Study Guide Engine Flashcards
What types of engines are on the aircraft?
-TWo GE CF-34-8E5 Hi-Bypass, 2 spool, axial flow, turbo fan
How much thrust do the engines produce?
13,800-14,200
Describe N1 spool
Single stage fan, 4 stage LP turbine
Describe N2 spool
10 stage compressor, 2 stage HP turbine
How many ignators per engine?
2 per
How many ignitors activate for engine start?
Ground
- 1 igniter (switch in AUTO)
- 2 igniters (switch in AUTO)
What happens when the ignition switch is selected to OVRD?
Activates both igniters on the ground and 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 while the other is standby. They alternate with each start
What does the Cyan line on the N1 gauge represent on approach and when does it appear?
- 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 (Air)
- Opposite engine
- Windmilling
Does the FADEC provide engine start protection?
Only on the ground for a hot, 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
Describe the engine start sequence
Start switch to start
- 7% N2 ignition
- 20% N2 Fuel flow
- 20% N2 +5 seconds Light off
- 50% N2 ignition off
Engine stabilizes:
- N1 27%
- ITT 460 C
- N2 62%
- FF 550 lbs/hr
- Oil pressure >25psi
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 re-light the engine
What heats the fuel and cools the engine oil?
Fuel/Oil heat exchange
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 and ATTCS event?
- N1 difference >15% between engines
- Engine failure during TOGA
- Wind shear 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 ratings 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