Powerplant Oral Ignition And Starting Systems

Front 1

What is the main advantage of a Magneto Ignition system over a battery Ignition system for aircraft reciprocating engines?

Back 1

The magneto has its own source of electrical energy and is not dependent upon the battery.

Front 2

What is the function of the capacitor in a magneto?

Back 2

It minimizes arching at the breaker points and speeds up the collapse of the primary current when they open.

Front 3

What is a compensated magneto Cam and on what kind of engine is one used?

Back 3

It is a special Cam that has one lobe for each cylinder and is mounted on high performance radial engines.

Front 4

What is the significance of the numbers on the distributor of an aircraft magneto?

Back 4

They are the sparking order of the magneto.

Front 5

What happens in a magneto Ignition system when the Ignition switch is placed in the off position?

Back 5

The primary circuit is grounded.

Front 6

What is the basic difference between a low tension Magneto and a high tension magneto?

Back 6

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.

Front 7

What is the difference between a hot spark plug any cold spark plug?

Back 7

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.

Front 8

What is checked when a magneto is internally timed?

Back 8

Breaker point opening to E-gap position and distributor rotor position to direct high voltage to cylinder number one.

Front 9

In what position should the Ignition switch be placed when using a timing light on the magnetos?

Back 9

On both.

Front 10

What type of Ignition system is used on most turbine engines?

Back 10

High intensity, intermittent duty, capacitor discharge Ignition systems.

Front 11

What is the function of an impulse coupling?

Back 11

To spin the magnet at a high rotational speed to produce a hot and retarded spark for starting the engine.

Front 12

How many igniters are used in most turbine engines?

Back 12

2

Front 13

What are 2 types of Ignition systems used in turbine engines?

Back 13

High voltage and low voltage systems.

Front 14

With which type of Ignition system is a glow plug igniter used?

Back 14

Low voltage system.

Front 15

What is an E gap angle?

Back 15

A few degrees beyond the neutral position of the rotating magnet where maximum magnetic fields stress exist.

Front 16

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.

Back 16

The primary circuit is not being grounded.

Front 17

What is a magneto timing light used for and what does it indicate?

Back 17

It is used for internal magneto timing and magneto to engine timing and indicates the exact moment the points open.

Front 18

Why are turbine engine igniters generally not susceptible to carbon fouling?

Back 18

The higher energy sparks they produce clean off any deposits.

Front 19

What are the 3 main components of a turbine engine Ignition system?

Back 19

Igniters, high tension leads and exciters

Front 20

What is done to ensure that each generator shares the load?

Back 20

The generators are paralleled

Front 21

Name the components of a high tension magneto system.

Back 21

Rotating magnet, soft iron core, and pole shoes.

Front 22

What function does a magneto perform?

Back 22

It produces the spark at the spark plug.

Front 23

Name the 3 main circuits of a high tension magneto system.

Back 23

Magnetic, primary, and secondary circuits.

Front 24

Why are dual magnetos used in the engine Ignition system?

Back 24

To improve combustion and provide redundancy.

Front 25

What are possible sources of low pressure air use for starting jet transport aircraft equipped with air turbine starters?

Back 25

A ground power unit, an on board APU, and compressor bleed air.

Front 26

Name the components of a direct cranking electric starter system.

Back 26

An electric motor, reduction gears, and an automatic engageing/disengaging mechanism.

Front 27

What kind of DC motor is commonly used for a reciprocating engine starter and why?

Back 27

A series wound motor because it has a high starting torque.

Front 28

What are the operating modes of a turbine engine starter generator?

Back 28

First as a starter then as a generator when the engine is running.