Turbine Ignition & Starting Flashcards
What is the turbine engine starting sequence?
Starter > Ignition > Fuel
The result of more fuel in a turbine engine:
More speed.
What does it mean to perform a check?
Verify operation
What is a hung start?
The turbine engine will not accelerate to self sustaining speed.
What is a hot start?
Turbine engine EGT exceeds the max limit.
When is a hung start likely to occur?
When the starter is disengaged too soon.
When is a hot start likely to occur?
When the fuel is introduced to early.
How many exciter units are required by Far 33?
Two.
Two heat introduction methods in turbine engines:
1) Igniters
2) Glow Plugs.
The component that releases the charge in an exciter unit:
Trigger capacitor
A schedule that allows a device to operate for a given period of time, followed by a cool down period before the device can be operated again:
Duty cycle
T/F
Exciters are normally not serviced in the field.
True.
T/F
Input voltage to an exciter may be A/C or D/C.
True.
All exciters are ______ capacitance discharge.
High tension.
Relights the engine in the case of a flame out:
Auto-ignition system
The ______ drains energy from the capacitor of an exciter after power is cut off.
Bleed resistor
Benefits of turbine igniters over spark plugs:
1) No fouling (due to hotter burn)
2) Longer life (not running constantly & no direct flame exposure)
T/F
Starters have no fuse.
True
Process for disconnecting lead from an exciter or igniter:
1) Pull circuit breaker (lock out)
2) Disconnect power lead to the exciter.
3) Wait the MM specified time.
4) Remove igniter lead and ground to engine.
Provides the compressed air needed for starting most jet transport airplanes:
APU
3 types of air supplies for air turbine starters:
1) APU
2) GPU
3) Cross flow from other engine.
The starter motors which compressor?
N2 (high pressure compressor)
Two ways a butterfly valve for a pneumatic starter is operated:
1) Manually with a t-handle Allen wrench.
2) Via fly weight controls.
Two methods of protecting the pneumatic starter from over speeding:
1) Choke nozzle slows incoming air.
2) Sheer section air supply is not shut off.
What component activates the auto ignition?
Bellows.
What to look for when inspecting a starter:
1) Brush damage and wear.
2) Signs of arcing.
3) Commutator damage.
4) Solder missing.
Primary advantage of an air turbine starter:
Low weight to torque ratio.
The type of starter used by most small business jet turbine engines:
Starter generator
Types of combustion starters:
1) Cartridge
2) Gas turbine
Where is the APU located?
Tail cone
Two things supplied by APU:
1) Electrical power
2) Compressed air
What controls the fuel on most APUs?
FADEC
Main components of a turbine engine ignition system:
1) Exciters
2) Leads
3) Igniters
What type of DC motor is commonly used for recip engine starters and why?
Series wound, because it has a higher starting torque under heavy load conditions.
3 types of electric starters for general aviation aircrafts are starters with:
1) Overrunning clutch
2) Bendix drive
3) Right angle drive adapter
