# Boeing Alert Service Bulletin 727-57A0135: Revision 4

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- Document: [Boeing Alert Service Bulletin 727-57A0135](https://openairdocs.org/service-documents/boeing/727-57a0135.md)
- Title as filed: U.S. DOT/FAA - SB-727-57A0135-04
- Pages: 37
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## Text

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### Page 1

Commercial 
Airplanes
727
Service Bulletin
ALERT
Number: 727-57A0135
Original Issue: February 07, 1975
Revision 4: September 26, 2012
ATA System: 5742
SUBJECT: ATTACH FITTINGS Flight Control - Foreflap Carriage Attachment Inspection And
Adjustment
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:
BOEING PROPRIETARY, CONFIDENTIAL AND/OR TRADE SECRET
Copyright © 1989 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Unpublished Work.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, KDC-10, MD-10, MD-11, MD-80, MD-88, MD-90, P-8A, 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. BOEING is a trademark of Boeing Management
Company.
Original Issue: February 07, 1975
727-57A0135Revision 4: September 26, 2012
1 of 37
4.0

### Page 2

Export Controlled ECCN: 9E991 - BOEING
PROPRIETARY - Copyright © Unpublished
Work - See page 1 for details.
Original Issue: February 07, 1975
727-57A0135Revision 4: September 26, 2012
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BOEING SERVICE BULLETIN 727-57A0135
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 6
C. Reason ................................................ 1 6
D. Description .............................................. 1 8
E. Compliance .............................................. 1 8
F. Approval ............................................... 2 0
G. Manpower .............................................. 2 0
H. Weight and Balance Changes .................................... 2 1
I. Electrical Load Data ......................................... 2 1
J. References .............................................. 2 1
1. Existing Data: ......................................... 2 1
2. Data Supplied with this Service Bulletin: ........................... 2 2
3. Installation Drawings Used in the Preparation of this Service Bulletin: ........... 2 2
K. Publications Affected ........................................ 2 2
L. Interchangeability and Intermixability of Parts ........................... 2 2
M. Software Accomplishment Summary ................................ 2 2
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 4
3. Parts Modified and Reidentified ................................ 2 4
4. Parts Removed and Not Replaced .............................. 2 4
D. Parts Necessary to Change Spares ................................. 2 4
E. Special Tooling - Price and Availability ............................... 2 5
F. Special Tooling Necessary to do this Service Bulletin ....................... 2 5
3. ACCOMPLISHMENT INSTRUCTIONS .................................. 2 7
A. GENERAL INFORMATION ..................................... 2 7
B. WORK INSTRUCTIONS ....................................... 2 8
FIGURE 1: INSPECTION .......................................... 3 0
FIGURE 2: CHECK FOR CLEARANCE / INTERFERENCE ....................... 3 2
FIGURE 3: REWORK OF LUG ASSEMBLY ................................ 3 4
FIGURE 4: CARRIAGE FITTING INSTALLATION FOR OUTBOARD FORE FLAP WBL 348 - DEVIATION
FROM OVERHAUL MANUAL ................................. 3 7
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BOEING SERVICE BULLETIN 727-57A0135
ALERTALERT

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Export Controlled ECCN: 9E991 - BOEING
PROPRIETARY - Copyright © Unpublished
Work - See page 1 for details.
Original Issue: February 07, 1975
727-57A0135Revision 4: September 26, 2012
4 of 37
BOEING SERVICE BULLETIN 727-57A0135
ALERTALERT
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Commercial 
Airplanes
727
Service Bulletin
ALERT
Revision Transmittal SheetNumber: 727-57A0135Original Issue: February 07, 1975
Revision 4: September 26, 2012
ATA System: 5742
SUBJECT: ATTACH FITTINGS Flight Control - Foreflap Carriage Attachment Inspection And
Adjustment
This revision includes all pages of the service bulletin.
COMPLIANCE INFORMATION RELATED TO THIS REVISION
More work is necessary on the airplanes changed in accordance with Revision 3 of this service bulletin. For the
outboard foreflap, replace the production carriage attach fittings with the new improved carriage attach fittings
at the time given in Paragraph 1.E., Compliance. Continue to inspect the carriage attach fittings at the interval
given in Paragraph 1.E., Compliance. Do general visual inspections and functionality check of the outboard
foreflap installation for damage and incorrect operation at the interval given in Paragraph 1.E., Compliance.
Federal Aviation Administration (FAA) Airworthiness Directive AD 2005-14-07 is related to this service bulletin.
REASON FOR REVISION
This revision is sent to increase the frequency of the repeat High Frequency Eddy Current (HFEC) inspection
of production outboard foreflap carriage attach fittings, make compulsory the installation of the improved outboard
foreflap carriage attach fittings, make incorporation of the concurrent service bulletins compulsory, add a general
visual inspection and functionality check of the outboard foreflap and to require repeat inspections of the improved
outboard foreflap carriage attach fittings.
Terminology has been changed in the Work Instructions to agree with the terminology defined in Paragraph
3.A., General Information - Notes.
These sections are changed:
1. Summary Background - Reference to a new Boeing Service Related Problem (SRP) and new service
history is added. A Summary Evaluation table is added.
2. The Summary Action is updated.
3. Summary Compliance - Reference to FAA AD 2005-14-07 is added.
4. Paragraph 1.C., Reason - Reference to a new Boeing SRP is added.
5. Paragraph 1.A.1., Airplanes - A Group Configuration Table is added.
Export Controlled ECCN: 9E991 - BOEING
PROPRIETARY - Copyright © Unpublished
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Original Issue: February 07, 1975
727-57A0135Revision 4: September 26, 2012
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6. Paragraph 1.C., Reason - Reference to a new Boeing Service Related Problem (SRP) and new service
history is added. A Summary Evaluation table is added.
7. Paragraph 1.D., Description - Affected maintenance zones are added.
8. Paragraph 1.E., Compliance - Reference to FAA AD 2005-14-07 is added and the compliance information
is updated.
9. Paragraph 1.F., Approval - The approval statement is updated.
10. Paragraph 1.G., Manpower - Manpower information for general visual inspection and functionality
check is added.
11. Paragraph 1.J.1., Existing Data - References to FAA AD 2005-14-07, a new SRP and Service Bulletin
Index are added.
12. Paragraph 1.K., Publications Affected - A Damage Tolerance Inspection (DTI) statement is added.
13. Paragraph 1.M., Software Accomplishment Summary - Section is added.
14. Paragraph 3.A., Accomplishment Instructions - General Note 1 regarding the sequencing of steps is
deleted. A caution and 8 general notes are added.
15. Paragraph 3.B., Work Instructions - Instructions to do a general visual inspection and functionality
check are added.
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
February 07, 1975Original Issue:
August 29, 1975Revision 1:
October 29, 1998Revision 2:
June 27, 2002Revision 3:
September 26, 2012Revision 4:
Export Controlled ECCN: 9E991 - BOEING
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Original Issue: February 07, 1975
727-57A0135Revision 4: September 26, 2012
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BOEING SERVICE BULLETIN 727-57A0135
ALERTALERT

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Commercial 
Airplanes
727
Service Bulletin
ALERT
SummaryNumber: 727-57A0135Original Issue: February 07, 1975
Revision 4: September 26, 2012
ATA System: 5742
SUBJECT: ATTACH FITTINGS Flight Control - Foreflap Carriage Attachment Inspection And
Adjustment
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
Refer to Paragraph 1.B., Concurrent Requirements.
BACKGROUND
This service bulletin gives instructions to inspect the carriage attach fitting of the inboard and outboard foreflaps
for any crack or damage. Fleet service information and analysis show that repeat inspections or replacement
of the carriage attach fitting decrease the risk of partial or complete foreflap loss caused by fatigue. Inspection
and adjustment, if necessary, of the gap between the foreflap carriage attach fitting and the carriage lug on the
inboard and outboard foreflap assemblies will decrease the possibility of fatigue failure of the carriage attach
fitting from excessive clamp-up. The fatigue life of the new replacement fitting increased with the design of
thicker flanges, and a material change to Corrosion Resistant Steel. If the work in this service bulletin is not
done, breakage of the carriage attach fitting could result in the loss of the foreflap and damage to adjacent
structures which could lead to loss of controllability of the airplane during take-off and landing.
Sixteen operators sent reports of twenty-eight damaged or failed outboard Foreflaps with the carriage attach
fitting of the Foreflap Sequencing Carriage cracked or failed. Recent Boeing examination of a failed fitting
indicates fatigue breakage of the fitting is possible as a result of high fit-up stress combined with airloads.
Revision 3 changes this service bulletin to Alert status. It also provides specific inspection intervals for the
carriage attach fitting.
Since the release of Revision 3, one operator has reported that during a scheduled inspection per Federal
Aviation Administration (FAA) Airworthiness Directive AD 2005-14-07 , both inboard and outboard Foreflap
Carriage Fittings were found broken. The event occurred at 47,125 Flight Cycles. Metallurgical analysis determined
that the cause of the broken fittings is a suspected static overload condition.
Boeing Service Related Problem (SRP) 727-SRP-57-0128 and 727-SRP-57-0243  are related to this service
bulletin.
Export Controlled ECCN: 9E991 - BOEING
PROPRIETARY - Copyright © Unpublished
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Original Issue: February 07, 1975
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This table is provided to operators for planning purposes only. Refer to the applicable sections for more
information.
ReferenceAffectedPlanning Data
Paragraph 1.A.2., Spares AffectedYesSpares Affected
Paragraph 1.E., ComplianceYesAD Related
Paragraph 1.H., Weight and Balance ChangesNoWeight and Balance Change
Paragraph 1.I., Electrical Load DataNoElectrical Load Changed
Paragraph 1.K., Publications AffectedYesPublications Affected
Paragraph 1.K., Publications AffectedYesAirplane Flight Operations Affected
(Flight Crew Operations Manual and/or
FAA Approved Airplane Flight Manual)
Paragraph 2.C.1., Kits/PartsYesKits/Parts Required
Paragraph 2.C.2., Parts and Materials Supplied
by the Operator
YesOperator Supplied Material
Paragraph 2.F., Special Tooling Necessary to
do this Service Bulletin
NoSpecial Tooling Required
ACTION (PRR 23907, PRR 24826-R)
Do a detailed and High Frequency Eddy Current (HFEC) inspection of the foreflap carriage attach fittings for
any crack or damage. If any crack or damage is found, replace the carriage attach fitting. If no crack or damage
is found, do the repeat inspections at the interval given in Paragraph 1.E., Compliance .
Incorporate the service bulletins listed in Paragraph 1.B., Concurrent Requirements .
– For the inboard foreflap, installation of the improved carriage attach fittings and incorporation of the service
bulletins listed in Paragraph 1.B., Concurrent Requirements terminates the repeat inspections.
– For the outboard foreflap, installation of the improved carriage attach fittings and incorporation of the service
bulletins listed in Paragraph 1.B., Concurrent Requirements decreases the frequency of the repeat
inspections.
Do a one-time clearance/interference check of the carriage attach fitting. Shim if required. If interference is found,
rework the carriage attach lug.
On airplanes with the production carriage attach fitting, replace the production carriage attach fitting with the
improved carriage attach fitting and incorporate the service bulletins listed in Paragraph 1.B., Concurrent
Requirements . For the outboard foreflap the installation of the improved carriage attach fittings and the
incorporation of the service bulletins listed in Paragraph 1.B., Concurrent Requirements , is not a terminating
action.
For the outboard foreflap, do general visual inspections and functionality check of the outboard foreflap installation
for damage and incorrect operation.
Export Controlled ECCN: 9E991 - BOEING
PROPRIETARY - Copyright © Unpublished
Work - See page 1 for details.
Original Issue: February 07, 1975
727-57A0135Revision 4: September 26, 2012
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BOEING SERVICE BULLETIN 727-57A0135
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### Page 9

EFFECTIVITY
All 727, 727-100, 727-100C, 727-200, 727-200F, 727C Airplanes. Refer to Paragraph 1.A.1., Airplanes, for the
list of affected airplanes.
COMPLIANCE
Federal Aviation Administration (FAA) Airworthiness Directive AD 2005-14-07 is related to this service bulletin.
Refer to Paragraph 1.E., Compliance.
INDUSTRY SUPPORT INFORMATION
Boeing warranty remedies are not available for the configuration changes, inspection, and/or repair procedures
given in this service bulletin.
MANPOWER
Refer to Paragraph 1.G., Manpower.
MATERIAL INFORMATION
Boeing Supplied Kits/Parts.
Refer to Paragraph 2.A., Material - Price and Availability.
Export Controlled ECCN: 9E991 - BOEING
PROPRIETARY - Copyright © Unpublished
Work - See page 1 for details.
Original Issue: February 07, 1975
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BOEING SERVICE BULLETIN 727-57A0135
ALERTALERT

### Page 10 (OCR)

BOEING SERVICE BULLETIN 727-57A0135
ALERT  ALERT
FOREFLAP
FOREFLAP  SEQUENCING
CARRIAGE  CARRIAGE
ATTACH FITTING
SEE Q
MIDFLAP
FLAP TRACK  FLAP CARRIAGE
FOREFLAP  SEQUENCING
TOGGLE  FWDS
OUTBOARD TRAILING EDGE FLAP INSTALLATION
(TYPICAL FOR INBOARD AND OUTBOARD FOREFLAP)
TYPICAL
Original Issue: February 07, 1975
Revision 4: September 26, 2012
CARRIAGE
ATTACH LUG
CARRIAGE ATTACH FITTING:
INSPECT FOR ANY CRACK OR DAMAGE
(TWO PLACES ON EACH FORFLAP)
PROPRIETARY - Copyright © Unpublished  Export Controlled ECCN: 9E991 - BOEING  727-57A0135
Work - See page 1 for details.  10 of 37

### Page 11

Commercial 
Airplanes
727
Service Bulletin
ALERT
Number: 727-57A0135
Original Issue: February 07, 1975
Revision 4: September 26, 2012
ATA System: 5742
SUBJECT: ATTACH FITTINGS Flight Control - Foreflap Carriage Attachment Inspection And
Adjustment
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 D6-9825 Part 3 for Airplane Variable Number, Line Number, and
Serial Number data.
DESCRIPTIONCONFIGURATIONGROUP
727, 727-100, 100C, 200, 200F, 727C airplanes line numbers 1 thru
1832.
-1
Airplane Models:
727, 727-100, 727-100C, 727-200, 727-200F, 727C
GroupVariable Number
1E0001 - E0042
1E0101 - E0140
1E0201 - E0216
1E0301 - E0351
1E0401 - E0423
1E3001 - E3006
1E3011 - E3014
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GroupVariable Number
1E3021 - E3040
1E3059
1E3061 - E3077
1E3101 - E3103
1E3111 - E3118
1E3141 - E3152
1E3171 - E3177
1E3201 - E3206
1E3221 - E3224
1E3241 - E3290
1E3341 - E3350
1E3401 - E3421
1E3451 - E3452
1E3471 - E3474
1E3501 - E3513
1E3516 - E3523
1E3551 - E3553
1E3571 - E3578
1E3601 - E3604
1E3621 - E3622
1E3651 - E3655
1E3677
1E3681 - E3684
1E3701 - E3704
1E3751 - E3755
1E3781 - E3784
1E5001 - E5011
1E5031 - E5068
1E5101 - E5116
1E5141 - E5143
1E5161 - E5164
1E5201 - E5203
1E5221 - E5245
Export Controlled ECCN: 9E991 - BOEING
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Original Issue: February 07, 1975
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GroupVariable Number
1E5251 - E5252
1E5271 - E5281
1E5301 - E5306
1E5351 - E5353
1E5381 - E5382
1E5401 - E5424
1E5426 - E5429
1E5433
1E5435
1E5451 - E5455
1E5481 - E5483
1E5501 - E5502
1QA001 - QA046
1QA051 - QA099
1QA101 - QA199
1QA201 - QA225
1QA301 - QA349
1QA351 - QA376
1QA378
1QA401 - QA499
1QA501 - QA537
1QA551 - QA579
1QA581 - QA585
1QA601 - QA688
1QA701 - QA753
1QA801 - QA805
1QA851 - QA899
1QA901 - QA946
1QA949
1QB001 - QB002
1QB031 - QB049
1QB051 - QB068
1QB101 - QB110
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GroupVariable Number
1QB114 - QB119
1QB121 - QB149
1QB151 - QB158
1QB201 - QB220
1QB301 - QB316
1QB351 - QB352
1QB401 - QB407
1QB451 - QB458
1QB501 - QB575
1QB601 - QB629
1QB651
1QB701 - QB705
1QB801 - QB810
1QB901 - QB904
1QD001 - QD012
1QD031 - QD046
1QD085 - QD088
1QD101 - QD105
1QD121 - QD127
1QD141 - QD149
1QD161 - QD164
1QD191 - QD192
1QD201 - QD239
1QD281 - QD284
1QD301 - QD305
1QD321 - QD330
1QD351
1QD401 - QD403
1QD407
1QD410
1QD421 - QD427
1QD441 - QD453
1QD471 - QD475
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GroupVariable Number
1QD501 - QD518
1QD551 - QD558
1QD571 - QD572
1QD581 - QD583
1QD601 - QD607
1QD621 - QD624
1QD641
1QD661 - QD663
1QD681 - QD685
1QD691 - QD692
1QD701 - QD702
1QD711 - QD717
1QD741
1QD761 - QD769
1QD781 - QD782
1QD791
1QD801 - QD804
1QD821 - QD828
1QD901 - QD910
1QD931 - QD932
1QD951 - QD954
1QD971 - QD973
1QD991 - QD992
1QE001 - QE002
1QL001 - QL008
1QL031 - QL032
1QL081
1QL501 - QL515
2. Spares Affected
Examine your spares supply for the parts or components identified below. If any parts or components
are found, refer to Accomplishment Instructions paragraph 3.B.2.b. for the recommended action.
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### Page 16

Part Number
69-26255-3
69-26255-4
69-26256-1
69-26256-2
69-26257-1
69-26257-2
B. Concurrent Requirements
The service bulletins listed below must be done before or at the same time as this service bulletin:
DescriptionService BulletinCompany
Outboard Trailing Edge Foreflap Track Guide
Block Installation.
727-57-0059 Revision 01.Boeing
Foreflap Track Modification.727-57-0072 Original issue.Boeing
Outboard Trailing Edge Foreflap Rigging and
Jackscrew Modification at 40 Degrees Posi-
tion.
727-27-0133 Revision 01.Boeing
NOTE: The components in the concurrent service bulletins are interchangeable between 727 airplanes.
As such, Boeing recommends the inspection of each component, as given in the applicable
service bulletin (for all 727 airplanes and spares inventory), to decide if it has been modified.
C. Reason
This service bulletin gives instructions to inspect the carriage attach fittings of the inboard and outboard
foreflaps for any crack or damage. Fleet service information and analysis show that repeat inspections
or replacement of the carriage attach fittings decrease the risk of partial or complete foreflap loss caused
by fatigue. Inspection and adjustment, if necessary, of the gap between the foreflap carriage attach
fitting and the carriage lug on the inboard and outboard foreflap assemblies will decrease the possibility
of fatigue failure of the carriage attach fittings from excessive clamp-up. The fatigue life of the new
replacement fittings increased with the design of thicker flanges, and a material change to Corrosion
Resistant Steel. If the work in this service bulletin is not done, breakage of the carriage attach fittings
can result in the loss of the foreflap and damage to adjacent structures which could lead to loss of
controllability of the airplane during take-off and landing.
Sixteen operators reported twenty-eight failed or damaged outboard foreflaps with the attach fitting of
the Foreflap Sequencing Carriage cracked or failed. In the first fourteen instances the foreflap failures
were attributed to a flap overextension condition. Service bulletins 727-57-0059, 727-57-0072 and
727-27-0133 were issued to correct this and other related conditions.
A recent failure could not be attributed to the overextension condition. Analysis indicated that the fitting
had failed in fatigue. A review of the dimensional tolerances at the carriage attach lug and the carriage
attach fitting showed that very high clamp-up stresses are possible under the most adverse tolerance
conditions. High clamp-up stresses combined with airloads can cause fatigue cracks.
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ALERTALERT

### Page 17

As a result of the findings, it is suggested that operators inspect, and if necessary, reduce the clamp-up
of the attach fitting in addition to correcting foreflap overextension and related condition given in the
earlier service bulletins.
Subsequent to release of the original issue of the service bulletin, a review of manufacturing records
show that the full intent of the service bulletin was incorporated on a number of Group II airplanes in
production. On other Group II airplanes, however, the intent of the service bulletin was accomplished
on the inboard foreflap instead of the outboard foreflap or had been accomplished on neither.
It has also been noted that reverse dimensional tolerance at the carriage attach lug and carriage attach
fitting could result in interference, as opposed to excessive gap and clamp-up.
Boeing Service Related Problem (SRP) 727-SRP-57-0128 and 727-SRP-57-0243  are related to this
service bulletin.
Revision 1 was issued to advise inspection for interference in addition to inspection for clamp-up, to
delete a number of Group II airplanes from the effectivity, to transfer a number of airplanes from Group
II to Group I, and to advise inspections of the outboard foreflaps instead of the inboard foreflaps on the
remaining Group II airplanes.
Revision 2 changed the penetrant inspection to magnetic particle inspection and added an examination
of the carriage attach fitting clevis. Revision 2 also added all remaining 727 airplanes to the effectivity
because of interchangeability of flaps among airplanes. Because of flap interchangeability, airplanes
are no longer in two groups as given in previous issues of this service bulletin.
Revision 3 changed this service bulletin to Alert status. This revision also provides specific inspection
intervals for the carriage attach fittings. The added inspections make it easier to find cracks that start
at the bore of the upper bolt hole or the forward edge of the lug. High-Frequency Eddy Current (HFEC)
Inspections replace the Penetrant Inspection used in Revision 2. As a result of these changes, the
layout of the service bulletin is different. That is, Figures 2 and 3 and 4 are added to the Accomplishment
Instructions. Figure 2 contains the clearance and/or interference checks, and Figure 3 is the rework of
the carriage attach lug. Figure 4 provides installation for the improved fitting for the Outboard Foreflap
at WBL 348 since a new bolt type is used than what is shown in the Overhaul Manual for that location.
The improved fittings have the same foot print as the existing fittings; however, the clevis lugs are
thicker and material is now Corrosion Resistant Steel.
Revision 4 is sent to increase the frequency of the repeat High Frequency Eddy Current (HFEC)
inspection of production outboard foreflap carriage attach fittings, make compulsory the installation of
the improved outboard foreflap carriage attach fittings, make incorporation of the concurrent service
bulletins compulsory, add a general visual inspection and functionality check of the outboard foreflap
and to require repeat inspections of the improved outboard foreflap carriage attach fittings.
Since the release of Revision 2, Boeing received 5 reports of foreflap loss from 3 operators. In early
revisions of this service bulletin, the total number of reports included all occurrences related to foreflap
overextension and the carriage attach fitting. This service bulletin is only applicable to the carriage
attach fitting. The service bulletins given in Paragraph 1.B., Concurrent Requirements, are applicable
to foreflap also.
Since the release of Revision 3, one operator has reported that during a scheduled inspection per
Federal Aviation Administration (FAA) Airworthiness Directive AD 2005-14-07 , both inboard and
outboard Foreflap Carriage Fittings were found broken. The event occurred at 47,125 Flight Cycles.
Metallurgical analysis determined that the cause of the broken fittings is a suspected static overload
condition.
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D. Description
Revision 4 - More work is necessary on the airplanes changed in accordance with Revision 3 of this
service bulletin. For the outboard foreflap, replace the production carriage attach fittings with the new
improved carriage attach fittings at the time given in Paragraph 1.E., Compliance . Continue to inspect
the carriage attach fittings at the interval given in Paragraph 1.E., Compliance .
Revision 3 - more work is necessary on airplanes changed by Revision 2 because there are more
frequent inspections of the carriage attach fitting.
Revision 2 - more work was necessary on airplanes changed as shown in Revision 1 or the original
release of this service bulletin because of flap interchangeability among airplanes. Revision 2
recommended the inspection of the inboard and outboard foreflaps on all 727 airplanes.
Do a detailed and High Frequency Eddy Current (HFEC) inspection of the foreflap carriage attach
fittings for any crack or damage. If any crack or damage is found, replace the carriage attach fitting. If
no crack or damage is found, do the repeat inspections at the interval given in Paragraph 1.E.,
Compliance .
Incorporate the service bulletins listed in Paragraph 1.B., Concurrent Requirements .
– For the inboard foreflap, installation of the improved carriage attach fittings and incorporation of
the service bulletins listed in Paragraph 1.B., Concurrent Requirements terminates the repeat
inspections.
– For the outboard foreflap, installation of the improved carriage attach fittings and incorporation of
the service bulletins listed in Paragraph 1.B., Concurrent Requirements decreases the frequency
of the repeat inspections.
Do a one-time clearance/interference check of the carriage attach fitting. Shim if required. If interference
is found, rework the carriage attach lug.
On airplanes with the production carriage attach fitting, replace the production carriage attach fittings
with the improved carriage attach fittings and incorporate the service bulletins listed in Paragraph 1.B.,
Concurrent Requirements. For the outboard foreflap the installation of the improved carriage attach
fittings and the incorporation of the service bulletins listed in Paragraph 1.B., Concurrent Requirements,
is not a terminating action.
For the outboard foreflap, do general visual inspections and functionality check of the outboard foreflap
installation for damage and incorrect operation.
The work in this service bulletin is done in the maintenance zone(s) given below.
Affected Maintenance Zones
ZoneModel
5-82, 5-84, 6-85, 6-87727, 727-100, 727-100C, 727-
200, 727-200F, 727C
E. Compliance
Federal Aviation Administration (FAA) Airworthiness Directive AD 2005-14-07 is related to this service
bulletin.
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Boeing recommends that you do the inspection in Figure 1 within 1,000 flight cycles after the Revision
3 date of this service bulletin or within 6 months from the Revision 4 date of this service bulletin,
whichever occurs first. If any crack or damage is found in the carriage attach fitting, replace the carriage
attach fitting in accordance with Accomplishment Instructions paragraph 3.B.2.b. before further flight.
Boeing also recommends that you do the one-time check in Figure 2 and the service bulletins listed in
Paragraph 1.B., Concurrent Requirements within 3,500 flight cycles after the Revision 3 date of this
service bulletin.
For the inboard foreflap, continue to do the inspections in accordance with Figure 1 at intervals not to
exceed 1,000 flight cycles. If any crack or damage is found in the carriage attach fitting, replace the
carriage attach fitting in accordance with Accomplishment Instructions paragraph 3.B.2.b. before further
flight. Do the repeat inspections until the carriage attach fitting is replaced as provided below:
– If a new carriage attach fitting, of the old configuration, from Boeing Spares is installed (never been
in service), as provided in Revision 3 and subsequent revisions of this service bulletin, and the
service bulletins listed in Paragraph 1.B., Concurrent Requirements are incorporated, inspect the
carriage attach fitting again in accordance with Figure 1 within 10,000 flight cycles. Thereafter,
continue to do the inspections in accordance with Figure 1 at intervals not to exceed 1,000 flight
cycles.
– When an improved carriage attach fitting is installed, in accordance with Revision 3 and subsequent
revisions of this service bulletin, and the service bulletins listed in Paragraph 1.B., Concurrent
Requirements are incorporated, no more inspections of the inboard foreflap carriage attach fittings
by this service bulletin are necessary.
For the outboard foreflap, continue to do the inspections in accordance with Figure 1 at intervals not
to exceed 200 flight cycles, until the carriage attach fitting is replaced as provided below:
– On airplanes with the production carriage attach fitting, replace the production carriage attach
fitting with an improved carriage attach fitting in accordance with Accomplishment Instructions
paragraph 3.B.2.b. and incorporate the service bulletins listed in Paragraph 1.B., Concurrent
Requirements, within 3,000 flight cycles or three years after the Revision 4 date of this service
bulletin, whichever comes first.
– If a new carriage attach fitting, of the old configuration, from Boeing Spares is installed (never been
in service), in accordance with Revision 3 and subsequent revisions of this service bulletin, and
the service bulletins listed in Paragraph 1.B., Concurrent Requirements are incorporated, inspect
the carriage attach fitting again in accordance with Figure 1 within 1,000 flight cycles after the
Revision 4 date of this service bulletin. Thereafter continue to do the inspections in accordance
with Figure 1 at intervals not to exceed 200 flight cycles. Replace the carriage attach fitting with
an improved carriage attach fitting in accordance with Accomplishment Instructions paragraph
3.B.2.b. and incorporate the service bulletins listed in Paragraph 1.B., Concurrent Requirements,
within 3,000 flight cycles or three years after the Revision 4 date of this service bulletin, whichever
comes first.
– When an improved carriage attach fitting is installed, as provided in Revision 3 and subsequent
revisions of this service bulletin, inspect the carriage attach fitting in accordance with Figure 1
within 20,000 flight cycles after installation of the improved carriage attach fitting. Thereafter
continue to do the inspections in accordance with Figure 1 at intervals not to exceed 1,400 flight
cycles. Note that installation of the improved carriage attach fittings on the outboard flap and the
incorporation of the service bulletins in Paragraph 1.B., Concurrent Requirements, is not terminating
action.
– If any crack or damage is found in the carriage attach fitting when doing a repeat inspection, replace
the carriage attach fitting in accordance with Accomplishment Instructions paragraph 3.B.2.b.
before further flight.
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If a component in Boeing Service Bulletin 727-57-0059, 727-57-0072 or 727-27-0133 is removed from
the airplane and replaced with a different component (new or overhauled), make sure it agrees with
the approved conditions in that applicable service bulletin.
NOTE: An improved carriage attach fitting is specified by the part numbers given in Paragraph 2.C.,
Parts Necessary for Each Airplane.
For the outboard foreflap only, do a general visual inspection and functionality check of the outboard
foreflap installation for damage and incorrect operation in accordance with Accomplishment Instructions
paragraph 3.B.4. within 200 flight cycles or 6 months after the Revision 4 date of this service bulletin,
whichever occurs first. If any damage or incorrect operation is found, replace the sequence carriage
slider and/or sidewall rubstrips in accordance with Accomplishment Instructions paragraph 3.B.4.a.
Repeat the general visual inspection and functionality check at intervals not to exceed 500 flight cycles.
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.
The Manager of the FAA Seattle Aircraft Certification Office approves the inspections, repair/modification
and replacement of the foreflap carriage attachment fittings, defined in SB 727-57A0135, Revision 4,
as an alternative method of compliance to the inspections, repair/modification and replacement of the
foreflap carriage attachment fittings, defined in SB 727-57A0135, Revision 3, dated June 27, 2002,
and required by paragraphs (f), (g), (h), (i), (n) and (o) of AD 2005-14-07. When this service bulletin
specifies contacting Boeing for repair instructions, the repair instructions must be approved by the FAA
in accordance with paragraph (i) of the AD. All provisions of AD 2005-14-07 that are not specifically
referenced in the above statement remain fully applicable and must be complied with accordingly.
If an airplane has a non-Boeing modification or repair that affects a component or system also affected
by this service bulletin, the operator is responsible for obtaining appropriate regulatory agency approval
before incorporating this service bulletin.
G. Manpower
The table below shows an estimate of the task hours necessary to do this 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 inspect the work
 Time to cure the materials
 Time to make the parts
 Time to find the tools.
NOTE: This estimate does not include the man-hour data for work done in service bulletins
727-57-0059, 727-57-0072 or 727-27-0133.
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Elapsed HoursTask HoursNumber of Per-
sons
Task
0.500.501Open Access
2.00 (a)4.002Visual / HFEC Inspection
0.75 (b)0.751Fitting Replacement
1.00 (c)2.002Fit / Trim
0.500.501Close Access
1.001.001General Visual Inspection and
Functionality Check
0.501.002Test (operational)
6.759.75TOTAL FOR EACH AIRPLANE
(a) All fittings.
(b) Each Fitting.
(c) Each foreflap.
H. Weight and Balance Changes
None.
I. Electrical Load Data
Not applicable.
J. References
1. Existing Data:
a. Engineering Change Memo PRR 23907, PRR 24826-R.
b. Boeing Service Bulletin 727-27-0133, 727-57-0059, 727-57-0072.
c. Boeing Service Related Problem (SRP) 727-SRP-57-0128, 727-SRP-57-0243 .
d. Federal Aviation Administration (FAA) Airworthiness Directive (AD) 2005-14-07.
e. Overhaul Manual (OHM) 57-52-01, 57-52-11.
f. Service Bulletin Index D6-9825.
g. Standard Overhaul Practices Manual (SOPM) 20-10-02, 20-10-03, 20-20-01, 20-30-03,
20-41-02, 20-42-10.
h. 727 Aircraft Maintenance Manual (AMM) 727 AMM 27-51-00, 27-51-04, 27-51-14.
i. 727 Non-Destructive Testing (NDT) Manual Part 6, 51-00-00, Figure 2 and Part 6, 57-40-27,
Figure 3.
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2. Data Supplied with this Service Bulletin:
None.
3. Installation Drawings Used in the Preparation of this Service Bulletin:
TitleDrawing Number
Fore Flap - Outboard Flap, Assy of65-21631, Sht 4
The table above lists applicable drawings used to prepare this service bulletin. The drawings are
not necessary to make the specified changes, and are not supplied with this service bulletin. The
drawings may not be applicable to all airplane configurations or operators.
K. Publications Affected
1. Publications:
Chapter-SectionPublication
57-52727 Operations Manual
57-53727 Illustrated Parts Catalog
57-52727 Component Maintenance Manual
2. Damage Tolerance Based Structural Inspections:
Boeing has evaluated the repairs and/or changes in this service bulletin for effects on Fatigue
Critical Structure (FCS) and for changes to Damage Tolerance Inspections (DTI) required in the
Maintenance Program. This service bulletin affects FCS and new DTI requirements for the structure
affected are contained in Paragraph 1.E., Compliance of this service bulletin.
L. Interchangeability and Intermixability of Parts
Refer to Paragraph 2.C., Parts Necessary for Each Airplane, for interchangeability and intermixability
information.
M. Software Accomplishment Summary
Not affected.
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2.    MATERIAL INFORMATION
A. Material - Price and Availability
The operator can supply the parts and materials shown in Paragraph 2.C., Parts Necessary for Each
Airplane and Paragraph 2.D., Parts Necessary to Change Spares. As an alternative, operators can
purchase the parts from Boeing Spares. This service bulletin does not show the Boeing price and
supply data.
B. Industry Support Information
Boeing warranty remedies are not available for the configuration changes, inspection, and/or repair
procedures given in this service bulletin.
C. Parts Necessary for Each Airplane
1. Kits/Parts
To get the parts shown below, refer to Paragraph 2.A., Material - Price and Availability.
NamePart NUmberQTY
Shim LaminatedBACS40R007U015 (or
equivalent)
As Necessary
Outboard Foreflap Carriage Attach
Fitting - WBL 348
69-26255-5 Left Wing1
Outboard Foreflap Carriage Attach
Fitting - WBL 348
69-26255-6 Right Wing, op-
posite
1
Outboard Foreflap Carriage Attach
Fitting - WBL 442
69-26256-3 Left Wing1
Outboard Foreflap Carriage Attach
Fitting - WBL 442
69-26256-4 Right Wing, op-
posite
1
Inboard Foreflap Carriage Attach
Fitting - WBL 124 & 224
69-26257-3 Left Wing2
Inboard Foreflap Carriage Attach
Fitting - WBL 124 & 224
69-26257-4 Right Wing, op-
posite
2
Bolt for Outboard fitting - WBL 348
(Figure 4)
BACB30VF4K62
Bolt - Lug/ClevisBACB30ZB4-84
Bolt - Lug/ClevisBACB30ZB5-84
Bolt - Lug/ClevisBACB30ZB4-88
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2. Parts and Materials Supplied by the Operator
NotesNameQTYPart Number / Speci-
fication
-Shim laminatedAs NecessaryBACS40R007U015
(or equivalent)
-PrimerAs NecessaryBMS 10-11, Type 1
-Gray EnamelAs NecessaryBMS 10-11, Type 2
3. Parts Modified and Reidentified
NotesNew Part NumberNameQTYExisting Part
Number
(a) (b) (c)69-26255-5Outboard Foreflap,
Carriage Fitting, Left
Wing (BL348)
169-26255-3
(a) (b) (c)69-26255-6Outboard Foreflap,
Carriage Fitting, Right
Wing (BL348)
169-26255-4
(a) (b) (c)69-26256-3Outboard Foreflap,
Carriage Fitting, Left
Wing (BL442)
169-26256-1
(a) (b) (c)69-26256-4Outboard Foreflap,
Carriage Fitting, Right
Wing (BL442)
169-26256-2
(a) (b) (c)69-26257-3Inboard Foreflap, Car-
riage Fitting, Left Wing
(BL 124 & 224)
269-26257-1
(a) (b) (c)69-26257-4Inboard Foreflap, Car-
riage Fitting, Right Wing
(BL 124 & 224)
269-26257-2
(a) Discard the existing part (after hole transfer location is made to the new part).
(b) This is the part number for the new equivalent or replacement part. To get a new part, use
this part number in your order.
(c) Do not use the existing part to replace the new or changed part.
4. Parts Removed and Not Replaced
None.
D. Parts Necessary to Change Spares
To get the parts shown below, refer to Paragraph 2.A., Material - Price and Availability.
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NamePart NumberQTY
Shim LaminatedBACS40R007U015 (or
equivalent)
As Necessary
Outboard Foreflap Carriage Attach
Fitting - WBL 348
69-26255-5 Left Wing1
Outboard Foreflap Carriage Attach
Fitting - WBL 348
69-26255-6 Right Wing, op-
posite
1
Outboard Foreflap Carriage Attach
Fitting - WBL 442
69-26256-3 Left Wing1
Outboard Foreflap Carriage Attach
Fitting - WBL 442
69-26256-4 Right Wing, op-
posite
1
Inboard Foreflap Carriage Attach
Fitting - WBL 124 & 224
69-26257-3 Left Wing2
Inboard Foreflap Carriage Attach
Fitting - WBL 124 & 224
69-26257-4 Right Wing, op-
posite
2
Bolt for Outboard fitting - WBL 348
(Figure 4)
BACB30VF4K62
Bolt - Lug/ClevisBACB30ZB4-84
Bolt - Lug/ClevisBACB30ZB5-84
Bolt - Lug/ClevisBACB30ZB4-88
E. Special Tooling - Price and Availability
None.
F. Special Tooling Necessary to do this Service Bulletin
No special tools or equipment are necessary to do the change in this service bulletin. But, maintenance
and overhaul tools in the manuals given in Paragraph 1.J., References, can be necessary. Examine
operator tool supply to make sure all necessary tools are available.
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3.    ACCOMPLISHMENT INSTRUCTIONS
A. GENERAL INFORMATION
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. Manual titles are referred to by acronyms. Refer to Paragraph 1.J., References , for
definition of the acronyms.
2. Obey all of the warnings and cautions given in the specified manual sections.
3. Unless shown differently, these dimensions and tolerances are used:
– Torque limits to tighten nuts and bolts are in SRM Chapter 51.
4. Use the approved fastener and process material substitutions in accordance with
SRM Chapter 51.
5. 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.
6. 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.
7. A General Visual Inspection is defined as: A visual examination of an interior or
exterior area, installation or assembly to detect obvious damage, failure or irregularity.
This level of inspection is made from within touching distance unless otherwise
specified. A mirror may be necessary to enhance visual access to all exposed surfaces
in the inspection area. This level of inspection is made under normally available
lighting conditions such as daylight, hangar lighting, flashlight or drop-light and may
require removal or opening of access panels or doors. Stands, ladders or platforms
may be required to gain proximity to the area being checked.
8. These work instructions refer to procedures included in other Boeing documents.
When the words "refer to" are used and the operator has an accepted alternative
procedure, the accepted alternative procedure can be used. When the words "in
accordance with" are included in the instruction, the procedure in the Boeing document
must be used.
9. Boeing Service Letter 727-SL-51-041, Damage Reporting and Repair Plan/Design
Guidelines, is an acceptable procedure to request information from Boeing for
additional structural repair instructions. The Service Letter describes what information
must be provided to Boeing before a structural repair can be provided.
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10. If it is necessary to remove more parts for access, you can remove those parts. If
you can get access without removing identified parts, it is not necessary to remove
all of the identified parts. Jacking and shoring limitations must be observed.
11. 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.
12. This service bulletin includes functional test procedures for the systems changed by
this service bulletin. More functional tests can possibly be necessary in accordance
with standard maintenance practices because of interruption to other airplane systems.
B. WORK INSTRUCTIONS
1. Provide system A hydraulic power (reference 727 AMM 27-51-00 ) and extend the inboard and
outboard trailing edge flaps. Then, remove system A hydraulic power. Refer to 727 AMM 27-51-00
as an accepted procedure. At the P6 circuit breaker panel, OPEN the FLAP breaker and place a
"Do-Not-Disturb" placard at this breaker. Support the Foreflap in its extended position.
2. Inspect the two carriage attach fittings on the inboard and outboard Foreflaps, of each wing, in
accordance with Figure 1.
a. If no cracking is found, continue on with Paragraph 3 (note compliance time for this
requirement).
b. If any crack is found, remove the carriage attach fitting from the Foreflap. The Foreflap
Sequencing Carriage will first have to be removed. Refer to 727 AMM 27-51-04  (Inboard
Flap) and 727 AMM 27-51-14 (Outboard Flap) as an accepted procedure for carriage removal.
Then remove the carriage attach fitting. Refer to OHM 57-52-11 (Outboard T.E. Flap) and
OHM 57-52-01 (Inboard T.E. Flap) as an accepted procedure. Transfer the mounting holes
from the removed carriage attach fitting to its replacement carriage attach fitting (The fittings
are unique to their location.).
(1) If you install an existing part number carriage attach fitting on the inboard and/or outboard
Foreflaps, refer to OHM 57-52-11 (Outboard T.E. Flap) and OHM 57-52-01 (Inboard T.E.
Flap) as an accepted procedure for installation. Refer to Paragraph 1.E., Compliance for
continued inspections of the old fitting until the improved fitting is installed on the Foreflap.
(2) If you install an improved carriage attach fitting (reference Existing Parts Accountability),
install as follows:
(a) For the two locations on the inboard (WBL 124 / WBL 224) Foreflap, refer to OHM
57-52-01 (Inboard T.E. Flap) as an accepted procedure for installation. When
attaching the carriage lug to the improved fitting, remember that due to the increase
flange thicknesses of the clevis, install a longer bolt when you attach the lug to the
clevis as follows:
– Upper clevis hole: NAS1104-8 or BACB30ZB4-8.
– Lower clevis hole: NAS1105-8 or BACB30ZB5-8.
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(b) For the WBL 442 outboard location on the outboard Foreflap, refer to OHM 57-52-11
(Outboard T.E. Flap) as an accepted procedure for installation. When attaching the
carriage lug to the improved fitting, remember that due to the increase flange
thicknesses of the clevis, install a longer bolt when you attach the lug to the clevis.
Use bolt NAS1104-8 or BACB30ZB4-8 at the upper and lower clevis hole locations.
(c) For the WBL 348 (most inboard) location on the outboard Foreflap, refer to OHM
57-52-11 (Outboard T.E. Flap) as an accepted procedure for installation, except for
one bolt location (aft outboard) install in accordance with Figure 4.
When attaching the carriage lug to the improved fitting, remember that due to the
increase flange thicknesses of the clevis, install a longer bolt when you attach the
lug to the clevis. Use bolt NAS1104-8 or BACB30ZB4-8 at the upper and lower clevis
hole locations.
c. Reinstall the Foreflap Sequencing Carriage. Refer to 727 AMM 27-51-04  (Inboard Flap) and
727 AMM 27-51-14 (Outboard Flap) as an accepted procedure. Then continue on with
Paragraph 3.
3. Measure the distance between the carriage attach fitting and the carriage lug fitting in accordance
with Figure 2.
a. If the clearance is between 0.000 inch and 0.003 inch, no more work is necessary. Install the
bolt.
b. If the clearance is more than 0.003 inch, add a shim. Install BACS40R007U015. Remove
laminations, as necessary. Apply 2 layers of Primer (BMS 10-11, Type 1) and 1 layer of Enamel
(BMS 10-11, Type 2). Refer to SOPM 20-41-02 as an accepted procedure.
c. If interference is found, rework the carriage attach lug in accordance with Figure 3.
4. For the outboard foreflap only, do a general visual inspection and functionality check of the outbd
foreflap installation for damage and incorrect operation. Refer to 727 AMM 27-51-14 as an accepted
procedure.
a. If any damage or incorrect operation is found, replace the sequence carriage slider and/or
sidewall rubstrips as required. Refer to 727 AMM 27-51-14 as an accepted procedure.
b. If no damage is found and the flap operates correctly, repeat the general visual inspection
and functionality check of the flap system at the interval given in Paragraph 1.E., Compliance.
5. Put the airplane back to a condition that is approved for service.
Export Controlled ECCN: 9E991 - BOEING
PROPRIETARY - Copyright © Unpublished
Work - See page 1 for details.
Original Issue: February 07, 1975
727-57A0135Revision 4: September 26, 2012
29 of 37
BOEING SERVICE BULLETIN 727-57A0135
ALERTALERT

### Page 30 (OCR)

BOEING SERVICE BULLETIN 727-57A0135
ALERT  ALERT
FOREFLAP
FOREFLAP
SEQUENCING
CARRIAGE  CARRIAGE
ATTACH FITTING
SEE
MIDFLAP
• FLAP TRACK  FLAP CARRIAGE
TOGGLE
OUTBOARD TRAILING EDGE FLAP INSTALLATION
(TYPICAL FOR INBOARD AND OUTBOARD FOREFLAP)
23
CARRIAGE  CONTACH FELTING
ATTACH LUG
FWD T
TYPICAL
FIGURE 1: INSPECTION
(SHEET 1 OF 2)
Original Issue: February 07, 1975
Revision 4 September 26, 2012  Export Controlled ECCN: 9E991 - BOEING  PROPRIETARY - Copyright © Unpublished  727-57A0135
Work - See page 1 for details.  30 of 37

### Page 31

The step numbers shown below agree with the numbers shown in the circle symbols in the figure. The QTY
numbers shown below are the numbers of parts necessary for one fitting.
NOTESPROCEDURENAMETASKSTEP
Keep the parts to use
again if they are in
an approved condi-
tion for service.
-Bolt, Washer, NutRemove / Keep1
Look for any crack or
surface deviation on
all edges, surfaces
and holes. (a)
Detailed InspectionHole, Base Radius,
Lug Face, forward
edge
Inspect2
Look for any crack in
accordance with 727
NDT Part 6, 51-00-
00, Figure 2.
High Frequency Ed-
dy Current
HoleInspect3
Look for any crack in
accordance with 727
NDT Part 6, 57-40-
27, Figure 3.
High Frequency Ed-
dy Current
Hole, Base Radius,
Lug Face, forward
edge
Inspect4
If there is no crack, reinstall the bolt, washer and nut.
(a) Nicks, scratches or dents are NOT permitted on the forward surface or in the hole. If found, replace the
fitting. The lug surface finish must be 125 microinches or better.
FIGURE 1: INSPECTION
(SHEET 2 OF 2)
Export Controlled ECCN: 9E991 - BOEING
PROPRIETARY - Copyright © Unpublished
Work - See page 1 for details.
Original Issue: February 07, 1975
727-57A0135Revision 4 September 26, 2012
31 of 37
BOEING SERVICE BULLETIN 727-57A0135
ALERTALERT

### Page 32 (OCR)

BOEING SERVICE BULLETIN 727-57A0135
ALERT  ALERT
FOREFLAP
FOREFLAP
SEQUENCING
CARRIAGE  CARRIAGE
ATTACH FITTING
SEE I
MIDFLAP
> FLAP TRACK  FLAP CARRIAGE
SEQUENCING
TOGGLE
OUTBOARD TRAILING EDGE FLAP INSTALLATION
(TYPICAL FOR INBOARD AND OUTBOARD FOREFLAP)
FOREFLAP
2) RADIUS
RADIUS 2
•CARRIAGE  CARRIAGE
ATTACH  ATTACH
FITTING  FITTING
CARRIAGE
ATTACH LUG
FWD <
CARRIAGE
ATTACH LUG
→ INBD
TYPICAL  A-A  V46359
FIGURE 2: CHECK FOR CLEARANCE/INTERFERENCE
(SHEET 1 OF 2)
Original Issue: February 07, 1975
Revision 4 September 26, 2012  Export Controlled ECCN: 9E991 - BOEING  PROPRIETARY - Copyright © Unpublished  727-57A0135
Work - See page 1 for details.  32 of 37

### Page 33

The step numbers shown below agree with the numbers shown in the circle symbols in the figure. The QTY
numbers shown below are the numbers of parts necessary for one fitting.
NOTESQTYPART NUMBERNAMETASKSTEP
Minimum permitted thickness is
0.09 inch for existing fitting (non-
improved fitting) configuration.
2-DistanceMeasure /
Record
1
Minimum permitted radius is 0.09
inch for existing fitting (non-im-
proved fitting) configuration.
2-RadiusMeasure /
Record
2
Maximum permitted finish is 125
micro inches. (a)
--Surface FinishInspect /
Record
3
Between the attach fitting clevis and
the carriage attach lug. (b)
--Clearance /Inspect4
--InterferenceMeasure /
Record
(a) Surface deformations, scratches and dents only can be blended out at a 10:1 taper ratio, and reworked.
Refer to OHM 57-52-11 (Outboard T.E. Flap) and OHM 57-52-01 (Inboard T.E. Flap) as an accepted
procedure. The minimum thickness after rework of the old configuration fitting is 0.090 inch. NOTE: Contact
Boeing if rework of the improved fitting is required.
(b) Minimum thickness of carriage attach lug is 0.14 inch.
FIGURE 2: CHECK FOR CLEARANCE / INTERFERENCE
(SHEET 2 OF 2)
Export Controlled ECCN: 9E991 - BOEING
PROPRIETARY - Copyright © Unpublished
Work - See page 1 for details.
Original Issue: February 07, 1975
727-57A0135Revision 4 September 26, 2012
33 of 37
BOEING SERVICE BULLETIN 727-57A0135
ALERTALERT

### Page 34 (OCR)

BOEING SERVICE BULLETIN 727-57A0135
ALERT  ALERT
FOREFLAP
FOREFLAP  SEQUENCING
CARRIAGE  CARRIAGE
ATTACH FITTING
SEE
MIDFLAP
• FLAP TRACK  FLAP CARRIAGE
SEQUENCING
TOGGLE  FWDY
OUTBOARD TRAILING EDGE FLAP INSTALLATION
(TYPICAL FOR INBOARD AND OUTBOARD FOREFLAP)
FOREFLAP
- CARRIAGE
ATTACH FITTING
BEARING
(2) CARRIAGE  ATTACH LUC
FWD  OOO LUG ASSEMBLY
TYPICAL  145 SHIM  V46362
FIGURE 3: REWORK OF LUG ASSEMBLY
(SHEET 1 OF 3)
Original Issue: February 07, 1975
Revision 4 September 26, 2012  Export Controlled ECCN: 9E991 - BOEING  PROPRIETARY - Copyright © Unpublished  727-57A0135
Work - See page 1 for details.  34 0f 37

### Page 35

The step numbers shown below agree with the numbers shown in the circle symbols in the figure. The QTY
numbers shown below are the numbers of parts necessary for one fitting.
NOTESQTYPART NUMBERNAMETASKSTEP
In accordance with OHM 57-52-11
(Outboard T.E. Flap) and OHM 57-
52-01 (Inboard T.E. Flap). (a)
--Lug AssemblyRemove /
Keep
1
--ShimRemove /
Keep
In accordance with SOPM 20-30-
03.
--Lug faceClean2
As necessary for a maximum
clearance of 0.003 inch. Hold a
surface finish of 125 micro inches
or better in accordance with SOPM
20-10-02 and SOPM 20-10-03. (b)
--Sand or Grind
Magnetic Particle Inspection in ac-
cordance with SOPM 20-20-01.
--Lug faceInspect
In accordance with SOPM 20-10-
03.
--Lug faceFlap Peen
To the lug face in accordance with
SOPM 20-42-10.
--Cadmium Plate,
Stylus
Apply
Magnetic Particle Inspection in ac-
cordance with SOPM 20-20-01.
--Lug faceInspect
One layer of each on the lug face
in accordance with SOPM 20-41-
02.
-BMS 10-11, Type
1
PrimerApply
-BMS 10-11, Type
2
EnamelApply
In accordance with OHM 57-52-11
(Outboard T.E. Flap) and OHM 57-
52-01 (Inboard T.E. Flap) for cor-
rect fasteners.
169-26258 (d) -or-
69-30160 (c)
Lug AssemblyPut / Hold /
Align
3
Locate to match the carriage lug.1BACS40R007U015ShimPut / Hold /
Align
4
Match holes in shim to the carriage
lug.
2Drill / Deburr
FIGURE 3: REWORK OF LUG ASSEMBLY
(SHEET 2 OF 3)
Export Controlled ECCN: 9E991 - BOEING
PROPRIETARY - Copyright © Unpublished
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Original Issue: February 07, 1975
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BOEING SERVICE BULLETIN 727-57A0135
ALERTALERT

### Page 36

NOTESQTYPART NUMBERNAMETASKSTEP
In accordance with OHM 57-52-11
(Outboard T.E. Flap) and OHM 57-
52-01 (Inboard T.E. Flap). Shim
equally both lug faces where mate-
rial was removed, if necessary.
0.003 inch maximum gap prior to
torqueing.
1-Lug AssemblyInstall / Kept5
1-ShimInstall / Kept
In accordance with OHM 57-52-11
(Outboard T.E. Flap) and OHM 57-
52-01 (Inboard T.E. Flap).
2-BoltInstall / Kept6
2-WasherInstall / Kept
2-NutInstall / Kept
(a) The Lug Assembly includes the carriage attach lug and the bearing. Do not remove the bearing. Use the
parts again if they are in an approved condition for service.
(b) Minimum lug thickness is 0.14 inch.
(c) Inboard Flap.
(d) Outboard Flap.
FIGURE 3: REWORK OF LUG ASSEMBLY
(SHEET 3 OF 3)
Export Controlled ECCN: 9E991 - BOEING
PROPRIETARY - Copyright © Unpublished
Work - See page 1 for details.
Original Issue: February 07, 1975
727-57A0135Revision 4 September 26, 2012
36 of 37
BOEING SERVICE BULLETIN 727-57A0135
ALERTALERT

### Page 37

The step numbers shown below agree with the numbers shown in the circle symbols in the figure. The QTY
numbers shown below are the numbers of parts necessary for one fitting.
NOTESQTYPART NUMBERNAMETASKSTEP
Aft outboard location for improved
fitting only. Hole is 0.250 - 0.254
inches dia. Counter Sink is 100
deg. X -.360-0.370 inch diameter..
1BACB30VF4K6BoltInstall1
For installation of all other mounting holes and fasteners refer to OHM 57-52-11 as an accepted procedure.
FIGURE 4: CARRIAGE FITTING INSTALLATION FOR OUTBOARD FORE FLAP WBL 348 - DEVIATION
FROM OVERHAUL MANUAL
(SHEET 1 OF 1)
Export Controlled ECCN: 9E991 - BOEING
PROPRIETARY - Copyright © Unpublished
Work - See page 1 for details.
Original Issue: February 07, 1975
727-57A0135Revision 4 September 26, 2012
37 of 37
BOEING SERVICE BULLETIN 727-57A0135
ALERTALERT

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