April 4, 2002 777-24-0070 BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. 1 of 22 

### Commercial Airplane Group 

# 777 Service Bulletin

Number: 777-24-0070 Date: April 4, 2002 ATA System: 2409 WJB SUBJECT: ELECTRICAL POWER - Electrical Load Management System (ELMS) - Software Change 

## BOEING PROPRIETARY, CONFIDENTIAL, AND/OR TRADE SECRET Copyright © 2002 The Boeing Company Unpublished Work - All Rights Reserved Boeing claims copyright in each page of this document only to the extent that the page contains copyrightable subject matter.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, BBJ, DC-8, DC-9, DC-10, MD-10, MD-11, MD-80, MD-88, MD-90, and the red-white-and-blue 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document unless provided in writing by Boeing.BLANK PAGE April 4, 2002 777-24-0070 BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. 2 of 22 

### BOEING SERVICE BULLETIN 777-24-0070

BLANK PAGEApril 4, 2002 777-24-0070 BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. 3 of 22 

### Commercial Airplane Group 

# 777 Service Bulletin

Number: 777-24-0070 

### Summary Date: April 4, 2002 ATA System: 2409 WJB SUBJECT: ELECTRICAL POWER - Electrical Load Management System (ELMS) - Software Change

CONCURRENT REQUIREMENTS For airplanes WB031-WB036, this change assumes service bulletin 777-26-0030 has been done. For airplane WB106, this change assumes service bulletin 777-27-0046 has been done. For airplanes WB311-WB318, this change assumes that service bulletins 777-21-0033 and 777-25-0186 have been done. For airplanes WB319- WB321this change assumes service bulletin 777-25-0186 has been done. For airplanes WB416-WB421, this change assumes service bulletin 777-25-0123 has been done. For airplanes WA101-WA104, this change assumes service bulletin 777-25-0179 has been done.

BACKGROUND This change will prevent an uncommanded deployment of the passenger oxygen masks. One operator has reported that the oxygen masks dropped while the airplane was in initial climb. The oxygen masks were not dropped by the flight crew and no fault data was found on EICAS or CMCS. It is possible, that an out of tolerance weight on wheels sensor can cause this to happen during a power interrupt. The installed electrical load management system (ELMS) software uses a fail-to-air default for the oxygen mask drop inhibit logic if a weight-on-wheels sensor is not operational. New ELMS software is available which changes the oxygen mask inhibit to a fail-to-ground logic. A weight on wheels sensor fault will not cause an uncommanded oxygen mask drop. This software change also includes the necessary changes to support future service bulletins that providefor retrofit of the passenger compartment electrical power isolation switches. For airplanes WC101-WC103 only, this software corrects the maximum landing weight for the fuel jettison calculations. The software change in this service bulletin includes the changes described in Boeing Service Bulletins 777-24- 0010, 777-24-0025 and 777-24-0039.

ACTION (PRR 61887) Change the ELMS operational software (OPS) and configuration database software (OPC) at the data loader. Do a test of the ELMS.April 4, 2002 777-24-0070 BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. 4 of 22 

### BOEING SERVICE BULLETIN 777-24-0070

EFFECTIVITY All 777 airplanes variable numbers WA001, WA101-WA104, WA210-WA212, WA221-WA223, WA231-WA232, WA241-WA250, WB016-WB021, WB031-WB044, WB105-WB106, WB133-WB135, WB151-WB153, WB161- WB173, WB271-WB272, WB276-WB286, WB291-WB301, WB306-WB307, WB311-WB327, WB336-WB337, WB366-WB367, WB371-WB386, WB406, WB411-WB413, WB416-WB433, WB446-WB452, WB476, WB481- WB484, WB501-WB507, WB531-WB535, WB551-WB554, WB591-WB595, WB601-WB606, WB631-WB632, WB636-WB637, WC051-WC067, WC101-WC103, WC111.

COMPLIANCE No compliance time is given.

INDUSTRY SUPPORT INFORMATION Boeing warranty remedies are not available for the configuration changes given in this service bulletin.

MANPOWER

MATERIAL INFORMATION Operator Supplied Parts/Materials. Refer to Paragraph 2.A., Material - Price and Availability. Airplanes TotalTask Hours Elapsed Hours All 2.0 2.0April 4, 2002 777-24-0070 BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. 5 of 22 

### Commercial Airplane Group 

# 777 Service Bulletin

Number: 777-24-0070 Date: April 4, 2002 ATA System: 2409 WJB SUBJECT: ELECTRICAL POWER - Electrical Load Management System (ELMS) - Software Change

1. PLANNING INFORMATION A. Effectivity 1. Airplanes Refer to Service Bulletin Index Document D6-24W001 Part 3 for Airplane Variable Number, Line Number, and Serial Number data. This service bulletin is for the airplanes shown below. An equivalent change is on subsequent production airplanes. Refer to PRR 61887 for data about this change. Airplane models:

777-200 777-300 IDENTIFICATION BY CUSTOMER, CUSTOMER CODE, GROUP AND VARIABLE NUMBER AEROFLOT (ARO) 1 WB336–WB337 AIR CHINA (BEJ) 1 WA241–WA250 AIR EUROPE ITALY (EIY) 1 WB366–WB367 AIR FRANCE (AFA) 1 WB311–WB327 ALL NIPPON AIRWAYS (ANA) 1 WA221–WA223 WA231–WA232 WB481–WB484 WB531–WB535 AMERICAN AIRLINES (AAL) 1 WB416–WB433 WC051–WC067April 4, 2002 777-24-0070 BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. 6 of 22 

### BOEING SERVICE BULLETIN 777-24-0070

ASIANA AIRLINES (AAR) 1 WC111 BRITISH AIRWAYS (BAB) 1 WB016–WB021 WB031–WB044 WB411–WB413 C.I.T. LEASING CORPORATION (TCI) 1 WB163 CATHAY PACIFIC AIRWAYS (CAT) 1 WA001 WA101–WA104 WB501–WB507 CONTINENTAL AIRLINES (CAL) 1 WB371–WB386 DELTA AIR LINES (DAL) 1 WB446–WB452 EGYPTAIR (EGP) 1 WB151–WB153 EL AL ISRAEL AIRLINES (ELA) 1 WC101–WC103 EMIRATES (EAD) 1 WB105–WB106 WB631–WB632 WB636–WB637 JAPAN AIR SYSTEM (JAS) 1 WA210–WA212 JAPAN AIRLINES (JAL) 1 WB591–WB595 KOREAN AIR (KAL) 1 WB133–WB135 WB551–WB554 KUWAIT AIRWAYS (KUW) 1 WB306–WB307 LAUDA AIR (LAL) 1 WB271–WB272 MALAYSIA AIRLINES (MAS) 1 WB161–WB162 WB164–WB173 MID EAST JET (SKL) 1 WB406 SAUDI ARABIAN AIRLINES (SVA) 1 WB276–WB286 WB291–WB301 SAUDI OGER (SAO) 1 WB476April 4, 2002 777-24-0070 BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. 7 of 22 

### BOEING SERVICE BULLETIN 777-24-0070

THAI AIRWAYS INTERNATIONAL (TII) 1 WB601–WB606

IDENTIFICATION BY VARIABLE NUMBER Variable Group WA001 1 WA101–WA104 1 WA210–WA212 1 WA221–WA223 1 WA231–WA232 1 WA241–WA250 1 WB016–WB021 1 WB031–WB044 1 WB105–WB106 1 WB133–WB135 1 WB151–WB153 1 WB161–WB173 1 WB271–WB272 1 WB276–WB286 1 WB291–WB301 1 WB306–WB307 1 WB311–WB327 1 WB336–WB337 1 WB366–WB367 1 WB371–WB386 1 WB406 1 WB411–WB413 1 WB416–WB433 1 WB446–WB452 1 WB476 1 WB481–WB484 1 WB501–WB507 1 WB531–WB535 1 WB551–WB554 1 WB591–WB595 1 WB601–WB606 1 WB631–WB632 1 WB636–WB637 1April 4, 2002 777-24-0070 BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. 8 of 22 

### BOEING SERVICE BULLETIN 777-24-0070

2. Spares Affected

None. B. Concurrent Requirements For airplanes WB031-WB036, this change assumes service bulletin 777-26-0030 has been done. For airplane WB106, this change assumes service bulletin 777-27-0046 has been done. For airplanes WB311-WB318, this change assumes that service bulletins 777-21-0033 and 777-25-0186 have been done. For airplanes WB319-WB321this change assumes service bulletin 777-25-0186 has been done. For airplanes WB416-WB421, this change assumes service bulletin 777-25-0123 has been done. For airplanes WA101-WA104, this change assumes service bulletin 777-25-0179 has been done.

C. Reason This change will prevent an uncommanded deployment of the passenger oxygen masks. One operator has reported that the oxygen masks dropped while the airplane was in initial climb. The oxygen masks were not dropped by the flight crew and no fault data was found on EICAS or CMCS. It is possible, that an out of tolerance weight on wheels sensor can cause this to happen during a power interrupt. The installed electrical load management system (ELMS) software uses a fail-to-air default for the oxygen mask drop inhibit logic if a weight-on-wheels sensor is not operational. New ELMS software is available which changes the oxygen mask inhibit to a fail-to-ground logic. A weight on wheels sensor fault will not cause an uncommanded oxygen mask drop. This software change also includes the necessary changes to support future service bulletins that providefor retrofit of the passenger compartment electrical power isolation switches. For airplanes WC101-WC103 only, this software corrects the maximum landing weight for the fuel jettison calculations. The software change in this service bulletin includes the changes described in Boeing Service Bulletins 777-24-0010, 777-24-0025 and 777-24-0039. D. Description The ELMS operational software (OPS) and configuration database software (OPC) are changed at the data loader. A test of the ELMS and the oxygen mask deployment system is done. E. Compliance No compliance time is given. WC051–WC067 1 WC101–WC103 1 WC111 1 Variable GroupApril 4, 2002 777-24-0070 BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. 9 of 22 

### BOEING SERVICE BULLETIN 777-24-0070

F. Approval This service bulletin was examined by the Federal Aviation Administration (FAA). The changes specified in this service bulletin comply with the applicable Federal Aviation Regulations (FAR) and are FAA approved. This service bulletin and the FAA approval were based on the airplane in its original Boeing delivery configuration or as modified by other FAA 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.

Note: Joint Airworthiness Requirements (JAR) compliance status may be found in the Service Bulletin Index, Part 1. G. Manpower

H. Weight and Balance Changes

None.

I. Electrical Load Data Not changed.

J. References 1. Existing Data: a. Engineering Change Memo PRR 61887 b. 777 Maintenance Manual (AMM) Subject 24-09-00 c. Boeing Service Bulletins 777-21-0033, 777-24-0010, 777-24-0025, 777-24-0039, 777-25- 0123, 777-25-0179, 777-25-0186, 777-26-0030 and 777-27-0046 2. Data supplied with this Service Bulletin:

None. 3. Installation Drawings Used in the Preparation of this Service Bulletin:

None.

Task Number of Persons Task-Hours Elapsed Hours Load new Software 1 2.0 2.0 TOTAL FOR EACH AIRPLANE 2.0 2.0April 4, 2002 777-24-0070 BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. 10 of 22 

### BOEING SERVICE BULLETIN 777-24-0070

K. Publications Affected

L. Interchangeability and Intermixability of Parts Accomplishment of this service bulletin does not affect interchangeability or intermixability of parts. Publication Chapter-Section 777 Illustrated Parts Catalog 24-09April 4, 2002 777-24-0070 BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. 11 of 22 

### BOEING SERVICE BULLETIN 777-24-0070

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. 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:

None.April 4, 2002 777-24-0070 BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. 12 of 22 

### BOEING SERVICE BULLETIN 777-24-0070

2. Parts and Materials Supplied by the Operator:

Part Number / Specification QTY Name Notes S281W601-229 1 Disc Set (a) (b) S281W601-240 1 Disc Set (a) (c) S281W601-241 1 Disc Set (a) (d) S281W601-242 1 Disc Set (a) (e) S281W601-245 1 Disc Set (a) (f) S281W601-246 1 Disc Set (a) (g) S281W601-251 1 Disc Set (a) (h) S281W601-252 1 Disc Set (a) (i) S281W601-256 1 Disc Set (a) (j) S281W601-257 1 Disc Set (a) (k) S281W601-258 1 Disc Set (a) (l) S281W601-261 1 Disc Set (a) (m) S281W601-263 1 Disc Set (a) (n) S281W601-266 1 Disc Set (a) (o) S281W601-267 1 Disc Set (a) (p) S281W601-268 1 Disc Set (a) (q) S281W601-269 1 Disc Set (a) (r) S281W601-270 1 Disc Set (a) (s) S281W601-271 1 Disc Set (a) (t) S281W601-273 1 Disc Set (a) (u) S281W601-274 1 Disc Set (a) (v) S281W601-275 1 Disc Set (a) (w) S281W601-276 1 Disc Set (a) (x) S281W601-277 1 Disc Set (a) (y) S281W601-278 1 Disc Set (a) (z) S281W601-279 1 Disc Set (a) (aa) S281W601-281 1 Disc Set (a) (ab) S281W601-282 1 Disc Set (a) (ac) S281W601-283 1 Disc Set (a) (ad) S281W601-286 1 Disc Set (a) (ae) S281W601-290 1 Disc Set (a) (af) S281W601-291 1 Disc Set (a) (ag) S281W601-292 1 Disc Set (a) (ah) S281W601-294 1 Disc Set (a) (ai) S281W601-295 1 Disc Set (a) (aj) (a) Smiths Industries Aerospace and Defense Systems (VK5294), Evesham Road Bishops Cleeve, Cheltenham, Gloucestershire GL52 4SF EnglandApril 4, 2002 777-24-0070 BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. 13 of 22 

### BOEING SERVICE BULLETIN 777-24-0070

(b) OPS software part number 2466-SMI-000-70 and OPC software part number 241F-SMIA01-97 for airplane WA001.(c) OPS software part number 2466-SMI-000-70 and OPC software part number 2410-SMIA01-98 for airplane WA210-WA212.(d) OPS software part number 2466-SMI-000-70 and OPC software part number 241C-SMIA01-85 for airplane WA221-WA223, WA231-WA232.(e) OPS software part number 2466-SMI-000-70 and OPC software part number 241F-SMIA01-86 for airplane WA241-WA250.(f) OPS software part number 2466-SMI-000-70 and OPC software part number 241E-SMIA01-87 for airplane WB016-WB021, WB411-WB413.(g) OPS software part number 2466-SMI-000-70 and OPC software part number 2414-SMIA01-63 for airplane WB031-WB044.(h) OPS software part number 2466-SMI-000-70 and OPC software part number 2411-SMIA01-99 for airplane WB105.(i) OPS software part number 2466-SMI-000-70 and OPC software part number 2412-SMIA02-00 for airplane WB106.(j) OPS software part number 2466-SMI-000-70 and OPC software part number 2413-SMIA01-64 for airplane WB151-WB153.(k) OPS software part number 2466-SMI-000-70 and OPC software part number 2411-SMIA01-88 for airplane WB161-WB169.(l) OPS software part number 2466-SMI-000-70 and OPC software part number 241B-SMIA01-82 for airplane WB170-WB173.(m) OPS software part number 2466-SMI-000-70 and OPC software part number 241FSMI-A01-79 for airplane WB271-WB272.(n) OPS software part number 2466-SMI-000-70 and OPC software part number 2410-SMIA01-89 for airplane WB306-WB307.(o) OPS software part number 2466-SMI-000-70 and OPC software part number 2412-SMIA01-65 for airplane WB311-WB327.(p) OPS software part number 2466-SMI-000-70 and OPC software part number 2418-SMIA01-90 for airplane WBWB336-WB337, WB481.(q) OPS software part number 2466-SMI-000-70 and OPC software part number 2419-SMIA01-91 for airplane WB366-WB367.(r) OPS software part number 2466-SMI-000-70 and OPC software part number 2419-SMIA01-80 for airplane WB371-WB386.(s) OPS software part number 2466-SMI-000-70 and OPC software part number 2413-SMIA02-01 for airplane WB406.(t) OPS software part number 2466-SMI-000-70 and OPC software part number 2418-SMIA01-81 for airplane WB416-WB433.(u) OPS software part number 2466-SMI-000-70 and OPC software part number 241E-SMIA01-78 for airplane WB446-WB452 (without the crew rest installed).(v) OPS software part number 2466-SMI-000-70 and OPC software part number 2410-SMIA02-02 for airplane WB476. Part Number / Specification QTY Name NotesApril 4, 2002 777-24-0070 BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. 14 of 22 

### BOEING SERVICE BULLETIN 777-24-0070

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.(w) OPS software part number 2466-SMI-000-70 and OPC software part number 2411-SMIA02-03 for airplane WB501-WB507.(x) OPS software part number 2466-SMI-000-70 and OPC software part number 241A-SMIA01-92 for airplane WB531-WB535.(y) OPS software part number 2466-SMI-000-70 and OPC software part number 241B-SMIA01-93 for airplane WB551-WB554.(z) OPS software part number 2466-SMI-000-70 and OPC software part number 241C-SMIA01-94 for airplane WB591-WB595.(aa) OPS software part number 2466-SMI-000-70 and OPC software part number 241DSMI-A01-95 for airplane WB601-WB606.(ab) OPS software part number 2466-SMI-000-70 and OPC software part number 241ASMI-A01-83 for airplane WB631-WB632, WB636-WB637. (ac) OPS software part number 2466-SMI-000-70 and OPC software part number 2417- SMI-A02-05 for airplane WC101-WC103. (ad) OPS software part number 2466-SMI-000-70 and OPC software part number 2416- SMI-A01-61 for airplane WC111. (ae) OPS software part number 2466-SMI-000-70 and OPC software part number 2417- SMI-A01-71 for airplane WB446-WB452 (with the crew rest installed). (af) OPS software part number 2466-SMI-000-70 and OPC software part number 2413- SMI-A01-75 for airplane WC051-WC067. (ag) OPS software part number 2466-SMI-000-70 and OPC software part number 2410- SMI-A01-76 for airplane WB133-WB135. (ah) OPS software part number 2466-SMI-000-70 and OPC software part number 2412- SMI-A01-74 for airplane WB276-WB286, WB291-WB301.(ai) OPS software part number 2466-SMI-000-70 and OPC software part number 2416-SMIA02-04 for airplane WA101-WA104.(aj) OPS software part number 2466-SMI-000-70 and OPC software part number 241ESMI-A01-96 for airplane WB482-WB484. Part Number / Specification QTY Name NotesApril 4, 2002 777-24-0070 BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. 15 of 22 

### BOEING SERVICE BULLETIN 777-24-0070

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.April 4, 2002 777-24-0070 BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. 16 of 22 

### BOEING SERVICE BULLETIN 777-24-0070

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### BOEING SERVICE BULLETIN 777-24-0070

3. ACCOMPLISHMENT INSTRUCTIONS

A. GENERAL INFORMATION

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.

B. WORK INSTRUCTIONS 1. Prepare the software dataloader to install new ELMS software. Refer to the 777 AMM 24-09-00, ELMS Electronic Unit - Software Installation. 2. Install the new ELMS software. Refer to the paragraph 2.C.2, Parts and Materials Supplied by the Operator, to get the part number of the software. 3. Put the airplane back to a serviceable condition.BLANK PAGE April 4, 2002 777-24-0070 BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. 18 of 22 

### BOEING SERVICE BULLETIN 777-24-0070

BLANK PAGETable of Contents April 4, 2002 777-24-0070 BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. 19 of 22 

### BOEING SERVICE BULLETIN 777-24-0070

Table of Contents Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 1. PLANNING INFORMATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 A. Effectivity . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 1. Airplanes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 2. Spares Affected . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8 B. Concurrent Requirements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8 C. Reason . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8 D. Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8 E. Compliance. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8 F. Approval . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9 G. Manpower . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9 H. Weight and Balance Changes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9 I. Electrical Load Data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9 J. References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9 1. Existing Data: . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9 2. Data supplied with this Service Bulletin: . . . . . . . . . . . . . . . . . . . . . . . . . . 9 3. Installation Drawings Used in the Preparation of this Service Bulletin: . . . . . . . . . . . 9 K. Publications Affected . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10 L. Interchangeability and Intermixability of Parts . . . . . . . . . . . . . . . . . . . . . . . . . 10 2. MATERIAL INFORMATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11 A. Material - Price and Availability. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11 B. Industry Support Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11 C. Parts Necessary For Each Airplane . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11 1. Kits: . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11 2. Parts and Materials Supplied by the Operator: . . . . . . . . . . . . . . . . . . . . . . 12 3. Parts Modified and Reidentified: . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14 4. Parts Removed and Not Replaced: . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14 D. Parts Necessary to Change Spares . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14 E. Special Tooling - Price and Availability. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14 F. Special Tooling Necessary to do this Service Bulletin . . . . . . . . . . . . . . . . . . . . . 15 3. ACCOMPLISHMENT INSTRUCTIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17 A. GENERAL INFORMATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17 B. WORK INSTRUCTIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17BLANK PAGE April 4, 2002 777-24-0070 BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. 20 of 22 

### BOEING SERVICE BULLETIN 777-24-0070

BLANK PAGEApril 4, 2002 777-24-0070 BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. 21 of 22 

### Commercial Airplane Group 

# 777 Service Bulletin

Number: 777-24-0070 

### Evaluation Form Date: April 4, 2002 ATA System: 2409 WJB SUBJECT: ELECTRICAL POWER - Electrical Load Management System (ELMS) - Software Change

Use this evaluation form to tell us what you think of the quality of this service bulletin. We will use the data that you give us to improve the quality of our service bulletins.

Note: Please do not use this evaluation form to tell us to make changes to your manuals. To make these changes, please use a Publication Change Request (PCR) form. Please give us this data: (If necessary, please use the other side. Thank you for the time you used to give us your comments.) OPERATOR: ______________________________________ TODAY’S DATE:_______________________ PREPARED BY: ___________________________________ TITLE: ______________________________ ORGANIZATION: __________________________________ TELEX CODE: ________________________ TELEPHONE NUMBER: _____________________________ BASE: ______________________________ Please rate the quality of this service bulletin: (good) 4 3 2 1 (poor) Please rate the quality of the illustrations: (good) 4 3 2 1 (poor) Will you do the change given by this service bulletin? Yes___ No___ If not, please explain: Is this service bulletin easy to understand? Yes___ No___ If not, please explain: Is this service bulletin easy to use? Yes___ No___ If not, please explain: Are the Planning Information, Material Information, and Accomplishment Instructions accurate? Yes___ No___ If not, please explain: Is the Manpower estimate accurate? Yes___ No___ If not, please explain: Give the completed evaluation form to your Boeing Field Service Representative or send the evaluation form directly to this address: Manager, Service Bulletin Engineering Boeing Commercial Airplanes Group P.O. Box 3707, Mail Code 2H-36 Seattle, WA 98124-2207April 4, 2002 777-24-0070 BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. 22 of 22 

### BOEING SERVICE BULLETIN 777-24-0070