# Boeing Alert Requirements Bulletin 757-27A0159 RB: Revision 1

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- Title as filed: 757-27A0159 RB_R1
- Pages: 23
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### Page 1

Commercial 
Airplanes
757
Requirements Bulletin
ALERT
Number: 757-27A0159 RB
Original Issue: March 29, 2019
Revision 1: April 29, 2020
ATA System: 2711
SUBJECT: FLIGHT CONTROLS - Aileron and Aileron Trim Control System - Aileron Trim Actuator
Bearing Rotation Check and Attachment Lug Inspections
Export of this technology is controlled under the United States Export Administration Regulations (EAR) (15
CFR 300-774). An export license may be required before it is used for development, production or use by foreign
persons from specific countries. The controller of this data has the individual responsibility to abide by all export
laws.
9E991ECCN:
Copyright © 2019 Boeing.
Unpublished Work. All Rights Reserved.
Treatment of this document and its content is governed by contract with Boeing. Rights to use this document
are licensed on a per aircraft basis and such rights may not be transferable. For more information, contact The
Boeing Company.
Boeing, the Boeing signature, the Boeing symbol, 707, 717, 727, 737, 747, 757, 767, 777, 787, Dreamliner,
BBJ, DC-8, DC-9, DC-10, KC-10, KC-46, KDC-10, MD-10, MD-11, MD-80, MD-88, MD-90, P-8, Poseidon and
Boeing liveries are all trademarks owned by The Boeing Company; and no trademark license is granted in
connection with this document unless provided in writing by Boeing.
Original Issue: March 29, 2019
757-27A0159 RBRevision 1: April 29, 2020
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3.0

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Table of Contents
Revision Transmittal Sheet . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
1. EFFECTIVITY . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
A. Airplanes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
B. Spares Affected . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
2. CONCURRENT REQUIREMENTS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
3. COMPLIANCE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
4. APPROVAL . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
5. ACCOMPLISHMENT INSTRUCTIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
A. General Inf ormation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
B. Work Instructions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
FIGURE 2: MAIN LANDING GEAR WHEEL WELL - AILERON TRIM ACTUATOR BEARING - ROTATION
CHECK . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18
FIGURE 3: MAIN LANDING GEAR WHEEL WELL - AILERON TRIM ACTUATOR ATTACHMENT LUG -
DETAILED INSPECTION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20
FIGURE 4: MAIN LANDING GEAR WHEEL WELL - AILERON TRIM ACTUATOR ATTACHMENT LUG -
HIGH FREQUENCY EDDY CURRENT (HFEC) INSPECTION . . . . . . . . . . . . . . . 22
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Commercial 
Airplanes
757
Requirements Bulletin
ALERT
Revision Transmittal SheetNumber: 757-27A0159 RBOriginal Issue: March 29, 2019
Revision 1: April 29, 2020
ATA System: 2711
SUBJECT: FLIGHT CONTROLS - Aileron and Aileron Trim Control System - Aileron Trim Actuator
Bearing Rotation Check and Attachment Lug Inspections
This revision includes all pages of the requirements bulletin.
COMPLIANCE INFORMATION RELATED TO THIS REVISION
Federal Aviation Administration (FAA) Airworthiness Directive AD 2019-12-13 is related to Requirements Bulletin
757-27A0159 RB.
Effects of this Revision on airplanes on which the Original Issue of Requirements Bulletin 757-27A0159 RB was
previously done:
None.
REASON FOR REVISION
This revision is sent to add the correct approval statement for 757-200CB airplanes.This revision also incorporates
changes requested by operators. The changes affect the parts necessary to do the changes and Figures in the
service bulletin. In addition, reference to Federal Aviation Administration (FAA) Airworthiness Directive AD
2019-12-13 has been added.
These sections were changed:
- In Compliance - Added Federal Aviation Administration (FAA) Airworthiness Directive AD 2019-12-13. Changed
the compliance time limits.
- In Approval of the Requirements Bulletin - Added approval statement for 757-200CB airplanes and note to
clarify approval statement for all airplanes except 757-200CB airplanes. Also added Alternative Method Of
Compliance (AMOC) data.
Vertical lines are put on the left edge of each page, except in Paragraph 1.A., Effectivity and format changes,
to show the location of all content changes.
Pages with no vertical lines have no changes.
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REVISION HISTORY
Service BulletinService BulletinRequirement BulletinRequirement Bulletin
757-27A0159757-27A0159757-27A0159 RB757-27A0159 RB
Issue DateIssue Date
March 29, 2019Original Issue:March 29, 2019Original Issue:
April 29, 2020Revision 1:April 29, 2020Revision 1:
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REQUIREMENTS BULLETIN 757-27A0159
ALERTALERT

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Commercial 
Airplanes
757
Requirements Bulletin
ALERT
Number: 757-27A0159 RB
Original Issue: March 29, 2019
Revision 1: April 29, 2020
ATA System: 2711
SUBJECT: FLIGHT CONTROLS - Aileron and Aileron Trim Control System - Aileron Trim Actuator
Bearing Rotation Check and Attachment Lug Inspections
THIS DOCUMENT 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 DOCUMENT
TO THE NEW OPERATOR. IF APPLICABLE SPARES HAVE BEEN SOLD, SEND THIS DOCUMENT TO THE
NEW OWNER. THIS IS AN ENHANCED REQUIRED FOR COMPLIANCE DOCUMENT. THE BOEING
PROCESSES USED TO CREATE THE SERVICE BULLETIN (SB) AND THE REQUIREMENTS BULLETIN
(RB) ENSURE THAT THE INFORMATION BETWEEN "RC START" AND "RC END" IN THE SB ARE IDENTICAL
TO THE INFORMATION IN THE SAME SECTIONS (COMPLIANCE, WORK INSTRUCTIONS…) OF THE RB
WHICH THE SB REFERS TO AS THE RELATED DOCUMENT.
1. Effectivity
A. Airplanes
This bulletin is applicable to 757-200, 757-200CB, 757-200PF, 757-300 Airplane(s), line number(s)
1-1050 in 1 Group(s). Where the effectivity is presented with hyphens between line numbers, the
airplane applicability means "through" and "inclusive", e.g. line numbers 1-9 means line numbers
1 through 9 inclusive.
The Variable Numbers and Group Information for the applicable airplanes is given below.
DESCRIPTIONCONFIGURATIONGROUP
All 757 airplanes.-1
Airplane Models:
757-200, 757-200CB, 757-200PF, 757-300
GroupVariable Number
1NA001 - NA028
1NA191 - NA199
1NA201 - NA239
1NA301 - NA305
GroupVariable Number
1NA341 - NA352
1NA391 - NA399
1NA401 - NA408
1NA441 - NA447
GroupVariable Number
1NA501 - NA586
1NB001 - NB004
1NB021 - NB023
1NB036 - NB041
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GroupVariable Number
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
1NB561
1NB571
1NB581 - NB583
1NC001 - NC033
1NC041 - NC042
1NC051 - NC052
1NC056 - NC062
1NC066 - NC084
1NC091 - NC094
1NC151
1NC161
GroupVariable Number
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
1NJ031 - NJ032
1NJ551 - NJ555
1NL001 - NL002
1NL006 - NL017
1NL101 - NL109
1NL141
1NL601 - NL616
1NN001 - NN002
1NN051 - NN052
GroupVariable Number
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
1NU701 - NU705
1NU721 - NU728
1NU731 - NU732
B. Spares Affected
Examine your spares supply for the parts or components identified below. If any parts or components
are found, refer to the Accomplishment Instructions for the recommended action.
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NamePart Number
AILERON TRIM ACTUATOR60B80030-3 OR -4 (SHIMADZU PART
NUMBER 732-16810-01 OR -03)
2. CONCURRENT REQUIREMENTS
None.
3. COMPLIANCE
Federal Aviation Administration (FAA) Airworthiness Directive AD 2019-12-13 is related to Requirements
Bulletin 757-27A0159 RB. The effective date of AD 2019-12-13 is July 12, 2019.
Accomplish the required actions, based on the applicable conditions in Tables 1 and 2 in accordance with
the Accomplishment Instructions.
When more than one OPTION is given for a CONDITION, do only one of the OPTION numbers. When
more than one ACTION is given for a CONDITION or an OPTION, do all of the ACTION numbers for that
CONDITION or OPTION.
Table 1: Aileron Trim Actuator Bearing Rotation Check
Repeat Interval
(Not to Exceed)
Compliance TimeActionCondition
-Within 1,760 Flight
Hours after the ef-
fective date of AD
2019-12-13.
Do an Aileron Trim Actua-
tor bearing rotation check
to make sure it turns
freely. (a)
All Airplanes
-Before further
flight.
Do a HFEC inspection of
the Aileron Trim Actuator
attachment lug for any
crack. (c)
CONDITION 1: BEARING
DOES NOT TURN
FREELY.
-Before further
flight.
CONDITION 1.1 (AC-
TION 1): Contact the
Boeing Company for re-
pair instructions and do
the repair.
CONDITION 1.1: ANY
CRACK IS FOUND DUR-
ING THE HFEC INSPEC-
TION OF THE AILERON
TRIM ACTUATOR AT-
TACHMENT LUG -Before further
flight.
CONDITION 1.1 (AC-
TION 2): Replace the
Aileron Trim Actuator with
a new or serviceable part.
(b)
1,100 Flight Hours.-CONDITION 1.1 (AC-
TION 3): Repeat Aileron
Trim Actuator bearing ro-
tation check to make sure
it turns freely. (a)
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Table 1: Aileron Trim Actuator Bearing Rotation Check
Repeat Interval
(Not to Exceed)
Compliance TimeActionCondition
-.Before further
flight.
CONDITION 1.2 (AC-
TION 1): Replace the
Aileron Trim Actuator with
a new or serviceable part.
(b)
CONDITION 1.2: NO
CRACK IS FOUND DUR-
ING THE HFEC INSPEC-
TION OF THE AILERON
TRIM ACTUATOR AT-
TACHMENT LUG 1,100 Flight Hours.-CONDITION 1.2 (AC-
TION 2): Repeat Aileron
Trim Actuator bearing ro-
tation check to make sure
it turns freely. (a)
1,100 Flight Hours.-Repeat Aileron Trim Actu-
ator bearing rotation
check to make sure it
turns freely. (a)
CONDITION 2: BEARING
TURNS FREELY.
(a) A bearing that turns freely is defined as: A bearing that moves without ratchet, gritty, or
detent like feeling.
(b) The existing Aileron Trim Actuator can be replaced with a new or serviceable Aileron Trim
Actuator. A serviceable Aileron Trim Actuator is one with a bearing that turns freely.
(c) If a HFEC inspection of the Aileron Trim Actuator attachment lug for any crack is found to
be required as an action for both CONDITION 1 and CONDITION 3, the HFEC inspection
is only required to be done once before further flight.
Table 2: Detailed Inspection of the Aileron Trim Actuator Attachment Lug
Repeat Interval
(Not to Exceed)
Compliance TimeActionCondition
-Within 1,760 Flight
Hours after the ef-
fective date of AD
2019-12-13.
Do a Detailed Inspection
of the Aileron Trim Actua-
tor attachment lug for any
damage and any crack.
(a)
All Airplanes
-Before further
flight.
Do a HFEC inspection of
the Aileron Trim Actuator
attachment lug for any
crack. (b)
CONDITION 3: ANY DAM-
AGE OR ANY CRACK IS
FOUND DURING THE
DETAILED INSPECTION
OF THE AILERON TRIM
ACTUATOR ATTACH-
MENT LUG
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Table 2: Detailed Inspection of the Aileron Trim Actuator Attachment Lug
Repeat Interval
(Not to Exceed)
Compliance TimeActionCondition
-Before further
flight.
CONDITION 3.1 (AC-
TION 1): Contact the
Boeing Company for re-
pair instructions and do
the repair.
CONDITION 3.1: ANY
CRACK IS FOUND DUR-
ING THE HFEC INSPEC-
TION OF THE AILERON
TRIM ACTUATOR AT-
TACHMENT LUG 1,100 Flight Hours.-CONDITION 3.1 (AC-
TION 2): Repeat Detailed
Inspection of the Aileron
Trim Actuator attachment
lug for any damage and
any crack. (a)
1,100 Flight Hours.-Repeat Detailed Inspec-
tion of the Aileron Trim
Actuator attachment lug
for any damage and any
crack. (a)
CONDITION 3.2: NO
CRACK IS FOUND DUR-
ING THE HFEC INSPEC-
TION OF THE AILERON
TRIM ACTUATOR AT-
TACHMENT LUG
1,100 Flight Hours.-Repeat Detailed Inspec-
tion of the Aileron Trim
Actuator attachment lug
for any damage and any
crack. (a)
CONDITION 4: NO DAM-
AGE AND NO CRACK IS
FOUND DURING THE
DETAILED INSPECTION
OF THE AILERON TRIM
ACTUATOR ATTACH-
MENT LUG
(a) Damage is defined as: Any surface problems, such as scratches or dings, which have
occurred after the part was manufactured.
(b) If a HFEC inspection of the Aileron Trim Actuator attachment lug for any crack is found to
be required as an action for both CONDITION 1 and CONDITION 3, the HFEC inspection
is only required to be done once before further flight.
4. APPROVAL
NOTE: The approval statement that follows is valid for 757-200CB airplanes.
This Requirements Bulletin was examined by the Federal Aviation Administration (FAA). The changes
specified in this document comply with the applicable regulations and are FAA approved for all airplanes
listed in the Requirements Bulletin effectivity. This document 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 Requirements Bulletin, the operator is responsible for obtaining appropriate regulatory agency approval
before incorporating this Requirements Bulletin.
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In addition, the Manager of the FAA Los Angeles ACO Branch approves accomplishment of the inspection
and replacement defined in this Requirements Bulletin revision, as an alternative method of compliance to
the requirements of paragraph (g) of FAA Airworthiness Directive (AD) 2019-12-13. All provisions of FAA
AD 2019-12-13 that are not specifically referenced in the above statement remain fully applicable and must
be complied with accordingly.
NOTE: The approval statement that follows is valid for all affected airplanes, except 757-200CB airplanes.
This Requirements Bulletin was examined by the Federal Aviation Administration (FAA). The changes
specified in this document 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 Requirements Bulletin effectivity. This document and its approval were based on the
airplane in its original Boeing delivery configuration or as modified by other Boeing changes.
If an airplane has a non-Boeing modification or repair that affects a component or system also affected by
this Requirements Bulletin, the operator is responsible for obtaining appropriate regulatory agency approval
before incorporating this Requirements Bulletin.
In addition, the Manager of the FAA Los Angeles ACO Branch approves accomplishment of the inspection
and replacement defined in this Requirements Bulletin revision, as an alternative method of compliance to
the requirements of paragraph (g) of FAA Airworthiness Directive (AD) 2019-12-13. All provisions of FAA
AD 2019-12-13 that are not specifically referenced in the above statement remain fully applicable and must
be complied with accordingly.
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5.    ACCOMPLISHMENT INSTRUCTIONS
A. GENERAL INFORMATION
NOTE: 1. This is an Enhanced Required for Compliance document. There will be a separate
Service Bulletin (SB) and a separate Requirements Bulletin (RB). If an RB is mandated
by an Airworthiness Directive (AD), then all applicable requirements specified in the
RB must be done. For the related SB, some locations are marked RC Start and RC
End to identify the requirements that are restated from the RB. For the related SB,
the areas between RC Start and RC End, including sub-steps and any figures
identified between RC Start and RC End, must be done to comply with the AD.
Therefore, an Alternative Method of Compliance (AMOC) is required for any deviations
to steps between RC Start and RC End, including substeps and identified figures.
For the related SB, the steps not between RC Start and RC End may be deviated
from using accepted methods in accordance with the operator's maintenance or
inspection program without obtaining approval of an AMOC; this is provided that the
steps between RC Start and RC End, including sub-steps and identified figures, can
still be done as specified, and the airplane can be put back in an airworthy condition.
Figures not required for compliance are omitted from the RB.
2. This is an Enhanced Required for Compliance document. The Boeing processes
used to create the Service Bulletin (SB) and the Requirements Bulletin (RB) ensure
that the information between "RC Start" and "RC End" in the SB are identical to the
information in the same sections (Compliance, Work Instructions...) of the RB which
the SB refers to as the related document.
3. The compliance times for the actions in WORK INSTRUCTIONS are in Compliance.
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
– Tolerance on rivet and bolt edge margin is plus or minus 0.05 inch
– Angular tolerance is plus or minus 2 degrees
– Hole dimensions for standard solid rivets and fasteners are in Structural Repair
Manual (SRM) Chapter 51
– Torque Values:
— Values for structural fasteners are given in 757 Structural Repair Manual,
Chapter 51.
— Values for airframe maintenance tasks are included in Chapter 20 of 757
Aircraft Maintenance Manual (AMM).
— Values for electrical maintenance tasks are included in Chapter 20 of
Standard Wiring Practices Manual (SWPM).
— Values for engine maintenance tasks are included in Chapter 70 of 757
Aircraft Maintenance Manual (AMM).
— Non-standard torque values for maintenance tasks are included in the
applicable installation step.
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5. 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.
6. When more than one OPTION is given for a CONDITION, do only one of the OPTION
numbers. When more than one ACTION is given for a CONDITION or an OPTION,
do all of the ACTION numbers for that CONDITION or OPTION.
7. If the length of any fastener specified in this service bulletin does not meet installation
standards given in SRM Chapter 51, then a fastener of the same specification, or
an approved substitute, with a length which meets the installation standards given
in SRM Chapter 51 may be used. In addition, washers may be installed for fastener
grip length in accordance with SRM Chapter 51. Refer to SOPM 20-50-01 for alternate
full threaded fasteners (screws) needed for installation in this service bulletin.
8. The instructions in the Work Instructions and the figures can include operation of
tools or test equipment. Boeing Engineering Tool Drawings, the Illustrated Tool and
Equipment Manual, and the Special Tool and Ground Handling Drawing Index contain
data on versions of the tools or test equipment that you can use. It is permitted to
use replaced tools. It is not permitted to use superseded tools.
9. If it is necessary to remove more parts for access, you can remove those parts. If
you can get access without removing identified parts, it is not necessary to remove
all of the identified parts. Jacking and shoring limitations must be observed.
10. A Detailed Inspection is defined as: An intensive examination of a specific item,
installation or assembly to detect damage, failure or irregularity. This could include
tactile assessment in which a component or assembly can be checked for
tightness/security. Available lighting is normally supplemented with a direct source
of good lighting at an intensity deemed appropriate. Inspection aids such as mirrors
and magnifying lenses may be necessary. Surface cleaning and elaborate access
procedures may be required.
11. Use the approved fastener, process and material substitutions in accordance with
SRM Chapter 51.
12. Where the work instructions include installation of a kept part, a new or serviceable
part with the same part number can be installed as an alternative to the kept part.
B. WORK INSTRUCTIONS
Actions Required for Compliance:
1. Requirements
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Table 1: Aileron Trim Actuator Bearing Rotation Check
Refer to the listed
procedures in SB
757-27A0159
Original Issue or
later approved re-
visions as an ac-
cepted proce-
dure.
Method of Compli-
ance
ActionCondition
Do PART 1:
PREPARATION
-Do an Aileron Trim Actua-
tor bearing rotation check
to make sure it turns
freely. (a)
All Airplanes
-FIGURE 2
-FIGURE 4Do a HFEC inspection of
the Aileron Trim Actuator
attachment lug for any
crack. (c)
CONDITION 1: BEARING
DOES NOT TURN
FREELY
--CONDITION 1.1 (AC-
TION 1): Contact the
Boeing Company for re-
pair instructions and do
the repair.
CONDITION 1.1: ANY
CRACK IS FOUND DUR-
ING THE HFEC INSPEC-
TION OF THE AILERON
TRIM ACTUATOR AT-
TACHMENT LUG Do PART 2:
AILERON TRIM
ACTUATOR RE-
PLACEMENT
-CONDITION 1.1 (AC-
TION 2): Replace the
Aileron Trim Actuator with
a new or serviceable part.
(b)
Do PART 3:
RESTORATION
--
-FIGURE 2CONDITION 1.1 (AC-
TION 3): Repeat Aileron
Trim Actuator bearing ro-
tation check to make sure
it turns freely. (a)
Do PART 2:
AILERON TRIM
ACTUATOR RE-
PLACEMENT
-CONDITION 1.2 (AC-
TION 1): Replace the
Aileron Trim Actuator with
a new or serviceable part.
(b)
CONDITION 1.2: NO
CRACK IS FOUND DUR-
ING THE HFEC INSPEC-
TION OF THE AILERON
TRIM ACTUATOR AT-
TACHMENT LUG Do PART 3:
RESTORATION
--
-FIGURE 2CONDITION 1.2 (AC-
TION 2): Repeat Aileron
Trim Actuator bearing ro-
tation check to make sure
it turns freely. (a)
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757-27A0159 RBRevision 1: April 29, 2020
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REQUIREMENTS BULLETIN 757-27A0159
ALERTALERT

### Page 16

Table 1: Aileron Trim Actuator Bearing Rotation Check
Refer to the listed
procedures in SB
757-27A0159
Original Issue or
later approved re-
visions as an ac-
cepted proce-
dure.
Method of Compli-
ance
ActionCondition
Do PART 3:
RESTORATION
--CONDITION 2: BEARING
TURNS FREELY
-FIGURE 2Repeat Aileron Trim Actu-
ator bearing rotation
check to make sure it
turns freely. (a)
(a) A bearing that turns freely is defined as: A bearing that moves without ratchet, gritty, or
detent like feeling.
(b) The existing Aileron Trim Actuator can be replaced with a new or serviceable Aileron Trim
Actuator. A serviceable Aileron Trim Actuator is one with a bearing that turns freely.
(c) If a HFEC inspection of the Aileron Trim Actuator attachment lug for any crack is found to
be required as an action for both CONDITION 1 and CONDITION 3, the HFEC inspection
is only required to be done once before further flight.
Table 2: Detailed Inspection of the Aileron Trim Actuator Attachment Lug
Refer to the listed
procedures in SB
757-27A0159
Original Issue or
later approved re-
visions as an ac-
cepted proce-
dure.
Method of Compli-
ance
ActionCondition
Do PART 1:
PREPARATION
-Do a Detailed Inspection
of the Aileron Trim Actua-
tor attachment lug for any
damage and any crack.
(a)
All Airplanes
-FIGURE 3
-FIGURE 4Do a HFEC inspection of
the Aileron Trim Actuator
attachment lug for any
crack. (b)
CONDITION 3: ANY DAM-
AGE OR ANY CRACK IS
FOUND DURING THE
DETAILED INSPECTION
OF THE AILERON TRIM
ACTUATOR ATTACH-
MENT LUG
Export Controlled ECCN: 9E991
Copyright © Unpublished
Work - See page 1 for details.
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757-27A0159 RBRevision 1: April 29, 2020
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REQUIREMENTS BULLETIN 757-27A0159
ALERTALERT

### Page 17

Table 2: Detailed Inspection of the Aileron Trim Actuator Attachment Lug
Refer to the listed
procedures in SB
757-27A0159
Original Issue or
later approved re-
visions as an ac-
cepted proce-
dure.
Method of Compli-
ance
ActionCondition
--CONDITION 3.1 (AC-
TION 1): Contact the
Boeing Company for re-
pair instructions and do
the repair.
CONDITION 3.1: ANY
CRACK IS FOUND DUR-
ING THE HFEC INSPEC-
TION OF THE AILERON
TRIM ACTUATOR AT-
TACHMENT LUG Do PART 3:
RESTORATION
--
-FIGURE 3CONDITION 3.1 (AC-
TION 2): Repeat Detailed
Inspection of the Aileron
Trim Actuator attachment
lug for any damage and
any crack. (a)
Do PART 3:
RESTORATION
--CONDITION 3.2: NO
CRACK IS FOUND DUR-
ING THE HFEC INSPEC-
TION OF THE AILERON
TRIM ACTUATOR AT-
TACHMENT LUG
-FIGURE 3Repeat Detailed Inspec-
tion of the Aileron Trim
Actuator attachment lug
for any damage and any
crack. (a)
Do PART 3:
RESTORATION
--CONDITION 4: NO DAM-
AGE AND NO CRACK IS
FOUND DURING THE
DETAILED INSPECTION
OF THE AILERON TRIM
ACTUATOR ATTACH-
MENT LUG
-FIGURE 3Repeat Detailed Inspec-
tion of the Aileron Trim
Actuator attachment lug
for any damage or any
crack. (a)
(a) Damage is defined as: Any surface problems, such as scratches or dings, which have
occurred after the part was manufactured.
(b) If a HFEC inspection of the Aileron Trim Actuator attachment lug for any crack is found to
be required as an action for both CONDITION 1 and CONDITION 3, the HFEC inspection
is only required to be done once before further flight.
Export Controlled ECCN: 9E991
Copyright © Unpublished
Work - See page 1 for details.
Original Issue: March 29, 2019
757-27A0159 RBRevision 1: April 29, 2020
17 of 23
REQUIREMENTS BULLETIN 757-27A0159
ALERTALERT

### Page 18 (OCR)

REQUIREMENTS BULLETIN 757-27A0159
ALERT  ALERT
WL
166.0
INBD
FEEL, CENTERING, AND TRIM MECHANISM
(VIEW LOOKING FORWARD)
2852517
FIGURE 2: MAIN LANDING GEAR WHEEL WELL - AILERONTRIM ACTUATOR BEARING - ROTATION
_ CHECK
(SHEET 1 OF 2)
Original Issue: March 29, 2019
Revision 1 April 29, 2020  Export Controlled ECCN: 9E991  757-27A0159 RB
Copyright © Unpublished
Work - See page 1 for details.  18 of 23

### Page 19

The step numbers shown below agree with the numbers shown in the circle symbols in the figure. The QTY
numbers shown below are the number of parts necessary for this figure.
More DataQtyIdentificationNameTaskStep
(a)1-BEARINGTurn1
(a) Gently turn the Aileron Trim Actuator bearing manually to make sure it turns freely. A bearing that turns
freely is defined as: A bearing that moves without ratchet, gritty, or detent like feeling.
FIGURE 2: MAIN LANDING GEAR WHEEL WELL - AILERON TRIM ACTUATOR BEARING - ROTATION
CHECK
(SHEET 2 OF 2)
Export Controlled ECCN: 9E991
Copyright © Unpublished
Work - See page 1 for details.
Original Issue: March 29, 2019
757-27A0159 RBRevision 1 April 29, 2020
19 of 23
REQUIREMENTS BULLETIN 757-27A0159
ALERTALERT

### Page 20 (OCR)

REQUIREMENTS BULLETIN 757-27A0159
ALERT  ALERT
WL
166.0
INBD
a INSPECTION AREA
FEEL, CENTERING, AND TRIM MECHANISM
(VIEW LOOKING FORWARD)
FIGURE 3: MAIN LANDING GEAR WHEEL WELL - AILERONTRIM ACTUATOR ATTACHMENT LUG -
DETAILED INSPECTION
(SHEET 1 OF 2)
Original Issue: March 29, 2019
Revision 1 April 29, 2020  Export Controlled ECCN: 9E991  757-27A0159 RB
Copyright © Unpublished
Work - See page 1 for details.  20 of 23

### Page 21

The step numbers shown below agree with the numbers shown in the circle symbols in the figure. The QTY
numbers shown below are the number of parts necessary for this figure.
More DataQtyIdentificationNameTaskStep
(a)(b)1251N1258-4BOX SUPPORT ASSYInspect1
(a) Do a Detailed Inspection of all sides of the Aileron Trim Actuator attachment lug for any damage or any
crack.
(b) Damage is defined as: Any surface problems, such as scratches or dings, which have occurred after the
part was manufactured.
FIGURE 3: MAIN LANDING GEAR WHEEL WELL - AILERON TRIM ACTUATOR ATTACHMENT LUG -
DETAILED INSPECTION
(SHEET 2 OF 2)
Export Controlled ECCN: 9E991
Copyright © Unpublished
Work - See page 1 for details.
Original Issue: March 29, 2019
757-27A0159 RBRevision 1 April 29, 2020
21 of 23
REQUIREMENTS BULLETIN 757-27A0159
ALERTALERT

### Page 22 (OCR)

REQUIREMENTS BULLETIN 757-27A0159
ALERT  ALERT
WL
166.0
INBD
INSPECTION AREA
FEEL, CENTERING, AND TRIM MECHANISM
(VIEW LOOKING FORWARD)
FIGURE 4: MAIN LANDING GEAR WHEEL WELL - AILERON TRIM ACTUATOR ATTACHMENT LUG - HIGH
FREQUENCY EDDY CURRENT (HFEC) INSPECTION
(SHEET 1 OF 2)
Original Issue: March 29, 2019
Revision 1 April 29, 2020  Export Controlled ECCN: 9E991  757-27A0159 RB
Copyright © Unpublished
Work - See page 1 for details.  22 of 23

### Page 23

The step numbers shown below agree with the numbers shown in the circle symbols in the figure. The QTY
numbers shown below are the number of parts necessary for this figure.
More DataQtyIdentificationNameTaskStep
(a)1251N1258-4BOX SUPPORT ASSYInspect1
(a) Do a HFEC inspection of all sides of the Aileron Trim Actuator attachment lug for any crack in accordance
with 757 NDT Manual Part 6, 51-00-19.
FIGURE 4: MAIN LANDING GEAR WHEEL WELL - AILERON TRIM ACTUATOR ATTACHMENT LUG - HIGH
FREQUENCY EDDY CURRENT (HFEC) INSPECTION
(SHEET 2 OF 2)
Export Controlled ECCN: 9E991
Copyright © Unpublished
Work - See page 1 for details.
Original Issue: March 29, 2019
757-27A0159 RBRevision 1 April 29, 2020
23 of 23
REQUIREMENTS BULLETIN 757-27A0159
ALERTALERT

---
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