# Boeing Alert Service Bulletin 747-53A2835: Revision 1

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- Document: [Boeing Alert Service Bulletin 747-53A2835](https://openairdocs.org/service-documents/boeing/747-53a2835.md)
- Title as filed: U.S. DOT/FAA - Service Information
- Pages: 81
- PDF: https://openairdocs.org/files/sha256/09/d1/09d1efdf7bf38691404334b8bb86dc033914e087806c1441b600155bf9fc356a
- Page: https://openairdocs.org/service-documents/boeing/747-53a2835/file/09d1efdf7bf3

## Text

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### Page 1

Commercial 
Airplanes
747
Service Bulletin
ALERT
Number: 747-53A2835
Original Issue: October 28, 2010
ATA System: 5312
SUBJECT: FUSELAGE - Center Section: Station 520 To Station 2360 - Forward and Aft Lower
Lobe Cargo Door Lower Sills - Latch Pin Inspection and Replacement
Export of this technology is controlled under the United States Export Administration Regulations (EAR) (15
CFR 730-774). An export license may be required before it is used for development, production or use by foreign
persons from specific countries. The controller of this data has the individual responsibility to abide by all export
laws.
9E991ECCN:
BOEING PROPRIETARY, CONFIDENTIAL, AND/OR TRADE SECRET
Copyright © 2010 The Boeing Company
Unpublished Work - All Rights Reserved
Boeing claims copyright in each page of this document only to the extent that the page contains copyrightable
subject matter. Boeing also claims copyright in this document as a compilation and/or collective work.
This document includes proprietary information owned by The Boeing Company and/or one or more third parties.
Treatment of the document and the information it contains is governed by contract with Boeing. For more
information, contact The Boeing Company, P.O. Box 3707, Seattle, Washington 98124.
Boeing, the Boeing signature, the Boeing symbol, 707, 717, 727, 737, 747, 757, 767, 777, 787, Dreamliner,
BBJ, DC-8, DC-9, DC-10, KC-10, KDC-10, MD-10, MD-11, MD-80, MD-88, MD-90, P-8A, Poseidon and the
Boeing livery are all trademarks owned by The Boeing Company; and no trademark license is granted in
connection with this document unless provided in writing by Boeing.
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Table of Contents
Summary ...................................................... 5
1. PLANNING INFORMATION ........................................ 9
A. Effectivity ................................................ 9
1. Airplanes ............................................. 9
2. Spares Affected ........................................ 2 0
B. Concurrent Requirements ...................................... 2 0
C. Reason ................................................ 2 0
D. Description .............................................. 2 1
E. Compliance .............................................. 2 1
F. Approval ............................................... 2 5
G. Manpower .............................................. 2 6
H. Weight and Balance Changes .................................... 2 8
I. Electrical Load Data ......................................... 2 8
J. References .............................................. 2 8
1. Existing Data .......................................... 2 8
2. Data supplied with this Service Bulletin ............................ 2 8
3. Installation Drawings Used in the Preparation of this Service Bulletin ............ 2 8
K. Publications Affected ........................................ 2 9
L. Interchangeability and Intermixability of Parts ........................... 2 9
2. MATERIAL INFORMATION ........................................ 3 1
A. Material - Price and Availability ................................... 3 1
B. Industry Support Information .................................... 3 1
C. Parts Necessary For Each Airplane ................................. 3 1
1. Kits/Parts ............................................ 3 1
2. Parts and Materials Supplied by the Operator ........................ 3 1
3. Parts Modified and Reidentified ................................ 3 2
4. Parts Removed and Not Replaced .............................. 3 2
D. Parts Necessary to Change Spares ................................. 3 2
E. Special Tooling - Price and Availability ............................... 3 2
F. Special Tooling Necessary to do this Service Bulletin ....................... 3 2
3. ACCOMPLISHMENT INSTRUCTIONS .................................. 3 3
A. GENERAL INFORMATION ..................................... 3 3
B. WORK INSTRUCTIONS ....................................... 3 4
FIGURE 1: LOWER LOBE FORWARD AND AFT CARGO DOORS - LATCH PIN INSPECTIONS . . 37
FIGURE 2: LOWER LOBE FORWARD AND AFT CARGO DOORS - LATCH PIN REPLACEMENT [Group
1-2, Configuration 1; Group 3] ................................. 4 0
FIGURE 3: LOWER LOBE FORWARD AND AFT CARGO DOORS - LATCH PIN REPLACEMENT [Group
1-2, Configuration 2] ...................................... 4 5
FIGURE 4: LOWER LOBE FORWARD AND AFT CARGO DOORS - LATCH PIN REPLACEMENT [Group
1, Configuration 3] ....................................... 5 0
FIGURE 5: LOWER LOBE FORWARD AND AFT CARGO DOORS - LATCH PIN REPLACEMENT [Group
1, Configuration 4] ....................................... 5 5
FIGURE 6: LOWER LOBE FORWARD AND AFT CARGO DOORS - LATCH PIN AND BEARING PLATE
MODIFICATION OR REPLACEMENT [Group 1, Configuration 3] .............. 6 0
FIGURE 7: LOWER LOBE FORWARD AND AFT CARGO DOORS - LATCH PIN AND BEARING PLATE
MODIFICATION OR REPLACEMENT [Group 1, Configuration 4] .............. 7 1
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Commercial 
Airplanes
747
Service Bulletin
ALERT
SummaryNumber: 747-53A2835Original Issue: October 28, 2010
ATA System: 5312
SUBJECT: FUSELAGE - Center Section: Station 520 To Station 2360 - Forward and Aft Lower
Lobe Cargo Door Lower Sills - Latch Pin Inspection and Replacement
THIS BULLETIN IS SENT TO THE OPERATORS OF RECORD OF THE AIRPLANES SHOWN IN PARAGRAPH
1.A., EFFECTIVITY. IF AN AIRPLANE HAS BEEN LEASED OR SOLD, SEND THIS SERVICE BULLETIN TO
THE NEW OPERATOR. IF APPLICABLE SPARES HAVE BEEN SOLD, SEND THIS SERVICE BULLETIN TO
THE NEW OWNER.
CONCURRENT REQUIREMENTS
None.
BACKGROUND
A latch pin, from the number 8 (most aft) latch position on aft lower lobe cargo door lower sill, has fractured in
service. Investigation revealed the crack initiated by fatigue and propagated by a combination of fatigue and
stress corrosion. If the latch pins on the forward and aft cargo door lower sill are not regularly inspected and
broken latch pins are not replaced, the forward and/or aft cargo doors could open unexpectedly during service,
causing rapid decompression and possible loss of the cargo door.
One operator has reported a fractured latch pin from the lower sill of the aft lower lobe cargo door. Part of the
pin was found on the ground during an airplane walk around. The airplane had completed 75,495 flight hours
and 9,393 flight cycles. A dye penetrant inspection of the remaining seven latch pins in the aft cargo door was
done with no defects found. The number 8 latch pin was assumed to be original. The number 8 latch cam was
a reworked/overhauled part. The latch pin fracture initiated on the pin internal diameter.
This service bulletin provides inspections for broken or cracked latch pins on the forward and aft lower lobe
cargo door lower sills. Replacing broken or cracked latch pins will mitigate the possibility that a cargo door could
open unexpectedly during service.
The inspections for broken or cracked latch pins provided by this service bulletin do not replace inspections for
latch pin wear. OHM 52-34-11 and OHM 52-35-11 give wear limits for the latch pins.
Boeing Service Related Problem (SRP) 747-SRP-53-0351 is related to this service bulletin.
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ACTION (PRR 85901-105RS)
Group 1, Configuration 1-2; Group 2-3:
Open the lower lobe forward and aft cargo doors to get access to the latch pins on the lower sill. Do a general
visual inspection for broken or missing latch pins and a detailed inspection of the latch pins for cracking. For
each latch fitting location where a latch pin is broken, replace the latch pin and replace the latch pin(s) at the
adjacent latch fitting location(s). For each latch pin where any crack is found, replace the latch pin. Put the
airplane back to a serviceable condition. Repeat the inspections.
Group 1, Configuration 3-4:
Open the lower lobe forward and aft cargo doors to get access to the latch pins on the lower sill. Do a general
visual inspection for broken or missing latch pins and a detailed inspection of the latch pins for cracking. Option
1: For each latch fitting location where a latch pin is broken, replace the latch pin and replace the latch pin(s) at
the adjacent latch fitting location(s). For each latch pin where any crack is found, replace the latch pin. Option
2: Modify or replace the latch pins and modify the bearing plates at all latch fitting locations. Put the airplane
back to a serviceable condition. Repeat the inspections.
EFFECTIVITY
All 747-100, 747-100B, 747-100B SUD, 747-200B, 747-200C, 747-200F, 747-300, 747-400, 747-400D, 747-400F,
747SP, 747SR airplanes. Refer to Paragraph 1.A.1., Airplanes, for the list of affected airplanes.
COMPLIANCE
Refer to Paragraph 1.E., Compliance.
The Federal Aviation Administration (FAA) will possibly release an Airworthiness Directive related to this service
bulletin. The Airworthiness Directive will make the compliance tasks and times given in this service bulletin
mandatory.
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
Operator Supplied Parts/Materials.
Refer to Paragraph 2.A., Material - Price and Availability
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BOEING SERVICE BULLETIN 747-53A2835
ALERT  ALERT
DOORWAY LOWER SILL
NOTE:
NUMBERS ADJACENT TO
LATCH FITTINGS DENOTE  LATCH FITTING LOCATIONS  6  2 LOCATIONS
SOME STRUCTURE
NOT SHOWN FOR CLARITY
INSPECT FOR BROKEN OR
CRACKED LATCH PIN.
IF LATCH PIN IS CRACKED,
REPLACE THE LATCH PIN.
IF LATCH PIN IS BROKEN OR
MISSING, REPLACE THE LATCH
PIN AND REPLACE THE LATCH
PIN(S) AT ADJACENT LATCH
16 LOCATIONS TOTAL  TYPICAL  FITTING LOCATION(S)
ODD NUMBERED LATCH FITTING LOCATION SHOWN,
EVEN NUMBERED LATCH FITTING LOCATION OPPOSITE
B  1981402
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Commercial 
Airplanes
747
Service Bulletin
ALERT
Number: 747-53A2835
Original Issue: October 28, 2010
ATA System: 5312
SUBJECT: FUSELAGE - Center Section: Station 520 To Station 2360 - Forward and Aft Lower
Lobe Cargo Door Lower Sills - Latch Pin Inspection and Replacement
THIS BULLETIN IS SENT TO THE OPERATORS OF RECORD OF THE AIRPLANES SHOWN IN PARAGRAPH
1.A., EFFECTIVITY. IF AN AIRPLANE HAS BEEN LEASED OR SOLD, SEND THIS SERVICE BULLETIN TO
THE NEW OPERATOR. IF APPLICABLE SPARES HAVE BEEN SOLD, SEND THIS SERVICE BULLETIN TO
THE NEW OWNER.
1.    PLANNING INFORMATION
A. Effectivity
1. Airplanes
Refer to Service Bulletin Index Document D6-30300 Part 3 for Airplane Variable Number, Line
Number, and Serial Number data.
This service bulletin is for the airplanes shown below. An equivalent change is on subsequent
production airplanes. Refer to PRR 85901-105RS for data about this change.
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DESCRIPTIONCONFIGURATIONGROUP
747 airplanes line numbers 1 through 263 and 265.-1
Airplanes that have modified or replaced latch pins and latch fitting
bearing plates in accordance with Boeing Service Bulletin
747-52-2105 Original Issue, Revision 1 or Revision 2 on the lower
lobe forward and aft cargo doors, or in accordance with Figure 6 or
Figure 7 of this service bulletin, AND have done Boeing Service
Bulletin 747-52-2260 Original Issue or Revision 1.
1
Airplanes that have modified or replaced latch pins and latch fitting
bearing plates in accordance with Boeing Service Bulletin
747-52-2105 Original Issue, Revision 1 or Revision 2 on the lower
lobe forward and aft cargo doors, or in accordance with Figure 6 or
Figure 7 of this service bulletin, AND have not done Boeing Service
Bulletin 747-52-2260 Original Issue or Revision 1.
2
Airplanes that have not modified or replaced latch pins and latch
fitting bearing plates in accordance with Boeing Service Bulletin
747-52-2105 Original Issue, Revision 1 or Revision 2 on the lower
lobe forward and aft cargo doors, or in accordance with Figure 6 or
Figure 7 of this service bulletin, AND have done Boeing Service
Bulletin 747-52-2260 Original Issue or Revision 1.
3
Airplanes that have not modified or replaced latch pins and latch
fitting bearing plates in accordance with Boeing Service Bulletin
747-52-2105 Original Issue, Revision 1 or Revision 2 on the lower
lobe forward and aft cargo doors, or in accordance with Figure 6 or
Figure 7 of this service bulletin, AND have not done Boeing Service
Bulletin 747-52-2260 Original Issue or Revision 1.
4
747 airplanes line numbers 264 and 266 through 1078.-2
Airplanes that have accomplished Boeing Service Bulletin
747-52-2260 Original Issue or Revision 1.
1
Airplanes that have not accomplished Boeing Service Bulletin
747-52-2260 Original Issue or Revision 1.
2
747 airplanes line numbers 1079 through 1419.-3
Airplane Models:
747-100, 747-100B, 747-100B SUD, 747-200B, 747-200C, 747-200F, 747-300, 747-400,
747-400D, 747-400F, 747SP, 747SR
GroupVariable Number
1RA001 - RA034
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GroupVariable Number
1RA101 - RA115
1RA161 - RA164
1RA201 - RA203
1RA216 - RA217
1RA245 - RA246
1RA251 - RA265
2RA266
1RA301 - RA317
2RA318
1RA351 - RA360
1RA369 - RA373
1RA401 - RA418
1RA501 - RA502
1RA521 - RA528
1RA532 - RA543
2RA544 - RA548
1RA551 - RA552
1RA559 - RA561
1RA581 - RA582
1RA585
1RA601 - RA602
1RA631 - RA635
1RA651 - RA652
1RA671 - RA677
1RA701 - RA702
1RA721 - RA724
2RA725 - RA731
1RA741 - RA745
1RA749
2RA750
1RA761 - RA762
1RA781 - RA783
2RA784
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GroupVariable Number
1RA901 - RA916
1RB001 - RB010
2RB011 - RB012
1RB013 - RB016
1RB041 - RB044
1RB071 - RB075
1RB101 - RB102
2RB411 - RB413
2RB421
1RB601 - RB607
2RB681 - RB697
2RB711
2RB721 - RB723
2RB741 - RB748
1RD001 - RD004
1RD021 - RD022
1RD041 - RD044
2RD045 - RD059
1RD071 - RD072
2RD081 - RD083
2RD091 - RD092
1RD101 - RD104
2RD121 - RD127
2RD131 - RD144
2RD166 - RD167
2RD171 - RD172
2RD181 - RD183
2RD201 - RD204
2RD221 - RD227
2RD231 - RD235
2RD241 - RD243
2RD251 - RD262
2RD271 - RD272
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GroupVariable Number
2RD291 - RD292
2RD301 - RD302
2RD311
2RD351 - RD358
2RD361 - RD366
2RD381 - RD383
2RD411 - RD414
2RD421 - RD426
2RD431 - RD435
2RD441 - RD442
2RD451 - RD456
2RD461
2RD471 - RD475
2RD513 - RD519
2RD531 - RD533
2RD551
2RD561
2RD571
2RD581 - RD583
2RD591 - RD593
2RD601 - RD607
1RD621 - RD622
2RD623
2RD641 - RD649
2RD651 - RD659
2RD661
2RD671
2RD681 - RD682
2RD691 - RD692
2RD701 - RD702
2RD721 - RD722
2RD741 - RD742
2RD751 - RD755
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GroupVariable Number
2RD761
2RD771 - RD775
2RD781 - RD783
2RD791 - RD792
2RE001
3RF001 - RF006
1RG001
2RG002 - RG009
2RG091
2RG095
2RG101 - RG104
2RG121 - RG126
2RG141 - RG142
2RG161 - RG164
2RG171 - RG174
2RG191 - RG193
2RG211 - RG213
2RG221 - RG222
2RH101 - RH102
2RH111 - RH112
2RH121 - RH122
1RJ131 - RJ133
2RJ151 - RJ152
2RJ301 - RJ303
2RJ321 - RJ322
2RJ331 - RJ333
3RL401 - RL403
3RL411 - RL436
3RL451 - RL456
3RL461 - RL462
3RL471 - RL481
3RL491 - RL492
3RL501 - RL502
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GroupVariable Number
3RL511 - RL516
3RL521 - RL522
3RL531 - RL534
3RL551
3RL561 - RL568
3RL571 - RL572
3RL576 - RL577
3RL579
3RL581 - RL586
3RL651 - RL655
3RL671 - RL675
3RL681 - RL684
3RL751 - RL752
3RM001 - RM007
3RM010 - RM013
3RM021 - RM024
3RM026 - RM030
3RM036 - RM045
3RM051 - RM053
3RM071
3RM081 - RM084
3RM091
3RM096 - RM097
3RM116 - RM117
3RM126 - RM132
3RM136 - RM147
3RM156 - RM158
3RM166 - RM177
3RM191 - RM192
3RM231 - RM233
3RM241 - RM246
3RM261 - RM264
3RM316 - RM318
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GroupVariable Number
3RM331 - RM333
3RM341
3RM351 - RM355
3RM366 - RM367
3RM401 - RM403
3RM426
3RM431
3RM441 - RM443
3RM445
3RM801 - RM803
3RM811 - RM813
3RM851 - RM859
3RM861 - RM863
3RM871 - RM899
3RM901 - RM906
3RM911
2RR001 - RR005
2RR021 - RR025
2RR031
1RR201
2RR202 - RR206
1RR221
2RR222 - RR226
1RR261
2RR262 - RR267
1RR301
2RR302 - RR310
2RR331 - RR332
2RR336
1RR341 - RR342
2RR343 - RR345
2RR361 - RR362
2RR421 - RR422
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GroupVariable Number
2RR431 - RR432
2RR441 - RR442
2RR451
2RR501 - RR504
2RR521 - RR522
2RR526
2RR531
2RR551 - RR556
2RR561
2RR566
2RR701
2RR721 - RR722
3RR723 - RR724
2RR746 - RR747
3RR748
2RR851 - RR854
3RR855 - RR856
3RR861 - RR862
2RR951 - RR952
2RS001 - RS002
2RS201
2RS211 - RS212
2RS221 - RS222
2RS231 - RS241
2RS251 - RS259
2RS263
2RS265 - RS268
2RS271 - RS276
2RS291 - RS292
2RS301 - RS306
2RS311 - RS320
2RS331 - RS333
2RS341 - RS342
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GroupVariable Number
2RS699
2RS701 - RS703
2RS711 - RS713
2RS721 - RS722
2RS731 - RS732
2RS741 - RS743
2RS751 - RS752
2RS761 - RS762
2RS771
2RS781 - RS782
2RS786
2RT001 - RT011
3RT012 - RT014
2RT021 - RT022
2RT031 - RT033
3RT034 - RT035
2RT041 - RT047
2RT061
2RT071 - RT075
2RT101 - RT103
2RT121
2RT131 - RT134
3RT135 - RT137
2RT151 - RT152
2RT161 - RT168
2RT401 - RT412
2RT431 - RT441
3RT442 - RT447
2RT451 - RT469
2RT471 - RT499
2RT501 - RT535
2RT551 - RT568
2RT571 - RT588
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GroupVariable Number
3RT589 - RT590
2RT591
2RT601 - RT622
3RT623 - RT630
2RT631 - RT636
3RT637 - RT640
2RT641 - RT657
2RT671 - RT673
2RT681 - RT682
2RT691 - RT699
2RT701 - RT704
2RT711 - RT717
2RT741 - RT755
3RT756 - RT757
2RT776 - RT777
2RT781 - RT784
3RT801 - RT803
3RT811 - RT814
2RT831 - RT833
3RT834 - RT837
2RT861 - RT864
2RT876 - RT880
2RT931 - RT932
2RT945 - RT946
3RT947 - RT949
2RT951 - RT954
3RT955
2RT966 - RT967
2RU001 - RU004
3RU005 - RU006
3RU016 - RU017
2RU031 - RU032
2RU051 - RU052
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GroupVariable Number
2RU059 - RU062
2RU081 - RU083
3RU101 - RU102
2RU121 - RU124
3RU125 - RU132
2RU801 - RU809
2RU831 - RU841
2. Spares Affected
Examine your spares supply for the parts or components identified in Paragraph 2.C., Parts
Necessary for Each Airplane. If any parts or components are found, refer to Paragraph 2.C. for
the recommended use.
B. Concurrent Requirements
None.
C. Reason
A latch pin, from the number 8 (most aft) latch position on aft lower lobe cargo door lower sill, has
fractured in service. Investigation revealed the crack initiated by fatigue and propagated by a combination
of fatigue and stress corrosion. If the latch pins on the forward and aft cargo door lower sill are not
regularly inspected and broken latch pins are not replaced, the forward and/or aft cargo doors could
open unexpectedly during service, causing rapid decompression and possible loss of the cargo door.
One operator has reported a fractured latch pin from the lower sill of the aft lower lobe cargo door. Part
of the pin was found on the ground during an airplane walk around. The airplane had completed 75,495
flight hours and 9,393 flight cycles. A dye penetrant inspection of the remaining seven latch pins in the
aft cargo door was done with no defects found. The number 8 latch pin was assumed to be original.
The number 8 latch cam was a reworked/overhauled part. The latch pin fracture initiated on the pin
internal diameter.
This service bulletin provides inspections for broken or cracked latch pins on the forward and aft lower
lobe cargo door lower sills. Replacing broken or cracked latch pins will mitigate the possibility that a
cargo door could open unexpectedly during service.
The inspections for broken or cracked latch pins provided by this service bulletin do not replace
inspections for latch pin wear. OHM 52-34-11 and OHM 52-35-11 give wear limits for the latch pins.
Boeing Service Related Problem (SRP) 747-SRP-53-0351 is related to this service bulletin.
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D. Description
Group 1, Configuration 1-2; Group 2-3:
Open the lower lobe forward and aft cargo doors to get access to the latch pins on the lower sill. Do a
general visual inspection for broken or missing latch pins and a detailed inspection of the latch pins for
cracking. For each latch fitting location where a latch pin is broken or missing, replace the latch pin
and replace the latch pin(s) at the adjacent latch fitting location(s). For each latch pin where any crack
is found, replace the latch pin. Put the airplane back to a serviceable condition. Repeat the inspections.
Group 1, Configuration 3-4:
Open the lower lobe forward and aft cargo doors to get access to the latch pins on the lower sill. Do a
general visual inspection for broken or missing latch pins and a detailed inspection of the latch pins for
cracking. Option 1: For each latch fitting location where a latch pin is broken or missing, replace the
latch pin and replace the latch pin(s) at the adjacent latch fitting location(s). For each latch pin where
any crack is found, replace the latch pin. Option 2: Modify or replace the latch pins and modify the
bearing plates at all latch fitting locations. Put the airplane back to a serviceable condition. Repeat the
inspections.
The work in this service bulletin is done in the maintenance zone(s) given below.
Group 1:
Affected Maintenance Zones
ZoneModel
122, 142747-100, 747-200B, 747-200C,
747-200F, 747SP, 747SR
Group 2:
Affected Maintenance Zones
ZoneModel
122, 142747-100, 747-100B, 747-100B
SUD, 747-200B, 747-200C,
747-200F, 747-300, 747-400,
747-400D, 747-400F, 747SP,
747SR
Group 3:
Affected Maintenance Zones
ZoneModel
122, 142747-400, 747-400F
E. Compliance
The Federal Aviation Administration (FAA) will possibly release an Airworthiness Directive related to
this service bulletin. The Airworthiness Directive will make the compliance tasks and times given in this
service bulletin mandatory.
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Group 1-2, Configuration 1; Group 3:
Table 1: Forward and Aft Lower Lobe Cargo Door - Latch Pin Inspection and Replacement
Repeat Interval
(Not to Exceed)
Compliance Time
(Whichever Occurs Later)
ActionCondition
-Within 1,000
flight cycles af-
ter the original
issue date of
this service
bulletin
Before 6,000
total flight cy-
cles
Do a general visual inspection
for broken or missing latch pins
and a detailed inspection of the
latch pins for cracking in accor-
dance with Paragraph 3.B.,
Work Instructions, Step 2.
All airplanes
-Before further flight.Replace each broken or missing
latch pin and replace the latch
pin(s) adjacent to each broken
or missing latch pin in accor-
dance with Paragraph 3.B.,
Work Instructions, Step 2.a.
If a latch pin is broken
into two or more pieces
-Before further flightReplace each cracked latch pin
in accordance with Paragraph
3.B., Work Instructions, Step
2.b.
If any crack is found in
a latch pin
1,600 flight cycles
(a)
Within 6,000 flight cycles after
replacement of latch pins.
For each door:
Repeat the general visual in-
spection for broken or missing
latch pins and the detailed in-
spection of the latch pins for
cracking in accordance with
Paragraph 3.B., Work Instruc-
tions, Step 2.
Doors with all latch pins
replaced with new latch
pins at all latch fitting
locations and at the
same maintenance visit
in accordance with this
service bulletin.
1,600 flight cycles
(a)
Within 1,600 flight cycles after
the previous inspection of all
latch pins.
For each door:
Repeat the general visual in-
spection for broken or missing
latch pins and the detailed in-
spection of the latch pins for
cracking in accordance with
Paragraph 3.B., Work Instruc-
tions, Step 2.
Doors without all latch
pins replaced with new
latch pins at all latch fit-
ting locations and at the
same maintenance visit
in accordance with this
service bulletin.
(a) Replacement of a latch pin is not terminating action for the inspections of that latch pin.
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Group 1-2, Configuration 2:
Table 2: Forward and Aft Lower Lobe Cargo Door - Latch Pin Inspection and Replacement
Repeat Interval
(Not to Exceed)
Compliance Time
(Whichever Occurs Later)
ActionCondition
-Within 1,000
flight cycles af-
ter the original
issue date of
this service
bulletin
Before 6,000
total flight cy-
cles
Do a general visual inspection
for broken or missing latch pins
and a detailed inspection of the
latch pins for cracking in accor-
dance with Paragraph 3.B.,
Work Instructions, Step 3.
All airplanes
-Before further flight.Replace each broken or missing
latch pin and replace the latch
pin(s) adjacent to each broken
or missing latch pin in accor-
dance with Paragraph 3.B.,
Work Instructions, Step 3.a.
If a latch pin is broken
into two or more pieces
-Before further flightReplace each cracked latch pin
in accordance with Paragraph
3.B., Work Instructions, Step
3.b.
If any crack is found in
a latch pin
1,600 flight cycles
(a)
Within 6,000 flight cycles after
replacement of latch pins.
For each door:
Repeat the general visual in-
spection for broken or missing
latch pins and the detailed in-
spection of the latch pins for
cracking in accordance with
Paragraph 3.B., Work Instruc-
tions, Step 3.
Doors with all latch pins
replaced with new latch
pins at all latch fitting
locations and at the
same maintenance visit
in accordance with this
service bulletin.
1,600 flight cycles
(a)
Within 1,600 flight cycles after
the previous inspection of all
latch pins.
For each door:
Repeat the general visual in-
spection for broken or missing
latch pins and the detailed in-
spection of the latch pins for
cracking in accordance with
Paragraph 3.B., Work Instruc-
tions, Step 3.
Doors without all latch
pins replaced with new
latch pins at all latch fit-
ting locations and at the
same maintenance visit
in accordance with this
service bulletin.
(a) Replacement of a latch pin is not terminating action for the inspections of that latch pin.
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Group 1, Configuration 3:
Table 3: Forward and Aft Lower Lobe Cargo Door - Latch Pin Inspection and Replacement
Repeat Interval
(Not to Exceed)
Compliance Time
(Whichever Occurs Later)
ActionCondition
-Within 1,000
flight cycles af-
ter the original
issue date of
this service
bulletin
Before 6,000
total flight cy-
cles
Do a general visual inspection
for broken or missing latch pins
and a detailed inspection of the
latch pins for cracking in accor-
dance with Paragraph 3.B.,
Work Instructions, Step 4.
All airplanes
-Before further flight.Replace each broken or missing
latch pin and replace the latch
pin(s) adjacent to each broken
or missing latch pin in accor-
dance with Paragraph 3.B.,
Work Instructions, Step 4.a.
OPTION 1 or OPTION 2.
If a latch pin is broken
into two or more pieces
-Before further flightReplace each cracked latch pin
in accordance with Paragraph
3.B., Work Instructions, Step
4.a. OPTION 1 or OPTION 2.
If any crack is found in
a latch pin
1,600 flight cycles
(a)
Within 6,000 flight cycles after
replacement of latch pins.
For each door:
Repeat the general visual in-
spection for broken or missing
latch pins and the detailed in-
spection of the latch pins for
cracking in accordance with
Paragraph 3.B., Work Instruc-
tions, Step 4.
Doors with all latch pins
replaced with new latch
pins at all latch fitting
locations and at the
same maintenance visit
in accordance with this
service bulletin.
1,600 flight cycles
(a)
Within 1,600 flight cycles after
the previous inspection of all
latch pins.
For each door:
Repeat the general visual in-
spection for broken or missing
latch pins and the detailed in-
spection of the latch pins for
cracking in accordance with
Paragraph 3.B., Work Instruc-
tions, Step 4.
Doors without all latch
pins replaced with new
latch pins at all latch fit-
ting locations and at the
same maintenance visit
in accordance with this
service bulletin.
(a) Replacement of a latch pin is not terminating action for the inspections of that latch pin.
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Group 1, Configuration 4:
Table 4: Forward and Aft Lower Lobe Cargo Door - Latch Pin Inspection and Replacement
Repeat Interval
(Not to Exceed)
Compliance Time
(Whichever Occurs Later)
ActionCondition
-Within 1,000
flight cycles af-
ter the original
issue date of
this service
bulletin
Before 6,000
total flight cy-
cles
Do a general visual inspection
for broken or missing latch pins
and a detailed inspection of the
latch pins for cracking in accor-
dance with Paragraph 3.B.,
Work Instructions, Step 5.
All airplanes
-Before further flight.Replace each broken or missing
latch pin and replace the latch
pin(s) adjacent to each broken
or missing latch pin in accor-
dance with Paragraph 3.B.,
Work Instructions, Step 5.a.
OPTION 1 or OPTION 2.
If a latch pin is broken
into two or more pieces
-Before further flightReplace each cracked latch pin
in accordance with Paragraph
3.B., Work Instructions, Step
5.a. OPTION 1 or OPTION 2.
If any crack is found in
a latch pin
1,600 flight cycles
(a)
Within 6,000 flight cycles after
replacement of latch pins.
For each door:
Repeat the general visual in-
spection for broken or missing
latch pins and the detailed in-
spection of the latch pins for
cracking in accordance with
Paragraph 3.B., Work Instruc-
tions, Step 5.
Doors with all latch pins
replaced with new latch
pins at all latch fitting
locations and at the
same maintenance visit
in accordance with this
service bulletin.
1,600 flight cycles
(a)
Within 1,600 flight cycles after
the previous inspection of all
latch pins.
For each door:
Repeat the general visual in-
spection for broken or missing
latch pins and the detailed in-
spection of the latch pins for
cracking in accordance with
Paragraph 3.B., Work Instruc-
tions, Step 5.
Doors without all latch
pins replaced with new
latch pins at all latch fit-
ting locations and at the
same maintenance visit
in accordance with this
service bulletin.
(a) Replacement of a latch pin is not terminating action for the inspections of that latch pin.
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.
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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 inspection 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.
Group 1-2, Configuration 1; Group 3:
Elapsed HoursTask HoursNumber of PersonsTask
0.250.251Open Access
1.001.001FIGURE 1
4.008.002FIGURE 2 (a)
0.250.251Close Access
5.509.50TOTAL FOR EACH AIRPLANE (a)
(a) This estimate includes replacement of all 16 latch pins. It may not be necessary
to replace all 16 latch pins.
Group 1-2, Configuration 2:
Elapsed HoursTask HoursNumber of PersonsTask
0.250.251Open Access
1.001.001FIGURE 1
4.008.002FIGURE 3 (a)
0.250.251Close Access
5.509.50TOTAL FOR EACH AIRPLANE (a)
(a) This estimate includes replacement of all 16 latch pins. It may not be necessary
to replace all 16 latch pins.
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Group 1, Configuration 3:
OPTION 1: DO NOT MODIFY THE LATCH FITTINGS
Elapsed HoursTask HoursNumber of PersonsTask
0.250.251Open Access
1.001.001FIGURE 1
4.008.002FIGURE 4 (a)
0.250.251Close Access
5.509.50TOTAL FOR EACH AIRPLANE (a)
(a) This estimate includes replacement of all 16 latch pins. It may not be necessary
to replace all 16 latch pins.
Group 1, Configuration 3:
OPTION 2: MODIFY THE LATCH FITTINGS
Elapsed HoursTask HoursNumber of PersonsTask
0.250.251Open Access
1.001.001FIGURE 1
18.0036.002FIGURE 6 (a)
0.250.251Close Access
19.5037.50TOTAL FOR EACH AIRPLANE (a)
(a) This estimate includes modification of all latch pins and latch fitting bearing
plates. It is acceptable to replace latch pins and bearing plates with new parts.
Group 1, Configuration 4:
OPTION 1: DO NOT MODIFY THE LATCH FITTINGS
Elapsed HoursTask HoursNumber of PersonsTask
0.250.251Open Access
1.001.001FIGURE 1
4.008.002FIGURE 5 (a)
0.250.251Close Access
5.509.50TOTAL FOR EACH AIRPLANE (a)
(a) This estimate includes replacement of all 16 latch pins. It may not be necessary
to replace all 16 latch pins.
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Group 1, Configuration 4:
OPTION 2: MODIFY THE LATCH FITTINGS
Elapsed HoursTask HoursNumber of PersonsTask
0.250.251Open Access
1.001.001FIGURE 1
18.0036.002FIGURE 7 (a)
0.250.251Close Access
19.5037.50TOTAL FOR EACH AIRPLANE (a)
(a) This estimate includes modification of all latch pins and latch fitting bearing
plates. It is acceptable to replace latch pins and bearing plates with new parts.
H. Weight and Balance Changes
None.
I. Electrical Load Data
Not changed.
J. References
1. Existing Data
a. Engineering Change Memo PRR 85901-105RS
b. Service Related Problem (SRP) 747-SRP-53-0351
c. Boeing Service Bulletin 747-52-2105 and 747-52-2260
d. Overhaul Manual (OHM) 52-34-11, 52-35-11
e. Standard Overhaul Practices Manual (SOPM) 20-10-02, 20-10-03, 20-20-01, 20-30-02,
20-42-03, 20-42-05, 20-50-08, 20-50-10, 20-50-19
f. 747 Maintenance Planning Document (MPD)
2. Data supplied with this Service Bulletin
None.
3. Installation Drawings Used in the Preparation of this Service Bulletin
TitleDrawing Number
SILL INSTL - LOWER MAIN, FWD CARGO DOOR65B04216
SILL INSTALLATION - LOWER MAIN, AFT CARGO DOOR65B04642
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These drawings were used to prepare this service bulletin. These drawings are not necessary to
make the specified changes, and are not supplied with this service bulletin. These drawings may
not be applicable to all airplane configurations or operators.
K. Publications Affected
1. Publications:
None.
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. 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.
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### Page 31

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. 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
None.
2. Parts and Materials Supplied by the Operator
Group 1, Configuration 1-2; Group 2-3:
NotesExisting Part
Number
NameQTYPart Number / Specification
(a) (b)69B02005-4 ORPIN, LATCH1669B02005-6 (69B02005-4 or
65B02005-5 optional) 69B02005-5 OR
69B02005-6
(c)-PRESSURE AND ENVIRON-
MENTAL SEALANT-CHRO-
MATE TYPE
8 OzBMS5-95 TYPE 1, CLASS B
(a) One new latch pin is required for each latch pin location where the existing latch pin is broken or
missing. There are 16 latch pins on each airplane.
(b) Discard existing latch pins that are broken or cracked and discard existing latch pins adjacent to
broken latch pins.
(c) See the Qualified Products List at the end of the Boeing Material Specification (BMS) for supplier
data.
Group 1, Configuration 3-4:
NotesExisting Part
Number
NameQTYPart Number / Specification
(a)65B04299-1 OR
65B04299-5
BEARING PLATE865B04299-15 (65B04299-7 or
65B04299-13 optional)
(a)65B04299-2 OR
65B04299-6
BEARING PLATE865B04299-16 (65B04299-8 or
65B04299-14 optional)
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Group 1, Configuration 3-4:
NotesExisting Part
Number
NameQTYPart Number / Specification
(b) (c) (d)69B02005-3LATCH PIN1669B02005-6 (69B02005-3,
69B02005-4 or 65B02005-5 op-
tional)
(e)-SOLID FILM LUBRICANT,
LIQUID DISPERSED
8 OzBMS3-8 TYPE I
(e)-PRESSURE AND ENVIRON-
MENTAL SEALANT-CHRO-
MATE TYPE
8 OzBMS5-95 TYPE 1, CLASS B
(e)-PRESSURE AND ENVIRON-
MENTAL SEALANT-CHRO-
MATE TYPE
8 OzBMS5-95 TYPE 1, CLASS C
(a) New bearing plates are required if Option 2, 'Modify the latch fittings', is selected. Alternatively, the
existing bearing plates can be modified.
(b) One new latch pin is required for each latch pin location where the existing latch pin is broken or
missing. There are 16 latch pins on each airplane.
(c) Discard existing latch pins that are broken or cracked and discard existing latch pins adjacent to
broken latch pins.
(d) If a 69B02005-3 latch pin is removed, it is necessary to rework the latch fitting before installing a
69B02005-4, 69B02005-5 or 69B02005-6 latch pin.
(e) See the Qualified Products List at the end of the Boeing Material Specification (BMS) for supplier
data.
3. Parts Modified and Reidentified
None.
4. Parts Removed and Not Replaced
None.
D. Parts Necessary to Change Spares
None.
E. Special Tooling - Price and Availability
None.
F. Special Tooling Necessary to do this Service Bulletin
No special tools or equipment are necessary to do the change in this service bulletin. But, maintenance
and overhaul tools in the manuals given in Paragraph 1.J., References, can be necessary. Examine
operator tool supply to make sure all necessary tools are available.
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3.    ACCOMPLISHMENT INSTRUCTIONS
A. GENERAL INFORMATION
CAUTION: KEEP THE WORK AREA, WIRES AND ELECTRICAL BUNDLES CLEAN OF METAL
PARTICLES OR CONTAMINATION WHEN YOU USE TOOLS. UNWANTED MATERIAL,
METAL PARTICLES OR CONTAMINATION CAUGHT IN WIRE BUNDLES CAN CAUSE
DAMAGE TO THE BUNDLES. DAMAGED WIRE BUNDLES CAN CAUSE SPARKS OR
OTHER ELECTRICAL DAMAGE.
NOTE: 1. The instructions identified in Paragraph 3.B., Work Instructions, and the Figure(s)
give the recommended sequence of steps. The sequence of steps to do this service
bulletin can be changed.
2. Manual titles are referred to by acronyms. Refer to Paragraph 1.J., References, for
definition of the acronyms.
3. Obey all of the warnings and cautions given in the specified manual sections.
4. Unless shown differently, these dimensions and tolerances are used:
– Linear dimensions are in inches
– Tolerance on linear dimensions, other than rivet and bolt edge margins, is plus
or minus 0.03 inch
– Tolerance on rivet and bolt edge margin is plus or minus 0.05 inch
– Angular tolerance is plus or minus 2 degrees
– Torque limits to tighten nuts and bolts are in 747 SRM 51.
5. Use the approved fastener and process material substitutions in accordance with
747 SRM 51. Alternate fasteners are listed in 747 SRM 51 and Boeing Drawing
012W6100.
6. If the length of any fastener specified in this service bulletin does not meet the
installation standards in 747 SRM 51, then a fastener of the same specification, or
an approved substitute, with a length which meets the installation standards in 747
SRM 51 may be used.
7. 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 access procedures may be required.
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8. 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.
9. 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.
10. 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.
The removed part can be discarded if a new or serviceable part is installed.
B. WORK INSTRUCTIONS
1. Open the lower lobe forward and aft cargo doors to get access to the latch pins on the lower sill.
2. Group 1-2, Configuration 1; Group 3:
Do a general visual inspection for broken or missing latch pins and a detailed inspection of the
latch pins for cracking in accordance with FIGURE 1.
NOTE: It is optional to replace all latch pins with new latch pins at all latch fitting locations in
accordance with FIGURE 2. Refer to Paragraph 1.E., Compliance.
a. If a latch pin is broken into two or more pieces or is missing, replace the latch pin and replace
the latch pin(s) at the adjacent latch fitting location(s) in accordance with FIGURE 2.
b. If any crack is found in a latch pin, replace the cracked latch pin in accordance with FIGURE
2.
c. Repeat the inspections at the time given in Paragraph 1.E., Compliance.
NOTE: The inspections for broken or cracked latch pins provided by this service bulletin do
not replace inspections for latch pin wear. OHM 52-34-11 and OHM 52-35-11 give
wear limits for the latch pins.
3. Group 1-2, Configuration 2:
Do a general visual inspection for broken latch pins and a detailed inspection of the latch pins for
cracking in accordance with FIGURE 1.
NOTE: It is optional to replace all latch pins with new latch pins at all latch fitting locations in
accordance with FIGURE 3. Refer to Paragraph 1.E., Compliance.
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a. If a latch pin is broken into two or more pieces or is missing, replace the latch pin and replace
the latch pin(s) at the adjacent latch fitting location(s) in accordance with FIGURE 3.
b. If any crack is found in a latch pin, replace the cracked latch pin in accordance with FIGURE
3.
c. Repeat the inspections at the time given in Paragraph 1.E., Compliance.
NOTE: The inspections for broken or cracked latch pins provided by this service bulletin do
not replace inspections for latch pin wear. OHM 52-34-11 and OHM 52-35-11 give
wear limits for the latch pins.
4. Group 1, Configuration 3:
Do a general visual inspection for broken or missing latch pins and a detailed inspection of the
latch pins for cracking in accordance with FIGURE 1.
NOTE: It is optional to replace all latch pins with new latch pins at all latch fitting locations in
accordance with FIGURE 4 or FIGURE 6. Refer to Paragraph 1.E., Compliance.
a. If a latch pin is broken or missing or if any crack is found in a latch pin, do one of the following:
(1) OPTION 1 - DO NOT MODIFY THE LATCH FITTINGS
NOTE: This option requires that 69B02005-3 latch pins are installed. 69B02005-3 latch
pins are not available from Boeing Spares.
(a) If a latch pin is broken into two or more pieces or is missing, replace the latch pin
and replace the latch pin(s) at the adjacent latch fitting location(s) in accordance with
FIGURE 4.
(b) If any crack is found in a latch pin, replace the cracked latch pin in accordance with
FIGURE 4.
(2) OPTION 2 - MODIFY THE LATCH FITTINGS
NOTE: Accomplishment of this option will change the configuration of the airplane. Refer
to Paragraph 1.A., Effectivity.
(a) Modify or replace the latch pins and bearing plates at all latch fitting locations in
accordance with FIGURE 6.
1) If a latch pin is broken into two or more pieces or is missing, replace the latch
pin and replace the latch pin(s) at the adjacent latch fitting location(s). Do not
modify these latch pins.
2) If any crack is found in a latch pin, replace the cracked latch pin. Do not modify
the latch pin.
b. Repeat the inspections at the time given in Paragraph 1.E., Compliance.
BOEING PROPRIETARY -
Copyright © Unpublished Work - See page 1 for details.
Original Issue: October 28, 2010
747-53A2835
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BOEING SERVICE BULLETIN 747-53A2835
ALERTALERT

### Page 36

NOTE: The inspections for broken or cracked latch pins provided by this service bulletin do
not replace inspections for latch pin wear. OHM 52-34-11 and OHM 52-35-11 give
wear limits for the latch pins.
5. Group 1, Configuration 4:
Do a general visual inspection for broken or missing latch pins and a detailed inspection of the
latch pins for cracking in accordance with FIGURE 1.
NOTE: It is optional to replace all latch pins with new latch pins at all latch fitting locations in
accordance with FIGURE 5 or FIGURE 7. Refer to Paragraph 1.E., Compliance.
a. If a latch pin is broken or missing or if any crack is found in a latch pin, do one of the following:
(1) OPTION 1 - DO NOT MODIFY THE LATCH FITTINGS
NOTE: This option requires that 69B02005-3 latch pins are installed. 69B02005-3 latch
pins are not available from Boeing Spares.
(a) If a latch pin is broken into two or more pieces or is missing, replace the latch pin
and replace the latch pin(s) at the adjacent latch fitting location(s) in accordance with
FIGURE 5.
(b) If any crack is found in a latch pin, replace the cracked latch pin in accordance with
FIGURE 5.
(2) OPTION 2 - MODIFY THE LATCH FITTINGS
NOTE: Accomplishment of this option will change the configuration of the airplane. Refer
to Paragraph 1.A., Effectivity.
(a) Modify or replace the latch pins and modify the bearing plates at all latch fitting
locations in accordance with FIGURE 7.
1) If a latch pin is broken into two or more pieces or is missing, replace the latch
pin and replace the latch pin(s) at the adjacent latch fitting location(s). Do not
modify these latch pins.
2) If any crack is found in a latch pin, replace the cracked latch pin. Do not modify
the latch pin.
b. Repeat the inspections at the time given in Paragraph 1.E., Compliance.
NOTE: The inspections for broken or cracked latch pins provided by this service bulletin do
not replace inspections for latch pin wear. OHM 52-34-11 and OHM 52-35-11 give
wear limits for the latch pins.
6. Put the airplane back to a serviceable condition.
BOEING PROPRIETARY -
Copyright © Unpublished Work - See page 1 for details.
Original Issue: October 28, 2010
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BOEING SERVICE BULLETIN 747-53A2835
ALERTALERT

### Page 37 (OCR)

BOEING SERVICE BULLETIN 747-53A2835
ALERT  ALERT
NOTE:
NUMBERS ADJACENT TO
LATCH FITTINGS DENOTE
LATCH FITTING LOCATIONS
DOORWAY LOWER SILL
2 LOCATIONS
SOME STRUCTURE NOT SHOWN FOR CLARITY
1980850
FIGURE 1: LOWER LOBE FORWARD AND AFT CARGO DOORS - LATCH PININSPECTIONS
(SHEET 1 OF 3)
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### Page 38 (OCR)

BOEING SERVICE BULLETIN 747-53A2835
ALERT  ALERT
BEARING PLATE
TYPICAL
PRACI
LOCATIONS
TYPICAL
LATCH FITTING LOCATIONS
1, 3, 5 AND 7
BEARING PLATE
TYPICAL
CRACK
LOCATIONS
TYPICAL
I LATCH FITTING LOCATIONS
2,4,6 AND 8
1980876
FIGURE 1: LOWER LOBE FORWARD AND AFT CARGO DOORS - LATCH PIN INSPECTIONS
(SHEET 2 OF 3)
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BOEING PROPRIETARY -
Copyright © Unpublished Work - See page 1 for details.  38 of 81

### Page 39

The step numbers shown below agree with the numbers shown in the circle symbols in the figure.
MORE DATAQTYIDENTIFICATIONNAMETASKSTEP
(a)869B02005-( )LATCH PINInspect1
(b)869B02005-( )LATCH PINInspect2
(a) Do a general visual inspection of the latch pin to find if the pin is broken into two or more pieces or is
missing.
(b) Do a detailed inspection of the visible external surfaces of the latch pin for cracking. Removal of the
bearing plate is not required. This step is not necessary if the latch pin is broken.
FIGURE 1: LOWER LOBE FORWARD AND AFT CARGO DOORS - LATCH PIN INSPECTIONS
(SHEET 3 OF 3)
BOEING PROPRIETARY -
Copyright © Unpublished Work - See page 1 for details.
Original Issue: October 28, 2010
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ALERTALERT

### Page 40 (OCR)

BOEING SERVICE BULLETIN 747-53A2835
ALERT  ALERT
This Figure applies only to: Group 1-2, Configuration 1; Group 3.
NOTE:
NUMBERS ADJACENT TO
LATCH FITTINGS DENOTE
LATCH FITTING LOCATIONS
DOORWAY LOWER SILL
- LOCATION:
OME STRUCTURE NOT SHOWN FOR CLARIT
1980858
FIGURE 2: LOWER LOBE FORWARD AND AFT CARGO DOORS - LATCH PIN REPLACEMENT
(SHEET 1 OF 5)
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### Page 41 (OCR)

BOEING SERVICE BULLETIN 747-53A2835
ALERT  ALERT
TYPICAL
LATCH FITTING LOCATIONS
1, 3, 5 AND 7
B
INBD
A-A  1980898
FIGURE 2: LOWER LOBE FORWARD AND AFT CARGO DOORS - LATCH PIN REPLACEMENT
(SHEET 2 OF 5)
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### Page 42 (OCR)

BOEING SERVICE BULLETIN 747-53A2835
ALERT  ALERT
B
TYPICAL
LATCH FITTING LOCATIONS
2, 4, 6 AND 8
C
INBD
B-B  1981399
FIGURE 2: LOWER LOBE FORWARD AND AFT CARGO DOORS - LATCH PIN REPLACEMENT
(SHEET 3 OF 5)
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Copyright © Unpublished Work - See page 1 for details.  42 of 81

### Page 43

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 to replace all latch pins in this figure. It may not be
necessary to replace all latch pins.
MORE DATAQTYIDENTIFICATIONNAMETASKSTEP
(a)--SEALANTRemove1
(a)8-BOLTRemove / Keep2
(a)8-WASHERRemove / Keep
(a)8-BRACKET ASSYRemove / Keep
(a) (b)869B02005-( )LATCH PINRemove3
(a) (c)869B02005-6
(69B02005-4 or
69B02005-5 optional)
LATCH PINInstall (New)4
(a)8-BOLTInstall (Kept)5
(a)8-WASHERInstall (Kept)
(a)8-BRACKET ASSYInstall (Kept)
(a) (d)-BMS5-95 TYPE 1,
CLASS B
PRESSURE AND ENVI-
RONMENTAL
SEALANT-CHROMATE
TYPE
Apply6
(e)--SEALANTRemove7
(e)8-BOLTRemove / Keep8
(e)8-WASHERRemove / Keep
(e)8-BRACKET ASSYRemove / Keep
(e) (b)869B02005-( )LATCH PINRemove9
(e) (c)869B02005-6
(69B02005-4 or
69B02005-5 optional)
LATCH PINInstall (New)10
(e)8-BOLTInstall (Kept)11
(e)8-WASHERInstall (Kept)
(e)8-BRACKET ASSYInstall (Kept)
(e) (d)-BMS5-95 TYPE 1,
CLASS B
PRESSURE AND ENVI-
RONMENTAL
SEALANT-CHROMATE
TYPE
Apply12
(a) Do this step where a new latch pin is being installed at latch fitting locations 1, 3, 5 and/or 7.
(b) Discard broken or cracked latch pins and discard latch pins adjacent to broken latch pins.
FIGURE 2: LOWER LOBE FORWARD AND AFT CARGO DOORS - LATCH PIN REPLACEMENT
(SHEET 4 OF 5)
BOEING PROPRIETARY -
Copyright © Unpublished Work - See page 1 for details.
Original Issue: October 28, 2010
747-53A2835
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BOEING SERVICE BULLETIN 747-53A2835
ALERTALERT

### Page 44

MORE DATAQTYIDENTIFICATIONNAMETASKSTEP
(c) Install latch pin wet with BMS5-95 TYPE 1, CLASS B sealant on the faying surface. Make sure sealant
is applied to both the outside diameter of the latch pin and the inside diameter of the latch fitting. Make
sure all excess sealant is removed. Refer to SOPM 20-50-19 as an accepted procedure.
(d) Refer to SOPM 20-50-19 as an accepted procedure.
(e) Do this step where a new latch pin is being installed at latch fitting locations 2, 4, 6 and/or 8.
FIGURE 2: LOWER LOBE FORWARD AND AFT CARGO DOORS - LATCH PIN REPLACEMENT
(SHEET 5 OF 5)
BOEING PROPRIETARY -
Copyright © Unpublished Work - See page 1 for details.
Original Issue: October 28, 2010
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ALERTALERT

### Page 45 (OCR)

BOEING SERVICE BULLETIN 747-53A2835
ALERT  ALERT
This Figure applies only to: Group 1-2, Configuration 2.
NOTE:
NUMBERS ADJACENT TO
LATCH FITTINGS DENOTE
LATCH FITTING LOCATIONS
DOORWAY LOWER SILL
2 LOCATIONS
SOME STRUCTURE NOT SHOWN FOR CLARITY
1980859
FIGURE 3: LOWER LOBE FORWARD AND AFT CARGO DOORS - LATCH PIN REPLACEMENT
(SHEET 1 OF 5)
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### Page 46 (OCR)

BOEING SERVICE BULLETIN 747-53A2835
ALERT  ALERT
TYPICAL
LATCH FITTING LOCATIONS
1, 3, 5 AND 7
INBD
A-A  1981400
FIGURE 3: LOWER LOBE FORWARD AND AFT CARGO DOORS - LATCH PIN REPLACEMENT
(SHEET 2 OF 5)
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### Page 47 (OCR)

BOEING SERVICE BULLETIN 747-53A2835
ALERT  ALERT
B
TYPICAL
I LATCH FITTING LOCATIONS
2, 4, 6 AND 8
1 12
INBD
B-B  1981401
FIGURE 3: LOWER LOBE FORWARD AND AFT CARGO DOORS - LATCH PIN REPLACEMENT
(SHEET 3 OF 5)
Original Issue: October 28, 2010
747-53A2835
BOEING PROPRIETARY -
Copyright © Unpublished Work - See page 1 for details.  47 of 81

### Page 48

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 to replace all latch pins in this figure. It may not be
necessary to replace all latch pins.
MORE DATAQTYIDENTIFICATIONNAMETASKSTEP
(a)--SEALANTRemove1
(a)8-BOLTRemove / Keep2
(a)8-WASHERRemove / Keep
(a)8-NUTRemove / Keep
(a) (b)869B02005-( )LATCH PINRemove3
(a) (c)869B02005-6
(69B02005-4 or
69B02005-5 optional)
LATCH PINInstall (New)4
(a)8-BOLTInstall (Kept)5
(a)8-WASHERInstall (Kept)
(a)8-NUTInstall (Kept)
(a) (d)-BMS5-95 TYPE 1,
CLASS B
PRESSURE AND ENVI-
RONMENTAL
SEALANT-CHROMATE
TYPE
Apply6
(e)--SEALANTRemove7
(e)8-BOLTRemove / Keep8
(e)8-WASHERRemove / Keep
(e)8-NUTRemove / Keep
(e) (b)869B02005-( )LATCH PINRemove9
(e) (c)869B02005-6
(69B02005-4 or
69B02005-5 optional)
LATCH PINInstall (New)10
(e)8-BOLTInstall (Kept)11
(e)8-WASHERInstall (Kept)
(e)8-NUTInstall (Kept)
(e) (d)-BMS5-95 TYPE 1,
CLASS B
PRESSURE AND ENVI-
RONMENTAL
SEALANT-CHROMATE
TYPE
Apply12
(a) Do this step where a new latch pin is being installed at latch fitting locations 1, 3, 5 and/or 7.
(b) Discard broken or cracked latch pins and discard latch pins adjacent to broken latch pins.
FIGURE 3: LOWER LOBE FORWARD AND AFT CARGO DOORS - LATCH PIN REPLACEMENT
(SHEET 4 OF 5)
BOEING PROPRIETARY -
Copyright © Unpublished Work - See page 1 for details.
Original Issue: October 28, 2010
747-53A2835
48 of 81
BOEING SERVICE BULLETIN 747-53A2835
ALERTALERT

### Page 49

MORE DATAQTYIDENTIFICATIONNAMETASKSTEP
(c) Install latch pin wet with BMS5-95 TYPE 1, CLASS B sealant on the faying surface. Make sure sealant
is applied to both the outside diameter of the latch pin and the inside diameter of the latch fitting. Make
sure all excess sealant is removed. Refer to SOPM 20-50-19 as an accepted procedure.
(d) Refer to SOPM 20-50-19 as an accepted procedure.
(e) Do this step where a new latch pin is being installed at latch fitting locations 2, 4, 6 and/or 8.
FIGURE 3: LOWER LOBE FORWARD AND AFT CARGO DOORS - LATCH PIN REPLACEMENT
(SHEET 5 OF 5)
BOEING PROPRIETARY -
Copyright © Unpublished Work - See page 1 for details.
Original Issue: October 28, 2010
747-53A2835
49 of 81
BOEING SERVICE BULLETIN 747-53A2835
ALERTALERT

### Page 50 (OCR)

BOEING SERVICE BULLETIN 747-53A2835
ALERT  ALERT
This Figure applies only to: Group 1, Configuration 3.
NOTE:
NUMBERS ADJACENT TO
LATCH FITTINGS DENOTE
LATCH FITTING LOCATIONS
DOORWAY LOWER SILL
- LOCATION:
OME STRUCTURE NOT SHOWN FOR CLARIT
1984399
FIGURE 4: LOWER LOBE FORWARD AND AFT CARGO DOORS - LATCH PIN REPLACEMENT
(SHEET 1 OF 5)
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### Page 51 (OCR)

BOEING SERVICE BULLETIN 747-53A2835
ALERT  ALERT
TYPICAL
LATCH FITTING LOCATIONS
1, 3, 5 AND 7
B
INBD
A-A  1984401
FIGURE 4: LOWER LOBE FORWARD AND AFT CARGO DOORS - LATCH PIN REPLACEMENT
(SHEET 2 OF 5)
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### Page 52 (OCR)

BOEING SERVICE BULLETIN 747-53A2835
ALERT  ALERT
B  (10
TYPICAL
LATCH FITTING LOCATIONS
2, 4, 6 AND 8
C
INBD
B-B  1984406
FIGURE 4: LOWER LOBE FORWARD AND AFT CARGO DOORS - LATCH PIN REPLACEMENT
(SHEET 3 OF 5)
Original Issue: October 28, 2010
747-53A2835
BOEING PROPRIETARY -
Copyright © Unpublished Work - See page 1 for details.  52 of 81

### Page 53

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 to replace all latch pins in this figure. It may not be
necessary to replace all latch pins.
MORE DATAQTYIDENTIFICATIONNAMETASKSTEP
(a)--SEALANTRemove1
(a)8-BOLTRemove / Keep2
(a)8-WASHERRemove / Keep
(a)8-BRACKET ASSYRemove / Keep
(a) (b)869B02005-( )LATCH PINRemove3
(a) (c)869B02005-3LATCH PINInstall (New)4
(a)8-BOLTInstall (Kept)5
(a)8-WASHERInstall (Kept)
(a)8-BRACKET ASSYInstall (Kept)
(a) (d)-BMS5-95 TYPE 1,
CLASS B
PRESSURE AND ENVI-
RONMENTAL
SEALANT-CHROMATE
TYPE
Apply6
(e)--SEALANTRemove7
(e)8-BOLTRemove / Keep8
(e)8-WASHERRemove / Keep
(e)8-BRACKET ASSYRemove / Keep
(e) (b)869B02005-( )LATCH PINRemove9
(e) (c)869B02005-3LATCH PINInstall (New)10
(e)8-BOLTInstall (Kept)11
(e)8-WASHERInstall (Kept)
(e)8-BRACKET ASSYInstall (Kept)
(e) (d)-BMS5-95 TYPE 1,
CLASS B
PRESSURE AND ENVI-
RONMENTAL
SEALANT-CHROMATE
TYPE
Apply12
(a) Do this step where a new latch pin is being installed at latch fitting locations 1, 3, 5 and/or 7.
(b) Discard broken or cracked latch pins and discard latch pins adjacent to broken latch pins.
(c) Install latch pin wet with BMS5-95 TYPE 1, CLASS B sealant on the faying surface. Make sure sealant
is applied to both the outside diameter of the latch pin and the inside diameter of the latch fitting. Make
sure all excess sealant is removed. Refer to SOPM 20-50-19 as an accepted procedure.
FIGURE 4: LOWER LOBE FORWARD AND AFT CARGO DOORS - LATCH PIN REPLACEMENT
(SHEET 4 OF 5)
BOEING PROPRIETARY -
Copyright © Unpublished Work - See page 1 for details.
Original Issue: October 28, 2010
747-53A2835
53 of 81
BOEING SERVICE BULLETIN 747-53A2835
ALERTALERT

### Page 54

MORE DATAQTYIDENTIFICATIONNAMETASKSTEP
(d) Refer to SOPM 20-50-19 as an accepted procedure.
(e) Do this step where a new latch pin is being installed at latch fitting locations 2, 4, 6 and/or 8.
FIGURE 4: LOWER LOBE FORWARD AND AFT CARGO DOORS - LATCH PIN REPLACEMENT
(SHEET 5 OF 5)
BOEING PROPRIETARY -
Copyright © Unpublished Work - See page 1 for details.
Original Issue: October 28, 2010
747-53A2835
54 of 81
BOEING SERVICE BULLETIN 747-53A2835
ALERTALERT

### Page 55 (OCR)

BOEING SERVICE BULLETIN 747-53A2835
ALERT  ALERT
This Figure applies only to: Group 1, Configuration 4.
NOTE:
NUMBERS ADJACENT TO
LATCH FITTINGS DENOTE
LATCH FITTING LOCATIONS
DOORWAY LOWER SILL
2 LOCATIONS
SOME STRUCTURE NOT SHOWN FOR CLARITY
1984408
FIGURE 5: LOWER LOBE FORWARD AND AFT CARGO DOORS - LATCH PIN REPLACEMENT
(SHEET 1 OF 5)
Original Issue: October 28, 2010
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Copyright © Unpublished Work - See page 1 for details.  55 of 81

### Page 56 (OCR)

BOEING SERVICE BULLETIN 747-53A2835
ALERT  ALERT
TYPICAL
LATCH FITTING LOCATIONS
1, 3, 5 AND 7
INBD
A-A  1984410
FIGURE 5: LOWER LOBE FORWARD AND AFT CARGO DOORS - LATCH PIN REPLACEMENT
(SHEET 2 OF 5)
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### Page 57 (OCR)

BOEING SERVICE BULLETIN 747-53A2835
ALERT  ALERT
B
TYPICAL
I LATCH FITTING LOCATIONS
2, 4, 6 AND 8
1 12
INBD
B-B  1984411
FIGURE 5: LOWER LOBE FORWARD AND AFT CARGO DOORS - LATCH PIN REPLACEMENT
(SHEET 3 OF 5)
Original Issue: October 28, 2010
747-53A2835
BOEING PROPRIETARY -
Copyright © Unpublished Work - See page 1 for details.  57 of 81

### Page 58

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 to replace all latch pins in this figure. It may not be
necessary to replace all latch pins.
MORE DATAQTYIDENTIFICATIONNAMETASKSTEP
(a)--SEALANTRemove1
(a)8-BOLTRemove / Keep2
(a)8-WASHERRemove / Keep
(a)8-NUTRemove / Keep
(a) (b)869B02005-( )LATCH PINRemove3
(a) (c)869B02005-3LATCH PINInstall (New)4
(a)8-BOLTInstall (Kept)5
(a)8-WASHERInstall (Kept)
(a)8-NUTInstall (Kept)
(a) (d)-BMS5-95 TYPE 1,
CLASS B
PRESSURE AND ENVI-
RONMENTAL
SEALANT-CHROMATE
TYPE
Apply6
(e)--SEALANTRemove7
(e)8-BOLTRemove / Keep8
(e)8-WASHERRemove / Keep
(e)8-NUTRemove / Keep
(e) (b)869B02005-( )LATCH PINRemove9
(e) (c)869B02005-3LATCH PINInstall (New)10
(e)8-BOLTInstall (Kept)11
(e)8-WASHERInstall (Kept)
(e)8-NUTInstall (Kept)
(e) (d)-BMS5-95 TYPE 1,
CLASS B
PRESSURE AND ENVI-
RONMENTAL
SEALANT-CHROMATE
TYPE
Apply12
(a) Do this step where a new latch pin is being installed at latch fitting locations 1, 3, 5 and/or 7.
(b) Discard broken or cracked latch pins and discard latch pins adjacent to broken latch pins.
(c) Install latch pin wet with BMS5-95 TYPE 1, CLASS B sealant on the faying surface. Make sure sealant
is applied to both the outside diameter of the latch pin and the inside diameter of the latch fitting. Make
sure all excess sealant is removed. Refer to SOPM 20-50-19 as an accepted procedure.
FIGURE 5: LOWER LOBE FORWARD AND AFT CARGO DOORS - LATCH PIN REPLACEMENT
(SHEET 4 OF 5)
BOEING PROPRIETARY -
Copyright © Unpublished Work - See page 1 for details.
Original Issue: October 28, 2010
747-53A2835
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BOEING SERVICE BULLETIN 747-53A2835
ALERTALERT

### Page 59

MORE DATAQTYIDENTIFICATIONNAMETASKSTEP
(d) Refer to SOPM 20-50-19 as an accepted procedure.
(e) Do this step where a new latch pin is being installed at latch fitting locations 2, 4, 6 and/or 8.
FIGURE 5: LOWER LOBE FORWARD AND AFT CARGO DOORS - LATCH PIN REPLACEMENT
(SHEET 5 OF 5)
BOEING PROPRIETARY -
Copyright © Unpublished Work - See page 1 for details.
Original Issue: October 28, 2010
747-53A2835
59 of 81
BOEING SERVICE BULLETIN 747-53A2835
ALERTALERT

### Page 60 (OCR)

BOEING SERVICE BULLETIN 747-53A2835
ALERT  ALERT
This Figure applies only to: Group 1, Configuration 3.
NOTE:
NUMBERS ADJACENT TO
LATCH FITTINGS DENOTE
LATCH FITTING LOCATIONS
DOORWAY LOWER SILL
- LOCATION:
OME STRUCTURE NOT SHOWN FOR CLARITI
2003528
FIGURE 6: LOWER LOBE FORWARD AND AFT CARGO DOORS - LATCH PIN AND BEARING PLATE
MODIFICATION OR REPLACEMENT
(SHEET 1 OF 11)
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