# Boeing Alert Service Bulletin 757-27A0144: Revision 1

- Rights: © The Boeing Company. Filed by the FAA in regulations.gov docket FAA-2011-1093; AD 2012-16-16 incorporates this document by reference. Not covered by OpenAirDocs’ CC0 dedication.
- Document: [Boeing Alert Service Bulletin 757-27A0144](https://openairdocs.org/service-documents/boeing/757-27a0144.md)
- Title as filed: U.S. DOT/FAA - Service Bulletin
- Pages: 29
- PDF: https://openairdocs.org/files/sha256/03/f1/03f14b97b84079c045cee47f7e370f3879ef685cb0c53e147e6be98cc00390bf
- Page: https://openairdocs.org/service-documents/boeing/757-27a0144/file/03f14b97b840

## Text

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### Page 1

Commercial 
Airplanes
757
Service Bulletin
ALERT
Number: 757-27A0144
Original Issue: August 07, 2003
Revision 1: January 20, 2010
ATA System: 2741
SUBJECT: FLIGHT CONTROLS - Horizontal Stabilizer - Horizontal Stabilizer Trim Actuator -
Ballscrew Freeplay Check Addition and Lubrication Interval Change
Export of this technology is controlled under the United States Export Administration Regulations (EAR) (15
CFR 730-774). An export license may be required before it is used for development, production or use by foreign
persons from specific countries. The controller of this data has the individual responsibility to abide by all export
laws.
9E991ECCN:
BOEING PROPRIETARY, CONFIDENTIAL, AND/OR TRADE SECRET
Copyright © 2003 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Unpublished Work - All Rights Reserved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.
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2.0

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ALERTALERT
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Table of Contents
Revision Transmittal Sheet ............................................ 5
Summary ...................................................... 7
1. PLANNING INFORMATION ........................................ 1 1
A. Effectivity ............................................... 1 1
1. Airplanes ............................................ 1 1
2. Spares Affected ........................................ 1 5
B. Concurrent Requirements ...................................... 1 5
C. Reason ................................................ 1 5
D. Description .............................................. 1 6
E. Compliance .............................................. 1 7
F. Approval ............................................... 2 0
G. Manpower .............................................. 2 0
H. Weight and Balance Changes .................................... 2 0
I. Electrical Load Data ......................................... 2 0
J. References .............................................. 2 1
1. Existing Data: ......................................... 2 1
2. Data supplied with this Service Bulletin: ........................... 2 1
3. Installation Drawings Used in the Preparation of this Service Bulletin: ........... 2 1
K. Publications Affected ........................................ 2 1
L. Interchangeability and Intermixability of Parts ........................... 2 1
2. MATERIAL INFORMATION ........................................ 2 3
A. Material - Price and Availability ................................... 2 3
B. Industry Support Information .................................... 2 3
C. Parts Necessary For Each Airplane ................................. 2 3
1. Kits/Parts: ........................................... 2 3
2. Parts and Materials Supplied by the Operator: ........................ 2 3
3. Parts Modified and Reidentified: ............................... 2 3
4. Parts Removed and Not Replaced: .............................. 2 3
D. Parts Necessary to Change Spares ................................. 2 3
E. Special Tooling - Price and Availability ............................... 2 3
F. Special Tooling Necessary to do this Service Bulletin ....................... 2 3
3. ACCOMPLISHMENT INSTRUCTIONS .................................. 2 5
A. GENERAL INFORMATION ..................................... 2 5
B. WORK INSTRUCTIONS ....................................... 2 5
FIGURE 1: INSPECTION OF HORIZONTAL STABILIZER BALLSCREW LOAD PATH ........ 2 7
FIGURE 2: HORIZONTAL STABILIZER BALLSCREW AND BALLNUT FREEPLAY CHECK ..... 2 8
FIGURE 3: HORIZONTAL STABILIZER TRIM BALLSCREW ACTUATOR REPLACEMENT ..... 2 9
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757-27A0144Revision 1: January 20, 2010
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BOEING SERVICE BULLETIN 757-27A0144
ALERTALERT
BLANK PAGE

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Commercial 
Airplanes
757
Service Bulletin
ALERT
Revision Transmittal SheetNumber: 757-27A0144Original Issue: August 07, 2003
Revision 1: January 20, 2010
ATA System: 2741
SUBJECT: FLIGHT CONTROLS - Horizontal Stabilizer - Horizontal Stabilizer Trim Actuator -
Ballscrew Freeplay Check Addition and Lubrication Interval Change
This Revision includes all pages of the service bulletin.
COMPLIANCE INFORMATION RELATED TO THIS REVISION
No more work is necessary on airplanes changed as shown in the original issue of this service bulletin. However,
operators must continue to do the repeat detailed inspection, lubrication and freeplay check in accordance with
Paragraph 1.E., Compliance.
REASON FOR REVISION
This revision is sent to change the compliance times of the detailed inspection, lubrication and ballnut-to-ballscrew
freeplay check. Instructions on how to accomplish the detailed inspection are replaced by an instruction to do
the detailed inspection in accordance with the Aircraft Maintenance Manual (AMM) and Part 3 is added to the
work instructions to give lubrication instructions. This revision also adds an Airworthiness Directive (AD) statement
and removes all figures as the procedures are now accomplished by the AMM.
These sections are changed:
1. Summary:
– Background: A interim notification of a revision to the Maintenance Planning Document (MPD) statement
is removed.
– Action: The statement is updated to agree with the updated work instructions.
– Compliance: An Airworthiness Directive (AD) statement is added.
– Manpower: The manpower table is removed.
– Illustration: The summary illustration paragraph is updated.
2. Planning Information:
– Paragraph 1.A., Effectivity: A group configuration table is added which splits the effectivity into 3
configurations.
– Paragraph 1.C., Reason: A interim notification of a revision to the Maintenance Planning Document
(MPD) statement is removed.
– Paragraph 1.D., Description: The statement is updated to agree with the updated work instructions and
maintenance zones are added.
– Paragraph 1.E., Compliance: An Airworthiness Directive (AD) statement is added.
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– Paragraph 1.E., Compliance: The compliance times and repeat intervals for the detailed inspection,
lubrication and freeplay check in Tables 1 and 2 are changed. The corrective action for damaged parts
is added, footnotes (a) and (b) are changed and footnote (c) is deleted.
– Paragraph 1.E., Compliance: The compliance times and repeat intervals for the detailed inspection,
lubrication and freeplay check in Table 3 are changed. The corrective action for damaged parts is
added, footnotes (a) and (b) are changed and footnotes (c) and (d) are deleted.
– Paragraph 1.G., Manpower: The manpower table is updated.
3. Accomplishment Instructions:
– Paragraph 3.B., Work Instructions: A note is deleted from Part 1, Step 1 and the access, cleaning,
lubrication and detailed inspection instructions are replaced by one instruction to do a detailed inspection
in accordance with the AMM.
– Paragraph 3.B., Work Instructions: The access instruction is removed from Part 2 and an AMM task
is added to the instruction to do the stabilizer ballscrew to ballnut freeplay check.
– Paragraph 3.B., Work Instructions: Part 3 is added to give lubrication instructions.
– Figure 1: This Figure is deleted.
– Figure 2: This Figure is deleted.
– Figure 3: This Figure is deleted.
Vertical lines are put on the left edge of each page, except in Paragraph 1.A., Effectivity, to show the location
of important changes.
Pages with no vertical lines have no important changes.
REVISION HISTORY
August 07, 2003Original Issue:
January 20, 2010Revision 1:
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BOEING SERVICE BULLETIN 757-27A0144
ALERTALERT

### Page 7

Commercial 
Airplanes
757
Service Bulletin
ALERT
SummaryNumber: 757-27A0144Original Issue: August 07, 2003
Revision 1: January 20, 2010
ATA System: 2741
SUBJECT: FLIGHT CONTROLS - Horizontal Stabilizer - Horizontal Stabilizer Trim Actuator -
Ballscrew Freeplay Check Addition and Lubrication Interval Change
THIS BULLETIN IS SENT TO THE OPERATORS OF RECORD OF THE AIRPLANES SHOWN IN PARAGRAPH
1.A., EFFECTIVITY. IF AN AIRPLANE HAS BEEN LEASED OR SOLD, SEND THIS SERVICE BULLETIN TO
THE NEW OPERATOR. IF APPLICABLE SPARES HAVE BEEN SOLD, SEND THIS SERVICE BULLETIN TO
THE NEW OWNER.
CONCURRENT REQUIREMENTS
None.
BACKGROUND
This service bulletin is being issued to provide a new stabilizer ballscrew lubrication interval and detailed inspection
interval. Also, a new stabilizer ballscrew to ballnut freeplay check is included with a recommended check interval.
The inspections/check are an added level of protection which reduces the potential of unlikely failure modes of
the stabilizer ballscrew assembly used on the stabilizer actuator. The inspections/check can be run in-situ on
the airplane
After an MD-80 horizontal stabilizer jackscrew incident, a design review was initiated of the Boeing heritage
horizontal stabilizer ballscrews. During this review, an operator reported a 757 horizontal stabilizer ballscrew
with extensive corrosion. An investigation was initiated. This investigation identified that a maintenance procedure
to check the stabilizer ballscrew primary load path was required. Loss of the horizontal stabilizer ballscrew
primary and secondary load paths, although extremely improbable, could potentially result in the loss of control
of the airplane.
Boeing Service Related Problem (SRP) 757-SRP-27-0153 is related to this service bulletin.
NOTE: Service Bulletin 757-27-0137 served as an interim maintenance action related to 757-SRP-27-0153.
Service Bulletin 757-27A0144 is the final maintenance recommendation related to 757-SRP-27-0153.
Upon release of Service Bulletin 757-27A0144, operators should perform the maintenance actions in
that bulletin rather than those in Service Bulletin 757-27-0137. However, it should be noted that Service
Bulletin 757-27-0137 includes one maintenance action that is not included in Service Bulletin
757-27A0144: lubrication of the stabilizer pivot hinges. Lubrication of the stabilizer pivot hinges was
included in Service Bulletin 757-27-0137 as a convenience; it is unrelated to the safety issue addressed
in safety 757-SRP-27-0153. Boeing recommends that operators continue to perform the stabilizer hinge
lubrication task per 757 MPD Volume 1 Section 5, and 757 AMM 12-21-05.
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ACTION
Get access to the horizontal stabilizer trim ballscrew actuator and do the procedures that follow below at the
intervals shown in Paragraph 1.E., Compliance:
– Do a detailed inspection of the stabilizer ballscrew assembly.
– Lubricate the horizontal stabilizer trim control system.
– Do a stabilizer ballscrew to ballnut freeplay check.
– Replace damaged and/or cracked and/or worn stabilizer trim ballscrew actuators.
EFFECTIVITY
All 757-200/-200CB/-200PF Airplanes. Refer to Paragraph 1.A.1., Airplanes for the list of affected airplanes.
COMPLIANCE
The Federal Aviation Administration (FAA) will possibly release an Airworthiness Directive related to this service
bulletin. The Airworthiness Directive will make the compliance tasks and times given in this service bulletin
mandatory.
Refer to Paragraph 1.E., Compliance.
INDUSTRY SUPPORT INFORMATION
Boeing warranty remedies are not available for the tasks given in this service bulletin.
MANPOWER
Refer to Paragraph 1.G., Manpower.
MATERIAL INFORMATION
Operator Supplied Parts/Materials.
Refer to Paragraph 2.A., Material - Price and Availability.
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BOEING SERVICE BULLETIN 757-27A0144
ALERT  ALERT
STA
1768
DO A DETAILED INSPECTION OF THE
STABILIZER BALLSCREW ASSEMBLY.
LUBRICATE THE HORIZONTAL
STABILIZER TRIM CONTROL SYSTEM
AND DO A STABILIZER BALLSCREW TO
BALLNUT FREEPLAY CHECK.
SERVICE ACCESS
DOOR (311AL)
N87426
Original Issue: August 07, 2003
Revision 1: January 20, 2010  BOEING PROPRIETARY -  757-27A0144
Copyright © Unpublished Work - See page 1 for details.  9 of 29

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757-27A0144Revision 1: January 20, 2010
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ALERTALERT
BLANK PAGE

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Commercial 
Airplanes
757
Service Bulletin
ALERT
Number: 757-27A0144
Original Issue: August 07, 2003
Revision 1: January 20, 2010
ATA System: 2741
SUBJECT: FLIGHT CONTROLS - Horizontal Stabilizer - Horizontal Stabilizer Trim Actuator -
Ballscrew Freeplay Check Addition and Lubrication Interval Change
THIS BULLETIN IS SENT TO THE OPERATORS OF RECORD OF THE AIRPLANES SHOWN IN PARAGRAPH
1.A., EFFECTIVITY. IF AN AIRPLANE HAS BEEN LEASED OR SOLD, SEND THIS SERVICE BULLETIN TO
THE NEW OPERATOR. IF APPLICABLE SPARES HAVE BEEN SOLD, SEND THIS SERVICE BULLETIN TO
THE NEW OWNER.
1.    PLANNING INFORMATION
A. Effectivity
1. Airplanes
Refer to Service Bulletin Index Document D624N001 Part 3 for Airplane Variable Number, Line
Number, and Serial Number data.
This service bulletin is for the airplanes shown below.
DESCRIPTIONCONFIGURATIONGROUP
All 757-200, 200CB, -200PF airplanes.-1
Airplanes that have not done an overhaul of the stabilizer trim actuator
in accordance with Service Bulletin 757-27A0142 and have less than
or equal to 15,000 total flight hours.
1
Airplanes that have not done an overhaul of the stabilizer trim actuator
in accordance with Service Bulletin 757-27A0142 and have more
than 15,000 total flight hours.
2
Airplanes that have done an overhaul of the stabilizer trim actuator
in accordance with Service Bulletin 757-27A0142.
3
Airplane Models:
757-200, 757-200CB, 757-200PF
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GroupVariable Number
1NA001 - NA028
1NA191 - NA199
1NA201 - NA239
1NA301 - NA305
1NA341 - NA352
1NA391 - NA399
1NA401 - NA408
1NA441 - NA447
1NA501 - NA586
1NB001 - NB004
1NB021 - NB023
1NB036 - NB041
1NB051 - NB053
1NB061 - NB073
1NB079
1NB131 - NB148
1NB161 - NB162
1NB166 - NB168
1NB201 - NB204
1NB221 - NB228
1NB230
1NB236
1NB239
1NB261 - NB267
1NB291 - NB299
1NB301 - NB302
1NB311 - NB312
1NB321 - NB331
1NB421 - NB438
1NB446
1NB451 - NB454
1NB501 - NB523
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GroupVariable Number
1NB561
1NB571
1NB581 - NB583
1NC001 - NC033
1NC041 - NC042
1NC051 - NC052
1NC056 - NC062
1NC066 - NC084
1NC091 - NC094
1NC151
1NC161
1NC901 - NC951
1NC971 - NC974
1ND001 - ND007
1ND011 - ND059
1ND111 - ND113
1ND161 - ND199
1ND201 - ND203
1ND221 - ND225
1ND241 - ND248
1ND301 - ND322
1ND401
1ND891
1ND895
1NE001 - NE008
1NE011 - NE088
1NE091 - NE094
1NE141 - NE150
1NE161 - NE177
1NE201 - NE204
1NE301 - NE302
1NE311 - NE325
1NJ001 - NJ004
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GroupVariable Number
1NJ031 - NJ032
1NJ551 - NJ555
1NN001 - NN002
1NN051 - NN052
1NP901 - NP904
1NS601 - NS616
1NT001 - NT009
1NT201 - NT202
1NT231 - NT234
1NT237 - NT240
1NT242
1NT245 - NT248
1NT281 - NT289
1NT341 - NT347
1NT351 - NT360
1NT371 - NT373
1NT375 - NT379
1NT381 - NT386
1NT401 - NT409
1NT411 - NT412
1NT426 - NT427
1NT431 - NT432
1NT436 - NT438
1NT441 - NT442
1NT446
1NT701 - NT769
1NT791 - NT796
1NT861 - NT862
1NT881 - NT885
1NT901 - NT916
1NT971 - NT985
1NU031 - NU038
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2. Spares Affected
None.
B. Concurrent Requirements
None.
C. Reason
This service bulletin is being issued to provide a new stabilizer ballscrew lubrication interval and detailed
inspection interval. Also, a new stabilizer ballscrew to ballnut freeplay check is included with a
recommended check interval. The inspections/check are an added level of protection which reduces
the potential of unlikely failure modes of the stabilizer ballscrew assembly used on the stabilizer actuator.
The inspections/check can be run in-situ on the airplane.
After an MD-80 horizontal stabilizer jackscrew incident, a design review was initiated of the Boeing
heritage horizontal stabilizer ballscrews. During this review, an operator reported a 757 horizontal
stabilizer ballscrew with extensive corrosion. An investigation was initiated. This investigation identified
that a maintenance procedure to check the stabilizer ballscrew primary load path was required. Loss
of the horizontal stabilizer ballscrew primary and secondary load paths, although extremely improbable,
could potentially result in the loss of control of the airplane.
Boeing Service Related Problem (SRP) 757-SRP-27-0153 is related to this service bulletin.
NOTE: Service Bulletin 757-27-0137 served as an interim maintenance action related to
757-SRP-27-0153. Service Bulletin 757-27A0144 is the final maintenance recommendation
related to 757-SRP-27-0153. Upon release of Service Bulletin 757-27A0144, operators should
perform the maintenance actions in that bulletin rather than those in Service Bulletin
757-27-0137. However, it should be noted that Service Bulletin 757-27-0137 includes one
maintenance action that is not included in Service Bulletin 757-27A0144: lubrication of the
stabilizer pivot hinges. Lubrication of the stabilizer pivot hinges was included in Service Bulletin
757-27-0137 as a convenience; it is unrelated to the safety issue addressed in safety
757-SRP-27-0153. Boeing recommends that operators continue to perform the stabilizer hinge
lubrication task per 757 MPD Volume 1 Section 5, and 757 AMM 12-21-05.
Revision 1 is sent to change the compliance times of the detailed inspection, lubrication and
ballnut-to-ballscrew freeplay check. Instructions on how to accomplish the detailed inspection are
replaced by an instruction to do the detailed inspection in accordance with the Aircraft Maintenance
Manual (AMM) and Part 3 is added to the work instructions to give lubrication instructions. Revision 1
also adds an Airworthiness Directive (AD) statement and removes all figures as the procedures are
now accomplished by the AMM.
These sections were changed:
1. Summary:
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757-27A0144Revision 1: January 20, 2010
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BOEING SERVICE BULLETIN 757-27A0144
ALERTALERT

### Page 16

– Background: A interim notification of a revision to the Maintenance Planning Document (MPD)
statement is removed.
– Action: The statement is updated to agree with the updated work instructions.
– Compliance: An Airworthiness Directive (AD) statement is added.
– Manpower: The manpower table is removed.
– Illustration: The summary illustration paragraph is updated.
2. Planning Information:
– Paragraph 1.A., Effectivity: A group configuration table is added which splits the effectivity
into 3 configurations.
– Paragraph 1.C., Reason: A interim notification of a revision to the Maintenance Planning
Document (MPD) statement is removed.
– Paragraph 1.D., Description: The statement is updated to agree with the updated work
instructions and maintenance zones are added.
– Paragraph 1.E., Compliance: An Airworthiness Directive (AD) statement is added.
– Paragraph 1.E., Compliance: The compliance times and repeat intervals for the detailed
inspection, lubrication and freeplay check in Tables 1 and 2 are changed. The corrective action
for damaged parts is added, footnotes (a) and (b) are changed and footnote (c) is deleted.
– Paragraph 1.E., Compliance: The compliance times and repeat intervals for the detailed
inspection, lubrication and freeplay check in Table 3 are changed. The corrective action for
damaged parts is added, footnotes (a) and (b) are changed and footnotes (c) and (d) are
deleted.
– Paragraph 1.G., Manpower: The manpower table is updated.
3. Accomplishment Instructions:
– Paragraph 3.B., Work Instructions: A note is deleted from Part 1, Step 1 and the access,
cleaning, lubrication and detailed inspection instructions are replaced by one instruction to do
a detailed inspection in accordance with the AMM.
– Paragraph 3.B., Work Instructions: The access instruction is removed from Part 2 and an
AMM task is added to the instruction to do the stabilizer ballscrew to ballnut freeplay check.
– Paragraph 3.B., Work Instructions: Part 3 is added to give lubrication instructions.
– Figure 1: This Figure is deleted.
– Figure 2: This Figure is deleted.
– Figure 3: This Figure is deleted.
D. Description
Get access to the horizontal stabilizer trim ballscrew actuator and do the procedures that follow below
at the intervals shown in Paragraph 1.E., Compliance:
– Do a detailed inspection of the stabilizer ballscrew assembly.
– Lubricate the horizontal stabilizer trim control system.
– Do a stabilizer ballscrew to ballnut freeplay check.
– Replace damaged and/or cracked and/or worn stabilizer trim ballscrew actuators.
Revision 1 - No more work is necessary on airplanes changed in accordance with the original issue of
this service bulletin. However, operators must continue to do the repeat detailed inspection, lubrication
and freeplay check in accordance with Paragraph 1.E., Compliance.
The work in this service bulletin is done in the maintenance zone(s) given below.
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Affected Maintenance Zones
ZoneModel
311, 312757-200, 757-200CB, 757-
200PF
E. Compliance
The Federal Aviation Administration (FAA) will possibly release an Airworthiness Directive related to
this service bulletin. The Airworthiness Directive will make the compliance tasks and times given in this
service bulletin mandatory.
Group 1, Configuration 1:
Table 1: All airplanes that have not done the overhaul of the stabilizer trim actuator in accordance with
Service Bulletin 757-27A0142 and have completed less than or equal to 15,000 flight hours.
Repeat Interval (Not to Ex-
ceed, Whichever Occurs
First)
Compliance Time (Whichev-
er Occurs First)
ActionCondition
2 years.3,500 flight
hours.
Within 2 years
from the last
detailed in-
spection.
Within 3,500
flight hours
from the last
detailed in-
spection.
Detailed inspection of
the stabilizer ballscrew
assembly in accor-
dance with Paragraph
3.B., Work Instructions,
Part 1.
All airplanes that have
not done the overhaul
of the stabilizer trim ac-
tuator in accordance
with Service Bulletin
757-27A0142 and have
completed less than or
equal to 15,000 flight
hours.
1 year.2,000 flight
hours.
Within 1 year
from the last
lubrication.
Within 2,000
flight hours
from the last
lubrication.
Lubricate the horizontal
stabilizer trim control
system in accordance
with Paragraph 3.B.,
Work Instructions, Part
3. (a)
5 years.18,000 flight
hours.
If the Airplane will complete
15,000 total flight hours within
18 months from the date on
Revision 1 of this service bul-
letin, do the freeplay check
within 18 months.
Stabilizer ballscrew to
ballnut freeplay check
in accordance with
Paragraph 3.B., Work
Instructions, Part 2. (b)
If the Airplane completes less
than 15,000 total flight hours
within 18 months from the date
on Revision 1 of this service
bulletin, do the freeplay check
within 15,000 total flight hours
or 5 years, whichever occurs
first.
-Before further flight.Replace the stabilizer
trim ballscrew actuator.
Damage and/or cracks
and/or excessive wear
found on the stabilizer
trim ballscrew actuator.
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### Page 18

Group 1, Configuration 1:
Table 1: All airplanes that have not done the overhaul of the stabilizer trim actuator in accordance with
Service Bulletin 757-27A0142 and have completed less than or equal to 15,000 flight hours.
Repeat Interval (Not to Ex-
ceed, Whichever Occurs
First)
Compliance Time (Whichev-
er Occurs First)
ActionCondition
(a) Lubrication is accomplished as a part of either the detailed inspection or the freeplay check.
(b) If the detailed inspection and the freeplay check are to be accomplished at the same time, do the detailed
inspection before the freeplay check.
Group 1, Configuration 2:
Table 2: All airplanes that have not done the overhaul of the stabilizer trim actuator in accordance with
Service Bulletin 757-27A0142 and have completed more than 15,000 flight hours.
Repeat Interval (Not to Ex-
ceed, Whichever Occurs
First)
Compliance Time (Whichev-
er Occurs First)
ActionCondition
2 years.3,500 flight
hours.
Within 18
months from
the last de-
tailed inspec-
tion.
Within 3,500
flight hours
from the last
detailed in-
spection.
Detailed inspection of
the stabilizer ballscrew
assembly in accor-
dance with Paragraph
3.B., Work Instructions,
Part 1.
All airplanes that have
not done the overhaul
of the stabilizer trim ac-
tuator in accordance
with Service Bulletin
757-27A0142 and have
completed more than
15,000 flight hours. 1 year.2,000 flighthours.Within 1 yearfrom the last
lubrication.
Within 2,000
flight hours
from the last
lubrication.
Lubricate the horizontal
stabilizer trim control
system in accordance
with Paragraph 3.B.,
Work Instructions, Part
3. (a)
5 years.18,000 flight
hours.
Within 18
months after
the date on
Revision 1 of
this service
bulletin.
-Stabilizer ballscrew to
ballnut freeplay check
in accordance with
Paragraph 3.B., Work
Instructions, Part 2. (b)
-Before further flight.Replace the stabilizer
trim ballscrew actuator.
Damage and/or cracks
and/or excessive wear
found on the stabilizer
trim ballscrew actuator.
(a) Lubrication is accomplished as a part of either the detailed inspection or the freeplay check.
(b) If the detailed inspection and the freeplay check are to be accomplished at the same time, do the detailed
inspection before the freeplay check.
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### Page 19

Group 1, Configuration 3:
Table 3: All airplanes that have done the overhaul of the stabilizer trim actuator in accordance with
Service Bulletin 757-27A0142.
Repeat Interval (Not to Ex-
ceed, Whichever Occurs
First)
Compliance Time (Whichev-
er Occurs First)
ActionCondition
2 years.3,500 flight
hours.
Within 2 years
from the last
detailed in-
spection.
Within 3,500
flight hours
from the last
detailed in-
spection.
Detailed inspection of
the stabilizer ballscrew
assembly in accor-
dance with Paragraph
3.B., Work Instructions,
Part 1.
All airplanes that have
done the overhaul of
the stabilizer trim actua-
tor in accordance with
Service Bulletin 757-
27A0142.
1 year.2,000 flight
hours.
Within 1 year
from the last
lubrication.
Within 2,000
flight hours
from the last
lubrication.
Lubricate the horizontal
stabilizer trim control
system in accordance
with Paragraph 3.B.,
Work Instructions, Part
3. (a)
5 years.18,000 flight
hours.
If the Airplane will complete
15,000 total flight hours since
overhaul within 18 months from
the date on Revision 1 of this
service bulletin, do the freeplay
check within 18 months.
Stabilizer ballscrew to
ballnut freeplay check
in accordance with
Paragraph 3.B., Work
Instructions, Part 2. (b)
If the Airplane completes less
than 15,000 total flight hours
since overhaul within 18
months from the date on Revi-
sion 1 of this service bulletin,
do the freeplay check within
15,000 total flight hours or 5
years, whichever occurs first.
-Before further flight.Replace the stabilizer
trim ballscrew actuator.
Damage and/or cracks
and/or excessive wear
found on the stabilizer
trim ballscrew actuator.
(a) Lubrication is accomplished as a part of either the detailed inspection or the freeplay check.
(b) If the detailed inspection and the freeplay check are to be accomplished at the same time, do the detailed
inspection before the freeplay check.
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BOEING SERVICE BULLETIN 757-27A0144
ALERTALERT

### Page 20

F. Approval
This service bulletin was examined by the Federal Aviation Administration (FAA). The changes specified
in this service bulletin comply with the applicable regulations and are FAA approved, as well as European
Aviation Safety Agency (EASA)/Joint Aviation Authorities (JAA) approved for all EASA/JAA approved
airplanes listed in the service bulletin effectivity. This service bulletin and its approval were based on
the airplane in its original Boeing delivery configuration or as modified by other approved Boeing
changes.
If an airplane has a non-Boeing modification or repair that affects a component or system also affected
by this service bulletin, the operator is responsible for obtaining appropriate regulatory agency approval
before incorporating this service bulletin.
G. Manpower
The table below shows an estimate of the task-hours necessary to do the detailed inspection, lubrication
and freeplay check for each airplane. This estimate is for direct labor only, done by an experienced
crew. Adjust the estimate with operator task-hour data if necessary. The estimate does not include lost
time. These are some examples of lost time:
— Time to adjust to the workplace
— Time to schedule the work
— Time to examine the work
— Time to cure the materials
— Time to make the parts
— Time to find the tools.
Elapsed HoursTask-HoursNumber of Per-
sons
Task
2.004.002Part 1 - Detailed Inspec-
tion
3.006.002Part 2 - Freeplay Check
1.503.002Part 3 - Lubrication
(a)(a)TOTAL FOR EACH AIRPLANE
(a) The total task-hours and elapsed hours are not given as the Parts accomplished
at the same time are variable.
H. Weight and Balance Changes
None.
I. Electrical Load Data
Not changed.
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### Page 21

J. References
1. Existing Data:
a. Boeing Service Bulletin 757-27-0137, 757-27A0142
b. Boeing Service Related Problem (SRP) 757-SRP-27-0153
c. 757 Aircraft Maintenance Manual (AMM) 12-21-05, 27-41-10
d. 757 Maintenance Planning Data (MPD) 757 MPD Volume 1 Section 5
2. Data supplied with this Service Bulletin:
None.
3. Installation Drawings Used in the Preparation of this Service Bulletin:
None.
K. Publications Affected
Chapter-SectionPublication
27-41757 Aircraft Maintenance Manual
L. Interchangeability and Intermixability of Parts
Accomplishment of this service bulletin does not affect interchangeability or intermixability of parts.
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### Page 22

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BLANK PAGE

### Page 23

2.    MATERIAL INFORMATION
A. Material - Price and Availability
None.
B. Industry Support Information
Boeing warranty remedies are not available for the inspections/check given in this service bulletin.
C. Parts Necessary For Each Airplane
1. Kits/Parts:
None.
2. Parts and Materials Supplied by the Operator:
None.
3. Parts Modified and Reidentified:
None.
4. Parts Removed and Not Replaced:
None.
D. Parts Necessary to Change Spares
None.
E. Special Tooling - Price and Availability
None.
F. Special Tooling Necessary to do this Service Bulletin
No special tools or equipment are necessary to do the change in this service bulletin. But, maintenance
and overhaul tools in the manuals given in Paragraph 1.J., References, can be necessary. Examine
operator tool supply to make sure all necessary tools are available.
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### Page 24

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BLANK PAGE

### Page 25

3.    ACCOMPLISHMENT INSTRUCTIONS
A. GENERAL INFORMATION
CAUTION: KEEP THE WORK AREA, WIRES AND ELECTRICAL BUNDLES CLEAN OF METAL
PARTICLES OR CONTAMINATION WHEN YOU USE TOOLS. UNWANTED MATERIAL,
METAL PARTICLES OR CONTAMINATION CAUGHT IN WIRE BUNDLES CAN CAUSE
DAMAGE TO THE BUNDLES. DAMAGED WIRE BUNDLES CAN CAUSE SPARKS OR
OTHER ELECTRICAL DAMAGE.
NOTE: 1. The instructions identified in Paragraph 3.B., Work Instructions and the Figure(s)
give the recommended sequence of steps. The sequence of steps to do this service
bulletin can be changed.
2. Manual titles are referred to by acronyms. Refer to Paragraph 1.J., References, for
definition of the acronyms.
3. Obey all of the warnings and cautions given in the specified manual sections.
4. Unless shown differently, these dimensions and tolerances are used:
– Linear dimensions are in inches
– Tolerance on linear dimensions, other than rivet and bolt edge margins, is plus
or minus 0.03 inch
5. A Detailed Inspection is defined as: An intensive examination of a specific item,
installation, or assembly to detect damage, failure, or irregularity. Available lighting
is normally supplemented with a direct source of good lighting at an intensity deemed
appropriate. Inspection aids such as mirrors, magnifying lenses, etc. may be
necessary. Surface cleaning and elaborate procedures may be required.
6. These work instructions refer to procedures included in other Boeing documents.
When the words "refer to" are used and the operator has an accepted alternative
procedure, the accepted alternative procedure can be used. When the words "in
accordance with" are included in the instruction, the procedure in the Boeing document
must be used.
B. WORK INSTRUCTIONS
PART 1 : Stabilizer Ballscrew Assembly Detailed Inspection:
1. Do a detailed inspection of the stabilizer ballscrew assembly in accordance with 757 AMM 27-41-10.
2. Put the airplane back to a serviceable condition.
PART 2 : Stabilizer Ballscrew to Ballnut Freeplay Check:
1. Do a stabilizer ballscrew to ballnut freeplay check in accordance with 757 AMM 27-41-10.
2. Put the airplane back to a serviceable condition.
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BOEING SERVICE BULLETIN 757-27A0144
ALERTALERT

### Page 26

Part 3: Horizontal Stabilizer Trim Control System Lubrication
1. Lubricate the horizontal stabilizer trim control system in accordance with 757 AMM 12-21-05.
2. Put the airplane back to a serviceable condition.
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ALERTALERT

### Page 27 (OCR)

BOEING SERVICE BULLETIN 757-27A0144
ALERT  ALERT
THIS FIGURE IS DELETED.
D38438
FIGURE 1: INSPECTION OF HORIZONTAL STABILIZER BALLSCREW LOAD PATH
(SHEET 1 OF 1)
Devision Jai: any 20, 201003  BOEING PROPRIETARY -  757-27A0144
Copyright © Unpublished Work - See page 1 for details.  27 of 29

### Page 28 (OCR)

BOEING SERVICE BULLETIN 757-27A0144
ALERT  ALERT
THIS FIGURE IS DELETED.
FIGURE 2: HORIZONTAL STABILIZER BALLSCREW AND BALLNUT FREEPLAY CHECK
(SHEET 1 OF 1)
Original Issue: August 07, 2003
Revision 1 January 20, 2010  BOEING PROPRIETARY -  757-27A0144
Copyright © Unpublished Work - See page 1 for details.  28 of 29

### Page 29 (OCR)

BOEING SERVICE BULLETIN 757-27A0144
ALERT  ALERT
THIS FIGURE IS DELETED.
D38438
FIGURE 3: HORIZONTAL STABILIZER TRIM BALLSCREW ACTUATOR REPLACEMENT
(SHEET 1 OF 1)
Devision Jai any 20, 201003  OEING PROPRIETARY  757-27A0144
opyright © Unpublished Work - See page 1 for detai  29 of 29

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