# Boeing Alert Service Bulletin 777-78A0070: No revision named

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- Document: [Boeing Alert Service Bulletin 777-78A0070](https://openairdocs.org/service-documents/boeing/777-78a0070.md)
- Title as filed: Boeing Service Bulletin 
- Pages: 22
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## Text

Some pages are OCR from a scan. OCR can misread letters and numbers. Each page's text from the PDF; open the PDF at a page with #page=N.

### Page 1

Commercial        
Airplane
Group 
 777
Service Bulletin
ALERT
Number: 777-78A0070
Date: November 20, 2008
ATA System: 7831
SUBJECT: EXHAUST (GE90) - Thrust Reverser System - GE Scavenge Tube Interference with
Thrust Reverser Insulation Blanket Bolt - Replacement
Export of this technology is controlled under the United States Export Administration Regulations (EAR) (15
CFR 730-774). An export license may be required before it is used for development, production or use by foreign
persons from specific countries. The controller of this data has the individual responsibility to abide by all export
laws.
9E991ECCN:
BOEING PROPRIETARY, CONFIDENTIAL, AND/OR TRADE SECRET
Copyright © 2008 The Boeing Company
Unpublished Work - All Rights Reserved
Boeing claims copyright in each page of this document only to the extent that the page contains copyrightable
subject matter. Boeing also claims copyright in this document as a compilation and/or collective work.
This document includes proprietary information owned by The Boeing Company and/or one or more third parties.
Treatment of the document and the information it contains is governed by contract with Boeing. For more
information, contact The Boeing Company, P .O. Box 3707, Seattle, Washington 98124.
Boeing, the Boeing signature, the Boeing symbol, 707, 717, 727, 737, 747, 757, 767, 777, 787, Dreamliner,
BBJ, DC-8, DC-9, DC-10, MD-10, MD-11, MD-80, MD-88, MD-90, and the Boeing livery are all trademarks
owned by The Boeing Company; and no trademark license is granted in connection with this document unless
provided in writing by Boeing.
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2.0

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Table of Contents
Summary ..................................................... 5
1. PLANNING INFORMATION ......................................... 9
A. Effectivity ................................................ 9
1. Airplanes ............................................. 9
2. Spares Affected ........................................ 1 0
B. Concurrent Requirements ...................................... 1 0
C. Reason ................................................ 1 0
D. Description .............................................. 1 1
E. Compliance .............................................. 1 1
F . Approval ............................................... 1 1
G. Manpower .............................................. 1 1
H. Weight and Balance Changes .................................... 1 2
I. Electrical Load Data ......................................... 1 2
J. References .............................................. 1 2
1. Existing Data .......................................... 1 2
2. Data supplied with this Service Bulletin ............................ 1 2
3. Installation Drawings Used in the Preparation of this Service Bulletin ............ 1 2
K. Publications Affected ......................................... 1 3
L. Interchangeability and Intermixability of Parts ........................... 1 3
2. MATERIAL INFORMATION ........................................ 1 5
A. Material - Price and Availability ................................... 1 5
B. Industry Support Information .................................... 1 6
C. Parts Necessary For Each Airplane ................................. 1 6
1. Kits/Parts ............................................ 1 6
2. Parts and Materials Supplied by the Operator ........................ 1 6
3. Parts Modified and Reidentified ................................ 1 6
4. Parts Removed and Not Replaced .............................. 1 7
D. Parts Necessary to Change Spares ................................. 1 7
E. Special Tooling - Price and Availability ............................... 1 7
F . Special Tooling Necessary to do this Service Bulletin ....................... 1 7
3. ACCOMPLISHMENT INSTRUCTIONS .................................. 1 9
A. GENERAL INFORMATION ..................................... 1 9
B. WORK INSTRUCTIONS ....................................... 1 9
FIGURE 1: THRUST REVERSER - AFT COWL INSULATION BLANKET - FASTENER CHANGE . . . 20
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Commercial        
Airplane
Group 
 777
Service Bulletin
ALERT
SummaryNumber: 777-78A0070Date: November 20, 2008
ATA System: 7831
SUBJECT: EXHAUST (GE90) - Thrust Reverser System - GE Scavenge Tube Interference with
Thrust Reverser Insulation Blanket Bolt - Replacement
THIS BULLETIN IS SENT TO THE OPERATORS OF RECORD OF THE AIRPLANES SHOWN IN PARAGRAPH
1.A., EFFECTIVITY . IF AN AIRPLANE HAS BEEN LEASED OR SOLD, SEND THIS SERVICE BULLETIN TO
THE NEW OPERATOR. IF APPLICABLE SPARES HAVE BEEN SOLD, SEND THIS SERVICE BULLETIN TO
THE NEW OWNER.
CONCURRENT REQUIREMENTS
Refer to Paragraph 1.B., Concurrent Requirements.
BACKGROUND
Accomplishment of this service bulletin will prevent interference between an oil scavenge tube on the Turbine
Rear Frame (TRF) of the General Electric (GE) engine and an aft cowl insulation blanket bolt. This interference
can cause damage to the oil scavenge tube. This damage could result in a puncture in the oil scavenge tube.
A punctured oil scavenge tube would cause oil loss and could cause an in-flight shutdown of the engine.
Boeing determined that there was insufficient clearance between an oil scavenge tube on the GE engine and
an aft cowl insulation blanket bolt. This location could experience interference under flight loads. Damage to the
oil scavenge tube was confirmed at Boeing on non-delivered airplanes after flight. Several in-service airplanes
were also inspected. Many of the airplanes showed damage because of the interference condition.The damage
was limited to dents, gouges, or chafing. However, some of the damage that was found was outside of serviceable
limits. No oil tube punctures were found or reported.
This service bulletin provides instructions to replace the aft cowl insulation blanket fasteners at one location to
gain additional clearance from the oil scavenge tube and remove the possible interference condition.
There are two related vendor service bulletins. GE Service Bulletin 79-0017 provides instructions to inspect the
oil scavenge tube for damage and should be done concurrently with this service bulletin. GE Service Bulletin
79-0019 provides instructions to replace the oil scavenge tube with a new tube that will increase clearance with
the insulation blanket bolt.
Boeing Service Related Problem (SRP) 777-SRP-72-0032 is related to this service bulletin.
ACTION
Open the left thrust reverser. Remove the lower aft cowl insulation blanket. Change the fasteners at one location.
Install the removed insulation blanket. Close the thrust reverser.
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EFFECTIVITY
777-200LR and -300ER Airplanes with GE90-100 engines. 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.
Boeing recommends that the change given in this service bulletin be done within 180 days or 300 flight cycles
after the date on this service bulletin, whichever occurs later.
INDUSTRY SUPPORT INFORMATION
Boeing warranty remedies are not available for the changes given in this service bulletin.
MANPOWER
Elapsed HoursTotal Task HoursEngines
2.502.50Each Engine
MATERIAL INFORMATION
Boeing Supplied Kits/Parts.
Refer to Paragraph 2.A., Material - Price and Availability.
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BOEING SERVICE BULLETIN 777-78A0070
ALERT  ALERT
OPEN THE
LEFT THRUST
REVERSER
CLOSE THE
LEFT THRUST
REVERSER
REMOVE THE
LOWER AFT
COWL
INSULATION
BLANKET
CHANGE THE
FASTENERS
AT ONE
LOCATION
INSTALL THE
REMOVED
INSULATION
BLANKET
FWD
1556029
November 20, 2008
777-78A0070
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### Page 9

Commercial        
Airplane
Group 
 777
Service Bulletin
ALERT
Number: 777-78A0070
Date: November 20, 2008
ATA System: 7831
SUBJECT: EXHAUST (GE90) - Thrust Reverser System - GE Scavenge Tube Interference with
Thrust Reverser Insulation Blanket Bolt - Replacement
THIS BULLETIN IS SENT TO THE OPERATORS OF RECORD OF THE AIRPLANES SHOWN IN PARAGRAPH
1.A., EFFECTIVITY . IF AN AIRPLANE HAS BEEN LEASED OR SOLD, SEND THIS SERVICE BULLETIN TO
THE NEW OPERATOR. IF APPLICABLE SPARES HAVE BEEN SOLD, SEND THIS SERVICE BULLETIN TO
THE NEW OWNER.
1.    PLANNING INFORMATION
A. Effectivity
1. Airplanes
This service bulletin is for the airplanes shown below.
Refer to Service Bulletin Index Document D624W001 Part 3 for Airplane Variable Number, Line
Number, and Serial Number data.
DESCRIPTIONCONFIGURATIONGROUP
777-200LR and -300ER Airplanes with GE90-100 Engines-1
Airplane Models:
777-200LR, 777-300ER
GroupVariable Number
1WD001 - WD002
1WD011 - WD014
1WD031 - WD033
1WD046 - WD048
1WD501 - WD507
1WD521 - WD537
1WD546 - WD552
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GroupVariable Number
1WD561 - WD571
1WD581 - WD594
1WD606 - WD609
1WD621 - WD632
1WD651 - WD657
1WD671 - WD675
1WD691 - WD701
1WD741 - WD745
1WD761 - WD768
1WD786 - WD787
1WD796 - WD799
1WD826 - WD828
1WD846
1WD871
2. Spares Affected
None.
B. Concurrent Requirements
The service bulletin listed below must be done before or at the same time as this service bulletin:
DescriptionService BulletinCompany
Inspection of GE Engine Oil Scavenge Tube79-0017General Electric
(GE)
C. Reason
Accomplishment of this service bulletin will prevent interference between an oil scavenge tube on the
Turbine Rear Frame (TRF) of the General Electric (GE) engine and an aft cowl insulation blanket bolt.
This interference can cause damage to the oil scavenge tube. This damage could result in a puncture
in the oil scavenge tube. A punctured oil scavenge tube would cause oil loss and could cause an in-flight
shutdown of the engine.
Boeing determined that there was insufficient clearance between an oil scavenge tube on the GE
engine and an aft cowl insulation blanket bolt. This location could experience interference under flight
loads. Damage to the oil scavenge tube was confirmed at Boeing on non-delivered airplanes after
flight. Several in-service airplanes were also inspected. Many of the airplanes showed damage because
of the interference condition. The damage was limited to dents, gouges, or chafing. However, some of
the damage that was found was outside of serviceable limits. No oil tube punctures were found or
reported.
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This service bulletin provides instructions to replace the aft cowl insulation blanket fasteners at one
location to gain additional clearance from the oil scavenge tube and remove the possible interference
condition.
There are two related vendor service bulletins. GE Service Bulletin 79-0017 provides instructions to
inspect the oil scavenge tube for damage and should be done concurrently with this service bulletin.
GE Service Bulletin 79-0019 provides instructions to replace the oil scavenge tube with a new tube
that will increase clearance with the insulation blanket bolt.
Boeing Service Related Problem (SRP) 777-SRP-72-0032 is related to this service bulletin.
D. Description
Open the left thrust reverser. Remove the lower aft cowl insulation blanket. Change the fasteners at
one location. Install the removed insulation blanket. Close the thrust reverser.
The work in this service bulletin is done in the maintenance zone(s) given below.
Affected Maintenance Zones
ZoneModel
417777-200LR, 777-300ER
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.
Boeing recommends that the change given in this service bulletin be done within 180 days or 300 flight
cycles after the date on this service bulletin, whichever occurs later.
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 change for each engine.
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:
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 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.
Elapsed HoursTask HoursNumber of
Persons
Task
0.500.501Open Access
1.501.501Figure 1
0.500.501Close Access
2.502.50TOTAL FOR EACH ENGINE
H. Weight and Balance Changes
None.
I. Electrical Load Data
Not changed.
J. References
1. Existing Data
a. Service Related Problem (SRP) 777-SRP-72-0032
b. Boeing Service Letter (SL) 777-SL-78-021
c. Boeing Fleet Team Digest (FTD) Article 777-FTD-79-08001
d. 777 Aircraft Maintenance Manual (AMM) 78-31-00, 78-31-06
e. General Electric (GE) Service Bulletin 79-0017, 79-0019
NOTE: The supplier was told to send copies of the service bulletin to each operator.
2. Data supplied with this Service Bulletin
None.
3. Installation Drawings Used in the Preparation of this Service Bulletin
TitleDrawing Number
Insulation Blanket Instl. - T/R Fan Duct Inner Wall315W1810
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These drawings were used to prepare this service bulletin. These drawings are not necessary to
make the specified changes, and are not supplied with this service bulletin. These drawings may
not be applicable to all airplane configurations or operators.
K. Publications Affected
Chapter-SectionPublication
78-31777 Illustrated Parts Catalog
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
Boeing can supply the kits shown in Paragraph 2.C., Parts Necessary for Each Airplane , and Paragraph
2.D., Parts Necessary to Change Spares, as shown below. If there is a limit to the quantity (QTY) of
available kits, a supply sequence is given by Spares. More kits become available as shown in the
Reorder Lead Time (ROLT). ROLT is calculated from the date Boeing gets the purchase order.
Unit Price thru
December 31,
2008
ROLT
(Weeks)
QTYDateNameKit Number
$46.603520Jul. 14,
2008
Top Kit - GE Thrust
Reverser Blanket Bolt
Replacement
005W3383-1
20Jul. 28,
2008
24Aug. 11,
2008
20Sep. 11,
2008
20Oct. 9,
2008
20Nov. 6,
2008
20Dec. 8,
2008
20Jan. 14,
2009
20Feb. 11,
2009
20Mar. 11,
2009
20Apr. 8,
2009
20May 6,
2009
18Jun. 4,
2009
The kits are subject to the terms and conditions of the Boeing standard purchase order acknowledgment.
After the Unit Price date, new price and ROLT data is applicable. Prices are in United States dollars.
Terms: Net 30 days.
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Reference this service bulletin and submit your purchase order by one of the methods that
follow:
1. Order on-line via ATA Spec 2000 or Boeing Part Page
2. Fax to (206) 662-7145
3. Spares Customer Support - MC 36-65
Boeing Spares Department
P .O. Box 3707
Seattle, Washington 98124-2207 USA
B. Industry Support Information
Boeing warranty remedies are not available for the configuration changes given in this service bulletin.
C. Parts Necessary For Each Airplane
1. Kits/Parts
To get the kits/parts shown below, refer to Paragraph 2.A., Material - Price and Availability.
NOTE: One top kit and the items shown in Paragraph 2.C.2., Parts and Materials Supplied by
the Operator, are necessary for each engine.
Kit 005W3383
NotesExisting Part
Number
NameQTYNew Part Number
-1
Top Kit - GE Thrust
Reverser Blanket
Bolt Replacement
-005W3383-1
315W1819-2 or
315W1819-6
BOLT1315W1819-7
NUT1BACN10YR3C
WASHER, PLAIN1BACW10P392CC
(BACW10P458CD
optional)
WASHER1MS15795-857
NUT1RH30C3NL
2. Parts and Materials Supplied by the Operator
None.
3. Parts Modified and Reidentified
None.
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4. Parts Removed and Not Replaced
None.
D. Parts Necessary to Change Spares
To get the kits shown below, refer to Paragraph 2.A., Material - Price and Availability.
QTYNameKit Number
1Top Kit - GE Thrust
Reverser Blanket Bolt
Replacement
005W3383-1
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. 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 "as
given in" are included in the instruction, the procedure in the Boeing document must
be used.
B. WORK INSTRUCTIONS
1. Open the left Thrust Reverser. Refer to 777 AMM 78-31-00 as an accepted procedure.
2. Replace the insulation blanket fasteners on the aft cowl as given in Figure 1.
3. Close the left Thrust Reverser. Refer to 777 AMM 78-31-00 as an accepted procedure.
4. Put the airplane back to a serviceable condition.
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BOEING SERVICE BULLETIN 777-78A0070
ALERT  ALERT
1555958
FIGURE 1: THRUST REVERSER - AFT COWL INSULATION BLANKET - FASTENER CHANGE
(SHEET 1 OF 3)
November 20, 2008
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### Page 21 (OCR)

BOEING SERVICE BULLETIN 777-78A0070
ALERT  ALERT
14
TEWD  NUT
WASHER
INSULATION 1) 4
BLANKET
NUT
WASHER
AFT COWL
2 3 BOLT
C  1555929
FIGURE 1: THRUST REVERSER - AFT COWL INSULATION BLANKET - FASTENER CHANGE
(SHEET 2 OF 3)
November 20, 2008
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### Page 22

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 engine.
MORE DATAQTYIDENTIFICATIONNAMETASKSTEP
Refer to 777 AMM
78-31-06 as an
accepted procedure.
1315W1768-1Blanket Assembly - Aft
Cowl
Remove / Keep1
1315W1819-2 0R
315W1819-6
BoltRemove2
--WasherRemove
--NutRemove
1315W1819-7BoltInstall (New)3
1MS15795-857WasherInstall (New)
Torque to 25-35
inch-pounds.
1RH30C3NLNutInstall (New)
Refer to 777 AMM
78-31-06 as an
accepted procedure.
1315W1768-1Blanket Assembly - Aft
Cowl
Install (Kept)4
BACW10P458CD
washer is optional to
the
BACW10P392CC
washer.
1BACW10P392CCWasherInstall (New)5
Torque to 20-25
inch-pounds.
1BACN10YR3CNUTInstall (New)
(OPTIONAL) (a)1315W1819-7BoltGrind6
(a) This step is optional. If damage to the GE oil scavenge tube is found during inspection as given in GE
service bulletin 79-0017, operators can grind the 315W1819-7 bolt to provide additional clearance. Grind
the bolt until there is a minimum 1.5 threads protruding.
FIGURE 1: THRUST REVERSER - AFT COWL INSULATION BLANKET - FASTENER CHANGE
(SHEET 3 OF 3)
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