Lesson plan Line and Base Maintenance CFM56-7B 航线和基地维护
**** Hidden Message ***** Issue: 4/9/20111
Lesson plan
Line and Base Maintenance
CFM56-7B
Issue: 4/9/2011
welcome 2
Ouverture de la salle
• Accéder au disk K/users/common/LB-7/présentation Line and base
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3
WELCOME
• Welcome and introduce the instructor
• introduce this site
• CFMI introduction
• Fill in the form
• Timing
• “LUNCH TIME”, price ticket and menu
• Restaurant présentation
• Final review of the sign in sheet
• Collect the “sign in sheets” (les feuilleter et faire un petit commentaire
sur les élèves présents à la cession).
• A quick look around the training center
welcome CFM56-7B LINE AND BASE MAINT. OULINE
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CFM56-7 LINE & BASE COURSE OUTLINES
1. Maintenance Documents
2. Power Plant General (71)
3. Engine Exhaust (78)
4. Engine General (72)
5. Fuel and Control System (73) (SAC)
5. Fuel and Control System (DAC)
5. Engine Electrical Wiring Harnesses
6. Air System (75)
7. Ignition System (74)
8. Start System (80)
9. Oil System (79)
10. Engine Indicating System (77)
11. Engine Fault Isolation - CDU Messages
71-00-00 POWER PLANT - INTRODUCTION
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72-00-00 ENGINE DATA PLATE 5
ENGINE RATINGS AND APPLICATIONS
Engine 7B18 7B20 7B22 7B24 7B26 7B27
Rating 19.500 20.600 22.700 24.200 26.300 27.300
737 Aircraft 600 600 600 inst. Note:
700 700 700 700 (next 7B40)
800 800 800
900 900 900
BBJ
C40A
•CFM56-7B can be used at all thrust ratings: from 19.500 to 27.300 lbs.
•Fits all 737 aircraft models and meets customer needs.
•Bump option available on highest thrust: 22, 24 and 27
•Identified by B1 at end of model: example 7B22B1
Bump
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ENGINE - INTRODUCTION
72-00-00
ENGINE DATA PLATE
• On right of the fan case, aft. of oil tank
– Multi entry name plate: allows to reidentify engine thrust category per BMM
Data plate Shows: Regulatory agency data / Eng. perf. / manufact. data;
– model = CFM56-7B
– serial number = 779835
– certification type = DGAC and FAA N°
– Configuration = -7B24 (SAC or DAC and bump option)
– T.O. THRUST rating = daN and LB (24200 LB)
– MAX CONT THRUST = daN and LB
– N1 TRIM modifier = 0 to 7
– Inspection stamp / Manufacturer / Production codes and date
– SERV. BUL. = configuration change SB N°
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71-00-00 ENGINE COWLINGS 7
POWER PLANT - INTRODUCTION
• Boeing 737 NG equipped with CFM56-7B ENGINE FAMILY
• The Power plant includes the engine plus:
– Cowling / Wiring harnesses / Mounts / Vents and drains
• CFM56-7B provides thrust for the A/C and power for
• Electrical
• Hydraulic systems
• Pneumatic
• CFM56-7B high bypass turbo fan engine
– ratio: 5.1 / 1 for the 7B27 (5.1 to 1)
– ratio: 5.6 / 1 for the 7B18 (5.6 to 1)
– DUAL ROTOR
– FADEC ENGINE (Full Authority Digital Electronic Control)
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71-00-00 HAZARD AREAS 8
ENGINE COWLINGS
• Provide smooth aerodynamic surfaces and protective area for C&A
• Cowlings :
– INLET COWL
• T 12 access door (RHS)
• Ram air inlet for EEC cooling
– FAN COWLS
• IDG access door (LHS)
• Chip detectors access door (LHS) / Pressure relief door
• Oil tank access door (RHS)
• Vortex control device on the inboard fan cowl
– the THRUST REVERSER (that will be detailed latter)
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71-00-00 ENGINE DRAINS 9
ENGINE HAZARDS
• Stay out of the inlet and exhaust area while the engine is in operation
• Hazard areas:
– INLET SUCTION 13 ft (4 m) around the inlet at IDLE POWER
• WARNING IF WIND IS OVER 25 KNOTS, AREA INCREASED BY 20%
– EXHAUST (Gas, Air jet Heat and velocity), 45° from the rear of the engine
or // to the wing
– ENGINE NOISE (Hear protection)
• Access corridor defined in between the inlet and exhaust limits
– No access permitted above low idle speed.
– Safety HARNESS or lanyard to USE during idle leak check .
– Verbal communication with the Cockpit crew
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71-00-00 ENGINE DRAIN MAST 10
ENGINE DRAINS
• DRAINNING
– Prevent fluid contact from engine hot areas
• Draining for Oil, fuel, hydraulic, water and vapors.
• Used to detect component failure
• See chapter 71-71-00 for all permissible limits.
• DRAIN LINES location (Inst. Note: describe the drain ports with the
help of the slide)
– RIGHT FAN COWL
• Through the starter air discharge duct for most of the fuel and air system
components (Inst. Note: more details next slide)
• And the oil tank scupper drain
– LEFT FAN COWL
• Through 2 holes for fuel pump and IDG / Hydraulic pump
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ENGINE DRAINS
• Drain mast identification : (Inst. Note: refer to the slide)
• Vue Aft. Looking Forward
71-71-00 LEFT FAN COWL DRAINS
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LEFT FAN COWL DRAINS
• Drains identification (Inst. Note: refer to the slide)
– Fuel pump
– IDG
– Hydraulic pump
71-71-00 RIGHT FAN COWL DRAINS
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RIGHT FAN COWL DRAINS
• Oil tank scupper drain identification (Inst. Note: refer to the slide)
– Rearward the left igniter box
71-71-00 FAN COWLS
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71-11-00 POWERPLANT ELECTRICAL HARNESSES 14
FAN COWLS
• 3 HINGES (quick attach/detach ball pins) attache Each fan cowl to
strut
• 3 LATCHES secure cowls (inst note: open/close in any order)
• 2 telescopic HOLD OPEN RODS by fan cowl.
– Both ends attached to fan cowl when closed
– Lower end connected to engine when opened
• Red lock indication when hold open rod locked (yellow at the training)
• Do not open above 40 Knts wind
fan cowls made of aluminium,
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71-00-00 15
instr. note: No fire bottles up here
(Located in the LH wheel well)
Hydraulic
Starter
Fuel
left side Fan cowl
POWERPLANT - ELECTRICAL HARNESSES
• ELECTRICAL
– Electrical connectors accessible on both sides of the Fan cowl support
beam.
• FUEL, OIL, AIR
– Most Connections available on the left side Fan cowl support beam, some
on the right hand side.
POWER PLANT - ENGINE MOUNTS
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71-00-00 16
POWER PLANT - ENGINE MOUNTS
• Fwd engine mount on the fan frame
attached to the strut
• Aft engine mount on the turbine frame
• Thrust bars from the aft mount to the fan frame
ENGINE EXHAUST SYSTEM
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CFM56-7 LINE & BASE COURSE OUTLINES
1. Maintenance Documents
2. Power Plant General (71)
3. Engine Exhaust (78)
4. Engine General (72)
5. Fuel and Control System (73) (SAC)
5. Fuel and Control System (DAC)
5. Engine Electrical Wiring Harnesses
6. Air System (75)
7. Ignition System (74)
8. Start System (80)
9. Oil System (79)
10. Engine Indicating System (77)
11. Engine Fault Isolation - CDU Messages
78-00-00 EXHAUST SYSTEM - INTRODUCTION
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ENGINE EXHAUST SYSTEM
• Engine exhaust system has 2 subsystems:
– Turbine exhaust system
– Thrust reverser system
78-00-00 EXHAUST SYSTEM - GENERAL DESCRIPTION
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78-00-00 19
EXHAUST SYSTEM - GENERAL DESCRIPTION
• Thrust reverser + Nozzle and Plugs:
– Control direction of turbine and fan air exhaust gases
– Increases air velocity to provide engine thrust
– In deploy position, the fan air discharge goes out radially and forward
– The turbine exhaust gases do not change during deploy
• T/R Used during landing and rejected T/O
(Ground use only / Not for power backing)
• each T/R has: a right and a left half
– Each half has a translating sleeve which moves aft (deploy)
– Sleeves work independently from each other
TURBINE EXHAUST SYSTEM
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78-11-00 TR Component location 20
TURBINE EXHAUST SYSTEM
• Inlet airflow ducted into 2 airflows by the splitter fairing as:
– Primary airflow
– Secondary airflow
• PRIMARY EXHAUST PARTS
– Exhaust nozzle (outer edge of turbine exhaust flow)
– Exhaust plug (inner edge of turbine exhaust flow)
• FAN AIR EXHAUST (secondary)
– Air discharge ducted in between exhaust nozzle and TR sleeves
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THRUST REVERSER - COMPONENT LOCATION
• TR have 2 halves
• MAIN COMPONENTS on each halve
– 3 translating sleeve actuators
– 4 hinges attach each T/R half to the strut
– 6 tension latches to hold the T/R halves together
– 1 opening actuators to open the T/R half
– 2 deactivation points for flight dispatch
– 3 doors to get access to translating actuator ends
T/R MAINTENANCE DEACTIVATION
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78-31-00 T/R OPENING ACTUATOR 22
T/R TENSION LATCHES
• 6 tension latches at the bottom of each T/R
– Hold the T/R halves
– #1 at the front of the TR / #6 at the rear
– Latches are interchangeable
• OPENING /CLOSING T/R
– Open latches from aft #6 to front #1
– Close latches from front #1 to Aft #6
OPEN
CLOSE
1 6
1 6
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T/R OPENING ACTUATOR
• 1 opening hydraulic actuator per half on fwd face of T/R cowl.
ACCESS: Open the fan cowl / L/E flaps and slats must be retracted / Wind
velocity < 40 knots
WARN.: Make sure the T/R deactivation procedure has been done (AMM)
• usually hand pump used to operate T/R opening actuator rod
– Hand pump connected to an inlet fitting at the end of opening actuator rod
– Manual procedures exist also
WARN.: If manual procedure repeatedly used,
open regularly the T/R with the hand pump for hydraulic recycling.
• Lock collar moves into lock position as rod extends.
CAUTION: a CLICK SOUND and a RED BAND on rod confirms lock.
• ACTUATOR LOCK must be installed for maintenance tasks
– 45° and 55° opening is possible (refer to BMM)
– The lock collar must be moved up before you lower the T/R cowl.
T/R CONTROL SYSTEM - SYNC. LOCK
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T.R. CONTROL SYSTEM - SYNC LOCK
• 2 purposes:
– Locks the sync. Shafts when no T/R deploy signal
prevent hydraulic actuators operation
– Manual drive the hydraulic actuators to desengage the lock mechanism
• Sync lock attached to head end of lower hydraulic actuator on each T/R
half
• Sync lock requires electrical power to operate during T/R operation
–Without electrical power sync lock are in lock position
– During T/R operation internal solenoide energizes and clutch desengages
and hydraulic actuators can operate
• Sync lock Manual drive use: always respect BMM procedure
– Square drive tool pushes a small pin inside the connector and desengages
clutch.
78-34-00 T/R SLEEVE LOCK PROXIMITY SENSOR
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TR / Hydraulic actuator / functionnal description
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T/R SLEEVE LOCK PROXIMITY SENSOR
• T/R Sleeve lock proximity sensor on head end of T/R locking actuator
– Each locking actuator has a sleeve lock proximity sensor
– One sensor for each T/R translating sleeve
• Supplies lock and unlock signal to the EAU (Engine Accessory Unit) for
T/R operation control and fault isolation
78-34-00 T/R DEACTIVATION FOR FLIGHT DISPATCH
MORE DETAILS SEEN IN INDICATING
CONCERNING FAULT ANNUNCIATION
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78-36-00 27
T/R INDICATING SYSTEM
• LVDT measures sleeve position and sends data to the EEC
LVDT = Linear Variable Differential Transducer
• EEC sends this data to the DEU
• LVDT data can be seen on CDU (input monitoring and faults)
• DEU uses LVDT data to control the rev. message on CDS
– above N1 speed indicator:
• The “REV” message is amber when a sleeve is 10 to 90% to deploy position
• The “REV” message is green when sleeve is more than 90% to deploy
– “REVERSER” amber light comes on P5 panel:
• During normal stow operation for 10.5 seconds
• Stays on if :
– T/R control system fails during stow
– T/R component fails immediately during deploy or stow operation:
Proximity sensor, Sync. lock, Directional control valve, Hydraulic isolation valve.
• Light stays on until you fix the problem and reset the EAU (Engine Accessory Unit)
– “ENGINE CONTROL” amber light comes on when a serious failure of the
engine or the T/R LVDT happens = NO DISPATCH
T/R INDICATING
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T/R INDICATING SYSTEM - REVERSE MESSAGE
• EEC Ch A and Ch B calculate sleeve position from the LVDT inputs
– EEC usually uses an average of the two values in its logic to show the
message
– EEC changes analog signal to digital
– EEC sends data to CDS/DEU for message display
• Amber message “REV” when one or both sleeve >10% and <90%
deploy
• Green message “REV” when both sleeves >90% deploy
• EEC has also the LVDT failure logic:
– “ENGINE CONTROL” amber light and master caution come on, when
conditions are met.
78-36-00 T/R LEVER INTERLOCK SOLENOIDS
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76-00-00 29
T/R INTERLOCK SOLENOIDS
• 2 Interlock Solenoids energize to permit full reverse thrust lever motions
– Solenoid operates an interlock latch through a rod
• When you move the Reverse TL into DEPLOY position, a contour on a brake
mechanism catches the latch and stop the rotation of the brake mechanism
– Limits the travel of reverse thrust levers until EEC sees both translating
sleeves more than 60% to deploy position (using LVDT signal; see page 63)
– EEC energizes the TR Interlock Solenoids and latches desengage when the
TR sleeves are in the DEPLOY position
• Instr. Note:
– 5 T/R lever positions :
• Stow - Idle detent = interlocks stops - Detent 1 - Detent 2 - Maxi reverse
– reverse thrust cannot increase until EEC sees sleeves at 70% deploy
– Full reverse thrust cannot occur until sleeve passed 90% deploy
– Second use of LVDT - reverse thrust lever locking and reverse thrust control
ILCBT - EEC CONTROL LIGHT
TR sequence
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T/R INDICATING - LVDT
• LVDT supply T/R sleeve position data to EEC Ch. A and B
• Feedback rod of locking actuator moves the LVDT ’s armature
assembly as the T/R sleeve deploys or stows
• EEC uses LVDT signal for:
– Engine forward and reverse thrust control
– Thrust lever interlock control
– Control the REV message on CDS
– Control « ENGINE CONTROL » light
– LVDT failure isolation through CDU
78-36-00 T/R INDICATING SYSTEM - REVERSE MESSAGE
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TR indicating systeme / reverser message
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TR indicating system / CDU
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78-34-00 T/R TENSION LATCHES 33
T/R MAINTENANCE DEACTIVATION / control valve
• 2 T/R Control Valve Modules
– 1 in the LH wheel well of the a/c
– 1 in the RH wheel well of the a/c
• T/R control valve modules control
hydraulic power to T/R hydraulic actuators
• DEACTIVATION FOR MAINTENANCE (Mandatory)
– Manual isolation valve handle located on T/R control valve
– Once the handle is on the deactivation position,
install a Lock pin to secure the handle in the lock position
WARNING: Before removing the pin, Translating cowls positions must agree
with T/R lever position in the cockpit.
CAUT: Do not use only this deactivation for flight dispatch
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T/R - DEACTIVATION FOR FLIGHT DISPATCH
CAUTION: FOLLOW FLIGHT DISPATCH PROCEDURE from BMM
• 2 deactivation points for each translating sleeve
• Install 2 pins to deactivate the T/R for aircraft dispatch
– Rubber plugs are at the holes where you install pins
– Pins are usually part of the fly away kit
• Pins prevent movement of translating sleeve
• Install warning flag on TLA
78-31-00
END OF POWER PLANT
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CFM56-7 LINE & BASE COURSE OUTLINES
1. Maintenance Documents
2. Power Plant General (71)
3. Engine Exhaust (78)
4. Engine General (72)
5. Fuel and Control System (73) (SAC)
5. Fuel and Control System (DAC)
5. Engine Electrical Wiring Harnesses
6. Air System (75)
7. Ignition System (74)
8. Start System (80)
9. Oil System (79)
10. Engine Indicating System (77)
11. Engine Fault Isolation - CDU Messages
72-00-00 ENGINE - INTRODUCTION
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72-00-00 36
ENGINE - INTRODUCTION
• Engine supplies:
– Thrust to the airplane
– Electric / hydraulic / pneumatic power to the systems
MAIN ENGINE BEARINGS
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72-00-00 37
GENERAL DESCRIPTION
• High by-pass ratio / Dual rotor
• 61 in. (1,55 m) FAN dia.
• Basic dry weight 5257 lbs (2385 kg)
• Fan and booster: 4 stages LPC on compressor shaft N1
– Splitter fairing divides the fan blade air discharge into 2 airflows:
• primary supplies the HP engine module
• secondary through fan ducts supplies 80% of the thrust during take off
• 9 stage HPC linked on compressor shaft N2
– increases air pressure to supply combustor
– supplies also bleed air for a/c and engine pneumatic systems
• Combustor mixes air and fuel and ignition for gase burn
– Supply hot gases to the HPT
• 1 stage HPT turns the HPC and accessory drive
• 4 stage LPT turns the Fan and booster
• N2 drives accessory gearbox:
– Inlet gearbox / Radial drive shaft / Transfer gearbox / Horizontal drive shaft
ACCESSORY GEARBOX (AGB) MODULE
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72-00-00 38
MAIN ENGINE BEARINGS
• 2 main frames: fan frame / LPT frame
• Main bearings held in 2 vented sumps
– fwd sump in the fan-frame = location for # 1, 2 and 3 bearings
– rear sump in the LPT frame = location for # 4 and 5 bearings
• 5 Main bearings
– # 1 ball bearing controls axial loads (thrust) of fan and booster
– # 2 roller bearing controls radial loads of fan and booster
– # 3 double bearing:
• 1 ball bearing controls axial loads (thrust) of HPC
• 1 roller bearing controls radial loads of HPC
– # 4 roller bearing = INTERSHAFT Bearing, controls radial loads of the HPT
– # 5 roller bearing controls radial loads of the LPT
• Bearings hold N1 / N2 rotors which turn independently
GENERAL DESCRIPTION
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Engine Flanges
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72-00-00 40
- LAST OF ENGINE
- NEXT: GO TO SHOP
ENGINE AERODYNAMIC STATIONS
• Aerodynamic stations identify areas of air pressure and temperature
– Station 0 - ambient air for fuel metering logic in case of loss of ADIRU data
– Station 12 - fan inlet (T12) for thrust management - no more PS12 and T2
– Station 13 - fan air discharge - (option health monitoring - PMUX)
– Station 25 - HPC inlet Temp. for fuel metering logic (P for optional PMUX)
– Station 30 - HPC discharge air pressure for fuel metering logic
– Station 49.5 - stage 2 low pressure turbine stator for EGT
– Station 50 - low pressure turbine air discharge - (PMUX option)
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ACCESSORY GEARBOX (AGB) MODULE
• AGB on the left hand side of the engine
– AGB driven by N2 through RDS and TGB
– AGB drives a/c and engine accessories
• AGB holds and operates Airplanes and Engines Accessories
– Accessories on front face AGB
• EEC alternator
• Hand cranking pad turns N2 for borescope inspection
• N2 speed sensor
• Engine air starter
• Integrated Drive Generator (IDG)
• Hydraulic pump
– Accessories on rear face AGB
• Fuel package: fuel pump / HMU / main oil fuel heat exchanger / SFH
• Lubrication unit
• Scavenge oil filter
FAN BLADES AND SPINNERS
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FAN BLADES AND SPINNERS
• Front and rear spinners direct inlet airflow of engine
– They are aerodynamic fairings designed to reduce FOD in primary airflow
– Rear spinner holds trim balancing screws
• 24 solid titanium wide chord fan blades - LRU
– Cautions for fan blade removal:
• Before fan blade removal, record position and S/N to keep the in balance
condition after reinstallation
• Offset holes on spinners, retainers and fan disk allow only 1 mount pos.
• spherical index (imprint) on rear spinners correspond to offset holes
• If you replace fan blades, calculate moment weight distribution
– Replace pair(s) of blades
• You read P/N, S/N and moment weight on the root of the fan blades
– Retainer flange holds platforms and center the rear spinner
– Retainer ring holds spacer shims and participate to blade retention
– Platform engage in pins of fan disk
ENGINE AERODYNAMIC STATIONS
Fan blade
change
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Spinner cone balance weight
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GO TO SHOP - ENGINE
– Show hazard areas - warning !
– Describe cowlings - T/R - exhaust
– Doors: IDG - chip detect. - Oil tank - T12
– Show holes/starter discharge for drains
– Open fan cowls - hold open rod: safety collar
– Show electrical harnesses to strut
– Locate T/R opening actuator
– Open T/R: - latches #6 to #1- use hand pump
• Remind students about: T/R deactivation actuator lock / check L/E flaps retracted
• warning: listen CLICK for safety collar!
– Describe T/R components
– Show engine mounts - nameplate - engine modules - AGB & accessories -
spinners and fan blades
OBJECTIVES: DESCRIBE POWER PLANT/ENGINE AS MECHANIC DISCOVERS
IT (FROM “OUTSIDE” TO “INSIDE”) - OPEN THE COWLS
72-00-00 ENGINE FUEL & CONTROL - INTRODUCTION
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CFM56-7 LINE & BASE COURSE OUTLINES
1. Maintenance Documents
2. Power Plant General (71)
3. Engine Exhaust (78)
4. Engine General (72)
5. Fuel and Control System (73) (SAC)
5. Fuel and Control System (DAC)
5. Engine Electrical Wiring Harnesses
6. Air System (75)
7. Ignition System (74)
8. Start System (80)
9. Oil System (79)
10. Engine Indicating System (77)
11. Engine Fault Isolation - CDU Messages
FUEL AND 73-00-00 CONTROL SYSTEM - INTRODUCTION
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73-00-00 46
GENERAL DESCRIPTION
ENGINE FUEL & CONTROL - INTRODUCTION
• DISTRIBUTES and CONTROLS FUEL for:
• COMBUSTION
• AND SERVO SYSTEM OPERATION
• 3 SUBSYSTEMS:
• DISTRIBUTION
• ENGINE CONTROL
• INDICATING
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73-00-00 47
FUEL AND CONTROL - GENERAL DESCRIPTION 1/2
• EEC the “brain” of the engine
• HMU the “muscle” of the engine
• EEC alternator is the primary electrical power supply
– a/c transfer buses are another power supply when N2<12% or cockpit command
• EEC receives commands from airplane systems and components
• EEC receives primary air pressure and temperature data from the ADIRU
• TLA resolver supplies engine thrust commands to EEC
• EEC receives operating data from engine sensors
• EEC controls the engine ignition system
• EEC controls the FMV and thrust lever interlock, based on T/R sleeve pos.
Instruct.: ADIRU = Air data inertial reference unit
CDS = Common display system
DEU = Display electronic unit
FMC = Flight management computer
FDAU = Flight data acquisition unit
TRA = Thrust resolver angle
GENERAL DESCRIPTION (continued)
Inst Note: 2 pages commentaires
pour 1 slide projetée
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FUEL AND CONTROL - GENERAL DESCRIPTION 2/2
• HMU receives commands from the start lever (opens HPSOV)
• HMU receives commands from the EEC and the airplane
• HMU supplies fuel for combustion and servo system operation
• EEC gets and receives data from airplane systems and components
through DEU ’s:
– Engine and fuel indication - Start lever IDLE or CUTOFF command
– Air data (ADIRU) 1 and 2 - Flight management (FMC)
– Control Display Unit (CDU ’s) - Flight data acquisition (FDAU)
• EEC sends signals to engine control lights and switches on the
overhead panel through DEU ’s for some fault detected by the EEC
73-00-00 GENERAL DESCRIPTION (continued)
Instruct.: ADIRU = Air data inertial reference unit
CDS = Common display system
DEU = Display electronic unit
FMC = Flight management computer
FDAU = Flight data acquisition unit
TRA = Thrust resolver angle
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FUEL AND CONTROL - GENERAL DESCRIPTION
• EEC sends input data from some engine sensors to the DEU’s
– This becomes the engine parameters shown on primary or secondary engine
display unit
• EEC gets and receives data from airplane system
– Engine and fuel indication
– Start lever => IDLE or CUTOFF commands HPSOV and gives an ignition signal
– Air data from ADIRU for engine thrust control (TAT, TAP)
– From FMC (target thrust) and CDU (shows EEC maintenance data and
commands BITE test to EEC)
– FDAU sends eng. Data to FDR = data recorder
• EEC sends signal to engine control light and EEC switches on the
overhead panel through DEU’s for some fault detected by the EEC
73-00-00
EEC FAULT ACCOMODATION IF NEEDED
OR GO TO FUEL DISTRIBUTION
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EEC fault acomodation logic
For Instructor info. if needed!
• GOAL: keep complete functional operation of the engine with any
single failure of an electrical/electronic component within the control
system.
– Each channel performs fault identification and accomodation to allow the
EEC system to maintain engine control and communication with airplane
systems.
– No loss of engine operational capability should occurs for a loss of a single
sensor (malfunction or interruption).
– If 2 or more failures cause a loss of capability to perform a system function
(ex.: VSV control), the EEC assumes a default or calculated condition to
achieve the highest level of control thrust within certified limits.
73-00-00 FUEL DISTRIBUTION
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FUEL DISTRIBUTION / Intro
• Fuel distribution system supplies fuel to the engine for combustion and
servo system operation.
• Fuel distribution functions are:
– Pressurization
– Filtration
– Fuel injection
– Heat exchange
73-00-00 DISTRIBUTION - GENERAL DESCRIPTION
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NOTE: distribution is first system of the engine fuel and control
73-11-00
COMPONENT LOCATION
DISTRIBUTION - GENERAL DESCRIPTION
• Fuel circuit:
– from fuel tanks to the low pressure stage fuel pump
– from fuel pump to IDG oil cooler then to the fuel/oil heat exchanger
– from fuel/oil heat exchanger to fuel filter and high pressure stage fuel pump
– Part of the high pressure fuel goes from fuel pump to servo fuel heater and
then to the servo mechanisms of the HMU
– Other part of the high pressure fuel goes to the metering circuit of the HMU
– Then it goes to the fuel flow transmitter, to the fuel nozzle filter
– Fuel goes to the unstaged and staged fuel nozzle circuits SAC through the
BSV
for DAC: BSV (Burner Selection Valve, ex BMV) divides fuel for pilot manifold,
main 1 and main 2 manifolds
• pilot manifold supplies fuel to cooling nozzles and bleed nozzles
• main 1 manifold supplies fuel to cooling nozzles
• main 2 manifold supplies fuel to bleed nozzles
Issue: 4/9/2011
73-11-00 FUEL PUMP ASSEMBLY 53
DISTRIBUTION - COMPONENT LOCATION
• Inline fuel filter, or fuel nozzle filter aft of fuel flow transmitter
• Fuel pump assembly aft of accessory gearbox
• Servo Fuel Heater above the Fuel pump
• IDG oil cooler below HMU
• BSV at 6 O’clock on combustion chamber case
• Unstaged and staged fuel nozzles around combustion chamber case
For DAC,
• 3 fuel manifolds and 20 double tip fuel nozzles around the combustion
chamber case
Issue: 4/9/2011
73-11-00 54
FUEL PUMP ASSEMBLY
• Fuel pump, HMU, and fuel/oil heat exchanger and servo fuel heater can
be removed as an assembly (fuel package)
• Fuel pump fixed on rear face AGB with QAD ring (Quick Attach Detach)
• Fuel pump pressurizes fuel (LP and HP pump) at 1150 - 1204 psi
– to HMU for fuel nozzles and servo mechanisms circuits
• Fuel pump cleans fuel :
– Fuel filter assembly (filter 28μm)
– Instr. Note:
• properly discard disposable fuel filter after removal and inspection
• Bypass SW energizes FILTER BYPASS light in the cockpit, 90 s after landing or
after start (10s then steady):
• FILTER BYPASS Alarm if 10 psid (if disagree > 1 min or disagree > 30 s)
• FILTER BYPASS Open if 15 psid
– PRV bypasses HP gears for 1130 psi diff
– Servo wash filter protects servo mechanism circuit
• Bypass 10 psid
IDG FUEL/OIL COOLER
Fuel filter Delta P switch SB 73014
JFM
Attention à l’intallation du filtre
JFM
Issue: 4/9/2011
55
Servo fuel heater
Issue: 4/9/2011
56
SERVO FUEL HEATER
• Servo fuel heater (SFH) consists of a housing with a heat exchanger
core inside and a cover.
– Core is removable and consists of a number of aluminium alloy U-shap tubes
• Scavenge oil circuit in the SFH increases the temperature of the fuel to
eliminate ice in the fuel before entering the servos systems inside the
HMU
• SFH is mounted on the aft side of the Main oil/fuel heat exchanger
73-11-00 HYDRO MECHANICAL UNIT
Fuite au couvercle du SFH par temp < -15°C / Heat the cover
JFM
Issue: 4/9/2011
73-11-00 57
IDG FUEL/OIL COOLER
• IDG Fuel/Oil cooler is located at 7 O’clock on the fan case,
• IDG Fuel/Oil cooler is a heat exchanger which cools IDG oil by heating
engine fuel that comes from the oil tanks through LP fuel pump.
• Fuel In and Fuel Out on the Forward face
Inst Note : INTERNAL BYPASS (20 - 26 psid)
• IDG Oil In and Oil Out in the left hand side of the IDG Fuel/Oil cooler
IDG FUEL/OIL COOLER DESCRIPTION
Issue: 4/9/2011
24-10-00 58
Instructor note: THIS IS A TENTACLE !
DON’T GIVE TOO MUCH INFO !
IDG FUEL/OIL COOLER - DESCRIPTION
• IDG on the fwd face of the AGB, supplies 115 vac, 400 Hz at a
constant speed to a/c systems
– Inst note: BOEING responsibility
• Constant speed = 24.000 rpm
– maintained between Min Idle and redline (105 %)
• 115 V / 400 Hz up to 90 KVA
• 2 cooling systems
– Oil is first cooled by air/oil cooler (described next page)
• THERMAL DISCONNECT if Oil temp > 361 °F / 200 °C
• INTERNAL BYPASS in case of clogging
– Oil is then cooled by the IDG Fuel/Oil cooler (seen before)
• INTERNAL BYPASS in case of clogging
SERVO FUEL HEATER
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59
IDG air / oil cooler
Issue: 4/9/2011
73-30-00 60
FUEL FLOW TRANSMITTER
• Located at 10 O’clock on the fan frame
• Measures fuel quantity that goes to fuel nozzles
– Inst. Note: Bypass 6 bar
• Data sent through EEC to CDS/DEU which computes fuel flow
– DEU reads start and stop signals from the FF transmiter
– DEU measures time difference and computes to change in fuel weight
Instr. Note:
– Single fuel flow transmitter split to Ch A and B
– If transmitter data are lost or incorrect fuel used value, stays at the last correct
value
– If signal is invalid and FMV position is valid / WF is based on FMV selected
– The EEC averages the last 8 measurements from the WFM to obtain the WF
value and Accuracy is ~1% between 2 and 12.000 lb/h
FUEL NOZZLE FILTER
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73-11-00 61
FUEL NOZZLE FILTER
• Fuel nozzle filter in case of contamination from fuel pump located at 10
O’clock
– Different name:
• In line fuel filter
• Last chance fuel filter
• Fuel nozzle filter
Instructor note
– 300 μm
– By-pass : 84 PSID
– No clogging indicator
– should be replaced when Main fuel filter replaced for clogging
BURNER STAGGING VALVE
SAC
Fuel Nozzle Filter = 300 μm
Fuel Nozzle strainer = 400 μm
Parker only
DAC
Fuel Nozzle Filter = 70 μm
Fuel Nozzle strainer = 84 μm
Parker only
Issue: 4/9/2011
62
BURNER STAGGING VALVE
• BSV at 5:30 (6:00 for DAC) on the HPC case
• BSV controls fuel supply for stagged fuel nozzles (SAC)
For DAC:
• BSV divides fuels into 3 fuel manifolds lines of 2 halves each
– Pilot, Main 1 and Main 2.
• BSV sends position feedback to EEC (channel A & B)
73-11-00 BSV - FUNCTIONAL DESCRIPTION
Soft 7B40
BSV elimination
SB 73-044 / Removal of BSV
+ SB 72-239 new id plug to deactivate BSV system
Issue: 4/9/2011
63
BSV - FUNCTIONAL DESCRIPTION
• EEC controls BSV position through HMU Solenoid
– EHSV supply pressure servo fuel to close the BSV valve
– In case of loss of electrical power, Open position is failsafe
• BSV positions : Open or Closed
–When open, 20 fuel nozzles are fuel supplied (BSV inhibited)
• At high Fuel Air Ratio (FAR)
• Low core speed N2K25<7950 rpm ~55% N2
• High engine temperature indicated by N2K25>11560 rpm ~77% N2
• TRA<maxi climb condition
• Override function
Instr note: better thermal distribution in the combustor
– when closed, 10 fuel nozzles always fuel supplied (BSV energized)
• At low FAR: Reinforced spray pattern (Instr note: increase flame out margin)
73-11-00 FUEL MANIFOLDS
Pour DAC, voir la page de commentaires
Staged / unstaged
Issue: 4/9/2011
73-11-00 64
FUEL MANIFOLDS
• For SAC: 2 fuel manifolds supply fuel to fuel nozzles
– 1 for unstaged fuel nozzles
– 1 for staged fuel nozzles
• Fuel nozzles deliver a spray of fuel in the combustor.
• Distribution is alternatively an unstaged then a staged
For DAC option:
• Staged fuel manifolds of 2 halves each supply fuel to fuel nozzles tips:
– Pilot
– Main 1
– Main 2
FUEL NOZZLES
Issue: 4/9/2011
65
FUEL NOZZLES
For SAC:
• 20 Fuel nozzles / Parker only
– 4 Natural (silver) band nozzles, next to igniters only.
Instr. Note: supply fuel with a larger spray pattern
– 16 Blue band nozzles, all other locations.
• All FN have primary fuel flow (from 15 PSIG) and secondary (from 125
PSIG) and inlet strainer 400 μm
• Fuel nozzle shrouds collect fuel leak (no drain for the fuel nozzle shrouds)
For DAC option:
• 20 double tip fuel nozzles:
– 10 cooling fuel nozzles identified by a blue band (with Pilot and Main 1 tips)
– 10 Bleed fuel nozzles identified by a gold band (with Pilote and Main 2 tips)
• All FN have primary fuel flow and secondary
• Fuel nozzle shrouds collect fuel leak (no drain for the fuel nozzle shrouds)
73-11-00 FUEL DISTRIBUTION - FONCTIONAL DESCRIPTION
Issue: 4/9/2011
66
HMU
• HMU fixed on the MFP, part of the fuel package rear side of the AGB
• Supplies fuel for servo system operation and combustion
• Receives electrical signals from EEC
– Internal servo valves convert into fuel pressure/flow
• Electrical connections:
• EEC channels A & B
• HPSOV solenoid
– Energized by start lever and fire switch
• Switch connector (HPSOV, airframe shutoff indicator)
• Fuel connections:
• Metered fuel (on top)
• Connections to engine valves/actuators
• Drain
• Raised letter for identification of fuel connection
73-21-00 FUEL FLOW TRANSMITTER
Issue: 4/9/2011
67
ENGINE FUEL CONTROL - FONCTIONAL DESCRIPTION
Instr Note:
• Describe the fuel distribution Fuel nozzle
• Introduce the fuel distribution Servos system
• High pressure and shutoff valve (HPSOV) stops the metered fuel flow
when closed
– HPSOV commanded open/closed by start lever
closed by fire switch and start lever
– EEC override the start lever to close the FMV (hot start protection)
• EEC controls servo fuel distribution to manage servo systems
• BSV solenoid controls the BSV valve (SAC)
For DAC:
– BSV solenoid controls the MSV in the BSV for Main 2 FN tips fuel supply
– EHSV in the BSV controls DMV for Main 1 FN tips
73-11-00 ILCBT
Issue: 4/9/2011
68
ILCBT
Instructor NOTE: lancer la CBT sur les postes élèves
• Fuel goes to fuel pump LP stage to IDG oil cooler
• From IDG oil cooler, goes to fuel/oil heat exchanger
• Then to fuel filter (bypass valve for clogging)
• Back in fuel pump, HP stage (high pressure relief valve)
• Servo wash filter cleans fuel for HMU servo system distribution
• HMU servo system operates Air valves
• HPSOV opens using fuel pressure when start levers opens FMV
• HPSOV closes (solenoid energized) when close signal from start levers,
fire switches or EEC (close FMV during starting)
• BSV solenoid valve closes BSV
73-11-00 FUEL CONTROL - INTRODUCTION
Issue: 4/9/2011
73-21-00 69
FUEL CONTROL - INTRODUCTION
73-21-00
• Fuel control system controls fuel flow for engine operation
• 2 Fuel control subsystems:
– Metered fuel control
– Servo fuel control
ENGINE CONTROL - GENERAL DESCRIPTION
Issue: 4/9/2011
73-21-00 70
ENGINE CONTROL - GENERAL DESCRIPTION
• EEC is primary engine control for fuel and control system
(brain of the engine)
• The CDS/DEU transfer signals and data to and from EEC and airplane
• EEC sends thrust rating and TLA data to auto-throttle computer
– Auto-throttle computer operates the thrust lever
• Controls and indications are in flight compartment
• Some controls in flight compartment supply control data directly to
some engine components.
Inst. Note: Data transfer between DEU, AT computer, and EEC through
ARINC 429 data bus (ARINC 429 = Air Radio Inc 429)
CDS for Nice to Know or go direct to
ENGINE CONTROL - INTERFACES
Issue: 4/9/2011
71
Engine sensor interfaces
Issue: 4/9/2011
73-21-00 72
ENGINE CONTROL - INTERFACES
• EEC is 2 chan. computer A & B, independent but communicate by a
CCDL during operation (CCDL = Cross Channel Data Link)
– Through automatic selection there is one Active and one standby channel
– Active channel controls engine operation
• EEC receives command signals from the flight compartment:
– Start lever / start switch / ignition selection switch / TLA resolver
• EEC interfaces with A/C systems:
– A/C and engine data through CDS/DEU
CDS/DEU = Common Display System/ Display Electronic Unit
– Flight data through FMC = Flight Management Computer
– TLA angle position through Auto throttle computer
– Air data through ADIRU = Air Data and Inertial Reference Unit
– Thrust Reverser lever interlock solenoids position
• EEC interfaces with Engine systems:
– ID plug - HMU = Hydro Mechanical Unit - Engine indication data
(sensor & position feedback signals from valves / actuators)
COMP. LOCATION - RIGHT SIDE
Input / Output
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73-21-00 73
FUEL CONTROL - COMP. LOCATION - RIGHT SIDE
• Locate:
– EEC on right side of fan case
• Identification plug at bottom of EEC
– EGT wiring harnesses on LPT case
– N1 speed sensor on the fan case rear the oil tank
– T12 sensor on right side of inlet cowl
– HPTACC sensor on right side of hpt case
– A/T clutch pack below flight compartment control stand
NOTE: control stand described in details next page !
ENGINE CONTROLS - CONTROL STAND
Issue: 4/9/2011
74
Thrust Limiting logic or go direct to :
FUEL CONTROL 76-00-00 - COMP. LOCATION LEFT SIDE
FUEL CONTROL - CONTROL STAND
• The engine control system supplies manual and auto control inputs to
operate each engine:
– 2 Start levers operate switches that interface with other systems for starting
– 2 FWD Thrust levers supply MANUAL thrust commands signal to EEC’s
through resolvers
• Thrust levers connect mechanically to resolvers.
– TRA>34° = fwd thrust TRA<34° = reverse
• An interlock latch prevents the operation of REV TLA during fwd thrust
– 2 Reverse Thrust interlock solenoids limit lever position as function of sleeve
position
Inst note: Reverse thrust lever have 5 positions:
- stow - interlock stop - Detent 1 - Detent 2 -Maxi reverse
Thrust lever interlock can be tested with CDU (chap 77)
Issue: 4/9/2011
75
Control stand
Issue: 4/9/2011
76
Control stand
Issue: 4/9/2011
77
Start levers
Issue: 4/9/2011
78
Start levers internal switches
Issue: 4/9/2011
79
ENGINE CONTROL - COMP. LOCATION - LEFT SIDE
• Locate
• EEC alternator on front of AGB
• HMU, attached to fuel pump
• PT25 sensor at 5:00 position - behind fan duct panel
(PT25 = HPC inlet temperature data, P optional)
• T3 sensor 12:00 on the combustion chamber
• N2 speed sensor on front of AGB
73-21-00 ELECTRONIC ENGINE CONTROL
Issue: 4/9/2011
80
ELECTRONIC ENGINE CONTROL
• EEC receives information to calculate command logic signals
and sends control signals to operate the engine
– has many electrical and pneumatic connections
– Supplies data to CDS/DEU and to CDU (Control Display Unit)
– A Ram air for EEC cooling (Inst. Note: EEC over temp. 105°C)
• EEC is 2 chan. computer A & B, independent but communicate by a CCDL
during operation (CCDL = Cross Channel Data Link)
• Electrical connections - J1 to J10 harnesses
– J1 J3 J5 J7 J9 (Inst. Note: odd = impair) = chan. A
– J2 J4 J6 J8 10 (Inst. Note: even = pair) = chan. B
• Id plug at P11 port
– P11, J1 and J2 used to update software with PDL (option) = Portable data load
– You use CDU maintenance pages to check software configuration and Eng.
N°
• Air connections - PS3 - P0 + optionals (PS13 & P25).
Inst. Note: for info, weep hole on the pneumatic lines
73-21-00 IDENTIFICATION PLUG
Parameters
W or W/O models
Attention, pas finie
Soft 7B40
elimination BSV
Parameter
limits
Issue: 4/9/2011
81
IDENTIFICATION PLUG
• Attached to fan case by a cable and is connected to EEC (P11).
• ID plug supplies configuration data codes to the EEC:
– Engine family and model + Bump (optional)
– Maximum engine thrust rating
– N1 trim modifier (Fan-speed modifier) from 0 to 7 trim level
• Increase EGT margin for a nominal thrust setting at take off
• EEC computes the appropriate N1K25 to reduce excessive thrust margin
• Computed N1 trim is inhibited from certain flight levels:
– Alt. >= 15.500 ft or M. >= 0.4 or N1 near 0.46% from RED LINE
– Combustor configuration (SAC or DAC)
– Engine condition monitoring (optional): PMUX or NON PMUX
Instr. Note:
• most of these data will show on the CDU’s
• engine serial number data is entered through the CDU and is contained in the
NVM of the EEC
• The ID plug remains with the engine when the EEC is removed/replaced
73-21-00 EEC ALTERNATOR
Fuse connections: Rating, Plug type (5C,7B)
Push pull connections: SAC, DAC, Trim, PMUX
N1 trim
Issue: 4/9/2011
82
EEC ALTERNATOR
• Primary power source for EEC
inst. Info.: 100% N2 speed = 18697 rpm
• Locate - describe
• Supply power for channel A & B from the EEC
• Lock AGB to remove/tighten rotor retaining nut
inst. Info.: use guide pins to remove stator to avoid magnetic contact in
between the stator and the rotor and avoid damage to component
73-21-00 EEC ELECTRICAL POWER SUPPLY
Issue: 4/9/2011
83
EEC ELECTRICAL POWER SUPPLY - SLIDE 1/4
• CDS/DEU send start and switch position demand to EEC
• The EEC alternator is primary power supply for EEC
– EEC alternator speed logic monitors EEC alternator speed
– EEC alternator operates When 12%<N2 speed> 15%
• A/C transfer bus is another source when N2 speed <15% or in case of
EEC alternator failure
• Alternate power relay supplies a/c transfer bus to EEC Ch A and B
– Alternate power relay is in the Aiplane electrical junction box
Instr. Note:
– One EEC channel can be powered by alternator, one by transfer bus
– Fault message shows on CDU if alternator cannot power EEC
73-21-00 EEC ELECTRICAL POWER SUPPLY - SLIDE 2
12% 15%
N2 SPEED
Engine Alternator power
A/C power Back-up A/C power
POWER SOURCE
Issue: 4/9/2011
84
EEC ELECTRICAL POWER SUPPLY - SLIDE 2/4
• Engine START LEVER energizes solenoid in the Alternate power relay to
the ON position
– Start lever to idle
– Start switch to ground or continuous
• Then, Alternate power relay energizes and transfer bus supplies power to
EEC
73-21-00 EEC ELECTRICAL POWER SUPPLY - SLIDE 3
Issue: 4/9/2011
85
EEC ELECTRICAL POWER SUPPLY - SLIDE 3/4
Transfer relays inside EEC energize when EEC alternator reaches set N2
speed (12 to 15 %)
• When energized, EEC alternator power supply connects to EEC
The EEC now operates by power from the Alternator
73-21-00 EEC ELECTRICAL POWER SUPPLY- SLIDE 4
Issue: 4/9/2011
86
EEC ELECTRICAL POWER SUPPLY - SLIDE 4/4
When loss of EEC alternator speed value:
• Alternator speed logic de-energizes Transfer relays in the EEC for the
identified faulty Channel or both
• Then, Alternate power relay supplies A/C transfer bus power to EEC Ch
A or/and B
Now, the EEC operates by power from A/C Transfer bus
Instr. Note:
– One EEC channel can be powered by alternator, one by transfer bus
– A fault message shows on CDU if alternator cannot power EEC
77-11-00 N1 SPEED SENSOR
Issue: 4/9/2011
87
N1 SPEED SENSOR
• N1 speed sensor is right hand side of the engine aft. the oil tank
• N1 sensor consists of three independant sensing elements
– Each sensing element is composed of an electrical winding around a magnet
• Dampers on the probe prevent unwanted external vibration
• Supply N1 speed signal to EEC & CDS/DEU
and Airborne Vibration Monitoring (AVM) signal conditioner
Make sure the gap between the flange and housing is in limits when you
install N1 sensor
Caution: you can damage the sensor if you tighten bolts with gap out of
limits
77-11-00 N1 SPEED SENSOR schematic
Issue: 4/9/2011
88
N1 SPEED SENSOR - schematic
• A ringed gear (or Phonic wheel) with 30 teeth passes the sensing
elements of speed sensor and induces an analog signal sent to the EEC
=>CDS/DEU=>AVM system
• EEC converts the analog signal to a digital signal for internal processing
and output to DEU for Display on the Common Display System (CDS)
• A thicker tooth on the ringed gear provides phase angle for the Airborne
Vibration Monitoring (AVM)
77-11-00 N2 SPEED SENSOR
Issue: 4/9/2011
89
N1 SPEED INDICATION
• DEU uses input from EEC N1 speed sensor directly
– N1 indication shown on CDU
• White digital readout and box shows N1 LP rotor speed -*
• White pointer shows N1 speed indication -*
– A gray shaded area follows the pointer -*
• A green reference bug shows the N1 target set by crew or FMC
– A white colored digital display shows manually set N1 only
• White N1 command sector shows difference between N1 command and act. N1
– N1 command set by TL position
• N1 redline set by EEC
– *RED Color set when speed > limit
• If there was exceedance during engine operation
– Digital readout and surrounding box will change to red upon engine shutdown
• N1 exceedances or sensor failures can be displayed by CDU
77-11-00 N2 INDICATION
Issue: 4/9/2011
90
N2 SPEED SENSOR
Inst. Note: Sensor is new to 737
• The N2 sensor consists of 3 independent sensing elements and 3
connectors
– Each sensing element is composed of an electrical winding around a
magnet
• N2 sensor on front face of the AGB
• There is no gap to measure for this sensor
77-11-00 N2 SPEED SENSOR - schematic
Issue: 4/9/2011
91
• A ringed gear (or Phonic wheel) with 70 teeth passes the sensing
elements of speed sensor and induces an analog signal sent to the
EEC =>CDS/DEU=>AVM system
• EEC converts the analog signal to a digital signal for internal
processing and output to DEU for Display on the Common Display
System (CDS)
• A thicker tooth on the ringed gear provides phase angle for the
Airborne Vibration Monitoring (AVM)
N2 SPEED SENSOR - schematic
77-11-00 T12 SENSOR
Issue: 4/9/2011
92
N2 INDICATION
• DEU uses input from EEC N2 speed sensor directly
– N2 indication shown on CDU
• White digital readout and box shows N2 HP rotor speed -*
• White pointer shows N2 speed indication -*
– A gray shaded area follows the pointer -*
• N2 redline set by EEC
– *RED Color set when speed > limit
• If there was exceedance during engine operation
– Digital readout and surrounding box will change to red upon engine
shutdown
• N2 exceedances or sensor failures can be displayed by CDU
77-11-00 EGT INDICATION
Issue: 4/9/2011
93
EGT THERMOCOUPLES AND HARNESSES
• 8 T/C inside second stage LPT nozzles
– provides an analog signal proportional to exhaust HPT rotor temperature to
EEC
• Wires contained within tubes go from the T/C to Junction box
• 4 EGT harnesses connect from junction box to EEC
Inst Note: YOU REPLACE THE ENTIRE HARNESS ASSEMBLY,
T/Cs ALONE ARE NOT LRUs
• EGT T/C and harnesses, monitor T49.5 gaz temperature rearward the
HPT rotor for engine control and indicating
• EEC sends EGT data to CDS/DEU.
– The temperature shown is an average of the 8 T/C
77-21-00 P0 SENSOR
Issue: 4/9/2011
94
EGT INDICATION
• White digital readout and box shows EGT in °C on CDU -*
• White pointer shows EGT position -*
– A gray shaded area follows the pointer -*
• * Color turns amber when EGT > to max cont. 925+3° C (not during T/O)
– EGT max continuous = EGT caution range displayed as an amber band (arc)
• * Color turns red when EGT > redline (950+10° C) or start redline (725° C)
• If EGT was > to redline, the box will change to red upon engine shutdown
• When N2 speed drops below 10%, EEC deenergizes and EGT digital readout goes
blank
• During possible hot start, EGT digital readout will flash. Never in flight
• EEC stops fuel flow (FMV) and ignition when EGT > to start redline
Inst. Notes: Through CDU you can find out / Peak of exceedance / Duration /
Flight Nb / Date and GMT / Altitude / Airspeed
77-21-00 ENGINE FAIL MESSAGE
Issue: 4/9/2011
95
ENGINE FAIL MESSAGE
• « ENG FAIL » message supplies an early warning of an engine
malfunction
• Amber colored message shows on EGT display when:
– Engine speed =/> idle
– Both start levers are at idle position and the N2 decreases below a
sustainable idle condition
Inst. Note: min. core speed < 7230 rpm
• It remains illuminated until either:
– Engine recovers
– Or start lever moved in Cut off (engine shut down)
77-21-00 AVM SYSTEM
Issue: 4/9/2011
96
HPTACC SENSOR
• HPTCC sensor at 3 O’clock on the HPT case, aft. fuel nozzles
• Supplies HPT shroud temp to EEC for HPTCC control logic
Instr notes:
– Single sensor for both Channel A & B
– HPTCC = HPT clearance control to maintain an acceptable clearance in
between the HPT shrouds and the HPT blades
• Thermocouple (idem T3) - dissimilar metal sensor; produces a milli amp
current proportional to temperature.
–When temp incr. mA incr.
–When temp decr. mA decr
• A shim controls the position of sensor in the HPT case
– A clearance must be check during sensor replacement on wing
73-21-00 EGT THERMOCOUPLES - HARNESSES
Issue: 4/9/2011
97
T12 SENSOR
• Supplies fan inlet temp to EEC for thrust management calculation
• EEC supplies constant voltage to platinum sensor
– Resistance changes with temp
– EEC converts delta Voltage into LPC inlet temp
• Access door right hand side of the inlet cowl
Instr. Note:
– TAKE CARE, risk of screw loss in the inlet cowl during removal (modif
BOEING)
– no more Ps12 on -7
73-21-00 PT25 SENSOR
Issue: 4/9/2011
98
T3 SENSOR
• T3 at 12 O’clock on the Comb. Case
• Supplies CDP temp to EEC for fuel air ratio control logics of
– BSV
– HPTACC
• Thermocouple - dissimilar metal sensor (chromel-alumel); produces a
milli amp current proportional to temperature.
–When temp incr. mA incr.
–When temp decr. mA decr.
Instr note: PS3 not shown
• PS3 static air pressure is located at 9 O’clock on the Comb. Case
• Supply CDP air pressure to EEC for fuel metering logic
73-21-00 HPTACC SENSOR
Issue: 4/9/2011
99
PT25 SENSOR
• PT25 sensor at 7 O’clock to the inner wall of the fan frame
• Supplies HPC inlet temp/pressure to EEC for engine fuel metering
valve control logic
– VSV, VBV, TBV, HPTACC
• EEC supplies constant voltage to platinum sensor (idem T12)
– Resistance changes with temp
– EEC converts delta Voltage into HPC inlet temp
• Optional tube sends air pressure P25 to EEC for engine condition
monitoring (modular analysis)
– EEC converts pressure signal into electrical signal
73-21-00 T3 SENSOR
Issue: 4/9/2011
10
0
P0 SENSOR
• P0 sensor consists of a vent plug attached to a pressure plate on the
bottom panel of the EEC
• P0 used by EEC as an input of ambient static air pressure
• Ambient pressure is converted to an electrical signal by transducers
– 1 for Ch A
– 1 for Ch B
77-21-00 PS3 SENSOR
Issue: 4/9/2011
10
1
PS3 SENSOR
• PS3 sensor consists of static air pressure pickup just aft the fuel
nozzles at 9:00
• Pressure line runs at the bottom of HPC to the tube bundle and is
linked to the bottom plate of the EEC
• PS3 sensor provides HPC discharge air pressure to the EEC for use in
fuel metering
• Static pressure is converted to an electrical signal by 2 transducers,
– 1 for Ch. A
– 1 for Ch. B
Inst. Note: Weep hole on the PS3 to drain moisture or water
77-21-00 EEC
Issue: 4/9/2011
10
2
73-21-00
ELECTRONIC ENGINE CONTROL 1/3
• EEC is a dual channel A & B computer
– 2 independent channels, but connected by a CCDL during engine operation
– EEC chooses either ch A or B as the active control channel
– Active channel changes at each engine start
• If the active channel becomes defective, the standby channel becomes active
• EEC Usual power supply is EEC alternator from 12% N2
– up to 15% N2, the A/C transfer busses supply electrical power or is selected
as an alternate when EEC alternator is deffective
– A/C transfer busses supply electrical power for ignition control (left system)
– A/C standby busses supply electrical power for EEC & ignition control (right
system)
• TLR (Thrust Lever Resolver) sends TRA (Thrust Resolver Angle) to EEC
– EEC uses TRA to control FMV for thrust command and Reverse thrust
• Auto throttle computer receives engine data from EEC
• N1 speed - Maxi N1 speed - Engine thrust rating
FOLLOWING NEXT SLIDE
Inst Note: 3 pages commentaires pour 1 slide projetée
Issue: 4/9/2011
10
3
73-21-00 FOLLOWING NEXT SLIDE
ELECTRONIC ENGINE CONTROL (continued) 2/3
• Servo system temperature, pressure & position sensors supply
component position data to EEC for operation
• Dual sensors with model: N1, N2, T25, PS3, T3, FMV, VSV, VBV,
• Parameters without model: TC, TEO, TECU, HPTC, PEO, LPTC,
• P0 = EEC Air pressure
• Identification plug supplies EEC with
• Identification plug type
• Engine thrust rating
• N1 trim level
• Engine combustor config (SAC / DAC)
• EEC communicates with aircraft computers
– ADIRU supplies Total air pressure and temperature data to EEC through
CDS/DEU’s
– EEC sends engines data to FMC (Flight Management Computer) and CDU
• CDU operates EEC bite, exceedance data, fault data through CDS/DEU’s
Issue: 4/9/2011
10
4
ELECTRONIC ENGINE CONTROL (continued) 3/3
• Start switch sends ignition commands to EEC directly, and to CDS/DEU’s
• Start lever sends engine start commands to EEC through CDS/DEU’s
– Start levers in idle:
• EEC controls electrical power to ignition
• EEC operates the FMV to open
• command the HPSOV to open, then fuel supplies the combustion
– Start levers in cutoff closes HPSOV and the fuel distribution
• Fire handle switch on P8 aft panel closes also the HPSOV
• EEC adjusts the FMV based upon air and anti-ice bleed demands to set
appropriate engine thrust
– EEC controls servo system: EHSV
– EEC controls the FMV based upon thrust reverser LVDT for sleeve position
73-21-00 HMU
Issue: 4/9/2011
10
5
HMU
INST NOTE: THIS SLIDE HAS ALREADY BE SEEN BEFORE WITH THE
FOLLOWING COMMENT: just repeat it for memory
• HMU receives electrical signals from EEC
– Internal servo valves convert signal into fuel pressure/flow
• Electrical connections:
• EEC channels A & B
• HPSOV solenoid
– Commanded by the start lever and the fire switch
• HPSOV switch connector
73-21-00 HMU - FUNCTIONNAL DESCRIPTION
Issue: 4/9/2011
10
6
HMU - FUNCTIONAL DESCRIPTION
• HMU has 2 fuel systems
– Metered fuel supplies Fuel metering system
• EEC commands the FMV EHSV
– FMV EHSV uses servo fuel pressure to open and operate FMV
• Fuel from FMV goes to HPSOV, then fuel goes to fuel flow transmitter/combustion
• Thrust lever resolver sends TRA to EEC to operate FMV
• EEC uses resolvers feedback for the FMV position monitoring
– Servo fuel pressure supplies EHSV (Electro Hydraulic Servo Valves)
• EHSV’s use servo fuel pressure to operate engine air bleed systems:
– Air valves: VBV, VSV, TBV, HPTCC, LPTCC
• HPSOV solenoid uses servo fuel pressure to close HPSOV
–When Start lever in cutoff position or pulling fire handle switch up
– The EEC does not monitor HPSOV position & solenoid
– HPSOV pos. Switch controls valve position light on p5 panel in the cockpit
• N2 mechanical OSG (Over Speed Governor) uses servo fuel pressure to
open bypass valve (106% N2).
Inst note: tested by EEC during start betw. 3 to 4000 N2 rpm
BSV 73-21-00 - FUNCTIONNAL DESCRIPTION
Switch
Rev “K”
SB 73-037
Issue: 4/9/2011
10
7
73-21-00
THRUST CONTROL
• EEC and HMU schedule fuel flow to give engine power at all Thrust Lever
positions: - Fwd thrust - Reverse thrust - Idle
• At idle (min idle speed = 58.8% N2 and mini Fuel Flow = 300 lb/h 136 kg/h)
• EEC receives ADIRU data (total air pressure: PT & TAT, altitude and mach)
• EEC controls & adjusts power to prevent flame out within N2 speed control and
demands for bleed air systems and accessories
• On Fwd thrust: EEC receives ADIRU data (PT & TAT) and resolver inputs
• If not available (loss ADIRU data), EEC switches to soft alternate mode (calculates
ADIRU data from engine sensor inputs = synthetized mach number)
• when TL is reduced below max. cont. or when you push the EEC switch, Hard
alternate mode is set
• On Reverse thrust mode: selected when T/R reach 70% up to 90% deploy
• EEC receives LVDT position signal and controls the T/R interlock position
• It controls Thrust and T/R condition
• It sends data to CDS/DEU for REVERSER UNLOCKED message and LVDT fault
EEC - FUNCTIONAL DESCRIPTION
Issue: 4/9/2011
10
8
73-30-00
FUEL INDICATING COMPONENTS
• Fuel indicating system supplies data for:
– High pressure shutoff valve (HPSOV) position
– Fuel flow rate
– Fuel used
– Fuel filter bypass
– HPSOV in HMU sends a valve position signal to EEC / CDS/CDU position light
• “ENG VALVE CLOSED” = dim (blue light); VALVE OPEN = light off
• Valve position disagree between actual and commanded = bright (blue light)
– Fuel flow transmitter sends fuel flow signals to EEC
• EEC converts signals to a fuel flow weight and sends it to CDS/DEUS
• DEU calculates fuel rate/used data
– Fuel flow indication control switch, in the cockpit, controls the operation for fuel
flow rate and used displays
• RATE: shows current fuel flow rate in digital and analog format (rate = usual position)
• USED: shows total fuel used since counter last zero out , digital only, for 10 sec
• RESET: sets counter to 0
Instr. Note: Fuel flow, displayed in either lbs or kg per hour, is customer option
FUEL FILTER DIFFERENTIAL PRESSURE SWITCH
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10
9
Fuel Flow Transmitter
Issue: 4/9/2011
11
0
FUEL FILTER DIFFERENTIAL PRESSURE SWITCH
• Fuel filter differential pressure switch is at 8:00 on the fan case
• Fuel filter differential pressure switch sends filter clog data to
CDS/DEUS
– Switch assembly has 2 switches (Channel A and B)
–When differential P in between inlet and outlet >11.5 PSID
• EEC sends discrete signal to CDS/DEU
• DEU switches to ground to illuminate: FUEL FILTER BYPASS= amber light
– On P5 overhead panel in the cockpit
• When FUEL FILTER BYPASS lights comes on
– Interrogate CDU for trouble shooting then FIM = Fault Isolation Manual
73-30-00 HPSOV INDICATION
Issue: 4/9/2011
11
1
HPSOV INDICATION
• HPSOV is Internal component of the HMU
• HPSOV opens and closes to allow metered fuel flow
• Blue « ENGINE VALVE CLOSED » light provides an indication to
HPSOV position
– Dimly illuminated = valve closed
– Light off = valve open
– Bright = desagreement between actual and commanded position
73-30-00 OIL INDICATING
Issue: 4/9/2011
11
2
EEC FUNCTIONAL DESCRIPTION
• EEC Calculate and Control the idle speed:
– Prevents flameout and adjusts N1 speed when HP Compressor supplies bleed
air to air and anti-ice systems.
– In flight, EEC does not let the N2 to go below 58.8%, Fuel flow will not go
below 300 lb/h (136 kg/h)
• EEC receives Pressure, altitude and mach number that have an effect on
idle speed control: PT and TAT come from ADIRU
– EEC goes to soft alternate mode if ADIRU data is incorrect
• Then, It calculates the last available input data to control the engine thrust
– EEC goes to Hard Alternate mode when you push the EEC switch to Off
• This mode is set in automatic when EEC already in the soft alternate mode
and when the pilot moves the TL to idle
• The maxi rated thrust changes to a maxi allowable thrust.
– In this condition the actual N1 can be more than the commanded N1
• CDU’s show faults and maintenance information for the engine
– They control also ground test (BITE) for the engine systems fault isolation
73-21-00 ENGINE CONTROL LIGHT and EEC SWITCH
Issue: 4/9/2011
11
3
Idle control
Issue: 4/9/2011
11
4
73-21-00
EEC CTRL LIGHT & EEC SWITCHES 1/2
• 3 engine indications lights on P5 aft overhead panel
– ENGINE CONTROL - amber light = engine cannot operate correctly
NO DISPATCH
DOES NOT COME IN FLIGHT
– EEC switch ON light
– EEC switch ALTN light
• white ON and amber ALTN light = show different EEC mode operations
• When engine control light comes, you must use the CDU and FIM to find and isolate
the problem (FIM = Fault Isolation Manual)
• EEC switch ON and amber ALTN operations:
– Normal mode: the ON light is on (white)
– Soft alternate mode: ON light and ALTN light are on (amber)
– Hard alternate mode: Switch is off, ALTN light is on, the ON light is off.
EEC CTRL LIGHT & SWITCHES (cont’d)
Inst Note: 2 pages commentaires pour 1 slide projetée
Issue: 4/9/2011
11
5
• EEC goes to Soft alternate mode (or soft reversionary mode) when PT
from both ADIRU are invalid,
– EEC makes a synthetized Mach number from:
– TAT - Standard day temp. - Last valid delta temp. from standard day
– Both EEC’s must be placed in HARD ALTERNATE mode before reduce TLA
• If one EEC is in NORMAL MODE and the other EEC is in SOFT ALTERNATE
mode, it can cause a throttle stagger
• EEC goes to Hard alternate mode (or reversionary mode) when:
– EEC is already in soft alternate mode
– EEC switch is pushed by the crew to the off position
– the crew Moves the thrust lever to idle (reduce TLA down to ~52°C)
• EEC makes a calculate Mach number from:
– Electronic pressure and altitude table
– Calculates standard day delta Temp. = to the rating corner point (30°)
– There is no overspeed protection on this mode
73-21-00
EEC CTRL LIGHT & EEC SWITCHES (cont’d) 2/2
T/R INTERLOCK SOLENOIDS
Soft et hard
prudence
Issue: 4/9/2011
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6
Electrical engine harnesses
• SQUELETTE
Issue: 4/9/2011
11
7
Electrical engine harnesses
• J5 / J6 /J7 GNA GNA GNA !!!!
Issue: 4/9/2011
11
8
ILCBT - EEC CONTROL LIGHT
• PRIMARY PARAMETERS
• CONTROL LIGHT
• SELF COMMENTED LESSONS
•
73-21-00 GO TO SHOP
Issue: 4/9/2011
11
9
• Follow fuel circuit !
• Show fuel pump assembly - LP pump - fuel filter
• Show IDG oil cooler - IDG air cooler - IDG
• Show main heat exchanger (chapt 79)
• Show fuel circuit through HP pump and HMU (fuel control)
• Show fuel flow transmitter
• Show inline fuel filter
• Show BSV
• Show staged/unstaged circuit
• Show fuel manifolds - fuel nozzles (blue/natural-silver band)
• Describe fuel nozzle shroud - no drain
OBJECTIVES: DESCRIBE/LOCATE FUEL DISTRIBUTION SYSTEM
COMPONENTS ONTO THE ENGINE
73-11-00
GO TO SHOP - FUEL SYSTEM 1/2
GO TO SHOP - continued
Issue: 4/9/2011
12
0
OBJECTIVES: DESCRIBE/LOCATE ENGINE CONTROL/INDICATING
SYSTEMS COMPONENTS ONTO THE ENGINE
GO TO SHOP - FUEL SYSTEM 2/2
• SHOW EEC - CONNECTORS - ID PLUG
• SHOW EEC ALTERNATOR - MANUAL DRIVE PAD ON AGB
• SHOW LVDT ON T/R
• SHOW HMU - CONNECTORS - FUEL LINES
• EXPLAIN REMOVAL AS FUEL PUMP PACKAGE OR HMU - HIDDEN
BOLTS
• SHOW:
- T12 (inlet cowl) - PT25 (7:00, inner wall of the fan frame)
- T3 (12:00 HPT CASE) - PS3 (9:00 COMB)
- HPTACC SENSOR (3:00 on the HPT case)
• SHOW FUEL FLOW TRANSMITTER - FUEL FILTER dP SWITCH
73-21-00 ENGINE AIR
Issue: 4/9/2011
12
1
CFM56-7 LINE & BASE COURSE OUTLINES
1. Maintenance Documents
2. Power Plant General (71)
3. Engine Exhaust (78)
4. Engine General (72)
5. Fuel and Control System (73) (SAC)
5. Fuel and Control System (DAC)
5. Engine Electrical Wiring Harnesses
6. Air System (75)
7. Ignition System (74)
8. Start System (80)
9. Oil System (79)
10. Engine Indicating System (77)
11. Engine Fault Isolation - CDU Messages
75-00-00 AIR SYSTEM - INTRODUCTION
Issue: 4/9/2011
12
2
75-00-00
ENGINE AIR - INTRODUCTION
• Control the air in the engine for these functions
– control of primary airflow through the compressors
• VSV: Variable Stator Valve
• VBV: Variable Bleed Valve
• TBV: Transient Bleed Valve
– control of air bleed for turbine clearance control
• HPTCC: High Pressure Turbine Clearance Control
• LPTCC: Low Pressure Turbine Clearance Control
AIR SYSTEM
Issue: 4/9/2011
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3
Engine air / General description
Issue: 4/9/2011
12
4
AIR SYSTEM
• EEC is primary control of engine air system
• EEC sends commands to HMU to operate components as necessary
– VBV actuator: controls Low P comp. Air discharge
– VSV actuator: controls High P comp. Airflow section
– TBV actuator: controls High P comp. 9th stage Air discharge
– HPTACC actuator: controls High P comp. 4th and 9th stage Air discharge
to HP turbine Shroud support for HPT blade clearance control
– LPTACC actuator: controls Fan Air discharge to LP turbine Case for LPT
blade clearance control
• EEC monitors position of components for loop control (feedback)
75-00-00 VSV SYSTEM
Issue: 4/9/2011
12
5
75-21-00
HPTCC - COMPONENT LOCATION
• HPTACC system consists of:
• HPTACC valve
• 9th stage bleed air duct
• HPTACC manifold
• HPTACC valve at 3:00 position
• 9th stage bleed air supply is at 2:00 position
– Connects to HPTACC valve
• HPTACC manifold on the HPT case
• HPTACC system controls bleed air from 9th and 4th stg HPC to minimize
the HPT blade tip clearance for all engine operating condition
– Improve specific fuel consumption
HPTACC - FUNCTIONAL DESCRIPTION
Issue: 4/9/2011
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6
75-21-00
HPTACC - FUNCTIONAL DESCRIPTION
• EEC monitors parameters from the CDS/DEU = P0 and TAT
• EEC also monitors these engine parameters
– N2 speed, T25 (HPC inlet temp), T3 (HPC discharge temp), HPTACC sensor
temp.
• EEC measures position of 4th and 9th bleed air control valve actuator
– Both 4th and 9th stage bleed valves operate from the same actuator
• EEC sends commands to HMU EHSV to supply servo fuel pressure to
operate the valves
• EEC monitors through LVDT the new position of valve actuator
–When positions agree with EEC required position, EEC sends signal to HMU
– HMU will null servo fuel pressure to keep valves in new position
Inst. Note: Failsafe position = valve closed
HPTACC - GENERAL DESCRIPTION
Issue: 4/9/2011
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7
75-21-00
HPTACC - GENERAL DESCRIPTION
• The valves Regulate thermal expansion of HPT shroud support
– To optimize the clearance between HPT blade Tip and shrouds
• tight during steady state condition
• open enough during transient (When temp not stable or high power) to avoid contact
rubs of HPT blade tip with shrouds
• Valves operate with 5 modes or sequences:
– No air = when engine is off and fail-safe for loss EEC or HMU
– High flow 9th stage = actuator set to 22% extension, 4th stge valve closed
– Low flow 9th stage = actuator set to 42% extension, 4th stge valve closed
– Mixed = actuator set in between 43% to 99% extension
– Full 4th stage = actuator set to full extension, 9th stge valve closed
• HPTACC valve consists of :
– 9th stage air valve body - 2 LVDT connectors
– 4th stage air valve body - One fuel manifoild mount flange
– 1 actuator for each valve - One 4th stage air inlet duct
LPTACC - COMPONENT LOCATION
Issue: 4/9/2011
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8
HPTCC
Issue: 4/9/2011
12
9
75-22-00
LPTACC - COMPONENT LOCATION
• LPTACC system consists of the following:
– Valve
– Air supply duct
– manifolds around LPT case
• LPTACC valve, 4:00 position on the HPC case
– Mounts aft of rear fan frame
• LPTACC duct to the LPTACC manifold
– Duct attaches to manifold at 2:00 and 8:00 position
• Manifolds blow air around LPT case
LPTACC - DESCRIPTION
Issue: 4/9/2011
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0
LPTACC - DESCRIPTION
• LPTACC valve consits of:
– Valve body
– 2 RVDT connectors (Rotational Differential Transducer)
– Fuel manifold mount flange
– Actuator
– Butterfly valve in the body
• Valve Controls fan air discharge to the LPT case
• Controls the thermal expansion of LPT case
– This keeps the LPT blade tip clearance at the minimum
– For better fuel efficiency
75-22-00 LPTACC - FUNCTIONAL DESCRIPTION
Issue: 4/9/2011
13
1
LPTCC
Issue: 4/9/2011
13
2
75-22-00
LPTACC - FUNCTIONAL DESCRIPTION
• EEC monitors:
– data from the CDS/DEU: PT, P0, TAT
– and engine parameters: N1, EGT
• EEC measures control valve actuator position for fan air discharge
• EEC sends commands to HMU EHSV to supply servo fuel pressure to
operate the valve
• EEC monitors through RVDT’s the new position of the valve actuator
–When position agree with EEC commanded position, EEC sends null signal
to HMU
– HMU will null servo fuel pressure to keep valves in new position
Inst. Note: Fail-safe = 35% open
ILCBT - ENGINE AIR
Issue: 4/9/2011
13
3
TBV SYSTEM
• Parts of TBV system:
– TBV valve
– TBV manifold
• TBV at 6:00 position on HPC case
– Open Fan cowls and T/R halves to get access to TBV system
• TBV adjusts HPC 9th stg air discharge to increase HPC stall margin
during engine start and rapid accel
75-23-00 TBV SYSTEM - FUNCTIONAL DESCRIPTION
Issue: 4/9/2011
13
4
75-23-00
TBV - FUNCTIONAL DESCRIPTION
• EEC monitors N2 speed + acceleration and A/C data
• EEC schedules position of the TBV valve (OPEN or CLOSED)
– OPEN During start then CLOSED at N2 idle
– OPEN During Accell when N2 < 80%
– CLOSED for accell when N2 > 80%
• EEC sends commands to HMU EHSV to supply servo fuel pressure to
operate the TBV
• EEC monitors the TBV position through 2 LVDT’s
– fwd LVDT connector = Ch. A - rear LVDT connector = Ch. B
–When positions agree with EEC required position, EEC sends signal to HMU
– HMU will null servo fuel pressure to keep valve in new position
HPTACC
Issue: 4/9/2011
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5
TBV
Issue: 4/9/2011
13
6
75-31-00
VSV SYSTEM
• (VSV) Variable Stator Vane system components:
– 2 VSV actuators
– 2 bellcrank assembly
– 4 actuation rings
– VSV
• Left VSV actuator and bellcrank at 8:00 on HPC case
• Right VSV actuator and bellcrank at 2:00 on HPC case
• VSV system adjusts air flow to increase HPC efficiency and stall margin
• VSV Controls the position of IGV + HPC stg 1, 2, 3 stator vanes
VSV - COMPONENT LOCATION
Issue: 4/9/2011
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7
VSV ACTUATOR
• VSV actuators move IGV and 3stg VSV’s
• VSV actuators use HMU servo fuel pressure to move VSV vanes
• Head port and Rod port connected to fuel line
• LVDT connectors for actuator control loop to the EEC
– Right actuator LVDT, channel A
– Left actuator LVDT, channel B
• You can replace one actuator or both
– Each connects to 1 bellcranck
– no line adjustment
– Actuators are interchangeable
Instr. Note:
• the rod port opens VSV, head port closes the VSV
75-31-00 VSV - FUNCTIONAL DESCRIPTION
Issue: 4/9/2011
13
8
VSV - FUNCTIONAL DESCRIPTION
• EEC monitors:
ambient P0 from the CDS/DEU and N2 speed and T25 (Comp. Inlet. T)
• EEC controls position of VSV actuators
– VSV closed at idle N2 (60%)
– VSV move to more open when N2 increases
– VSV full open for N2>~95%
• EEC sends commands to HMU EHSV to supply servo fuel pressure to
operate the actuators
• EEC monitors through LVDT control loop the new position of the VSV
actuators and compare to sensor-feedback model
–When position agree with EEC command, EEC sends null signal to HMU
– HMU will null servo fuel pressure to keep VSV in new position
Inst. Note: EEC takes sensor feedback model when loss of both channel inputs
75-31-00 VBV SYSTEM
Issue: 4/9/2011
13
9
75-32-00
VBV SYSTEM 1/2
• VBV system consists of:
– 2 VBV actuators attached on rear face of fan frame
– 1 Actuation ring
– 10 Bleed doors + 2 Master doors
• left VBV actuator at 10:00 position
• right VBV actuator at 4:00 position
– Actuators are attached to the actuation ring which link the VBV doors
• It controls 12 doors which let LPC air discharge that goes to secondary
airflow during fast decell to prevent LPC stall
– Keeps also unwanted material out of HPC at low engine speed or during
T/R operation
VBV SYSTEM (continued)
Inst Note: 2 pages commentaires pour 1 slide projetée
Issue: 4/9/2011
14
0
75-32-00
• EEC uses A/C and engine data to schedule the VBV position
Inst. Note: VSV position, N1 & N2 speed, TRA position from the CDS/DEU
– EEC sends electrical signal to move EHSV in the HMU to deliver fuel
pressure that moves the VBV actuator
– EEC monitors through LVDT control loop the new position of the VBV
actuators and compare to sensor-feedback model
–When position agree with EEC commanded position, EEC sends a null
signal to HMU
• HMU will stop servo fuel pressure to keep VBV in the new position
Inst. Note:
• EEC takes sensor feedback model when loss of both channel inputs
• when VSV open, VBV close, and vice-versa
• VBV are more open when:
– Rapid decel
– T/R operation
VBV ACTUATOR
VBV SYSTEM continued 2/2
Issue: 4/9/2011
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1
VBV ACTUATOR
• Fuel pressure from the HMU is delivered to either the head or the rod
ports of the actuators
• The two actuators move the actuation ring
– Pressure to the head side drives the VBV doors to the open position
– Pressure to the rod side drives the VBV doors to the closed position
• 1 LVDT on each actuator provides VBV position feedback to the EEC
– Right actuator LVDT to channel A
– Left actuator LVDT to channel B
Inst. Note:
– VBV actuators are interchangeable
– To get access a VBV actuator, you must remove a fan duct panel
75-32-00 VBV DOORS
Issue: 4/9/2011
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2
75-32-00
VBV DOORS
• In the fan frame:
– 12 VBV doors (Inst. Note: New design, Square VBV doors with actuation rings)
– Bellcranks
– Actuation ring
• Let LPC air discharge to go to Secondary airflow
• You must remove fan duct panels to get access to the VBV doors
• VBV actuators operate the two master VBV doors
– Longer Linkage (bellcrank) on the 2 master doors operate the actuation ring
– The 2 master doors are interchangeable
• Actuation ring operates the 10 remaining VBV doors
TBV SYSTEM
Issue: 4/9/2011
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3
ILCBT - ENGINE AIR
• Introduction:
– Turbine clearance control (HPTACC, LPTACC)
– Compressor air discharge control (VSV, VBV, TBV)
• HPTACC operation - control clearance HPT shroud/rotor with 9th and
4th stg air
• LPTACC operation - control LPT case clearance with fan air - never
totally closed
• VSV operation - control HPC airflow relative to N2 with 2 actuators
moving IGV + 3 first HP stator vanes
• VBV operation - control LPC air going to HPC with 2 actuators and 12
doors - function of VSV position
• TBV operation - bleed 9th stg air into 1st stg LPT nozzle with open or
closed valve
75-00-00 GO TO SHOP ENGINE
Issue: 4/9/2011
14
4
GO TO SHOP ENGINE - ENGINE AIR
Show :
• VSV actuator/bellcrank (8:00 on HPC)
• VBV actuator (4:00 and 10:00) - doors - clevis rod on master -
actuation ring ?
• TBV valve (6:00 on HPC) - manifold 9th stg air discharge
• HPTACC valve (3:00 on HPC) - manifold 9th stg air discharge
and 4th stg air discharge - HPT shroud on chart
• LPTACC valve (4:00 on HPC) - duct attached to manifold at 2:00 and
8:00 on HPC - scoop in the Fan Fram
OBJECTIVES: Describe/locate engine air systems components
75-00-00 ENGINE OIL - INTRODUCTION
Issue: 4/9/2011
14
5
CFM56-7 LINE & BASE COURSE OUTLINES
1. Maintenance Documents
2. Power Plant General (71)
3. Engine Exhaust (78)
4. Engine General (72)
5. Fuel and Control System (73) (SAC)
5. Fuel and Control System (DAC)
5. Engine Electrical Wiring Harnesses
6. Air System (75)
7. Ignition System (74)
8. Start System (80)
9. Oil System (79)
10. Engine Indicating System (77)
11. Engine Fault Isolation - CDU Messages
IGNITION 74-00-00 SYSTEM - INTRODUCTION
Issue: 4/9/2011
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6
IGNITION SYSTEM - INTRODUCTION
• Supply electrical sparks in the combustion chamber
• 2 ignition systems that operate independently
• Usual system operation is manual
• EEC can turn on ignition automatically when EEC sees possible
flameout condition
• Ignition used
– During engine ground start
– Usually, pilots turn ignition on for take-off and landing
– Pilots also turn ignition on in bad weather condition
– or for in-flight starts
74-00-00 IGNITION - GENERAL DESCRIPTION
Issue: 4/9/2011
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7
IGNITION - GENERAL DESCRIPTION
• Ignition system is composed of: (Inst. Note: will be detailled later)
– Ignition exciters - Air manifold
– Ignition leads - Igniters
• EEC control of the ignition system is based on cockpit inputs:
– Ignition selector switch - Start switch - Start lever
• Alternating current (ac) is provided by A/C transfert buses to EEC
– The ac transfer bus supplies power for the left ignition system
– The ac standby bus supplies power for the right ignition system
• EEC sends voltage to the ignition exciter
• Exciter converts Alternating current to Direct current (DC) voltage
and sends high energy pulses through the ignition leads and igniters
Instr. Note: right system must be operational for dispatch (standby bus)
– Engine ground starts require operation of only 1 igniter
IGNITION 74-00-00 - FUNCTIONNAL DESCRIPTION
Issue: 4/9/2011
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8
IGNITION - FUNCTIONAL DESCRIPTION - slide 1/7
• Ignition selector switch for:
– Right left or both igniter selection
• EEC receives digital signal from CDS/DEU through ARINC 429 data bus
– for GRD/CONT (Ground/Continuous)
– and FLT (Flight start)
• And analog signal from start switch for ENGINE START CONTROL
– for GRD/CONT
– and FLT
Inst. Note: - Ground start sends electrical signal to start valve
- If digital signal not available, analog is used
• Each channel has internal switches for both igniters
• On this sequence, the engine 1 start switch is on the OFF position
– NO START COMMAND all switches opened
IGNITION - FUNCTIONAL 74-00-00 DESCRIPTION - slide 2
Issue: 4/9/2011
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9
IGNITION - FUNCTIONAL 74-00-00 DESCRIPTION - slide 3
IGNITION - FUNCTIONAL DESCRIPTION - slide 2/7
For this sequence:
• Right ignition is selected
• Start switch is turned on the GRD position
– Ground start sends 28V DC to sart valve
– Engine start control solenoid maintains start switch in GRD until start lever
in idle and 55% N2 rpm is obtained
– EEC engine start control is activated
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• CDS/DEU send ignition selection command to EEC
– Right igniter was selected
– Igniter is activated when the start lever is in idle
IGNITION - FUNCTIONAL DESCRIPTION - slide 3/7
IGNITION - FUNCTIONAL 74-00-00 DESCRIPTION - slide 4
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• Start lever passes in idle
• A/C transfert bus power supply to EEC and ignition exciter
IGNITION - FUNCTIONAL DESCRIPTION - slide 4/7
IGNITION - FUNCTIONAL 74-00-00 DESCRIPTION - slide 5
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2
When N2 rpm is at 55%
• Then Engine start control solenoid turns the start switch on the OFF
• Igniter is OFF
IGNITION - FUNCTIONAL DESCRIPTION - slide 5/7
IGNITION - FUNCTIONAL 74-00-00 DESCRIPTION - slide 6
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IGNITION - FUNCTIONAL 74-00-00 DESCRIPTION - slide 7
IGNITION - FUNCTIONAL DESCRIPTION - slide 6/7
When start switch selected on Continuous:
– Selected igniter activated on continuous
• This position is selected for T/O and landing in case of bad weather
condition according to Flight procedure
Inst. Note:
– This mod can be selected manually by the crew
– Or automatically set by the EEC: from 7BJ software configuration and
upgraded DEU only
• In that case the OFF position becomes AUTO
– During takeoff and landing, when TRA is less than 32 ° or greater than 50° on
ground
• This feature is disabled
– below 20% N2
– WHEN PS3 below 175 psia & a/c below 18.000 ft (5490m) & Anti ice selected
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IGNITION - FUNCTIONAL DESCRIPTION - slide 7/7
For flight restart:
• Engine start switch selected on FLT position
• EEC then activates both left and right igniters
IGNITION EXCITERS
74-00-00
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5
IGNITION EXCITERS
• Exciters boxes are located on the aft fan case at 5:00
– Upper exciter supply power to right igniter
– Lower exciter supply power to left igniter
• Electrical connectors on Front provide aircraft input power
• Electrical connectors on Rear provide high voltage output power to
igniter plugs
– Provide a 14.000 to 18.000 volts DC output (~1 pulse/sec.) to igniters
– Circuit elements isolate the unit from interference with aircraft electronic
– FOR SAFETY: BLEED RESISTOR IS PROVIDED TO DISSIPATE ANY
RESIDUAL CHARGE FROM THE CAPACITOR
IGNITION LEADS
74-00-00
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6
IGNITION LEADS
• The 2 ignition leads consist of copper conductors with silicon insulation in
a flexible conduit
• Leads run from the ignition exciters on the fan case
– Down to air manifold at 6:00 bottom of HPC module
– and connect to the igniters on the combustion case
• They deliver High voltage, low energy electrical pulses to the igniters
• Rear half of Ignition leads are cooled with booster air:
– Booster air supplies air cooling to the air manoifold at 6:00 rearward the fan
case
– airflow through an air jacket/conduit
– discharged through bleed ports just above the lead at ignitor plug connection
IGNITERS
74-00-00
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IGNITERS
• They are located at 4 and 8 O ’clock positions
• Igniters provide electrical sparks required to start or maintain
combustion
• A surface gap at the tip discharges High voltage electrical pulse to
produce spark
• 2 attached shroud halves protect Installed plug from heat
(Inst. Note: refer to previous slide for localisation)
– Booster air cooling flows over the plug and under shrouds, exit against the
combustion case
– Shroud halves are attached to the plug by a hose clamp.
IGNITION CONTROL
74-00-00
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IGNITION CONTROL
• Ignition control from Flight compartment inputs:
– Ignition selector switch selects LEFT RIGHT or BOTH igniters
– Start switch activates start valve (air starter)
– Start lever allows power activation of igniters
opens the HPSOV for fuel supply to the combustion
– CDS/DEU controls ignition operation and condition to EEC
• EEC control for the ignition system is based on cockpit inputs:
IGNITION/START CONTROL
74-00-00
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9
IGNITION/START CONTROL
TO SUMMARISE:
• There are 3 selector switch positions:
– Right left or both igniter operation
• There are 4 start switch positions for engine start:
– GRD (ground start): start engages and ignition and fuel are supplied when
the start lever is moved up to IDLE position
– CONT (Continuous): Selected by flight crew for T/O, approach, landing and
bad weather conditions (when AUTO configuration not available)
– OFF or AUTO (depends on DEU/EEC software configuration):
No ignition, unless the EEC sees a possible flameout condition
– FLT (flight): Both igniters are automatically set by the EEC for restart.
74-00-00 ENGINE STARTING
Boeing tip letter 737MT73-001 for trouble shooting
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Ignition CDU display
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1
CFM56-7 LINE & BASE COURSE OUTLINES
1. Maintenance Documents
2. Power Plant General (71)
3. Engine Exhaust (78)
4. Engine General (72)
5. Fuel and Control System (73) (SAC)
5. Fuel and Control System (DAC)
5. Engine Electrical Wiring Harnesses
6. Air System (75)
7. Ignition System (74)
8. Start System (80)
9. Oil System (79)
10. Engine Indicating System (77)
11. Engine Fault Isolation - CDU Messages
STARTING 80-00-00 SYSTEM - INTRODUCTION
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ENGINE STARTING - INTRODUCTION
• Starting system uses Pneumatic power sources to turn N2 rotor during
engine start:
– APU (Auxilary Power Unit)
– Ground Power Unit
– Opposite engine running
• System can operate on ground and in flight
80-00-00 START SYSTEM
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3
START SYSTEM - GENERAL DESCRIPTION
• Consists of:
– Pneumatic starter duct assembly
– Start valve
– Starter
• Flight compartment switches and DEU’s control the starter system
• The starter system provide sufficient torque to accelerate the N2 (HP
system) to a speed at which a combustion and a self sustaining
Rotational speed (rpm) occurs.
– Start system is used also for engine cranking for dry and wet motoring
Inst. Notes:
• GRD position engages starter, other positions do not
• EEC has engine starting protections for hot and wet (no ignition) starts
• APU/EEC receives signal to schedule IGV’s for max pneumatic output
• DEU’s show start valve open on CDS
80-00-00 START VALVE
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4
Start control
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5
STARTING OPERATION
Inst. Note: Summary controls/indications for engine start
• Flight compartment controls:
– Start switch -Ignition selector switch - Engine start lever
• Engine parameters monitored by the operator
– N2 - Oil pressure - N1 - Fuel Flow - EGT
• Engine start:
– Set ignition selector switch L or R
– Start switch to GRD
– Look for message and engine parameters: « START VLV OPEN », N2 speed,
Oil P, N1 rotation.
– From 25% N2 moves Start lever to idle
– Look for engine parameters: FF, EGT/N2 increase proportional until N2>55%
– Make sure start switch goes back to the OFF at 55%.
WARNING: OBEY SAFETY PROCEDURE AS REQUIRED IN THE BMM.
INJURY TO PERSONNES OR DAMAGE TO AIRPLANE AND GROUND
EQUIPMENT CAN OCCUR
80-00-00 ILCBT - START CONTROL
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CDU display
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7
START VALVE
• Start valve is on the Fan frame, above the starter
• It is electrically controlled by EEC using 28 vdc from the aircraft battery
bus
–When solenoid energized, duct pressure is greater than the spring force and
the valve opens
– Pneumatic power comes from APU or GPU or Other engine bleed
• A small hole in the left fan cowl provide access to the manual override of
the start valve
– A 3/8 inch square drive tool is used
– Visual indication shows valve position
• CAUTION: START SYSTEM MUST BE PRESSURIZED DURING
MANUAL OPERATION
– Can damage valve
STARTER
80-00-00
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STARTER
• Starter is a single flow axial air turbine
– Clamped to fwd face of the AGB by a hinged “V” coupling clamp
• Starter is pneumatically controlled by the start valve
–When start switch commands the start valve to open:
• airflow passes through starter turbine creating rotation
• turbine turns gears and engages through ratchet system the rotation of the output
shaft to the AGB
• AGB then turns the N2 (core engine)
– At 55% N2 the start valve will close and cutoff starter
• Then sprag clutch disengages and output shaft of the AGB is driven by AGB N2
Inst. Note: Starter duty cycle
• Normal operation = limited to 2 mn with 10 break between attempts
• Extended operation = 15 mn work / 2 mn break / 15 mn w / 10 mn b / 5 mn w.
80-00-00 STARTER SERVICING
SB 80-005
P07/P08 starter
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STARTER SERVICING
• Starter is self lubricated by the AGB oil system
– A small quantity of oil stays with the starter as the rest returns in AGB
• Only installation of a new starter requires the addition of a small
quantity of oil (300 cc)
– For servicing respect the AMM and use the same engine oil brand that is
used for the engine
– A TEDECO servicing tool can be installed in the magnetic plug housing of
the starter
80-00-00 START CONTROL
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Engine starting operation
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ILCBT - STARTING
• ALWAYS FOLLOW AMM PART 2 PROCEDURES (CHAPTER 71) TO
START ENGINE
• LESSON OUTLINE BELOW
– NORMAL START
– HOT START (EEC ABORTS ENGINE START. EEC CLOSES FUEL
METERING VALVE)
– HUNG START (NO IGNITION) CAN ALSO BE CONSIDERED LIKE WET
START
– OTHER EEC AUTO PROTECTION FOR:
• ROLL BACK PROTECTION
• STARTING RED LINE = 725°C
80-00-00 SHOP - START SYSTEM
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80-00-00 START CONTROL - WET
START CONTROL - GRD - 1/5
• With pneumatic and electrical power source available,
• Engine start switch in the GRD position:
– APU ecu receives signal to open APU inlet guide vanes (increase airflow)
– EEC/CDS/DEU monitor start and engine parameters « LOW OIL PRESSURE »
– Start valve solenoid energizes and valve opens
– CDS/DEU controls start valve annonciation « START VLV OPEN »
– Starter clutch engages and engine N2 rotor turns
– Solenoid in the P5 panel energizes to hold switch in GRD position
– At ~= 25% N2, You move Start lever in idle position = add fuel and ignition for
engine combustion
– At 55% N2, CDS/DEU remove the electrical ground for the start switch solenoid
• Start switch goes to the OFF or AUTO position (post SB73-A026)
• Start valve solenoid deenergizes and valve closes
Inst. Notes: Typical idle parameters:
N1~20%, N2~59%, EGT~410°C (f(bleed and OAT)) Fuel Flow~600 lb/h
Inst Note: 5 pages commentaires pour 1 slide projetée
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START CONTROL - WET START - 2/5
• Engine wet start protection (also called HUNG start):
– EEC stops engine start if EGT does not rise (more than 42°C)
in 15 s after you have moved the start lever in idle position
in 20 s if TAT < 2°C
• EEC stops fuel flow (FMV)
• EEC turns Off ignition
– CDS/DEU show fault message on CDU
Inst. Notes:
– The operator continues motoring the engine for 60 s to purge fuel
– Manually turns the start switch to the OFF position
80-00-00 START CONTROL - HOT START
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4
START CONTROL - HOT START - 3/5
• Engine hot sart protection:
– EGT digital indication flashes when EEC sees a possible hot start (725°C)
In fact when the sliding EGT curve characteristics is exceeded
Inst. Note: limit varies depending on engine condition during start procedure
– EEC immediately stops fuel flow and ignition, if limit is exceeded
– EGT digital display continues to flash until you move start lever to CUTOFF
• This system operates on the ground only
• Operator should normaly control engine parameters
– to anticipate any hot start condition
– and put the start lever in the cutoff position before EEC does
START 80-00-00 CONTROL - IN FLIGHT START
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START CONTROL - IN FLIGHT START - 4/5
• Windmill in flight start:
– Start switch in FLT position for a windmill start
• Starter does not operate
• When CDS tells the crew that engine is out of windmill restart condition
– message « X-BLEED START » shows on CDU above N2 indicator
– In this situation, the crew moves the start switch in GRD to use the starter
assistance for restart
80-00-00 START CONTROL - AUTO RELIGHT
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START CONTROL - AUTO RELIGHT - 5/5
• EEC turns ignition ON in automatic when:
– Start lever in idle
– N2 above 51%
– EEC does not receive an input to slow engine speed
– EEC sees the engine speed decrease
NOTE: Automatic relight function only in flight
80-00-00 START CONTROL
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OBJECTIVES: DESCRIBE/LOCATE ENGINE STARTING SYSTEM COMPONENTS
GO TO SHOP ENGINE - STARTING 1/2
• SHOW
– START AIR VALVE
– STARTER
– MANUAL OVERRIDE
– CLOSE LEFT HALF T/R
– OPERATE START VALVE (TRAINING SCHOOL ONLY ! - NO AIR
PRESSURE !)
– SHOW PLACARDS
• SHOW STARTER - DRAIN/FILL PORT
80-00-00 SHOP - START SYSTEM 2/2
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OBJECTIVES: DESCRIBE/LOCATE IGNITION SYSTEM COMPONENTS
GO TO SHOP ENGINE - STARTING 2/2
• SHOW IGNITERS
– RIGHT IS NECESSARY FOR DISPATCH (STANDBY BUS)
• SHOW IGNITION LEADS
• SHOW AIR MANIFOLDS - BOOSTER AIR
• SHOW SPARK IGNITERS
• WARNING: FOLLOW AMM PROCEDURES - HIGH TENSION !
80-00-00 ENGINE INDICATING
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CFM56-7 LINE & BASE COURSE OUTLINES
1. Maintenance Documents
2. Power Plant General (71)
3. Engine Exhaust (78)
4. Engine General (72)
5. Fuel and Control System (73) (SAC)
5. Fuel and Control System (DAC)
5. Engine Electrical Wiring Harnesses
6. Air System (75)
7. Ignition System (74)
8. Start System (80)
9. Oil System (79)
10. Engine Indicating System (77)
11. Engine Fault Isolation - CDU Messages
79-00-00 OIL SYSTEM - INTRODUCTION
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79-00-00
OIL SYSTEM - INTRODUCTION
• The oil system lubricate, Cool & Clean bearings and gears of the
engine
3 Subsystems:
Storage
Distribution
Indicating
OIL DISTRIBUTION
3 circuits:
supply
scavenge
vent
3 functions:
lubricates
cool
clean
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Oil storage
• BIDON, à DEGAGER
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2
OIL STORAGE - OIL TANK
• Oil tank on the fan case at 3:00 position
• keeps sufficient oil for a continuous supply to the distribution circuit
• Removes also the air from scavenged oil
• Oil tank components and purposes:
• Oil quantity transmitter sends oil level to CDS/DEU (see details later)
• Gravity fill port and a pressure servicing fill port
• Oil scupper to drain oil which falls during gravity servicing
• Oil level sight gage for visual check
• Oil supply at the base of tank, is gravity fed to the lube unit line
• Oil scavenge line enters the top of the tank through air oil separator
• Drain plug to scavenge the oil tank
• During operation, the oil level will decrease as engine N2 rpm
increases
• at engine start, level may decrease as much as 1 gal. (4 L)
• at TO, level may decrease as much as 0.5 gal. (2 L)
• this is partially recovered during decell. And completely at engine shut down
79-10-00 OIL TANK SERVICING
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3
OIL TANK SERVICING
• Oil tank is fully serviced when oil level reaches the shaded area of the
sight glass
Full serviced oil tank capacity 22.1 us qts (20,1 L - eng. 1) (20.4 L - eng. 2)
• Servicing insures sufficient amount of oil to sustain normal operation
– Manual filling through oil gravity fill port or
– Pressure filling through pressure servicing ports with pressure servicing unit
• Do not mix types 1 and type 2 oil brands - Part II of the Maintenance
Manual provides information about approved oil brands
• Oil check and servicing not less than 5 mn and not greater than 30mn
after shutdown (Inst. Note: 100°C delta T = +/- 1,6 L for 20 liters)
– This prevent over servicing
– overserviced oil is blown overboard through engine vent system
Inst. Note: when you open the filler cap, it is recommended to do a visual and
smell test to identify potential fuel contaminant in the oil
79-10-00 ANTI-LEAKAGE VALVE
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4
79-20-00
OIL DISTRIBUTION
• 3 Distribution circuits :
• Supply: sends oil to lubricate bearings and gears.
• Scavenge: oil returns to oil tank.
• Vent: balances the internal air pressure from the engine sumps, gearbox and oil
tank.
– Oil Supply goes from oil tank, to anti-leakage valve, to lube unit to supply filter
• Pressurized and filtered oil goes to engine bearing sumps and gearboxes
– Oil Scavenge goes from forward and rear sumps and gearboxes to lube unit
through 3 chip detectors before going to 3 scavenge pumps (collect ferrous
and non-ferrous material)
• Oil from scavenge pumps goes to scavenge oil filter, goes to oil/fuel heat exchanger
then to Servo Fuel Heater
• Oil leaves the Servo Fuel Heater & returns to oil tank
– Unwanted air pressure from the oil system is vented overboard:
• Oil tank vents into fwd sump;
• Fwd sump and aft sump to atmosphere
OIL TANK
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LUBRICATION UNIT
• Lubrication unit mounted on aft side of AGB at 7:00 position by a V-band
clamp
• 2 functions:
– Pressurizes oil to supply engine bearings and gears
– Scavenges oil for reuse
Inst. Note: Locate the lube unit components on the figure
• Lube unit driven by AGB
• Output pressure is not controlled by the lube unit
– As engine speed changes, pressure changes (Inst. Note: 76 psi at 6110 rpm)
– Pressure relief valve opens when pressure exceeds the limits
• That diverts oil into the AGB/TGB scavenge pump
Instr. Note: PRV opens if P > 305 psi
79-20-00 OIL SUPPLY FILTER AND POP-OUT
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6
OIL SUPPLY FILTER and POP-OUT INDICATOR
• Supply oil filter located in housing of lubrication unit
– Removes and holds unwanted material from the supply oil to prevent
contamination of downstream oil circuits
– Supply oil filter cartridge made of paper material is discardable after use and
inspection (Inst. Note: 44μm)
• Red pop-out indicator shows, when filter clogged, before the bypass
valve opens
– Remove glass dome to reset indicator button
Inst. Note: POP-OUT if P > ~ 26 psi
• Bypass valve lets oil to pass around a clogged filter and continue to flow
Inst. Note: - Bypass when P > ~ 32 psi
- there is no bypass indication in flight compartment
79-20-00 CHIP DETECTORS
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7
CHIP DETECTORS
• There are 3 chip detectors; 1 for each sump, as follows:
starting from the front of the engine
– 1st AGB & TGB You read the name of the concerned sump written
– 2nd Fwd sump on the Lube unit housing at each scavenge line
– 3rd Rear sump inlet to help to identify the area of potential failure
CAUTION: Chip detectors are interchangeable.
Remove and TAG (identify) chip detector one at a time. This can prevent an
error in identification of the source of material (debris).
• C.D. are Attached to Lube unit housing secured by a bayonet lock
– Check-valve in the Lube unit prevents oil leakage when chip detector removed
• Chip detectors help to detect potential engine component failure (bearing
or gear), they consists of:
– A magnet to captivate the magnetic material
– A metallic-mesh screen that collects non-magnetic material
(Inst. Note: size > 800 μm)
79-20-00 DEBRIS MONITORING SYSTEM
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8
DEBRIS MONITORING SYSTEM
• DMS is optional and consists of:
– 3 DMS detectors; 1 for each sump, as described for chip detectors
(Inst. Note: DMS detectors fully interchangeable with classic MCD)
– 3 harnesses connect DMS detectors to DMS box
– 1 DMS box at 6:00 on the fan frame provides single input to EEC
– A single harness (J8) links DMS box to EEC, ch B.
• When DMS detector captivates magnetic particles in between 2 ends of the
magnetic plug
– This makes the contact and change the resistance value (like a switch)
(Inst. Note: bridge the gap concept)
– The EEC sends information to CDU:
Maintenance level - “Oil system” Menu selection
Inst. Note:
• Below 130 ohms resistance input,
message displayed to CDU = “DMS REQUIRES INSPECTION”
79-20-00 OIL SCAVENGE FILTER ASSEMBLY
Vue du DMS
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9
MAIN OIL / FUEL HEAT EXCHANGER
• The Heat exchanger mounted on the Fuel pump located at 8:00 position
• It consists of
– A housing which contains the exchanger core
– A cover that holds the core
• The Heat Echanger uses fuel to decrease temperature of the scavenge oil
by the process of convection
– Fuel comes from LP fuel pump and returns to the HP fuel pump
• After passing the Heat echanger scavenge oil returns to oil tank through
Servo Fuel Heater (SFH)
79-20-00 LCBT - OIL SYSTEM
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0
OIL SCAVENGE FILTER ASSEMBLY
• Insures filtration of particles from oil that comes from the sumps and
the 3 scavenge pumps before returning to the oil tank
• The scavenge filter located at 7:00 rear face of the AGB contains:
– Disposable oil filter (Inst. Note: paper filter 25 to 32 μm)
– A filter bowl and the body that contains the filter bypass switch and valve
– A locking ratchet lever prevents filter bowl rotation
• Filter bypass switch for flight deck indication: “OIL FILTER BYP”
Instr. Note:
• When pressure drop at ~ 32 psid for more than 60 seconds
• This message sets for switches desagree for 30sec. On ground only (90sec. After
landing)
• The scavenge oil filter does not have a pop-out indicator
• A bimetallic locking system prevents filter switch actuation at low operating temp.
• Filter bypass valve. Instr. Note: Bypass from ~ 45 psid
• Discard paper filter and packing O ring after removal and inspection
79-20-00 MAIN OIL/FUEL HEAT EXCHANGER
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1
ANTI-LEAKAGE VALVE
• At 6:00 on the fan frame
• Is a pressure actuated,
– A spring closes the valve, when the engine does not operate,
– Pressure connection from the rear sump oil supply line drives the valve to
open
• Prevents to drain oil tank when removing lube unit
– You must drain oil tank before removing anti-leakage valve
• Also acts as “anti-siphon”, prevents the oil to flow from the oil tank to
other oil system by siphon effect
79-20-00 LUBE UNIT
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2
OIL CIRCUIT SUMMARY
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3
OIL INDICATING
• Oil indicating components : (Inst. Note: locate on the figure)
– Oil quantity transmitter on the oil tank
– Oil pressure transmitter on the T/P sensor
– Oil temperature sensor on the T/P sensor
– Oil filter bypass switch on the scavenge oil filter
• Oil indicating components supply oil system data through the CDS to
upper CDU on the P2 panel
Note: Oil quantity transmitter sends data directly to CDS/DEU the 3 other
components send data to CDS/DEU through EEC
– Oil quantity / Oil pressure / Oil temperature / Oil filter bypass
– Optional DMS detector sends information to CDU through EEC
– For maintenance purpose only not during flight operation
79-30-00 OIL QUANTITY TRANSMITTER
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4
OIL QUANTITY TRANSMITTER
• The oil quantity transmitter is an electrical resistance sensor
– Uses a floating magnet and reed switches to show oil quantity in oil tank
– sends data directly to CDS/DEU’s
• The resistance value received by the CDS is proportional to oil quantity
– Show in % on upper CDU
Inst. Note: Customer can select optional units (quarts or liters)
– Minimum readable is 9.4%
– 100% cockpit is 21.23 quarts (20,1 liters) full tank
Inst. Note: per BMM, Mini dispatch is 60% cockpit = 12 us qts (11.4 L) engine
not running
79-30-00 OIL PRESSURE TRANSMITTER
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5
OIL PRESSURE TRANSMITTER
• The Oil pressure transmitter is part of the T/P sensor assembly
– It consists of 2 sensing elements, each connected to ch A and B of the EEC
– Measures diff. pressure between the supply pump outlet of the lube unit (fwd
sump/TGB oil supply) and the TGB cavity
• It sends electrical signal to EEC
– EEC transmits ARINC 429 data to upper CDU through CDS/DEU
• On CDU, 2 dials indicate oil pressure for each engine
– Analog pointer shows oil pressure in lb/in² (psid)
• Oil pressure limits as follows:
– 1 amber index marker shows amber limit: varies as fonction of N2 speed
instr. Note: from 13 psid (equal red band) when N2<9688 rpm (mini idle) to 36.3 psid
when N2>15183 rpm
– 1 red line index marker shows limit: =< 13 psid
– For each engine when in red band, “LOW OIL PRESS” amber message shows
on CDU above dial indicators
• Continuous during start/shut down or when oil pressure below red line
• Flashes 10 sec then continuous in flight
79-30-00
OIL Pressure diagram, or go to:
OIL TEMPERATURE SENSOR
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6
OIL PRESSURE TRANSMITTER
Inst. Note: Nice to Know; use it as required
23
36.3
13
9688 12500 15183
Red line = 13 PSI
Oil pressure
N2 (rpm)
79-30-00 OIL TEMPERATURE SENSOR
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7
OIL TEMPERATURE SENSOR
• The Oil temperature transmitter is part of the T/P sensor assembly
– It consists of 2 sensing elements in a single housing and 1 connector
• each element connects to channel A and B of the EEC
– It measures Oil temperature at outlet of lube unit (fwd sump/TGB supply circuit)
• It sends electrical signal to EEC
– EEC transmits ARINC 429 data to upper CDU through CDS/DEU
• On upper CDU, 2 dials indicate oil temp for each engine
– Pointers show temp in °C
• Oil temp limit:
– amber band: T > 143°C = operation 15 mn prior to engine shut down
– red band: T > 158 °C = shut down
79-30-00 OIL FILTER BYPASS SWITCH
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8
OIL FILTER BYPASS SWITCH
• Switch is normally open switch and part of scavange oil filter
• Measures Delta P between inlet/outlet of scavenge filter
• Closes if 29 < P < 33 psid before filter bypass opens (39 < P < 46)
• Signal is sent to EEC then to CDS/CDU with message displayed
“OIL FILTER BYP”
– Flashes for 10 sec, then continuous
– Confirmation delay ~60 s
– This flashing feature is inhibited during takeoff and landing
79-30-00 T/R - INDICATING SYSTEM
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9
ILCBT - OIL SYSTEM
– System components
– Sumps identification
• Oil supply suction from pressure pump initially opens anti-leak valve
– Supply oil goes to supply filter and lubricate bearings and gears in sumps
– Pressure keeps anti-leak valve fully open
– Pressure relief valve opens if too much pressure
• Scavenge pumps remove oil from sumps through chip detectors
• Oil goes to scavenge filter to oil/fuel heat exchanger to oil tank
• Vent - oil tank to AGB/TGB to fwd sump to rear sump to atmosphere
• Non normal shows filters and cooler bypass conditions
– Filter bypass indication shows before actual bypass
– 60 sec delay before scav. Bypass indication on CDS
79-20-00 GO TO SHOP - OIL SYSTEM
Issue: 4/9/2011
20
0
GO TO SHOP - OIL SYSTEM
• Show:
• Oil tank - sight gage - oil qty trans. - Drain plug
• Anti leak valve - pressure connection
• Lube unit - supply filter/pop-out indic. - Chip detectors
• Supply lines to sumps
• Scavenge lines to lube unit
• Scavenge oil filter - ratchet - bypass switch
• Main oil/fuel heat exchanger
• T/P sensor - temp sensor - pressure sensor
Objectives: describe/locate engine oil systems components
(distribution/indicating) onto the engine
79-00-00 IGNITION
Issue: 4/9/2011
20
1
CFM56-7 LINE & BASE COURSE OUTLINES
1. Maintenance Documents
2. Power Plant General (71)
3. Engine Exhaust (78)
4. Engine General (72)
5. Fuel and Control System (73) (SAC)
5. Fuel and Control System (DAC)
5. Engine Electrical Wiring Harnesses
6. Air System (75)
7. Ignition System (74)
8. Start System (80)
9. Oil System (79)
10. Engine Indicating System (77)
11. Engine Fault Isolation - CDU Messages
INDICATING 77-00-00 SYSTEM - INTRODUCTION
Issue: 4/9/2011
20
2
Common Display System
Inst. Note: NICE TO KNOW, not planned in the course
• Acquires data from systems on the Airplane including engine controls
• Formats the data,
presents them to the crew on one of the 6 display units
• Serves as Data acquisition, multiplexor / demultiplexor and
dissemination ressources for data between EEC and various airplanes
components
1 Receives digital and analog data from engine and display them on the DU
2 Reads position of certain flight compartment switches and transmit them
digitally to the EEC
3 Reads digitaly data from both EEC channel and operates several flight
compartment indications from EEC discret and outputs
4 Extracts data from FMC and ADIRU and send them to EEC
5 Buffers the four databuses from EEC so that the FMC receives EEC data
73-21-00 ENGINE CONTROL - INTERFACES
Issue: 4/9/2011
20
3
Glareshield P7 / Master caution
Issue: 4/9/2011
20
4
Engine display
Issue: 4/9/2011
20
5
P9 panel / CDU
Issue: 4/9/2011
20
6
Forward overhead panel
Issue: 4/9/2011
20
7
Aft overhead panel / EEC Control light
Issue: 4/9/2011
20
8
AVM / Engine indicating
• The EEC converts N1 / N2 / EGT analog signals to digital and sends
data to DEU
• The engine indication system continuously supplies data to the CDS
• AVM conditioner receives analog signals from:
– N1 , N2 , #1 bearing vibration, fan frame compressor case vertical vibration
(FFCCV)
• AVM conditioner then sends a digital vib signal to the DEU and FDAU
(Flight Data Acquisition Unit)
• The DEU shows the above parameters on one of the DU’s
• DEU’s normally uses digital signals from EEC through 429 bus.
– DEU’s can use analog signals if cannot read digital signal or if digital
signals are not available
77-00-00 N1 INDICATION
Issue: 4/9/2011
20
9
AIRCRAFT VIBRATION MONITORING SYSTEM
• Aircraft Vibration Monitoring (AVM) consists of:
– AVM conditioner
– No 1 Bearing accelerometer sensor
– Fan Frame Compressor Case sensor (FFCCV)
• AVM Sends engine vibration data to the DEU and the FDAU
• The DEU shows engine vibration on CDS
• AVM also stores engine vibration information
• Signal conditioner uses:
– No 1 bearing accelerometer sensor
– FFCCV sensor analog signals
– N1 rpm
– N2 rpm
77-31-00 N1 BEARING ACCELEROMETER
Issue: 4/9/2011
21
0
N1 BEARING ACCELEROMETER
• N1 bearing accelerometer is attached to #1 and #2 bearing support.
• It consists of Piezoelectric crystal wafers and collector plates
• Sensitivity is rated at 100 picocoulombs/g
– The low signal strength requires specially shielded leads, securely
supported to avoid and prevents unwanted external signals
– A signal conditioner is required to process accelerometer output to a
useable strength for flight deck display
77-31-00 FFCCV ACCELEROMETER
Issue: 4/9/2011
21
1
FFCCV ACCELEROMETER
• FFCCV is attached to the mid box structure of the fan frame at 3:00.
• It consists of Piezoelectric crystal wafers and collector plates
• Sensitivity is rated at 100 picocoulombs/g
– The low signal strength requires specially shielded leads, securely
supported to avoid and prevents unwanted external signals
– A signal conditioner is required to process accelerometer output to a
useable strength for flight deck display
77-31-00 AVM SIGNAL CONDITIONER
Issue: 4/9/2011
21
2
AVM SIGNAL CONDITIONER
• Is mounted in the Electronic Equipment compartment
• It calculates engine vibration
• Isolates system failures
• Stores historical data for failure and vibration
77-31-00 FUEL INDICATING COMPONENTS
Issue: 4/9/2011
21
3
Endevco / signal conditioner
Issue: 4/9/2011
21
4
Vibrometer / signal conditioner
Issue: 4/9/2011
21
5
ILCBT / Secondary parameter
Issue: 4/9/2011
21
6
CFM56-7 LINE & BASE COURSE OUTLINES
1. Maintenance Documents
2. Power Plant General (71)
3. Engine Exhaust (78)
4. Engine General (72)
5. Fuel and Control System (73) (SAC)
5. Fuel and Control System (DAC)
5. Engine Electrical Wiring Harnesses
6. Air System (75)
7. Ignition System (74)
8. Start System (80)
9. Oil System (79)
10. Engine Indicating System (77)
11. Engine Fault Isolation - CDU Messages
ENGINE FAULT 77-00-00 ISOLATION - INTRODUCTION
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7
Engine fault isolation system
Issue: 4/9/2011
21
8
COMMON DISPLAY UNIT - CDU 1/3
Inst Note: Commencer par FAULT ANNUNCIATION en cliquant sur ce
titre de la slide vous obtenez 6 diapos power point sur le sujet.
• Le retour se fait en cliquant sur la dernière diapo.
• EEC DISPATCH LEVELS
• Fault Dispatch levels have 5 groups:
– group A: NO GO fault
– group B: Short Time Fault = 150 hrs-Q FH
– group C: Long Time Fault = 500 hrs- S/2 FH
– group D: Economic Awarness = No time limitation
– group E: Alternate mode = Check Dispatch Deviation Guide / MMEL
Inst. Note: MMEL = Master Minimum Equipment List
FAULT ISOLATION
Inst Note: 3 pages commentaires pour 1 slide projetée
Flight leg storage
processing
Issue: 4/9/2011
21
9
COMMON DISPLAY UNIT - CDU 2/3
• 2 CDU ’s on the center console of flight compartment
• CDU of the FMC system is used to perform engine history BITE procedure
• Each CDU contains 12 line selec keys (LSK) to select menu items
– 6 left, 6 right
• Some menu items contains more than 1 page : NEXT PAGE/PREV PAGE
are provided
• After powering up the CDU, the initial reference index screen is displayed
• To get access to a specific system maintenance function
– Select MAINT line, the next screen «MAINT BITE INDEX will be displayed
FAULT ISOLATION
Issue: 4/9/2011
22
0
COMMON DISPLAY UNIT - CDU 3/3
• This presentation introduces the CDU/BITE index
Inst Note: 5 slides under PP
• Cliquer 1 fois sur le boitier CDU de la diapo pour activer la présentation
• Les touches actives sont identifiée par la main avec index
• Passer en revue:
– ENGINE>
• ENGINE 1 BITE TEST / INITIALIZING EEC1
– cliquer 2 fois pour avancer les 2 diapos suivantes
• ENGINE 1 BITE TEST RECENT FAULTS, cliquer HISTORY>
• Apparaissent les pages HISTORY 1/4
– Passer en revue les differents ecrans actifs:
• IDENT/CONFIG, utiliser la touche next page
• GROUND TEST
• Sortir en cliquant sur index pour obtenir MAINT BITE INDEX puis sur le
bouton rond à coté de BRT
FAULT ISOLATION
Issue: 4/9/2011
22
1
CFM56-7 LINE & BASE COURSE OUTLINES
1. Maintenance Documents
2. Power Plant General (71)
3. Engine Exhaust (78)
4. Engine General (72)
5. Fuel and Control System (73) (SAC)
5. Fuel and Control System (DAC)
5. Engine Electrical Wiring Harnesses
6. Air System (75)
7. Ignition System (74)
8. Start System (80)
9. Oil System (79)
10. Engine Indicating System (77)
11. Engine Fault Isolation - CDU Messages
MAINTENANCE 71-00-00 DOCUMENTS - INTRODUCTION
Issue: 4/9/2011
22
2
01-00-00
MAINTENANCE DOCUMENTS - INTRODUCTION
• Scheduled maintenance refers to:
– MPD - BOEING 737 task cards and indexes - AMM
• Unscheduled maintenance refers to:
– FRM, Fault Reporting Manual: Entry point
– FIM = Fault Isolation Manual and/or BITE Manual (in the cockpit)
– FIM refers to AMM for tasks
• Dispatch deviation guide: could a/c fly with fault during limited time ?
• AMM may refer to supporting data
Inst. Note: MMEL = Master Minimum Equipment List
MAINTENANCE DOCUMENTS - EXAMPLE
Inst. Note about Dispatch levels:
- No dispatch
- Short time (150 h)
- Long time ( 500 h)
- Economic (no limitation)
- Alternate mode light (refer to MMEL)
Issue: 4/9/2011
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3
MAINTENANCE DOCUMENTS - EXAMPLE - FAILED LRU
• Flight crew uses Fault Reporting Manual (FRM)
– Crew writes the fault code and a brief description of Pb in aircraft flight log.
• Maintenance crew checks Dispatch Deviation Guide
– Decides to fix or defer the problem
• For a fix, maintenance crew uses Fault Isolation Manual (FIM)
or the BITE manual to find the FIM task number
– In the BITE manual,
• task number in observed fault list may have (*): use FIM or BITE for (*) tasks
• Use FIM for tasks that do not have an asterisk
• Maintenance crew does the BITE procedure and gets a maintenance
message from BITE
• Maintenance crew finds FIM task number in a table in FIM or BITE manual
• FIM says to replace the LRU and refer to AMM chapter
• FIM, then, gives the step to verify the fault is corrected
• When corrected, maintenance crew finishes job by completing paperwork
01-00-00 COMMON DISPLAY UNIT -CDU
Format d’1 maintenance message
Issue: 4/9/2011
22
4
Inst. Note: 2 SPCBT’s: 1- TROUBLESHOOTING;
2- INCIDENT RECALL
• Objectives:
– Learn to use the different tools given to troubleshoot an engine
• Scenario:
– EEC control light came on
– Use FIM/BITE manual to find task (2 ways are possible)
– Use CDU to find fault number
– Use FIM to isolate faulty equipment
– Change equipment
– Check that fault is cleared
Inst. note:
– Through this example, explain the “entry point” for troubleshooting is the
FIM (or the bite manual).
– Then follow the procedure.
– It is always the same process !
SPCBT
END OF THE THEORY
Mots de passe students:
1- SCHOOL
2- SNECMA
Issue: 4/9/2011
22
5
OBJECTIVES:
DESCRIBE/LOCATE ENGINE INDICATING SYSTEM COMPONENTS
GO TO SHOP ENGINE
• SHOW N1 SPEED SENSOR - 3 CONNECTORS - CHECK GAP
• SHOW N2 SPEED SENSOR - 3 CONNECTORS
• SHOW EGT SYSTEM - 8 PROBES - HARNESSES
• #1 BRG VIB SENSOR: SHOW WHERE IT IS HIDDEN
• SHOW FFCCV SENSOR
Issue: 4/9/2011
22
6
Thrust increase versus 7B27
10 20 30 40 50 60
Ambient temperature
4
3
2
1
5
N1 limited EGT limited N2 limited
%
Typical T/O condition: Sea level / 0.25 Mn
CFM56-7B27 Thrust increase
Issue: 4/9/2011
22
7
10 20 30 40 50 60
Ambient temperature
7B18
7B26
7B24
7B22
7B20
7B27
7B26/B1
7B24/B1
7B22/B1
CFM56-7B27 Thrust increase
Issue: 4/9/2011
22
8
Fan blade replacement by pairs
Issue: 4/9/2011
22
9
2
14
MW = 208400 cm.g
MW = 208230 cm.g
Blades to be
removed
1
MW = 208120 cm.g
MW = 207920 cm.g
13
15
3
MW = 208620 cm.g
MW = 208500 cm.g
120 cm.g
200 cm.g
170 cm.g
Fan blade replacement by pairs
Issue: 4/9/2011
23
0
2
14
MW = 208500 cm.g
MW = 208480 cm.g
Blades to be
installed
20 cm.g
20 cm.g
10 cm.g
1
13
MW = 207120 cm.g
MW = 207110 cm.g
3
15
MW = 208650 cm.g
MW = 208630 cm.g
Issue: 4/9/2011
23
1
1 36 35
34
33
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18 19 20
21
22
23
24
25
26
27
28
29
30
31
32
360 10 20
30
40
350
340
330
320
310
300
290
280
270
260
250
240
230
220
210
200
190 180 170
160
150
140
130
120
110
100
90
80
70
60
50
2 1
3
4
7
5
6
10
9
8
12
11
14
13
16
15
18
17
20
19
22
21
23
24
200 cm.g
170 cm.g
120 cm.g
190 cm.g
150 cm.g
100 cm.g
10 cm.g
20 cm.g
20 cm.g
Resultant
Vector
calculation
Issue: 4/9/2011
23
2
190 cm.g
150 cm.g
100 cm.g
360 10 20
30
40
350
340
330
320
220
210
200
190 180 170
160
150
140
130
120
110
100
90
80
70
60
50
2 1
3
12
11
13 14
16
15
18
17
20
19
22
21
23
24
190 cm.g
100 cm.g
150 cm.g
Resultant
Vector
calculation
FR = 240 cm.g
Change < or = 3 pairs ?
Resultant < 200 cm.g ?
Issue: 4/9/2011
23
3
Change < or
= 3 pairs
Fan blade change
in pairs
Residual MW
< 200 Cm.g
Yes
Resultant>
600 cm.g
Fan Blade pair
installation
Yes
Mapping procedure
856A3770
“Blamap”
No
No See change more
than 3 pairs
See page 4
Do Static
correction
Yes
Result < 600 cm;g
No
Issue: 4/9/2011
23
4
Fan blade change
in pairs
Change > 3
See previous page No pairs
Residual MW
< 600 cm.g
Yes
Mapping procedure
856A3770
“Blamap”
No : > 600
Fan Blade pair
installation
Resultant Yes : < 600
> 600 cm.g
No
Yes Result < 600 cm.g
Do Static
correction
See page 4
Issue: 4/9/2011
23
5
Fan Blade pair installation
Vibration during
vib survey ?
(customer
convenience)
Do a trim balance procedure
Yes
Return engine to service
No
Issue: 4/9/2011
23
6
• BSV élimination (because flameout margin is sufficient w/o BSV)
• must be accompanied with TBV large bore
• can be verified on identification and configuration screen page 2
• HPTCC failure is “economic” when DAC or BSV eliminated (because TBV is large bore)
• HPTCC failure is “no go” or “short time” when SAC with a functioning BSV
• Permits a 7B26 on a 737-700
• Permits the Pre-inspection of DMS through an EEC test
(before this SB, a fault was triggered when a particles was detected on ground with 7000 <N2<10000 rpm)
• For the start lever selection logic, (due to problem during starting)
• now, EEC uses 2 of the 4 inputs to determine the position of the start lever:
1 from Ch A, 1 from Ch B, voltage to Right igniter, voltage to left igniter
• A CDU screen is available to display start lever input and igniter voltage
• N2 difference fault is added in the short time dispatch
• N2 tone logic extend up to 41.000 ft
• Consequently, VSVs stay on transient schedule and min flight idle is 10.400 rpm
Soft 7B40 (7BK) benefit for SAC
Issue: 4/9/2011
23
7
•MSV failed open and closed position fault
•To avoid an ATO due to a wrong switch feedback
•Fan speed oscillation
•Steady state control logic has been changed so steady state operation can be
determined sooner
Soft 7B40 (7BK) intro consists in : For DAC
Issue: 4/9/2011
23
8
Staged
Unstaged
Staged
Staged
Unstaged
Unstaged
20 FN operation 10 FN operation
Issue: 4/9/2011
23
9
Total air temperature
Corrected static pressure
Total pressure
Calculated mach number
Greenwich mean time
Clock date
N1 target
Flight number
Bite data
Landing gear position
Start valve position
Engine run status of other engine
Databus status
Start switch position
Start lever position
Ignition switch position
Control mode switch position
Wing anti ice switch position
ACS pack switch position
Cowl thermal anti ice switch position
Isolation valve position
DIGITAL INPUT DATA FROM DEU TO THE EEC
Issue: 4/9/2011
24
0
Bite data
Engine start mode
Engine starting status
Ignition system status
Engine running status
Control mode switch position
Start lever position
Minimum idle
Idle selected
N1 speed data
N2 speed data
Overspeed governor status
Engine starter cutout
Exhaust gaz temperature data
Fuel flow data
Fuel filter status
Oil pressure and temperature data
Oil filter status
Thrust resolver angle data
Thrust reverser status
Thrust reverser interlock status
Engine thrust
Values from engine sensors
EEC software version
Engine serial number
Position of engine actuators
Fuel Air ratio in combustor
EEC channel in control
DIGITAL INPUT DATA FROM EEC TO THE DEU
Issue: 4/9/2011
24
1
Airplane on ground selection status
Engine running
Engine thrust rating and airplane model incompatible
Airplane model
Engine rating
Engine option
EEC alternator status
Engine position
Engine bleed load
Air data status from ADIRU
Internal EEC fault
DIGITAL INPUT DATA FROM EEC TO THE DEU
Issue: 4/9/2011
24
2
received by the EEC
Thrust lever resolver angle
Thrust reverser position
Engine position
Airplane model
Position of engine actuator
Control mode switch data
send to the AIRCRAFT
N1 speed
N2 speed
Oil quantity
HPSOV position command
Thrust reverser interlock solenoid command
ANALOG control data
Issue: 4/9/2011
24
3
Few examples of parameter range test limits
Input Minimum Maximum
FMV - 15 deg 111 deg
HPTC - 3.0% 105%
VBV - 5 deg 39 deg
VSV - 0.09 in 3.62 in
N1 0 rpm 6215 rpm
N2 0 rpm 17525 rpm
PS25 1.96 psia 50.3 psia
PS3 5.0 psia 550 psia
TATsel -60.0°C 90.0°C
WFM 0 pph 15080 pph
PEO -2.03 psi 101.5 psi
TEO -63.0°C 170°C
Issue: 4/9/2011
24
4
Dual Sensor
with model
PS3
N1
N2
T3
T25
FMV
VSV
VBV
Parameters
without model
Tc
TEO
Tecu
HPTC
TBV
PEO
LPTC
Issue: 4/9/2011
24
5
• BSV élimination (because flameout margin is sufficient w/o BSV)
• must be accompanied with TBV large bore
• can be verified on identification and configuration screen page 2
• HPTCC failure is “economic” when DAC or BSV eliminated (because TBV is large bore)
• HPTCC failure is “no go” or “short time” when SAC with a functioning BSV
• Permits a 7B26 on a 737-700
• Permits the Pre-inspection of DMS through an EEC test
(before this SB, a fault was triggered when a particles was detected on ground with 7000 <N2<10000 rpm)
• For the start lever selection logic, (due to problem during starting)
• now, EEC uses 2 of the 4 inputs to determine the position of the start lever:
1 from Ch A, 1 from Ch B, voltage to Right igniter, voltage to left igniter
• A CDU screen is available to display start lever input and igniter voltage
• N2 difference fault is added in the short time dispatch
• N2 tone logic extend up to 41.000 ft
• Consequently, VSVs stay on transient schedule and min flight idle is 10.400 rpm
Soft 7B40 (7BK) benefit for SAC
Issue: 4/9/2011
24
6
•MSV failed open and closed position fault
•To avoid an ATO due to a wrong switch feedback
•Fan speed oscillation
•Steady state control logic has been changed so steady state operation can be
determined sooner
Soft 7B40 (7BK) intro consists in : For DAC
Issue: 4/9/2011
24
7
Max Thrust rating
N1 trim level
0 1 2 3 4 5 6 7
- 0.4 % of N1
- 0.8 %
- 1.1 %
- 1.5 %
- 1.9 %
- 2.5 %
- 3.0 %
27300 lbs
Min margin
+ 1 %
N1 trim level
Issue: 4/9/2011
24
8
Max Thrust rating
N1 trim level
- 1.5 %
- 3.0 %
- 0.8 %
27300 lbs
Min margin
+ 1 %
2 4 7
876503 876602 876315
Before trim
N1 trim wash out if:
• Alt > 15.000ft or
• Mn > 0.4 or
• physical N1 speed approaches 0.46 % of N1 redline
N1 trim
Issue: 4/9/2011
24
9
Staged
Unstaged
Staged
Staged
Unstaged
Unstaged
20 FN operation 10 FN operation
Issue: 4/9/2011
25
0
T.A.T
Tamb
DeltaTemp from standard day
DTstd = Tamb - Tstd
M0
P.T P.0
T12 Channel A
T12 Channel B
TAT ADIRU 1
TAT ADIRU 2
PT ADIRU 1
PT ADIRU 2
P0 Channel A
P0 Channel B
PS ADIRU 1
PS ADIRU 2
Normal operation
To be valid, both PTADC must be available
and at least one pitot probe heater must be
active
TAT probe may
not be aspirated,
so EEC uses T12
on ground for
5mn after T/O
Temp standard =
f(Alt)
Issue: 4/9/2011
25
1
T.A.T
Tamb SynthetizedM0 Temp standard =
f(Alt)
P.T P.0
T12 Channel A
T12 Channel B
TAT ADIRU 1
TAT ADIRU 2
PT ADIRU 1
PT ADIRU 2
P0 Channel A
P0 Channel B
PS ADIRU 1
PS ADIRU 2
Soft alternate mode
DeltaTemp from
standard day is frozen
Issue: 4/9/2011
25
2
T.A.T
Tamb
DTstd = Corner point
M0
P.T P.0
T12 Channel A
T12 Channel B
TAT ADIRU 1
TAT ADIRU 2
PT ADIRU 1
PT ADIRU 2
P0 Channel A
P0 Channel B
PS ADIRU 1
PS ADIRU 2
Hard alternate mode - PT invalid
Default M0 Temp standard
= f(Alt)
Retour
présentation
Issue: 4/9/2011
25
3
Tstd (Standard Temperature)
= 288 - 6.5 * Alt
when ALT < 36090 ft
Altitude
Temp
-55 15
0
36090
Delta temp from Standard day
Issue: 4/9/2011
25
4
M0 =
PT
Po ( )0.286
- 1
0.2
To be valid, both PTADC must be available and at
least one pitot probe heater must be active
Issue: 4/9/2011
25
5
M0 =
TAT - Ts
0.2 Ts
TAT is Measured
Ts is the local static temp
So we need to know
the standard atmosphere
Synthetized
Mach Number
Issue: 4/9/2011
25
6
TAT
Ts
= 1 + 0.2 M²
Tamb = Ts = TAT (measured)
when:
•A/C on ground
•A/C speed = 0
Ts = Tamb =
When A/C speed # 0
TAT
1+0.2M²
Issue: 4/9/2011
25
7
Issue: 4/9/2011
25
8
Issue: 4/9/2011
25
9
73-x033n
Message Number format
n = Engine position:
• 0 = error
• 1 = eng 1
• 2 = eng 2
033 = Fault Code
Bite doc page number
x = EEC channel:
•1 = A
•2 = B
•3 = A and B
73 = ATA chapter :
•73 = Fuel
•75 = Air
•79 = Oil
•Etc,Etc
Issue: 4/9/2011
26
0
FLIGHT LEG STORAGE PROCESSING
GROUND -> FLIGHT >
FLIGHT -> GROUND >
EEC POWER UP >
FLIGHT IND = GROUND
ENG START >
FLIGHT IND = FLIGHT >
FLIGHT IND = GROUND >
(for at least 30 sec)
ENGINE SHUTDOWN >
EEC POWER OFF >
ENGOFF ENGON FLTCYC
N2 > 40%
GROUND RUN FAILURES
FLIGHT 0 FLIGHT 1
GROUND FLIGHT GROUND
Faults Not
Stored in
“NVM”
Faults Not
Stored in
“NVM”
(Increment Flight Leg)
Issue: 4/9/2011
26
1
BSV - FUNCTIONAL DESCRIPTION
• EEC controls BSV position based on Fuel Air Ratio
– It uses T3, PS3, FMV position, N2 speed, Air/Ground signals from DEU to find
the best Fuel/air ratio.
• BSV positions is: Open or Close
–When open, 20 fuel nozzles are fuel supplied (BSV inhibited)
• Instr note: better thermal distribution in the combustor at high Fuel Air Ratio (FAR)
• Always open for 55% > N2 speed < 80% , engine at steady state on ground or when
the EEC cannot read the BSV position (failsafe)
– when closed, 10 fuel nozzles are always fuel supplied
At low FAR, EEC energizes BSV solenoid in the HMU to close the BSV
• Reinforced spray pattern (Instr note: increase flame out margin)
• An override valve permits to open the BSV, if the valve is faulty commanded closed
• DEU energizes the engine “CONTROL LIGHT” on the aft P5 over head
panel and master caution lights:
– If the EEC finds a no dispatch condition, and when EEC sends signal of failure
to DEU:
• BSV failed in closed pos., Control current out of range, EEC in single channel operat.
73-11-00 THRUST CONTROL
BSV
Issue: 4/9/2011
26
2
Thust limiting logic
Inst. Note: Nice to know; not mandatory neither part of the course
76-00-00 FUEL CONTROL - COMP. LOCATION - LEFT SIDE
idle
Full thrust
10% 15 70 90
Rev thrust
60 Fully
deployed
Fully
stowed
“REV” message is amber
“REV” message
Interlock solenoid energises is green
Rev thrust is applied
Interlock set
40
Issue: 4/9/2011
26
3
CFM56-7 LINE & BASE COURSE OUTLINES
1. Maintenance Documents
2. Power Plant General (71)
3. Engine Exhaust (78)
4. Engine General (72)
5. Fuel and Control System (73) (SAC)
5. Fuel and Control System (DAC)
5. Engine Electrical Wiring Harnesses
6. Air System (75)
7. Ignition System (74)
8. Start System (80)
9. Oil System (79)
10. Engine Indicating System (77)
11. Engine Fault Isolation - CDU Messages
MAINTENANCE 71-00-00 DOCUMENTS - INTRODUCTION 怎么看不到呀！ 真心收藏，哈哈 谢谢楼主…………。 值得下载收藏学习 希望有用，好好学习学习 好好学习下！！~~~~~~~~ 好资料！好资料！好资料！好资料！ 谢谢楼主谢谢楼主谢谢楼主谢谢楼主谢谢楼主
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