Chapter 7 - Engines, APU Flashcards
1
Q
If engine oil pressure is in the amber band with takeoff thrust set:
A
DO NOT TAKEOFF.
2
Q
The position of the engine BLEED air switches during the shutdown procedure is:
A
ON.
3
Q
The indications that the engine starter has disengaged are:
A
- The ENGINE START switch returns to OFF at 56% N2,
- START VALVE OPEN alert extinguishes.
4
Q
The amber DUAL BLEED light is illuminated after engine start. What should the pilot do?
A
Limit engine thrust to idle and or place the APU BLEED AIR switch to OFF.
(Prevents back pressure of the APU)
QRH 2.13
5
Q
Which hydraulic system during normal operations powers the thrust reversers?
A
System A for engine No.1 and system B for engine No.2.
(Sequential, A1, B2)
6
Q
The thrust reverser may be deployed:
A
- When either radio altimeter senses less than 10 feet altitude or
- When the air/ground safety sensor is in the ground mode
7
Q
Which APU annunciator light is not associated with an automatic shutdown of the APU?
A
MAINT
8
Q
An APU shutdown in flight occurs:
A
Automatically by moving the battery switch to OFF
9
Q
The APU may be used as an electrical and bleed air source simultaneously up to:
A
10,000 feet.
10
Q
Engine EEC abnormal start protection:
A
is provided for EGT protection on the ground only.
11
Q
If the upper DU fails:
A
engine indications automatically shift to lower DU.
12
Q
When the EEC is not powered the following indications are displayed directly from the engine sensors:
A
N1, N2, oil quantity and engine vibration
13
Q
During start, when the EEC is not being powered:
A
Only N1, N2, oil quantity and engine vibration are available and are displayed directly
from the engine sensors
14
Q
The EEC hard alternate mode thrust is:
A
always equal to or greater than normal mode thrust for the same lever position.
15
Q
The EEC provides redline overspeed protection for:
A
N1 and N2 in both the normal and alternate modes.
16
Q
What position must the forward thrust levers be in before reverse thrust can be selected?
A
Idle thrust position
17
Q
The EEC automatically selects approach idle in flight anytime:
A
The flaps are in the landing configuration or engine anti-ice is ON for either engine
18
Q
The APU starts and operates up to:
A
41,000 feet.
19
Q
Regarding the APU, both transfer busses can be powered:
A
On the ground or in-flight
20
Q
The APU supplies bleed air for both air conditioning packs:
A
On the ground only
21
Q
APU cooling air:
A
enters through a cooling air inlet above the APU exhaust outlet.
22
Q
Electrical power to start the APU comes from:
A
number 1 transfer bus, or airplane battery(ies)
23
Q
With AC power available, the starter generator uses AC power to start the APU. Without AC
power available, the starter generator uses battery power to start the APU.
A
true
24
Q
The APU start cycle may take as long as:
A
120 seconds.
25
The APU electronic control unit (ECU) provides automatic:
* shutdown protection for overspeed conditions, low oil pressure, and high oil
temperature.
* shutdown protection for APU fire, fuel control unit failure, and EGT exceedance.
* automatic control of APU speed through the electronic fuel unit.
26
If the APU is the only source of electrical power:
in flight, the galley busses are automatically shed
27
If a wet start is detected, the EEC turns off the ignition and shuts off fuel to the engine:
15 seconds after the start lever is moved to IDLE during ground starts.
28
Regarding the APU, moving the battery switch to OFF
Automatically shuts down the APU because of power loss to the electric control unit.
29
Moving the APU switch to OFF:
* trips the APU generator.
* closes the APU bleed air valve.
* extinguishes the APU GEN OFF BUS light.
30
Starter cutout speed is:
Approximately 56% N2.
31
Thrust Mode Display
N1 Set Outer Knob - AUTO
Active N1 limit is displayed by reference N1 bugs.
32
Thrust Mode Display
N1 Set Outer Knob - Other than AUTO
The thrust mode display annunciation is MAN.
33
General engine details:
CFM56-7 rated at 27,000lb of thrust
34
How is N2 operating speed determined?
By the EEC.
35
Total thrust =
Fan discharge airflow + primary airflow
36
TAT is used to calculate the following N1 limits:
* CLB
* R-CLB
* CRZ
* G/A
* CON
37
A/T LIM:
Single degraded N1 limit being computed by the EEC
38
Green N1 reference bug indicates:
FMC N1 limit or the manually set N1 reference
39
Green N1 reference bug indicates:
FMC N1 limit or the manually set N1 reference
40
What does a series of dashes indicate above the N1 digital display box?
FMC N1 limits not available with AUTO selected
41
What indication shows to remind crew after an in-flight engine RPM exceedance occurred?
Red N1 box after shutdown.
42
How is max EGT limit indicated during start?
Red line and appears until 59% N2 reached
43
How is an exceedance of max continuous EGT displayed?
Amber EGT display when max continuous EGT exceeded for more than 5 minutes.
44
ENG FAIL alert appears when:
N2 RPM decreases **below 50%** with start lever in **idle**.
Remains until N2 RPM **above 50%**, start lever moved to **cutoff**, or engine **fire switch pulled**.
45
Secondary engine indications display on the lower DU when:
* **Power** initially applied to the system
* When ENG selected on **MFD**
* When a secondary engine indication **exceeds** normal range
* In-flight when an engine **failure** occurs or start lever moved to **cutoff**
46
When are the igniters activated?
When the EEC detects an uncommanded and **rapid decrease in N2** or when **N2 decreases below idle** RPM.
47
The amber band for the oil pressure is not displayed when:
N2 RPM less than **65%**
48
LOW OIL PRESSURE annunciator displays when:
**PSI** is less than **13**. It blinks for **10 seconds** then displays steadily.
49
How is low oil quantity displayed?
Oil quantity box changes to **reverse video** and **LO** appears.
50
What powers the EEC?
AC Transfer Bus 1 until 15% N2 achieved on start then a dual redundant generator
51
What is the interface for the EEC?
The EEC receives and sends engine control and engine data via DEU's.
52
How does the EEC calculate N1?
Sensed flight conditions and bleed air demand
53
When is hard alternate mode selected on the EEC?
When the pilot pushes the EEC switches or when the EEC is in soft mode and thrust levers are reduced to idle.
54
Why would exceedances occur in soft alternate mode on the EEC?
Because the EEC locks in the last valid flight conditions and therefore the data is old.
55
What is the main difference between the soft and hard alternate EEC modes?
There is **no thrust offset** on the **hard** EEC mode.
56
How is an alternate EEC mode annunciated?
1. MASTER CAUTION light
2. ENG annunciator light
3. ALTN light in EEC switch
57
What protection is provided by the EEC's?
Redline overspeed protection in normal and alternate modes for both N1 and N2 spools.
(EGT redline protection not provided)
58
Conditions for the ENGINE CONTROL lights:
1. engine operating
2. aircraft on the ground
3. below 80kts on takeoff or 30 seconds after touchdown.
59
What caused the FILTER BYPASS light to illuminate?
Pressure differential between the input and output pressure across the fuel filter that might cause the filter bypass valve to open.
60
Where is the fuel shutoff valve located?
At the HMU
61
What conditions are required for the spar and engine fuel valves to be **open**?
1. start lever **IDLE**, **and**
2. fire switch **in**.
62
What conditions are required for the spar and engine fuel valves to be **closed**?
1. start lever **CUTOFF**, **or**
2. fire switch **pulled out**.
63
Engine Valve Closed (ENG VALVE CLOSED) and SPAR VALVE CLOSED Lights illuminate DIM when:
The related engine or spar fuel shutoff valve is closed.
64
Engine Valve Closed (ENG VALVE CLOSED) and SPAR VALVE CLOSED Lights illuminate BRIGHT when:
The related engine or spar fuel shutoff valve is in transit, or valve position and engine start lever or engine fire switch disagree.
65
Engine Valve Closed (ENG VALVE CLOSED) and SPAR VALVE CLOSED Lights are extinguished when:
The related engine or spar fuel shutoff valve is open.
66
The OIL FILTER BYPASS light relates to the bypass of:
The scavenge filter.
67
Where does the oil go after the scavenge filter?
To the fuel/oil heat exchanger where it is cooled by the engine fuel flow.
68
In what metric is engine oil displayed?
percentage full
69
Under what conditions is it normal for engine oil pressure to indicate amber and why?
When engine is at idle power or when the oil is warm eg during idle power descent. This is because the oil pump provides unregulated pressure.
70
The blinking feature of the low OIL PRESS indication is inhibited during:
takeoff or landing
71
How is oil temperature information delivered?
Via a temperature sensor to the EEC which supplies the information to the lower DU.
72
What powers the engine start valve?
The battery electrically signals the pneumatic start valve to open.
73
IGN L is powered by:
The AC Transfer Bus
74
IGN R is powered by:
The AC Standby Bus
75
The starter is _____ operated:
pneumatically
76
What also occurs when the start valve opens?
The engine bleed valve closes.
77
What does the starter rotate?
The N2 spool through the accessory drive and airflow will rotate the free N1 spool.
78
The red EGT limit displays during an engine start until N2 RPM reaches \_\_\_%
59%
79
What occurs at 25% during engine start?
- start lever raised to IDLE
- spar valve opens
- EEC opens fuel shutoff valve
- igniter circuit completed to provide ignition
80
The start switch is magnetically held in the GRD position until the N2 RPM exceeds \_\_\_%
56%
81
What occurs when the start switch automatically returns to OFF?
- the start valve is signaled to close
- the engine bleed valve close signal is removed
- START VALVE OPEN alert blanks when the start valve closes
82
- takeoff
- landing
- flight in precipitation
- icing conditions
(only IGN L or IGN R will operate)
83
When is FLT used for the engine igniters?
- heavy precipitation
- inflight engine starts
84
The EEC provides protection for the following conditions during ground starts:
- impending hot starts
- EGT start limit exceedance
- wet starts
85
If the EEC detects a rapid EGT rise or an EGT approaching the start limit:
The white box around the digital EGT display flashes.
86
After the EEC detects a rapid EGT rise or an EGT approaching the start limit, the flashing white box resets when:
The start lever is moved to CUTOFF or the engine reaches idle N2.
87
What occurs when the EGT exceeds the start limit?
The box around the digital display and the dial turn red and the EEC automatically turns off the ignition and closes the engine fuel shutoff valve.
88
When setting up the cockpit, a red box appears around the digital EGT display. What occurred?
EGT exceedance.
89
Wet start protection?
EEC turns off the fuel and ignition if there is no fuel increase within 15 seconds after placing the start lever to IDLE.
90
How can an in-flight start be made?
Either pneumatic starter assist or windmilling.
91
How would you know if it is not possible to use windmilling to start the engine?
X-BLD START appears appears above the N2 display.
92
When is flameout protection activated?
When the EEC detects:
- a rapid decrease in N2 or
- when N2 decreases below idle RPM
93
Which system is used in lieu of the normal hydraulic system for the related thrust reverser?
Standby system
94
Reverse thrust is not available on landing until:
10' or less radalt or air/ground sensor is in ground mode
95
**Maximum** reverse thrust is available when:
The thrust level moves past the second detent.
96
**Normal** reverse thrust is available when:
The thrust lever is moved from the first to the second detent.
97
It is normal to observe an amber REVERSER light on the aft overhead panel when:
The reverser is commanded to stow because the isolation valve must remain open to provide hydraulic pressure to the control valve which is in the stow position.
98
The MASTER CAUTION light and ENG annunciator appear when a reverse is commanded to stow and REVERSER light remains illuminated for longer than:
12 seconds
99
With a reverser disagreement inflight:
The reverser is hydraulically held in the stow position until the aircraft lands and reverse is selected.
100
How many panels have controls associated with the APU?
1. Fuel Panel
2. Generator Control Panel
3. Pneumatic Panel
4. APU Control Panel
101
There are ___ annunciator lights on the APU Control Panel:
1. MAINT
2. LOW OIL PRESSURE
3. FAULT
4. OVERSPEED
102
The OFF position of the APU control switch shuts down the APU after how many seconds?
60
103
The ON position of the APU switch:
- energises the APU control circuits
- opens the APU fuel valve
- arms the APU annunciator lights
104
The EGT indicator of the APU is depowered ___ minutes after shutdown.
5
105
A common reason for the APU MAINT light to indicate is:
Low oil quantity
106
Which annunciator light is normal during APU start?
LOW OIL PRESSURE
107
If a LOW OIL PRESSURE light appears during APU operation:
The APU will automatically shutdown and the APU annunciator light and MASTER CAUTION light will illuminate.
108
The FAULT light for the APU indicates:
A malfunction causing the APU to automatically shutdown. It will extinguish after 5 minutes after the APU switch is selected to OFF.
109
The OVERSPEED light for the APU indicates:
An APU shutdown due to an overspeed. It will extinguish after 5 minutes after the APU switch is selected to OFF.
110
Commonalities between APU annunciator lights:
All except MAINT result in an automatic APU shutdown and the light remains illuminated until 5 minutes after the APU switch is placed to OFF.
111
What occurs if no boost pumps are operating when the APU switch is moved to the start position?
The APU will suction feed from Tank 1
112
Can the right CTR Tank Fuel Pump be used to supply the APU?
Yes, though the crossfeed must be open.
113
Starter power to the APU can be supplied by either:
The battery or the #1 AC Transfer Bus
114
What occurs when the APU generator switch is placed to ON and the engine generators are not ON?
1. The APU generator powers both AC Transfer Buses,
2. Removes external power from the buses (if on) and
3. Illuminates the opposite SOURCE OFF light until related generator placed on the bus.
115
What happens when the APU generator is supplying both Transfer Buses and one APU generator switch is moved to OFF?
The associated SOURCE OFF light illuminates but does not remove power rom the aircraft.
116
What happens when the APU generator is supplying both Transfer Buses and both APU generator switches are moved to OFF?
The APU generator is disconnected from the Transfer Buses and the APU GEN OFF BUS light illuminates.
117
The APU GEN OFF BUS light illuminates when:
APU RPM is above 95%
118
What generally causes electrical shedding on the APU?
High EGT.
119
What is the difference between APU load shedding during APU start and APU operation?
During start, electrical load is shed to preserve bleed air extraction, where as during operation, electrical loads are preserved whilst bleed air extraction is reduced.
120
What is automatically shed if the APU is the sole power source?
Gally and Main buses
121
If the battery switch is turned off (on the ground or in-flight) the APU:
Will automatically shutdown as the ECU loses power.
122
For how long and why should you wait to turn off the Battery Switch after APU shutdown?
20 seconds to allow time for the air inlet door to close
123
APU auto shutdown occurs when the following occur:
1. LOW OIL PRESSURE light
2. FAULT light
3. Turbine Overspeed
4. FIRE WARN light
5. Battery Switch OFF
