P.O. Box 31, DERBY DE24 8BJ, UK Telephone: 44 (0) 1332 242424 Fax: 44 (0) 1332 249936 

# Rol Is-Royce
m 

# TRANSMITTA The technical informationcontained in this document has been approved under the authority of - See Planning Information, Approval.
Signed Date Jun. 29/11 N. J. Wright

RB211-524G/H-T SERIES PROPULSION SYSTEMS SERVICE BULLETIN 

# ALERT

This document transmits Revision 2 to Service Bulletin RB211-73-AGO54 Document History Service Bulletin Revision Status Initial Issue Mar.l8/10 Revision 1 Jun.27/11 Bulletin Revision 2 Remove All pages of the Service Bulletin Supplement Revision Status

Incorporate Pages 1 to 9 of the Service Bulletin



# ALERT Reason for change To correct revision number of AEC Service Bulletin referenced in this Ro 11 s-Royce Se rvi ce Bulletin (RR RMR SB0161)

Transmittal 

### - Page 1 of 2

CHECK THAT ALL PREVIOUS TRANSMllTALS HAVE BEEN INCORPORATED If any have not been received please advise Customer Data Services, Rolls-Royce plc, Derby, England O Rolls-Royce plc (date as above) Printed in Great BritainLIST OF EFFECTIVE PAGES The effective pages to this Service Bulletin following incorporation of Revision 2 are as follows: Page Revision Number Revision Date

Bulletin R 1 2 Jun.29/11 R 2 2 Jun.29/11 R 3 2 Jun.29/11 R 4 2 Jun.29/11 R 5 2 Jun.29/11 R 6 2 Jun.29/11 R 7 2 Jun.29/11 R 8 2 Jun.29/11 R 9 2 Jun.29/11Printed in Great Britain



# RB.211−73−AG054 Transmittal - Page 21. Planning Information A. Effectivity (1) Boeing 747 RB211-524G2-19, 524G2-19/11, 524G2-19/15,524G2-T-19, 524G2-T-19/11, 524G2-T-19/15,524G3-19, 524G3-19/15,524G3-T-19, 524G3-T-19/15,524H2-19, 524H2-19/11, 524H2-19/15,524H2-T-19, 524H2-T-19/11, 524H2-T-19/15 Engines prior to Serial No.13820. (2) Boeing 767 RB211-524H-36, 524H-36/11, 524H-T-36, 524H-T-36/11 Engines prior to Serial No.13820. B. Concurrent Requirements None C. Reason (1) Problem and Evidence There is a requirement to introduce new Full Authority Fuel Controller (FAFC) software with revised functionality including a new fan flutter Keep Out Zone (KOZ). In addition, an engineering review of the FAFC, based on in-service experience, has identified a number of areas where improvements in software may be made. (2) Substantiation The changes introduced by this Service Bulletin have been the subject of satisfactory verification testing by the unit manufacturer at both a software module level and a system level. The software timing savings have been validated using regression testing which concluded that there are no inadvertent functional changes affecting the software. Successful validation testing, including unit rig testing on the Rolls-Royce Systems Test Facility (STF), has taken place under both normal operating conditions and known failure conditions. FUEL AND CONTROL - FUEL CONTROLLER - INTRODUCTION OF A CONTROLLER WITH A REVISED STANDARD OF SOFTWARE ISSUE 17 - MOD.73-AG054Printed in Great Britain



# RB.211−73−AG054 Page 1 of 9 Mar.18/10 Jun.29/11 R(3) Objective Incorporation of this Service Bulletin is designed to upgrade the software standard and maintain unit reliability. (4) Effect of Bulletin on: (a) Operation Not affected (b) Maintenance Not affected (c) Overhaul Not affected (d) Repair Schemes Not affected (e) Interchangeability Not affected D. Description (1) This Service Bulletin covers the fitment to engines of an FAFC incorporating Aero Engine Controls Service Bulletin FAFC2000-73-7725, Initial Issue R dated Jun 22/10. (2) The software changes introduced by this Service Bulletin are: (a) Engine control behavior under conditions of dedicated generator drive or bearing failure has been found to be unacceptable when the rate of generator rundown is low or the resultant N3 signal is noisy. Currently, the control laws will respond to a sub-idle N3 signal by increasing fuel flow in a valid attempt to maintain the required idle speed. An N3 signal rate check is introduced to assist in the accommodation of dedicated generator failures. In addition, the N3 idle control schedule is revised to prevent a failing N3 signal resulting in a significant increase in fuel scheduling.Printed in Great Britain



# RB.211−73−AG054 Page 2 Mar.18/10 Jun.29/11 R(b) To avoid the possibility of encountering on-wing fan flutter whilst on the ground when the FAFC is in primary Engine Pressure Ratio (EPR) or alternate N1 mode of control, the commanded EPR or N1 must be restricted from stabilising in the fan flutter KOZ, defined by upper and lower limits. An automatic KOZ is introduced to prevent steady state operation in the fan flutter region. When enabled the KOZ prevents the EPR or N1 of the engine stabilising within the fan flutter region. (c) A recent event on an RB211 524G/H powered aircraft indicates that deteriorated engines, running with a high N1 at an EPR, could be thrust limited during climb with no indication other than a discrepancy on the pilots EPR gauge. During the event the discrepancy was reported as 0.02 EPR between two engines. Investigation confirmed that the limitation was caused by the N1 back-up control loop in the FAFC. The N1 back-up control loop exists to limit engine thrust should an EPR measurement error exist that causes a large difference between EPR command and measured EPR, resulting in the steady state control law increasing fuel. The back-up loop is set to limit N1 to the N1 reversionary command plus fixed offset. An offset is introduced to the N1 reversionary command that is a function of altitude. The setting of the offset ensures that low altitude flight regimes are unaffected and that increased margin to the back-up limitation is available to prevent EPR shortfall events at higher altitudes. (d) There has been one occurrence of an in-flight shut-down caused by an indicated high oil temperature (TOIL), due to a failure of the lane A oil temperature bulb. The oil temperature indication logic is designed to manage temperature bulb problems by recognising a discrepancy (the two lanes are more than 15 deg C apart) and choosing the signal closest to 100 deg C. The problem is attributed to an intermittent bulb fault, resulting in the logic incorrectly selecting the faulty signal. A TOIL rate check is introduced which is used in conjunction with the TOIL validation logic to ensure intermittent signals are detected and correctly accommodated.Printed in Great Britain



# RB.211−73−AG054 Page 3 Mar.18/10 Jun.29/11 R(e) During in-service operation, operators have suffered delays due to failed attempts at engine starting on extreme cold days (-27 deg C or below). Data from the events has shown that engines were operating at idle on the absolute minimum idle speed setting, 55 percent N3. The engine autostart abort occurred just as the affected engines were beginning to stabilise at idle, with the instantaneous speed at abort being just below 55 percent N3. The autostart hang/stall detection function is active up to 55 percent N3. Therefore, an engine about to stabilise at an idle speed close to 55 percent N3 can be misinterpreted as being about to stall and an autostart abort may occur. The upper limit for hang/stall detection is revised to ensure it is always at least 3 percent lower than the idle schedule in order to remove the possibility of operators experiencing an incorrect hang/stall when starting in extremely cold temperatures. (f) An engineering review of the software has shown that a single cycle High Pressure Shut Off Valve (HPSOV) microswitch transition from OPEN to CLOSED can cause incorrect fuel scheduling and cause the engine to hang. The revised software incorporates a fault integrator when the FAFC detects that the HPSOV microswitch has changed from one switch state to the other. When this transition occurs the fault integrator counts for four software cycles to confirm that the transition has genuinely occurred. This confirmation prevents the incorrect fuel scheduling. (g) A review of service operation has shown that the subject engines with autostart functionality enabled may suffer a large number of autostart related maintenance messages set, indicating failure to meet fuel-on conditions, particularly when no cross-bleed is available. The maintenance message is set if fuel-on conditions are not met within 65 seconds. The software is revised to increase the timer to 120 seconds. This increase allows the engine more time to satisfy the fuel-on conditions.Printed in Great Britain



# RB.211−73−AG054 Page 4 Mar.18/10 Jun.29/11 R(h) T20 measurement faults at engine start may cause nuisance P30 pipe leak messages, as the P30 model is a function of T20. Failure of the T20 signal, low but in range, will cause the P30 model to increase in value. If it increases by 40 percent then this will trip the P30 pipe leak logic. This results in the setting of maintenance message 7x808 ENG PNEUMATIC LINE FAIL and a DO NOT DISPATCH status message being set. During normal operation, the FAFC logic should be using the aircraft T20 value. When there is no agreement between the engine and aircraft values, the logic will select an engine value. In this situation, if the engine values disagree by more than 5K, then the lowest in-range value will be selected. The software is revised so that P30 pipe logic disables when engine T20 is selected (indicating that there is no agreement between aircraft and engine T20) AND the engine T20 values disagree by more than 15K. Analysis has shown that a 15K error will not cause the P30 pipe leak check to fail and hence errors less than this are acceptable. (i) The opportunity is taken to introduce timing savings in order to make the software more efficient and allow additional code to be implemented. (3) Existing units may be reworked in accordance with the vendor service bulletin. (4) Units incorporating this Service Bulletin will be identified by a new type number (see 2D). (5) The Boeing 747 Airplane Flight Manual (AFM) will require revision to disallow the use of take-off EPR at or below the upper fan flutter KOZ. The Boeing 767 AFM will not be revised at present. Take-off EPR in the fan flutter KOZ is not possible on the Boeing 767 because no aircraft are currently configured with fixed derate capability. E. Compliance ALERT This Service Bulletin must be accomplished on all engines by 31st December 2014. F. Approval The technical content of Service Bulletin 73-AG054 was approved by a representative of the European Aviation Safety Agency (EASA) on Mar.10/10, EASA certificate No.10029185.Printed in Great Britain



# RB.211−73−AG054 Page 5 Mar.18/10 Jun.29/11 RThis Service Bulletin has been reviewed by the Federal Aviation Authority (FAA) and the repairs and modifications herein comply with the applicable Federal Aviation Regulations (FAR(s)) and are FAA approved. This Service Bulletin has been approved by the Boeing Commercial Airplane Company. G. Manpower Refer to Aero Engine Controls Service Bulletin FAFC2000-73-7725, Initial Issue R dated Jun 22/10. H. Material Price and Availability Refer to Aero Engine Controls Service Bulletin FAFC2000-73-7725, Initial Issue R dated Jun 22/10. I. Tooling Price and Availability Refer to Aero Engine Controls Service Bulletin FAFC2000-73-7725, Initial Issue R dated Jun 22/10. J. Weight and Balance (1) Weight Change None (2) Moment Arm No effect (3) Datum Power Plant Station (PPS) 100 K. References (1) Refer to Aero Engine Controls Service Bulletin FAFC2000-73-7725, Initial Issue R R dated Jun 22/10. (2) This Service Bulletin is subsequent to the following Rolls-Royce RB211 Service Bulletin: 73-D435 Fuel and control - Fuel controller - Introduction of a controller with revised standard of software (TRW Lucas SB FAFC2000-73-7543). (3) Engine Manual, 72-00-34, Removal and InstallationPrinted in Great Britain



# RB.211−73−AG054 Page 6 Mar.18/10 Jun.29/11 R(4) Aircraft Maintenance Manual, Removal/Installation L. Other Publications Affected For effect on Illustrated Parts Catalogue (IPC) refer to 2. Material Information. M. Interchangeability of Parts Not affectedPrinted in Great Britain



# RB.211−73−AG054 Page 7 Mar.18/10 Jun.29/11 R2. Material Information A. The kit required consists of the following parts: None B. Parts to be reworked: None C. New production parts: The following parts will be made available as future spares: None. D. Vendor units affected: The following unit type number changes have been allocated to identify units embodying the features of this Service Bulletin: All Engines 73-21-09 FIG ITEM NO. NEW PART NO. QTY PART TITLE MAT OLD PART NO. INSTR DISP

01350 FAFC2000 -11BK5 1 .Control, fuel (VU4287) - FAFC2000 -11BJ5 (1) 01350 FAFC2000 -12BK6 1 .Control, fuel (VU4287) - FAFC2000 -12BJ6 (1)
E. Instruction disposition codes: (1) Old and new parts are freely and fully interchangeable.Printed in Great Britain



# RB.211−73−AG054 Page 8 Mar.18/10 Jun.29/11 R3. Accomplishment Instructions A. The revised Full Authority Fuel Controller (FAFC) software introduced by this Service Bulletin is interchangeable with the existing. Remove existing and install new in accordance with current overhaul or maintenance procedures (Engine Manual, 72-00-34, Removal and Installation or Aircraft Maintenance Manual, 73-21-13, Removal/Installation).
B. For rework of the existing FAFC, refer to Aero Engine Controls Service Bulletin FAFC2000-73-7725, Initial Issue R dated Jun 22/10.
C. A record of accomplishment is required.Printed in Great Britain



# RB.211−73−AG054 Page 9 Mar.18/10 Jun.29/11 RAERO ENGINE CONTROLS SHAFTMOOR LANE HALL GREEN BIRMINGHAM B28 8SW ENGLAND TELEPHONE: 44 121 707 7111 FAX: 44 121 707 8826



### TRANSMITTAL 

# FAFC2000-73-7725 Page 1 of 2 Jun 22/10
©2010 Rolls-Royce Goodrich Engine Control Systems Limited 

### 301430 

## FULL AUTHORITY FUEL CONTROL TYPE: FAFC2000 ATA REF 73-21-09

THIS PAGE TRANSMITS THE INITIAL ISSUE OF SERVICE BULLETIN FAFC2000-73-7725 Please note the Company name has changed from Goodrich Engine Control Systems to Aero Engine Controls. Reason for issue This service bulletin (modification) introduces the approved main processor software (known as issue 17). Action Keep this SB with the Component Maintenance Manual. Put in this SB Transmittal page and the SB pages 1 thru 8 dated Jun 22/10.

APPROVED FOR AERO ENGINE CONTROLS 

# SERVICE BULLETIN TRANSMITTAL

Signed: Date: 22nd June 2010

### Aero Engine Controls

TRANSMITTAL 

# FAFC2000-73-7725 Page 2 of 2 Jun 22/10
©2010 Rolls-Royce Goodrich Engine Control Systems Limited 

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# FAFC2000-73-7725 Page 1 of 8 Jun 22/10
©2010 Rolls-Royce Goodrich Engine Control Systems Limited 

## Aero Engine Controls 

# SERVICE BULLETIN
ENGINE FUEL AND CONTROL - CONTROL - FULL AUTHORITY FUEL CONTROL TYPE FAFC2000 INTRODUCTION OF APPROVED MAIN PROCESSOR SOFTWARE ISSUE 17 1. Planning Information

A. Effectivity Full Authority Fuel Control (FAFC), Types: FAFC2000-11-BJ-5, FAFC2000-12-BJ-6. NOTE: This Service Bulletin can also be applicabl e to FAFC types with previous issues of approved main processor software. B. Concurrent Requirements None C. Reason (1) Problem It is necessary to make changes that will improve the current version of control software in the Full Authority Fuel Control (FAFC). (2) Substantiation The changes introduced by this Service Bulletin (modification) have had satisfactory verification and validation tests. (3) Objective Incorporation of this Service Bulletin (Modification) will improve the current software standard and maintain the FAFC reliability. D. Description This Service Bulletin introduces new approved ’Flight Release’ main processor software into the FAFC. The new software (Issue 17) has changes which makes necessary functional enhancements, corrections and vari ous improvements to the current FAFC software. The new software identity is: Main processor (Lanes A and B): Remote processor (Lanes A and B): EEPROM data file: FAF1MU50B.GRP FAFCRU27A.GRP (Current) FAFEEP90A.DAT

# FAFC2000-73-7725 Page 2 of 8 Jun 22/10
©2010 Rolls-Royce Goodrich Engine Control Systems Limited 

## Aero Engine Controls 

# SERVICE BULLETIN The main processor software is stored in the D07 and D08 Computer assemblies. When the accomplishment instructions (para. 3.) have been done the FAFC type number changes as follows:

E. Compliance Do this Service Bulletin (modification) to in-service and repair FAFC units as agreed with Rolls-Royce plc. F. Approval The technical content of this Service Bulletin has been approved as part of Rolls-Royce Service Bulletin 73-AG054. G. Manpower At workshop visit: Program and recertify the FAFC only - 10 hours. H. Weight and Balance No Change. I. References FAFC2000 Component Maintenance Manual (CMM) (73-21-09). DCU 1026 Production Acceptance Test Rig (ET 597109) Ground E quipment Manual (GEM). Rolls-Royce RB211 Service Bulletin 73-AG054. J. Other Publications Affected FAFC2000 Component Maintenance Manual (CMM) (73-21-09) Testing and Troubleshooting and the Illustrated Parts List Sections. 2. Material Information A. Material - Price and Availability The cost of the parts and manpower to accomplishthis Service Bulletin will be charged to the operator. B. Tooling - Price and Availability If applicable a supplement to this service bulletin will be issued later. FAFC2000-11-BJ-5 FAFC2000-12-BJ-6 Becomes Becomes FAFC2000-11BK5 FAFC2000-12BK6

# FAFC2000-73-7725 Page 3 of 8 Jun 22/10
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## Aero Engine Controls 

# SERVICE BULLETIN C. Material Necessary for Each FAFC The consumable items necessary to do the accomplishment instructions are given in the related CMM. Some of the items necessary can be supplied in a kit as follows (the equivalent alternatives can be used for the items shown):

NOTE: To get the software kit necessary to do the accomplishment instructions for this Service Bulletin send a Purchase Order to one of the addresses that follow (or use one of the E-mail addresses that follow): AMERICAS Spares Service Desk Customer Services America 4115 Corporate Center Drive Monroe North Carolina 28110-1313 USA Telephone: +1 704-282-2545 Fax: +1 704-238-8533 E-mail: cs.spares@goodrich.com Part Number Qty/ FAFC Description Instruction Note No. 86611121 Software Modification Kit You only need to order one kit but you must give the quantity of FAFC to be changed. The software modification kit includes: FAFC2000-73-7725 Copy of this service bulletin 86611108 CD-ROM (new Control and Test files) 1 86620040 1 Unit label (-11BK5) 2 86620040 1 Unit label (-12BK6) 2 77765463 4 D07/D08 assembly label 2 77769766 16 IC adhesive cover 2 Instruction Notes 1 Copy the CD-ROM files onto the DCU 1026 Production Acceptance Test Rig (ET 597109). The CD will automatically copy the files to their correct directories. Make a folder icon for the new type numberand rename shortcut icons for the new test files. Reboot the computer. 2 Discard and attach new item

# FAFC2000-73-7725 Page 4 of 8 Jun 22/10
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## Aero Engine Controls 

# SERVICE BULLETIN EUROPE, MIDDLE EAST, and AFRICA Spares Service Desk Customer Services Europe, Middle East and Africa Stratford Road Solihull B90 4LA UK Telephone: +44 (0)121 451 5851 Fax: +44 (0) 121 451 5949 E-mail: cs.europe@Goodrich.com ASIA/PACIFIC Spares Service Desk Customer Services Asia Pacific Customer Services Goodrich Control Systems Pte. Ltd. 39 Changi North Crescent Singapore 499642 Telephone: +65 6543 7233 Fax: +65 6542 7236 E-mail: ap.spares@Goodrich.com D. Changed Parts The parts that can be changed and their new part numbers after the change are as follows:

Instruction Note(s): 1. Do the change and identify the part with the new part number. 3. Accomplishment Instructions The accomplishment instructions must be done by an authorised Maintenance, Repair and Overhaul Facility. To put the new software into the FAFC do the tests and procedures that follow. Refer to the CMM, Testing and Troubleshooting section unless other sections in the CMM are given. New Part Number Qty/ FAFC Description Old Part Number Instruction Note No. 86634895 2 D07 Control Computer Assembly (Pre SB 7256) 86628598 1 86634894 2 D07 Control Computer Assembly (Post SB 7256) 86628597 1 86634897 2 D08 S/M Computer Assembly (Pre SB 7257) 86628600 1 86634896 2 D08 S/M Computer Assembly (Post SB 7257) 86628599 1

# FAFC2000-73-7725 Page 5 of 8 Jun 22/10
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## Aero Engine Controls 

# SERVICE BULLETIN A. Pre-Programming Procedure (1) Do the Prepare for the Test Procedure. (2) Do the Fault Code Store Extract and Translate procedures. (3) Remove the two D07 and the two D08 computer assemblies from the FAFC (refer to the CMM, Disassembly section). (4) Do the D07/D08 Preparation procedure and the Program Erasure procedure to the two D07 and the two D08 computer assemblies (refer to the CMM, Testing and Troubleshooting section). B. Programming Procedure (1) Do one of the two Programming procedures that follow: (a) ROM 3000 Prommer 1 Do the Programming Procedure to install the new software into the D07 & D08 assemblies (refer to the CMM, Testing and Troubleshooting section). NOTE: In the NOTE in step 3. E. 3. of the Programming Procedure the first pair of checksums must be 29E5 and the second pair 5C16. (b) Lloyds ONBP 100 Board Programmer NOTE: This is the preferred method of programming the software. 1 Make sure that the necessary software files are loaded in the Lloyds ONBP 100 Board Programmer. 2 Make sure the adaptor applicable to the D07 (adaptor AD017) or D08 (adaptor AD018) card is installed to the Lloyds ONBP 100 Board Programmer. 3 Energise the Lloyds ONBP 100 Board Programmer and the PC. 4 When the PC has booted up select ONBP100 from the desktop. 5 The PC will prompt you for a password. WRITE operator The VDU will show the version of the Programmer Firmware. NOTE: If you do not see the correct version of Programmer Firmware change it by use of the Lloyds Research Programmer Help File. 6 When the device table has loaded the VDU will show ’Programmer Connected’. NOTE: If you do not see the message ’Programmer Connected’ you can get communication errors.

# FAFC2000-73-7725 Page 6 of 8 Jun 22/10
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## Aero Engine Controls 

# SERVICE BULLETIN

7 Select File. 8 Select Open Job and select the necessary Job File (refer to Checksum Table below). 9 Select Open. 10 Select Load Job, followed by Run Job. 11 When the files are downloaded to the programmer, select OK. 12 Make sure that the File Checksums are correct (refer to the Checksum Table below). 13 Select Load Job, Choose Device. 14 Select the device 27C256 Intel. 15 Select OK. 16 Before you install the card in the programmer do a check of the card connector and the adaptor connector. Make sure the pins are correct and not damaged. 17 Install the card in the programmer adaptor. Use the top plate to secure the card. 18 Select Program, Program. 19 When Programming is complete the applicable Board Checksum will be shown (refer to the Checksum Table below).

20 Select OK. 21 Use the hinged plate to remove the card from the programmer adaptor. 22 Do again paras (16) thru (21) for the next card of the same type, when both cards of the same type have been programmed, do para (23) 23 Do again paras (1) thru (22) for next card type to be programmed, when the two D07 cards and the two D08 cards are programmed do para (24). Board Job File File Name File Checksum Board Checksum D07 D07_FMU150B.LRJ FRU150B.ABS FRU150B.AB1 68C3 5D28 00EF85FB D08 D08_FMU150B.LRJ FRU150B.ABS FRU150B.AB1 68C3 5D28 00EF85FB

# FAFC2000-73-7725 Page 7 of 8 Jun 22/10
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## Aero Engine Controls 

# SERVICE BULLETIN C. Post Programming Procedure (1) Do the Assembly Completion Procedure (refer to the CMM, Testing and Troubleshooting) to the two D07 and the two D08 assemblies. (2) Install the two D07 and the two D08 assemb lies into the FAFC (refer to the CMM, Assembly). (3) Do the Install New Trim Files in the D08 procedure (refer to the CMM, Testing and Troubleshooting). Use the software files that follow:

(4) Do the Standard Serviceability Test Schedule procedure (refer to the CMM, Testing and Troubleshooting). Use the changed software files that follow:

(5) Attach a new Unit Label marked with the new unit type number (i.e. FAFC2000- 11BK5 or FAFC2000-12BK6, new main processor software file (50B), existing remote processor software file (27A) and the EEPROM data file (90A).

Main Symbol Table: FMU150B EEPROM Trim: UPD90A Trim File Verification: VER90A.

Main Symbol Table: FMU150B Lane A and B Main Software: FAF1MU50B Y59F1 Automatic Test Program: Y59F139B Y59F2 Automatic Test Program: Y59F232B Y59F3 Automatic Test Program: Y59F335B

# FAFC2000-73-7725 Page 8 of 8 Jun 22/10
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## Aero Engine Controls 

# SERVICE BULLETIN

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