AUXILIARY POWER UNIT
Table of Contents
Vol. 1
04--00--1
AUXILIARY POWER UNIT
Table of Contents
REV 56, Jan 31/03
CHAPTER 4 ---AUXILIARY POWER UNIT
Vol. 1
04--00--1
REV 56, Jan 31/03
CHAPTER 4 ---AUXILIARY POWER UNIT
Page
Page
04--00
04--00--1
TABLE OF CONTENTS
Table of Contents
04--00
04--00--1
INTRODUCTION
Introduction
04--10
04--10--1
INTRODUCTION
Introduction
04--10
04--10--1
POWER PLANT
APU Power Plant
Engine
Gearbox
04--20
04--20--1
04--20--1
04--20--1
POWER PLANT
APU Power Plant
Engine
Gearbox
SYSTEMS
Systems
Lubrication
Fuel
Ignition and Starting
Air Intake
04--30
04--30--1
04--30--1
04--30--1
04--30--1
04--30--1
SYSTEMS
Systems
Lubrication
Fuel
Ignition and Starting
Air Intake
04--40
04--40--1
04--40--1
04--40--2
04--40--9
04--40--10
CONTROL
Control
Starting
Stopping
Protective Shutdown
System Circuit Breakers
04--20
04--20--1
04--20--1
04--20--1
04--30
04--30--1
04--30--1
04--30--1
04--30--1
04--30--1
04--40
04--40--1
04--40--1
04--40--2
04--40--9
04--40--10
LIST OF ILLUSTRATIONS
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LIST OF ILLUSTRATIONS
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CONTROL
Control
Starting
Stopping
Protective Shutdown
System Circuit Breakers
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TABLE OF CONTENTS
Table of Contents
Auxiliary Power Unit Installation
Auxiliary Power Unit Pneumatic Flow
Auxiliary Power Unit Indication
04--10--2
04--10--3
04--10--4
SYSTEMS
Figure 04--30--1
Figure 04--30--2
Auxiliary Power Unit Controls and ECU Interface
Auxiliary Power Unit Door Position Chart
CONTROL
Figure 04--40--1
Figure 04--40--2
Start/Stop Run Controls
Fuel Synoptic Page
Flight Crew Operating Manual
CSP A--013
INTRODUCTION
Figure 04--10--1
Figure 04--10--2
Figure 04--10--3
Auxiliary Power Unit Installation
Auxiliary Power Unit Pneumatic Flow
Auxiliary Power Unit Indication
04--10--2
04--10--3
04--10--4
04--30--2
04--30--3
SYSTEMS
Figure 04--30--1
Figure 04--30--2
Auxiliary Power Unit Controls and ECU Interface
Auxiliary Power Unit Door Position Chart
04--30--2
04--30--3
04--40--3
04--40--4
CONTROL
Figure 04--40--1
Figure 04--40--2
Start/Stop Run Controls
Fuel Synoptic Page
04--40--3
04--40--4
Fo
INTRODUCTION
Figure 04--10--1
Figure 04--10--2
Figure 04--10--3
Flight Crew Operating Manual
CSP A--013
AUXILIARY POWER UNIT
Table of Contents
AUXILIARY POWER UNIT
Table of Contents
04--40--5
04--40--6
04--40--7
04--40--8
Figure 04--40--3
Figure 04--40--4
Figure 04--40--5
Figure 04--40--6
Vol. 1
04--00--2
REV 56, Jan 31/03
APU Door and Run Indication
APU EICAS Messages -- Primary Page
APU EICAS Messages -- Status
APU Start Sequence
04--40--5
04--40--6
04--40--7
04--40--8
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APU Door and Run Indication
APU EICAS Messages -- Primary Page
APU EICAS Messages -- Status
APU Start Sequence
04--00--2
REV 56, Jan 31/03
Fo
Figure 04--40--3
Figure 04--40--4
Figure 04--40--5
Figure 04--40--6
Vol. 1
Flight Crew Operating Manual
CSP A--013
Flight Crew Operating Manual
CSP A--013
AUXILIARY POWER UNIT
Introduction
04--10--1
AUXILIARY POWER UNIT
Introduction
REV 56, Jan 31/03
INTRODUCTION
1.
Vol. 1
04--10--1
REV 56, Jan 31/03
INTRODUCTION
The auxiliary power unit (APU) is installed within a fireproof titanium enclosure in the aft
equipment compartment. The APU is a fully automated gas turbine power plant which
drives an electrical generator. The generator is rated at 30 kVA and produces 115 VAC
electrical power for backup to the main engine generators (refer to Chapter 7). The APU
also supplies compressed air to the pneumatic system for main engine starting and
environmental control (refer to Chapter 19).
The maximum operating altitude of the APU is 37,000 feet. The maximum altitude for APU
starting is 30,000 feet. The maximum altitude for main engine starting using APU bleed air
is 13,000 feet. ECS operation using APU bleed air is 15,000 feet.
The maximum operating altitude of the APU is 37,000 feet. The maximum altitude for APU
starting is 30,000 feet. The maximum altitude for main engine starting using APU bleed air
is 13,000 feet. ECS operation using APU bleed air is 15,000 feet.
An Electronic Control Unit (ECU), located in the aft equipment compartment, controls the
APU through all phases of operation. The ECU monitors all sensors and switches, sets up
the appropriate fuel acceleration schedules and relays specific operating data to the engine
indication and crew alerting system (EICAS). The ECU is powered through selection of a
PWR/FUEL switchlight on the APU control panel in the flight compartment.
An Electronic Control Unit (ECU), located in the aft equipment compartment, controls the
APU through all phases of operation. The ECU monitors all sensors and switches, sets up
the appropriate fuel acceleration schedules and relays specific operating data to the engine
indication and crew alerting system (EICAS). The ECU is powered through selection of a
PWR/FUEL switchlight on the APU control panel in the flight compartment.
The APU intake door position is continuously shown on the EICAS status page. APU RPM
and exhaust gas temperature (EGT) indications are shown on the EICAS status page, only
when the APU PWR/FUEL switchlight on the APU control panel is selected.
The APU intake door position is continuously shown on the EICAS status page. APU RPM
and exhaust gas temperature (EGT) indications are shown on the EICAS status page, only
when the APU PWR/FUEL switchlight on the APU control panel is selected.
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The auxiliary power unit (APU) is installed within a fireproof titanium enclosure in the aft
equipment compartment. The APU is a fully automated gas turbine power plant which
drives an electrical generator. The generator is rated at 30 kVA and produces 115 VAC
electrical power for backup to the main engine generators (refer to Chapter 7). The APU
also supplies compressed air to the pneumatic system for main engine starting and
environmental control (refer to Chapter 19).
Fo
1.
Vol. 1
Flight Crew Operating Manual
CSP A--013
Flight Crew Operating Manual
CSP A--013
Vol. 1
AUXILIARY POWER UNIT
Introduction
04--10--2
Vol. 1
AUXILIARY POWER UNIT
Introduction
REV 56, Jan 31/03
APU INTAKE
BLEED AIR
DUCT
BLEED AIR
DUCT
APU ENCLOSURE
LOAD
CONTROL
VALVE
OIL
COOLER
EXHAUST
PIPE
ASSEMBLY
STARTER
STARTER
COOLING
AIR
EXHAUST
GENERATOR
OIL
MODULE
GENERATOR
FUEL
MODULE
OIL
COOLER
EXHAUST
PIPE
ASSEMBLY
COOLING
AIR
EXHAUST
OIL
MODULE
SERVICE
DOOR
ENGINE FIRE
EXTINGUISHER
COOLING
AIR INLET
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FUEL
MODULE
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APU ENCLOSURE
LOAD
CONTROL
VALVE
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APU INTAKE
04--10--2
REV 56, Jan 31/03
SERVICE
DOOR
ENGINE FIRE
EXTINGUISHER
SUPPORT
SKID
ECU
CUT--OFF
SWITCH
Auxiliary Power Unit Installation
Figure 04---10---1
Flight Crew Operating Manual
CSP A--013
COOLING
AIR INLET
SUPPORT
SKID
ECU
CUT--OFF
SWITCH
Auxiliary Power Unit Installation
Figure 04---10---1
Flight Crew Operating Manual
CSP A--013
Vol. 1
AUXILIARY POWER UNIT
Introduction
04--10--3
REV 56, Jan 31/03
45
45
40
40
35
35
REV 56, Jan 31/03
.85 M
30
.85 M
25
.80 M
25
.80 M
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20
15
15
10
10
335 Kt
5
0
100
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30
20
335 Kt
5
150
200
250
300
0
100
350
330 Kt
LEFT PACK
SHUTOFF
VALVE
LEFT
ENGINE
LEFT 10TH
STAGE BLEED
SHUTOFF
VALVE
APU
RIGHT PACK
SHUTOFF
VALVE
ISOLATION
VALVE
CHECK
VALVE
AIR
TURBINE
STARTER
RIGHT 10TH
STAGE BLEED
SHUTOFF
VALVE
LOAD
CONTROL
APU VALVE
CHECK
VALVE
RIGHT
ENGINE
150
200
250
300
350
AIR
TURBINE
STARTER
LEFT
ENGINE
CHECK
VALVE
330 Kt
STARTER
CONTROL
VALVE
LEFT PACK
SHUTOFF
VALVE
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STARTER
CONTROL
VALVE
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AIR
TURBINE
STARTER
CHECK
VALVE
04--10--3
Vol. 1
AUXILIARY POWER UNIT
Introduction
LEFT 10TH
STAGE BLEED
SHUTOFF
VALVE
APU
RIGHT PACK
SHUTOFF
VALVE
ISOLATION
VALVE
CHECK
VALVE
AIR
TURBINE
STARTER
RIGHT 10TH
STAGE BLEED
SHUTOFF
VALVE
LOAD
CONTROL
APU VALVE
Auxiliary Power Unit Pneumatic Flow
Figure 04---10---2
Auxiliary Power Unit Pneumatic Flow
Figure 04---10---2
Flight Crew Operating Manual
CSP A--013
Flight Crew Operating Manual
CSP A--013
CHECK
VALVE
RIGHT
ENGINE
Vol. 1
AUXILIARY POWER UNIT
Introduction
04--10--4
<0006>
<0039>
04--10--4
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AUXILIARY POWER UNIT
Introduction
REV 56, Jan 31/03
REV 56, Jan 31/03
<0006>
<0039>
CAUTION
MESSAGES
APU START/STOP
SWITCH/LIGHT
FUEL SHUTOFF VALVE
SWITCH/LIGHT
APU Control Panel
Overhead Panel
APU Control Panel
Overhead Panel
Primary Page
APU EGT Indicator
and Readout
Indicates exhaust gas
temperature in degrees
celcius.
<0039>
<0039>
APU Inlet Door
Status Indicator
Indicates DOOR OPEN
or DOOR CLOSED or
DOOR MID Position.
Primary Page
APU EGT Indicator
and Readout
Indicates exhaust gas
temperature in degrees
celcius.
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APU RPM Indicator
and Readout
Indicates percent of
APU rpm.
APU START/STOP
SWITCH/LIGHT
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FUEL SHUTOFF VALVE
SWITCH/LIGHT
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CAUTION
MESSAGES
APU RPM Indicator
and Readout
Indicates percent of
APU rpm.
APU Inlet Door
Status Indicator
Indicates DOOR OPEN
or DOOR CLOSED or
DOOR MID Position.
Status Page
Status Page
Auxiliary Power Unit Indication <MST>
Figure 04---10---3
Auxiliary Power Unit Indication <MST>
Figure 04---10---3
Flight Crew Operating Manual
CSP A--013
Flight Crew Operating Manual
CSP A--013
<0039>
<0039>
AUXILIARY POWER UNIT
Power Plant
04--20--1
AUXILIARY POWER UNIT
Power Plant
REV 56, Jan 31/03
APU POWER PLANT
1.
Vol. 1
REV 56, Jan 31/03
The APU power plant consists of a gas turbine engine and a gearbox.
The APU power plant consists of a gas turbine engine and a gearbox.
A.
A.
Gearbox
B.
The gearbox reduces the turbine shaft rpm to a speed suitable to operate the gearbox
mounted accessories. Accessories include the lubrication module, fuel control unit,
electric starter and generator. The gearbox has an integral oil sump. The oil level can
be checked using a sight glass on the oil filler assembly.
Gearbox
The gearbox reduces the turbine shaft rpm to a speed suitable to operate the gearbox
mounted accessories. Accessories include the lubrication module, fuel control unit,
electric starter and generator. The gearbox has an integral oil sump. The oil level can
be checked using a sight glass on the oil filler assembly.
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B.
The engine is a single-shaft, constant speed design, consisting of a compressor, a
combustor and a two-stage turbine. The compressor draws large volumes of air in
through the inlet door on top of the aft fuselage then delivers it under pressure to the
combustor. Fuel from both wing tanks is added to the high pressure air and ignited,
increasing the energy of the airflow. The high velocity, high temperature gasses are
delivered to the turbine section. The turbine converts the high velocity gasses into
mechanical energy to drive the compressor and gearbox. The exhaust gases are
ducted overboard through the exhaust pipe on the right aft fuselage.
ly
The engine is a single-shaft, constant speed design, consisting of a compressor, a
combustor and a two-stage turbine. The compressor draws large volumes of air in
through the inlet door on top of the aft fuselage then delivers it under pressure to the
combustor. Fuel from both wing tanks is added to the high pressure air and ignited,
increasing the energy of the airflow. The high velocity, high temperature gasses are
delivered to the turbine section. The turbine converts the high velocity gasses into
mechanical energy to drive the compressor and gearbox. The exhaust gases are
ducted overboard through the exhaust pipe on the right aft fuselage.
Engine
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Engine
Flight Crew Operating Manual
CSP A--013
04--20--1
APU POWER PLANT
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Vol. 1
04--20--2
AUXILIARY POWER UNIT
Power Plant
REV 56, Jan 31/03
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04--20--2
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Power Plant
Flight Crew Operating Manual
CSP A--013
Flight Crew Operating Manual
CSP A--013
AUXILIARY POWER UNIT
Systems
04--30--1
AUXILIARY POWER UNIT
Systems
REV 56, Jan 31/03
SYSTEMS
1.
Vol. 1
04--30--1
REV 56, Jan 31/03
SYSTEMS
The APU consists of a lubrication system, fuel system, ignition and starting systems, and an
air intake and exhaust.
The APU consists of a lubrication system, fuel system, ignition and starting systems, and an
air intake and exhaust.
A.
A.
B.
Fuel
The lubricating system consists of a mechanically driven lubrication module, oil filter, oil
cooler, low oil pressure switch, and an oil temperature sensor. The lube module
provides pressurized oil to the power plant, gearbox and generator for lubrication and
heat removal.
B.
Fuel is supplied to the APU fuel control unit from the left and right wing tanks by the
XFLOW/APU pump (refer to Chapter 13). The fuel shutoff valve is opened by the ECU
at 10% speed. The fuel control unit starts, stops and modulates the flow of fuel to the
APU in response to commands from the ECU.
C.
Ignition and Starting
C.
The ignition and starter systems are controlled by the ECU. The ECU commands the
DC starter motor to rotate the power plant. The starter accelerates the power plant to a
specific speed where the ECU introduces fuel to the combustor. The ignition system is
provided to ignite the fuel/air mixture in the combustor which further accelerates the
power plant. As the APU accelerates towards the onspeed condition, the starter is
disengaged. When the APU reaches normal operating speed the ignition is turned off.
At this point the engine becomes self sufficient.
D.
The air inlet door is located in the upper rear fuselage. An actuator, controlled by the
ECU positions the door. When open, the door provides ram air for APU operation and
the oil cooling. On the ground, the air inlet door has only two positions, open and
closed (0 and 42_). In flight, during APU start above 13,000 feet, the ECU limits the
door position in response to APU engine rpm and aircraft speed. This prevents
excessive amounts of ram air which could cause the APU to flameout. For APU start
below 13,000 feet, the door is fully open.
When the APU is not operating, the door remains closed to prevent windmilling of the
compressor. The inlet door also serves as a barrier in the event of fire.
Flight Crew Operating Manual
CSP A--013
Ignition and Starting
Air Intake
The air inlet door is located in the upper rear fuselage. An actuator, controlled by the
ECU positions the door. When open, the door provides ram air for APU operation and
the oil cooling. On the ground, the air inlet door has only two positions, open and
closed (0 and 42_). In flight, during APU start above 13,000 feet, the ECU limits the
door position in response to APU engine rpm and aircraft speed. This prevents
excessive amounts of ram air which could cause the APU to flameout. For APU start
below 13,000 feet, the door is fully open.
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Air Intake
Fuel
Fuel is supplied to the APU fuel control unit from the left and right wing tanks by the
XFLOW/APU pump (refer to Chapter 13). The fuel shutoff valve is opened by the ECU
at 10% speed. The fuel control unit starts, stops and modulates the flow of fuel to the
APU in response to commands from the ECU.
The ignition and starter systems are controlled by the ECU. The ECU commands the
DC starter motor to rotate the power plant. The starter accelerates the power plant to a
specific speed where the ECU introduces fuel to the combustor. The ignition system is
provided to ignite the fuel/air mixture in the combustor which further accelerates the
power plant. As the APU accelerates towards the onspeed condition, the starter is
disengaged. When the APU reaches normal operating speed the ignition is turned off.
At this point the engine becomes self sufficient.
D.
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The lubricating system consists of a mechanically driven lubrication module, oil filter, oil
cooler, low oil pressure switch, and an oil temperature sensor. The lube module
provides pressurized oil to the power plant, gearbox and generator for lubrication and
heat removal.
Lubrication
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Lubrication
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Vol. 1
When the APU is not operating, the door remains closed to prevent windmilling of the
compressor. The inlet door also serves as a barrier in the event of fire.
Flight Crew Operating Manual
CSP A--013
PWR
FUEL
APU
Flight Crew Operating Manual
CSP A--013
R
ENG
Auxiliary Power Unit Controls and ECU Interface
Figure 04---30---1
APU
Flight Crew Operating Manual
CSP A--013
ECU
Auxiliary Power Unit Controls and ECU Interface
Figure 04---30---1
OIL/GEN. FILTERS DELTA P
GND
APU COMPARTMENT
SHUTDOWN SWITCH
P
EXHAUST GAS TEMPERATURE (EGT)
IGNITION ON/OFF
IGNITION BUILT--IN TEST
FUEL
SOV
GEN
STARTER
GEARBOX
SPEED
SENSOR
P2 SENSOR
T2 SENSOR
OIL TEMPERATURE SENSOR
FUEL CONTROL OIL
UNIT
PUMP
AC TO AIRCRAFT
GCU
TO EDUCTOR
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APU
IGNITION
EXCITER
FUEL
NOZZLE
ASSEMBLY
EGT SENSOR
LOAD CONTROL
VALVE (LCV)
FUEL
NOZZLE
ASSEMBLY
EGT SENSOR
Vol. 1
OIL TEMPERATURE
FUEL SOLENOID VALVE
TORQUE MOTOR MET. VALVE
DEPRIME
LOP SWITCH
APU STARTER -- CONTACTOR
UNIT
AIRCRAFT
BATTERY
AIR
ADC
IOC
MDC
DC POWER 28 VOLTS
APU GENERATOR READY TO LOAD
STARTER VOLTS
GEN. LOAD LEVEL
GEN. OVERLOAD
SPEED
LCV OPEN
INLET TEMPERATURE (T2)
INLET PRESSURE (P2)
DCU
AIR
INLET
DOOR
BLEED FLOW
IGNITION
EXCITER
AUXILIARY POWER UNIT
Systems
EXTERNAL SERVICES
PANEL
PSEU
SPEED
AIR/OIL COOLER
INLET
AIR
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INLET DOOR POSITION
INLET DOOR ACTUATOR
LCV CLOSE
TO ECU
OIL TEMPERATURE SENSOR
APU
LOAD CONTROL
VALVE (LCV)
04--30--2
EGT
R
ENG
RUN
POWER
LCV POSITION (RVDT)
LCV POSITION COMMAND (TORQUE MOTOR)
re
P
EXHAUST GAS TEMPERATURE (EGT)
IGNITION ON/OFF
IGNITION BUILT--IN TEST
OIL TEMPERATURE
FUEL SOLENOID VALVE
FUEL
SOV
GEN
STARTER
FUEL CONTROL OIL
UNIT
PUMP
AC TO AIRCRAFT
SPEED
SENSOR
P2 SENSOR
INLET
DOOR
REV 56, Jan 31/03
EICAS
STAT PAGE
L
ENG
BLEED SOURCE
BOTH ENG
START
START/
STOP
APU COMPARTMENT
SHUTDOWN SWITCH
PWR
FUEL
Fo
OIL/GEN. FILTERS DELTA P
GND
TORQUE MOTOR MET. VALVE
DEPRIME
LOP SWITCH
APU STARTER -- CONTACTOR
UNIT
AIRCRAFT
BATTERY
GCU
AIR
T2 SENSOR
GEARBOX
AIR/OIL COOLER
TO EDUCTOR
INLET
AIR
BLEED FLOW
Vol. 1
APU
ECU
DC POWER 28 VOLTS
APU GENERATOR READY TO LOAD
STARTER VOLTS
GEN. LOAD LEVEL
AIR
ADC
IOC
MDC
DCU
SPEED
LCV OPEN
GEN. OVERLOAD
INLET PRESSURE (P2)
INLET TEMPERATURE (T2)
INLET DOOR ACTUATOR
INLET DOOR POSITION
LCV POSITION (RVDT)
LCV POSITION COMMAND (TORQUE MOTOR)
LCV CLOSE
TO ECU
POWER
RUN
START
START/
STOP
EXTERNAL SERVICES
PANEL
PSEU
SPEED
EGT
EICAS
STAT PAGE
L
ENG
BLEED SOURCE
BOTH ENG
APU
AUXILIARY POWER UNIT
Systems
REV 56, Jan 31/03
04--30--2
Vol. 1
AUXILIARY POWER UNIT
Systems
04--30--3
Vol. 1
AUXILIARY POWER UNIT
Systems
REV 56, Jan 31/03
40K
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REV 56, Jan 31/03
04--30--3
40K
OUTSIDE OF SHADED AREA
DOOR IS POSITIONED TO 28
30K
PRESSURE
ALTITUDE
-- MID
20K
PRESSURE
ALTITUDE
DOOR POSITIONED
TO 42 -- OPEN
500 ft set point
change area
OUTSIDE OF SHADED AREA
DOOR IS POSITIONED TO 28
30K
DOOR POSITIONED
TO 42 -- OPEN
500 ft set point
change area
20K
6 knots set point
change area
13K
-- MID
6 knots set point
change area
13K
10K
10K
0
100
210
200
0
260
400
0
100
210
200
260
TRUE AIRSPEED (TAS)
Fo
TRUE AIRSPEED (TAS)
300
re
0
Auxiliary Power Unit Door Position Chart
Figure 04---30---2
Flight Crew Operating Manual
CSP A--013
Auxiliary Power Unit Door Position Chart
Figure 04---30---2
Flight Crew Operating Manual
CSP A--013
300
400
Vol. 1
04--30--4
AUXILIARY POWER UNIT
Systems
REV 56, Jan 31/03
Vol. 1
04--30--4
REV 56, Jan 31/03
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Systems
Flight Crew Operating Manual
CSP A--013
Flight Crew Operating Manual
CSP A--013
AUXILIARY POWER UNIT
Control
04--40--1
AUXILIARY POWER UNIT
Control
REV 58, Oct 31/05
CONTROL
1.
Vol. 1
04--40--1
REV 58, Oct 31/05
CONTROL
The APU electronic control unit (ECU) provides full automatic control of APU starting,
stopping, and protects the APU during all modes of operation. The control system ensures
that priority is given to electrical loads by reducing bleed airflow.
The APU electronic control unit (ECU) provides full automatic control of APU starting,
stopping, and protects the APU during all modes of operation. The control system ensures
that priority is given to electrical loads by reducing bleed airflow.
A.
A.
Starting
Starting
When the PWR FUEL switchlight, on the APU panel, is selected:
S The ECU is powered
S The ECU is powered
S The air inlet door opens (position is displayed on the EICAS status page)
S The air inlet door opens (position is displayed on the EICAS status page)
S The APU fuel feed shutoff valve opens
S The APU fuel feed shutoff valve opens
S The APU RPM and EGT gauges are displayed on the EICAS status page
S The APU RPM and EGT gauges are displayed on the EICAS status page
S The fuel pump comes on.
S The fuel pump comes on.
When the START/STOP switchlight, on the APU control panel, is selected:
When the START/STOP switchlight, on the APU control panel, is selected:
S The ignition is activated
S The ignition is activated
S The starter motor is energized
S The starter motor is energized
S The FCU fuel solenoid shutoff valve opens
S The FCU fuel solenoid shutoff valve opens
S The START legend on the APU panel comes on
S The START legend on the APU panel comes on
S The APU START status message is displayed.
S The APU START status message is displayed.
The starter motor is deactivated at 50% rpm and the START legend goes out. When
the APU reaches 99% rpm, ignition is turned off and two seconds later the AVAIL
legend, in the START/STOP switchlight, illuminates to notify the crew that the APU is
ready to supply electrical power and bleed air.
The starter motor is deactivated at 50% rpm and the START legend goes out. When
the APU reaches 99% rpm, ignition is turned off and two seconds later the AVAIL
legend, in the START/STOP switchlight, illuminates to notify the crew that the APU is
ready to supply electrical power and bleed air.
APU Starter Limits
SOURCE
Battery
External DC Power
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(1)
(1)
START # and TIME ON
1 30 seconds
2 30 seconds
3 30 seconds
4 30 seconds
1 15 seconds
2 15 seconds
3 15 seconds
4 15 seconds
Flight Crew Operating Manual
CSP A--013
COOLING TIME
No cooling required
20 minutes
No cooling required
40 minutes
No cooling required
20 minutes
No cooling required
40 minutes
ly
When the PWR FUEL switchlight, on the APU panel, is selected:
Fo
1.
Vol. 1
APU Starter Limits
SOURCE
Battery
External DC Power
START # and TIME ON
1 30 seconds
2 30 seconds
3 30 seconds
4 30 seconds
1 15 seconds
2 15 seconds
3 15 seconds
4 15 seconds
Flight Crew Operating Manual
CSP A--013
COOLING TIME
No cooling required
20 minutes
No cooling required
40 minutes
No cooling required
20 minutes
No cooling required
40 minutes
Vol. 1
04--40--2
AUXILIARY POWER UNIT
Control
REV 56, Jan 31/03
NOTE
It is recommended that a 2 minute delay be observed
between start attempts to allow for cooling of the APU
start contactor and for fuel drainage.
Effectivity:
Effectivity:
S Airplanes 7003 to 7100 not incorporating Service Bulletin 601R--28--008
S Airplanes 7003 to 7100 not incorporating Service Bulletin 601R--28--008
NOTE
During normal operations, a nuisance XFLOW/APU
PUMP caution message may come on. When this
occurs, selecting the APU PWR/FUEL switchlight to
on then off will usually clear the message. If the
message clears, there is no operational restrictions
and the anomaly should be disregarded.
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NOTE
Stopping
04--40--2
REV 56, Jan 31/03
NOTE
It is recommended that a 2 minute delay be observed
between start attempts to allow for cooling of the APU
start contactor and for fuel drainage.
During normal operations, a nuisance XFLOW/APU
PUMP caution message may come on. When this
occurs, selecting the APU PWR/FUEL switchlight to
on then off will usually clear the message. If the
message clears, there is no operational restrictions
and the anomaly should be disregarded.
B.
Stopping
To shutdown the APU, the crew deselects the START/STOP switchlight on the APU
panel. The APU will automatically shed its loading and shutdown. The PWR/FUEL
switch is deselected to close the fuel shutoff valve and to remove primary electrical
power to the ECU.
In the event of an emergency, the flight crew can press the APU FIRE PUSH switchlight
on the glareshield. On the ground, the APU can be shut down by pushing an APU
emergency stop button located in the aft equipment compartment or by selecting the
APU shut--off (cover--guarded) switch on the external services panel on the RH forward
fuselage. Either selection sends a signal to the ECU to carry out an immediate
shutdown.
In the event of an emergency, the flight crew can press the APU FIRE PUSH switchlight
on the glareshield. On the ground, the APU can be shut down by pushing an APU
emergency stop button located in the aft equipment compartment or by selecting the
APU shut--off (cover--guarded) switch on the external services panel on the RH forward
fuselage. Either selection sends a signal to the ECU to carry out an immediate
shutdown.
NOTE
If overspeed or overtemperature occurs during flight,
do not restart the APU.
Flight Crew Operating Manual
CSP A--013
re
To shutdown the APU, the crew deselects the START/STOP switchlight on the APU
panel. The APU will automatically shed its loading and shutdown. The PWR/FUEL
switch is deselected to close the fuel shutoff valve and to remove primary electrical
power to the ECU.
Fo
B.
Vol. 1
ly
AUXILIARY POWER UNIT
Control
NOTE
If overspeed or overtemperature occurs during flight,
do not restart the APU.
Flight Crew Operating Manual
CSP A--013
Vol. 1
04--40--3
REV 58, Oct 31/05
When pressed out:
FCU solenoid shut--off
valve closes.
APU shuts down,
and
AVAIL light goes out.
APU Control Panel
Overhead Panel
Vol. 1
REV 58, Oct 31/05
APU START/STOP
Switch/Light
When pressed in,
starter motor is
energized and START
light (amber) comes on.
At 50% rpm, START
light goes out.
At 95% rpm, and 4
seconds later, AVAIL
light (green) comes on.
PWR FUEL Switch/Light
When pressed in, crossflow/APU pump is
energized, APU IN BITE, APU gauges energized,
door scheduled to open and APU fuel feed shut--off
valve opens.
PUMP FAIL light comes on to indicate that
crossflow/APU pump has failed.
SOV FAIL light comes on to indicate that the
APU fuel feed SOV has failed.
When pressed out:
FCU solenoid shut--off
valve closes.
APU shuts down,
and
AVAIL light goes out.
APU Control Panel
Overhead Panel
APU SHUT--OFF Switch
Used by maintenance personnel
to shut down the APU during
ground servicing.
APU SHUT--OFF Switch
Used by maintenance personnel
to shut down the APU during
ground servicing.
External Service Panel
Right Forward Fuselage
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External Service Panel
Right Forward Fuselage
APU EMER STOP Switch
Used by maintenance personnel
to shut down the APU during
ground servicing.
Fo
APU EMER STOP Switch
Used by maintenance personnel
to shut down the APU during
ground servicing.
AFT Equipment Bay
(Below APU)
Start/Stop Run Controls
Figure 04--40--1
Flight Crew Operating Manual
CSP A--013
04--40--3
ly
APU START/STOP
Switch/Light
When pressed in,
starter motor is
energized and START
light (amber) comes on.
At 50% rpm, START
light goes out.
At 95% rpm, and 4
seconds later, AVAIL
light (green) comes on.
PWR FUEL Switch/Light
When pressed in, crossflow/APU pump is
energized, APU IN BITE, APU gauges energized,
door scheduled to open and APU fuel feed shut--off
valve opens.
PUMP FAIL light comes on to indicate that
crossflow/APU pump has failed.
SOV FAIL light comes on to indicate that the
APU fuel feed SOV has failed.
AUXILIARY POWER UNIT
Control
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AUXILIARY POWER UNIT
Control
AFT Equipment Bay
(Below APU)
Start/Stop Run Controls
Figure 04--40--1
Flight Crew Operating Manual
CSP A--013
Vol. 1
04--40--4
AUXILIARY POWER UNIT
Control
REV 56, Jan 31/03
Vol. 1
04--40--4
REV 56, Jan 31/03
or
or
or
or
Fuel Synoptic Page
Fo
re
Fuel Synoptic Page
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AUXILIARY POWER UNIT
Control
Fuel Synoptic Page <MST>
Figure 04---40---2
Flight Crew Operating Manual
CSP A--013
Fuel Synoptic Page <MST>
Figure 04---40---2
Flight Crew Operating Manual
CSP A--013
AUXILIARY POWER UNIT
Control
Vol. 1
04--40--5
AUXILIARY POWER UNIT
Control
REV 56, Jan 31/03
Vol. 1
04--40--5
REV 56, Jan 31/03
<0039>
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<0039>
<0039>
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<0039>
Status Page
Fo
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Status Page
The APU gauges come
on when the electronic
control unit is powered
(APU PWR FUEL
switch/light pressed in).
With the ECU
powered, gauge
information is
maintained during
shutdown.
The APU gauges go
off when the electronic
control unit is not
powered (APU PWR
FUEL switch/light
pressed out).
APU Door and Run Indication <MST>
Figure 04---40---3
Flight Crew Operating Manual
CSP A--013
NOTE
The gauges will remain in
view for approximately
60 seconds, after PWR FUEL
switch/light pressed out.
The APU gauges come
on when the electronic
control unit is powered
(APU PWR FUEL
switch/light pressed in).
With the ECU
powered, gauge
information is
maintained during
shutdown.
The APU gauges go
off when the electronic
control unit is not
powered (APU PWR
FUEL switch/light
pressed out).
APU Door and Run Indication <MST>
Figure 04---40---3
Flight Crew Operating Manual
CSP A--013
NOTE
The gauges will remain in
view for approximately
60 seconds, after PWR FUEL
switch/light pressed out.
<0006>
APU OVERSPEED warning (red)
APU is running greater than 107 %
rpm. APU shuts down automatically.
APU
AUXILIARY POWER UNIT
Control
APU
APU OIL PRESS caution (amber)
APU has low oil pressure. APU shuts down
automatically. (On ground only).
APU OIL TEMP caution (amber)
APU has high oil temperature (325 C). APU
shuts down automatically. (On ground only).
APU FAULT caution (amber)
Loss of APU control circuits (microprocessor,
thermocouple or speed signal). APU shuts down
automatically.
APU SOV FAIL caution (amber)
APU Fuel Feed SOV not in a confirmed position
(either open or closed).
APU SOV OPEN caution (amber)
APU Fuel Feed SOV is open 10 seconds after an
APU fire condition. APU FUEL SOV light, on APU
panel, comes on (amber).
APU LCV FAIL caution (amber)
Load control valve has failed (either open or closed).
APU BLEED ON caution (amber)
Load control valve is open and barometric altitude
is greater than 15,000 feet.
X--FLOW/APU PUMP caution (amber)
Comes on to indicate that X--flow/APU pump has
failed (low pressure). Accompanied by XFER/APU
PUMP switch/light indicating FAIL.
APU OVERSPEED warning (red)
APU is running greater than 107 %
rpm. APU shuts down automatically.
APU
Flight Crew Operating Manual
CSP A--013
APU
APU OIL PRESS caution (amber)
APU has low oil pressure. APU shuts down
automatically. (On ground only).
APU OIL TEMP caution (amber)
APU has high oil temperature (325 C). APU
shuts down automatically. (On ground only).
<0039>
<0006>
APU FAULT caution (amber)
Loss of APU control circuits (microprocessor,
thermocouple or speed signal). APU shuts down
automatically.
APU SOV FAIL caution (amber)
APU Fuel Feed SOV not in a confirmed position
(either open or closed).
APU SOV OPEN caution (amber)
APU Fuel Feed SOV is open 10 seconds after an
APU fire condition. APU FUEL SOV light, on APU
panel, comes on (amber).
APU LCV FAIL caution (amber)
Load control valve has failed (either open or closed).
APU BLEED ON caution (amber)
Load control valve is open and barometric altitude
is greater than 15,000 feet.
X--FLOW/APU PUMP caution (amber)
Comes on to indicate that X--flow/APU pump has
failed (low pressure). Accompanied by XFER/APU
PUMP switch/light indicating FAIL.
Primary Page
APU EICAS Messages --- Primary Page <MST>
Figure 04---40---4
04--40--6
REV 58, Oct 31/05
re
Primary Page
APU OVERTEMP warning (red)
EGT is greater than 743 C with
APU RPM greater than 87 % or
greater than 974 C at all times.
APU shuts down automatically
(on ground).
Vol. 1
Fo
<0039>
04--40--6
REV 58, Oct 31/05
ly
APU OVERTEMP warning (red)
EGT is greater than 743 C with
APU RPM greater than 87 % or
greater than 974 C at all times.
APU shuts down automatically
(on ground).
Vol. 1
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AUXILIARY POWER UNIT
Control
APU EICAS Messages --- Primary Page <MST>
Figure 04---40---4
Flight Crew Operating Manual
CSP A--013
04--40--7
REV 56, Jan 31/03
APU SOV CLSD advisory (green)
APU fuel feed SOV is closed during
an APU fire condition.
APU IN BITE status (white)
Electronic control unit is running
diagnostics (prior to start), for
approximately 5 seconds.
APU IN BITE status (white)
Electronic control unit is running
diagnostics (prior to start), for
approximately 5 seconds.
<0039>
APU ECU FAIL status (white)
Electronic control unit has failed.
APU fuel feed SOV is confirmed
open.
<0039>
APU START status (white)
APU start in progress.
APU ECU FAIL status (white)
Electronic control unit has failed.
APU fuel feed SOV is confirmed
open.
APU LCV OPEN status (white)
APU load control valve is open.
10th stage, APU LCV OPEN
switch/light comes on.
APU LCV OPEN status (white)
APU load control valve is open.
10th stage, APU LCV OPEN
switch/light comes on.
APU SOV OPEN status (white)
APU fuel feed SOV is open with the
APU not ready and no APU fire
detected.
APU SOV OPEN status (white)
APU fuel feed SOV is open with the
APU not ready and no APU fire
detected.
Status Page
Fo
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Status Page
APU EICAS Messages --- Status <MST>
Figure 04---40---5
Flight Crew Operating Manual
CSP A--013
04--40--7
REV 56, Jan 31/03
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APU SOV CLSD advisory (green)
APU fuel feed SOV is closed during
an APU fire condition.
APU START status (white)
APU start in progress.
Vol. 1
AUXILIARY POWER UNIT
Control
ly
Vol. 1
AUXILIARY POWER UNIT
Control
APU EICAS Messages --- Status <MST>
Figure 04---40---5
Flight Crew Operating Manual
CSP A--013
<0039>
<0039>
APU Start Sequence <MST>
Figure 04---40---6
Flight Crew Operating Manual
CSP A--013
<0039>
<0039>
STARTER
CUTOUT
ly
Vol. 1
APU Start Sequence <MST>
Figure 04---40---6
Flight Crew Operating Manual
CSP A--013
LIGHT
OFF
FUEL SOLENOID
ENERGIZED
IGNITION ON
<0039>
AUXILIARY POWER UNIT
Control
BATTERY
PRESS
START/STOP
SW/LT
<0039>
04--40--8
PRESS
PWR FUEL
SW/LT
STARTER
CUTOUT
REV 56, Jan 31/03
ECU POWER--UP
DOOR TO
FULL OPEN
EICAS SECONDARY DISPLAY
LIGHT
OFF
FUEL SOLENOID
ENERGIZED
IGNITION ON
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Fo
PRESS
START/STOP
SW/LT
<0039>
<0039>
Vol. 1
SWITCH / LIGHT SELECTED
BATTERY
PRESS
PWR FUEL
SW/LT
<0039>
<0039>
ECU POWER--UP
DOOR TO
FULL OPEN
EICAS SECONDARY DISPLAY
SWITCH / LIGHT SELECTED
AUXILIARY POWER UNIT
Control
REV 56, Jan 31/03
04--40--8
AUXILIARY POWER UNIT
Control
04--40--9
AUXILIARY POWER UNIT
Control
REV 56, Jan 31/03
Protective Shutdown
C.
Vol. 1
04--40--9
REV 56, Jan 31/03
Protective Shutdown
The ECU will shut down the APU (on the ground) if any of the following faults occur:
The ECU will shut down the APU (on the ground) if any of the following faults occur:
S Overtemperature -- APU EGT exceeded schedule limits
S Overtemperature -- APU EGT exceeded schedule limits
S Low oil pressure (LOP) -- Low oil pressure exists for 15 seconds with the APU
S Low oil pressure (LOP) -- Low oil pressure exists for 15 seconds with the APU
S High oil temperature -- Oil temperature exceeded 325_C (617_F) with the APU
S High oil temperature -- Oil temperature exceeded 325_C (617_F) with the APU
S Overspeed -- APU speed exceeded 107 percent
S Overspeed -- APU speed exceeded 107 percent
S DC power loss -- Battery power lost
S DC power loss -- Battery power lost
S Loss of EGT signal -- EGT sensor failure
S Loss of EGT signal -- EGT sensor failure
S Loss of speed signal -- Speed sensor failure
S Loss of speed signal -- Speed sensor failure
S Overcurrent -- Fuel torque motor failure
S Overcurrent -- Fuel torque motor failure
S Door position -- Door not in commanded position
S Door position -- Door not in commanded position
S ECU failure -- Internal ECU failure
S ECU failure -- Internal ECU failure
S Slow start -- Starter time period exceeded
S Slow start -- Starter time period exceeded
S Emergency fire shutdown -- APU FIRE PUSH or one the two external stop switches
S Emergency fire shutdown -- APU FIRE PUSH or one the two external stop switches
S Starter relay -- No rotation.
S Starter relay -- No rotation.
All the above protective shutdowns are inhibited in flight mode by a weight--off--wheels
signal from the PSEU, except for the following 5 failures:
All the above protective shutdowns are inhibited in flight mode by a weight--off--wheels
signal from the PSEU, except for the following 5 failures:
have been activated
S Overspeed
ly
operating
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operating
operating
have been activated
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operating
S Overspeed
Fo
C.
Vol. 1
S DC power loss
S DC power loss
S ECU failure
S ECU failure
S Loss of speed signal
S Loss of speed signal
S Emergency fire shutdown.
S Emergency fire shutdown.
Flight Crew Operating Manual
CSP A--013
Flight Crew Operating Manual
CSP A--013
APU Controls
Auxiliary
Power Unit
APU
Electronic
Control Unit
Battery
Charging
Fire
Extinguishing
CB NAME
BUS BAR
CB
CB
PANEL LOCATION
APU BAT
CONT
APU BAT DIR
APU ACT
MAIN BAT
DIR
APU ECU
DC BAT
1
N12
APU
CHARGER
AC UTIL 2
2
E5
DC EMERG
APU FIRE EXT
BUS
NOTES
SYSTEM
SUB--SYSTEM
B2
5
APU Controls
A3
1
R5--6
Auxiliary
Power Unit
APU
Electronic
Control Unit
CB NAME
BUS BAR
APU BAT
CONT
APU BAT DIR
APU ACT
MAIN BAT
DIR
APU ECU
DC BAT
CB
CB
PANEL LOCATION
Battery
Charging
Fire
Extinguishing
APU
CHARGER
AC UTIL 2
DC EMERG
APU FIRE EXT
BUS
Flight Crew Operating Manual
CSP A--013
Flight Crew Operating Manual
CSP A--013
NOTES
B2
5
A3
1
N12
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SUB--SYSTEM
System Circuit Breakers
re
SYSTEM
D.
REV 56, Jan 31/03
ly
System Circuit Breakers
04--40--10
Vol. 1
AUXILIARY POWER UNIT
Control
REV 56, Jan 31/03
Fo
D.
04--40--10
Vol. 1
AUXILIARY POWER UNIT
Control
2
E5
1
R5--6