Powerplant Chapter 5 FAA ORAL questions - Induction Systems

Question 1

Name the three components on the induction system of a reciprocating engine.

Answer 1

The air scoop, carburetor or fuel control, and the intake manifold.

Question 2

What could happen if the induction system becomes obstructed?

Answer 2

The engine may not be able to produce its rated power or it may not run at all. This may also be an indication of a dirty air filter.

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

As impact ice, fuel evaporation, and 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 preheater

Question 6

What causes fuel evaporation ice?

Answer 6

Fuel evaporation ice is formed because of the decrease in air temperature resulting from evaporation of the fuel after it is introduced into the airstream.

Question 7

Is carburetor throttle ice more likely to occur at higher or lower settings? Why?

Answer 7

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

Question 8

What may be the indication of leaking intake pipes?

Answer 8

The engine runs rough at low r.p.m

Question 9

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

Answer 9

There is a noticable 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 and 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 turbocharger?

Answer 13

Engine exhaust gas directed onto the turbocharger turbine

Question 14

What could happen if the waste gate on a turbocharger system does not fully close?

Answer 14

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

Question 15

What function does a turbocharger waste gate perform?

Answer 15

It controls the amount og gas either into or around the turbocharger, thus controlling the boot pressure of the turbocharger.

Question 16

What could cause a turbocharged engine to surge?

Answer 16

There could be a waste gate or controller malfuction

Question 17

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

Answer 17

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

Question 18

In a pressurized reciprocating aircraft, what components 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 seperators, found on many turbine powered helicopters, function?

Answer 21

A venturi is used to acelerate 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, and is channeled away from the compressor.

Question 22

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

Answer 22

Engine bleed air and electric heating elements.