Starting & Ignition System Flashcards
What is the start lever used for
Switch fuel on/off and switch ignition on
What is the forward thrust lever for
Control thrust of an engine between idle and take off
What does reverse thrust lever do
Deflected doors are deployed and the airflow is deflected to give reverse thrust
What does master lever do
Control engine start sequence
When does hp valve open
When engine start lever moved up
how HP fuel shut off valve controlled
Mechanically
On the A320 how is HP fuel valve controlled
Electrically by engine master switch
Mechanical thrust control positions
Idle and take off
Where does mechanical thrust control transmit lever input signals to
fuel control unit on engine
Positions of reverse thrust lever
Reverse idle and full reverse thrust
What does a friction brake do
Uses internal friction to keep the throttle control system in a selected position
Why does a friction brake need to be strong
Strong enough to prevent movement from vibration
What switch activates thrust reversers
Micro switches below the centre pedestal
What system does foward system not have but reverse thrust system does
Reverse has throttle interlock system
What does the electrical thrust control do
Use electrical signals to transmit thrust demand signal from thrust control levers in cockpit to engine
What is a resolver
Electrical component that Coverts angular deflections of input lever to an electrical system
How may resolvers for each control lever
2
What does artificial feel do
Stimulate higher resistance
What is start ignition used for
To begin combustion
What is continuous ignition used for
Incase external conditions lead to flame out condition
What does exciter do
Generates high voltage
What provides sparks
Igniter plug
What does igniter lead do
Transport electrical energy from exciter to plug
What’s the purpose of a two igniter system
For safety purposes
What are the two igniter systems
A & B system
When are the A & B systems activated
During continuous combustion
What part of the exciter should you never touch
During maintenance never touch output of ignition exciter including lead contacts
What material are modern igniter plugs
Ceramic
What should you check with igniter plus
Correct immersion depth
What do two blue rings indicate
Toxic beryllium oxide
How far can leads travel
Several meters
What cools igniter leads
Air from engine compressor
Why do we need to cool copper wire
Copper wire increases resistance when there’s a increase in temperature
What 2 ways are starting systems controlled
Pneumatically or electronically
Why is in flight restart needed
Saftey reasons on commercial aircraft
starter motor operates through what gearbox
Engine compressor through accessory gearbox
What’s higher idle & starter cut out speed or self-sustaining speed
Idle & starter cut out speed
What starting system is used of commercial jet engines
Pneumatic
What’s used to operate pneumatic starter motor
Bleed air from the apu , another engine or ground cart
How is air supplied to starter motor
Starter air duct
How is air supply switched off/on
Starter shut off valve
Why is starter shut off valve in the lower are of engine
Easy access to maintenance crew
What 2 ways is the starter valve controlled
Electrically by solenoid
Pneumatically operated by air pressure from starter duct
