Induction Systems

Question 1

Name the three components of the induction system of a reciprocating engine:

Answer 1

The air scoop.
Carburetor or fuel control.
The intake manifold.

Question 2

What could happen if the induction system becomes obstructed?

Answer 2

Engine may not be able to produce it’s rated power or run at all.

Question 3

How does induction icing affect engine performance?

Answer 3

It causes a reduction in power and possible erratic operation.

Question 4

How is induction icing categorized?

Answer 4

Impact ice.
Fuel evaporation ice.
Throttle ice.

Question 5

What is the common method used to prevent induction system ice in a reciprocating engine?

Answer 5

Raise the temperature of induction air with a pre-heater.

Question 6

What causes fuel evaporation ice?

Answer 6

The decrease in air temperature resulting from evaporation of the fuel, after it is introduced into the air system.

Question 7

Is carburetor throttle ice more likely to occur at a higher or lower power setting? Why?

Answer 7

At a lower power setting, because the throttle is partly closed, offering a larger surface area for ice accumulation.

Question 8

What may be an indication of leaking intake pipes?

Answer 8

The engine runs rough at low RPMs.

Question 9

What happens to engine power when the carburetor heat is applied?

Answer 9

There is a noticeable drop in power.

Question 10

What could happen if carburetor heat is applied at high engine power settings?

Answer 10

Detonation.

Question 11

What are two types of supercharged induction systems?

Answer 11

Internally driven.
Externally driven.

Question 12

How and at what point does an internally driven supercharger boost air pressure?

Answer 12

An engine driven impeller compresses the fuel air mixture after it leaves the carburetor.

Question 13

What is used to power a turbo charger?

Answer 13

Engine exhaust gas directed onto the turbo charger turbine.

Question 14

What could result if the wastegate on a turbo charger system does not fully close?

Answer 14

The engine may not be able to produce it’s rated power at certain altitudes, and the aircraft may not be capable of reaching critical altitude.

Question 15

What function does a Turbocharger wastegate perform?

Answer 15

It controls the amount of exhaust gas either into or around the turbo charger.

Question 16

What could cause a turbo charged engine to surge?

Answer 16

A waste gate or controller malfunction.

Question 17

What are the most common ways to control the waste gate?

Answer 17

Either mechanically with linkages to the throttle or a separate control, or by an actuator that is driven by oil pressure.

Question 18

In a pressurized reciprocating aircraft what component in the Turbocharger system is used to limit the amount of Turbocharger airflow used for cabin pressurization?

Answer 18

The sonic Venturi.

Question 19

What is the function of a divergent shaped jet engine inlet during subsonic flight?

Answer 19

It causes the air velocity to decrease with a subsequent increase in air pressure.

Question 20

Where are bellmouth inlet ducts typically found?

Answer 20

On helicopter engines.

Question 21

How do Venturi-type particle separators found on many turbine powered helicopters function?

Answer 21

A Venturi is used to accelerate the flow of incoming air and debris through a curved intake. The debris gains too much inertia to allow it to follow the curved intake towards the engine.

Question 22

What are the most common methods used for anti-icing of turbine engine inlet ducts?

Answer 22

Engine bleed air.
Electric heating elements.