Just for Kicks and Giggles

[earl1937]

  Almost all of the aircraft in Aces High needed some form of carburetor heat! In Aces High, this function is automatic so you don't have to worry about it! In engines with carburetors, there is a device called a "venturi" inside the carburetor. When the engine is running, there are (2), two events which occur, one is an increase in _______________and the second one is a decrease in ________________, resulting in the need for carburetor heat! Please fill in the blanks with your answers.
(FYI, there may be some in this game who are in training as a real life pilot, or maybe some who already are, but do not understand this function) This might could save someones life, guys, so bear me out on this!

[ImADot]

Not really wishlist forum material...

[MrKrabs]

Almost all of the aircraft in Aces High needed some form of carburetor heat! In Aces High, this function is automatic so you don't have to worry about it! In engines with carburetors, there is a device called a "venture" inside the carburetor. When the engine is running, there are (2), two events which occur, one is an increase in _______________and the second one is a decrease in ________________, resulting in the need for carburetor heat! Please fill in the blanks with your answers.
(FYI, there may be some in this game who are in training as a real life pilot, or maybe some who already are, but do not understand this function) This might could save someones life, guys, so bear me out on this!

I sense a thread moving in the near future...

[gyrene81]

isn't it "venturi" in the carbs, not "venture"?

Not really wishlist forum material...

and what he said...

[Arlo]

It'll all work itself out. I like Earl. 

[gyrene81]

i would venture to say that it will Arlo...

[Arlo]

i would venture to say that it will Arlo...

LOL   

[earl1937]

isn't it "venturi" in the carbs, not "venture"?

and what he said...

You air are correct! Just mark that up to fat finger stroke I guess, didn't even catch it when I reviewed before posting.

[earl1937]

Not really wishlist forum material...

I could not agree with you more, sir, but why not have a tab in the forums for "real" life aviation stuff? Bet it would get a lot of attention and use.

[ImADot]

I could not agree with you more, sir, but why not have a tab in the forums for "real" life aviation stuff? Bet it would get a lot of attention and use.

I think they already have one. "Aircraft and Vehicles" might fit the bill.
 

[Eric19]

Almost all of the aircraft in Aces High needed some form of carburetor heat! In Aces High, this function is automatic so you don't have to worry about it! In engines with carburetors, there is a device called a "venturi" inside the carburetor. When the engine is running, there are (2), two events which occur, one is an increase in air and the second one is a decrease in fuel, resulting in the need for carburetor heat! Please fill in the blanks with your answers.
(FYI, there may be some in this game who are in training as a real life pilot, or maybe some who already are, but do not understand this function) This might could save someones life, guys, so bear me out on this!

or the other way around I can't remember not even a pilot but it happens in all engines hell my 1980 Mirada basically has an aircraft engine in it

[perdue3]

Carb heat is to prevent or reduce the amount of ice build-up and for reduction in power. If you have an increase in RPM you know there is an ice build up. The ice melting frees up more space thus allowing more air to flow through. If you get sputtering or a few misses you know that water (melted ice) is in the engine and an increase in power follows. Thus you know you need more carb heat. When descending or on idle, more carb heat is needed as well.

It also obsoletes the air filter. In case it is dirty or stopped up, carb heat allows the engine to operate.

And it is venturi, not venture.

As far as fill in the blank goes: If you are specifically talking about the venturi it is an increase in fuel vapor to carburetor and decrease in pressure. But that is only what the venturi does. There are many things occuring when an engine is running. There are more than 2 reasons why you need carb heat. Thus, my long post.

[earl1937]

Carb heat is to prevent or reduce the amount of ice buildup and for reduction in power. If you have an increase in RPM you know there is an ice build up. The ice melting frees up more space thus allowing more air to flow through. If you get sputtering or a few misses you know that water (melted ice) is in the engine and an increase in power follows. Thus you know you need more carb heat. When descending or on idle, more carb heat is needed as well.

It also obsoletes the air filter. In case it is dirty or stopped up, carb heat allows the engine to operate.

And it is venturi, not venture.

As far as fill in the blank goes: If you are specifically talking about the venturi it is an increase in fuel vapor to carburetor and decrease in pressure. But that is only what the venturi does. There are many things occuring when an engine is running. There are more than 2 reasons why you need carb heat. Thus, my long post.

Pretty good answer, but the correct answer to the question is this: when you have an increase in air flow, caused by a "venture", you have an increase in velocity which results in a rapid drop in temperature, hence the need for some engines to have carb heat.

[colmbo]

Perdue,

Didn't you mean a decrease in RPM with carb ice present?

I'm not so sure about that "need more heat at idle" statement.  I understand it is the common belief and it has been a "fact" since forever in aviation.

I have gotten carb ice at takeoff power, at cruise power...but never at idle power (this all with a Cont O-470 in a Cessna 182).  I've had a complete loss of power just after takeoff in a Cessna 152 that was probably carb ice -- no other problem being found. (I got back to the runway).

When I put the new engine in the 182 I also installed a 14 channel engine analyzer, one of those channels being used for carb air temp.  Something interesting I noted was that the coldest temps were at times of high power.  Kind of makes sense, more air being pulled in, higher velocity of air, greater pressure reduction/temp reduction.  I also noticed that once the power was brought back far enough the RPM dropped (constant speed prop) the carb air temp would pretty much match ambient air temp.

I changed the way I used carb heat, no more prophylactic heat on with reduced power.  While still pulling some power on downwind heat on for a moment to clear any ice that may have formed then heat off once power reduced.  Monitor carb air temp and use heat only when ice indicated.  I was hauling jumpers at the time and did a few thousand landings operating that way and never had an issue with carb ice.

[icepac]

Columbo is correct.......escpecially if you have enough experience to notice it's affect and the time it takes to deice a carburetor in the plane you are flying.

I understand the manual recommending carb heat on whenever you pull your throttle or are in the pattern but I have also encountered it at full throttle.

It is very effective at deicing and only takes a few seconds.

That said, landing heavy at a high density altitude can possibly cause carb heat to lower your horsepower enough to cause a problem with a "Go-around" so be quick to push it back in if you suspect you might need more power.

The answers to the original question are "vacuum" and "temperature" but "vacuum" can often be referred to as pressure.........but less of it.