Commercial 

Airplanes 777

Service Bulletin

ALERT

Number: 777-53A0043

Original Issue: November 09, 2011

ATA System: 5315 5335 5355

SUBJECT: FUSELAGE - Skin Panels - Skin Lap Splice Inspection for Fatigue Cracks at Maskant

Trim Scribe Lines

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Table of Contents

Summary ...................................................... 5

1. PLANNING INFORMATION ........................................ 9

A. Effectivity ................................................ 9

1. Airplanes ............................................. 9

2. Spares Affected . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10

B. Concurrent Requirements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10

C. Reason . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11

D. Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11

E. Compliance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12

F. Approval . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13

G. Manpower . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13

H. Weight and Balance Changes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14

I. Electrical Load Data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14

J. References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14

1. Existing Data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14

2. Data supplied with this Service Bulletin . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15

3. Installation Drawings Used in the Preparation of this Service Bulletin . . . . . . . . . . . . 15

K. Publications Affected . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15

L. Interchangeability and Intermixability of Parts . . . . . . . . . . . . . . . . . . . . . . . . . . . 15

2. MATERIAL INFORMATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17

A. Material - Price and Availability . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17

B. Industry Support Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17

C. Parts Necessary For Each Airplane . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17

1. Kits/Parts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17

2. Parts and Materials Supplied by the Operator . . . . . . . . . . . . . . . . . . . . . . . . 17

3. Parts Modified and Reidentified . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17

4. Parts Removed and Not Replaced . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17

D. Parts Necessary to Change Spares . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17

E. Special Tooling - Price and Availability . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17

F. Special Tooling Necessary to do this Service Bulletin . . . . . . . . . . . . . . . . . . . . . . . 17

3. ACCOMPLISHMENT INSTRUCTIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19

A. GENERAL INFORMATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19

B. WORK INSTRUCTIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20

FIGURE 1: AFFECTED SECTION 41 LAP SPLICES . . . . . . . . . . . . . . . . . . . . . . . . . . . 22

FIGURE 2: AFFECTED SECTION 43 AND SECTION 44 LAP SPLICES [Group 1] . . . . . . . . . . . 24

FIGURE 3: PHASED ARRAY ULTRASONIC LAP SPLICE INSPECTION . . . . . . . . . . . . . . . . 26

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Commercial 

Airplanes 777

Service Bulletin

ALERT

Summary Number: 777-53A0043

Original Issue: November 09, 2011

ATA System: 5315 5335 5355

SUBJECT: FUSELAGE - Skin Panels - Skin Lap Splice Inspection for Fatigue Cracks at Maskant

Trim Scribe Lines

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

This service bulletin gives instructions for the inspection and repair of fatigue cracks at scribe lines in the fuselage

skin at certain lap joints in Section 41, Section 43 and Section 44. Fatigue cracks can develop in the skin at

locations where scribe lines were made during production. Fatigue cracks in the skin that remain undetected

could grow large and cause sudden decompression and the inability to sustain limit load.

On affected airplanes, scribe lines may have been inadvertently made in the overlapped skin in lap joints if a

sharp tool was used to remove the maskant from the clad aluminum skin panels during assembly of the affected

lap joints. During the 777 fatigue test, lap joint cracks were found, and analysis indicated that those cracks

initiated at scribe lines that were made during production when maskant was removed from the affected skin

panels.

Accomplishment of the inspections shown in this service bulletin will help make sure that fatigue cracks that can

form in the fuselage skin at maskant trim scribe lines are found and repaired before they can become large and

cause sudden loss of cabin pressure.

Boeing Service Related Problem (SRP) 777-SRP-53-0165 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

AD Related Yes Paragraph 1.E., Compliance

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

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Planning Data Affected Reference

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

Publications Affected No 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 Material No

Paragraph 2.F., Special Tooling Necessary to

do this Service Bulletin

Special Tooling Required No

ACTION (PRR 62777-56RS)

Do external ultrasonic inspections at certain skin lap splices for cracks in the overlapped skin. On Group 1

airplanes, affected lap splices are in Section 41, 43 and 44. On Group 2 airplanes, affected lap splices are only

in Section 41. Where cracks are found, repair in accordance with this service bulletin. Where no cracks are

found, repeat the inspection in accordance with this service bulletin.

EFFECTIVITY

777-200 and 777-300 Airplanes. Refer to Paragraph 1.A.1., Airplanes, for the list of affected airplanes.

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.

Refer to Paragraph 1.E., Compliance.

INDUSTRY SUPPORT INFORMATION

Boeing warranty remedies are available for airplanes in warranty as of October 25, 2001. Please refer to

Paragraph 2.B., Industry Support Information.

MANPOWER

Airplanes Total Task Hours Elapsed Hours

Group 1 126.0 31.5

Group 2 50.0 12.5

Refer to Paragraph 1.G., Manpower.

MATERIAL INFORMATION

None.

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Commercial 

Airplanes 777

Service Bulletin

ALERT

Number: 777-53A0043

Original Issue: November 09, 2011

ATA System: 5315 5335 5355

SUBJECT: FUSELAGE - Skin Panels - Skin Lap Splice Inspection for Fatigue Cracks at Maskant

Trim Scribe Lines

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 D624W001 Part 3 for Airplane Variable Number, Line Number, and

Serial Number data.

This service bulletin is for the airplanes shown below. Refer to PRR 62777-56RS for data about

this change.

GROUP CONFIGURATION DESCRIPTION

1 - All 777-200 airplanes line number 1 - 75.

2 - All 777-200 and 777-300 airplanes line number 76 - 104.

Airplane Models:

777-200, 777-300

Variable Number Group

WA001 - WA017 1

WA076 - WA080 1

WA086 - WA089 1

WA090 - WA092 2

WA101 - WA104 1

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Variable Number Group

WA116 - WA119 1

WA131 - WA136 1

WA137 2

WA171 - WA175 1

WA196 - WA198 1

WA206 1

WA207 2

WA221 1

WA222 2

WB001 - WB008 1

WB009 2

WB051 - WB056 1

WB057 - WB062 2

WB101 - WB103 1

WB104 2

WB121 - WB122 1

WB131 - WB132 1

WB151 1

WB152 - WB153 2

WB161 - WB162 1

WB163 - WB164 2

WB181 1

WB182 - WB184 2

WB271 2

WB276 - WB279 2

WB501 - WB502 2

WB531 2

2. Spares Affected

None.

B. Concurrent Requirements

None.

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C. Reason

This service bulletin gives instructions for the inspection and repair of fatigue cracks at scribe lines in

the fuselage skin at certain lap joints in Section 41, Section 43 and Section 44. Fatigue cracks can

develop in the skin at locations where scribe lines were made during production. Fatigue cracks in the

skin that remain undetected could grow large and cause sudden decompression and the inability to

sustain limit load.

On affected airplanes, scribe lines may have been inadvertently made in the overlapped skin in lap

joints if a sharp tool was used to remove the maskant from the clad aluminum skin panels during

assembly of the affected lap joints. During the 777 fatigue test, lap joint cracks were found, and analysis

indicated that those cracks initiated at scribe lines that were made during production when maskant

was removed from the affected skin panels.

Accomplishment of the inspections shown in this service bulletin will help make sure that fatigue cracks

that can form in the fuselage skin at maskant trim scribe lines are found and repaired before they can

become large and cause sudden loss of cabin pressure.

Boeing Service Related Problem (SRP) 777-SRP-53-0165 is related to this service bulletin.

D. Description

Do external ultrasonic inspections at certain skin lap splices for cracks in the overlapped skin. On Group

1 airplanes, affected lap splices are in Section 41, 43 and 44. On Group 2 airplanes, affected lap splices

are only in Section 41. Where cracks are found, repair in accordance with this service bulletin. Where

no cracks are found, repeat the inspection in accordance with this service bulletin.

NOTE: This service bulletin is similar to Boeing Service Bulletin 777-53A0054, "Fuselage - - Body

Station 132.5 to Body Station 2150 - External Inspection of the Fuselage Skin for External

Scribe Lines, " but it does not replace Service Bulletin 777-53A0054. The cause of the scribe

lines, the specific location of the scribe lines, and affected airplanes are different in this service

bulletin than in Service Bulletin 777-53A0054.

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

Group 1:

Affected Maintenance Zones

Model Zone

117, 118, 121, 122, 123, 124, 125, 126, 221,

222, 223, 224, 231, 232, 233, 234, 243, 244

777-200

Group 2:

Affected Maintenance Zones

Model Zone

777-200, 777-300 117, 118, 121, 122, 123, 124, 221, 222, 223, 224

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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.

Group 1:

Table 1:Lap Splice Inspection - Section 41, 43 and 44

Repeat Interval

(Not to Exceed)

Compliance Time (Whichever

Occurs Later)

Condition Action

Within 24 -

months after

the original issue date on

this service

bulletin.

Before 34,000

total flight-cycles.

Do external phased-array ultrasonic

inspections of certain fuselage skin

lap splices in Section 41, Section

43, and Section 44 for cracks in accordance with Paragraph 3.A.,

General Information and Paragraph

3.B., Work Instructions, PART 1.

All Airplanes

Within 4,200 - 4,200 flight-cycles.

flight-cycles after the previous inspection.

Do external phased-array ultrasonic

inspections of any affected, unrepaired lap splices for cracks in accordance with Paragraph 3.A., General

Information and Paragraph 3.B.,

Work Instructions, PART 1.

Where no crack is

found.

Repair in accordance with Para- Before further flight. -

graph 3.A., General Information and

Paragraph 3.B., Work Instructions,

PART 2. (a)

Where any crack is

found.

(a) No more inspections are necessary per this service bulletin in the repaired area. Do post-repair inspections

in accordance with the applicable Structural Repair Manual, or other approved data.

Group 2:

Table 2: Section 41 Lap Splice Inspection

Repeat Interval

(Not to Exceed)

Compliance Time (Whichever

Occurs Later)

Condition Action

Within 24 -

months after

the original issue date on

this service

bulletin.

Before 34,000

total flight-cycles.

Do external phased-array ultrasonic

inspections of certain fuselage skin

lap splices in Section 41 for cracks

in accordance with Paragraph 3.A.,

General Information and Paragraph

3.B., Work Instructions, PART 1.

All Airplanes

Within 4,200 - 4,200 flight-cycles.

flight-cycles after the previous inspection.

Do external phased-array ultrasonic

inspections of any affected, unrepaired lap splices in accordance with

Paragraph 3.A., General Information

and Paragraph 3.B., Work Instructions, PART 1.

Where no crack is

found.

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Group 2:

Table 2: Section 41 Lap Splice Inspection

Repeat Interval

(Not to Exceed)

Compliance Time (Whichever

Occurs Later)

Condition Action

Repair crack in accordance with Before further flight. -

Paragraph 3.A., General Information

and Paragraph 3.B., Work Instructions, PART 2. (a)

Where any crack is

found.

(a) No more inspections are necessary per this service bulletin in the repaired area. Do post-repair inspections

in accordance with the applicable Structural Repair Manual, or other approved data.

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.

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:

Table 1 - Phased Array Ultrasonic Inspection Method

Task Number of Persons Task Hours Elapsed Hours

Prepare 4 28.00 7.00

Inspect Section 41 4 39.00 9.75

(Figure 1 and Figure

3)

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Group 1:

Table 1 - Phased Array Ultrasonic Inspection Method

Task Number of Persons Task Hours Elapsed Hours

Inspect Section 43 4 59.00 14.75

and Section 44 (Figure 2 and Figure 3)

TOTAL FOR EACH AIRPLANE 126.00 31.50

Group 2:

Table 2 - Phased Array Ultrasonic Inspection Method

Task Number of Persons Task Hours Elapsed Hours

Prepare 4 11.00 2.75

Inspect Section 41 4 39.00 9.75

(Figure 1 and Figure

3)

TOTAL FOR EACH AIRPLANE 50.00 12.50

NOTE: More time will be necessary for repairs if cracks are found.

H. Weight and Balance Changes

None.

I. Electrical Load Data

Not changed.

J. References

1. Existing Data

a. Engineering Change Memo PRR 62777-56RS

b. Boeing Service Bulletin 777-53A0054

c. Boeing Service Letter 777-SL-51-013

d. Boeing Service Related Problem (SRP) 777-SRP-53-0165

e. Service Bulletin Index D624W001

f. 777 Aircraft Maintenance Manual (AMM) 51-21-01, 51-21-10, 51-31-01

g. 777 Non-Destructive Testing (NDT) Manual Part 4, 53-00-04

h. 777-200 Structural Repair Manual (SRM) 53-00-01

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i. 777-300 Structural Repair Manual (SRM) 53-00-01

2. Data supplied with this Service Bulletin

None.

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

None.

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 but no new DTIs are necessary.

L. Interchangeability and Intermixability of Parts

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

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2. MATERIAL INFORMATION

A. Material - Price and Availability

None.

B. Industry Support Information

Boeing warranty remedies are available for 777 airplanes in warranty as of October 25, 2001. For

inspection task hour reimbursement for airplanes in warranty as of that date, send a warranty claim to

Boeing Commercial Airplanes Group - Warranties. If the condition described in this service bulletin is

found during the inspection for airplanes in warranty as of that date and additional task hours are

required, send a warranty claim to Boeing Commercial Airplanes Group - Warranties. Please refer to

this service bulletin number and reference the airplane variable numbers in your purchase order.

C. Parts Necessary For Each Airplane

1. Kits/Parts

None.

2. Parts and Materials Supplied by the Operator

None.

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. 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

4. Use the approved fastener and process material substitutions in accordance with

SRM Chapter 51.

5. If the length of any fastener specified in this service bulletin does not meet installation

standards given in SRM Chapter 51, then a fastener of the same specification, or

an approved substitute, with a length which meets the installation standards given

in SRM Chapter 51 may be used. In addition, washers may be installed for fastener

grip length in accordance with SRM Chapter 51.

6. 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.

7. Boeing Service Letter 777-SL-51-013, Damage Reporting and Repair Plan/Design

Guidelines, is an acceptable procedure to request information from Boeing for

additional structural repair instructions. The Service Letter describes what information

must be provided to Boeing before a structural repair can be provided.

8. 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.

9. If it is necessary to remove more parts for access, you can remove those parts. If

you can get access without removing identified parts, it is not necessary to remove

all of the identified parts. Jacking and shoring limitations must be observed.

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B. WORK INSTRUCTIONS

1. Group 1:

Do the inspections in PART 1 at the time given in Paragraph 1.E., Compliance, Table 1.

2. Group 2:

Do the inspections in PART 1 at the time given in Paragraph 1.E., Compliance, Table 2.

PART 1 - EXTERNAL PHASED ARRAY ULTRASONIC INSPECTION

1. Get external access to the affected fuselage skin lap splices in Section 41. Affected Section 41

lap splices are shown in FIGURE 1.

NOTE: A fillet seal of BMS 5-142 was applied to the fuselage skin lap joints in Section 41 during

production. Any fillet seals that are wider than 0.3 inch must be removed (using approved

methods) before accomplishing the phased-array ultrasonic inspections in this service

bulletin. Refer to 777 AMM 51-31-01 as an accepted sealant removal procedure. After

inspection, reapplication of any removed fillet seal is optional.

2. Group 1:

Get external access to the affected fuselage skin lap splices in Section 43 and Section 44. Affected

Section 43 and Section 44 lap splices are shown in FIGURE 2.

3. Do an external phased array ultrasonic inspection of affected lap joints for cracks in the overlapped

skin in accordance with FIGURE 3.

NOTE: 1. The phased array ultrasonic inspection method does not require paint removal,

and only requires removal of fillet seals that are wider than 0.3 inch. (Fillet seals

were only applied during production to the lap splices in Section 41.)

2. Inspections at scribe lines are not required in lap splice areas where a repair

exists that has a minimum of three rows of fasteners above and below the lap

splice scribe line inspection location.

3. If a repair blocks the inspections required by this service bulletin and the repair

does not have a minimum of three rows of fasteners above and below the lap

splice scribe line inspection location, remove the repair and conduct the

inspections required by this service bulletin. After the inspection is complete,

install an approved repair that has a minimum of three rows of fasteners above

and below the lap splice scribe line inspection location.

4. If a crack is found, repair before further flight in accordance with PART 2.

NOTE: No more inspections are necessary in accordance with this service bulletin in repaired

areas, however do post-repair inspections in accordance with the applicable structural

repair manual or other approved repair method.

5. Group 1:

If no cracks are found, put the airplane back to a serviceable condition. In any affected areas that

have not been repaired, do the inspections in PART 1 at the time given in Paragraph 1.E.,

Compliance, Table 1.

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6. Group 2:

If no cracks are found, put the airplane back to a serviceable condition. In any affected areas that

have not been repaired, do the inspections in PART 1 at the time given in Paragraph 1.E.,

Compliance, Table 2.

PART 2 - REPAIR

1. Repair any crack that is found. Install a repair in accordance with 777-200 SRM 53-00-01 Repair

16 or 777-300 SRM 53-00-01 Repair 16 or other approved methods.

NOTE: After repair in accordance with the structural repair manual, no more inspections are

necessary per this service bulletin in the repaired area. Do post-repair inspections in

accordance with the structural repair manual or other approved methods.

2. Group 1:

Put the airplane back to a serviceable condition. In any affected areas that have not been repaired,

do the inspections in PART 1 again at the time given in Paragraph 1.E., Compliance, Table 1.

3. Group 2:

Put the airplane back to a serviceable condition. In any affected areas that have not been repaired,

do the inspections in PART 1 again at the time given in Paragraph 1.E., Compliance, Table 2.

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FIGURE 1: AFFECTED SECTION 41 LAP SPLICES

(SHEET 1 OF 2)

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FIGURE 1: AFFECTED SECTION 41 LAP SPLICES

(SHEET 2 OF 2)

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This Figure applies only to: Group 1.

FIGURE 2: AFFECTED SECTION 43 AND SECTION 44 LAP SPLICES

(SHEET 1 OF 2)

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FIGURE 2: AFFECTED SECTION 43 AND SECTION 44 LAP SPLICES

(SHEET 2 OF 2)

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FIGURE 3: PHASED ARRAY ULTRASONIC LAP SPLICE INSPECTION

(SHEET 1 OF 3)

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FIGURE 3: PHASED ARRAY ULTRASONIC LAP SPLICE INSPECTION

(SHEET 2 OF 3)

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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 each affected lap splice location.

STEP TASK NAME IDENTIFICATION QTY MORE DATA

Use the external

phased-array ultrasonic inspection

method in accordance with 777 NDT

Part 4, 53-00-04.

Fuselage Skin Lap - -

Splice

1 Inspect

FIGURE 3: PHASED ARRAY ULTRASONIC LAP SPLICE INSPECTION

(SHEET 3 OF 3)

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