# Boeing Alert Requirements Bulletin 777-27A0125 RB: No revision named

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- Title as filed: 777-27A0125 RB
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### Page 1

Commercial 
Airplanes
777
Requirements Bulletin
ALERT
Number: 777-27A0125 RB
Original Issue: February 03, 2023
ATA System: 2721
SUBJECT: FLIGHT CONTROLS - Rudder Control System - Gust Suppression Sensor Transorb
Module Replacement
EXPORT CONTROLLED - This technology or software is subject to the U.S. Export Administration Regulations
(EAR), (15 C.F.R. Parts 730-774). No authorization from the U.S. Department of Commerce is required for
export, re-export, in-country transfer, or access EXCEPT to country group E:1 or E:2 countries/persons per
Supp.1 to Part 740 of the EAR.
9E991ECCN:
Copyright © 2023 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Unpublished Work.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.
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Export Controlled ECCN: 9E991
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REQUIREMENTS BULLETIN 777-27A0125
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Table of Contents
1. EFFECTIVITY . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
A. Airplanes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
B. Spares Affected . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
2. CONCURRENT REQUIREMENTS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
3. COMPLIANCE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
4. APPROVAL . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
5. ACCOMPLISHMENT INSTRUCTIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
A. General Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
B. Work Instructions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
FIGURE 1: UPPER GUST SUPPRESSION SENSOR TRANSORB MODULE REMOVAL . . . . . . . 16
FIGURE 2: UPPER GUST SUPPRESSION SENSOR TRANSORB MODULE INSTALLATION . . . . 19
FIGURE 3: LOWER GUST SUPPRESSION SENSOR TRANSORB MODULE REMOVAL . . . . . . . 22
FIGURE 4: LOWER GUST SUPPRESSION SENSOR TRANSORB MODULE INSTALLATION . . . . 25
FIGURE 5: PART MARKING . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28
APPENDIX A: ACCEPTANCE TEST PROCEDURE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29
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Export Controlled ECCN: 9E991
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Commercial 
Airplanes
777
Requirements Bulletin
ALERT
Number: 777-27A0125 RB
Original Issue: February 03, 2023
ATA System: 2721
SUBJECT: FLIGHT CONTROLS - Rudder Control System - Gust Suppression Sensor Transorb
Module Replacement
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 777-200, 777-200LR, 777-300, 777-300ER, 777F Airplane(s), line
number(s) 1-1566, 1568-1573, 1575-1580, 1582-1586, 1588-1604, 1606-1610, 1612-1614,
1616-1619, 1621-1623, 1625-1628, 1630-1632, 1634-1637, 1639-1641, 1643-1646, 1648-1650,
1652-1655, 1657-1658, 1660-1667, 1669, 1671, 1673, 1675-1676, 1678-1679, 1681, 1683-1684,
1686-1687, 1689-1715, 1717-1722, 1724-1726 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
777-200, 777-200LR, 777-300, 777-300ER and 777F airplanes.- 1
Airplane Models:
777-200, 777-200LR, 777-300, 777-300ER, 777F
GroupVariable Number
1WA001 - WA017
1WA076 - WA080
GroupVariable Number
1WA086 - WA093
1WA101 - WA104
GroupVariable Number
1WA116 - WA119
1WA131 - WA137
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GroupVariable Number
1WA171 - WA175
1WA196 - WA198
1WA206 - WA212
1WA221 - WA223
1WA231 - WA232
1WA241 - WA250
1WA261 - WA266
1WA281 - WA283
1WA301 - WA304
1WB001 - WB021
1WB031 - WB046
1WB051 - WB088
1WB101 - WB106
1WB121 - WB125
1WB131 - WB148
1WB151 - WB155
1WB161 - WB177
1WB181 - WB194
1WB201 - WB215
1WB231 - WB247
1WB271 - WB273
1WB276 - WB286
1WB291 - WB302
1WB306 - WB307
1WB311 - WB337
1WB341 - WB342
1WB366 - WB368
1WB371 - WB388
1WB406
1WB411 - WB413
1WB416 - WB439
1WB446 - WB453
1WB476
GroupVariable Number
1WB481 - WB484
1WB501 - WB512
1WB531 - WB537
1WB551 - WB554
1WB591 - WB597
1WB601 - WB606
1WB611 - WB622
1WB631 - WB638
1WB646 - WB649
1WC051 - WC073
1WC101 - WC104
1WC111 - WC120
1WC221 - WC224
1WC241 - WC243
1WC281 - WC290
1WC301 - WC308
1WC361 - WC364
1WC371 - WC374
1WC381 - WC395
1WC441
1WC446 - WC449
1WC456 - WC459
1WC486 - WC493
1WC506 - WC508
1WC521 - WC522
1WC531 - WC536
1WC546 - WC548
1WC556
1WC566 - WC567
1WC571 - WC574
1WC581
1WC586 - WC587
1WC591 - WC595
GroupVariable Number
1WD001 - WD002
1WD011 - WD018
1WD031 - WD036
1WD046 - WD055
1WD066 - WD075
1WD081 - WD089
1WD091
1WD096
1WD101 - WD106
1WD111 - WD112
1WD116 - WD117
1WD121 - WD123
1WD156
1WD501 - WD513
1WD521 - WD541
1WD546 - WD554
1WD561 - WD573
1WD581 - WD599
1WD606 - WD609
1WD621 - WD632
1WD651 - WD665
1WD671 - WD677
1WD691 - WD709
1WD741 - WD752
1WD761 - WD771
1WD786 - WD788
1WD796 - WD837
1WD846 - WD867
1WD871 - WD918
1WD921 - WD957
1WD966 - WD970
1WD981 - WD982
1WD986 - WD987
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GroupVariable Number
1WD991 - WD996
1WE001 - WE007
1WE011 - WE012
1WE021 - WE026
1WE031 - WE040
1WE051 - WE057
1WE071 - WE078
1WE081 - WE084
1WE091 - WE095
1WE126 - WE178
1WE186 - WE219
1WE226 - WE231
1WE236 - WE253
1WE261 - WE267
1WE271 - WE278
1WE291 - WE298
1WE301 - WE320
1WE331 - WE356
1WE366 - WE368
1WE376 - WE377
1WE381
1WE386 - WE387
1WE391 - WE392
1WE396 - WE411
1WE416 - WE420
1WE426 - WE431
1WE436 - WE446
1WE451 - WE484
1WE486 - WE493
1WE495 - WE499
1WE501 - WE504
GroupVariable Number
1WE511 - WE516
1WE526 - WE528
1WE536 - WE549
1WE556 - WE573
1WE576 - WE587
1WE591
1WE601 - WE605
1WE626 - WE627
1WE631
1WE641 - WE642
1WE646 - WE647
1WE651 - WE661
1WE666 - WE677
1WE681 - WE689
1WE701 - WE705
1WE711 - WE712
1WE731 - WE732
1WE736 - WE740
1WE746 - WE772
1WE776 - WE786
1WE791 - WE792
1WE796 - WE798
1WE801 - WE806
1WE811 - WE812
1WE826 - WE828
1WE831 - WE835
1WE851 - WE853
1WE856 - WE857
1WE861 - WE863
1WE866 - WE868
1WE871
GroupVariable Number
1WF001 - WF004
1WF016 - WF029
1WF031 - WF043
1WF046 - WF077
1WF081 - WF088
1WF096 - WF101
1WF106 - WF109
1WF111 - WF124
1WF131 - WF144
1WF146 - WF147
1WF151 - WF152
1WF156 - WF173
1WF176 - WF184
1WF191
1WF201
1WF206 - WF217
1WF221 - WF228
1WF231 - WF248
1WF256 - WF258
1WF261 - WF262
1WF266 - WF288
1WF296
1WF301 - WF306
1WF311 - WF314
1WF321
1WF326 - WF328
1WF336 - WF342
1WF366 - WF367
1WF371 - WF372
--
--
B. Spares Affected
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Examine your spares supply for the parts or components identified below. If any parts or components
are found, refer to APPENDIX A for the recommended action.
NamePart Number
TRANSORB CONNECTOR ADAPTER ASSEMBLYCLPT-12SP-06
TRANSORB CONNECTOR ADAPTER ASSEMBLYCLPT-12SP-07
TRANSORB CONNECTOR ADAPTER ASSEMBLYCLPT-12SP-67
2. CONCURRENT REQUIREMENTS
None.
3. COMPLIANCE
Federal Aviation Administration (FAA) Airworthiness Directive AD 2022-15-06 is related to this bulletin. The
effective date of AD 2022-15-06 is August 18, 2022.
The Federal Aviation Administration (FAA) will possibly release an Airworthiness Directive related to
Requirements Bulletin 777-27A0125 RB. The Airworthiness Directive will make the compliance tasks and
times given in Requirements Bulletin 777-27A0125 RB mandatory.
Accomplish the required action(s), based on the applicable condition(s) in Table 1, in accordance with
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.
Export Controlled ECCN: 9E991
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Table1: Gust Suppression Sensor Transorb Module - Replacement.
Repeat Interval
(Not to Exceed)
Boeing Recommended
Compliance Time
ActionCondition
-Within 24 months after
the Original Issue date of
Requirements Bulletin
777-27A0125 RB or
within 24 months after
the date of issuance of
the original standard cer-
tificate of airworthiness
or the original export cer-
tificate of airworthi-
ness,whichever occurs
later.
OPTION 1: Do Accep-
tance Test Procedure
(ATP) of the upper and
lower Gust Suppression
Sensor Transorb (GSST)
modules to measure
overall length and electri-
cal resistance.
All Airplanes
-OPTION 2: Replace up-
per and lower GSST with
new or serviceable
GSST(a)
-CONDITION 1 OPTION
1 (ACTION 1): Part mark
affected GSST.
CONDITION 1: ANY GSST
MODULE WITH AN
OVERALL LENGTH
EQUAL TO OR LESS
THAN 2.490 INCHES AND
ELECTRICAL RESIS-
TANCE IS LESS THAN OR
EQUAL TO 0.30 MIL-
LIOHMS AS A RESULT
OF OPTION 1 ATP
-CONDITION 1 OPTION
1 (ACTION 2): Install af-
fected Part marked GSST
-CONDITION 1 OPTION
2: Replace affected
GSST with new or service-
able GSST(a)
-Replace affected GSST
with new or serviceable
GSST(a)
CONDITION 2: ANY GSST
MODULE WITH AN
OVERALL LENGTH MORE
THAN 2.490 INCHES AND
ANY MEASURED ELEC-
TRICAL RESISTANCE
VALUE AS A RESULT OF
OPTION 1 ATP
-Replace affected GSST
with new or serviceable
GSST(a)
CONDITION 3: ANY GSST
MODULE WITH AN
OVERALL LENGTH
EQUAL TO OR LESS
THAN 2.490 INCHES AND
ELECTRICAL RESIS-
TANCE IS MORE THAN
0.30 MILLIOHMS AS A
RESULT OF OPTION 1
ATP
(a) A serviceable GSST module is defined as GSST module that has an overall length of less than
or equal to 2.490 inches and an electrical resistance of less than or equal to 0.30 milliohms and
that has been part marked with part number CLPT-12SP-67-3, CLPT-12SP-06-3, or CLPT-12SP-
07-3.
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4. APPROVAL
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
Union Aviation Safety Agency (EASA)/Joint Aviation Authorities (JAA) approved for all EASA/JAA approved
airplanes listed in this 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 Seattle ACO Branch approves accomplishment of the changes defined
in this bulletin as an alternative method of compliance to accomplishing the actions required by paragraph
(g) of AD 2022-15-06. Note that airplanes that have not been modified by this bulletin prior to the compliance
times of paragraphs (g)(1) and (g)(2) (whichever occurs later) of AD 2022-15-06 must accomplish the actions
required by of paragraph (g) of the AD within the AD compliance times. All provisions of AD 2022-15-06
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 777 Structural Repair Manual,
Chapter 51.
— Values for airframe maintenance tasks are included in Chapter 20 of 777
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 777
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. 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.
7. 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.
8. Use the approved fastener, process and material substitutions in accordance with
SRM Chapter 51.
9. 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.
10. The instructions in 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.
11. Refer to the SWPM 20-10-11 and SWPM 20-10-12 for the wire installation procedures,
and SWPM 20-10-19 for the wire separation requirements, as accepted procedures.
12. The necessary conditions for selection of clamp type and size are included in SWPM
20-10-12. If any wire bundle support clamp specified in this service bulletin does not
make a correct fit on the wire bundle, refer to SWPM 20-10-12 as an accepted
procedure to select a clamp that fits correctly.
B. WORK INSTRUCTIONS
Actions Required For Compliance
1. Requirements
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Table1: Gust Suppression Sensor Transorb Module - Replacement.
Refer to the listed
procedures in SB
777-27A0125 RB
Original Issue or
later approved re-
visions as an ac-
cepted proce-
dure.
Method of ComplianceActionCondition
Do PART 1: OPEN
ACCESS
-OPTION 1: Do Accep-
tance Test Procedure
(ATP) of the upper and
lower Gust Suppression
Sensor Transorb (GSST)
modules to measure
overall length and electri-
cal resistance
All Airplanes
-FIGURE 1, FIGURE 3,
and APPENDIX A
Do PART 1: OPEN
ACCESS
-OPTION 2: Replace up-
per and lower GSST with
new or serviceable
GSST(a) -FIGURE 1, FIGURE 2,FIGURE 3, and FIGURE
4
Do PART 2: GUST
SUPPRESSION
SENSOR TRAN-
SORB REPLACE-
MENT TEST
-
Do PART 3:
CLOSE ACCESS
-
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Table1: Gust Suppression Sensor Transorb Module - Replacement.
Refer to the listed
procedures in SB
777-27A0125 RB
Original Issue or
later approved re-
visions as an ac-
cepted proce-
dure.
Method of ComplianceActionCondition
-FIGURE 5CONDITION 1 OPTION
1 (ACTION 1): Part mark
affected GSST
CONDITION 1: ANY GSST
MODULE WITH AN
OVERALL LENGTH
EQUAL TO OR LESS
THAN 2.490 INCHES AND
ELECTRICAL RESIS-
TANCE IS LESS THAN OR
EQUAL TO 0.30 MIL-
LIOHMS AS A RESULT
OF OPTION 1 ATP
-FIGURE 2 and FIGURE
4
CONDITION 1 OPTION
1 (ACTION 2): Install af-
fected Part marked GSST Do PART 2: GUST
SUPPRESSION
SENSOR TRAN-
SORB REPLACE-
MENT TEST
-
Do PART 3:
CLOSE ACCESS
-
-FIGURE 2 and FIGURE
4
CONDITION 1 OPTION
2: Replace affected
GSST with new or service-
able GSST (a) Do PART 2: GUSTSUPPRESSION
SENSOR TRAN-
SORB REPLACE-
MENT TEST
-
Do PART 3:
CLOSE ACCESS
-
-FIGURE 2 and FIGURE
4
Replace affected GSST
with new or serviceable
GSST(a)
CONDITION 2: ANY GSST
MODULE WITH AN
OVERALL LENGTH MORE
THAN 2.490 INCHES AND
ANY MEASURED ELEC-
TRICAL RESISTANCE
VALUE AS A RESULT OF
OPTION 1 ATP
Do PART 2: GUST
SUPPRESSION
SENSOR TRAN-
SORB REPLACE-
MENT TEST
-
Do PART 3:
CLOSE ACCESS
-
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Original Issue: February 03, 2023
777-27A0125 RB
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REQUIREMENTS BULLETIN 777-27A0125
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ENCLOSURE C 
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### Page 15

Table1: Gust Suppression Sensor Transorb Module - Replacement.
Refer to the listed
procedures in SB
777-27A0125 RB
Original Issue or
later approved re-
visions as an ac-
cepted proce-
dure.
Method of ComplianceActionCondition
-FIGURE 2 and FIGURE
4
Replace affected GSST
with new or serviceable
GSST(a)
CONDITION 3: ANY GSST
MODULE WITH AN
OVERALL LENGTH
EQUAL TO OR LESS
THAN 2.490 INCHES AND
ELECTRICAL RESIS-
TANCE IS MORE THAN
0.30 MILLIOHMS AS A
RESULT OF OPTION 1
ATP
Do PART 2: GUST
SUPPRESSION
SENSOR TRAN-
SORB REPLACE-
MENT TEST
-
Do PART 3:
CLOSE ACCESS
-
(a) A serviceable GSST module is defined as GSST module that has an overall length of less than
or equal to 2.490 inches and an electrical resistance of less than or equal to 0.30 milliohms and
that has been part marked with part number CLPT-12SP-67-3, CLPT-12SP-06-3, or CLPT-12SP-
07-3.
Export Controlled ECCN: 9E991
Copyright © Unpublished Work - See page 1 for details.
Original Issue: February 03, 2023
777-27A0125 RB
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REQUIREMENTS BULLETIN 777-27A0125
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ENCLOSURE C 
DLD4-23-00128
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### Page 16 (OCR)

ENCLOSURE C
DLD4-23-00128
REQUIREMENTS BULLETIN 777-27A0125
ALERT  ALERT
STA
2129
POSITION 6
OR B  CONNECTORS NOT SHOWN FOR CLARITY  (VIEW LOOKING AFT)
A-A
1 CONNECTOR  D02006P
DISCONNECT  STA
PANEL AP2122  2129  TYPICAL
FIGURE 1: UPPER GUST SUPPRESSION SENSOR TRANSORB MODULE REMOVAL
(SHEET 1 OF 3)
Original Issue: February 03, 2023
777-27A0125 RB
Export Controlled ECCN: 9E991
Copyright © Unpublished Work - See page 1 for details.  16 of 30
Boeing Proprietary

### Page 17 (OCR)

ENCLOSURE C
DLD4-23-00128
REQUIREMENTS BULLETIN 777-27A0125
ALERT  ALERT
CONNECTOR 1  D02098P  STA  VENO  AP2122A  DISCONNECT PANEL
2129
TYPICAL
B
TRANSORB
CONNECTOR
ADAPTER
ASSEMBLY
TYPICAL
3012471
FIGURE 1: UPPER GUST SUPPRESSION SENSOR TRANSORB MODULE REMOVAL
(SHEET 2 OF 3)
Original Issue: February 03, 2023
777-27A0125 RB
Export Controlled ECCN: 9E991
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Boeing Proprietary

### Page 18

The step numbers shown below agree with the numbers shown in the circle symbols in the figure. The QTY
numbers shown below are the number of parts necessary for this figure.
More DataQtyIdentificationNameTaskStep
Refer to SOPM 20-
10-23 as an accept-
ed procedure.
--LOCKWIRERemove1
If connector
D02006P is used.
1D02006PCONNECTORDisconnect
If connector D02098
is used.
1D02098PCONNECTORDisconnect
(a) 1CLPT-12SP-07 OR
CLPT-12SP-67
TRANSORB CONNEC-
TOR ASSEMBLY
Remove / Keep2
(a) If the option to test the transorb connector adapter assembly per the Acceptance Test Procedure (ATP)
is selected, keep the existing transorb connector adapter assembly.
FIGURE 1: UPPER GUST SUPPRESSION SENSOR TRANSORB MODULE REMOVAL
(SHEET 3 OF 3)
Export Controlled ECCN: 9E991
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Original Issue: February 03, 2023
777-27A0125 RB
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REQUIREMENTS BULLETIN 777-27A0125
ALERTALERT
ENCLOSURE C 
DLD4-23-00128
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### Page 19 (OCR)

ENCLOSURE C
DLD4-23-00128
REQUIREMENTS BULLETIN 777-27A0125
ALERT  ALERT
STA
2129
POSITION 6•
CONNECTORS NOT SHOWN FOR CLARITY
OR  (VIEW LOOKING AFT
A-A
DISCONNECT  1 002006CTOR
PANEL AP2122  STA
2129  TYPICAL  3011310
FIGURE 2: UPPER GUST SUPPRESSION SENSOR TRANSORB MODULE INSTALLATION
(SHEET 1 OF 3)
Original Issue: February 03, 2023
Export Controlled ECCN: 9E991  777-27A0125 RB
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Boeing Proprietary

### Page 20 (OCR)

ENCLOSURE C
DLD4-23-00128
REQUIREMENTS BULLETIN 777-27A0125
ALERT  ALERT
•
DISCONNECT  2 CONNECTOR
STA  PWD  PANEL AP2122A  D02099P
2129
ALTERNATIVE INSTALLATION
(TYPICAL)
DISCONNECT
PANEL
TRANSORB
RECEPTACLE  ADAPTER  ASSEMBLY
DISCONNECT
*PANEL
RECEPTACLE
GUST
SUPPRESSION
BUNDLE
YPICAL
3012488
FIGURE 2: UPPER GUST SUPPRESSION SENSOR TRANSORB MODULE INSTALLATION
(SHEET 2 OF 3)
Original Issue: February 03, 2023
777-27A0125 RB
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Boeing Proprietary

### 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
If transorb connector
adapter assembly
P/N CLPT-12SP-07
was removed. (b)
1CLPT-12SP-07-1
(CLPT-12SP-07-3 op-
tional)
TRANSORB CONNEC-
TOR ADAPTER AS-
SEMBLY
Install (New)1
If transorb connector
adapter assembly
P/N CLPT-12SP-67
was removed.(b)
1CLPT-12SP-67-1
(CLPT-12SP-67-3 op-
tional)
TRANSORB CONNEC-
TOR ADAPTER AS-
SEMBLY
Install (New)
If connector
D02006P is used,
connect connector
D02006P to the
transorb connector
adapter assembly.
1D02006PCONNECTORConnect2
If connector
D02098P is used,
connect connector
D02098P to the
transorb connector
adapter assembly.
1D02098PCONNECTORConnect
If connector
D02099P is used,
and was Cap and
Stowed, connect
connector D02099P
to D02099J.
1D02099PCONNECTORConnect
(a) -AS3510-0118LLOCKWIREInstall (New)
(c) --RESISTANCEMeasure3
(a) Refer to SOPM 20-50-02 as an accepted procedure.
(b) As an alternative, a kept serviceable transorb connector adapter assembly can be installed.
(c) Make sure the plug to receptacle electrical resistance is less than 2 milliohms. Refer to SWPM 20-60-06
as an accepted procedure.
FIGURE 2: UPPER GUST SUPPRESSION SENSOR TRANSORB MODULE INSTALLATION
(SHEET 3 OF 3)
Export Controlled ECCN: 9E991
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REQUIREMENTS BULLETIN 777-27A0125
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ENCLOSURE C 
DLD4-23-00128
Boeing Proprietary

### Page 22 (OCR)

ENCLOSURE C
DLD4-23-00128
REQUIREMENTS BULLETIN 777-27A0125
ALERT  ALERT
POSITION 2
STA
2129
OR  CONNECTORS NOT SHOWN FOR CLARITY
(VIEW LOOKING AFT)
A-A
DISCONNECT
PANEL AP2121  STA
2129
TYPICAL
3011301
FIGURE 3: LOWER GUST SUPPRESSION SENSOR TRANSORB MODULE REMOVAL
(SHEET 1 OF 3)
Original Issue: February 03, 2023
777-27A0125 RB
Export Controlled ECCN: 9E991
Copyright © Unpublished Work - See page 1 for details.  22 of 30
Boeing Proprietary

### Page 23 (OCR)

ENCLOSURE C
DLD4-23-00128
REQUIREMENTS BULLETIN 777-27A0125
ALERT  ALERT
2129  STA  PANEL AP2121A  DISCONNECT
TYPICAL
POSITION 3
CONNECTORS NOT SHOWN FOR CLARITY
(VIEW LOOKING AFT)  3014311
B-B
FIGURE 3: LOWER GUST SUPPRESSION SENSOR TRANSORB MODULE REMOVAL
(SHEET 2 OF 3)
Original Issue: February 03, 2023
Export Controlled ECCN: 9E991  777-27A0125 RB
Copyright © Unpublished Work - See page 1 for details.  23 of 30
Boeing Proprietary

### Page 24

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
- --LOCKWIRERemove1
If connector
D02005P is used.
1D02005PCONNECTORDisconnect
Disconnect at Panel
AP2121 or
AP2121A, as applica-
ble. (a)
1CLPT-12SP-06 OR
CLPT-12SP-67
TRANSORB CONNEC-
TOR ASSEMBLY
Remove / Keep2
(a) If the option to test the transorb connector adapter assembly in accordance with the Acceptance Test
Procedure (ATP) is selected, keep the existing transorb connector adapter assembly.
FIGURE 3: LOWER GUST SUPPRESSION SENSOR TRANSORB MODULE REMOVAL
(SHEET 3 OF 3)
Export Controlled ECCN: 9E991
Copyright © Unpublished Work - See page 1 for details.
Original Issue: February 03, 2023
777-27A0125 RB
24 of 30
REQUIREMENTS BULLETIN 777-27A0125
ALERTALERT
ENCLOSURE C 
DLD4-23-00128
Boeing Proprietary

### Page 25 (OCR)

ENCLOSURE C
DLD4-23-00128
REQUIREMENTS BULLETIN 777-27A0125
ALERT  ALERT
POSITION 2
STA
2129
CONNECTORS NOT SHOWN FOR CLARITY
OR  (VIEW LOOKING AFT)
A-A
DISCONNECT
PANEL AP2121  STA
2129
TYPICAL
3011311
FIGURE 4: LOWER GUST SUPPRESSION SENSOR TRANSORB MODULE INSTALLATION
(SHEET 1 OF 3)
Original Issue: February 03, 2023
777-27A0125 RB
Export Controlled ECCN: 9E991
Copyright © Unpublished Work - See page 1 for details.  25 of 30
Boeing Proprietary

### Page 26 (OCR)

ENCLOSURE C
DLD4-23-00128
REQUIREMENTS BULLETIN 777-27A0125
ALERT  ALERT
2129  STA  PANEL AP2121A  DISCONNECT
TYPICAL
POSITION 3
CONNECTORS NOT SHOWN FOR CLARITY  (VIEW LOOKING AFT)  3012498
B-B
FIGURE 4: LOWER GUST SUPPRESSION SENSOR TRANSORB MODULE INSTALLATION
(SHEET 2 OF 3)
Original Issue: February 03, 2023
777-27A0125 RB
Export Controlled ECCN: 9E991
Copyright © Unpublished Work - See page 1 for details.  26 of 30
Boeing Proprietary

### Page 27

The step numbers shown below agree with the numbers shown in the circle symbols in the figure. The QTY
numbers shown below are the number of parts necessary for this figure.
More DataQtyIdentificationNameTaskStep
If transorb connector
adapter assembly
P/N CLPT-12SP-06
was removed.(b)
1CLPT-12SP-06-1
(CLPT-12SP-06-3 op-
tional)
TRANSORB CONNEC-
TOR ADAPTER AS-
SEMBLY
Install (New)1
If transorb connector
adapter assembly
P/N CLPT-12SP-67
was removed.(b)
1CLPT-12SP-67-1
(CLPT-12SP-67-3 op-
tional)
TRANSORB CONNEC-
TOR ADAPTER AS-
SEMBLY
Install (New)
1D2005PCONNECTORConnect2
(a) -AS3510-0118LLOCKWIREInstall (New)
(c) --RESISTANCEMeasure3
(a) Refer to SOPM 20-50-02 as an accepted procedure.
(b) As an alternative, a kept serviceable transorb connector adapter assembly can be installed.
(c) Make sure the plug to receptacle resistance is less than 2 milliohms. Refer to SWPM 20-60-06 as an ac-
cepted procedure.
FIGURE 4: LOWER GUST SUPPRESSION SENSOR TRANSORB MODULE INSTALLATION
(SHEET 3 OF 3)
Export Controlled ECCN: 9E991
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Original Issue: February 03, 2023
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REQUIREMENTS BULLETIN 777-27A0125
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ENCLOSURE C 
DLD4-23-00128
Boeing Proprietary

### Page 28

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
-M23053/5HEAT SHRINKApply1
(a) 1-TRANSORB CONNEC-
TOR ADAPTER AS-
SEMBLY
Identify2
(a) Part mark as CLPT-12SP-06-3, if existing part number was CLPT-12SP-06, in accordance with SWPM
20-10-11.
Part mark as CLPT-12SP-07-3, if existing part number was CLPT-12SP-07, in accordance with SWPM
20-10-11.
Part mark as CLPT-12SP-67-3, if existing part number was CLPT-12SP-67, in accordance with SWPM
20-10-11
FIGURE 5: PART MARKING
(SHEET 1 OF 1)
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ENCLOSURE C 
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### Page 29

GUST SUPPRESSION SENSOR TRANSORB ACCEPTANCE TEST PROCEDURE (ATP):
The Transorb must be tested to make sure it meets type design before it is installed on an airplane. The purposes
of the ATP test are:
1. Detection of improperly engaged Anti-Rotation teeth.
2. Electrical Resistance check to make sure transorb meets type design electrical resistance requirements.
Test Procedure:
1. Measure and record the overall length of the transorb (See VIEW 1).
2. Use a bond meter (refer to SWPM 20-20-00 as an accepted procedure) to measure the end to end
resistance of the transorb (See VIEW 2).
NOTE: Make sure there is no side-load on the transorb during the resistance check.
APPENDIX A:  ACCEPTANCE TEST PROCEDURE
(SHEET 1 OF 2)
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ENCLOSURE C 
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### Page 30

APPENDIX A:  ACCEPTANCE TEST PROCEDURE
(SHEET 2 OF 2)
Export Controlled ECCN: 9E991
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REQUIREMENTS BULLETIN 777-27A0125
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ENCLOSURE C 
DLD4-23-00128
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