Carburator air controls not working?

Hello guys! I tried fiddling with the carburator controls and didn't seem to get it working. I loaded a mission with cold weather (ground attack instant action mission) and my carburator air temp gauge showed very cold values below 0, so I pushed back the ram air lever and left the hot air lever all the way forward. Strangely it didn't affect the temp at all, even after a while. So I wondered if the controls even worked at all and tried the opposite with ram air all the way forward and hot air all the way back. Once again carburator air temp didn't change.

I don't know maybe I am missing something here... Or the carburator system isn't modeled... Or it's just a bug.

The short answer is: The temperature sensor comes before the section where the air gets warmed up.

The sensor is near the air intake and measures the temperature of the incoming air. Cold air in general is absolutely no problem for the engine.

In normal conditions you should use the combination "RAM Air, Normal", the "HOT Air" option only works if used with "Unrammed, filtered Air". You won't need to activate this manually because the "HOT Air" activates by itself if needed.

Carburetor air is needed for the combustion in the engine and the effects of the levers are the following:

RAM Air:

The air flows directly in the scoop (it gets "rammed" into the scoop, imagine the aircraft grabbing all the air by flying into it), this is used in almost all cases.

Unrammed, filtered Air:

The front intake is somewhat closed and the air comes through intakes in the side, it also gets filtered. The air flow then obviously is much slower but the filters can stop ice or dust particles from entering the engine.

You would use this on ground (or in some special other conditions) to prevent dust and dirt from entering, once ready for takeoff you would use RAM AIR again. Because the air flow is slower the engine is less powerful in this setting as with RAM Air.

Normal Air (Temperature):

The normal setting for the temperature control, the air enters the desired intake with its normal outside temperature. In general the engine has no problem with cold air.

Hot Air:

This setting only works if Unrammed, filtered Air was set. It also automatically activates if the aircraft detects icing in the scoop. If activated hot air from the engine enters the scoop and warms the incoming air from outside up before it passes to the engine. The primary use is to melt ice particles in the air before they enter the engine. Note that the higher you are the lower is the chance of icing because of the low air density. Icing is possible between -15°C and +5°C, for other temperatures it is extremely unlikely that icing occurs. Do not use this setting if flying above 12,000ft since it may result in an overly lean fuel mixture. In general you won't need this control, only if flying low in a snowstorm maybe :D

Last a note on DCS:

The heating is modeled correctly but AFAIK icing is currently not modeled so by using the heat you currently only give up power for nothing.

Very good explanation thanks!!! everything looks clear to me now :)

The short answer is: The temperature sensor comes before the section where the air gets warmed up.

 

The sensor is near the air intake and measures the temperature of the incoming air. Cold air in general is absolutely no problem for the engine.

In normal conditions you should use the combination "RAM Air, Normal", the "HOT Air" option only works if used with "Unrammed, filtered Air". You won't need to activate this manually because the "HOT Air" activates by itself if needed.

 

 

Carburetor air is needed for the combustion in the engine and the effects of the levers are the following:

 

RAM Air:

The air flows directly in the scoop (it gets "rammed" into the scoop, imagine the aircraft grabbing all the air by flying into it), this is used in almost all cases.

 

Unrammed, filtered Air:

The front intake is somewhat closed and the air comes through intakes in the side, it also gets filtered. The air flow then obviously is much slower but the filters can stop ice or dust particles from entering the engine.

You would use this on ground (or in some special other conditions) to prevent dust and dirt from entering, once ready for takeoff you would use RAM AIR again. Because the air flow is slower the engine is less powerful in this setting as with RAM Air.

 

Normal Air (Temperature):

The normal setting for the temperature control, the air enters the desired intake with its normal outside temperature. In general the engine has no problem with cold air.

 

Hot Air:

This setting only works if Unrammed, filtered Air was set. It also automatically activates if the aircraft detects icing in the scoop. If activated hot air from the engine enters the scoop and warms the incoming air from outside up before it passes to the engine. The primary use is to melt ice particles in the air before they enter the engine. Note that the higher you are the lower is the chance of icing because of the low air density. Icing is possible between -15°C and +5°C, for other temperatures it is extremely unlikely that icing occurs. Do not use this setting if flying above 12,000ft since it may result in an overly lean fuel mixture. In general you won't need this control, only if flying low in a snowstorm maybe :D

 

 

 

Last a note on DCS:

The heating is modeled correctly but AFAIK icing is currently not modeled so by using the heat you currently only give up power for nothing.

Thanks for the detailed explanation.

Question, by default the leveler position are Hot, Unrammed. Would I change them to Rammed, Normal after startup?

Exactly.

Filtered is used if there is dust. Imagine moving the AC on an old dirt field.

Or if you are flying through a sandstorm.

Hot is used if you are flying in conditions where ice particle can built up, which is very rare though.

It may be possible if you are flying relatively low at some very cold place on earth.

In almost every flight you just use normal, rammed.

Using unrammed (filtered) while not needed will reduce engine power since you can't grab as much air as without filtering then.

But then there's a question of what adverse effects are actually simulated in DCS. Sand/dust ingestion and carb icing are not, so clickable filtering/temp levers in warbirds are something "nice to have" but no needed for anything gameplay-wise.

Not sure about power loss at high altitudes from "hot" setting, though. Something worth testing I guess.

Using 'Hot' at high altitudes usually makes no sense.

While it is colder up there, the possibilitiy of icing drastically reduces and quickly becomes impossible due to reduced pressure.

So you may need it only when flying relatively low in very cold conditions. Icing conditions are rarely met.

Be aware that you might lose engine power though.

I don't have the manual at hand atm, but IIRC, while on the ground you should be using filtered air ONLY. Only after reaching 50' AGL should you switch to rammed air.

On the ground you can be sucking in dust and insects, and I don't think you want to be blowing that crap into your engine.

While running your approach, about the time you lower your gear and flaps is when you switch to filtered air again; not because you need it right then, but because you don't need any unnecessary distractions while landing.

Yes, that is correct.

Ground ops are usually done with filtered air, exactly for that reason.

But as mentioned, dust, sand and insects are currently not modeled.