What happens when the ignition switch is selected to OVRD?
Activates both igniters on the ground or in flight
Can the igniters be turned off during flight?
• The switch may be moved to the OFF position but the FADEC disregards the command
• The OFF position is used for dry motoring on the ground only
What controls the engine?
• A two-channel FADEC
• One channel is active and the other channel remains in standby as a backup
Is only one FADEC channel used every flight?
No. They automatically alternate with each engine start
What does the cyan line on the N1 gauge represent during approach? When does it appear?
• The minimum N1 for bleed requirements in icing conditions
• Configured for landing < 1200’ RA (when anti-ice is ‘ON
What sources are available for engine starting?
• APU
• Ground source (huffer cart or air bottle)
• Opposite engine
• Windmill start
Does the FADEC provide engine start protection
Only on the ground for a hot start, hung start or no light-off
What will the FADEC automatically do in case of a Hot start?
• FADEC will not allow FF if ITT >120°C
• FADEC will automatically dry motor engine and introduce fuel when ITT <120°C
Describe the engine start sequence
• Start switch momentarily to START:
7% N2 Ignition
20% N2 Fuel flow
20% N2+ 5 sec Light-off50%
N2 Ignition off
• Engine stabilizes:
N1 27%
ITT 460°C
N2 62%
FF 550 lbs/hr
Oil Pressure >25 psi
What does WML mean on the engine indications?
• Windmilling engine
• The FADEC has detected a flame-out and is attempting an auto re-light, or
• An assisted start has been commanded
What provides underspeed and overspeed protection?
• The FADEC via the FMU
• Approximately 52% N2 and 102% N2 respectively
What happens after 3 overspeed detection events?
FADEC will not command an auto re-light to the engine
What heats the fuel and cools the engine oil?
Fuel/Oil heat exchanger
What is ATTCS? What controls it?
• Automatic Take-off Thrust Control System
• Provides max thrust reserve (RSV) according to current rate previously selected via the MCDU
• FADEC controlled
What will trigger an ATTCS event?
• N1 difference >15% between engines
• Engine failure during TOGA
• Windshear detected
When is thrust reverse available?
Weight-on-wheels (ground use only)
What happens if a thrust reverser inadvertently deploys?
FADEC limits respective engine thrust to IDLE
What engine thrust rating(s) may only be used for 5 minutes?
• TO-1• TO-RSV (TL beyond TOGA)
• GA (two-engine go-around)
• GA-RSV (one-engine go-around or windshear)
What is FLEX?
Reduced takeoff thrust based on assumed temperature (telling the FADEC that it is warmer than it actually isso it will reduce the thrust)
Can the FLEX thrust be reduced lower than CLB thrust?
no
Route of oil through the engine
Oil reservoir
Lubrication pump
Passes through the filter and fuel oil heat exchanger
Then divided into several paths to lubricate the turbine engine main shaft bearings and the accessory gear box.
Scavenge pump sends oil back to the reservoir
If the engine relight does not occur within _____ seconds or N2 falls below ____%, the auto relight can be considered unsuccessful and shoukd be manually terminated.