15.13 Flashcards
What 2 things do you need for the engine to start
Enough air to mix with the fuel and ignition of the mixture
What compressor is used to start the GRE
HPC
What start is used on commercial jet
Air starter
What force is used to start engines
30-50 lbs
Duct presssure line
30 psi
What parts does a pressure regulator valve contain
Valve housing with a butterfly type valve inside
How many engineers are needed for a manual valve override
Two
One in the flight deck
One opening the valve
How many engineers are needed for a manual valve override
Two
One in the flight deck
One opening the valve
What current does a direct cranking electric starter use
Dc
Where are direct cranking electric starting systems used
APU’s and small turbo - shaft engines
What makes a starter generator starting system different
They have a second series of windings that switch to a generator once the engine is at self sustaining speed
What source is required for the starter generator
24 volts and 1500 peak amperes
When is the c field used
Starting purposes only
What needs to be closed to start an engine equipped with a undercurrent relay
Close the engine master switch to complete the circuit
What relays close as the battery and start switch is on
Motor
Ignition
Battery cut out
What figure makes the undercurrent relay open
200amps
When is continuous ignition used
Possibility of a flame out condition
What is the ignition system designed to do
Dual system designed to fire two igniter plugs for safety
What does a typical ignition system include
2 exciter units
2 transformers
2 intermediate ignition leads
2 high tension leads
What does the filter do in the ignition system
Prevents noise being induced into the aircraft system
What the max charge of the a storage capacitor
4 joules
How is the complete exciter sealed
Hermetically for protection
When is a constrained gap plug used
In cooler conditions
How long do you wait before removing high voltage components
20 minutes after shut down
To perform maintenance on the igniter what should you disconnect first
Igniter lead coupling nuts at the exciter end first
What tools can you use on coupling nuts or connectors
Insulated tools and never touched with bare hands
What does the transmission housing also provide
Reservoir for lubricating oil
