Reciprocating Engine Induction and Cooling Systems Flashcards
What does a fuel-injected engine have that prevents the loss of induction air if the air inlet filter should become covered with ice?
An alternative air valve allows warm air from inside the engine cowling to flow into the fuel metering system.
What would be the effect on engine operation of an air leak in the intake pipe for one cylinder?
That cylinder would run lean and detonation could occur.
What must be inspected on the cooling system of an air-cooled engine?
All of the baffles and air seals must be in place and in good condition.
Why should an air-cooled engine not be run up to high power without the cowling installed?
The engine depends on the cowling to force air through the cylinder fins to remove the excess heat.
Why do some air-cooled engine installations have cowl flaps?
cowl flaps produce a low pressure on one side of the engine to pull air through the cooling fins on the cylinder.
What document describes the proper use of cowl flaps on an air-cooled engine?
The pilot’s operating handbook.
Why does ice form in the throat of a float carburetor?
when liquid fuel evaporates it absorbs enough heat from the air to cause moisture to condense out and freeze.
Are internally driven superchargers located before or after the carburetor?
Internally driven superchargers compress the air-fuel mixture after it leaves the carburetor, while externally driven superchargers (turbochargers) compress the air before it is mixed with the metered fuel from the carburetor.
What are the three main parts of a typical turbosupercharger?
-Compressor assembly
-Turbine wheel assembly
-Full floating shaft bearing assembly
How is a turbocharger driven?
Externally driven supercharges derive their power from the energy of engine exhaust gases directed against a turbine that drives an impeller that compresses the incoming air.
How is a supercharger driven?
The supercharger id directly driven from the engine and is internal to the engine.
how does an augmentor system increase cooling airflow over a reciprocating engine?
Augmentors use exhaust gas velocity to cause airflow over the engine so that cooling is not entirely dependent on the prop wash.
Why is it very important that the induction air filters be kept clean and replaced as often as the manufacturer recommends?
Clogged air filters can restrict the air entering the engine.
Does the application of carburetor heat cause the fuel-air mixture to become richer or leaner?
The less dense, heated air draws the same amount of fuel from the carburetor as cold air; therefor the mixture becomes richer.
What happens to engine RPM when carburetor heat is applied?
The RPM drops.
Why should the use of carburetor heat be limited when operating an engine with aircraft on the ground?
The air that flows into the engine when carburetor heat is applied is not filtered.
Why is a fuel-injected reciprocating engine not as prone to icing as an engine equipped with a float carburetor?
In a fuel-injected engine, the liquid evaporates in the intake valve chamber of the hot cylinder head. In a carbureted engine, as air flows through the carburetor venturi, the pressure drops, decreasing temperature and increasing the chance of icing.
What creates the pressure of the air in a pressure cowling?
The forward velocity of the airplane as air enters openings in the cowling and flows into the engine compartment.
What is meant by pressure cooling of an air-cooled engine?
Ram air on one side of the engine is forced by a series of baffles to flow through the fins on the cylinders to a low-pressure area on the other side of the engine.
What controls the amount of air cooling in a pressure cowling system?
The exit air is controlled through the use of cowl flaps. The cowl flaps are opened to allow more airflow and more cooling. The cowl flaps are closed to reduce the amount of airflow over the engine.
What is the purpose of engine baffles and seals in a pressure cowling system?
The baffles and seals cause the air to be directed over the cooling fins on the cylinders.
Where can you find what is the maximum amount of cylinder fin area that can be removed in order to clean out a damaged area?
In the engine overhaul manual.
How is heat removed from the liquid in a liquid-cooled engine?
By flowing air over a radiator.
