Use LEFT and RIGHT arrow keys to navigate between flashcards;
Use UP and DOWN arrow keys to flip the card;
H to show hint;
A reads text to speech;
28 Cards in this Set
- Front
- Back
What is the main advantage of a Magneto Ignition system over a battery Ignition system for aircraft reciprocating engines? |
The magneto has its own source of electrical energy and is not dependent upon the battery. |
|
What is the function of the capacitor in a magneto? |
It minimizes arching at the breaker points and speeds up the collapse of the primary current when they open. |
|
What is a compensated magneto Cam and on what kind of engine is one used? |
It is a special Cam that has one lobe for each cylinder and is mounted on high performance radial engines. |
|
What is the significance of the numbers on the distributor of an aircraft magneto? |
They are the sparking order of the magneto. |
|
What happens in a magneto Ignition system when the Ignition switch is placed in the off position? |
The primary circuit is grounded. |
|
What is the basic difference between a low tension Magneto and a high tension magneto? |
A low tension system uses a transformer coil near the spark plugs to boost voltage, while the high tension system voltage is constant from the magnito to the spark plugs. |
|
What is the difference between a hot spark plug any cold spark plug? |
A hot spark plug has a long path where the heat has to travel, where a cold spark plug has a shorter distance to travel allowing for cooler operation. |
|
What is checked when a magneto is internally timed? |
Breaker point opening to E-gap position and distributor rotor position to direct high voltage to cylinder number one. |
|
In what position should the Ignition switch be placed when using a timing light on the magnetos? |
On both. |
|
What type of Ignition system is used on most turbine engines? |
High intensity, intermittent duty, capacitor discharge Ignition systems. |
|
What is the function of an impulse coupling? |
To spin the magnet at a high rotational speed to produce a hot and retarded spark for starting the engine. |
|
How many igniters are used in most turbine engines? |
2 |
|
What are 2 types of Ignition systems used in turbine engines? |
High voltage and low voltage systems. |
|
With which type of Ignition system is a glow plug igniter used? |
Low voltage system. |
|
What is an E gap angle? |
A few degrees beyond the neutral position of the rotating magnet where maximum magnetic fields stress exist. |
|
What malfunction in the Ignition system would cause an aircraft reciprocating engine to continue to run after the Ignition switch is placed in the off position. |
The primary circuit is not being grounded. |
|
What is a magneto timing light used for and what does it indicate? |
It is used for internal magneto timing and magneto to engine timing and indicates the exact moment the points open. |
|
Why are turbine engine igniters generally not susceptible to carbon fouling? |
The higher energy sparks they produce clean off any deposits. |
|
What are the 3 main components of a turbine engine Ignition system? |
Igniters, high tension leads and exciters |
|
What is done to ensure that each generator shares the load? |
The generators are paralleled |
|
Name the components of a high tension magneto system. |
Rotating magnet, soft iron core, and pole shoes. |
|
What function does a magneto perform? |
It produces the spark at the spark plug. |
|
Name the 3 main circuits of a high tension magneto system. |
Magnetic, primary, and secondary circuits. |
|
Why are dual magnetos used in the engine Ignition system? |
To improve combustion and provide redundancy. |
|
What are possible sources of low pressure air use for starting jet transport aircraft equipped with air turbine starters? |
A ground power unit, an on board APU, and compressor bleed air. |
|
Name the components of a direct cranking electric starter system. |
An electric motor, reduction gears, and an automatic engageing/disengaging mechanism. |
|
What kind of DC motor is commonly used for a reciprocating engine starter and why? |
A series wound motor because it has a high starting torque. |
|
What are the operating modes of a turbine engine starter generator? |
First as a starter then as a generator when the engine is running. |