Powerplant Flashcards
What is the bypass ratio of the engine?
5 to 1
How many stages are in the compressor section?
14
How many stages are in the high pressure turbine?
Two
How many stages are in the low pressure turbine?
Three
What is compressor Variable Geometry?
The inlet guide vanes and first five stators move using fuel pressure to improve efficiency and reduce compressor stalls
How many FADECs does each engine have?
Two - A and B
Which sections of the engine comprise the N1 spool?
Fan and low pressure turbine
Which sections of the engine comprise the N2 spool?
Compressor and high pressure turbine
Is N1 or N2 speed used to set thrust?
N1
How many blades does the fan have on the A1P engine?
24
Where does air for the precooler come from?
The engine fan
How is the body of the aircraft protected from a fan blade detaching?
N1 containment ring - kevlar surrounding the fan
What controls how much fuel to send to the CVG actuators?
The FADEC
Which stages of the compressor supply air for the pneumatic system?
9th and 14th
What type of combustion chamber does the engine have?
Annular
How many fuel nozzles does the engine have?
16
How many igniters does the engine have?
Two
What is the purpose of the forced mixer?
To reduce noise
What items are on the accessory gear box?
Air Turbine Starter (ATS)
Fuel pump and metering unit (FPMU)
Generators (2)
Hydraulic pump
Oil pump
Permanent Magnet Alternator (PMA)
What controls how much fuel is sent to the fuel nozzles from the FPMU?
The FADEC
What pump in the FPMU allows the engine to suction fuel from the wing tanks?
Gear Pump
Is the engine oil system a dry sump or wet sump system?
Dry sump
What is the capacity of the engine oil tank?
12 qt
What two heat exchangers are used to cool the engine oil?
Air Cooled Oil Cooler (ACOC)
Fuel Cooled Oil Cooler (FCOC)
What area of the engine are lubricated with oil?
Aft sump
Center sump
Forward sump
Fan sump
Accessory Gear Box
How is the engine oil pump protected from debris in the system?
Filter screens on all oil scavenge inlets
Magnetic chip detectors on all inlets except accessory gear box
What does the PMA provide power for?
FADEC above 50% N2
Igniters above 10% N2
What provides power for the FADECs?
Above 50% N2: PMA
Below 50% N2: 28V DC system
What provides power for the igniters?
Above 10% N2: PMA
Below 10% N2: No power, the PMA is the only source of power for igniters
What air sources can be used to start the engines?
APU
External pneumatic start
Opposite engine
Windmill start inflight
What information does the engine FADEC share with the opposite engine’s FADEC?
ATTCS
Thrust reverser interlock
What percent N2 determines whether the engine is running or not?
56.4% N2
What are the four thrust mode buttons?
T/O, CON, CLB, CRZ
What happens when the ignition Selector is set to OFF?
Ignition and fuel are inhibited to allow for dry motoring
With ignition set to AUTO, when will igniters activate?
Ground Start: One ignitor at 14% N2
Air start: Both igniters at 10% N2
With ignition set to ON, when will igniters active?
Both igniters at 10% N2
What needs to be set for TAKEOFF DATA prior to takeoff?
Takeoff thrust mode
Takeoff temperate
Anti-Ice on or off
What position does the thrust lever need to be in to shut down the engine normally?
Idle
Name and describe the three idle ratings?
Ground idle is a speed sufficient to provide bleed air, sustain engine operation and drive the AGB
Flight idle is a higher minimum thrust to allow engine to accelerate to maximum within eight seconds
Anti ice flight idle is higher than flight idle and provides required bleed air for anti ice
When will the thrust mode automatically be set to the maximum takeoff thrust mode?
Below 15,000 feet with landing gear down and locked
If ATTCS is armed, what happens when an engine fails?
The operating engine thrust mode automatically increases to the next higher level
If the thrust Levers are forward of the detent, can CRZ, CLM, or CON modes be selected?
No
What happens to engine thrust if the thrust levers are moved forward of the detent during takeoff?
ATTCS no longer armed, Engine thrust increases to maximum thrust
On the EICAS, what color/symbol represents N1 target?
Blue T on N1 indicator, and blue digits to the left and right of the thrust mode indication
On the EICAS, what color/symbol represents N1 request?
Green Bug on N1 indicator, and green digits in the box at the top of the display
What engine oil level causes the indication to be displayed in amber?
less than 6 quarts
What prevents the thrust reversers from being selected in flight?
Electrical and mechanical stops
What locks prevent the thrust reversers from deploying in flight? How are the locks commanded and actuated?
Primary - Electrically commanded, hydraulically actuated
Secondary - Electrically commanded, hydraulic actuated
Tertiary - Electrically commanded, electrically actuated
What will the engine response be if a thrust reversers deploys in flight?
FADEC commands idle thrust
How does the FADEC prevent asymmetric thrust reverse thrust?
No reverse thrust unless both reversers on both engines are completely deployed. If single engine, the failed engine thrust lever must not be in reverse.
What conditions allow maximum reverse thrust?
One of the following:
- Both main landing gear on the ground, and wheel speed greater than 25 kt
- All three landing gear on the ground
What does REV displayed in amber on the EICAS indicated?
Reversers are in transit
What does REV displayed in green on the EICAS indicated?
Reversers are fully deployed
Below what speed should the thrust reversers be limited to idle thrust?
60 KIAS
Below what speed should the thrust reversers be stowed?
30 KIAS