Commercial 

Airplanes 757

Service Bulletin

ALERT

Number: 757-52A0091

Original Issue: March 09, 2010

Revision 1: December 19, 2014

ATA System: 5232

SUBJECT: DOORS - Main Cargo Door - Cam Latch and Latch Pin Inspection and Modification

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.

ECCN: 9E991

BOEING PROPRIETARY, CONFIDENTIAL AND/OR TRADE SECRET

Copyright © 2010 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Unpublished Work.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.

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3.0
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BOEING SERVICE BULLETIN 757-52A0091

ALERT ALERT

BLANK PAGE
Table of Contents

Revision Transmittal Sheet ............................................ 5

Summary ...................................................... 7

1. PLANNING INFORMATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11

A. Effectivity . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11

1. Airplanes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11

2. Spares Affected . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12

B. Concurrent Requirements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12

C. Reason . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12

D. Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13

E. Compliance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13

F. Approval . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24

G. Manpower . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25

H. Weight and Balance Changes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26

I. Electrical Load Data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26

J. References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26

1. Existing Data: . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26

2. Data Supplied with this Service Bulletin: . . . . . . . . . . . . . . . . . . . . . . . . . . . 26

3. Installation Drawings Used in the Preparation of this Service Bulletin: . . . . . . . . . . . 26

K. Publications Affected . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27

L. Interchangeability and Intermixability of Parts . . . . . . . . . . . . . . . . . . . . . . . . . . . 27

M. Software Accomplishment Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27

2. MATERIAL INFORMATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29

A. Material - Price and Availability . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29

B. Industry Support Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29

C. Parts Necessary for Each Airplane . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29

1. Kits/Parts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29

2. Parts and Materials Supplied by the Operator . . . . . . . . . . . . . . . . . . . . . . . . 29

3. Parts Modified and Reidentified . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29

4. Parts Removed and Not Replaced . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30

D. Parts Necessary to Change Spares . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30

E. Special Tooling - Price and Availability . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30

F. Special Tooling Necessary to do this Service Bulletin . . . . . . . . . . . . . . . . . . . . . . . 30

3. ACCOMPLISHMENT INSTRUCTIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31

A. GENERAL INFORMATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31

B. WORK INSTRUCTIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32

FIGURE 1: MAIN CARGO DOOR - CAM LATCHES AND LATCH PINS INSPECTION . . . . . . . . . 37

FIGURE 2: MAIN CARGO DOOR - LATCH PIN CROSS BOLT TORQUE . . . . . . . . . . . . . . . . 40

FIGURE 3: MAIN CARGO DOOR - LATCH PIN EXTENSION MEASUREMENT . . . . . . . . . . . . 42

FIGURE 4: MAIN CARGO DOOR - CAM LATCH 1 AND CAM LATCH 2 INSPECTION . . . . . . . . 44

FIGURE 5: MAIN CARGO DOOR - LATCH PIN CROSS BOLT REPLACEMENT . . . . . . . . . . . 46

FIGURE 6: MAIN CARGO DOOR - CAM LATCH REPLACEMENT . . . . . . . . . . . . . . . . . . . 48

FIGURE 7: MAIN CARGO DOOR - LATCH PIN REPLACEMENT . . . . . . . . . . . . . . . . . . . . 51

FIGURE 8: MAIN CARGO DOOR - CAM LATCH REMOVAL AND INSPECTION . . . . . . . . . . . 53

FIGURE 9: MAIN CARGO DOOR - CAM LATCHES, LATCH PINS AND LATCH PIN CROSS BOLTS

INSPECTION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 56

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BOEING SERVICE BULLETIN 757-52A0091

ALERT ALERT
FIGURE 10: MAIN CARGO DOOR - CAM LATCH AND LATCH PIN RIGGING . . . . . . . . . . . . . 58

FIGURE 11: MAIN CARGO DOOR - MAIN CARGO DOOR EDGE FLUSHNESS MEASUREMENT . . 61

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BOEING SERVICE BULLETIN 757-52A0091

ALERT ALERT
Commercial 

Airplanes 757

Service Bulletin

ALERT

Revision Transmittal Sheet Number: 757-52A0091

Original Issue: March 09, 2010

Revision 1: December 19, 2014

ATA System: 5232

SUBJECT: DOORS - Main Cargo Door - Cam Latch and Latch Pin Inspection and Modification

This revision includes all pages of the service bulletin.

COMPLIANCE INFORMATION RELATED TO THIS REVISION

Federal Aviation Administration (FAA) Notice of Proposed Rule Making NPRM 2011-NM-163-AD, is related to

this service bulletin.

No more work is necessary on the airplane(s) changed or inspected in accordance with the original issue of this

service bulletin.

REASON FOR REVISION

This revision is sent to clarify the requirements of the compliance tables.

These sections were changed:

1. Summary

a. Background:

(1) Background statement revised and new service history information was added.

(2) Summary Evaluation Table added.

b. Action - Changed to agree with work instructions.

c. Compliance - NPRM statement added.

2. Planning Information

a. Reason - Added the reason for Revision 1 is sent to statement.

b. Description - Changed to agree with work instructions.

c. Compliance:

(1) NPRM statement added.

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(2) Compliance Tables 1 and 2 revised to clarify inspections, conditions and actions.

3. Accomplishment Instructions

a. General Information - Notes numbering has been changed and new notes added.

b. Work Instructions - Revised for clarification.

Vertical lines are put on the left edge of each page, except in Paragraph 1.A., Effectivity and format changes,

to show the location of all content changes.

Pages with no vertical lines have no changes.

REVISION HISTORY

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BOEING SERVICE BULLETIN 757-52A0091

ALERT ALERT
Commercial 

Airplanes 757

Service Bulletin

ALERT

Summary Number: 757-52A0091

Original Issue: March 09, 2010

Revision 1: December 19, 2014

ATA System: 5232

SUBJECT: DOORS - Main Cargo Door - Cam Latch and Latch Pin Inspection and Modification

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

Accomplishment of the inspections in this service bulletin will make sure the Main Cargo Door (MCD) cam latches

are inspected for damage and the latch pins are inspected for damage and migration. The inspections are

necessary in order to find and replace damaged cam latches, latch pins and latch pin cross bolts. If not replaced,

damaged cam latches, latch pins and latch pin cross bolts could lead to a failure of the cam latches and may

result in a possible rapid decompression and potential separation of the cargo door from the airplane.

Boeing has received one report from one operator that the MCD forward most cam latch on the forward center

cam latch pair (cam latch number 3) broke during flight. The airplane that reported the broken cam latch had

20,000 flight hours and 9,500 flight cycles when the cam latch broke. The crew heard a loud noise coming from

the MCD shortly after cruise. Upon landing, an inspection was performed and a cam latch was found broken.

The broken cam latch mating latch pin was also found to have significant wear as evidenced by the loss of the

plating on the surface that is normally in contact with the cam. The latch pin was also deformed approximately

0.05 inch in the area of the wear surface.

The cause of the broken cam latch has been determined to be from a poorly rigged MCD. Although rigged per

the original Aircraft Maintenance Manual (AMM) procedures, significant variation was allowed in the rigging

dimensions. This variation can cause some of the latch pin/cam latch locations to have a significant preload

placed on them during engagement and rotation of the cam latches during latching and unlatching operations.

This preload is believed to have imparted a torque on the latch pin from the cam latch rotation during latching

and unlatching operations. The torque transmitted to the latch pin is then believed to have caused the latch pin

cross bolt to fail in shear.

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If the latch pin cross bolt fails, the latch pin could migrate either towards the cam latch or away from the cam

latch. Latch pin migration towards the cam latch can cause significant interference with the mating cam latch

leading to cam latch damage. In this case, the latch pin migrated into the cam latch and caused damage to the

cam latch. The crack initiated at the damage site caused by the latch pin and then led to the cam latch breaking.

Latch pin migration away from the cam latch could cause disengagement from the cam latch, resulting in no

load transfer between the cam latch and the mating latch pin and may not be noticed before critical conditions

are exceeded in adjacent cam latches or latch pins.

Accomplishment of the work given in this service bulletin will make sure the cam latches, latch pins and latch

pin cross bolt are inspected and repaired or replaced as required. The MCD rig will be verified to the Service

Bulletin requirements and if necessary, the MCD will be re-rigged to the updated AMM requirements.

Since the original report, there have been two additional reports of sheared latch pin cross bolts.

Boeing Service Related Problem (SRP) 757-SRP-52-0088 is related to this service bulletin.

This table is provided to operators for planning purposes only. Refer to the applicable sections for more

information.

Planning Data Affected Reference

Spares Affected No Paragraph 1.A.2., Spares Affected

Paragraph 1.E., Compliance and Paragraph

1.F., Approval

AD Related Yes

Weight and Balance Change No Paragraph 1.H., Weight and Balance Changes

Electrical Load Changed No Paragraph 1.I., Electrical Load Data

Publications Affected Yes Paragraph 1.K., Publications Affected

Airplane Flight Operations Affected (Flight Crew No Paragraph 1.K., Publications Affected

Operations Manual and/or FAA Approved Airplane Flight Manual)

Kits/Parts Required No Paragraph 2.C.1., Kits/Parts

Paragraph 2.C.2., Parts and Materials Supplied

by the Operator

Operator Supplied Parts/Material No

Paragraph 2.F., Special Tooling Necessary to

do this Service Bulletin

Special Tooling Required No

ACTION

Get access to the MCD. Do a general visual inspection of the cam latches, latch pins and latch pin cross bolt.

Torque the cross bolts in the latch pins. Measure the extension of the latch pins. Replace all alloy steel cross

bolts through the latch pins with Corrosion Resistant Steel (CRES) cross bolts. Check for lip deformation on all

cam latches. Do a High Frequency Eddy Current (HFEC) or magnetic particle inspection of cam latch 1 and

cam latch 2 for cracks. Replace any cracked or broken parts. Check the rig of the MCD to the requirements of

the Service Bulletin and if necessary, the MCD will be re-rigged to the latest AMM requirements. Do repetitive

general visual and detailed inspections of the cam latches and latch pins after the rig is verified or adjusted. Do

repetitive HFEC or magnetic particle inspections of cam latch 1 and cam latch 2 for cracks after the rig is verified

or adjusted.

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BOEING SERVICE BULLETIN 757-52A0091

ALERT ALERT
EFFECTIVITY

757-200CB, 757-200PF and 757-200 Special Freighter delivered under a Boeing Supplemental Type Certificate

(STC) Airplanes. Refer to Paragraph 1.A.1., Airplanes for the list of affected airplanes.

COMPLIANCE

Federal Aviation Administration (FAA) Notice of Proposed Rule Making NPRM 2011-NM-163-AD, is related to

this service bulletin.

Refer to Paragraph 1.E., Compliance.

INDUSTRY SUPPORT INFORMATION

Boeing warranty remedies are not available for the inspections and modifications 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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ALERT ALERT
Export Controlled ECCN: 9E991 - BOEING

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BOEING SERVICE BULLETIN 757-52A0091

ALERT ALERT
Commercial 

Airplanes 757

Service Bulletin

ALERT

Number: 757-52A0091

Original Issue: March 09, 2010

Revision 1: December 19, 2014

ATA System: 5232

SUBJECT: DOORS - Main Cargo Door - Cam Latch and Latch Pin Inspection and Modification

THIS BULLETIN IS SENT TO THE OPERATORS OF RECORD OF THE AIRPLANES SHOWN IN PARAGRAPH

1.A., EFFECTIVITY. IF AN AIRPLANE HAS BEEN LEASED OR SOLD, SEND THIS SERVICE BULLETIN TO

THE NEW OPERATOR. IF APPLICABLE SPARES HAVE BEEN SOLD, SEND THIS SERVICE BULLETIN TO

THE NEW OWNER.

1. PLANNING INFORMATION

A. Effectivity

1. Airplanes

Refer to Service Bulletin Index Document D624N001 Part 3 for Airplane Variable Number, Line

Number, and Serial Number data.

This service bulletin is for the airplanes shown below.

GROUP CONFIGURATION DESCRIPTION

757-200PF, 757-200CB and 757-200 Special Freighter delivered

under a Boeing Supplemental Type Certificate (STC) Airplanes

1 -

Airplane Models:

757-200, 757-200CB, 757-200PF

Variable Number Group

NA201 - NA204 1

NA206 - NA213 1

NA215 - NA236 1

NC901 - NC951 1

NC971 1

NC973 - NC974 1

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Variable Number Group

ND895 1

NS601 - NS616 1

NT001 - NT009 1

2. Spares Affected

None.

B. Concurrent Requirements

None.

C. Reason

Accomplishment of the inspections in this service bulletin will make sure the Main Cargo Door (MCD)

cam latches are inspected for damage and the latch pins are inspected for damage and migration. The

inspections are necessary in order to find and replace damaged cam latches, latch pins and latch pin

cross bolts. If not replaced, damaged cam latches, latch pins and latch pin cross bolts could lead to a

failure of the cam latches and may result in a possible rapid decompression and potential separation

of the cargo door from the airplane.

Boeing has received one report from one operator that the MCD forward most cam latch on the forward

center cam latch pair (cam latch number 3) broke during flight. The airplane that reported the broken

cam latch had 20,000 flight hours and 9,500 flight cycles when the cam latch broke. The crew heard

a loud noise coming from the MCD shortly after cruise. Upon landing, an inspection was performed

and a cam latch was found broken. The broken cam latch mating latch pin was also found to have

significant wear as evidenced by the loss of the plating on the surface that is normally in contact with

the cam. The latch pin was also deformed approximately 0.05 inch in the area of the wear surface.

The cause of the broken cam latch has been determined to be from a poorly rigged MCD. Although

rigged per the original Aircraft Maintenance Manual (AMM) procedures, significant variation was allowed

in the rigging dimensions. This variation can cause some of the latch pin/cam latch locations to have

a significant preload placed on them during engagement and rotation of the cam latches during latching

and unlatching operations. This preload is believed to have imparted a torque on the latch pin from the

cam latch rotation during latching and unlatching operations. The torque transmitted to the latch pin is

then believed to have caused the latch pin cross bolt to fail in shear.

If the latch pin cross bolt fails, the latch pin could migrate either towards the cam latch or away from

the cam latch. Latch pin migration towards the cam latch can cause significant interference with the

mating cam latch leading to cam latch damage. In this case, the latch pin migrated into the cam latch

and caused damage to the cam latch. The crack initiated at the damage site caused by the latch pin

and then led to the cam latch breaking. Latch pin migration away from the cam latch could cause

disengagement from the cam latch, resulting in no load transfer between the cam latch and the mating

latch pin and may not be noticed before critical conditions are exceeded in adjacent cam latches or

latch pins.

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BOEING SERVICE BULLETIN 757-52A0091

ALERT ALERT
Accomplishment of the work given in this service bulletin will make sure the cam latches, latch pins

and latch pin cross bolts are inspected and repaired or replaced as required. The MCD rig will be

verified to the Service Bulletin requirements and if necessary, the MCD will be re-rigged to the latest

AMM requirements.

Since the original report, there have been two additional reports of a sheared latch pin cross bolts.

Boeing Service Related Problem (SRP) 757-SRP-52-0088 is related to this service bulletin.

Revision 1 is sent to clarify the requirements of the compliance tables.

D. Description

Get access to the MCD. Do a general visual inspection of the cam latches, latch pins and latch pin

cross bolts. Torque the cross bolts in the latch pins. Measure the extension of the latch pins. Replace

all alloy steel cross bolts through the latch pins with CRES cross bolts. Check for lip deformation on

all cam latches. Do a HFEC or magnetic particle inspection of cam latch 1 and cam latch 2 for cracks.

Replace any cracked or broken parts. The MCD rig will be verified to the Service Bulletin requirements

and if necessary, the MCD will be re-rigged to the updated AMM requirements. Do repetitive general

visual and detailed inspections of the cam latches and latch pins after the rig is verified or adjusted.

Do repetitive HFEC or magnetic particle inspections of cam latch 1 and cam latch 2 for cracks after

the rig is verified or adjusted.

Effects of this Issue on airplanes on which Original Issue was previously done:

None

The work in this service bulletin is done in the maintenance zone(s) given below.

Affected Maintenance Zones

Model Zone

757-200, 757-200CB, 757- 838

200PF

E. Compliance

Federal Aviation Administration (FAA) Notice of Proposed Rule Making NPRM 2011-NM-163-AD, is

related to this service bulletin.

If all Table 1 requirements, including rigging of the main cargo door, have been accomplished in

accordance with the original issue of this service bulletin, continue repetitive inspections in accordance

with Table 2.

If Table 1 requirements have not been accomplished in accordance with the original issue of this service

bulletin, then all Table 1 requirements, including rigging of the main cargo door, must be accomplished

before starting Table 2 requirements.

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BOEING SERVICE BULLETIN 757-52A0091

ALERT ALERT
Table 1: Initial and Repetitive Inspections of the Cam Latches, Latch Pins and Latch Pin Cross Bolts for

the Main Cargo Door (Pre-Rig Check)

Repeat Interval (Not to

Exceed)

Compliance Time (Whichever

Occurs First)

Condition Action

Within 150 days -

after the original issue date

of this service

bulletin.

Within 330 flight

cycles after the

original issue

date of this service bulletin.

Do the following for all

MCD cam latches and

latch pins:

Do a general visual inspection for any broken

cam latches, latch pins

and latch pin cross bolts,

and for any missing cam

latches, latch pins and

latch pin cross bolts in

accordance with Paragraph 3.B., Work Instructions Step 1.b.

All airplanes

AND

Torque the cross bolts in

the latch pins in accordance with Paragraph

3.B., Work Instructions

Step 1.c.

AND

Measure the extension

of the latch pins in accordance with Paragraph

3.B., Work Instructions

Step 1.d.

AND

Do a general visual inspection of all cam

latches for lip deformation in accordance with

Paragraph 3.B., Work

Instructions Step 1.e.

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BOEING SERVICE BULLETIN 757-52A0091

ALERT ALERT
Table 1: Initial and Repetitive Inspections of the Cam Latches, Latch Pins and Latch Pin Cross Bolts for

the Main Cargo Door (Pre-Rig Check)

Repeat Interval (Not to

Exceed)

Compliance Time (Whichever

Occurs First)

Condition Action

Replace all broken and Before further flight -

missing cam latches,

latch pins and latch pin

cross bolts in accordance with Paragraph

3.B., Work Instructions

Step 2.a.

Condition 1: One or

more of the following is

found:

1. Broken or

missing cam

latch(es).

2. Broken or

missing latch

pin(s).

3. Broken or

missing latch

pin cross

bolt(s).

AND

Do a detailed inspection

of mating part(s) and immediately adjacent cam

latch(es) and latch pin(s)

for any cracks, or any

gouges in critical areas

in accordance with

Paragraph 3.B., Work

Instructions Step 2.b.

AND

Unless replaced with

new or reworked parts,

do a HFEC or magnetic

particle inspection of

cam latch 1 and cam

latch 2 for any cracks in

accordance with Paragraph 3.B., Work Instructions Step 2.c.

(b)

AND

Check the rig of the

MCD in accordance with

Paragraph 3.B., Work

Instructions Step 2.d.

AND

Replace all alloy steel

cross bolts through the

latch pins with CRES

cross bolts in accordance with Paragraph

3.B., Work Instructions

Step 2.d.

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BOEING SERVICE BULLETIN 757-52A0091

ALERT ALERT
Table 1: Initial and Repetitive Inspections of the Cam Latches, Latch Pins and Latch Pin Cross Bolts for

the Main Cargo Door (Pre-Rig Check)

Repeat Interval (Not to

Exceed)

Compliance Time (Whichever

Occurs First)

Condition Action

Within 150 days -

after the latch

pin extension

was measured.

Within 330 flight

cycles after the

latch pin extension was measured.

Replace the discrepant

latch pin in accordance

with Paragraph 3.B.,

Work Instructions Step

3.a.

Condition 2: The latch

pin extension is less

than 0.89 inches or

greater than 0.91 inches.

AND

Do a detailed inspection

of the mating cam latch

for any cracks, or

gouges in critical areas

in accordance with

Paragraph 3.B., Work

Instructions Step 3.b.

330 flight cycles or 150

days, whichever occurs

first. (a)

Within 150 days

after the initial

inspection.

Within 330 flight

cycles after the

initial inspection.

Do the following for all

MCD cam latches and

latch pins:

Do a general visual inspection for any broken

cam latches, latch pins

and latch pin cross bolts,

and for any missing cam

latches, latch pins and

latch pin cross bolts in

accordance with Paragraph 3.B., Work Instructions Step 3.c.

AND

Within 24 -

months after

the original issue date of this

service bulletin.

Within 3,000

flight cycles after the original

issue date of

this service bulletin.

Do a detailed inspection

of all cam latches and

mating latch pins for any

cracks, or gouges in critical areas in accordance

with Paragraph 3.B.,

Work Instructions Step

3.d.

Within 24 -

months after

the original issue date of this

service bulletin.

Within 3,000

flight cycles after the original

issue date of

this service bulletin.

Unless replaced with

new or reworked parts,

do a HFEC or magnetic

particle inspection of

cam latch 1 and cam

latch 2 for any cracks in

accordance with Paragraph 3.B., Work Instructions Step 3.e.

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BOEING SERVICE BULLETIN 757-52A0091

ALERT ALERT
Table 1: Initial and Repetitive Inspections of the Cam Latches, Latch Pins and Latch Pin Cross Bolts for

the Main Cargo Door (Pre-Rig Check)

Repeat Interval (Not to

Exceed)

Compliance Time (Whichever

Occurs First)

Condition Action

(b)

AND

Check the rig of the

MCD in accordance with

Paragraph 3.B., Work

Instructions Step 3.f.

AND

Replace all alloy steel

cross bolts through the

latch pins with CRES

cross bolts in accordance with Paragraph

3.B., Work Instructions

Step 3.f.

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ALERT ALERT
Table 1: Initial and Repetitive Inspections of the Cam Latches, Latch Pins and Latch Pin Cross Bolts for

the Main Cargo Door (Pre-Rig Check)

Repeat Interval (Not to

Exceed)

Compliance Time (Whichever

Occurs First)

Condition Action

330 flight cycles or 150

days, whichever occurs

first.

Within 150 days

after the initial

inspection.

Within 330 flight

cycles after the

initial inspection.

Do a detailed inspection

of the discrepant cam

latch and mating latch

pin for any cracks, or

gouges in critical areas

in accordance with

Paragraph 3.B., Work

Instructions Step 4.a.

Condition 3: If a cam

latch is found with lip

deformation.

(a)

AND

330 flight cycles or 150

days, whichever occurs

first.

Within 150 days

after the initial

inspection.

Within 330 flight

cycles after the

initial inspection.

Do the following for all

MCD cam latches and

latch pins:

Do a general visual inspection for any broken

cam latches, latch pins

and latch pin cross bolts,

and for any missing cam

latches, latch pins and

latch pin cross bolts in

accordance with Paragraph 3.B., Work Instructions Step 4.b.

(a)

AND

Within 24 -

months after

the original issue date of the

service bulletin.

Within 3,000

flight cycles after the original

issue date of

the service bulletin.

Do a detailed inspection

of all cam latches and

mating latch pins for any

cracks, or gouges in critical areas in accordance

with Paragraph 3.B.,

Work Instructions Step

4.c.

AND

Within 24 -

months after

the original issue date of the

service bulletin.

Within 3,000

flight cycles after the original

issue date of

the service bulletin.

Unless replaced with

new or reworked parts,

do a HFEC or magnetic

particle inspection of

cam latch 1 and cam

latch 2 for any cracks in

accordance with Paragraph 3.B., Work Instructions Step 4.d.

(b)

AND

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ALERT ALERT
Table 1: Initial and Repetitive Inspections of the Cam Latches, Latch Pins and Latch Pin Cross Bolts for

the Main Cargo Door (Pre-Rig Check)

Repeat Interval (Not to

Exceed)

Compliance Time (Whichever

Occurs First)

Condition Action

Check the rig of the

MCD in accordance with

Paragraph 3.B., Work

Instructions Step 4.e.

AND

Replace all alloy steel

cross bolts through the

latch pins with CRES

cross bolts in accordance with Paragraph

3.B., Work Instructions

Step 4.e.

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ALERT ALERT
Table 1: Initial and Repetitive Inspections of the Cam Latches, Latch Pins and Latch Pin Cross Bolts for

the Main Cargo Door (Pre-Rig Check)

Repeat Interval (Not to

Exceed)

Compliance Time (Whichever

Occurs First)

Condition Action

330 flight cycles or 150

days, whichever occurs

first.

Within 150 days

after the initial

inspection.

Within 330 flight

cycles after the

initial inspection.

Do a general visual inspection for any broken

and missing cam latches, latch pins and latch

pin cross bolts in accordance with Paragraph

3.B., Work Instructions

Step 5.a.

Condition 4: No discrepancies found (c)

(a)

3,000 flight cycles or 24

months, whichever occurs first.

Within 24

months after

the initial inspection.

Within 3,000

flight cycles after the initial inspection.

Do a detailed inspection

of the cam latches and

latch pins for any cracks,

or any gouges in critical

areas in accordance with

Paragraph 3.B., Work

Instructions Step 5.b.

(a)

AND

Unless replaced with

new or reworked parts,

do a HFEC or magnetic

particle inspection of

cam latch 1 and cam

latch 2 for any cracks in

accordance with Paragraph 3.B., Work Instructions Step 5.c.

(b)

Within 48 -

months after

the original issue date of this

service bulletin.

Within 6,000

flight cycles after the original

issue date of

this service bulletin.

Check the rig of the

MCD in accordance with

Paragraph 3.B., Work

Instructions Step 5.d.

AND

Replace all alloy steel

cross bolts through the

latch pins with CRES

cross bolts in accordance with Paragraph

3.B., Work Instructions

Step 5.d.

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ALERT ALERT
Table 1: Initial and Repetitive Inspections of the Cam Latches, Latch Pins and Latch Pin Cross Bolts for

the Main Cargo Door (Pre-Rig Check)

Repeat Interval (Not to

Exceed)

Compliance Time (Whichever

Occurs First)

Condition Action

Replace cracked or Before further flight. -

gouged cam latch(es)

and latch pin(s) in accordance with Paragraph

3.B., Work Instructions

Step 6.a.

Condition 5: If the detailed, HFEC or magnetic particle inspections in

Conditions 1 thru 4 reveal any of the following:

1. Cracked or

gouged cam

latch(es) in critical areas.

2. Cracked or

gouged latch

pin(s) in critical

areas.

AND

Do a detailed inspection

of mating part(s) and immediately adjacent cam

latch(es) and latch pin(s)

for any cracks, or any

gouges in critical areas

in accordance with

Paragraph 3.B., Work

Instructions Step 6.b.

AND

Unless replaced with

new or reworked parts,

do a HFEC or magnetic

particle inspection of

cam latch 1 and cam

latch 2 for any cracks in

accordance with Paragraph 3.B., Work Instructions Step 6.c. (b)

AND

Check the rig of the

MCD in accordance with

Paragraph 3.B., Work

Instructions Step 6.d.

AND

Replace all alloy steel

cross bolts through the

latch pins with CRES

cross bolts in accordance with Paragraph

3.B., Work Instructions

Step 5.e.

(a) All Table 1 repeat inspections are terminated when the rig of the MCD has been checked in accordance

Paragraph 3.B., Work Instructions. Refer to Table 2 for post-rig check inspection requirements.

(b) A reworked cam latch is defined as a cam latch that has been reworked within limits of CMM 52-32-03

and/or a Boeing ODA approved repair via FAA Form 8100-9 and has been HFEC or magnetic particle inspected, and has no crack(s) or gouge(s) in critical area(s).

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BOEING SERVICE BULLETIN 757-52A0091

ALERT ALERT
Table 1: Initial and Repetitive Inspections of the Cam Latches, Latch Pins and Latch Pin Cross Bolts for

the Main Cargo Door (Pre-Rig Check)

Repeat Interval (Not to

Exceed)

Compliance Time (Whichever

Occurs First)

Condition Action

(c) Discrepancy is defined as: Any broken, cracked, missing or gouged cam latches or latch pins, broken or

missing latch pin cross bolts, latch pin extension less than 0.89 inches or greater than 0.91 inches, or cam

latch lip deformation.

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BOEING SERVICE BULLETIN 757-52A0091

ALERT ALERT
Table 2: Repetitive Inspection Requirements for Airplanes that have accomplished All Table 1 Requirements, Including Rigging of the Main Cargo Door in accordance with the Original Issue or Revision 1 of

this service bulletin.

Repeat Interval (Not to

Exceed)

Compliance Time (Whichever Occurs

Later)

Condition Action

375 flight cycles.Within 375 flight cycles after the rig of the

MCD was checked.

Do a general visual inspection for any broken

or missing cam latches,

latch pins and latch pin

cross bolts in accordance

with Paragraph 3.B.,

Work Instructions Step

7.a.1.

Condition 6: Airplanes

that have accomplished

all Table 1 requirements,

including rigging of the

main cargo door in accordance with the original

issue or revision 1 of this

service bulletin and no

rigging adjustment of any

latch pin or any latch pin

fitting was required.

3,000 flight cycles.If latch pin flight cycles are known:

Before 40,000 total latch pin flight cycles.

Do a detailed inspection

of the latch pins for any

cracks, or any gouges in

critical areas in accordance with Paragraph

3.B., Work Instructions

Step 7.a.2.

3,000 flight cycles.If latch pin flight cycles are unknown:

Within 3,000 flight cycles after the rig of

the MCD was checked.

AND

During previous pre-rig

check inspection no discrepancy was found. (b)

3,000 flight cycles.If cam latch flight cycles are known and

cam latch is not a reworked part:

Do a detailed inspection

of the cam latches for

any cracks, or any

gouges in critical areas

in accordance with Paragraph 3.B., Work Instructions Step 7.a.2.

(a)

Before 40,000 total cam latch flight cycles.

3,000 flight cycles.If cam latch flight cycles are unknown or

if cam latch is a reworked part:

(a)

Within 3,000 flight cycles after the rig of

the MCD was checked.

6,000 flight cycles.If cam latch flight cycles are known and

cam latch is not a reworked part:

Do a HFEC or magnetic

particle inspection of cam

latch 1 and cam latch 2

for any cracks in accordance with Paragraph

3.B., Work Instructions

Step 7.a.3.

(a)

Before 40,000 total cam latch flight cycles.

6,000 flight cycles.If cam latch flight cycles are unknown or

if cam latch is a reworked part:

(a)

Within 6,000 flight cycles after the rig of

the MCD was checked.

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ALERT ALERT
Table 2: Repetitive Inspection Requirements for Airplanes that have accomplished All Table 1 Requirements, Including Rigging of the Main Cargo Door in accordance with the Original Issue or Revision 1 of

this service bulletin.

Repeat Interval (Not to

Exceed)

Compliance Time (Whichever Occurs

Later)

Condition Action

375 flight cycles.Within 375 flight cycles after the rig of the

MCD was checked.

Do a general visual inspection for any broken

or missing cam latch(es),

latch pin(s) and latch pin

cross bolt(s) in accordance with Paragraph

3.B., Work Instructions

Step 8.a.1

Condition 7: Airplanes

that have accomplished

all Table 1 requirements,

including rigging of the

main cargo door in accordance with the original

issue or revision 1 of this

service bulletin and rigging adjustment of any

latch pin or any latch pin

fitting was required.

3,000 flight cycles.Within 3,000 flight cycles after the rig of

the MCD was checked.

Do a detailed inspection

of the cam latches and

latch pins for any cracks,

or any gouges in critical

areas in accordance with

Paragraph 3.B., Work Instructions Step 8.a.2

OR

During previous pre-rig

check inspection, any

discrepancy was found.

(b)

6,000 flight cycles.Within 6,000 flight cycles after the rig of

the MCD was checked.

Do a HFEC or magnetic

particle inspection of cam

latch 1 and cam latch 2

for any cracks in accordance with Paragraph

3.B., Work Instructions

Step 8.a.3

Contact The Boeing Before further flight. -

Company for repair instructions and do the repair.

Any discrepancy found

during Condition 6 or

Condition 7 inspections.

(a) A reworked cam latch is defined as a cam latch that has been reworked within limits of CMM 52-32-03

and/or a Boeing ODA approved repair via FAA Form 8100-9 and has been HFEC or magnetic particle inspected, and has no crack(s) or gouge(s) in critical area(s).

(b) Discrepancy is defined as: Any broken, cracked, missing or gouged cam latches or latch pins, broken or

missing latch pin cross bolts, latch pin extension less than 0.89 inches or greater than 0.91 inches, or cam

latch lip deformation.

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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BOEING SERVICE BULLETIN 757-52A0091

ALERT ALERT
If an airplane has a non-Boeing modification or repair that affects a component or system also affected

by this service bulletin, the operator is responsible for obtaining appropriate regulatory agency approval

before incorporating this service bulletin.

G. Manpower

The table below shows an estimate of the task hours necessary to do the inspections and modifications

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.

Number of Per- Task Hours Elapsed Hours

sons

Task

Open Access 1 0.25 0.25

FIGURE 1 1 1.60 1.60

FIGURE 2 1 0.50 0.50

FIGURE 3 1 0.50 0.50

FIGURE 4 1 1.00(h) 1.00(h)

FIGURE 5 1 1.00 1.00

FIGURE 6 1(i) 0.50(a) (f) (i) 0.50(a) (f) (i)

FIGURE 7 1 0.10(b) (g) 0.10(b) (g)

FIGURE 8 1 0.60(c) 0.60(c)

FIGURE 9 1 0.10(d) 0.10(d)

FIGURE 10 - FIG- 2-3 48.0 20.0

URE 11

Close Access 1 0.25 0.25

TOTAL FOR EACH AIRPLANE (e) (e)

(a) Estimate is per cam latch requiring replacement.

(b) Estimate is per latch pin requiring replacement.

(c) Estimate is per cam latch requiring inspection.

(d) Estimate is per cam latch.

(e) Total time required may vary depending upon conditions found during inspections.

(f) Does not include time to match drill cam shaft.

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ALERT ALERT
Number of Per- Task Hours Elapsed Hours

sons

Task

(g) Does not include time to match drill latch pin

(h) Does not include NDI inspection time

(i) Cam latch 4 will require 2 hours and a second person to remove.

H. Weight and Balance Changes

Change in Moment

(Pound-Inches)

Change in Weight

Airplane (Pounds)

757-200CB Negligible Negligible

757-200PF Negligible Negligible

757-200 Special Negligible Negligible

Freighter

I. Electrical Load Data

Not changed.

J. References

1. Existing Data:

a. Boeing Service Related Problem (SRP) 757-SRP-52-0088

b. Component Maintenance Manual (CMM) 52-32-03, Repair 7-2.

c. Federal Aviation Administration (FAA) Notice of Proposed Rule Making (NPRM)

2011-NM-163-AD

d. Standard Overhaul Practices Manual (SOPM) 20-20-01

e. 757 Aircraft Maintenance Manual (AMM) 52-32-00

f. 757 Non-Destructive Testing (NDT) Manual Part 6, 51-00-12 or 51-00-21

2. Data Supplied with this Service Bulletin:

None.

3. Installation Drawings Used in the Preparation of this Service Bulletin:

Drawing Number Title

65-25326 DOOR INSTALLATION - MAIN CARGO

65-25339 LATCH MECHANISM INSTALLATION - MAIN CARGO DOOR

143N8750 SILL INSTL - LOWER, MAIN CARGO DOOR

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ALERT ALERT
Drawing Number Title

65-67872 LATCH PIN FITTING - ASSY

69-23438 CAM - LATCH MECHANISM CARGO DOOR

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:

Publication Chapter-Section

757 Illustrated Parts Catalog 52-32, 52-33

757 Component Maintenance Manual 52-32

757 Aircraft Maintenance Manual 52-32

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.

Repairs accomplished on cam latch(es) in accordance with CMM 52-32-03 are structurally

acceptable as Category A repairs as defined in 757-200 SRM 51-00-06, 757-200CB SRM 51-00-06

and 757-200PF SRM 51-00-06, therefore no supplemental inspections to the mandated damage

tolerance inspections contained in Paragraph 1.E., Compliance, Table 2, of this service bulletin,

are required.

L. Interchangeability and Intermixability of Parts

Accomplishment of this service bulletin does not affect interchangeability or intermixability of parts.

M. Software Accomplishment Summary

Not affected.

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ALERT ALERT
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ALERT ALERT

BLANK PAGE
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 inspections and modifications given in this service

bulletin.

C. Parts Necessary for Each Airplane

1. Kits/Parts

None.

2. Parts and Materials Supplied by the Operator

Part Number / QTY Name Existing Part Number Notes

Specification

BOLT, HEX HEAD, 160 KSI MIN NAS6603-24 (a) (b)

TENSILE, LONG THREAD, A286,

NONLOCKING

BACB30LM3-24 8

OR

BACB30LM3-22

OR

BACB30NF3-22

69-23438-2 1 Cam Latch 1 69-23438-2 (c)

143N8060-1 1 Cam Latch 2 143N8060-1 (c)

143N8027-2 1 Cam Latch 3 143N8027-2 (c)

69-23439-3 1 Cam Latch 4 69-23439-3 (c)

69-23439-4 1 Cam Latch 5 69-23439-4 (c)

143N8027-1 1 Cam Latch 6 143N8027-1 (c)

143N8060-2 1 Cam Latch 7 143N8060-2 (c)

69-23438-1 1 Cam Latch 8 69-23438-1 (c)

6-83137-2 8 Latch Pin 6-83137-2 (c)

(a) Refer to 757 Structural Repair Manual Chapter 51 for alternate fasteners.

(b) BACB30LM3-24 and NAS6603-24 used if 143N8157-2 Clip Assembly is installed.

(c) Part numbers and quantities necessary are based on inspection findings.

NOTE: Rubber Quicksetting Putty (G50673) is needed if the door rigging procedure per 757

AMM 52-32-00 20Sep2008 Revision or later is used.

3. Parts Modified and Reidentified

None.

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ALERT ALERT
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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ALERT ALERT
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:

– Linear dimensions are in inches

– Tolerance on linear dimensions, other than rivet and bolt edge margins, is plus

or minus 0.03 inch

– Tolerance on rivet and bolt edge margin is plus or minus 0.05 inch

– Angular tolerance is plus or minus 2 degrees

– Hole dimensions for standard solid rivets and fasteners are in Structural Repair

Manual (SRM) Chapter 51

– Torque Values:

— Values for structural fasteners are given in 757 Structural Repair Manual,

Chapter 51.

— Values for airframe maintenance tasks are included in Chapter 20 of 757

Airplane Maintenance Manual (AMM).

— Non-standard torque values for maintenance tasks are included in the

applicable installation step.

4. Use the approved fastener, process and 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. Clearance between fasteners and surrounding structures or mechanisms may be

minimal by design at some locations. Use caution when adjusting grip length of

fasteners and make sure no interference conditions exist after installation. Interference

between moving parts may be difficult to detect. Complete full cycle of mechanisms

to ensure no interference conditions exist.

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 procedures may be required.

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ALERT ALERT
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. The instructions in Paragraph 3.B., Work Instructions and the figures can include

operation of tools or test equipment. Boeing Engineering Tool Drawings, the Illustrated

Tool and Equipment Manual, and the Special Tool and Ground Handling Drawing

Index contain data on versions of the tools or test equipment that you can use. It is

permitted to use replaced tools. It is not permitted to use superseded tools.

11. 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.

12. Where the work instructions include installation of a kept part, a new or reworked

part with the same part number can be installed as an alternative to the kept part.

13. Damage found on cam latch(es) within the reworkable limits of CMM 52-32-03 can

be reworked in accordance with CMM 52-32-03.

14. A reworked cam latch is defined as a cam latch that has been reworked within the

limits of CMM 52-32-03 and/or a Boeing ODA approved repair via FAA Form 8100-9

and has been HFEC or magnetic particle inspected, and has no crack(s) or gouge(s)

in critical area(s).

15. Discrepancy is defined as: Any broken, cracked, missing or gouged cam latches or

latch pins, broken or missing latch pin cross bolts, latch pin extension less than 0.89

inches or greater than 0.91 inches, or cam latch lip deformation.

B. WORK INSTRUCTIONS

1. Initial (Pre-Rig Check) Inspections

a. Get access to the Main Cargo Door (MCD).

b. Do a general visual inspection for any broken cam latches, latch pins and latch pin cross bolts

and for any missing cam latches, latch pins and latch pin cross bolts in accordance with

FIGURE 9 .

c. Torque the cross bolts in the latch pins in accordance with FIGURE 2.

d. Measure the extension of the latch pins in accordance with FIGURE 3.

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e. Do a general visual inspection of all cam latches for lip deformation in accordance with FIGURE

1.

2. Condition 1:

One or more of the following is found:

– Broken or missing cam latch(es)

– Broken or missing latch pin(s)

– Broken or missing latch pin cross bolt(s)

a. Replace broken or missing cam latch(es) in accordance with FIGURE 6, replace broken and

missing latch pin(s) in accordance with FIGURE 7 and replace broken and missing latch pin

cross bolt(s) in accordance with FIGURE 5.

b. Do a detailed inspection of mating part(s) and immediately adjacent cam latches and latch

pins for any cracks, or any gouges in critical areas in accordance with FIGURE 8. Do all

applicable corrective actions as described in Condition 5.

c. Unless replaced with new or reworked parts, do a HFEC or magnetic particle inspection of

cam latch 1 and cam latch 2 for of cracks in critical areas in accordance with FIGURE 4. Do

all applicable corrective actions as described in Condition 5.

d. Check the rig of the Main Cargo Door in accordance with FIGURE 10 and FIGURE 11, and

replace all alloy steel cross bolts through the latch pins with CRES cross bolts in accordance

with FIGURE 5. If MCD is out of rig and cannot be adjusted in accordance with FIGURE 10

and FIGURE 11, rig the MCD. Refer to 757 AMM 52-32-00 Rev 20Sep2008 or later as an

accepted procedure for MCD rigging.

3. Condition 2:

The latch pin extension is less than 0.89 inches or greater than 0.91 inches:

a. Replace the discrepant latch pin in accordance with FIGURE 7.

b. Do a detailed inspection of the mating cam latch for any cracks, or gouges in critical areas in

accordance with FIGURE 8. Do all applicable corrective actions as described in Condition 5.

c. Do a general visual inspection for any broken cam latches, latch pins and latch pin cross bolts

and for any missing cam latches, latch pins and latch pin cross bolts in accordance with

FIGURE 9 . Do all applicable corrective actions as described in Condition 1.

d. Do a detailed inspection of the latch pin(s) and mating cam latch(es) for any cracks, or any

gouges in critical areas in accordance with FIGURE 1. Do all applicable corrective actions as

described in Condition 5.

e. Unless replaced with new or reworked parts, do a HFEC or magnetic particle inspection of

cam latch 1 and cam latch 2 for any cracks in critical areas in accordance with FIGURE 4. Do

all applicable corrective actions as described in Condition 5.

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f. Check the rig of the Main Cargo Door in accordance with FIGURE 10 and FIGURE 11, and

replace all alloy steel cross bolts through the latch pins with CRES cross bolts in accordance

with FIGURE 5. If MCD is out of rig and cannot be adjusted in accordance with FIGURE 10

and FIGURE 11, rig the MCD. Refer to 757 AMM 52-32-00 Rev 20Sep2008 or later as an

accepted procedure for MCD rigging.

NOTE: Rigging for the latch pin will require it to be installed properly with an extension of

0.90 +/- 0.01 inches. A latch pin with an original extension between 0.84 to 0.94

inches, with no cracks or gouges in critical areas and no other discrepancies may

be re-used by clocking the latch pin 90 degrees +/- 10 degrees from original position

and match drilling a new cross bolt hole that provides the correct latch pin extension.

Fill old cross bolt hole in pin with BMS 5-95 sealant and install pin with BMS 3-27

corrosion inhibiting compound.

4. Condition 3:

If a cam latch is found with lip deformation.

a. Do a detailed inspection of the discrepant cam latch and mating latch pin for any cracks, or

gouges in critical areas in accordance with FIGURE 1. Do all applicable corrective actions as

described in Condition 5.

b. Do a general visual inspection for any broken cam latches, latch pins and latch pin cross bolts

and for any missing cam latches, latch pins and latch pin cross bolts in accordance with

FIGURE 9. Do all applicable corrective actions as described in Condition 1.

c. Do a detailed inspection of the latch pin(s) and mating cam latch(es) for any cracks, or any

gouges in critical areas in accordance with FIGURE 1. Do all applicable corrective actions as

described in Condition 5.

d. Unless replaced with new or reworked parts, do a HFEC or magnetic particle inspection of

cam latch 1 and cam latch 2 for any cracks in critical areas in accordance with FIGURE 4. Do

all applicable corrective actions as described in Condition 5.

e. Check the rig of the Main Cargo Door in accordance with FIGURE 10 and FIGURE 11, and

replace all alloy steel cross bolts through the latch pins with CRES cross bolts in accordance

with FIGURE 5. If MCD is out of rig and cannot be adjusted in accordance with FIGURE 10

and FIGURE 11, rig the MCD. Refer to 757 AMM 52-32-00 Rev 20Sep2008 or later as an

accepted procedure for MCD rigging.

5. Condition 4:

No discrepancies found:

a. Do a general visual inspection for any broken and missing cam latches, latch pins and latch

pin cross bolts in accordance with FIGURE 9. Do all applicable corrective actions as described

in Condition 1.

b. Do a detailed inspection of the cam latches and latch pins for any cracks, or any gouges in

critical areas in accordance with FIGURE 1. Do all applicable corrective actions as described

in Condition 5.

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c. Unless replaced with new or reworked parts, do a HFEC or magnetic particle inspection of

cam latch 1 and cam latch 2 for any cracks in critical areas in accordance with FIGURE 4. Do

all applicable corrective actions as described in Condition 5.

d. Check the rig of the Main Cargo Door in accordance with FIGURE 10 and FIGURE 11, and

replace all alloy steel cross bolts through the latch pins with CRES cross bolts in accordance

with FIGURE 5. If MCD is out of rig and cannot be adjusted in accordance with FIGURE 10

and FIGURE 11, rig the MCD. Refer to 757 AMM 52-32-00 Rev 20Sep2008 or later as an

accepted procedure for MCD rigging.

6. Condition 5:

If the detailed, HFEC or magnetic particle inspections in Conditions 1 thru 4 reveal any of the

following:

– Cracked or gouged cam latch(es) in critical areas.

– Cracked or gouged latch pin(s) in critical areas.

a. Replace cracked or gouged cam latch(es) in accordance with FIGURE 6, replace cracked or

gouged latch pin(s) in accordance with FIGURE 7.

b. Do a detailed inspection of mating part(s) and immediately adjacent cam latches and latch

pins for any cracks or any gouges in critical areas in accordance with FIGURE 8. Do all

applicable corrective actions as described in Condition 5.

c. Unless replaced with new or reworked parts, do a HFEC or magnetic particle inspection of

cam latch 1 and cam latch 2 for any cracks in critical areas in accordance with FIGURE 4. Do

all applicable corrective actions as described in Condition 5.

d. Check the rig of the MCD in accordance with FIGURE 10 and FIGURE 11 and replace all

alloy steel cross bolts with CRES cross bolts in accordance with FIGURE 5. If MCD is out of

rig and cannot be adjusted in accordance with FIGURE 10 and FIGURE 11, rig the MCD.

Refer to 757 AMM 52-32-00 Rev 20Sep2008 or later as an accepted procedure for MCD

rigging.

7. Post Rig Check Repetitive Inspections.

a. Condition 6:

Airplanes that have accomplished all Table 1 requirements identified in Paragraph 1.E.,

Compliance, including rigging of the main cargo door in accordance with the original issue or

revision 1 of this service bulletin and no rigging adjustment of any latch pin or any latch pin

fitting was required, and during previous pre-rig check inspections there were no discrepancies

found:

(1) Do a general visual inspection for any broken or missing cam latches, latch pins and latch

pin Cross Bolt in accordance with FIGURE 9.

(2) Do a detailed inspection of the cam latches and latch pins for any cracks or any gouges

in critical areas in accordance with FIGURE 1.

(3) Do a HFEC or magnetic particle inspection of cam latch 1 and cam latch 2 for any cracks

in critical areas in accordance with FIGURE 4.

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(4) If any discrepancy is found during the Condition 6 inspections, contact The Boeing

Company for repair instructions and do the repair.

8. Post Rig Check Repetitive Inspections.

a. Condition 7:

Airplanes that have accomplished all Table 1 requirements identified in Paragraph 1.E.,

Compliance, including rigging of the main cargo door in accordance with the original issue or

revision 1 of this service bulletin and rigging adjustment of any latch pin or any latch pin fitting

was required, or during previous pre-rig check inspections there were any discrepancies found.

(1) Do a general visual inspection for any broken or missing cam latches, latch pins and latch

pin cross bolts in accordance with FIGURE 9.

(2) Do a detailed inspection of the cam latches and latch pins for any cracks or any gouges

in critical areas in accordance with FIGURE 1.

(3) Do a HFEC or magnetic particle inspection of cam latch 1 and cam latch 2 for any cracks

in critical areas in accordance with FIGURE 4.

(4) If any discrepancy is found during the Condition 7 inspections, contact The Boeing

Company for repair instructions and do the repair.

9. Put the airplane back to a serviceable condition.

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FIGURE 1: MAIN CARGO DOOR - CAM LATCHES AND LATCH PINS INSPECTION

(SHEET 1 OF 3)

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FIGURE 1: MAIN CARGO DOOR - CAM LATCHES AND LATCH PINS INSPECTION

(SHEET 2 OF 3)

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ALERT ALERT
The step numbers shown below agree with the numbers shown in the circle symbols in the figure. The QTY

numbers shown below are the number of parts necessary for this figure.

Step Task Name Identification Qty More Data

Detailed inspection

of the cam latch.(a)

(b)

1 Inspect Cam Latch 1 69-23438-2 1

Detailed inspection

of the cam latch.(a)

(b)

2 Inspect Cam Latch 2 143N8060-1 1

Detailed inspection

of the cam latch.(a)

(b)

3 Inspect Cam Latch 3 143N8027-2 1

Detailed inspection

of the cam latch.(a)

(b)

4 Inspect Cam Latch 4 69-23439-3 1

Detailed inspection

of the cam latch.(a)

(b)

5 Inspect Cam Latch 5 69-23439-4 1

Detailed inspection

of the cam latch.(a)

(b)

6 Inspect Cam Latch 6 143N8027-1 1

Detailed inspection

of the cam latch.(a)

(b)

7 Inspect Cam Latch 7 143N8060-2 1

Detailed inspection

of the cam latch.(a)

(b)

8 Inspect Cam Latch 8 69-23438-1 1

Detailed inspection

of the latch pin.(a)

9 Inspect Latch Pin 6-83137-2 8

(a) Look for cracks or gouges in critical areas.

(b) Do a general visual inspection for lip deformation.

FIGURE 1: MAIN CARGO DOOR - CAM LATCHES AND LATCH PINS INSPECTION

(SHEET 3 OF 3)

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FIGURE 2: MAIN CARGO DOOR - LATCH PIN CROSS BOLT TORQUE

(SHEET 1 OF 2)

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The step numbers shown below agree with the numbers shown in the circle symbols in the figure. The QTY

numbers shown below are the number of parts necessary for this figure.

Step Task Name Identification Qty More Data

1 Torque Cross Bolt - 8 (a)

(a) Make sure the latch pin cross bolt is capable of reaching a 15 pound-inch, +/- 1 pound-inch, torque from

the head side of the bolt and also the nut side if no nutplate is used. The 15 pound-inch, +/- 1 pound-inch,

torque value is approximately one-half of the installation torque and is used to give an indication of a

broken cross bolt.

FIGURE 2: MAIN CARGO DOOR - LATCH PIN CROSS BOLT TORQUE

(SHEET 2 OF 2)

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FIGURE 3: MAIN CARGO DOOR - LATCH PIN EXTENSION MEASUREMENT

(SHEET 1 OF 2)

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ALERT ALERT
The step numbers shown below agree with the numbers shown in the circle symbols in the figure. The QTY

numbers shown below are the number of parts necessary for this figure.

STEP TASK NAME IDENTIFICATION QTY MORE DATA

Make sure the latch

pin extends out 0.90

inch +/- 0.01 inch

from the wear plate.

1 Measure Latch Pin 6-83137-2 8

FIGURE 3: MAIN CARGO DOOR - LATCH PIN EXTENSION MEASUREMENT

(SHEET 2 OF 2)

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FIGURE 4: MAIN CARGO DOOR - CAM LATCH 1 AND CAM LATCH 2 INSPECTION

(SHEET 1 OF 2)

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ALERT ALERT
The step numbers shown below agree with the numbers shown in the circle symbols in the figure. The QTY

numbers shown below are the number of parts necessary for this figure.

STEP TASK NAME IDENTIFICATION QTY MORE DATA

1 Remove / Keep Cam Latch 1 69-23438-2 1

2 Remove / Keep Cam Latch 2 143N8060-1 1

Do a HFEC inspection of cam latch 1 for

cracks in accordance with 757 NDT Part 6,

51-00-12 or 51-00-21.(a) (b) (c)

3 Inspect Cam Latch 1 69-23438-2 1

Do a HFEC inspection of cam latch 2 for

cracks in accordance with 757 NDT Part 6,

51-00-12 or 51-00-21.(a) (b) (c)

Inspect Cam Latch 2 143N8060-1 1

4 Install (Kept) Cam Latch 1 69-23438-2 1

5 Install (Kept) Cam Latch 2 143N8060-1 1

(a) Use a 0.080 inch diameter or smaller HFEC probe. Set the HFEC instrument to operate between 50 KHz

and 75 KHz. If HFEC method indicates a crack, confirm the crack indication using magnetic particle inspection. Refer to SOPM 20-20-01 as an accepted procedure.

(b) An optional magnetic particle inspection can be used. Refer to SOPM 20-20-01 as an accepted procedure.

(c) HFEC crack indications can be confirmed using the magnetic particle inspection. If crack indications are

found with HFEC and could not be confirmed with magnetic particle inspection, the HFEC crack indication

is a non relevant indication due to chrome cracking.

FIGURE 4: MAIN CARGO DOOR - CAM LATCH 1 AND CAM LATCH 2 INSPECTION

(SHEET 2 OF 2)

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FIGURE 5: MAIN CARGO DOOR - LATCH PIN CROSS BOLT REPLACEMENT

(SHEET 1 OF 2)

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ALERT ALERT
The step numbers shown below agree with the numbers shown in the circle symbols in the figure. The QTY

numbers shown below are the number of parts necessary for this figure.

Step Task Name Identification Qty More Data

NAS6603-24 8 -

(BACB30NF3-22 optional)

1 Remove Latch Pin Cross Bolt

Install with BMS 3-

27 corrosion inhibiting material

BACB30LM3-24 8

(BACB30LM3-22 optional)

2 Install (New) Latch Pin Cross Bolt

FIGURE 5: MAIN CARGO DOOR - LATCH PIN CROSS BOLT REPLACEMENT

(SHEET 2 OF 2)

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FIGURE 6: MAIN CARGO DOOR - CAM LATCH REPLACEMENT

(SHEET 1 OF 3)

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FIGURE 6: MAIN CARGO DOOR - CAM LATCH REPLACEMENT

(SHEET 2 OF 3)

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ALERT ALERT
The step numbers shown below agree with the numbers shown in the circle symbols in the figure. The QTY

numbers shown below are the number of parts necessary for this figure.

Step Task Name Identification Qty More Data

1 Remove Cam Latch 1 69-23438-2 1 (a)

Remove Cam Latch 2 143N8060-1 1 (a)

Remove Cam Latch 3 143N8027-2 1 (a)

(a) Gusset must be

removed to allow removal of cam latch

number 4.

Remove Cam Latch 4 69-23439-3 1

Remove Cam Latch 5 69-23439-4 1 (a)

Remove Cam Latch 6 143N8027-1 1 (a)

Remove Cam Latch 7 143N8060-2 1 (a)

Remove Cam Latch 8 69-23438-1 1 (a)

2 Install (New) Cam Latch 1 69-23438-2 1 (a) (b) (d)

Install (New) Cam Latch 2 143N8060-1 1 (a) (b) (c) (d)

Install (New) Cam Latch 3 143N8027-2 1 (a) (b) (d)

(a) (b) (d) Gusset

must be removed to

allow installation of

cam latch number 4.

Install (New) Cam Latch 4 69-23439-3 1

Install (New) Cam Latch 5 69-23439-4 1 (a) (b) (d)

Install (New) Cam Latch 6 143N8027-1 1 (a) (b) (d)

Install (New) Cam Latch 7 143N8060-2 1 (a) (b) (c) (d)

Install (New) Cam Latch 8 69-23438-1 1 (a) (b) (d)

(a) Part numbers and quantities necessary are based on inspection findings.

(b) Use the original removed cam latch as a pattern/template to locate new cross bolt holes. Match hole angularity from existing cam latch.

(c) Cam latch number 2 and cam latch number 7 only have two cross bolt holes.

(d) It is acceptable to install a reworked Cam Latch with the same part number instead of a new part.

FIGURE 6: MAIN CARGO DOOR - CAM LATCH REPLACEMENT

(SHEET 3 OF 3)

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FIGURE 7: MAIN CARGO DOOR - LATCH PIN REPLACEMENT

(SHEET 1 OF 2)

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ALERT ALERT
The step numbers shown below agree with the numbers shown in the circle symbols in the figure. The QTY

numbers shown below are the number of parts necessary for this figure.

STEP TASK NAME IDENTIFICATION QTY MORE DATA

1 Remove Latch Pin 6-83137-2 - -

Install latch pin wet with BMS 3-27

corrosion inhibiting material on

faying surfaces. Make sure the

latch pin extends out 0.90 inch +/-

0.01 inch from the wear plate.

2 Install (New) Latch Pin 6-83137-2 -

FIGURE 7: MAIN CARGO DOOR - LATCH PIN REPLACEMENT

(SHEET 2 OF 2)

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FIGURE 8: MAIN CARGO DOOR - CAM LATCH REMOVAL AND INSPECTION

(SHEET 1 OF 3)

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FIGURE 8: MAIN CARGO DOOR - CAM LATCH REMOVAL AND INSPECTION

(SHEET 2 OF 3)

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ALERT ALERT
The step numbers shown below agree with the numbers shown in the circle symbols in the figure. The QTY

numbers shown below are the number of parts necessary for this figure.

Step Task Name Identification Qty More Data

1 Remove / Keep Cam Latch 1 69-23438-2 1 (a) (b)

Remove / Keep Cam Latch 2 143N8060-1 1 (a) (b)

Remove / Keep Cam Latch 3 143N8027-2 1 (a) (b)

Remove / Keep Cam Latch 4 69-23439-3 1 (a) (b) (c)

Remove / Keep Cam Latch 5 69-23439-4 1 (a) (b)

Remove / Keep Cam Latch 6 143N8027-1 1 (a) (b)

Remove / Keep Cam Latch 7 143N8060-2 1 (a) (b)

Remove / Keep Cam Latch 8 69-23438-1 1 (a) (b)

Detailed inspection

of the cam latch for

cracks or gouges in

critical areas. (d)

2 Inspect Cam Latch - -

3 Install (Kept) Cam Latch 1 69-23438-2 1 (a) (b) (e)

Install (Kept) Cam Latch 2 143N8060-1 1 (a) (b) (e)

Install (Kept) Cam Latch 3 143N8027-2 1 (a) (b) (e)

Install (Kept) Cam Latch 4 69-23439-3 1 (a) (b) (e)

Install (Kept) Cam Latch 5 69-23439-4 1 (a) (b) (e)

Install (Kept) Cam Latch 6 143N8027-1 1 (a) (b) (e)

Install (Kept) Cam Latch 7 143N8060-2 1 (a) (b) (e)

Install (Kept) Cam Latch 8 69-23438-1 1 (a) (b) (e)

Detailed inspection

of the latch pin for

cracks or gouges in

critical areas.

4 Inspect Latch Pin 6-83137-2 8

(a) It is important to identify the Cam Latch part locations to ensure the parts are re-installed in correct locations.

Cam latches installed incorrectly may seriously compromise proper door operation.

(b) Part numbers and quantities necessary are based on inspection findings.

(c) Gusset must be removed to allow removal of cam latch number 4.

(d) Only inspect removed cam latch(es).

(e) Do not install kept cam latch if cracked or gouged in critical areas.

FIGURE 8: MAIN CARGO DOOR - CAM LATCH REMOVAL AND INSPECTION

(SHEET 3 OF 3)

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Revision 1 December 19, 2014 757-52A0091

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BOEING SERVICE BULLETIN 757-52A0091

ALERT ALERT
FIGURE 9: MAIN CARGO DOOR - CAM LATCHES, LATCH PINS AND LATCH PIN CROSS BOLTS

INSPECTION

(SHEET 1 OF 2)

Export Controlled ECCN: 9E991 - BOEING

PROPRIETARY - Copyright © Unpublished

Work - See page 1 for details.

Original Issue: March 09, 2010

Revision 1 December 19, 2014 757-52A0091

56 of 62

BOEING SERVICE BULLETIN 757-52A0091

ALERT ALERT
The step numbers shown below agree with the numbers shown in the circle symbols in the figure. The QTY

numbers shown below are the number of parts necessary for this figure.

Step Task Name Identification Qty More Data

General visual inspection of the cam

latch.(a)

1 Inspect Cam Latch 1 69-23438-2 1

General visual inspection of the cam

latch.(a)

Inspect Cam Latch 2 143N8060-1 1

General visual inspection of the cam

latch.(a)

Inspect Cam Latch 3 143N8027-2 1

General visual inspection of the cam

latch.(a)

Inspect Cam Latch 4 69-23439-3 1

General visual inspection of the cam

latch.(a)

Inspect Cam Latch 5 69-23439-4 1

General visual inspection of the cam

latch.(a)

Inspect Cam Latch 6 143N8027-1 1

General visual inspection of the cam

latch.(a)

Inspect Cam Latch 7 143N8060-2 1

General visual inspection of the cam

latch.(a)

Inspect Cam Latch 8 69-23438-1 1

General visual inspection of the latch

pins.(a)

2 Inspect Latch Pin 6-83137-2 8

General visual inspection of the latch

pin cross bolts.(a)

3 Inspect Cross Bolt - 8

(a) Inspect for broken parts. Also inspect for missing parts.

FIGURE 9: MAIN CARGO DOOR - CAM LATCHES, LATCH PINS AND LATCH PIN CROSS BOLTS

INSPECTION

(SHEET 2 OF 2)

Export Controlled ECCN: 9E991 - BOEING

PROPRIETARY - Copyright © Unpublished

Work - See page 1 for details.

Original Issue: March 09, 2010

Revision 1 December 19, 2014 757-52A0091

57 of 62

BOEING SERVICE BULLETIN 757-52A0091

ALERT ALERT
FIGURE 10: MAIN CARGO DOOR - CAM LATCH AND LATCH PIN RIGGING

(SHEET 1 OF 3)

Export Controlled ECCN: 9E991 - BOEING

PROPRIETARY - Copyright © Unpublished

Work - See page 1 for details.

Original Issue: March 09, 2010

Revision 1 December 19, 2014 757-52A0091

58 of 62

BOEING SERVICE BULLETIN 757-52A0091

ALERT ALERT
FIGURE 10: MAIN CARGO DOOR - CAM LATCH AND LATCH PIN RIGGING

(SHEET 2 OF 3)

Export Controlled ECCN: 9E991 - BOEING

PROPRIETARY - Copyright © Unpublished

Work - See page 1 for details.

Original Issue: March 09, 2010

Revision 1 December 19, 2014 757-52A0091

59 of 62

BOEING SERVICE BULLETIN 757-52A0091

ALERT ALERT
The step numbers shown below agree with the numbers shown in the circle symbols in the figure. The QTY

numbers shown below are the number of parts necessary for this figure.

Step Task Name Identification Qty More Data

1 Measure Cam Latch - 8 (a) (b)

Measure Latch Pin 6-83137-2 8 (a) (b)

Measure Latch Pin Fitting - 8 (c)

(a) During rigging procedure the latch pin is not to contact the cam latch in any direction.

(b) Wrap a single layer of 0.002 inch thick shim stock around latch pins 1 and 8. Use thin tape to keep shim

in place. With latch pins 1 and 8 engaging their respective cam latches, and with latch pins 2 through 7

not contacting their respective cam latches in any direction, adjust if required, latch pin fittings 2 through

7 such that latch pins 2 through 7 axial centerlines and their respective cam latch axial centerlines are

within the tolerance shown.

(c) Adjust latch pin fittings by moving fitting on serrations and by adjusting shim thickness. On the two forward

and two aft cam latches the Latch Pin Fitting/Cam Latch gap is 0.14 +/- 0.01 inch. On the four center cam

latches the Latch Pin Fitting/Cam Latch gap is 0.08 +/- 0.01 inch. Make sure the maximum allowed shim

thickness of 0.20 inch is not exceeded.

FIGURE 10: MAIN CARGO DOOR - CAM LATCH AND LATCH PIN RIGGING

(SHEET 3 OF 3)

Export Controlled ECCN: 9E991 - BOEING

PROPRIETARY - Copyright © Unpublished

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Original Issue: March 09, 2010

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BOEING SERVICE BULLETIN 757-52A0091

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FIGURE 11: MAIN CARGO DOOR - MAIN CARGO DOOR EDGE FLUSHNESS MEASUREMENT

(SHEET 1 OF 2)

Export Controlled ECCN: 9E991 - BOEING

PROPRIETARY - Copyright © Unpublished

Work - See page 1 for details.

Original Issue: March 09, 2010

Revision 1 December 19, 2014 757-52A0091

61 of 62

BOEING SERVICE BULLETIN 757-52A0091

ALERT ALERT
The step numbers shown below agree with the numbers shown in the circle symbols in the figure. The QTY

numbers shown below are the number of parts necessary for this figure.

STEP TASK NAME IDENTIFICATION QTY MORE DATA

Hold scale 90 degrees to door edge.

Make sure the MCD lower edge and

lower corner flushness are within

the tolerance shown.

1 Measure Main Cargo Door - -

FIGURE 11: MAIN CARGO DOOR - MAIN CARGO DOOR EDGE FLUSHNESS MEASUREMENT

(SHEET 2 OF 2)

Export Controlled ECCN: 9E991 - BOEING

PROPRIETARY - Copyright © Unpublished

Work - See page 1 for details.

Original Issue: March 09, 2010

Revision 1 December 19, 2014 757-52A0091

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BOEING SERVICE BULLETIN 757-52A0091

ALERT ALERT