefully remove the quill shaft. 

I. Check the first actuator; either the left or right actuator may be checked first (Figure 2). 

(1) Loosen the drive chain on the actuator not being checked. 

NOTE: This procedure should provide enough slack in the drive chain to remove 

the chain from the actuator acme nut sprocket without disconnecting the 

chain master link. 

E 
MDC-02K1003 

Revision E 

BOEING PROPRIETARY INFORMATION 

Copyright © - The Boeing Company - Unpublished Work 

Page A56

SCI 27-6 - MD-10 HORIZONTAL STABILIZER ACTUATOR WEAR CHECK 

(AIRCRAFT WITH TWO DRIVE CHAINS) 

(cont’d) 

(a) Loosen and disconnect the turnbuckle at the drive chain idler sprocket to 

relieve the tension on the drive chain, and rotate the idler sprocket clear of the 

chain. 

(b) Remove the drive chain from the acme nut sprocket. 

(2) Install the gauge set torque adapter on the actuator not being checked. 

(3) Clean any grease or loose material from the surfaces of the horizontal stabilizer 

fitting and the acme nut hub where the indicator probes will touch on the actuator 

being checked. 

(4) Install the gauge set indicators and restraint on the actuator being checked. 

(a) Position the probe from indicator (A) against the surface of the acme nut hub. 

Move the indicator toward the hub until the probe is compressed 

approximately one half travel and the indicator needle is pointed up. 

(b) Position the probe from indicator (B) against the upper surface of the 

horizontal stabilizer fitting (acme screw attach point). Move the indicator 

toward the fitting until the probe is compressed approximately one half travel 

and the indicator needle is pointed up. 

(c) Install the actuator restraint on the acme nut hub lugs and clamp the end of the 

restraint to the adjacent structural beam. 

(5) Using the torque adapter, rotate the acme nut hub back and forth to relieve the 

tension on the actuator, and then rotate the acme nut hub in a clockwise direction 

until the torque wrench indicates 200 ft-lbs. 

NOTE: The torque shall be 200 ft-lbs, as applied to the actuator screw. With the 

torque adapter installed, the torque wrench reading shall be 200 ft-lbs 

when the wrench handle is parallel to the acme nut hub lugs. The torque 

wrench reading shall be 155 ft-lbs when the wrench handle is 

perpendicular to the nut hub lugs. 

(6) Set both indicator dials to the zero position. 

(7) Rotate the acme nut hub in a counterclockwise direction until the torque wrench 

indicates 200 ft-lbs. 

E 
MDC-02K1003 

Revision E 

BOEING PROPRIETARY INFORMATION 

Copyright © - The Boeing Company - Unpublished Work 

Page A57

SCI 27-6 - MD-10 HORIZONTAL STABILIZER ACTUATOR WEAR CHECK 

(AIRCRAFT WITH TWO DRIVE CHAINS) 

(cont’d) 

(8) Record the amount of indicator needle movement on each indicator. 

NOTE: The two indicator needles will move in opposite directions during the 

check. The amount of movement for the needle that moves in the positive 

direction can be read directly from the indicator scale. The amount of 

movement for the needle that moves in the negative direction must be 

calculated. 

(9) Rotate the acme nut hub in a clockwise direction until the torque wrench indicates 

200 ft-lbs, and check that both indicators have returned to the zero reading. 

(10) Reset the indicators to read zero, if necessary. 

(11) Repeat steps (7) through (10) until three consecutive readings are obtained on each 

indicator that are no more than 0.003 inch apart, with a return to the zero reading 

each time. 

(12) Using the highest of the three readings obtained from each indicator in step (11), do 

any of the following work items that apply. 

(a) If the nut-to-screw reading (indicator A) is more than 0.068 inch, replace the 

actuator. 

(b) If the screw-to-stabilizer-connection reading (indicator B) is more than 0.023 

inch, repair the connection as necessary. 

(c) If the combination of readings (indicators A and B) is more than 0.080 inch, 

replace the actuator and/or repair the connection as necessary. 

J. Perform steps I.(1) through I.(12) on the second actuator being checked. 

K. Remove the gauge set indicators, restraint, and torque adaptor from actuators. 

L. Make certain that both actuators are aligned and positioned as shown in Figure 1, Views 

A and B. 

M. Place the drive chains on the acme nut sprockets. 

(1) Position the master links at Points B as shown in Figure 1. 

E 
MDC-02K1003 

Revision E 

BOEING PROPRIETARY INFORMATION 

Copyright © - The Boeing Company - Unpublished Work 

Page A58

SCI 27-6 - MD-10 HORIZONTAL STABILIZER ACTUATOR WEAR CHECK 

(AIRCRAFT WITH TWO DRIVE CHAINS) 

(cont’d) 

(2) Make certain that the slack is removed from the sections of the chains located on 

the forward side of the acme nut sprockets. 

CAUTION: DO NOT EXCEED 60 INCH-POUNDS OF TORQUE ON IDLER 

SPROCKET TURNBUCKLES. 

(3) Connect the turnbuckles at the idler sprockets, and tighten each turnbuckle to a 

torque of 30 to 60 inch-pounds. While tightening the turnbuckles, check to see that 

the acme nut sprockets are free to rotate so that the chain tensions can equalize. 

(4) Safety the idler sprocket turnbuckles with clips. 

N. Check the tension of each drive chain (MD-10 AMM, PAGEBLOCK 27-44-01/201, 

INSTALL ACME SCREW ACTUATOR). 

O. Check the dimensions of each actuator (MD-10 AMM, PAGEBLOCK 27-44-01/201, 

INSTALL ACME SCREW ACTUATOR). 

P. Install the quill shaft (MD-10 AMM, PAGEBLOCK 27-44-01/201, INSTALL ACME 

SCREW ACTUATOR). 

Q. Lubricate the drive chains (MD-10 AMM, PAGEBLOCK 12-21-03/301, HORIZONTAL 

STABILIZER CONSTANT SECTION LUBRICATION). 

R. Remove the safety tags and close these circuit breakers: 

AVIONICS, FLIGHT CONTROL DC BUS 1 

Row Col Number Name

C 8 B1-693 AUTO PITCH TRIM 1 

AVIONICS, MISC DC BUS 2 

Row Col Number Name

F 3 B1-507 PRIMARY HORIZ STAB TRIM 

E 
MDC-02K1003 

Revision E 

BOEING PROPRIETARY INFORMATION 

Copyright © - The Boeing Company - Unpublished Work 

Page A59

SCI 27-6 - MD-10 HORIZONTAL STABILIZER ACTUATOR WEAR CHECK 

(AIRCRAFT WITH TWO DRIVE CHAINS) 

(cont’d) 

OVERHEAD, RIGHT EMER DC BUS 

Row Col Number Name

E 26 B1-694 AUTO PITCH TRIM 2 

S. Remove the “DO NOT OPERATE” tag from the horizontal stabilizer trim handles on the 

control pedestal. 

WARNING: BEFORE PRESSURIZING HYDRAULIC SYSTEMS, MAKE CERTAIN 

THAT LANDING GEAR GROUND LOCKPINS ARE INSTALLED AND 

THAT APPLICABLE CONTROLS ARE IN CORRECT POSITION TO 

PREVENT INADVERTENT OPERATION OF LANDING GEAR AND 

FLIGHT CONTROL SYSTEMS. 

T. Pressurize hydraulic systems 1 and 3 (MD-10 AMM, PAGEBLOCK 29-00-00/201). 

WARNING: BEFORE MOVING TRIM CONTROLS, MAKE CERTAIN THAT AREAS 

AROUND HORIZONTAL STABILIZER AND ELEVATORS ARE 

CLEAR OF PERSONNEL AND EQUIPMENT AND THAT UPPER TAIL 

CONE DOORS ARE CLOSED. 

U. Using the horizontal stabilizer trim handles on the control pedestal, move horizontal 

stabilizer to the full aircraft nose up and full aircraft nose down positions, and check the 

actuators for smooth operation without binding. 

V. Move the horizontal stabilizer to the zero (neutral) position. 

W. Shut off the hydraulic pressure source. 

X. Lubricate the horizontal stabilizer actuators (SCI 27-2 - MD-10 HORIZONTAL 

STABILIZER ACTUATOR LUBRICATION). 

E 
MDC-02K1003 

Revision E 

BOEING PROPRIETARY INFORMATION 

Copyright © - The Boeing Company - Unpublished Work 

Page A60

SCI 27-6 - MD-10 HORIZONTAL STABILIZER ACTUATOR WEAR CHECK 

(AIRCRAFT WITH TWO DRIVE CHAINS) 

(cont’d) 

Figure 1 

E 

DIMENSIONS C & D 

EQUAL WITHIN 0.15 INCH 

GREASE FITTING I ON TOP OF NUT 

(TYPICAL) • 

HOISTING LUG CIRCULAR 

!DENTATION 

INDEX MARKS 

(BOTH ACTUATOR) 

0 

FWD 1 

LOCATE MASTER LINK ~ POINT 

IN THIS AREA B 

VIEW A LOOKING DOWN 

r,..... --'1, I ()~OCRONST\ 

0 

A A of~ 30.49 ± 0.20 INCHES 

VIEW B 

~~t I 

I 

-----.1 

LH ACTUATOR 

SECTION A·A 

VIEW LOOKING DOWN 

30.49 ± 0.20 INCHES 

RH ACTUATOR 

D 

INDEXED TOOTH 

(BOTH ACTUATORS) 

CA2·27-558D 
MDC-02K1003 

Revision E 

BOEING PROPRIETARY INFORMATION 

Copyright © - The Boeing Company - Unpublished Work 

Page A61

SCI 27-6 - MD-10 HORIZONTAL STABILIZER ACTUATOR WEAR CHECK 

(AIRCRAFT WITH TWO DRIVE CHAINS) 

(cont’d) 

Figure 2 

E 

RIGHT AC ACTUATO~E SCREW 

NOTE: 

SHOWN WITH TO CHECK LEGlf~cSTET INSTALLED UATOR 

CA2-27-560 
MDC-02K1003 

Revision E 

BOEING PROPRIETARY INFORMATION 

Copyright © - The Boeing Company - Unpublished Work 

Page A62

SCI 27-6 - MD-10 HORIZONTAL STABILIZER ACTUATOR WEAR CHECK 

(AIRCRAFT WITH TWO DRIVE CHAINS) 

(cont’d) 

6. Is test equipment needed?

A list of the required equipment and materials can be found in paragraph 2. of the 

actuator wear check procedure in number 5 above. 

7. What is pass/fail criteria?

The pass/fail criteria can be found in paragraph 3.I.(12) of the actuator wear check 

procedure in number 5 above. 

8. What is SCI interval?

The actuator wear check shall be performed at intervals not to exceed 15,000 flight hours. 

E 
MDC-02K1003 

Revision E 

BOEING PROPRIETARY INFORMATION 

Copyright © - The Boeing Company - Unpublished Work 

Page A63

SCI 27-7 - MD-10 HORIZONTAL STABILIZER ACTUATOR WEAR CHECK 

(AIRCRAFT WITH FOUR DRIVE CHAINS) 

1. What model does this SCI apply to?

MD-10 series aircraft with four horizontal stabilizer actuator drive chains (service 

bulletin DC10-27-162 not incorporated) 

2. What part or LRU is being checked?

Horizontal stabilizer actuator 

3. What failure mode is being looked for?

This SCI checks for wear rather than a failure mode. A wear check is being performed to 

make certain that actuator and actuator-to-horizontal stabilizer attach point wear has not 

exceeded the service limits. 

4. How is it found?

Check the actuator and acme screw attach point for wear as detailed in number 5 below. 

5. What tasks are to be performed?

Perform the following horizontal stabilizer actuator wear check procedure: 

1. General

A. The left and right horizontal stabilizer actuators are located forward of the horizontal 

stabilizer constant section. 

B. Access to the horizontal stabilizer actuators is through access door 311AB, zone 311, in 

the lower aft fuselage compartment. 

2. Equipment and Materials

NOTE: Equivalent substitutes may be used instead of the following listed items: 

Name and Number

Gage set (DZZ7121-501) 

E 
MDC-02K1003 

Revision E 

BOEING PROPRIETARY INFORMATION 

Copyright © - The Boeing Company - Unpublished Work 

Page A64

SCI 27-7 - MD-10 HORIZONTAL STABILIZER ACTUATOR WEAR CHECK 

(AIRCRAFT WITH FOUR DRIVE CHAINS) 

(cont’d) 

Torque Wrenches (200 foot-pounds capacity) 

(30 to 60 inch-pounds range) 

Force indicator (20 to 25 pounds range) 

Tester, drive chain tension (DZZ7293-1) 

3. Check Horizontal Stabilizer Actuator Wear Tolerances

WARNING: BEFORE PRESSURIZING HYDRAULIC SYSTEMS, MAKE CERTAIN 

THAT LANDING GEAR GROUND LOCKPINS ARE INSTALLED AND 

THAT APPLICABLE CONTROLS ARE IN CORRECT POSITION TO 

PREVENT INADVERTENT OPERATION OF LANDING GEAR AND 

FLIGHT CONTROL SYSTEMS. 

A. Pressurize hydraulic systems 1 and 3 (MD-10 AMM, PAGEBLOCK 29-00-00/201). 

WARNING: BEFORE MOVING HORIZONTAL STABILIZER TRIM CONTROLS, 

MAKE CERTAIN THAT AREAS AROUND HORIZONTAL 

STABILIZER AND ELEVATORS ARE CLEAR OF PERSONNEL AND 

EQUIPMENT AND THAT UPPER TAIL CONE DOORS ARE CLOSED. 

B. Using the horizontal stabilizer trim handles on the control pedestal, move the stabilizer to 

the zero (neutral) position. 

C. Manually actuate the primary trim control valves located on the aft pressure bulkhead to 

align both actuators as shown in Figure 1, Views A and B. 

NOTE: This procedure indexes the horizontal stabilizer actuators correctly to ensure the 

proper re-installation of the drive chains. 

D. Shut off the hydraulic pressure source. 

E. Make sure that all three hydraulic systems are depressurized (MD-10 AMM, 

PAGEBLOCK 29-00-00/201). 

E 
MDC-02K1003 

Revision E 

BOEING PROPRIETARY INFORMATION 

Copyright © - The Boeing Company - Unpublished Work 

Page A65

SCI 27-7 - MD-10 HORIZONTAL STABILIZER ACTUATOR WEAR CHECK 

(AIRCRAFT WITH FOUR DRIVE CHAINS) 

(cont’d) 

WARNING: TAG AND USE SAFETY CLIPS TO SAFETY THE CIRCUIT 

BREAKERS. IF THE CIRCUIT BREAKERS ARE NOT OPENED, 

TAGGED, AND SAFETIED, INJURY TO PERSONS AND DAMAGE TO 

EQUIPMENT CAN OCCUR. 

F. Open these circuit breakers and install safety tags: 

AVIONICS, FLIGHT CONTROL DC BUS 1 

Row Col Number Name

C 8 B1-693 AUTO PITCH TRIM 1 

AVIONICS, MISC DC BUS 2 

Row Col Number Name

F 3 B1-507 PRIMARY HORIZ STAB TRIM 

OVERHEAD, RIGHT EMER DC BUS 

Row Col Number Name

E 26 B1-694 AUTO PITCH TRIM 2 

G. Put a “DO NOT OPERATE” tag on the horizontal stabilizer trim handles on the control 

pedestal. 

H. Check the first actuator; either the left or right actuator may be checked first (Figure 2). 

(1) Loosen the drive chains on the actuator not being checked. 

NOTE: This procedure should provide enough slack in the drive chains to remove 

the chains from the actuator acme nut sprockets without disconnecting the 

chain master links. 

(a) Loosen and disconnect the turnbuckles at the drive chain idler sprockets to 

relieve the tension on the drive chains, and rotate the idler sprockets clear of 

the chains. 

(b) Remove the drive chains from the acme nut sprockets. 

(2) Install the gauge set torque adapter on the actuator not being checked. 

SCI 27-7 - MD-10 HORIZONTAL STABILIZER ACTUATOR WEAR CHECK 

E 
MDC-02K1003 

Revision E 

BOEING PROPRIETARY INFORMATION 

Copyright © - The Boeing Company - Unpublished Work 

Page A66

(AIRCRAFT WITH FOUR DRIVE CHAINS) 

(cont’d) 

(3) Clean any grease or loose material from the surfaces of the horizontal stabilizer 

fitting and the acme nut hub where the indicator probes will touch on the actuator 

being checked. 

(4) Install the gauge set indicators and restraint on the actuator being checked. 

(a) Position the probe from indicator (A) against the surface of the acme nut hub. 

Move the indicator toward the hub until the probe is compressed 

approximately one half travel and the indicator needle is pointed up. 

(b) Position the probe from indicator (B) against the upper surface of the 

horizontal stabilizer fitting (acme screw attach point). Move the indicator 

toward the fitting until the probe is compressed approximately one half travel 

and the indicator needle is pointed up. 

(c) Install the actuator restraint on the acme nut hub lugs and clamp the end of the 

restraint to the adjacent structural beam. 

(5) Using the torque adapter, rotate the acme nut hub back and forth to relieve the 

tension on the actuator, and then rotate the acme nut hub in a clockwise direction 

until the torque wrench indicates 200 ft-lbs. 

NOTE: The torque shall be 200 ft-lbs, as applied to the actuator screw. With the 

torque adapter installed, the torque wrench reading shall be 200 ft-lbs 

when the wrench handle is parallel to the acme nut hub lugs. The torque 

wrench reading shall be 155 ft-lbs when the wrench handle is 

perpendicular to the nut hub lugs. 

(6) Set both indicator dials to the zero position. 

(7) Rotate the acme nut hub in a counterclockwise direction until the torque wrench 

indicates 200 ft-lbs. 

(8) Record the amount of indicator needle movement on each indicator. 

NOTE: The two indicator needles will move in opposite directions during the 

check. The amount of movement for the needle that moves in the positive 

direction can be read directly from the indicator scale. The amount of 

movement for the needle that moves in the negative direction must be 

calculated. 

E 
MDC-02K1003 

Revision E 

BOEING PROPRIETARY INFORMATION 

Copyright © - The Boeing Company - Unpublished Work 

Page A67

SCI 27-7 - MD-10 HORIZONTAL STABILIZER ACTUATOR WEAR CHECK 

(AIRCRAFT WITH FOUR DRIVE CHAINS) 

(cont’d) 

(9) Rotate the acme nut hub in a clockwise direction until the torque wrench indicates 

200 ft-lbs, and check that both indicators have returned to the zero reading. 

(10) Reset the indicators to read zero, if necessary. 

(11) Repeat steps (7) through (10) until three consecutive readings are obtained on each 

indicator that are no more than 0.003 inch apart, with a return to the zero reading 

each time. 

(12) Using the highest of the three readings obtained from each indicator in step (11), do 

any of the following work items that apply. 

(a) If the nut-to-screw reading (indicator A) is more than 0.068 inch, replace the 

actuator. 

(b) If the screw-to-stabilizer-connection reading (indicator B) is more than 0.023 

inch, repair the connection as necessary. 

(c) If the combination of readings (indicators A and B) is more than 0.080 inch, 

replace the actuator and/or repair the connection as necessary. 

I. Perform steps H.(1) through H.(12) on the second actuator being checked. 

J. Remove the gauge set indicators, restraint, and torque adaptor from actuators. 

K. Make certain that both actuators are aligned and positioned as shown in Figure 1, Views 

A and B 

L. Place the drive chains on the acme nut sprockets. 

(1) Position the master links at Points B as shown in Figure 1. 

(2) Make certain that the slack is removed from the sections of the chains located on 

the forward side of the acme nut sprockets. 

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SCI 27-7 - MD-10 HORIZONTAL STABILIZER ACTUATOR WEAR CHECK 

(AIRCRAFT WITH FOUR DRIVE CHAINS) 

(cont’d) 

CAUTION: DO NOT EXCEED 60 INCH-POUNDS OF TORQUE ON IDLER 

SPROCKET TURNBUCKLES. 

(3) Connect the turnbuckles at the idler sprockets, and tighten each turnbuckle to a 

torque of 30 to 60 inch-pounds. While tightening the turnbuckles, check to see that 

the acme nut sprockets are free to rotate so that the chain tensions can equalize. 

(4) Safety the idler sprocket turnbuckles with clips. 

M. Check the tension of each drive chain (MD-10 AMM, PAGEBLOCK 27-44-01/201, 

INSTALL ACME SCREW ACTUATOR). 

N. Check the dimensions of each actuator (MD-10 AMM, PAGEBLOCK 27-44-01/201, 

INSTALL ACME SCREW ACTUATOR). 

O. Lubricate the drive chains (MD-10 AMM, PAGEBLOCK 12-21-03/301, HORIZONTAL 

STABILIZER CONSTANT SECTION LUBRICATION). 

P. Remove the safety tags and close these circuit breakers: 

AVIONICS, FLIGHT CONTROL DC BUS 1 

Row Col Number Name

C 8 B1-693 AUTO PITCH TRIM 1 

AVIONICS, MISC DC BUS 2 

Row Col Number Name

F 3 B1-507 PRIMARY HORIZ STAB TRIM 

OVERHEAD, RIGHT EMER DC BUS 

Row Col Number Name

E 26 B1-694 AUTO PITCH TRIM 2 

Q. Remove the “DO NOT OPERATE” tag from the horizontal stabilizer trim handles on the 

control pedestal. 

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SCI 27-7 - MD-10 HORIZONTAL STABILIZER ACTUATOR WEAR CHECK 

(AIRCRAFT WITH FOUR DRIVE CHAINS) 

(cont’d) 

WARNING: BEFORE PRESSURIZING HYDRAULIC SYSTEMS, MAKE CERTAIN 

THAT LANDING GEAR GROUND LOCKPINS ARE INSTALLED AND 

THAT APPLICABLE CONTROLS ARE IN CORRECT POSITION TO 

PREVENT INADVERTENT OPERATION OF LANDING GEAR AND 

FLIGHT CONTROL SYSTEMS. 

R. Pressurize hydraulic systems 1 and 3 (MD-10 AMM, PAGEBLOCK 29-00-00/201). 

WARNING: BEFORE MOVING TRIM CONTROLS, MAKE CERTAIN THAT AREAS 

AROUND HORIZONTAL STABILIZER AND ELEVATORS ARE 

CLEAR OF PERSONNEL AND EQUIPMENT AND THAT UPPER TAIL 

CONE DOORS ARE CLOSED. 

S. Using the horizontal stabilizer trim handles on the control pedestal, move horizontal 

stabilizer to the full aircraft nose up and full aircraft nose down positions, and check the 

actuators for smooth operation without binding. 

T. Move the horizontal stabilizer to the zero (neutral) position. 

U. Shut off the hydraulic pressure source. 

V. Lubricate the horizontal stabilizer actuators (SCI 27-2 - MD-10 HORIZONTAL 

STABILIZER ACTUATOR LUBRICATION). 

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SCI 27-7 - MD-10 HORIZONTAL STABILIZER ACTUATOR WEAR CHECK 

(AIRCRAFT WITH FOUR DRIVE CHAINS) 

(cont’d) 

Figure 1 

E 

DIMENSIONS A & B 

EQUAL WITHIN 0.15 INCH 

A 

HOISTING LUG 

NOTE: 

WHEN MAKING AN INDEX CHECK, ASSUMING THE 

LEFT HAND ACTUATOR NUT LUGS ARE EQUAL, 

THERE CAN BE NO PRACTICAL IMPROVEMENT 

MADE IN INDEXING, UNLESS MISALIGNMENT 

OF RIGHT HAND ACTUATOR NUT LUGS ARE 

GREATER THAN 1/2 INCH. 

I 

B 

? 

VIEW B " 

AFT PRESSURE BULKHEAD 

VIEW A 

VIEW LOOKING DOWN 

NOTE: 

THIS PROVIDES GROSS 

ADJUSTMENT OF ACTUATORS. 

FOR FINE ADJUSTMENT SEE 

VIEW A 

c 

0 

FWD 

DIMENSIONS C & D 

EQUIAL WITHIN 0.15 INCH 

D 

INDEXED TOOTH 

(BOTH ACTUATORS) 

SCREW STOP~ 

oO 

FWD 

SECTION B-B 

VIEW LOOKING DOWN 

DC-1 0 WEAR CHECK 4 CHAIN F1 
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SCI 27-7 - MD-10 HORIZONTAL STABILIZER ACTUATOR WEAR CHECK 

(AIRCRAFT WITH FOUR DRIVE CHAINS) 

(cont’d) 

Figure 2 

E 

INDICATOR B 

(MEASURES 

TOLERANCE 

BETWEEN 

ACME SCREW 

~~~B~~r~~~NTAL POINT J ATTACH 

INDICATOR A 

<MEASURES 

TOLERANCE 

BETWEEN 

ACME SCREW 

~~g ~CME NUT 

RIGHT AC ACTUATO_~E SCREW 

CHAIN DRIVE 

TURNBUCKLES 

CA2-27-299A 
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SCI 27-7 - MD-10 HORIZONTAL STABILIZER ACTUATOR WEAR CHECK 

(AIRCRAFT WITH FOUR DRIVE CHAINS) 

(cont’d) 

6. Is test equipment needed?

A list of the required equipment and materials can be found in paragraph 2. of the 

actuator wear check procedure in number 5 above. 

7. What is pass/fail criteria?

The pass/fail criteria can be found in paragraph 3. H.(12) of the actuator wear check 

procedure in number 5 above. 

8. What is SCI interval?

The actuator wear check shall be performed at intervals not to exceed 15,000 flight hours. 

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SCI 27-8 - MD-11 HORIZONTAL STABILIZER ACTUATOR WEAR CHECK 

1. What model does this SCI apply to?

MD-11 series aircraft 

2. What part or LRU is being checked?

Horizontal stabilizer actuator 

3. What failure mode is being looked for?

This SCI checks for wear, rather than a failure mode. A wear check is being performed 

to make certain that the actuator wear and the actuator-to-horizontal stabilizer attach lug 

connection wear have not exceeded the service limits. 

4. How is it found?

Check the actuator and the actuator-to-horizontal stabilizer attach lug connection for wear 

as detailed in number 5 below. 

5. What tasks are to be performed?

Perform the following horizontal stabilizer actuator wear check procedure: 

1. General

A. This procedure has the test instructions for the left and right horizontal stabilizer actuator 

wear tolerance (actuator wear check). 

B. The horizontal stabilizer actuators are installed at the aft pressure bulkhead, forward of 

the horizontal stabilizer. 

C. The referenced TASK numbers apply to the MD-11 AMM. 

2. TEST OF THE HORIZONTAL STABILIZER ACTUATORS

A. Fixtures, Tools, Test and Support Equipment 

(1) Fixtures, Tools, Test and Support Equipment 

NOTE: Equivalent replacements are permitted for the items that follow. 

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SCI 27-8 - MD-11 HORIZONTAL STABILIZER ACTUATOR WEAR CHECK 

(cont’d) 

Table 1 

REFERENCE DESIGNATION 

Not specified Maintenance platform, 10-15 ft (3-5 m) high 

DZZ7121-501 Gage set, horizontal stabilizer jack 

Not specified Torque wrench 200 ft-lb (271 N·m) capacity 

Not specified Torque wrench 30-60 in-lb (3.4-6.8 N·m) range 

Not specified Force indicator 20-25 lbs (9.1-11.3 kg) range 

DZZ7291-1 Torque adapter, horizontal stabilizer spline 

DZZ7293-1 Tension tester, horizontal stabilizer drive chain 

B. Expendable Parts 

(1) Expendable Parts 

Table 2 

REFERENCE/ITEM DESIGNATION IPC 

7 Cotter Pin 27-44-20-001-610 

11 Clip 27-44-20-001-220 

C. References 

Reference Title 

12-24-09-600-801 LUBRICATION OF THE HORIZONTAL STABILIZER 

CONSTANT SECTION (MD-11 AMM, P/B 301) 

27-40-00-710-802 FUNCTIONAL TEST OF THE HORIZONTAL 

STABILIZER RANGE OF MOVEMENT (MD-11 

AMM, P/B 501) 

29-00-00-860-802 APPLY HYDRAULIC PRESSURE, SYSTEM NO. 3 

AUXILIARY PUMPS (MD-11 AMM, P/B 201) 

29-00-00-860-805 REMOVE HYDRAULIC PRESSURE, SYSTEM NO. 3 

AUXILIARY PUMPS (MD-11 AMM, P/B 201) 

29-00-00-860-807 REMOVE HYDRAULIC PRESSURE, SYSTEM NO. 2 

AUXILIARY PUMPS (MD-11 AMM, P/B 201) 

29-00-00-860-808 REMOVE HYDRAULIC PRESSURE, SYSTEM NO. 1 

AUXILIARY PUMPS (MD-11 AMM, P/B 201) 

32-00-00-860-801 SAFETY THE LANDING GEAR FOR 

MAINTENANCE (MD-11 AMM, P/B 201) 

27-44-20-001-220 Illustrated Parts Catalog 

SCI 27-8 - MD-11 HORIZONTAL STABILIZER ACTUATOR WEAR CHECK 

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(cont’d) 

Reference Title 

27-44-20-001-610 Illustrated Parts Catalog 

SCI 27-3 MD-11 HORIZONTAL STABILIZER ACTUATOR 

LUBRICATION (Report Number MDC-02K1003) 

D. Consumable Materials 

NOTE: It is possible that some materials in the Consumable Materials chart cannot be 

used for some or all of the necessary applications. Before you use the materials, 

make sure the types, quantities, and applications of the materials necessary are 

legally permitted in your location. All persons must obey all applicable federal, 

state, local, and provincial laws and regulations when it is necessary to work 

with these materials. 

Description Specification 

Lockwire - .032 Steel Corrosion Resistant DPM 5865 

(NASM20995C) 

E. Access Panels 

Number Name/Location 

311AB AFT FUSELAGE 

F. Job Set-up - Horizontal Stabilizer Actuator Test 

(1) Make sure the landing gear safety pins are installed. (SAFETY THE LANDING 

GEAR FOR MAINTENANCE, TASK 32-00-00-860-801) 

(2) Make sure that this circuit breaker is closed: 

AVIONICS, MISC DC BUS 2 

Row Col Number Name

F 3 B1-507 PRIMARY HORIZ STAB TRIM 

(3) Open this access panel: 

Number Name/Location

311AB AFT FUSELAGE 

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SCI 27-8 - MD-11 HORIZONTAL STABILIZER ACTUATOR WEAR CHECK 

(cont’d) 

G. Procedure - Horizontal Stabilizer Actuator Test 

(1) Pressurize the No. 1 and No. 3 hydraulic systems. (APPLY HYDRAULIC 

PRESSURE, SYSTEM NO. 3 AUXILIARY PUMPS, TASK 29-00-00-860-802) 

WARNING: MAKE SURE THE AREAS AROUND THE HORIZONTAL 

STABILIZER AND ELEVATORS ARE CLEAR BEFORE THE 

HORIZONTAL STABILIZER TRIM IS OPERATED. MAKE SURE 

THE UPPER TAIL CONE DOORS ARE CLOSED. IF THE 

HORIZONTAL STABILIZER SYSTEM ACCIDENTALLY 

OPERATES, IT CAN CAUSE INJURY TO PERSONS AND DAMAGE 

TO EQUIPMENT. 

(2) Align the horizontal stabilizer actuators as follows: (Figure 1) (Figure 2) (Figure 3) 

(Figure 4) 

(a) Move the stabilizer to the zero (neutral) position using the suitcase handles on 

the control pedestal or the control wheel switches. 

(b) Manually operate the primary trim control valves (1) to align the left (2) and 

the right (3) horizontal stabilizer actuators. 

1) Make sure the actuators (2) and (3) are at a height of 30.29-30.69 in. 

(769.4-779.5 mm) as shown in Figure 3. 

NOTE: Measure from the bottom of the acme screw stop to the top of the 

acme nut on the left actuator, and from the bottom of the acme 

screw serrations to the top of the acme nut on the right actuator. 

2) Align the index marks on the left (4) and the right (5) acme nut sprockets 

as shown in Figure 2. 

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SCI 27-8 - MD-11 HORIZONTAL STABILIZER ACTUATOR WEAR CHECK 

(cont’d) 

WARNING: MAKE SURE YOU RELEASE THE PRESSURE FROM ALL 

HYDRAULIC SYSTEMS AND THE SPECIFIED CIRCUIT 

BREAKERS ARE OPEN. IF THE HORIZONTAL STABILIZER TRIM 

SYSTEM ACCIDENTALLY OPERATES, IT CAN CAUSE INJURY TO 

PERSONS AND DAMAGE TO THE EQUIPMENT. 

(3) Make sure that hydraulic pressure has been removed from all three hydraulic 

systems. (REMOVE HYDRAULIC PRESSURE, SYSTEM NO. 3 AUXILIARY 

PUMPS, TASK 29-00-00-860-805) (REMOVE HYDRAULIC PRESSURE, 

SYSTEM NO. 2 AUXILIARY PUMPS, TASK 29-00-00-860-807) (REMOVE 

HYDRAULIC PRESSURE, SYSTEM NO. 1 AUXILIARY PUMPS, TASK 29-00-

00-860-808) 

WARNING: TAG AND USE SAFETY CLIPS TO SAFETY THE CIRCUIT 

BREAKERS. IF THE CIRCUIT BREAKERS ARE NOT OPENED, 

TAGGED, AND SAFETIED, INJURY TO PERSONS AND DAMAGE 

TO EQUIPMENT CAN OCCUR. 

(4) Open these circuit breakers and install safety tags: 

AVIONICS, FLIGHT CONTROL DC BUS 1 

Row Col Number Name

C 8 B1-693 AUTO PITCH TRIM 1 

AVIONICS, MISC DC BUS 2 

Row Col Number Name

F 3 B1-507 PRIMARY HORIZ STAB TRIM 

OVERHEAD, RIGHT EMER DC BUS 

Row Col Number Name

E 26 B1-694 AUTO PITCH TRIM 2 

(5) Put a “DO NOT OPERATE” tag on the horizontal stabilizer suitcase handles on the 

control pedestal. 

(6) Remove the quill shaft and the right drive chain as follows: (Figure 4) 

(a) Remove and discard the lockwire from the head of the crossbolt (6). 

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SCI 27-8 - MD-11 HORIZONTAL STABILIZER ACTUATOR WEAR CHECK 

(cont’d) 

(b) Remove and discard the cotter pin (7) from the nut (8). 

CAUTION: HOLD THE QUILL SHAFT CORRECTLY WHEN YOU 

REMOVE THE BOLT. IF NOT, THE QUILL SHAFT WILL 

DROP. 

(c) Remove the nut (8), the washer (9), and the crossbolt (6) at the bottom of the 

quill shaft (10). 

(d) Remove the quill shaft (10). 

(e) Remove and discard the two clips (11) from the right turnbuckle (12). 

(f) Loosen the right turnbuckle (12) to release the tension. 

(g) Remove and discard the cotter pin (7) from the nut (14) at the right turnbuckle 

(12). 

(h) Remove the nut (14), the two washers (15), and the bolt (13) from the right 

turnbuckle (12). 

(i) Move the right turnbuckle (12) away from the idler sprocket (16). 

(j) Move the right drive chain idler sprocket (16) away from the drive chain (17). 

(k) Remove the drive chain (17) from the right acme nut sprocket (5). 

(7) Install the horizontal stabilizer test gage set as follows: (Figure 5) 

(a) Install the gage set torque adapter on the right acme nut sprocket (5). 

(b) Clean any grease or loose material from the surfaces of the left horizontal 

stabilizer attach lug and the left acme nut sprocket (4) where the gage set 

indicator probes will touch. 

(c) Install the two gage set indicators on the left actuator acme screw (2). 

1) Set the probe of one indicator against the surface of the acme nut sprocket 

(4). Move the indicator toward the sprocket until the probe is compressed 

approximately one half travel and the indicator needle is pointed up. 

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SCI 27-8 - MD-11 HORIZONTAL STABILIZER ACTUATOR WEAR CHECK 

(cont’d) 

2) Set the probe of the other indicator against the top surface of the horizontal 

stabilizer attach lug. Move the indicator toward the lug until the probe is 

compressed approximately one half travel and the indicator needle is 

pointed up. 

(d) Install the actuator restraint on the left acme nut sprocket (4) lugs and attach 

the end of the restraint to the adjacent structural beam with a clamp. 

(8) Do the tolerance test of the left horizontal stabilizer acme screw and nut as follows: 

(Figure 2) (Figure 5) 

Table 3 

STEP OPERATION VISUAL INSPECTION

1 Use the torque adapter to turn the right acme 

nut sprocket (5) clockwise and 

counterclockwise. 

Remove the tension on the 

right actuator. 

2 Turn the right acme nut sprocket (5) in a 

clockwise direction until the torque wrench 

shows 200 ft-lb (271.2 N·m) 

NOTE: The torque put to the actuator screw must be 200 ft-lb (271.2 N·m). The torque 

wrench must show 200 ft-lb (271.2 N·m) if the handle is installed parallel to the 

acme nut sprocket lugs. The torque wrench must show 155 ft-lb (210.3 N·m) if 

the handle is installed at a right angle to the acme nut sprocket lugs. 

3 Set the two gage set indicator dials to the zero 

position. 

4 Turn the right acme nut sprocket (5) in a 

counterclockwise direction until the torque 

wrench shows 200 ft-lb (271.2 N·m). 

5 Record the amount of indicator needle 

movement on each indicator. 

NOTE: The two indicator needles will move in opposite directions during the check. 

The amount of movement for the needle that moves in the positive direction 

can be read directly from the indicator scale. The amount of movement for the 

needle that moves in the negative direction must be calculated. 

6 Turn the right acme nut sprocket (5) in a 

clockwise direction until the torque wrench 

shows 200 ft-lb (271.2 N·m). 

The two gage set indicators 

should return to the zero 

position. 

7 Reset the indicators to the zero position, if 

necessary. 

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SCI 27-8 - MD-11 HORIZONTAL STABILIZER ACTUATOR WEAR CHECK 

(cont’d) 

STEP OPERATION VISUAL INSPECTION

8 Repeat steps 4 through 7 until you get three 

dimensions, one after the other, on each 

indicator that are no more than 0.003 inch 

(0.07 mm) apart, with a return to the zero 

reading each time. 

Record the applicable three 

dimensions from each 

indicator. 

9 Use the highest dimension recorded in step 8 

from each indicator to find out if the actuator 

wear is satisfactory. 

The highest indicator 

dimension on the acme nut 

sprocket must not be more 

than 0.068 inch (1.72 mm). 

If it is, replace the actuator. 

The highest indicator 

dimension on the stabilizer 

attach lug must not be more 

than 0.023 inch (0.58 mm). 

If it is, repair the connection 

between the actuator and 

the attach lug as necessary. 

10 Add the two indicator dimensions from step 9 

together. 

The sum of the two 

indicator dimensions must 

not be more than 0.080 inch 

(2.03 mm). If it is, replace 

the actuator and/or repair 

the connection between the 

actuator and the attach lug 

as necessary 

(9) Remove the horizontal stabilizer test gage set as follows: (Figure 5) 

(a) Remove the two gage set indicators from the left actuator acme screw (2). 

(b) Remove the clamp from the actuator restraint and remove the restraint from the 

left acme nut sprocket (4). 

(c) Remove the gage set torque adapter from the right acme nut sprocket (5). 

(10) Remove the left drive chain as follows: (Figure 4) 

(a) Remove and discard the two clips (11) from the left turnbuckle (12). 

SCI 27-8 - MD-11 HORIZONTAL STABILIZER ACTUATOR WEAR CHECK 

(cont’d) 

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(b) Loosen the left turnbuckle (12) to release the tension. 

(c) Remove and discard the cotter pin (7) from the nut (14) at the left turnbuckle 

(12). 

(d) Remove the nut (14), the two washers (15), and the bolt (13) from the left 

turnbuckle (12). 

(e) Move the left turnbuckle (12) away from the idler sprocket (16). 

(f) Move the left drive chain idler sprocket (16) away from the drive chain (17). 

(g) Remove the drive chain (17) from the left acme nut sprocket (4). 

(11) Install the horizontal stabilizer test gage set as follows: (Figure 5) 

(a) Install the gage set torque adapter onto the left acme nut sprocket (4). 

(b) Clean any grease or loose material from the surfaces of the right horizontal 

stabilizer attach lug and the right acme nut sprocket (5) where the gage set 

indicator probes will touch. 

(c) Install the two gage set indicators on the right actuator acme screw (3). 

1) Set the probe of one indicator against the surface of the acme nut sprocket 

(5). Move the indicator toward the sprocket until the probe is compressed 

approximately one half travel and the indicator needle is pointed up. 

2) Set the probe of the other indicator against the top surface of the horizontal 

stabilizer attach lug. Move the indicator toward the lug until the probe is 

compressed approximately one half travel and the indicator needle is 

pointed up. 

(d) Install the actuator restraint on the right acme nut sprocket (5) lugs and attach 

the end of the restraint to the adjacent structural beam with a clamp. 

(12) Do the tolerance test of the right horizontal stabilizer acme screw and nut as 

follows: (Figure 2) (Figure 5) 

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SCI 27-8 - MD-11 HORIZONTAL STABILIZER ACTUATOR WEAR CHECK 

(cont’d) 

Table 4 

STEP OPERATION VISUAL INSPECTION

1 Use the torque adapter to turn the left acme 

nut sprocket (5) clockwise and 

counterclockwise. 

Remove the tension on the 

left actuator. 

2 Turn the left acme nut sprocket (4) in a 

clockwise direction until the torque wrench 

shows 200 ft-lb (271.2 N·m) 

NOTE: The torque put to the actuator screw must be 200 ft-lb (271.2 N·m). The torque 

wrench must show 200 ft-lb (271.2 N·m) if the handle is installed parallel to the 

acme nut sprocket lugs. The torque wrench must show 155 ft-lb (210.2 N·m) if 

the handle is installed at a right angle to the acme nut sprocket lugs. 

3 Set the two gage set indicator dials to the zero 

position. 

4 Turn the left acme nut sprocket (5) in a 

counterclockwise direction until the torque 

wrench shows 200 ft-lb (271.2 N·m). 

5 Record the amount of indicator needle 

movement on each indicator. 

NOTE: The two indicator needles will move in opposite directions during the check. 

The amount of movement for the needle that moves in the positive direction can 

be read directly from the indicator scale. The amount of movement for the 

needle that moves in the negative direction must be calculated. 

6 Turn the left acme nut sprocket (4) in a 

clockwise direction until the torque wrench 

shows 200 ft-lb (271.2 N·m). 

The two gage set indicators 

should return to the zero 

position. 

7 Reset the indicators to the zero position, if 

necessary. 

8 Repeat steps 4 through 7 until you get three 

dimensions, one after the other, on each 

indicator that are no more than 0.003 inch 

(0.07 mm) apart, with a return to the zero 

reading each time. 

Record the applicable three 

dimensions from each 

indicator. 

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SCI 27-8 - MD-11 HORIZONTAL STABILIZER ACTUATOR WEAR CHECK 

(cont’d) 

STEP OPERATION VISUAL INSPECTION

9 Use the highest dimension recorded in step 8 

from each indicator to find out if the actuator 

wear is satisfactory. 

The highest indicator 

dimension on the acme nut 

sprocket must not be more 

than 0.068 inch (1.72 mm); 

if it is, replace the actuator. 

The highest indicator 

dimension on the stabilizer 

attach lug must not be more 

than 0.023 inch (0.58 mm); 

if it is, repair the connection 

between the actuator and 

the attach lug as necessary. 

10 Add the two indicator dimensions from step 9 

together. 

The sum of the two 

indicator dimensions must 

not be more than 0.080 inch 

(2.03 mm); if it is, replace 

the actuator and/or repair 

the connection between the 

actuator and the attach lug 

as necessary 

(13) Remove the horizontal stabilizer test gage set as follows: (Figure 5) 

(a) Remove the two gage set indicators from the right actuator acme screw (3). 

(b) Remove the clamp from the actuator restraint and remove the restraint from the 

right acme nut sprocket (5). 

(c) Remove the gage set torque adapter from the left acme nut sprocket (4). 

(14) Adjust the horizontal stabilizer actuators as follows: (Figure 2) (Figure 3) (Figure 

4) (Figure 5) 

(a) Make sure the drive chain idler sprockets (16) are free to move. 

(b) Make sure that each of the actuators (2) and (3) is installed at a height of 

30.29-30.69 in. (769.4-779.5 mm) as follows: 

1) To check the left actuator height dimension, measure from the bottom of 

the acme screw stop to the top of the acme nut. 

SCI 27-8 - MD-11 HORIZONTAL STABILIZER ACTUATOR WEAR CHECK 

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(cont’d) 

2) To check the right actuator height dimension, measure from the bottom of 

the acme screw serrations to the top of the acme nut. 

(c) For more precision, manually adjust the actuators (2) and (3) as follows: 

1) Make sure the difference between the two dimensions A and B is not more 

than 0.15 in. (3.8 mm). 

2) Make sure the difference between the two dimensions C and D is not more 

than 0.15 in. (3.8 mm). 

(d) Make sure the left and right acme nut grease fittings are each directly forward 

of their related acme screws. 

(e) Make sure the index marks on the acme nut sprockets (4) and (5) are each 

directly to the right of their related acme screws. 

(15) Install the two drive chains (17) as follows: (Figure 2) (Figure 4) 

(a) Make sure that the difference between the actuator height dimensions is no 

more than 0.40 inch (10.1 mm). 

(b) Install the two drive chains (17), on the acme nut sprockets (4), and (5), and 

the drive chain idler sprockets (16). 

(c) Make sure that any looseness in the chain is on the aft side of the acme nut 

sprockets (4) and (5). 

(d) Make sure that each master link is between a drive chain idler sprocket (16) 

and an acme nut sprocket (4) or (5). 

(e) Make sure that the right drive chain is installed in the two chain guards (18) 

and one chain guide (19). 

(f) Install the two turnbuckles (12) as follows: 

1) Move the drive chain idler sprockets (16) toward the drive chains (17) 

2) Move the turnbuckles (12) toward the idler sprockets (16). 

3) Install the two bolts (13), the four washers (15) and the two nuts (14). 

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SCI 27-8 - MD-11 HORIZONTAL STABILIZER ACTUATOR WEAR CHECK 

(cont’d) 

4) Safety the nuts with two cotter pins (7). 

5) Tighten the two turnbuckles (12) to a torque of 30-60 in-lb (3.4-6.7 N·m). 

While turning the turnbuckles, make sure that the acme nut sprockets (4) 

and (5) are free to turn so that the drive chain tensions can equalize. 

(16) Do a check of the horizontal stabilizer drive chain for the correct tension as 

follows: (Figure 2) (Figure 5) 

(a) Install the force indicator on the drive chain tension tester and put the toggle 

pad against the support structure. 

(b) With the pin against the left drive chain (17), loosen the thumb screw at the 

bottom of the scale. Adjust the pointer to align with zero on the scale, and 

tighten the thumb screw. 

(c) Put a forward load of 20 to 25 lb (9.1 to 11.3 Kg) on the drive chain between 

the acme nut sprocket (4) and the drive chain idler sprocket (16). If the chain 

moves more than 0.125 in. (3.17 mm), tighten the turnbuckle (12) to no more 

than 60 in-lb (6.7 N·m). 

(d) With the pin against the right drive chain (17), loosen the thumb screw at the 

bottom of the scale. Adjust the pointer to align with zero on the scale, and 

tighten the thumb screw. 

(e) Put a forward load of 20 to 25 lb (9.1 to 11.3 Kg) on the drive chain between 

the acme nut sprocket (5) and the drive chain idler sprocket (16). If the chain 

moves more than 0.125 in. (3.17 mm), tighten the turnbuckle (12) to no more 

than 60 in-lb (6.7 N·m). 

(17) Do a check of the horizontal stabilizer actuator dimensions as follows: (Figure 2) 

(a) Make sure that dimensions A and C are each 12.37 to 13.13 inches (314.1 to 

333.5 mm). 

(b) Calculate the difference between dimensions A and C. 

(c) If the difference is less than 0.40 inch (10.2 mm), go to step (18). 

(d) If the difference is 0.40 inch (10.2 mm) or more, do the steps that follow: 

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SCI 27-8 - MD-11 HORIZONTAL STABILIZER ACTUATOR WEAR CHECK 

(cont’d) 

1) Remove the drive chain (17) from the acme nut sprocket (4) or (5) that is 

farthest from the 12.75-inch (323.9-mm) dimension. 

2) Turn the farthest acme nut sprocket one tooth toward the 12.75-inch 

(323.9-mm) dimension, and repeat steps (15) through (17). 

(18) Install the four clips (11) in the two turnbuckles (12). (Figure 4) 

(19) Install the quill shaft (10) as follows: (Figure 4) (Figure 5) 

CAUTION: DO NOT TURN AN ACME NUT SPROCKET (4) OR (5) TO 

HELP INSTALL THE QUILL SHAFT WITH THE DRIVE 

CHAINS INSTALLED. TURNING AN ACME NUT SPROCKET 

WITH THE CHAINS INSTALLED CAN DAMAGE THE DRIVE 

ASSEMBLY FUSE PIN. 

(a) Install the spline torque adapter on the bottom of the drive assembly using the 

crossbolt holes. 

(b) Turn the spline torque adapter until the quill shaft (10) moves easily up into the 

gearbox. 

(c) Hold the quill shaft (10) in position and remove the spline torque adapter. 

(d) Install the crossbolt (6), the washer (9), and the nut (8). 

(e) Safety the nut (8) with a new cotter pin (7). 

(f) Safety the head of the crossbolt (6) with new 0.032-inch corrosion resistant 

steel lockwire. 

(20) Lubricate the drive chains. (LUBRICATION OF THE HORIZONTAL 

STABILIZER CONSTANT SECTION, TASK 12-24-09-600-801) 

(21) Remove the safety tags and close these circuit breakers: 

AVIONICS, FLIGHT CONTROL DC BUS 1 

Row Col Number Name

C 8 B1-693 AUTO PITCH TRIM 1 

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SCI 27-8 - MD-11 HORIZONTAL STABILIZER ACTUATOR WEAR CHECK 

(cont’d) 

AVIONICS, MISC DC BUS 2 

Row Col Number Name

F 3 B1-507 PRIMARY HORIZ STAB TRIM 

OVERHEAD, RIGHT EMER DC BUS 

Row Col Number Name

E 26 B1-694 AUTO PITCH TRIM 2 

(22) Remove the “DO NOT OPERATE” tag from the horizontal stabilizer suitcase 

handles on the control pedestal. 

(23) Do a test of the horizontal stabilizer range of movement. (FUNCTIONAL TEST 

OF THE HORIZONTAL STABILIZER RANGE OF MOVEMENT, TASK 27-40-

00-710-802) 

H. Lubricate the horizontal stabilizer actuators. (SCI 27-3 - MD-11 HORIZONTAL 

STABILIZER ACTUATOR LUBRICATION) 

I. Job Close-up - Horizontal Stabilizer Actuator Test 

(1) Remove all the tools and equipment from the work area. Make sure the area is 

clean. 

(2) Close this access panel: 

Number Name/Location

311AB AFT FUSELAGE 

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SCI 27-8 - MD-11 HORIZONTAL STABILIZER ACTUATOR WEAR CHECK 

(cont’d) 

Figure 1 

E 

LEGEND: 

1. PAIMAftY TAIM 

CONTROL VALVE 

CAG(IGOS) 082 27~891 
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SCI 27-8 - MD-11 HORIZONTAL STABILIZER ACTUATOR WEAR CHECK 

(cont’d) 

Figure 2 

E 

A AND B DIMENSIONS MUST BE 

EQUAL OR LESS THAN 0.15 in. 

(3.8 mm) DIFFERENCE. 

A 

LEGEND: 

2. LEFT ACTUATOR 

4. LEFT ACME NUT 

SPROCKET 

5. RIGHT ACME NUT 

SPROCKET 

16. DRIVE CHAIN IDLER 

SPROCKET 

CAGIIGDS) 

8 

AFT PRESSURE BULKHEAD 

NOTE: 

MEASURE DIMENSIONS 

A, B, C AND D FROM THE AFT 

FACE OF LIFTING LUGS 

TO THE AFT PRESSURE 

BULKHEAD 

C AND D DIMENSIONS MUST BE 

EQUAL OR LESS THAN 0.15 in. 

(3.8 mm) DIFFERENCE. 

5 t 

A 

MD-11 WEAR CHECK F2 
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SCI 27-8 - MD-11 HORIZONTAL STABILIZER ACTUATOR WEAR CHECK 

(cont’d) 

Figure 3 

E 

30.19-30.69 

l769.4-779.5mm) 

LEFT 

ACTUATOR 

BOTTOM OF 

ACME SCREW 

STOP 

LEFT ACME 

NUT SPROCKET 

VIEW A-A 

VIEW LOOKING FORWARD 

TO TOP OF NUT 

30.29-30.69 

!769.4-779.5m ml 

RIGHT 

ACTUATOR 

BOTTOM OF 

ACME SCREW 

SERRATIONS 

L RIGHTACME 

~·:>.L_j'-":j' /NUT SPROCKET 

r 

MD-11 WEAR CHECK F3 
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SCI 27-8 - MD-11 HORIZONTAL STABILIZER ACTUATOR WEAR CHECK 

(cont’d) 

Figure 4 

E 

LEGEND· · LEFT ACTUt.TOR 

4: ~~~~~~~~WJ~R S SPROCKET 

. ~~QA~CmE NUT 

S. CROSS BOLT 

7· COTIER Pll4 

8. NUT 

9· WASHER 

IO. QUILL SHAFT 

CAG(IGDS) 

II. CUP 

: ~~~~ UCKLE 

14. NUT 

1&. WASHER 

I S. ~:~v~C~~~IN IDLER 

17. DRIVE CHAIN 

18. CHAIN GUARD 

19. CHAIN GUIDE VIEW C 

NOTE: 

R GHT SIDE IS 

LEFT SIDE IS TSHOWN HE SAME. 

VIEW A 

DB2- 27-0893B 
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SCI 27-8 - MD-11 HORIZONTAL STABILIZER ACTUATOR WEAR CHECK 

(cont’d) 

Figure 5 

E 

RESTRAINT 

LEGEND· 

;· LEFT ~CTUATOR 

4 ~~~~~~~~U~JOR SPROCKET T 

5. RIGHT ACME N 

17. SPROCKET UT 

DRIVE CHAIN 

HORIZONTAL 

STABILIZER 

ATTACH LUG 

THUMB 

SCREW 

FORCE INDICATOR 

5 

DRIVE ASSEMBLY 

082-27-08948 

S000624463 1V2 
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SCI 27-8 - MD-11 HORIZONTAL STABILIZER ACTUATOR WEAR CHECK 

(cont’d) 

6. Is test equipment needed?

A list of the required fixtures, tools, and test and support equipment can be found in 

paragraph 2.A. of the wear check procedure in number 5 above. 

7. What is pass/fail criteria?

The pass/fail criteria can be found in paragraphs 2.G.(8) and 2.G.(12) of the actuator wear 

check procedure in number 5 above. 

8. What is SCI interval?

The actuator wear check shall be performed at intervals not to exceed 15,000 flight hours. 

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SCI 32-1 – TRIJET MAIN LANDING GEAR TRUCK BEAM PIVOT BOLT 

LUBRICATION 

(Airplanes that visit Short Wavelength Roughness Level 2 Runways) 

1. What model does this SCI apply to?

DC-10, MD-10, MD-11 series aircraft with visits to Short Wavelength Roughness (SWR) 

Level 2 Runways, as defined in the latest revisions of Service Letters DC-10-SL-32-

115, MD-10-SL-32-111 and MD-11-SL-32-120. 

2. What part or LRU is being checked?

Left and Right Main Landing Gear Truck Beam Pivot Joint – Pivot Bolt and Pivot Bolt 

Bushings 

3. What failure mode is being looked for?

A check for a failure mode does not apply. This SCI provides a lubrication procedure for 

the pivot bolt and pivot bolt bushings. 

4. How is it found?

Not Applicable 

5. What tasks are to be performed?

 

Lubricate the Truck Beam Pivot Bolt Attach Points on the Left and Right Main Landing 

Gear Strut and Main Landing Gear Truck per the AMM. 

 DC-10 AMM Reference 12-21-01 MD-10 AMM Reference 12-21-01 

 MD-11 AMM Reference 12-21 

6. Is test equipment needed?

No test equipment is required. 

7. What is pass/fail criteria?

This is a lubrication servicing procedure; pass/fail criteria do not apply. 

8. What is SCI interval?

The pivot bolts on both main landing gear truck beams are to be lubricated within 10 

cycles before and within 10 cycles after each visit to a SWR Level 2 runway. After 

completion of the lubrication within 10 cycles before and after each SWR Level 2 visit, 

return to MPD lubrication interval. 

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SCI 32-1 – TRIJET MAIN LANDING GEAR TRUCK BEAM PIVOT BOLT 

LUBRICATION 

(cont’d) 

If the pivot bolts are not lubricated within 10 cycles before a visit to a SWR Level 2 

runway, then lubricate the pivot bolts within 10 cycles after that SWR Level 2 runway 

visit. Repeat lubrication every 30 cycles thereafter until either the pivot bolt and 

bushings are inspected in accordance with SCI 32-2, or the pivot bolt and bushings are 

overhauled. 

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SCI 32-2 – TRIJET MAIN LANDING GEAR TRUCK BEAM PIVOT JOINT 

INSPECTION 

(Airplanes with Short Wavelength Roughness Level 2 Runway Visits since last MLG 

Overhaul or Pivot Joint Inspection) 

1. What model does this SCI apply to?

DC-10, MD-10, MD-11 series aircraft with visits to Short Wavelength Roughness (SWR) 

Level 2 Runways as defined in the latest revisions of Service Letters DC-10-SL-32-115, 

MD-10-SL-32-111 and MD-11-SL-32-120. 

2. What part or LRU is being checked?

Left and Right Main Landing Gear Truck Beam Pivot Joint – Pivot Bolt and Pivot Bolt 

Bushings 

3. What failure mode is being looked for?

This SCI checks the pivot bolt and bushing for wear and heat damage. A check is being 

performed to make certain that the pivot bolt and pivot bolt bushings have not exceeded 

their service limits. 

4. How is it found?

A detailed inspection of the pivot bolt and pivot bolt bushing. 

5. What tasks are to be performed?

 

Inspect the Pivot Bolt and Pivot Bolt Bushings 

1. Remove the left or right main gear pivot bolt for inspection 

a. Use AMM 32-12-01 “Removal/Installation Main Gear Truck Beam and Axle” for 

the DC-10 and MD-10 fleet to remove the pivot bolt for inspection. 

b. Use AMM 32-12-20 Task 32-12-20-000-801 “Removal of the Main Landing Gear 

Truck Assembly” for the MD-11 fleet to remove the pivot bolt for inspection. 

2. Do a detailed inspection of the pivot bolt and bushings 

a. Do a detailed inspection of the outer diameter of the pivot bolt. If cracks are 

found in the pivot bolt, or if the pivot bolt has bronze transfer, corrosion, or 

damage to the chrome plate, replace the pivot bolt with a new, overhauled, or 

serviceable pivot bolt before further flight. If bolt shank is less than 5.496" in 

diameter replace the pivot bolt with a new, overhauled, or serviceable pivot 

pin before further flight. 

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SCI 32-2 – TRIJET MAIN LANDING GEAR TRUCK BEAM PIVOT JOINT 

INSPECTION 

(cont’d) 

b Do a detailed inspection of the pivot bolt bushings in the main landing gear 

truck beam assembly and the strut assembly including checking for bushing 

rotation or migration. Verify that the bushings longitudinal lubrication groove 

is at the bottom of bore within +/- 5 degrees of vertical centerline at the 

bottom of bore. Verify all lubrication passages are clear and have the ability to 

flow grease. 

3. Return landing gear to serviceable condition 

a. Use AMM 32-12-01 “Removal/Installation Main Gear Truck Beam and Axle” 

for the DC-10 and MD-10 fleet 

b. Use AMM 32-12-20 Task 32-12-20-400-801 “Installation of the Main 

Landing Gear Truck Assembly” for the MD-11 fleet 

4. Repeat steps 1 through 3 for the opposite side main landing gear. 

6. Is test equipment needed?

No test equipment is required. 

7. What is pass/fail criteria?

Failure of the inspection is if cracks are found in the pivot bolt, or if the pivot bolt 

exhibits bronze transfer, corrosion, or damage to the chrome plate, bushings out of 

tolerance, else the inspection passes. 

8. What is SCI interval?

Inspection of the pivot bolts is to be done on or before 500 SWR Level 2 Runway 

landings or 24 months of first SWR Level 2 runway landing, which ever comes first, after 

MLG overhaul or Main Landing Gear Truck Beam Pivot Joint Inspection (SCI 32-2). 

 

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SCI 33-1 – MD-10 Map Light Assemblies 

1. What model does this SCI apply to?

MD-10 Series with P/N 2LA005916-XX installed 

2. What part or LRU is being checked?

A functional/inspection check of the Map Light Assemblies 

3. What failure mode is being looked for?

To detect broken light bulb housing and the resultant exposed power contactor. 

4. How is it found?

Perform inspection and replacement per 5 below. 

5. What tasks are to be performed?

 

Inspect per Aircraft Modification Letter MD-10-AML-33-101. 

6. Is test equipment needed?

No test equipment is required. 

7. What is pass/fail criteria?

Pass: No cracks, damaged or broken components (light bulb housing) or chafed/damaged 

map light assembly wires. 

8. What is SCI interval?

All intervals prior to, but not to exceed, 700 flight hours until terminating action is 

accomplished per MD-10-AML-33-101

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SCI 34-4 – FUNCTIONAL TEST OF THE CAPTAIN AND FIRST OFFICER’S 

ALTIMETER 

1. What model does this SCI apply to?

DC-10 series, MD-10 series, MD-11 series that are approved for flying Reduced Vertical 

Separation Minimum (RVSM) airspace. 

 

2. What part or LRU is being checked?

DC-10 andMD-11: Air Data Computer 

MD-10: Air Data Module 

 

3. What failure mode is being looked for?

The failure mode tested is transducer degradation of the air data system, which can cause 

erroneous altitude indication. 

 

4. How is it found?

 Perform inspection per 5 below. 

 

5. What tasks are to be performed?

 FUNCTIONAL TEST OF THE CAPTAIN’S AND FIRST OFFICER’S ALTIMETER 

1. Job Set-up: 

a. Open the circuit breakers referenced in the following AMM tasks: 

i. DC-10: ADJUSTMENT/TEST PITOT STATIC SYSTEMS 34-11-00 (Page 

Block 200). 

ii. MD-10: PITOT STATIC SYSTEM LEAK TEST 34-16-00 (P/B 500). 

iii. MD-11: FUNCTIONAL CHECK OF THE PITOT STATIC SYSTEM TASK 

34-11-00-720-801. 

b. Apply aircraft electrical power. 

i. DC-10: EXTERNAL POWER – DESCRIPTION AND OPERATION 24-40-

00 (P/B 001). 

ii. MD-10: EXTERNAL POWER – MAINTENANCE PRACTICES 24-40-00 

(P/B 200). 

iii. MD-11: ENERGIZE AIRCRAFT ELECTRICAL POWER SYSTEM TASK 

24-40-00-861-801. 

c. Connect the test equipment as follows: 

i. On the air data tester ATC control panel, place the ATC MODE SELECT 

switch in the STBY position. 

ii. DC-10 ONLY: 

1. Set the Captain’s and First officer’s static selector valve to NORM 

position. 

2. On the Overhead Panel, set the CADC switch to Norm. 

iii. MD-10: On the Captain’s and First Officer’s Gusset Panels, set the CADC 

switch light off. 

iv. MD-11: 

1. Set the Captain’s and First officer’s static selector valve to NORM 

position. 

2. On the Captain’s and First Officer’s Gusset Panels, set the CADC switch 

light off. 

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SCI 34-4 – FUNCTIONAL TEST OF THE CAPTAIN AND FIRST OFFICER’S 

ALTIMETER (cont’d)

WARNING: USE ONLY RED POLYESTER TAPE TO SEAL STATIC 

PORTS. IF THE HOLES BECOME CLOGGED WITH TAPE 

RESIDUE, INCORRECT AIRSPEED-SENSING 

ANDALTITUDE-SENSING SIGNALS CAN OCCUR. THIS 

CAN CAUSE DANGEROUS FLIGHT CONDITIONS. 

v. Seal the captain’s and first officer’s pitot tube drain holes with red polyester 

tape or other suitable device. 

vi. Connect the air data tester to the captain’s and first officer’s pitot tube. 

vii. Connect the air data tester to the captain’s and first officer’s static ports using 

suitable adapter. 

viii. Seal the opposite side static ports using red polyester tape or other suitable 

device. 

 

d. Set the Captain’s and First Officer’s BARO set to 29.92 in/Hg (1013.21 mBar). 

 

WARNING: MAKE SURE ALL PERSONS AND EQUIPMENT ARE CLEAR OF 

THE AREAS AROUND THE CONTROL SURFACES. THE TEST 

CAN CAUSE THE AIRCRAFT CONTROL SURFACES TO MOVE. 

SUDDEN MOVEMENT OF THE CONTROL SURFACES CAN 

CAUSE INJURY TO PERSONS AND DAMAGE TO EQUIPMENT. 

 

CAUTION: MAKE SURE THE AIR DATA TESTER OPERATES CORRECTLY. 

IF IT DOES NOT OPERATE CORRECTLY, IT CAN CAUSE 

DAMAGE TO THE INSTRUMENTATION SENSOR DEVICES. 

 

CAUTION: WHEN YOU CHANGE ALTITUDE, DO NOT LET THE RATE OF 

CHANGE BE MORE THAN 6,000 FEET PER MINUTE. WHEN YOU 

CHANGE AIRSPEED, DO NOT LET THE RATE OF CHANGE BE 

MORE THAN 100 KNOTS PER MINUTE. DO NOT SUDDENLY 

RELEASE PRESSURE TO THE ATMOSPHERE FROM THE 

PITOT/STATIC LINES WHILE THE AIR DATA TESTER IS 

CONNECTED. DO NOT LET THE STATIC PRESSURE BE MORE 

THAN THE PITOT PRESSURE. THIS WILL HELP PREVENT 

DAMAGE TO THE EQUIPMENT. 

 

2. Do the functional test of the Captain’s and First Officer’s Altimeter as follows: 

a. On the air data tester, adjust the altitude to 41,000 feet (12,497 m). 

b. On the air data tester, adjust the airspeed to 105 knots. 

c. On the captain’s instrument panel: 

i. Captain’s altitude requirements: 

1. DC-10 and MD-10: The altitude shown on the captain’s altimeter must be 

41,000 feet (12,497 meters) ± 75 feet (23 meters). 

2. MD-11: The altitude shown on the captain’s altimeter must 40,955 feet 

(12,483 meters) ± 75 feet (23 meters). 

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SCI 34-4 – FUNCTIONAL TEST OF THE CAPTAIN AND FIRST OFFICER’S 

ALTIMETER (cont’d)

ii. Captain’s airspeed requirements: 

1. DC-10 and MD-10: The airspeed shown on the captain’s airspeed 

indication must be 105 knots ± 4 knots. 

2. MD-11: The airspeed shown on the captain’s airspeed indication must be 

104 knots ± 4 knots. 

d. On the first officer’s instrument panel: 

i. First Officer’s altitude requirements: 

1. DC-10 and MD-10: The altitude shown on the First Officer’s altimeter 

must be 41,000 feet (12,497 meters) ± 75 feet (23 meters). 

2. MD-11: The altitude shown on the First Officer’s altimeter must be 

40,955 feet (12,483 meters) ± 75 feet (23 meters). 

ii. First Officer’s airspeed requirements: 

1. DC-10 and MD-10: The airspeed shown on the First Officer’s airspeed 

indication must be 105 knots ± 4 knots. 

2. MD-11: The airspeed shown on the First Officer’s airspeed indication 

must be 104 knots ± 4 knots. 

3. Job Close-up: 

a. Remove the test equipment as follows: 

i. Disconnect the air data tester from the captain’s pitot tube and captain’s static 

port. 

ii. Remove tape from the captain’s pitot tube drain holes and static port. 

b. Remove all the tools and equipment from the work area. Make sure the area is 

clean. 

c. Remove the safety tags and close these circuit breakers opened in Job Set-up. 

d. Remove external power from the aircraft. 

i. DC-10: EXTERNAL POWER – DESCRIPTION AND OPERATION 24-40-

00 (P/B 001). 

ii. MD-10: EXTERNAL POWER – MAINTENANCE PRACTICES 24-40-00 

(P/B 200). 

iii. MD-11: REMOVE ELECTRICAL POWER TASK 24-40-00-862-801. 

 

6. Is test equipment needed? 

 Tester, Air Data: must have a maximum altitude tolerance of +/-15ft (5 m) at 41,000ft 

(12,497 m). 

 Adapter, Static Port 

 Adapter, Pitot Head 

 Tape - Polyester, Red, Silicone Adhesive: Specification DPM 850-24 or equivalent 

 

7. What is pass/fail criteria? 

Pass Criteria: 

 Captain’s altitude requirements, 

o DC-10 and MD-10: The altitude shown on the captain’s altimeter must be 

41,000 feet (12,497 meters) ± 75 feet (23 meters) at 41,000 feet (12,497 

meters). 

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SCI 34-4 – FUNCTIONAL TEST OF THE CAPTAIN AND FIRST OFFICER’S 

ALTIMETER (cont’d)

o MD-11: The altitude shown on the captain’s altimeter must be 40,955 feet 

(12,483 meters) ± 75 feet (23 meters) at 41,000 feet (12,497 meters). 

 Captain’s airspeed requirements, 

o DC-10 and MD-10: The airspeed shown on the captain’s airspeed indication 

must be 105 knots ± 4 knots at 105 knots. 

o MD-11: The airspeed shown on the captain’s airspeed indication must be 104 

knots ± 4 knots at 105 knots. 

 First Officer’s altitude requirements, 

o DC-10 and MD-10: The altitude shown on the First Officer’s altimeter must 

be 41,000 feet (12,497 meters) ± 75 feet (23 meters) at 41,000 feet (12,497 

meters). 

o MD-11: The altitude shown on the First Officer’s altimeter must be 40,955 

feet (12,483 meters) ± 75 feet (23 meters) at 41,000 feet (12,497 meters). 

 First Officer’s airspeed requirements, 

o DC-10 and MD-10: The airspeed shown on the First Officer’s airspeed 

indication must be 105 knots ± 4 knots at 105 knots. 

o MD-11: The airspeed shown on the First Officer’s airspeed indication must be 

104 knots ± 4 knots at 105 knots. 

Fail: Is any of the altitude and airspeed requirements are outside the tolerances listed in 

the pass criteria. 

 

8. What is SCI interval? 

MD-10/MD-11: Intervals not to exceed 48 months. 

DC-10: Intervals not to exceed 24 months. 

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Page B1

Appendix B 

Critical Design Configuration Control Limitations (CDCCLs) 
MDC-02K1003 

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TRIJET CRITICAL DESIGN CONFIGURATION CONTROL LIMITATIONS 

For some trijet system functions, for compliance with SFAR 88 and Advisory Circular (AC) 

25.981-1B, limitations for certain SFAR88 design configurations are required using AC 25-19 

“Certification Maintenance Requirements (CMRs)” methodology as a guide. 

Critical Design Configuration Control Limitations (CDCCLs) are a means of notifying the FAA, 

operators, and maintenance facilities of certain design configuration aspects that cannot be 

changed without violating the design intent, potentially making the airplane non-compliant with 

FAR 25.981(b). Therefore, these configuration aspects must be controlled such that they remain 

in the configuration as specified in each CDCCL. 

The following CDCCLs are features that Boeing has identified as not obvious or intuitive that a 

change could impact safety. This list is not inclusive of every potential change or feature that is 

possible. For example, changing a circuit breaker to a higher current rating is not covered here 

because such a change obviously needs to be evaluated for impact to the circuit it protects. 

Changing a wire to a smaller gauge would have to be evaluated to determine if it could carry the 

required currents. However, a change to a larger wire gauge has in the past been allowed 

without specific assessment, but this could increase the chance of a tank wall burn through so it 

is identified as a CDCCL. Any change or repair to any part of the aircraft not performed in 

accordance with OEM published data must be assessed by the modifier for safety and 

certification impact per the FARs; any changes or repairs performed in accordance with OEM 

published date prior to the CDCCL compliance time do not require reassessment. This list is 

only an aid to the operator and to the FAA in evaluating future fuel system related repairs and 

changes for potential tank ignition risk. 

The terms of the appropriate trijet Type Certificate are only valid when the design configuration 

aspects specified by these CDCCLs are maintained as stated. The configuration control 

limitations are mandatory and cannot be changed or deleted without the approval of FAA 

Engineering of the Los Angeles Aircraft Certification Office (LA-ACO). 

SFAR88 established requirements for CDCCLs; it includes an implementation schedule for 

changes to the operator’s control documents to manage compliance with these limitations. 

While each CDCCL is included in this report, it is required that each CDCCL also be included in 

an appropriate document where it will be visible to airline personnel; therefore each CDCCL 

configuration control information must be included in appropriate Operator's maintenance 

documentation. 

All maintenance and repair instructions provided by Boeing have been updated where required to 

ensure compatibility with these design limitations. 

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BOEING PROPRIETARY INFORMATION 

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Page B3

Each CDCCL specified herein includes the name of the system in which the CDCCL is needed, 

and the following information: 

1. What model trijet does this CDCCL apply to? 

2. What part, LRU or system is the CDCCL levied against? 

3. What characteristic of the design configuration for this item must be retained under control of 

this Limitation, and why? 

4. What is the specific Limitation? 

5. Were all applicable aircraft in compliance with this CDCCL at delivery from the Original 

Equipment Manufacturer (OEM)? If not, is there an applicable Service Bulletin or Service 

Rework package required for some aircraft? 

6. When does this CDCCL become effective? 
MDC-02K1003 

Revision H 

BOEING PROPRIETARY INFORMATION 

Copyright © - The Boeing Company - Unpublished Work 

Page B4

CDCCL 20-1 - Trijet Repair Wire Gauges 

1. What trijet model does this CDCCL apply to? 

DC-10 Series 

MD-10 Series 

MD-11 Series 

2. What part, LRU or system is the CDCCL levied against? 

Any repair wiring used inside or within 6” of the fuel tanks and fuel pipes. 

3. What characteristic of the design configuration for this item must be retained under 

control of this Limitation, and why? 

Adverse excessive temperatures that could result from wire arcing events are 

characterized for a limited, known set of OEM-approved wire gauges. 

4. What is the specific Limitation? 

Any repair wiring inside or within 6” of the fuel tanks and fuel pipes must use the same 

wire gauge as the wire being replaced. 

5. Were all applicable aircraft in compliance with this CDCCL at delivery from the 

OEM? If not, is there an applicable Service Bulletin or Service Rework package 

required for some aircraft? 

DC-10 Series All airplane type designs comply. 

MD-10 Series All airplane type designs comply 

MD-11 Series All airplane type designs comply 

6. When does this CDCCL become effective? 

This CDCCL becomes effective for all repairs performed after August 1, 2006. 

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Revision A 

BOEING PROPRIETARY INFORMATION 

Copyright © - The Boeing Company - Unpublished Work 

Page B5

CDCCL 20-2 - Trijet FQIS Wire Isolation 

1. What trijet model does this CDCCL apply to? 

DC-10 Series 

MD-10 Series 

MD-11 Series 

2. What part, LRU or system is the CDCCL levied against? 

Fuel Quantity Indication System (FQIS) wiring. 

3. What characteristic of the design configuration for this item must be retained under 

control of this Limitation, and why? 

FQIS wires must be isolated or separated from other aircraft wiring, to prevent chafing 

that can lead to shorting to an incompatible power source. 

4. What is the specific Limitation? 

FQIS wires (as defined below) must maintain isolation from other aircraft wiring or have 

an integral physical barrier (as part of the approved FQIS wire construction). 

FQIS Wire Bundle Definition

DC-10/KC-10/KDC-10 - Master Indicator to Tank entry points 

MD-10 – Fuel Quantity Processor Unit (FQPU) to Tank entry points 

MD-11 – Standard Electronic Module (SEM) to Tank entry points 

5. Were all applicable aircraft in compliance with this CDCCL at delivery from the 

OEM? If not, is there an applicable Service Bulletin or Service Rework package 

required for some aircraft? 

DC-10 Series All airplane type designs comply. 

MD-10 Series All airplane type designs comply. 

MD-11 Series All airplane type designs comply. 

6. When does this CDCCL become effective? 

This CDCCL becomes effective for all repairs performed after August 1, 2006. 
MDC-02K1003 

Revision J 

BOEING PROPRIETARY INFORMATION 

Copyright © - The Boeing Company - Unpublished Work 

Page B6

CDCCL 20-3 – Trijet Fuel Pump Conduit Sleeves 

1. What trijet model does this CDCCL apply to? 

DC-10 Series 

MD-10 Series 

MD-11 Series 

2. What part, LRU or system is the CDCCL levied against? 

Fuel pump conduit. 

3. What characteristic of the design configuration for this item must be retained under 

control of this Limitation, and why? 

Teflon® hoses are to be installed inside the fuel pump conduits to provide wire protection 

from chafing and shorting to the conduit wall. 

4. What is the specific Limitation? 

Teflon® hoses must be installed as a liner in metal fuel pump conduits per OEM 

drawings or AMM or SWPM or any combination of those. 

5. Were all applicable aircraft in compliance with this CDCCL at delivery from the 

OEM? If not, is there an applicable Service Bulletin or Service Rework package 

required for some aircraft? 

DC-10 Series No, not all DC-10 type designs complied at time of delivery; see 

below for Service Bulletin information: 

Service Bulletin DC10-24-123 revision 2 Change Notice 1 dated 

8/21/1984 or later 

DC-10 Series 10, 15, 30, 40 and KC-10A 

Service Rework Drawing WNP7003 

Installs Teflon® liner around wires in fuel boost pump conduits. 

Service Bulletin DC10-24-128 revision New dated 1/19/1984 or 

later 

DC-10 Series 30 

Service Rework Drawing WGP7004 

Installs Teflon® liner around wires in fuel boost pump conduits for 

Aft Supplemental Fuel Tank. 

DC-10 Series 10, 15, 30, 40 and KC-10A may install alternate 

conduit tubing with Teflon® liners installed per Service Rework 

Drawing SR10280079 as an alternate method of compliance to 

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BOEING PROPRIETARY INFORMATION 

Copyright © - The Boeing Company - Unpublished Work 

Page B7

CDCCL 20-3 – Trijet Fuel Pump Conduit Sleeves 

(cont’d) 

DC-10-24-123 and DC10-24-128 service bulletins. 

MD-10 Series All airplane type designs comply. 

MD-11 Series All airplane type designs comply. 

6. When does this CDCCL become effective? 

This CDCCL becomes effective for all repairs performed after August 1, 2006. 

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BOEING PROPRIETARY INFORMATION 

Copyright © - The Boeing Company - Unpublished Work 

Page B8

CDCCL 20-4 - Trijet In-Tank Wire Splices 

1. What trijet model does this CDCCL apply to? 

DC-10 Series 

MD-10 Series 

MD-11 Series 

2. What part, LRU or system is the CDCCL levied against? 

Any wiring inside the fuel tanks, including those routed in conduit located inside the fuel 

tank. 

 Wiring going to AC and DC fuel pumps. 

 Wiring belonging to the fuel quantity gauging system (FQGS). 

 Wiring going to fuel high-level and low-level float switches (as applicable). 

This does not include wiring inside a LRU. 

3. What characteristic of the design configuration for this item must be retained under 

control of this Limitation, and why? 

Wiring inside fuel tanks shall not contain splices, including wiring within in-tank 

conduits. 

Splices may allow fuel penetration to the conductors of the spliced wires. 

A deteriorated wire splice could result in a high resistance electrical path, higher than 

allowable wire temperatures, arcing and/or breach of the conduit assembly. 

Improper shielding/insulation at the splice could result in arcing to the conduit and breach 

of the conduit assembly. 

4. What is the specific Limitation? 

Splices of any type, including crimp or solder type, shall not be allowed on wires in the 

fuel tank or on wires inside conduits that are in the fuel tank. 

5. Were all applicable aircraft in compliance with this CDCCL at delivery from the 

OEM? If not, is there an applicable Service Bulletin or Service Rework package 

required for some aircraft? 

DC-10 Series All airplane type designs comply. 

MD-10 Series All airplane type designs comply. 

MD-11 Series All airplane type designs comply. 
MDC-02K1003 

Revision A 

BOEING PROPRIETARY INFORMATION 

Copyright © - The Boeing Company - Unpublished Work 

Page B9

CDCCL 20-4 - Trijet In-Tank Wire Splices 

(cont’d) 

6. When does this CDCCL become effective? 

This CDCCL becomes effective for all repairs performed after August 1, 2006. 
MDC-02K1003 

Revision A 

BOEING PROPRIETARY INFORMATION 

Copyright © - The Boeing Company - Unpublished Work 

Page B10

CDCCL 20-5 – Trijet Repair Wire Types 

1. What trijet model does this CDCCL apply to? 

DC-10 Series 

MD-10 Series 

MD-11 Series 

2. What part, LRU or system is the CDCCL levied against? 

Any repair wiring used inside or within 6” of the fuel tanks and fuel pipes. 

3. What characteristic of the design configuration for this item must be retained under 

control of this Limitation, and why? 

Adverse excessive temperatures that could result from wire arcing events are 

characterized for a limited, known set of OEM-previously approved wire types. 

4. What is the specific Limitation? 

Any repair wiring used inside or within 6” of the fuel tanks and fuel pipes cannot use any 

of the following wire types: 

1. DES-SM2006 (PVC/Nylon) 

2. 7484444 (“Quad 4”, PVC/Fiberglass/Nylon) 

3. 7616964 (PVC/Nylon & PVC/Fiberglass/Nylon) 

4. 7706560 (MIL-W-81044/9, XL-Polyolefin/XL-Kynar) 

5. 7891145 (was Poly-X, then later was Stilan) 

6. BXS7007 (Aromatic Polyimide) 

5. Were all applicable aircraft in compliance with this CDCCL at delivery from the 

OEM? If not, is there an applicable Service Bulletin or Service Rework package 

required for some aircraft? 

DC-10 Series Aircraft as originally built with previously approved wire types are 

acceptable. New repairs should only be made with OEM approved 

wire types. 

MD-10 Series Aircraft as originally built with previously approved wire types are 

acceptable. New repairs should only be made with OEM approved 

wire types. 

MD-11 Series Aircraft as originally built with previously approved wire types are 

acceptable. New repairs should only be made with OEM approved 

wire types. 
MDC-02K1003 

Revision A 

BOEING PROPRIETARY INFORMATION 

Copyright © - The Boeing Company - Unpublished Work 

Page B11

CDCCL 20-5 – Trijet Repair Wire Types 

(cont’d) 

6. When does this CDCCL become effective? 

This CDCCL becomes effective for all repairs performed after August 1, 2006. 
MDC-02K1003 

Revision H 

BOEING PROPRIETARY INFORMATION 

Copyright © - The Boeing Company - Unpublished Work 

Page B12

CDCCL 20-6 - Trijet Wire Installations 

1. What trijet model does this CDCCL apply to? 

DC-10 Series 

MD-10 Series 

MD-11 Series 

2. What part, LRU or system is the CDCCL levied against? 

Any wiring used within 6” of fuel tanks and fuel pipes. 

3. What characteristic of the design configuration for this item must be retained under 

control of this Limitation, and why? 

Adverse excessive temperatures that could result from wire arcing events are 

characterized for a limited, known set of OEM-approved wire distance to the fuel tank 

walls or pipes. 

4. What is the specific Limitation? 

Repair of wiring within 6” of fuel tanks and fuel pipes must use existing wire routing and 

clipping established per OEM-approved wire installation or maintain wire clearances as 

prescribed in the applicable sections of SWPM 20-00-06 and/or SWPM 20-10-01. 

5. Were all applicable aircraft in compliance with this CDCCL at delivery from the 

OEM? If not, is there an applicable Service Bulletin or Service Rework package 

required for some aircraft? 

DC-10 Series All aircraft type designs comply. 

MD-10 Series All aircraft type designs comply. 

MD-11 Series All aircraft type designs comply. 

6. When does this CDCCL become effective? 

This CDCCL becomes effective for all repairs performed after August 1, 2006. 

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Copyright © - The Boeing Company - Unpublished Work 

Page B13

CDCCL 20-7 - Trijet Prohibition of Power Feeder Splices in Areas Above Fuel Tanks 

1. What trijet model does this CDCCL apply to? 

DC-10 Series 

MD-10 Series 

MD-11 Series 

2. What part, LRU or system is the CDCCL levied against? 

Power feeders above any fuel tank. 

Power feeders are defined as any wire 10 gauge and larger (10, 8, 6, 4, 2, 0, 00, 000 and 

0000 wire gauges). 

3. What characteristic of the design configuration for this item must be retained under 

control of this Limitation, and why? 

Maintain wire continuity over fuel tanks without breaks. This will prevent adverse 

temperature effects on the fuel tank due to a potential splice failure. 

4. What is the specific Limitation? 

Power Feeders above any fuel tank shall be maintained without splices. Any needed 

repair splice need to be implemented at a location at least 3 feet or 2 wire supports 

(whichever is further) from the fuel tank boundaries. 

5. Were all applicable aircraft in compliance with this CDCCL at delivery from the 

OEM? If not, is there an applicable Service Bulletin or Service Rework package 

required for some aircraft? 

DC-10 Series All aircraft type designs comply. 

MD-10 Series All aircraft type designs comply. 

MD-11 Series All aircraft type designs comply. 

6. When does this CDCCL become effective? 

This CDCCL becomes effective for all repairs performed after August 1, 2006. 
MDC-02K1003 

Revision H 

BOEING PROPRIETARY INFORMATION 

Copyright © - The Boeing Company - Unpublished Work 

Page B14

CDCCL 20-8 - Trijet Fuel Tank Access Door Bonding 

1. What trijet model does this CDCCL apply to? 

DC-10 Series 

MD-10 Series 

MD-11 Series 

2. What part, LRU or system, is the CDCCL levied against? 

All fuel tank access doors. 

3. What characteristic of the design configuration for this item must be retained under 

control of this Limitation, and why? 

Electrical current paths are defined by the installation and bonding processes in the 

relevant OEM fuel tank access door and access door installation design drawings. The 

paths are intended to conduct lightning current flowing along the skin, across the doors, 

or to disperse lightning current from an attachment point on an attach bolt, or a door, to 

the skin without arcing/sparking. The effectiveness of the conductive paths depends on 

specific surface treatments, sealants, sealing procedures, seals, o-rings, fastener types, 

materials, conductive rubstrips, interference fit fasteners, and coatings. 

The non-conductive features of the door installation shall also be maintained as they help 

to direct current flow to the conductive path. This includes anodizing, priming and 

sealing, as well as the seals (a type of rubber O-ring) on the door and the dome nuts. 

Departing from the OEM designed electrical current path across different interfaces could 

create hazardous ignition sources inside the tank. 

4. What is the specific Limitation? 

The conductive and non conductive path design which includes specific surface 

treatments, sealants, sealing procedures, seals, o-rings, fastener types, materials, 

conductive rubstrips, interference fit fasteners, and coatings must be maintained per OEM 

design data which includes Boeing design drawings or the Boeing SRM or the Boeing 

AMM or Boeing approved repairs or any combination of those. 

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Revision H 

BOEING PROPRIETARY INFORMATION 

Copyright © - The Boeing Company - Unpublished Work 

Page B15

CDCCL 20-8 - Trijet Fuel Tank Access Door Bonding 

(cont’d) 

5. Were all applicable aircraft in compliance with this CDCCL at delivery from the 

OEM? If not, is there an applicable Service Bulletin or Service Rework package 

required for some aircraft? 

DC-10 Series All aircraft type designs comply. 

MD-10 Series All aircraft type designs comply. 

MD-11 Series All aircraft type designs comply. All aircraft upgraded to expand 

fuel tank capacity in accordance with Service Bulletin MD11-28-

018 revision 2 dated 3/26/1993 or later also comply. 

6. When does this CDCCL become effective? 

This CDCCL becomes effective for all repairs performed after August 1, 2006. 
MDC-02K1003 

Revision G 

BOEING PROPRIETARY INFORMATION 

Copyright © - The Boeing Company - Unpublished Work 

Page B16

CDCCL 20-9 – Trijet Wing Root Area Lightning Protection 

1. What trijet model does this CDCCL apply to? 

DC-10 Series 

MD-10 Series 

MD-11 Series 

2. What part, LRU or system is the CDCCL levied against? 

Sheet metal or braided electrical bonding conductors or straps in the wing leading edge area 

of the wing fillet connecting the ribs together and connecting the ribs to the fuselage. Also 

the metal overbraid shielding on the wire harnesses in the wing root area for the MD-10, 

MD-11, and early DC-10 FQGS. 

3. What characteristic of the design configuration for this item must be retained under 

control of this Limitation, and why? 

a. The intense electromagnetic field created by lightning current in the wing root area is 

attenuated by a number of metallic straps between the wing forward section (leading 

edge) at the most inboard rib and the fuselage. The wire harnesses in the wing root area 

are further protected with metal overbraid shields, grounded at both ends. These straps 

and shields provide lightning protection to the aircraft fuel system equipment interfaced 

with the wires spanning the wing root area. 

b. The straps must be continuous and unbroken, the low-resistance electrical bonds at the 

two ends must be maintained. The overbraid must be continuous and undamaged by cuts, 

fraying, corrosion or other defects. The low-resistance bonds or grounds must be 

maintained at both ends of the overbraid for it to be effective. 

c. All replacement wires in the wing-root area require lightning protection to prevent 

induced voltages and currents from contamination and threatening other aircraft systems 

in common wire harnesses inside the aircraft and wing. 

4. What is the specific Limitation? 

Do not alter or remove the wing root lightning protection straps and wire overbraids and 

shields. Any replacement wires introduced in this area must also be shielded/overbraided in 

the same manner with the overbraids grounded at both ends. 
MDC-02K1003 

Revision G 

BOEING PROPRIETARY INFORMATION 

Copyright © - The Boeing Company - Unpublished Work 

Page B17

CDCCL 20-9 – Trijet Wing Root Area Shielding 

(cont’d) 

5. Were all applicable aircraft in compliance with this CDCCL at delivery from the 

OEM? If not, is there an applicable Service Bulletin or Service Rework package 

required for some aircraft? 

- Early DC-10s did not comply. Bonding straps and FQGS overbraid were installed by 

service bulletin: 

 SB DC10-28-062 R1 dated 10/16/1981 or later (installs conduit on fuel probe 

wires in wing root) 

 SB DC10-53-109 R4 dated 10/7/1992 or later (installs bonding straps for 

extended fillet) 

 SB DC10-53-111 R3 dated 8/24/1992 or later (installs bonding straps for 

conventional fillet) 

 SB DC10-28-262 Rev 1 or later (installs “Roundit 2000NX EMI” (DMS 2379, 

Type 5, Class 4) sleeving on fuel probe wires in wing root, alternate to SB DC10-28-062 R1) 

- Later trijets had the bonding straps, and/or overbraid installed at the factory as originally 

delivered. 

6. When does this CDCCL become effective? 

This CDCCL becomes effective for all repairs performed after August 1, 2006. 

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Revision H 

BOEING PROPRIETARY INFORMATION 

Copyright © - The Boeing Company - Unpublished Work 

Page B18

CDCCL 20-10 – Trijet Fuel Tank Structural Design 

1. What trijet model does this CDCCL apply to? 

DC-10 Series 

MD-10 Series 

MD-11 Series 

2. What part, LRU or system is the CDCCL levied against? 

Fuel tank structure. 

3. What characteristic of the design configuration for this item must be retained under 

control of this Limitation, and why? 

The electrical bonding path must be maintained at all tank penetrations and applicable 

equipment mounting brackets internal and external to the tank. Specifically the types of 

surface preparation prior to assembly and types of fasteners used must assure that all 

mechanical joints and penetrations can handle the lightning currents at the respective 

locations. The non-conductive features (anodizing, priming, painting and sealing) also 

must be preserved, since they could be part of the design to direct current to the conductive 

parts, prevent arcing at specific locations or contain minor arcing. 

4. What is the specific Limitation? 

 The conductive and non conductive path design which includes specific surface 

treatments, sealants, sealing procedures, fastener types, and coatings must be maintained 

per OEM design data which includes Boeing design drawings or the Boeing SRM or the 

Boeing AMM or Boeing approved repairs or any combination of those. 

5. Were all applicable aircraft in compliance with this CDCCL at delivery from the 

OEM? If not, is there an applicable Service Bulletin or Service Rework package 

required for some aircraft? 

DC-10 Series All aircraft type designs comply. 

MD-10 Series All aircraft type designs comply. 

MD-11 Series All aircraft type designs comply. 

6. When does this CDCCL become effective? 

This CDCCL becomes effective for all repairs performed after August 1, 2006. 

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MDC-02K1003 

Revision H 

BOEING PROPRIETARY INFORMATION 

Copyright © - The Boeing Company - Unpublished Work 

Page B19

CDCCL 20-11 – MD-11 Maintenance of Winglet Bonds 

1. What trijet model does this CDCCL apply to? 

MD-11 Series with the expanded wing fuel tank 

2. What part, LRU or system is the CDCCL levied against? 

The electrical bonding provisions at the interfaces, bolts, and fasteners where the winglet 

structure is attached to the wing. 

3. What characteristic of the design configuration for this item must be retained under 

control of this Limitation, and why? 

Maintenance of the original bonding design, and maintenance of the sealing and 

encapsulation to prevent spark generation or release into the fuel tank in case of lightning 

strikes to the winglet. 

4. What is the specific Limitation? 

The 17 bolts, attaching the winglet, that enter the fuel vapor area, shall be installed with 

the proper electrical bonding under the heads and nuts per the OEM design. The exposed 

fasteners shall be encapsulated with sealant after tightening per OEM design. 

The electrical bonding in the countersinks for the fasteners on the strap attaching the 

winglet skin to the wing skin at the leading edge and trailing edge shall be maintained in 

the OEM configuration. 

The conductive and non conductive path design which includes specific surface 

treatments, sealants, sealing procedures, seals, o-rings, fastener types, materials, 

conductive rubstrips, interference fit fasteners, and coatings must be maintained per OEM 

design data which includes Boeing design drawings or the Boeing AMM or Boeing SRM 

Boeing approved repairs or any combination of those. 

During and after assembly, the type-design sealant applications shall be observed. The 

fastener areas shall be encapsulated with sealant where required. 

5. Were all applicable aircraft in compliance with this CDCCL at delivery from the 

OEM? If not, is there an applicable Service Bulletin or Service Rework package 

required for some aircraft? 

MD-11 Series All aircraft comply as originally delivered. All aircraft upgraded 

to expand fuel tank capacity in accordance with Service Bulletin 

MD11-28-018 revision 2 dated 3/26/1993 or later also comply. 

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Revision H 

BOEING PROPRIETARY INFORMATION 

Copyright © - The Boeing Company - Unpublished Work 

Page B20

CDCCL 20-11 – MD-11 Maintenance of Winglet Bonds 

(cont’d) 

6. When does this CDCCL become effective? 

This CDCCL becomes effective for all repairs performed after August 1, 2006. 
MDC-02K1003 

Revision H 

BOEING PROPRIETARY INFORMATION 

Copyright © - The Boeing Company - Unpublished Work 

Page B21

CDCCL 20-12 – MD-11 Maintenance of Tail Tank FQIS Wiring Overbraid 

1. What trijet model does this CDCCL apply to? 

MD-11 Series 

2. What part, LRU or system is the CDCCL levied against? 

Overbraids installed on tail tank FQIS system wiring (FQIS wiring is located within wire 

assembly number AGS9124). 

3. What characteristic of the design configuration for this item must be retained under 

control of this Limitation, and why? 

The metal overbraid and/or DMS 2186 self adhering tape should be undamaged and 

exhibit no visible signs of deterioration. Damage and/or deterioration may reduce the 

shielding effectiveness of metallic overbraid. Undamaged DMS 2186 self adhering tape 

is an indicator that the underlying metallic overbraid is intact and undamaged. 

4. What is the specific Limitation? 

The metallic overbraiding and DMS 2186 self adhering tape (as applicable) shall be 

maintained per the original OEM type design or repair per SWPM 20-10-01 or AMM 20-

30-01. 

5. Were all applicable aircraft in compliance with this CDCCL at delivery from the 

OEM? If not, is there an applicable Service Bulletin or Service Rework package 

required for some aircraft? 

MD-11 Series All aircraft comply as originally delivered. 

6. When does this CDCCL become effective? 

This CDCCL becomes effective for all repairs performed after August 1, 2006. 

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MDC-02K1003 

Revision A 

BOEING PROPRIETARY INFORMATION 

Copyright © - The Boeing Company - Unpublished Work 

Page B22

CDCCL 20-13 - Trijet Wiring Near Fuel Tanks and Fuel Pipes 

1. What trijet model does this CDCCL apply to? 

DC-10 Series 

MD-10 Series 

MD-11 Series 

2. What part, LRU or system is the CDCCL levied against? 

All wiring used near the fuel tanks and fuel pipes. 

3. What characteristic of the design configuration for this item must be retained under 

control of this Limitation, and why? 

Proper wire assembly and wire installation techniques, wire bundle cleanliness, and 

adherence to the following requirements will minimize the likelihood that severe 

overheat or burn-through events will occur near fuel tanks and certain fuel pipes. 

4. What is the specific Limitation? 

Wires/wire assemblies, when installed within 6 inches of any fuel tank or fuel pipe, shall 

conform to Standard Wiring Practice Manual (Boeing Document Number D6-82481), 

Section 20-00-06. 

5. Were all applicable aircraft in compliance with this CDCCL at delivery from the 

OEM? If not, is there an applicable Service Bulletin or Service Rework package 

required for some aircraft? 

DC-10 Series All aircraft type designs comply. 

MD-10 Series All aircraft type designs comply. 

MD-11 Series All aircraft type designs comply. 

6. When does this CDCCL become effective? 

This CDCCL becomes effective for all repairs performed after August 1, 2006. 
MDC-02K1003 

Revision J 

BOEING PROPRIETARY INFORMATION 

Copyright © - The Boeing Company - Unpublished Work 

Page B23

CDCCL 20-14 – Trijet Float Switch Conduit Sleeves 

1. What trijet model does this CDCCL apply to? 

DC-10 Series with alternate conduit installed per SR10280079. 

MD-10 Series 

MD-11 Series 

2. What part, LRU or system is the CDCCL levied against? 

High Level Float Switch Conduit. 

Low Level Float Switch Conduit. 

3. What characteristic of the design configuration for this item must be retained under 

control of this Limitation, and why? 

Teflon® hoses are to be installed inside the float switch conduits to provide wire 

protection from chafing and shorting to the conduit wall. 

4. What is the specific Limitation? 

Any replacement conduit must have Teflon® hoses installed as built by the OEM or 

OEM Drawings or AMM or SWPM or any combination of those. 

Exception: MD-11 float switches installed in the Upper Auxiliary Tank are installed in 

bare metallic conduit (Conduit P/N AEP8600-505/-506/-513/-514). 

5. Were all applicable aircraft in compliance with this CDCCL at delivery from the 

OEM? If not, is there an applicable Service Bulletin or Service Rework package 

required for some aircraft? 

DC-10 Series All aircraft type designs complied with intent when delivered with 

integral liner conduit. 

DC-10 Series 10, 15, 30, 40 and KC-10A may install alternate 

conduit tubing with Teflon® liners installed per Service Rework 

Drawing SR10280079. 

MD-10 Series All aircraft type designs comply. 

MD-11 Series All aircraft type designs comply. 

6. When does this CDCCL become effective? 

This CDCCL becomes effective for all repairs performed after August 1, 2006. 

J 

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BOEING PROPRIETARY INFORMATION 

Copyright © - The Boeing Company - Unpublished Work 

Page B24

CDCCL 20-15 – Trijet Float and Pressure Switch Circuit Fuse Sleeves 

1. What model Trijet does this CDCCL apply to? 

 DC-10 Series 

 MD-10 Series 

 MD-11 Series 

2. What part, LRU or system is the CDCCL levied against? 

The fuse and DMS 2109 or DMS 2379 Type 4 sleeving material installed over the 

powered wire leads from the fuse to tank penetration point on float and pressure switch 

circuits. 

3. What characteristic of the design configuration for this item must be retained under 

control of this Limitation, and why? 

The fuse must be installed to protect the circuit. 

DMS 2109 or DMS 2379 Type 4 sleeving material must be installed between the fuse 

and the tank penetration point, to isolate the power lead from other wiring and provide 

additional wire protection from chafing and shorting. 

For fuse installations that incorporate a drip loop near the fuse, sleeving will only extend 

from tank penetration point to bottom of the drip loop. 

4. What is the specific Limitation? 

Any replacement fuse must be the same type as defined in the applicable service bulletin 

or Boeing approved part per SWPM 20-20-02. 

Any replacement or repair of wiring or sleeving from the fuse to tank penetration point 

must have DMS 2109 or DMS 2379 Type 4 sleeving installed per SWPM 20-10-01. 

5. Were all applicable aircraft in compliance with this CDCCL at delivery from the 

Original Equipment Manufacturer (OEM)? If not, is there an applicable Service Bulletin 

or Service Rework package required for some aircraft? 

DC-10 Series Service Bulletin DC10-28-252 revision New or later 

MD-10 Series Service Bulletin DC10-28-252 revision New or later 

MD-11 Series Service Bulletin MD11-28-132 revision New or later 

6. When does this CDCCL become effective? 

This CDCCL becomes effective after incorporation of Service Bulletin DC10-28-252 or 

MD11-28-132, as applicable.

F 

F 

F 
MDC-02K1003 

Revision A 

BOEING PROPRIETARY INFORMATION 

Copyright © - The Boeing Company - Unpublished Work 

Page B25

CDCCL 28-1 – Trijet Prohibit Safety Wire, Lockwire, Safety Cable or Cotter Pins Inside 

Fuel Tanks 

1. What trijet model does this CDCCL apply to? 

DC-10 Series 

MD-10 Series 

MD-11 Series 

2. What part, LRU or system is the CDCCL levied against? 

Inside airplane fuel tanks. 

3. What characteristic of the design configuration for this item must be retained under 

control of this Limitation, and why? 

The use of safety wire, lockwire, safety cable or cotter pins within fuel tanks are not 

permitted. 

Safety wire, lockwire, safety cable and cotter pins could become loose and have the 

potential to become FOD (foreign object debris) and cause filament heating, or arcing. 

4. What is the specific Limitation? 

Safety wire, lockwire, safety cable or cotter pins are not to be installed inside the fuel 

tanks. Components or equipment installed inside fuel tanks shall not use safety wire or 

cotter pins for hardware retention. Safety wire, lockwire, safety cable or cotter pins may 

be used if they are contained within the housing of an explosion proof, tank mounted 

LRU, and must be installed per applicable Original Equipment Manufacture (OEM) 

design/repair/maintenance documentation. In-shop LRU repairs must adhere to OEM 

Component Maintenance Manual (CMM) documented procedures and sole use of parts 

specified in the OEM’s CMM. 

5. Were all applicable aircraft in compliance with this CDCCL at delivery from the 

OEM? If not, is there an applicable Service Bulletin or Service Rework package 

required for some aircraft? 

DC-10 Series All airplane type designs comply. 

MD-10 Series All airplane type designs comply. 

MD-11 Series All airplane type designs comply. 

6. When does this CDCCL become effective? 

This CDCCL becomes effective for all repairs performed after August 1, 2006. 
MDC-02K1003 

Revision B 

BOEING PROPRIETARY INFORMATION 

Copyright © - The Boeing Company - Unpublished Work 

Page B26

CDCCL 28-2 - Trijet Fuel Pump (Boost or Transfer) and Housing Assemblies 

1. What model trijet does this CDCCL apply to? 

DC-10 Series 

MD-10 Series 

MD-11 Series 

2. What part, LRU or system is the CDCCL levied against? 

A. Fuel Booster Pump, Pumping Unit, Part Numbers 60-847-1A, 60-847-2, 60-847-3 and 

60-847-4. 

B. Fuel Booster Pump Housing Assembly, Part Numbers 60-843, 60-843M, 60-843-1, 60-

843-1M, 60-843-2, 60-843-2M, 60-845, 60-845M, 60-845-1, 60-845-1M, 60-845-2, and 

60-845-2M. 

C. Pump Inlet System Components 

3. What characteristic of the design configuration for this item must be retained under 

control of this Limitation, and why? 

Fuel pumps must be maintained to protect: 

 original Explosion-proof features, 

 electrical circuit integrity, 

 impeller and housing material, 

 protection from FOD ingestion, and 

 prevent exposure to mercury 

Faulty pump stators must be replaced in strict accordance with OEM documentation to 

protect the pump’s dry running and overheat performance as demonstrated in qualification 

tests. 

The pump must retain all features designed by the OEM to provide explosion proof 

properties. These include but are not limited to: Bearing materials and clearances, 

Housing materials and thickness, size of vent and cooling holes and installation of flamearresting plates, and metal-to-metal faying surfaces. 

The pump must retain all OEM features of the inlet housing shape, clearances, and 

materials as well as the materials of all other rotating components and stationary 

interfacing surfaces (reprime impellers, liners, plates, bearings, bearing assemblies, shafts, 

etc.). 
MDC-02K1003 

Revision F 

BOEING PROPRIETARY INFORMATION 

Copyright © - The Boeing Company - Unpublished Work 

Page B27

CDCCL 28-2 - Trijet Fuel Pump (Boost or Transfer) and Housing Assemblies 

(cont’d)

Pump inlet screens must be maintained as designed by Boeing and/or OEM. This is to 

prevent FOD ingestion. 

Electrical connectors must be repaired or replaced in strict accordance with OEM 

documentation to protect against electrical failures and maintain explosion proof 

characteristics. 

The pump stator lead wire routing inside the pump must be installed in strict accordance 

with OEM documentation so that it cannot contact the rotor and charge the rotor which 

could lead to an electrical arc outside of the pump’s explosion proof volume. 

Exposure of pump’s and housing’s aluminum components to mercury may result in 

material embrittlement, which could compromise critical design features of the pump or 

housing. 

 

4. What is the specific Limitation? 

Any repair to the fuel pumps must be made in accordance with the OEM’s Component 

Maintenance Manuals (CMMs) listed below or an FAA approved service bulletin. 

Part Number(s) CMM CMM Revision 

60-847-1A, 

60-847-2, 

60-847-3 

60-847-4 

28-22-03 8 

60-843-1, 

60-843-2, 

60-843-2M, 

60-843-3 

60-845-1, 

60-845-2, 

60-845-2M 

60-845-3 

28-22-01 5 

Any deviation from the OEM’s CMM must be justified by the modifier and approved by 

the FAA LA-ACO. 

Exposure of any pump or housing assembly, or their subcomponents to mercury is 

prohibited. 

F 
MDC-02K1003 

Revision A 

BOEING PROPRIETARY INFORMATION 

Copyright © - The Boeing Company - Unpublished Work 

Page B28

CDCCL 28-2 - Trijet Fuel Pump (Boost or Transfer) and Housing Assemblies 

(cont’d)

5. Were all applicable aircraft in compliance with this CDCCL at delivery from the 

OEM? If not, is there an applicable Service Bulletin or Service Rework package 

required for some aircraft? 

DC-10 Series All aircraft type designs comply. 

MD-10 Series All aircraft type designs comply. 

MD-11 Series All aircraft type designs comply. 

6. When does this CDCCL become effective? 

This CDCCL becomes effective for all repairs performed after August 1, 2006. 
MDC-02K1003 

Revision J 

BOEING PROPRIETARY INFORMATION 

Copyright © - The Boeing Company - Unpublished Work 

Page B29

CDCCL 28-3 – DC-10/MD-10 Fuel Pump (APU Start) and Housing Assemblies 

1. What model trijet does this CDCCL apply to? 

DC-10 Series 

MD-10 Series 

2. What part, LRU or system is the CDCCL levied against? 

A. Fuel Pump Assembly, Part Number 16710-1. 

B. Fuel Pump Housing Assembly, Part Numbers 16720-1, 16720-2. 

C. Pump Inlet System Components 

3. What characteristic of the design configuration for this item must be retained under 

control of this Limitation, and why? 

Fuel pumps must be maintained to protect: 

 original Explosion-proof features, 

 electrical circuit integrity, 

 impeller and housing material, 

 protection from FOD ingestion, and 

 prevent exposure to mercury. 

The pump must retain all features designed by the OEM to provide explosion proof 

properties. These include but are not limited to: Bearing materials and clearances, 

Housing materials and thickness, size of vent and cooling holes and installation of flamearresting plates, and metal-to-metal faying surfaces. 

Faulty pump stators must be replaced in strict accordance with OEM documentation to 

protect the pump’s dry running and overheat performance as demonstrated in qualification 

tests. 

Electrical connectors must be repaired or replaced in strict accordance with OEM 

documentation to protect against electrical failures and maintain explosion proof 

characteristics. 

The pump stator lead wire routing inside the pump must be installed in strict accordance 

with OEM documentation so that it cannot contact the rotor and charge the rotor which 

could lead to an electrical arc outside of the pump’s explosion proof volume. 
MDC-02K1003 

Revision J 

BOEING PROPRIETARY INFORMATION 

Copyright © - The Boeing Company - Unpublished Work 

Page B30

CDCCL 28-3 – DC-10/MD-10 Fuel Pump (APU Start) and Housing Assemblies 

(cont’d) 

The pump must retain all OEM features of the inlet housing shape, clearances, and 

materials as well as the materials of all other rotating components and stationary 

interfacing surfaces (reprime impellers, liners, plates, bearings, bearing assemblies, shafts, 

etc.). 

Pump inlet screens must be maintained as designed by Boeing and/or OEM. This is to 

prevent FOD ingestion. 

Exposure of pump’s and housing’s aluminum components to mercury may result in 

material embrittlement, which could compromise critical design features of the pump or 

housing. 

 

4. What is the specific Limitation? 

Any repair to the fuel pumps must be made in accordance with the OEM’s Component 

Maintenance Manuals (CMMs) or an FAA approved service bulletin. 

Part Number(s) CMM CMM Revision 

16710-1 28-23-01 1 

16720-1, 

16720-2 

28-23-02 10 

Any deviation from the OEM’s CMM must be justified by the modifier and approved by 

the FAA LA-ACO. 

Exposure of any pump or housing assembly, or their subcomponents to mercury is 

prohibited. 

5. Were all applicable aircraft in compliance with this CDCCL at delivery from the 

OEM? If not, is there an applicable Service Bulletin or Service Rework package 

required for some aircraft? 

DC-10 Series All aircraft type designs comply. 

MD-10 Series All aircraft type designs comply. 

6. When does this CDCCL become effective? 

This CDCCL becomes effective for all repairs performed after August 1, 2006. 

J 
MDC-02K1003 

Revision E 

BOEING PROPRIETARY INFORMATION 

Copyright © - The Boeing Company - Unpublished Work 

Page B31

CDCCL 28-4 – KC-10 and KDC-10 Fuel Pump Assembly 

1. What model trijet does this CDCCL apply to? 

All KC-10 and KDC-10 airplanes. 

2. What part, LRU or system is the CDCCL levied against? 

A. Fuel Pump Assembly, Part Number RR12690. 

3. What characteristic of the design configuration for this item must be retained under 

control of this Limitation, and why? 

CDCCL has been moved to Report MDC-09K1000 “KC-10A AND KDC-10 SPECIAL 

COMPLIANCE ITEM REPORT SUPPLEMENT” 

If the CDCCL is applicable, contact Boeing Export Control to obtain a copy of the 

supplemental report.
MDC-02K1003 

Revision E 

BOEING PROPRIETARY INFORMATION 

Copyright © - The Boeing Company - Unpublished Work 

Page B32

CDCCL 28-4 – KC-10 and KDC-10 Fuel Pump Assembly 

(cont’d) 

CDCCL has been moved to Report MDC-09K1000 “KC-10A AND KDC-10 SPECIAL 

COMPLIANCE ITEM REPORT SUPPLEMENT” 
MDC-02K1003 

Revision A 

BOEING PROPRIETARY INFORMATION 

Copyright © - The Boeing Company - Unpublished Work 

Page B33

CDCCL 28-5 – MD-11 Fuel Pump and Canister Assemblies 

1. What model trijet does this CDCCL apply to? 

MD-11 Series airplanes with optional 2,000 gallon forward auxiliary tanks(s) installed. 

2. What part, LRU or system is the CDCCL levied against? 

A. Fuel Pump, Type 8410, Part Number 568-1-27202, Mark -002. 

B. Fuel Pump Canister, Type 9114, Part Number 568-1-29104, Mark –001. 

C. Pump Inlet System Components 

3. What characteristic of the design configuration for this item must be retained under 

control of this Limitation, and why? 

Fuel pumps must be maintained to protect: 

 original Explosion-proof features, 

 electrical circuit integrity, 

 impeller and housing material, 

 protection from FOD ingestion, and 

 prevent exposure to mercury. 

Faulty pump stator assemblies must be replaced or repaired in strict accordance with OEM 

documentation to protect the pump’s dry running and overheat performance as 

demonstrated in qualification tests. 

The pump must retain all features designed by the OEM to provide explosion proof 

properties. These include but are not limited to: Bearing materials and clearances, canister 

materials and thickness, size of vent and cooling holes and installation of flame-arresting 

plates, and metal-to-metal faying surfaces. 

The pump must retain all OEM features of the inlet housing shape, clearances, and 

materials as well as the materials of all other rotating components and stationary 

interfacing surfaces (reprime impellers, liners, plates, bearings, bearing assemblies, shafts, 

etc.). 

Pump inlet screens must be maintained as designed by Boeing and/or OEM. This is to 

prevent FOD ingestion. 
MDC-02K1003 

Revision B 

BOEING PROPRIETARY INFORMATION 

Copyright © - The Boeing Company - Unpublished Work 

Page B34

CDCCL 28-5 – MD-11 Fuel Pump and Canister Assemblies 

(Cont’d) 

Electrical connectors must be repaired or replaced in strict accordance with OEM 

documentation to protect against electrical failures and maintain explosion proof 

characteristics. 

The pump stator lead wire routing inside the pump must be installed in strict accordance 

with OEM documentation so that it cannot contact the rotor and charge the rotor which 

could lead to an electrical arc outside of the pump’s explosion proof volume. 

Exposure of pump’s and housing’s aluminum components to mercury may result in 

material embrittlement, which could compromise critical design features of the pump or 

housing. 

 

4. What is the specific Limitation? 

Any repair to the fuel pumps must be made in accordance with the OEM’s Component 

Maintenance Manuals (CMMs) listed below or an FAA approved service bulletin. 

Part Number(s) CMM CMM Revision 

568-1-27202-002 28-21-51 11 

568-1-29104-001 28-21-52 8 

Any deviation from the OEM’s CMM must be justified by the modifier and approved by 

the FAA LA-ACO. 

Exposure of any pump or housing assembly, or their subcomponents to mercury is 

prohibited. 

5. Were all applicable aircraft in compliance with this CDCCL at delivery from the 

OEM? If not, is there an applicable Service Bulletin or Service Rework package 

required for some aircraft? 

MD-11 Series All aircraft type designs comply. 

6. When does this CDCCL become effective? 

This CDCCL becomes effective for all repairs performed after August 1, 2006. 
MDC-02K1003 

Revision A 

BOEING PROPRIETARY INFORMATION 

Copyright © - The Boeing Company - Unpublished Work 

Page B35

CDCCL 28-6 – Trijet Fuel Pump (APU Start) Assembly 

1. What model trijet does this CDCCL apply to? 

DC-10 Series - aircraft that have incorporated McDonnell Douglas/Douglas Aircraft 

Company DC-10 Service Bulletin 28-187 revision 1 dated 5/7/1990 or later. 

MD-10 Series - aircraft that have incorporated McDonnell Douglas/Douglas Aircraft 

Company DC-10 Service Bulletin 28-187 revision 1 dated 5/7/1990 or later. 

MD-11 Series 

2. What part, LRU or system is the CDCCL levied against? 

Fuel Pump Assembly, Part Number 218387. 

3. What characteristic of the design configuration for this item must be retained under 

control of this Limitation, and why? 

Fuel pumps must be maintained to protect: 

 original Explosion-proof features, 

 electrical circuit integrity, 

 impeller and housing material, 

 protection from FOD ingestion, and 

 prevent exposure to mercury. 

The pump must retain all features designed by the OEM to provide explosion proof 

properties. These include but are not limited to: Bearing materials and clearances, pump 

housing materials and thickness, size of vent and cooling holes, and metal-to-metal faying 

surfaces. 

Faulty pump stators must be replaced in strict accordance with OEM documentation to 

protect the pump’s dry running and overheat performance as demonstrated in qualification 

tests. In addition, Thermal Fuses must be replaced in strict accordance with OEM 

documentation each time motor stator winding is removed for repair to ensure repeated 

reinstallation of the same thermal fuse does not compromise the pump’s overheat 

protection. 

Electrical connectors must be repaired or replaced in strict accordance with OEM 

documentation to protect against electrical failures and maintain explosion proof 

characteristics. 

The pump stator lead wire routing inside the pump must be installed in strict accordance 

with OEM documentation so that it cannot contact the rotor and charge the rotor which 

could lead to an electrical arc outside of the pump’s explosion proof volume. 
MDC-02K1003 

Revision E 

BOEING PROPRIETARY INFORMATION 

Copyright © - The Boeing Company - Unpublished Work 

Page B36

CDCCL 28-6 – Trijet Fuel Pump (APU Start) Assembly 

(cont’d) 

The pump must retain all OEM features of the inlet housing shape, clearances, and 

materials as well as the materials of all other rotating components and stationary 

interfacing surfaces (impellers, liners, plates, bearings, bearing assemblies, shafts, etc.). 

Pump inlet screens must be maintained as designed by Boeing and/or OEM. This is to 

prevent FOD ingestion. 

Exposure of pump assembly’s aluminum components to mercury may result in material 

embrittlement, which could compromise critical design features of the pump. 

 

4. What is the specific Limitation? 

Any repair to the fuel pumps must be made in accordance with the OEM’s Component 

Maintenance Manuals (CMMs) or an FAA approved service bulletin. 

Part Number(s) CMM CMM Revision 

218387 28-20-02 12 

Any deviation from the OEM’s CMM must be justified by the modifier and approved by 

the FAA LA-ACO. 

Exposure of any pump or housing assembly, or their subcomponents to mercury is 

prohibited. 

5. Were all applicable aircraft in compliance with this CDCCL at delivery from the 

OEM? If not, is there an applicable Service Bulletin or Service Rework package 

required for some aircraft? 

DC-10 Series All aircraft comply with incorporation of McDonnell Douglas/ 

Douglas Aircraft Company Service Bulletin DC10-28-187 revision 1 

dated 5/7/1990 or later and a fuel pump assembly that meets the 

requirements of this CDCCL. 

MD-10 Series All aircraft comply with incorporation of McDonnell Douglas/ 

Douglas Aircraft Company Service Bulletin DC10-28-187 revision 1 

dated 5/7/1990 or later and a fuel pump assembly that meets the 

requirements of this CDCCL. 

MD-11 Series All aircraft comply as originally delivered. 

6. When does this CDCCL become effective? 

This CDCCL becomes effective for all repairs performed after August 1, 2006. 

E 
MDC-02K1003 

Revision E 

BOEING PROPRIETARY INFORMATION 

Copyright © - The Boeing Company - Unpublished Work 

Page B37

CDCCL 28-7 – DC-10 Fuel Quantity Master Indicators 

1. What trijet model does this CDCCL apply to? 

DC-10 Series 

2. What part, LRU or system is the CDCCL levied against? 

All DC-10 airplanes which utilize the following fuel quantity gauging system (FQGS) 

components: 

 Master indicator P/N’s 217-003-xxx (where xxx is 001 thru 003, 005 thru 007, 011, 

012, 016, 103/M, 105/M thru 107/M, 109/M, 111/M, 112/M, 114/M, 116/M thru 

118/M, 126/M, and 130/M) for Parker/Gull FQGS installations 

3. What characteristic of the design configuration for this item must be retained under 

control of this Limitation, and why? 

FQGS master indicator maintenance procedures must be controlled to protect its internal 

electrical circuit integrity, limiting operational and failure conditions to a known set of 

results. 

4. What is the specific Limitation? 

Any repair to a FQGS master indicator must be made in accordance with the OEM’s 

Component Maintenance Manuals (CMMs) listed below or an FAA approved service 

bulletin. 

Part Number(s) CMM CMM Revision 

217-003-001, 

217-003-002 

28-41-20 8 E 
MDC-02K1003 

Revision E 

BOEING PROPRIETARY INFORMATION 

Copyright © - The Boeing Company - Unpublished Work 

Page B38

CDCCL 28-7 – DC-10 Fuel Quantity Master Indicators 

(cont’d) 

Part Number(s) CMM CMM Revision 

217-003-003, 

217-003-009, 

217-003-103, 

217-003-103M, 

217-003-109, 

217-003-109M, 

217-003-011, 

217-003-012, 

217-003-016, 

217-003-111, 

217-003-111M, 

217-003-112, 

217-003-112M, 

217-003-116, 

217-003-116M 

28-41-20 8 

217-003-005, 

217-003-006, 

217-003-007, 

217-003-105, 

217-003-105M, 

217-003-106, 

217-003-106M, 

217-003-107, 

217-003-107M, 

217-003-114, 

217-003-114M, 

217-003-118, 

217-003-118M 

28-41-17 6 

217-003-117, 

217-003-117M, 

217-003-130, 

217-003-130M 

28-41-24 2 

217-003-126, 

217-003-126M 

217-003-132, 

217-003-132M 

28-41-25 2 

Any deviation from the OEM’s CMM must be justified by the modifier and approved by 

the FAA LA-ACO. 

E 
MDC-02K1003 

Revision A 

BOEING PROPRIETARY INFORMATION 

Copyright © - The Boeing Company - Unpublished Work 

Page B39

CDCCL 28-7 – DC-10 Fuel Quantity Master Indicators 

(cont’d) 

5. Were all applicable aircraft in compliance with this CDCCL at delivery from the 

OEM? If not, is there an applicable Service Bulletin or Service Rework package 

required for some aircraft? 

DC-10 Series All airplane type designs comply. 

6. When does this CDCCL become effective? 

This CDCCL becomes effective for all repairs performed after August 1, 2006. 
MDC-02K1003 

Revision J 

BOEING PROPRIETARY INFORMATION 

Copyright © - The Boeing Company - Unpublished Work 

Page B40

CDCCL 28-8 – MD-11 Fuel Quantity Standard Electronic Module, Densitometer, MultiJunction Probe, and Ultrasonic Processor Drive Unit 

1. What trijet model does this CDCCL apply to? 

MD-11 Series 

2. What part, LRU or system is the CDCCL levied against? 

Fuel quantity gauging system (FQGS) Standard Electronic Module (SEM), Densitometer, 

Multi-Junction Probe (MJP), and Ultrasonic Processor Drive Unit (PDU). 

 SEM P/N’s 367-040-074, 367-040-080, 367-040-081, 367-040-084 and 367-040-085 

for Parker/Gull FQGS installations 

 Densitometer P/N’s 180-022-001 for Parker/Gull FQGS installations 

 MJP P/N’s 003-008-001 thru 003-008-006 and 003-008-008 for Parker/Gull FQGS 

installations 

 Ultrasonic PDU P/N 366-026-001 for Parker/Gull FQGS installations 

3. What characteristic of the design configuration for this item must be retained under 

control of this Limitation, and why? 

FQGS SEM, densitometer, MJP, and ultrasonic PDU maintenance procedures must be 

controlled to protect its internal electrical circuit integrity, limiting operational and failure 

conditions to a known set of results. 

4. What is the specific Limitation? 

Any repair to a FQGS SEM, densitometer, MJP, and ultrasonic PDU must be made in 

accordance with the OEM’s Component Maintenance Manuals (CMMs) listed below or an 

FAA approved service bulletin. 

Part Number(s) CMM CMM Revision 

(SEM) 

367-040-073 

367-040-074 

367-040-080 

367-040-081 

367-040-083 

367-040-084 

367-040-085 

367-040-086 

28-40-88 11 

(Densitometer) 

180-022-001 

28-40-87 5 J 
MDC-02K1003 

Revision J 

BOEING PROPRIETARY INFORMATION 

Copyright © - The Boeing Company - Unpublished Work 

Page B41

CDCCL 28-8 – MD-11 Fuel Quantity Standard Electronic Module, Densitometer, MultiJunction Probe, and Ultrasonic Processor Drive Unit 

(cont’d) 

Part Number(s) CMM CMM Revision 

(MJP) 

003-008-001 thru 003-008-

006, 

003-008-008, 

003-008-208 thru 003-008-

213 

28-40-86 6 

(Ultrasonic PDU) 

366-026-001 

28-41-63 1 

Any deviation from the OEM’s CMM must be justified by the modifier and approved by 

the FAA LA-ACO. 

5. Were all applicable aircraft in compliance with this CDCCL at delivery from the 

OEM? If not, is there an applicable Service Bulletin or Service Rework package 

required for some aircraft? 

MD-11 Series All airplane type designs comply. 

6. When does this CDCCL become effective? 

This CDCCL becomes effective for all repairs performed after August 1, 2006. 
MDC-02K1003 

Revision A 

BOEING PROPRIETARY INFORMATION 

Copyright © - The Boeing Company - Unpublished Work 

Page B42

CDCCL 28-9 – MD-10 Fuel Quantity Processor Unit 

1. What trijet model does this CDCCL apply to? 

MD-10 Series 

2. What part, LRU or system is the CDCCL levied against? 

Fuel quantity gauging system (FQGS) Fuel Quantity Processor Unit. 

 FQPU P/N 30163-01 for Goodrich FQGS installations 

3. What characteristic of the design configuration for this item must be retained under 

control of this Limitation, and why? 

FQGS FQPU maintenance procedures must be controlled to protect its internal electrical 

circuit integrity, limiting operational and failure conditions to a known set of results. 

4. What is the specific Limitation? 

Any repair to a FQGS FQPU must be made in accordance with the OEM’s engineering 

drawings and tested per the OEM’s production ATP, or an FAA approved service bulletin. 

Any deviation from the OEM data must be justified by the modifier and approved by the 

FAA LA-ACO. 

5. Were all applicable aircraft in compliance with this CDCCL at delivery from the 

OEM? If not, is there an applicable Service Bulletin or Service Rework package 

required for some aircraft? 

MD-10 Series All airplane type designs comply. 

6. When does this CDCCL become effective? 

This CDCCL becomes effective for all repairs performed after August 1, 2006. 
MDC-02K1003 

Revision A 

BOEING PROPRIETARY INFORMATION 

Copyright © - The Boeing Company - Unpublished Work 

Page C1

Appendix C 

Airworthiness Limitation Instruction (ALIs) 

 
MDC-02K1003 

Revision A 

BOEING PROPRIETARY INFORMATION 

Copyright © - The Boeing Company - Unpublished Work 

Page C2

TRIJET AIRWORTHINESS LIMIATION INSTRUCTIONS 

For some trijet system functions, compliance with SFAR 88 and Advisory Circular (AC) 25.981-

1C require inspections for certain design configurations, using AC 25-19 “Certification 

Maintenance Requirements (CMRs)” methodology as a guide. 

Similarly, Airworthiness Limitation Instruction (ALIs) are a means of detecting safety significant 

conditions, potentially making the airplane non-compliant with SFAR 88 and FAR 25.981(b). 

When an ALI detects such a condition, maintenance action to correct it is required. 

The terms of the trijet Type Certificate are only valid when associated checks specified by these 

ALIs are performed within the time intervals specified. ALIs are equivalent to one-star CMRs 

(per AC 25-19): The configuration control checks and intervals specified are mandatory and 

cannot be changed, escalated, or deleted without the approval of FAA Engineering of the Los 

Angeles Aircraft Certification Office (LA-ACO). 

Temporary deviations from the ALI intervals are permitted within the limitations of Appendix D. 

While each ALI is included in this report, it is required that each ALI also be included in an 

appropriate document where it will be visible to airline personnel; therefore each ALI must be 

included in each Operator's Maintenance Program. SFAR88 established requirements for ALIs; 

it includes an implementation schedule of changes to the operator’s maintenance program to 

manage compliance with these limitations and implementation of these checks. 

All maintenance and repair instructions provided by Boeing have been updated where required to 

ensure compatibility with these inspections. 
MDC-02K1003 

Revision A 

BOEING PROPRIETARY INFORMATION 

Copyright © - The Boeing Company - Unpublished Work 

Page C3

Each ALI specified herein includes the name of the system in which the ALI is needed, and the 

following information: 

1. What model trijet does this ALI apply to? 

2. What part, LRU or system is the ALI levied against? 

3. What part, LRU or system characteristic is being looked for? 

4. How is it found? 

5. What checks are to be performed? 

6. Is test equipment needed? 

7. What is the pass-fail criteria? 

8. What is the ALI accomplishment interval? 

9. When does this ALI become effective? 

Please report any negative inspection results to your local Boeing Field Service Representative. 

If the Boeing Field Service Representative is not available, you may send the report to: 

The Boeing Company 

3855 Lakewood Blvd. 

Long Beach, CA, USA 90846 

Attn: 

Manager - Avionics & Electrical Systems (Dept. L33) 

Service Engineering 

Technical Services & Modifications 

Mail Code: D800-0035 
MDC-02K1003 

Revision A 

BOEING PROPRIETARY INFORMATION 

Copyright © - The Boeing Company - Unpublished Work 

Page C4

ALI 20-1 - Trijet Fuel Pump and Auxiliary Hydraulic Pump Circuit Breaker Reset 

1. What trijet model does this ALI apply to? 

DC-10 Series 

MD-10 Series 

MD-11 Series 

2. What part, LRU or system is the ALI levied against? 

All fuel pump and auxiliary hydraulic pump circuit breakers 

3. What part, LRU or system characteristic is being looked for? 

This limitation prohibits the resetting of any tripped fuel pump and auxiliary hydraulic 

pump circuit breakers until it has been determined it is safe to do so. 

4. How is it found? 

Tripped fuel pump and auxiliary hydraulic pump circuit breakers will be reported by 

flight crew and will generate maintenance action. 

5. What checks are to be performed? 

Verify it is safe to reset the circuit breaker(s) by following the applicable OEM 

troubleshooting procedures. Fault(s) that resulted in circuit breaker trip must be isolated 

and corrected prior to reset if the fault(s) occurred inside the fuel tank or adjacent to any 

fuel tank wall. 

6. Is test equipment needed? 

Yes, standard electrical tools. 

7. What is the pass-fail criteria? 

Pass - It is safe to reset the circuit breaker(s) if the troubleshooting procedures are 

successfully completed, and problem has been corrected. 

Fail - It is not safe to reset the circuit breaker(s) if the troubleshooting procedures are not

successfully completed. 

8. What is the ALI accomplishment interval? 

There is no fixed inspection interval. This ALI applies only when the open circuit 

breaker condition occurs in service. 
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ALI 20-1 - Trijet Fuel Pump and Auxiliary Hydraulic Pump Circuit Breaker Reset 

(cont’d) 

9. When does this ALI become effective? 

August 2, 2006 
MDC-02K1003 

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Page C6

ALI 20-2 - MD-11 Inspection of Tail Tank FQGS Wiring Overbraid 

1. What trijet model does this ALI apply to? 

MD-11 Series 

2. What part, LRU or system is the ALI levied against? 

Metallic overbraiding installed on tail tank FQIS wiring (FQIS wiring is located within 

wire assembly number AGS9124). 

3. What part, LRU or system characteristic is being looked for? 

The metal overbraid and/or DMS 2186 self adhering tape should be continuous (in 

wrapped area), undamaged, and exhibit no signs of deterioration. 

4. How is it found? 

Detailed inspection. 

5. What checks are to be performed? 

(a) Verify that DMS 2186 self adhering tape is undamaged and does not exhibit 

deterioration. See Figure (a). 

(b) Verify that metallic overbraid (in areas not covered by DMS 2186 self adhering tape) 

is undamaged and does not exhibit deterioration. See Figure (b). 

Figure (a) 

DMS 

2186 

Tape

DMS 

2186 

Tape 
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ALI 20-2 - MD-11 Inspection of Tail Tank FQGS Wiring Overbraid 

(cont’d) 

Figure (b)

6. Is test equipment needed? 

No. 

7. What is the pass-fail criteria? 

Pass - DMS 2186 self adhering tape and metallic overbraid (in areas not covered by “red 

wrap” tape) do not exhibit damage or deterioration. 

Fail - DMS 2186 self adhering tape and metallic overbraid (in areas not covered by “red 

wrap” tape) exhibits damage or deterioration. Repair per SWPM 20-10-01 

8. What is the ALI accomplishment interval? 

5 years 

9. When does this ALI become effective? 

August 2, 2006 

Metallic 

Overbraid 

H 
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Page D1

APPENDIX D - SHORT-TERM EXTENSIONS 

Since SCIs and ALIs are based on analysis using AC 25-19 methodology, temporary deviation 

from the SCI/ALI intervals in this document are permitted in accordance with the limitations 

within this Appendix. Such an extension should be handled similar to the operator's Approved 

Short-term Escalation Procedures. Each time an operator uses such a temporary SCI/ALI 

interval extension, the operator must notify their local regulatory authority (e.g. Principle 

Maintenance Inspector) as soon as practicable that a short-term extension has been utilized. 

Any deviation beyond the limitations within this Appendix requires approval of the responsible 

Los Angeles Aircraft Certification Office (LA-ACO), prior to its use. Extensions within the 

limitations of this Appendix have LA-ACO approval. 

 o Deviations are permitted only for an exceptional, short-term extension of an individual 

SCI/ALI for a specific airplane. 

 o Repeated use of extensions, either on the same airplane or on similar airplanes in the 

operator's fleet, must not be used as a substitute for good management practices. 

 o Repeated extensions for the same SCI/ALI are not allowed. 

 o Extensions may not be used for fleet SCI/ALI escalation or extension. 

 o Short-term is defined as 10% of the SCI/ALI interval, up to a maximum of 30 days; this 

is applicable to each SCI/ALI in this report unless specifically defined in the applicable 

SCI/ALI. 

 o The purpose of this Appendix is to allow very short-term "get home" capability in those 

exceptional cases where uncontrollable or unexpected events ground an airplane with 

insufficient time remaining on a SCI/ALI. It is intended that use of such short-term 

exceptional extensions be rare. If they are desired more often at an airline, it is evidence 

of trouble in maintenance planning. It is not allowed to repetitively use the authority of 

this Appendix for relief for such a situation.