week 8 Flashcards
Ignition system only works when?
Engine Start and for certain In-flight conditions
important characteristic of a gas turbine ignition system
high energy discharge at the igniter plug
Ignition units are rated in?
Joules
the larger the engine, the larger the?
Ignition Unit Rating
A large turbofan engine may have ignition ratings of ?
16 joules or more
A smaller engine may have ignition ratings of?
4-6 joules
Larger turbine engines will have one ignition exciter per?
Igniter Plug
Ignition exciters can be classified as?
Intermittent or Continuous Duty
Modern ignition systems use a __ ___ exciter that produces less heat than older models. modern systems are more likely to be considered ____ _____
Solid state, Continuous Duty
What does the Bleed Resistor do?
- Dissipates excess voltage beyond what the igniter plug needs to fire. This allows the plug to fire at the lowest possible voltage. (Typ. 2 joules when igniter is new)
- Provides a discharge path for energy if the system is fired when no igniter plug is installed.
- Bleeding off the capacitor charge when the system is de-energized.
Some smaller gas turbine engines may use __ ___ instead of igniters.
Glow plugs
designed to provide automatic ignition when engine torque or power falls too low. This system ensures ignition during takeoff, landing, turbulence, and during adverse conditions of icing weather
Auto-Ignition System