Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

M15✅ > 15.13 STARTING AND IGNITION > Flashcards

15.13 STARTING AND IGNITION Flashcards

1
Q

2 separate systems are required to ensure gas turbine engine will start satisfactory which are

A
  • compressor and turbine to be rotated at an adequate speed (to produce sufficient air)
  • ignition of air/fuel mixture
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Is it possible for the motor of the engine to operate without ignition

A

Yes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

How is a gas turbine engine simply started

A

Rotating high-pressure compressor

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

The starter must continue to assist the engine until what?

A
  • reaches self-sustaining speed
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Why must the torque supplied by the starter be excessive

A
  • to overcome compressor inertia and friction loads of engine compressor
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Once there is sufficient airflow established through the engine, what occurs

A
  • ignition turned on, followed by fuel
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Why must the starter continue to assist the engine above self-accelerating speed

A
  • to avoid delay in the starting cycle
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Explain cartridge starter

A
  • quick independent method of starting
  • small impulse type turbine that is driven by high velocity gases from a burning cartridge
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

How is the cartridge ignited

A

By applying voltage

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

To achieve a cartridge start, it is first placed where

A

Breach cap

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Explain a air starter

A
  • motor transmits power through a reduction gear and clutch to the starter output shaft
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Where is the air taken from for the starter turbine to rotate

A
  • external ground supply
  • APU
  • cross feed from a running engine
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Only 1 source of around 30-50psi is used at a time to start the engines

A

True

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What happens to the clutch as the engine accelerates up to idling r.p.m

A
  • automatically disengages
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What clutch assembly engages automatically as soon as the rotor starts to turn but disengages as soon as the drive coupling turns more rapidly than the rotor side

A

Sprag clutch assembly

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What oil does the starter use

A

Turbine oil

17
Q

Is the starter easy to remove for maintenance

A

Yes

18
Q

If the air starter valve fails to open what happens

A
  • there is a manual valve which overrides to allow engine start
19
Q

What are the 2 electric starter systems

A
  • direct cranking electrical systems
  • starter generator systems
20
Q

Explain direct cranking electrical starter

A
  • DC electric motor
  • common on small turbine engines, such as APU and turbo-shaft engines
21
Q

Explain starter generator starting system

A
  • most gas turbines are equipped with this
  • Like direct cranking electrical systems, except they also contain a second series of windings
22
Q

Explain starter generator engagement

A
  • permanently engaged with engine shaft necessary drive gears
23
Q

Explain direct cranking starter engagement?

A
  • employ some means of disengaging the starter from the shaft after engine has started
24
Q

The starter generator is a shunt generator

A

True

25
Q

When would continuous ignition be used

A
  • if there is a possibility of engine flame out
  • e.g. used for landings
26
Q

Most turbine engines are equipped with what type of ignition system

A
  • high-energy capacitor type ignition system which are air-cooled by fan airflow
27
Q

As a safety factor how many igniter plugs are fired

A

2

28
Q

Once combustion has been initiated what happens to the flame

A

It is continuous

29
Q

Each discharge circuit incorporates how many storage capacitors

A

2

30
Q

What is a exciter

A
  • dual unit producing sparks at each of the 2 igniter plugs
  • continuous series of sparks is produced until engine starts
31
Q

Explain annular gap ignitor plug

A
  • projects slightly into combustion chamber liner to produce more effective spark
  • known as ‘long reach ignitor’
32
Q

Explain constrained gap plug

A
  • operates at cooler temp
  • does not project into combustion chamber liner

M15✅ (16 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions