Chapter 5 Induction systems

What are the three components of the induction system of a reciprocating engine?

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

What could happen if the induction system becomes obstructed?

The engine may not be able to produce its rated power or may not run at all.

How does induction icing affect engine performance?

It causes a reduction in power and possible erratic operation.

How is induction icing categorized?

As impact ice, fuel evaporation ice, and throttle ice.

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

Raise the temperature of induction air with a preheater.

What causes fuel evaporation ice?

Fuel evaporation ice is formed due to the decrease in air temperature resulting from evaporation of the fuel after it is introduced into the air stream.

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

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

What may be the indication of leaking intake pipes?

The engine runs rough at low r.p.m.

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

There is a noticeable drop in power.

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

Detonation.

What are the two types of supercharged induction systems?

Internally driven and externally driven.

How does an internally driven supercharger boost air pressure?

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

What is used to power a turbocharger?

Engine exhaust gas directed onto the turbocharger turbine.

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

The engine may not be able to produce its rated power at certain altitudes.

What function does a turbocharger waste gate perform?

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

What could cause a turbocharged engine to surge?

A waste gate or controller malfunction.

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

Mechanically with linkages to the throttle or a separate control, or by an actuator driven by oil pressure.

What component in the turbocharger system limits the amount of turbocharger airflow used for cabin pressurization in a pressurized reciprocating aircraft?

The sonic venturi.

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

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

Where are bellmouth inlet ducts typically found?

On helicopter engines.

How do venturi-type particle separators function in turbine powered helicopters?

A venturi accelerates the flow of incoming air and debris through a curved intake, channeling debris away from the compressor.

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

Engine bleed air and electric heating elements.