1. 409.04 - Exhaust, Electrical, and Ignition.
Aero Engines
Exhaust, Electrical, and Ignition.

2. Review What are the names of the 4 strokes?
What are two different ways to cool an engine?
What are the four functions of oil?
What are the two types of fuel systems?
What type of gas is normally used in light aircraft?
What is the difference between detonation and pre-ignition?

3. Review
What is this?

4. Review
What is carburetor icing and when does it form?

5. Exhaust System

6. Exhaust System
A scavenging system that collects and disposes of the hot noxious gases discharged by the engine. 6 6

7. Exhaust Systems
Exhaust gas and heat is used in the operation of other systems:
Cabin heat
Carb heat
Turbocharging
Cabin Heat Control
Defroster
To Rear Cabin
Muffler and Shroud
Air Inlet 7 7

8. Exhaust Systems – Carburetor Heat8 8

9. Exhaust Systems – Cabin Heat9 9

10. Exhaust Systems – Turbocharger10 10

11. Electrical System

12. Electrical System Provides electrical power for the aircraft
Starting the engine
Operating Flaps
Lights, Radios, Nav Equipment
System consists of components which
Generate Power
Regulate / Control Power
Store Power
Distribute Power 12

13. Electrical System
Light aeroplanes usually have a 14 or 28 volt DC electrical system
An alternator, or generator, is the primary source of electrical power
Most modern aeroplanes use an alternator
Advantage of an alternator over a generator is that it is lighter and it can produce sufficient current at low engine speeds 13 13

14. Alternator Produces AC which is converted into DC by diodes
Require a small voltage (3 volts)
Output is controlled by a voltage regulator
A over-voltage sensor protects the system from an over-voltage condition by failing the alternator 14 14

15. Alternator 15 15

16. Battery
Provides power for engine starting, initial excitation of the alternator, and as backup in case the alternator fails
In normal ops the alternator provides power to the electrical system and charges the battery
They have an amp-hour rating
14 amp-hour battery can provide:
14 amps for 1 hour
1 amp for 14 hours
7 amps for 2 hours, etc. 16 16

17. Electrical System Components
Master Switch
Pilot Operated switch
Connects the aircraft battery and alternator to the aircraft’s electrical system 17 17

18. Electrical System Components
Starter Motor
Electric motor powered by the battery provides engine rotation for starting 18

19. 19

20. Electrical System Components
Circuit Protection
Means of protecting equipment from damage in case of an electrical malfunction or overload
Fuses or Circuit Breakers 20

21. Ignition System

22. Magnetos and Spark plugs
Function of system is to ignite fuel/air mixture by supplying a spark.
Each spark plug gets power from a magneto.
Magnetos are essentially rotating magnets which induce a current using the rotation of the engine.