Flashcards in Powerplant Chapter 5 FAA ORAL questions - Induction Systems Deck (22):
Name the three components on 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 it may not run at all. This may also be an indication of a dirty air filter.
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, 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 because of the decrease in air temperature resulting from evaporation of the fuel after it is introduced into the airstream.
Is carburetor throttle ice more likely to occur at higher or lower settings? Why?
At lower power settings 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 noticable drop in power
What could happen if carburetor heat is applied at high engine power settings?
What are two types of supercharged induction systems?
INternally and externally driven
How and at what point 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 happen if the waste gate on a turbocharger system does not fully close?
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
What function does a turbocharger waste gate perform?
It controls the amount og gas either into or around the turbocharger, thus controlling the boot pressure of the turbocharger.
What could cause a turbocharged engine to surge?
There could be a waste gate or controller malfuction
What are the most common ways to control a waste gate?
Either mechanically with linkages to the throttle or a seperate control, or by an actuator that is driven by oil pressure
In a pressurized reciprocating aircraft, what components in the turbocharger system is used to limit the amount of turbocharger airflow used for cabin pressurization?
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 seperators, found on many turbine powered helicopters, function?
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.