Engines Flashcards
What are the components of the Engine Fuel System?
Fuel Pump
Fuel/Oil Heat Exchanger
Fuel Metering Unit
Fuel Filter
Variable Stator Vanes
Fuel Injectors
What does the Fuel/Oil Heat Exchanger do?
Maintains the Engine Oil Temperature within an acceptable range and heats the engine fuel to prevent freezing
What does the Fuel Metering Unit do?
Meters and distributes correct amount of fuel for combustion to the injectors
AND
Controls the Shutoff Valve during normal shutdown
AND
Provides Overspeed Protection
What controls the Fuel Metering Unit?
FADEC
What is the purpose of the fuel filter?
To remove contaminants from the fuel
What controls the Variable Stator Vanes
FADEC (via the FMU)
What do the Fuel Injectors do?
Atomise the fuel from the FMU and direct it into the combustion chamber
How many ignitors are energised IN FLIGHT?
2
How many Ignitors are energised ON GROUND?
1
What does the ignition system do and how many ignitors are there?
Provides an electrical spark for fuel combustion
2 Ignitors
What are the 5 Engine Protections?
Hung Start
Hot Start
No Light Off
Overspeed
Overtemperature
When are Hung Start, Hot Start & No Light Protections NOT available?
IN FLIGHT (For In flight Starts)
In the event of an Overspeed, when will the FADEC Automatically command engine shutdown?
N2 102%
In the event of an Overspeed, after how many detections will the FADEC not relight the engine?
3 consecutive Overspeeds within 30 seconds
What controls the ITT limits?
FADEC, varying them according to phase of operation
In the event of Overtemperature during Engine Start when will the FADEC prevent fuel flow?
Temperature above 120°C
What happens if the ITT reaches its Temperature limit during Engine Start?
The FADEC automatically shuts off the fuel flow, aborting the start sequence
In the event the ITT reaches its temperature limit during Engine Start and the FADEC has automatically shut off the fuel flow flow, what must the pilots do?
Turn the START/STOP switch to STOP as the start control valve is NOT automatically closed
What is ATTCS?
Automatic Takeoff Thrust Control System
What controls ATTCS?
FADEC
When is ATTCS available?
Take off & Go Around
What does ATTCS do?
Command RSV (max engine thrust reserve) according to the Take off thrust rating/mode set
What is the default ATTCS Setting?
ON
Where are ATTCS Selections made?
MCDU - TAKEOFF DATA SET MENU
How will you know that ATTCS is ARMED?
ATTCS in WHITE
How will you know that ATTCS is ENGAGED?
ATTCS in GREEN (when thrust levers reach the TO/GA position)
When is ATTCS AUTOMATICALLY activated? (per ATTCS Logic)
ATTCs automatically commands RSV when:
ATTCS ENGAGED
Thrust Levers at TO/GA position
AND one of:
1 Engine Failed on Take off or Go Around
Windshear Detection
Difference Between both Engine N1 Values is greater than 15%
When is ATTCS ARMED during a Go Around?
Whenever the Thrust Rate mode is GA
How can ATTCS be MANUALLY activated?
By moving the thrust levers to MAX whenever ATTCS is engaged
How do you know that ATTCS is activated?
GREEN EICAS ATTCS removed
Cyan Thrust Mode is displayed with RSV
When will you receive RSV in the event of Windshear?
Whenever the thrust levers are set to MAX, even if ATTCS is OFF
What is FLEX?
Reduced take off thrust based on assumed temperature
Where can the Assumed Temperature for FLEX be set?
MCDU TAKEOFF DATA SET MENU|
Assumed temp must be HIGHER than the Takeoff Temperature
What Thrust Modes/Ratings are eligible for FLEX?
All Takeoff Modes/Ratings
TO-1, TO-2, TO-3
Should ATTCS be ON or OFF for a FLEX Takeoff?
Can be either
What is the minimum FLEX takeoff thrust?
75% Max Rated Take Off Thrust
OR
CLB-2 + 1%
Whichever is Higher
What are Engine Thrust Ratings?
Calculated Max N1 for each Engine Thrust Rating adjusted for Altitude, Temp & Airspeed
What are the Engine Thrust Ratings?
TAKEOFF
MAX TAKEOFF RSV
GO AROUND
GO AROUND RSV
MAX CONTINUOUS
MAX CLIMB RATING
MAX CRUISE RATING
IDLE
How many Take off Thrust Ratings are there?
3 - used for normal take off
TO-1
TO-2
TO-3
When is the calculated N1 achieved for the Takeoff Thrust Ratings?
When the thrust levers are in the TO/GA position
When is GA-RSV used?
Extreme situations where extra thrust is required (Highest engine thrust possible)
When is Max CON Thrust Rating Used?
In an emergency where higher thrust than usual is required
When is TO-RSV Thrust Rating used?
Whenever ATTCS is triggered, and its conditions met
When is GA Thrust Rating activated?
Landing Gear & Flaps are down
(Can also be achieved when in any other Thrust Rating Mode and the thrust levers are set to TO/GA)
How many Idle Thrust Ratings are there?
4
FLIGHT IDLE
APPROACH IDLE
FINAL APPROACH IDLE
GROUND IDLE
When is Approach Idle Thrust Rating activated?
IN FLIGHT
Altitude less than 15,000ft
Flaps 1+ or Landing Gear Down
When is Final Approach Idle Thrust Rating activated?
Altitude less than 1200ft AGL
Landing Flaps Set (5 or FULL)
Landing Gear Down
What is the default Climb Thrust Rating?
CLB-1
When is CLB-2 default selected?
When the Takeoff thrust is lower than CLB-1
What happens to the Idle Thrust Rating Calculated Max N1 when Ice is detected?
Flight & Approach Idle - N1 Automatically increased to maintain the minimum bleed pressure required for operation of the anti-ice system
Final Approach Idle - NO N1 Increase
What happens to the Final Approach Idle Thrust Rating Calculated Max N1 when Ice is detected?
No increase
Cyan Dash is displayed on the EICAS N1 dials to show the minimum thrust required to maintain the bleed pressure required for operation of the anti-ice system
What does a CYAN line/dash mean on the edge of the N1 indicator?
Displayed in icing conditions during FINAL APPROACH to indicate the MIN thrust (N1) to meet bleed requirements
What does a Cyan V Bug indicate on the N1 gauge?
N1 Target
How is the Engine FADEC normally powered?
Above 50% N2 - PMA (Permanent Magnet Alternator)
Below 50% N2 or if PMA inop - Aircraft Electrical System
When does the ITT Red line change to AMBER?
After the end of the takeoff phase
What does the ITT Red Line mean?
ITT Temperature Limit
What are the components of the Engine Control System?
FADEC
Thrust Levers
T2 Sensor
N1 Sensor
What controls the Variable Geometry Valves to improve N1 efficiency?
FADEC
How many Channels does the Engine FADEC have?
2
ACTIVE/STANDBY (active alternates every engine start)
What does the T2 sensor do?
Monitor Engine INLET air temperature
What does the N1 Sensor do?
Provides Fan Speed data & monitors aircraft vibration
What are the key elements of the Start & Ignition Process on ground?
7% N2 - FADEC initiates ignition
20% N2 - Fuel Flow Introduced (Metering Valve Opens)
50% N2 - when Light off occurs > Ignition OFF and FMU accelerates engine to ground idle speed
During Engine Start, what happens if No Light Off is detected within 15 seconds of Fuel ON?
FADEC automatically turns off ignition and fuel, and continues dry motoring for 30 seconds, tries single ignition and fuel ON again
During Engine Start, what happens if No Light Off is detected after 30 seconds of Dry motoring and a further single ignition/fuel ON attempt?
After 7 seconds, FADEC commands DUAL ignition for 8 seconds
If no LIGHT OFF is detected after 15s of the reintroduction of fuel or after start duty limit is reached (whichever occurs first), the FADEC does not turn off fuel or ignition automatically . Need to manually abort.
During an Auto Relight in Flight what indications would you expect to see next to the N2 indication?
A WML icon
How many ignitors are energised during an auto relight?
2
When is an Auto Relight considered unsuccessful?
If the engine does not relight within 30seconds or if the N2 falls below 7.2%
How can an engine be restarted in flight?
Engine Crossbleed Air
APU Bleed Air
Windmilling
What are the steps for Windmilling Engine Start in Flight?
7% N2 - FADEC initiates ignition
7.2% N2 OR after 15 seconds (whichever comes first) - Fuel Flow Introduced (Metering Valve Opens)
What are the key elements of the Start & Ignition Process IN FLIGHT?
7% N2 - FADEC initiates ignition
20% N2 - Fuel Flow Introduced (Metering Valve Opens)
> Fuel Flow automatically introduced if N2 has not reached 15% after 15 seconds
50% N2 - when Light off occurs > Ignition OFF and FMU accelerates engine to ground idle speed
When are BOTH ignitors energised?
Engine Start IN FLIGHT
Engine Air Start
Engine Flameout
Missed Light Off
Cold Soak Condition on GROUND
Ground Starts at HIGH altitude
Ignition Selector Knob in the OVRD position
What are ignitors 1 & 2 connected to?
SPDA 2
What happens to the ignitors if SPDA 2 Fails?
Setting the selector knob to OVRD will energise at least ignitor A
What happens if the ITT limit is exceeded during an in-flight start?
FADEC interrupts the fuel flow for 4 seconds and then resumes the start
(This can be repeated 8 times until the logic is no longer available)
Pilots must still monitor engine parameters and manually abort the start where necessary
What does the Starter Control Valve do?
Provides Bleed Air from the APU, other Ground Source or Opposite Engine
When does the Starter Control Valve Close?
When the starter cut out speed is reached
What are the components of the Starting System?
Air Turbine Starter (ATS)
Starter Control Valve (SCV)
What is the ATS (Air Turbine Starter)?
A turbine that accelerates the engine to a self sustaining RPM level - supplied by Bleed Air from the Pneumatic System
What are the components of the Engine Lubrication System?
1 x Oil Tank
1 x Oil Pump
1 x Oil Filter
PER ENGINE
What does the Engine Lubrication system do?
Lubricates and cools the engine shaft bearings and accessory gearbox
What is the normal range for Engine Vibration?
0-3.9
What is the cautionary operating range for engine vibration?
4-5
What kind of Engine does the Embraer 190 have?
General Electric CF34-10E
Max Thrust of the Engine?
18500lb
What type of engines do the Embraer 190 have?
High Bypass, Dual Rotor Turbofans, 4 stage low pressure turbine, 9 stage axial flow compressor
What are the N1 & N2 Rotors?
N1 - Fan
N2 - Compressor
Where are the thermocouples and how many are there?
5
Located int he inlet stream of the low pressure turbine
What is the purpose of the Variable Stator Vanes?
Optimise the Position of the Compressor stators as a function of corrected N2 to provide optimum compressor efficiency
How many thrust reversers are there?
2
How are the Thrust Levers Locked?
2 Actuator Locks
1 Independent Cowl Lock (to prevent inadvertent deployment)
How are the thrust reversers actuated?
Hydraulically
What happens if 1 thrust reverser fails with MAX REV selected on both engines?
Operative Thrust Reverser provides minimum reverse thrust only
BUT
Selecting ONLY the operative Thrust Reverser to MAX REV enables max thrust on this engine - both thrust levers will need to have been moved to IDLE to reset the system to do so
What does an AMBER REV displayed below the N1 indication dial represent?
The Reverse Cowl is in Transition
What are the 2 Reverse Thrust Settings?
Min REV & MAX Rev
How is Max Thrust Commanded?
By holding the levers in the MAX REV position, letting go will revert them to MIN REV
