### Commercial **Airplanes** 

# 777 Service Bulletin
**Number: 777-75A0002** Original Issue: January 12, 2011 Revision 1: October 26, 2011 ATA System: 7533 **SUBJECT:** AIR (RB211 Trent Engines) - Compressor Control - Compressor Bleed Control System - Intermediate Compressor 8th Stage (IP8) Bleed Air Change 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. 9E991 ECCN: 

## BOEING PROPRIETARY, CONFIDENTIAL, AND/OR TRADE SECRET Copyright © 2011 The Boeing Company Unpublished Work - All Rights Reserved Boeing claims copyright in each page of this document only to the extent that the page contains copyrightable subject matter. Boeing also claims copyright in this document as a compilation and/or collective work. This document includes proprietary information owned by The Boeing Company and/or one or more third parties. Treatment of the document and the information it contains is governed by contract with Boeing. For more information, contact The Boeing Company, P.O. Box 3707, Seattle, Washington 98124. Boeing, the Boeing signature, the Boeing symbol, 707, 717, 727, 737, 747, 757, 767, 777, 787, Dreamliner, BBJ, DC-8, DC-9, DC-10, KC-10, KDC-10, MD-10, MD-11, MD-80, MD-88, MD-90, P-8A, Poseidon and the Boeing livery are all trademarks owned by The Boeing Company; and no trademark license is granted in connection with this document unless provided in writing by Boeing.

BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: January 12, 2011 777-75A0002 Revision 1: October 26, 2011 1 of 20 6.0BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: January 12, 2011 777-75A0002 Revision 1: October 26, 2011 2 of 20 **BOEING SERVICE BULLETIN 777-75A0002**

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 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13 D. Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13 E. Compliance. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13 F. Approval . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14 G. Manpower . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14 H. Weight and Balance Changes. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14 I. Electrical Load Data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14 J. References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15 1. Existing Data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15 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. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19

BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: January 12, 2011 777-75A0002 Revision 1: October 26, 2011 3 of 20 **BOEING SERVICE BULLETIN 777-75A0002**BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: January 12, 2011 777-75A0002 Revision 1: October 26, 2011 4 of 20 **BOEING SERVICE BULLETIN 777-75A0002**

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### Commercial **Airplanes** 

# 777 Service Bulletin **Revision Transmittal Sheet Number: 777-75A0002**  Original Issue: January 12, 2011 Revision 1: October 26, 2011 ATA System: 7533 **SUBJECT:** AIR (RB211 Trent Engines) - Compressor Control - Compressor Bleed Control System - Intermediate Compressor 8th Stage (IP8) Bleed Air Change This revision includes all pages of the service bulletin. **COMPLIANCE INFORMATION RELATED TO THIS REVISION** No more work is necessary on the airplane(s) changed in accordance with the original issue of this service bulletin. **REASON FOR REVISION** This revision is sent to add the Revision 1 of Boeing Service Bulletin 777-31-0177 and to call out the latest Revision of Rolls-Royce Service Bulletin RB.211-75-G466 in Paragraph 1.B., Concurrent Requirements, and to change the warranty statement. These sections were changed: 1. In Paragraph 1.B., Concurrent Requirements, added the Revision 1 of Boeing Service Bulletin 777-31-0177 and called out the latest Revision of Rolls-Royce Service Bulletin RB.211-75-G466. 2. In Summary, Industry Support Information and in Paragraph 2.B., Industry Support Information, changed the warranty statement. Vertical lines are put on the left edge of each page, except in Paragraph 1.A., Effectivity, to show the location of important changes. Pages with no vertical lines have no important changes. **REVISION HISTORY** January 12, 2011 Original Issue: October 26, 2011 Revision 1:

BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: January 12, 2011 777-75A0002 Revision 1: October 26, 2011 5 of 20BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: January 12, 2011 777-75A0002 Revision 1: October 26, 2011 6 of 20 **BOEING SERVICE BULLETIN 777-75A0002**

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### Commercial **Airplanes** 

# 777 Service Bulletin **Summary Number: 777-75A0002**  Original Issue: January 12, 2011 Revision 1: October 26, 2011 ATA System: 7533 **SUBJECT:** AIR (RB211 Trent Engines) - Compressor Control - Compressor Bleed Control System - Intermediate Compressor 8th Stage (IP8) Bleed Air Change **CONCURRENT REQUIREMENTS** Refer to Paragraph 1.B., Concurrent Requirements. **BACKGROUND** This service bulletin gives instructions to change the intermediate compressor 8th stage (IP8) bleed valve outlet screen for Number 1, Number 2, and Number 4 bleed valves. Additionally, tubing is revised to reverse the Number 1 and Number 2 bleed valve schedule. This action provides revised IP8 bleed air mixing to reduce temperatures experienced by the inner wall of the thrust reverser (TR) during flight to prevent inner wall and fitting damage. If you do not do this service bulletin, the thrust reverser could be damaged by excessive heat which could result in thrust reverser separation at departure which could in turn cause a runway excursion because of thrust asymmetry from forward thrust on a Refused Take Off (RTO). Accomplishment of the service bulletin will improve the thermal protection of the thrust reverser. The existing Thermal Protection System (TPS) as modified by Boeing Service Bulletins 777-78-0071 and 777-78-0082, was developed to protect the thrust reverser inner wall from the engine side of the thrust reverser. The changes provided by this service bulletin will add thermal protection to the thrust reverser inner wall from the fan duct side of the thrust reverser. Thermal degradation has caused structural pieces of the thrust reverser inner wall to separate from the thrust reverser in flight. Poor mixing of IP8 bleed air contributes to the overheating that results in disbondments and delaminations in the inner wall and weakens the compression and drag link fittings. Thirteen 777 Rolls-Royce TR events related to thermal damage of the TR inner wall have occurred since 2003. The events have included such things as Air Turn Backs (ATB), In Flight Shut Downs (IFSD), TR inner wall panel collapse, engine fire loop messages, and TR inner wall panel sections and parts being liberated from the airplane. No hull loss or personal injury has occurred from these events. Boeing Service Related Problem (SRP) 777-SRP-78-0052 is related to this service bulletin. **ACTION** On both engines, open thrust reversers and modify all three intermediate compressor 8th stage (IP8) bleed valves. Modify tubing between right upper and lower bleed valves. Refer to Rolls-Royce SB RB.211-75-G466 for detailed instructions. **EFFECTIVITY** 777-200/-300 Airplanes with Rolls-Royce RB211 Trent 800 engines. Refer to Paragraph 1.A.1., Airplanes for the list of affected airplanes.

BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: January 12, 2011 777-75A0002 Revision 1: October 26, 2011 7 of 20**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 on each engine within three years after the original issue date of this service bulletin. **INDUSTRY SUPPORT INFORMATION** Boeing warranty remedies are not available for the configuration changes given in this service bulletin. **MANPOWER Manpower Table**  **Elapsed Hours Task Hours**  **Number of Persons Task**  1.00 2.00 2 Open Access 1.00 2.00 2 Close Access 2.0 4.0 TOTAL FOR EACH ENGINE The time to do Rolls-Royce SB RB.211-75-G466 and Boeing Service Bulletin 777-31-0177 is not included. **MATERIAL INFORMATION** Operator Supplied Parts/Materials. Refer to Rolls-Royce SB RB.211-75-G466.

BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: January 12, 2011 777-75A0002 Revision 1: October 26, 2011 8 of 20 **BOEING SERVICE BULLETIN 777-75A0002**BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: January 12, 2011 777-75A0002 Revision 1: October 26, 2011 9 of 20 **BOEING SERVICE BULLETIN 777-75A0002**BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: January 12, 2011 777-75A0002 Revision 1: October 26, 2011 10 of 20 **BOEING SERVICE BULLETIN 777-75A0002**

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### Commercial **Airplanes** 

# 777 Service Bulletin
**Number: 777-75A0002** Original Issue: January 12, 2011 Revision 1: October 26, 2011 ATA System: 7533 **SUBJECT:** AIR (RB211 Trent Engines) - Compressor Control - Compressor Bleed Control System - Intermediate Compressor 8th Stage (IP8) Bleed Air Change
**1. PLANNING INFORMATION A. Effectivity**  1. Airplanes Refer to Service Bulletin Index Document D624W001 Part 3 for Airplane Variable Number, Line Number, and Serial Number data. This service bulletin is for the airplanes shown below.
**DESCRIPTION CONFIGURATION**  **GROUP** 777-200/-300 airplanes through line number 796 with Rolls-Royce RB211 Trent 800 engines. - 1

Airplane Models: 777-200, 777-300 **Group Variable Number**  1 WA001 1 WA086 - WA093 1 WA101 - WA104 1 WA196 - WA198 1 WB031 - WB042 1 WB044 - WB046 1 WB101 - WB106 1 WB161 - WB177 1 WB181 - WB194 1 WB201 - WB215

BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: January 12, 2011 777-75A0002 Revision 1: October 26, 2011 11 of 20**Group Variable Number**  1 WB231 - WB247 1 WB416 - WB439 1 WB446 - WB453 1 WB501 - WB512 1 WB601 - WB606 1 WB611 - WB622 1 WB631 - WB638 1 WB646 - WB649 1 WC051 - WC073 1 WC101 - WC104 1 WC456 - WC459 1 WC486 - WC493 1 WC531 - WC536 1 WC566 - WC567 1 WC571 - WC574 2. Spares Affected Modify spare engines in accordance with Rolls-Royce SB RB.211-75-G466. **B. Concurrent Requirements** The service bulletins listed below must be done before or at the same time as this service bulletin: **Description Service Bulletin**  **Company** AIR - IP BLEED VALVES - INTRODUCTION OF AN IP8 BLEED VALVE FEATURING A REVISED SILENCER AND ASSOCIATED CORE ENGINE DRESSINGS CHANGES Rolls-Royce SB RB.211-75-G466 dated Jun.20/11 Rolls-Royce

INDICATING/RECORDING SYSTEMS - Airplane Information Management System - Aero Engine Data Base Software Upgrade 777-31-0177 Original Issue or Revision 1 Boeing

BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: January 12, 2011 777-75A0002 Revision 1: October 26, 2011 12 of 20 **BOEING SERVICE BULLETIN 777-75A0002 C. Reason**  This service bulletin gives instructions to change the intermediate compressor 8th stage (IP8) bleed valve outlet screen for Number 1, Number 2, and Number 4 bleed valves. Additionally, tubing is revised to reverse the Number 1 and Number 2 bleed valve schedule. This action provides revised IP8 bleed air mixing to reduce temperatures experienced by the inner wall of the thrust reverser (TR) during flight to prevent inner wall and fitting damage. If you do not do this service bulletin, the thrust reverser could be damaged by excessive heat which could result in thrust reverser separation at departure which could in turn cause a runway excursion because of thrust asymmetry from forward thrust on a Refused Take Off (RTO). Accomplishment of the service bulletin will improve the thermal protection of the thrust reverser. The existing Thermal Protection System (TPS) as modified by Boeing Service Bulletins 777-78-0071 and 777-78-0082, was developed to protect the thrust reverser inner wall from the engine side of the thrust reverser. The changes provided by this service bulletin will add thermal protection to the thrust reverser inner wall from the fan duct side of the thrust reverser. Thermal degradation has caused structural pieces of the thrust reverser inner wall to separate from the thrust reverser in flight. Poor mixing of IP8 bleed air contributes to the overheating that results in disbondments and delaminations in the inner wall and weakens the compression and drag link fittings. Thirteen 777 Rolls-Royce TR events related to thermal damage of the TR inner wall have occurred since 2003. The events have included such things as Air Turn Backs (ATB), In Flight Shut Downs (IFSD), TR inner wall panel collapse, engine fire loop messages, and TR inner wall panel sections and parts being liberated from the airplane. No hull loss or personal injury has occurred from these events. Boeing Service Related Problem (SRP) 777-SRP-78-0052 is related to this service bulletin. Revision 1 is sent to add the Revision 1 of Boeing Service Bulletin 777-31-0177 and to call out the latest Revision of Rolls-Royce Service Bulletin RB.211-75-G466 in Paragraph 1.B., Concurrent Requirements, and to change the warranty statement. **D. Description** On both engines, open thrust reversers and modify all three intermediate compressor 8th stage (IP8) bleed valves. Modify tubing between right upper and lower bleed valves. Refer to Rolls-Royce SB RB.211-75-G466 for detailed instructions. Revision 1 - No more work is necessary on the airplane(s) changed in accordance with the original issue of this service bulletin. The work in this service bulletin is done in the maintenance zone(s) given below.
**Affected Maintenance Zones Zone**  **Model** 411, 421 777-200, 777-300 **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 PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: January 12, 2011 777-75A0002 Revision 1: October 26, 2011 13 of 20 **BOEING SERVICE BULLETIN 777-75A0002**Boeing recommends that the change given in this service bulletin be done on each engine, within three years after the original issue date of this service bulletin. **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: • 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. **Manpower Table - Work Package 1 or 2 Elapsed Hours**  **Task Hours Number of Persons**  **Task** 1.00 2.00 2 Open Access 1.00 2.00 2 Close Access 2.0 4.0 TOTAL FOR EACH ENGINE The time to do Rolls-Royce SB RB.211-75-G466 and Boeing Service Bulletin 777-31-0177 is not included. **H. Weight and Balance Changes Change in Moment**  **(Pound-Inches) Change in Weight**  **(Pounds) Airplane**  + 10259 + 10.2 All
**I. Electrical Load Data** Not changed.

BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: January 12, 2011 777-75A0002 Revision 1: October 26, 2011 14 of 20 **BOEING SERVICE BULLETIN 777-75A0002 J. References**  1. Existing Data a. Boeing Service Bulletin 777-31-0177, 777-78-0071, 777-78-0082 b. Boeing Service Related Problem (SRP) 777-SRP-78-0052 c. 777 Aircraft Maintenance Manual (AMM) 75-33-16 d. Rolls-Royce Service Bulletin RB.211-75-G466 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: **Chapter-Section**

**Publication** AFM-DPI 777 FAA Approved Airplane Flight Manual 75-33 777 Aircraft Maintenance Manual 75-33 777 System Schematic Manual 75-34 777 Fault Isolation Manual 2. Damage Tolerance Based Structural Inspections: Boeing has evaluated the repairs and/or changes in this service bulletin for effects on Fatigue Critical Structure (FCS) and for changes to Damage Tolerance Inspections (DTI) required in the Maintenance Program. This service bulletin does not affect FCS, therefore DTIs are not necessary. **L. Interchangeability and Intermixability of Parts** Accomplishment of this service bulletin does not affect interchangeability or intermixability of engines on an airplane providing Boeing Service Bulletin 777-31-0177 is accomplished previously or concurrently. Intermixability of modified and unmodified parts installed in accordance with Rolls-Royce SB RB.211-75-G466 on one engine is not permitted.

BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: January 12, 2011 777-75A0002 Revision 1: October 26, 2011 15 of 20 **BOEING SERVICE BULLETIN 777-75A0002**BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: January 12, 2011 777-75A0002 Revision 1: October 26, 2011 16 of 20 **BOEING SERVICE BULLETIN 777-75A0002**

BLANK PAGE**2. MATERIAL INFORMATION A. Material - Price and Availability**  Refer to Rolls-Royce SB RB.211-75-G466. **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 Refer to Rolls-Royce SB RB.211-75-G466. 2. Parts and Materials Supplied by the Operator Refer to Rolls-Royce SB RB.211-75-G466. 3. Parts Modified and Reidentified Refer to Rolls-Royce SB RB.211-75-G466. 4. Parts Removed and Not Replaced Refer to Rolls-Royce SB RB.211-75-G466. **D. Parts Necessary to Change Spares** Refer to Rolls-Royce SB RB.211-75-G466. **E. Special Tooling - Price and Availability** Refer to Rolls-Royce SB RB.211-75-G466. **F. Special Tooling Necessary to do this Service Bulletin** Refer to Rolls-Royce SB RB.211-75-G466.

BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: January 12, 2011 777-75A0002 Revision 1: October 26, 2011 17 of 20 **BOEING SERVICE BULLETIN 777-75A0002**BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: January 12, 2011 777-75A0002 Revision 1: October 26, 2011 18 of 20 **BOEING SERVICE BULLETIN 777-75A0002**

BLANK PAGE**3. ACCOMPLISHMENT INSTRUCTIONS A. GENERAL INFORMATION**  **WARNING:** IN ORDER TO REDUCE THE POTENTIAL FOR MULTIPLE-ENGINE IN-FLIGHT SHUTDOWN, POWER LOSS, OR OTHER ANOMALY DUE TO MAINTENANCE ERROR, BOEING RECOMMENDS THAT OPERATORS AVOID PERFORMING MAINTENANCE ON MULTIPLE ENGINES INSTALLED ON THE SAME AIRCRAFT AT THE SAME TIME. IF IT IS NOT POSSIBLE TO AVOID MAINTENANCE ON MORE THAN ONE ENGINE AT THE SAME TIME, BOEING RECOMMENDS THAT ADDITIONAL CONTROLS ARE APPLIED IN ORDER TO MAKE SURE THAT MAINTENANCE TASKS HAVE BEEN COMPLETED AS DEFINED. MAINTENANCE GUIDELINES SHOULD BE REVISED, WHERE POSSIBLE, TO PROMOTE THIS RECOMMENDATION. **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. The work instructions are divided into work packages. Task Hours and Elapsed Hours for each package are given in Paragraph 1.G., Manpower. You can do each work package independently. 4. These work instructions refer to procedures included in other Boeing and supplier 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 or supplier document must be used. **B. WORK INSTRUCTIONS** 1. Work Package 1 - Left Engine a. Gain access for removal of bleed valves. Refer to 777 AMM 75-33-16 as an accepted procedure. **NOTE:** Thrust reversers may be either opened or removed. b. Replace bleed valve parts and tubing in accordance with Rolls-Royce SB RB.211-75-G466 dated June 20, 2011. c. Put the airplane back to a serviceable condition. 2. Work Package 2 - Right Engine a. Gain access for removal of bleed valves. Refer to 777 AMM 75-33-16 as an accepted procedure.

BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: January 12, 2011 777-75A0002 Revision 1: October 26, 2011 19 of 20 **BOEING SERVICE BULLETIN 777-75A0002 NOTE:**  Thrust reversers may be either opened or removed. b. Replace bleed valve parts and tubing in accordance with Rolls-Royce SB RB.211-75-G466 dated June 20, 2011. c. Put the airplane back to a serviceable condition.

BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: January 12, 2011 777-75A0002 Revision 1: October 26, 2011 20 of 20 **BOEING SERVICE BULLETIN 777-75A0002**