Optimizing flight/speed with CEM

[prophet106]

It's thin white puffs. Not smoke per-se (there's no trail behind the aircraft). I get it from the moment i take-off to the moment i land so it can't be overheating. I normally fly with water temp at about 90-100. It's annoying knowing i can squeeze more speed from my crate but don't know how

Perhaps i can find out how to video it and upload/post it ?

[Blackdog_kt]

Try going to an external view (enable them in your difficulty settings if you need to) and making an attempt to identify the point from where the puffs originate.

I haven't spent much time in the RAF fighters except for some Hurricane sorties, but if you could tell us where the puffs of smoke appear on the airframe we might be able to give you a few more hints.

The effect you describe however is similar to a busted radiator: if you let the temps rise too much the pressure in the lines gets higher as well and it can break the pipes. When that happens, you can see white/grey puffs of steam coming out of the radiator.

Another thing which i'm not sure if its modeled in the sim is the escape valve. In the real world Spitfire there was an escape valve ahead and to the right of the windscreen, when the coolant would overheat some of it would be blown out of that valve to lessen the pressure and prevent damage to the pipes. This allowed pilots to "ride the overheat" so to speak for a small amount of time, at the expense of depleting their available coolant supply.

[Jatta Raso]

i got the hang of it like this:

take off:
fine pitch
radiator 50-70% (what takes not to reach 100ºC)
engine 20%
->fire engine
warm up (do your check list in the meantime)
->engine to 30-40% (start moving, watch the temps and adjust rads accordingly)
->if no engine stuttering: step on it

airborne
using your throttle (but not bellow 80%) and climb angle to keep the revs bellow 2800rpm, start a shallow climb until 1000m; go in steps if you have to; always trim to get just your intended angle; don't wait for the stall to interrupt the climb, anticipate that

once at 1000m trim for level flight, attain your max speed (by now i close my rad about to 70-80%, always watching)

climb to 2000m using same process

once at 2000m trim for level flight, attain your max speed

start a shallow dive and change to coarse; your revs should jump to near 2100rpm
->throttle to max; use the small speed gain of the dive to help the spinner pick up revs
once at 1600m you should have at least near 2300rpm which is by now a stable engine operation, that allows for an efficient rev pick up; at coarse pitch you must not fall bellow 2100rpm or you may need to go back to fine pitch

start a gentle climb as you should have enough speed for such
climb to 3000m
once at 3000m trim for level flight, attain your max speed; you should be hitting the 2500rpm soon which is the optimal situation you're seeking

if serious trouble persists, maybe i can drop a vid of it...

[pwgee]

Here are my thoughts

Firstly, I understand that this sim is far from flawless.

Secondly, this post is coming from a professional aviator with 20+ years of experience.

If things were modeled and coded as they should be I can tell you that this is the way the sim should operate.

For startup:
Fuel cock on (obviously)
Magnetos ned to be both on, 1+2, the magnetos give the engine the fire it needs to combust the gas and air, these old planes did not have spark plugs. The magnetos keep the engine burning the combustible properly.

Mixture should be full rich, at sea level or close to there anyway, since we are not taking off from a field elevation of 5000ft there is no reason to lean the mixture until we climb to altitude, again I dont think this is modeled correctly in game; I have treid leaning the mixture at 3000m to try and get better performance, but it doesnt seem to do s@$% until u lean it off to the cut-out point.

The prop should be full forward or full fine, it doesnt really matter since the engine is just at idle power anyway. It really wont change prop RPM until you add mucho power (i.e. when u dive in a 109 or 110 u notice you have to pull the props back to avoid over-revving).

Radiators for start should be full open since you are not flying through the air generating any ram air flow to cool them. It doesnt matter too much until the oil warms up to take off temperature anyway.

Crack the throttle and hit the starter.


Climb:

For a real world climb you should climb at max prop for maximum thrust and best climb rate. Watch your oil and water temps and level out for a few minutes to cool them down if you have to. Leveling out SHOULD cool them down as you have more airflow going over the cooling fins.

Manifold/Boost pressure, climb at max until cruise or until you are limited by coolant temperatures.

Cruise:

pull the props back a bit to stay out of the red zone on the RPM gauges, you will hear the prop chage speeds especially in the 110's.

pull the Manifold/boost gauges back to saty out of the red zones.

Just watch your temperatures, close or open the radiators to keep a mid range temp.

Combat:

Full props and full throttle, radiators wide open. The only difference is the 109's and 110's. These props are fully manual and you will burn out the engines in less than a minute if you dont constantly change the prop pitch in dives and you will get crappy climb performance if you dont climb at full fine prop pitch. There is a relationship between aircraft speed and prop speed. You will notice that you cant develop maximum PROPELLER rpm until the airplane is flying fast enough to allow it ( as at roation from the runway), You will also notice that if you are flying too fast for your selected prop setting that you will over rev the prop ( as in a dive).

Basically you can run the props at full fine the entire flight as long as you dont go too fast, this is why we have a controllable propeller.

Also note this, the Spits and Hurris have Carburetters and are not fuel injected as the german planes are, what this means is that if you perfrom ANY negative G maneuver you will get an engine that struggles to stay alive, this may be the white or black smoke that you see, depending on altitude; IF the game is modeled correctly.

Another thing that is pretty cool in this game that I have seen is when you are in a Spit or a Hurri and you make a rapid throttle change you will see a puff of black smoke from the stacks; the carburettors have to deal with the rapid fuel input or rapid fuel starvation and you get mass burnoff of fuel or mass burnoff of air, pretty cool. The rest of the engine modeling could use some work.

The game is really good and have every confidence that it will get better with time just like the first days of IL2 2001.

Hope this helps

[aus3620]

Some excellent advice here. Mainly fly the Hurri at the moment. When I started CEM my flight would often leave me miles behind! I found the key is not to climb immediately after take-off but to build up speed, then climb out. Keep an eye on your speed when climbing and don't let it get below 150mph.

After leveling out go-to fine pitch. I find on fine pitch the engine seems to prefer full-rich, when I lean out it does not run as well.

CEM is the way to go.

Good luck with it,

[whoarmongar]

Ahem...


"Magnetos ned to be both on, 1+2, the magnetos give the engine the fire it needs to combust the gas and air, these old planes did not have spark plugs. The magnetos keep the engine burning the combustible properly."

They most certainly do have spark plugs, "clearing the plugs" was regularly done before engine shutdown on many aircraft.

Magnetos are used to generate current.

[pwgee]

I stand corrected, thank you whoarmongar. Yes the mags were/are for generating the electricity for the spark plugs.