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Redroach
05-28-2011, 12:05 AM
I want to discuss about this one.
I've flown fighters almost exclusively so far, and, based on my crude, limited experience, I won't cry out "Bug!", but I think some chat about mixture would surely be warranted.

So, has anyone found some plane/alt/throttle setting where lean mixture is actually flyable (that is, with the engine running smoothly and probably fuel-saving)? I've yet to encounter such a situation. Surely, Messerschmitt's mixture is set automatically, so something could go on there behind the curtain, but I've definately not been able to use lean mixture successfully with RAF fighters.
And, as stated, I'm not into bombers yet.

Has someone made better/different experiences? Or should it even be that way?

P.S.: General rants a la "the whole FM is corrupted" are of little help here only :)

IvanK
05-28-2011, 12:39 AM
RAF fighters (and Blenheim) mixtures are Auto Lean and Auto Rich. No other adjustment required. Once selected you are running in either an automatic altitude compensated LEAN or RICH mixture thats all there is to it.

Ze-Jamz
05-28-2011, 12:43 AM
I notice it changes the colour from red/orange to Blueish when adjusted in the british fighters..cant say ive noticed anything else with that setting

Viper2000
05-28-2011, 01:11 AM
RAF fighters (and Blenheim) mixtures are Auto Lean and Auto Rich. No other adjustment required. Once selected you should be running in either an automatic altitude compensated LEAN or RICH mixture that's all there is to it.

FTFY

At present (latest patch, tested just now), switching to lean mixture at high altitude makes the engine run rough to the point that the prop governor on a Spitfire IIa won't hold rpm properly. It doesn't break the engine, but it's clearly unhappy.

OTOH, at least I was able to climb to FL200 "full switch" without breaking anything, so that's progress.

Redroach
05-28-2011, 03:18 AM
RAF fighters (and Blenheim) mixtures are Auto Lean and Auto Rich. No other adjustment required. Once selected you are running in either an automatic altitude compensated LEAN or RICH mixture thats all there is to it.

sorry if I've expressed myself wrongly, but that wasn't the point of my question(s). Viper's got the point, though (I think).

So it seems that for the RAF, there are close to zero useful 'lean mixtures'. What about the Luftwaffe? Does anyone know or does anybody fly a lean mix at altitude; i.e. a non-forced one?

edit: Oh, @ze-jamz: When you were adjusting your mix to blue-ish exhaust flames, did that make your engine/plane shake or vibrate? Which plane did you fly anyways?

Skoshi Tiger
05-28-2011, 04:00 AM
It seams to work well in the Spitfire IIa, following the manual settings for maximum range.

Air Speed 160 mph IAS, Mixture weak.

I found I was setting the govenor to about 2400RPM and then using the throtle to maintain about 2200- 2300rpm. I was trying to keep my manifold pressure as low as possible.

When I tried in a MK1a I found that my rpm was bouncing around a lot under 2400rpm and I found it difficult to maintain airspeed.

Cheers

whoarmongar
05-28-2011, 05:59 AM
You mean your mix actually works in the spit ? I fly the spit 1a and on start it will fire up on either lean or rich, but runs better ie revs pick up on lean !
When actually flying I use lean at all times as it will never run right on rich.
By lean i mean lever forward,
I just thought it was a bug.

Skoshi Tiger
05-28-2011, 07:48 AM
You mean your mix actually works in the spit ? I fly the spit 1a and on start it will fire up on either lean or rich, but runs better ie revs pick up on lean !
When actually flying I use lean at all times as it will never run right on rich.
By lean i mean lever forward,
I just thought it was a bug.

When flying the Spitfire IIa under the conditions stated above it seams to work ok for me. Running the MkIa under similar conditions has issues.


http://spitfiresite.com/wp-content/uploads/2010/07/03it_001.jpg

One thing I just noticed testing (just now) is the interlocking device doesn't seam to work in the IIA? I'm sure it did before.

Cheers!

jf1981
05-28-2011, 11:18 AM
Hi Redroach,

Thanks for that interesting thread, I'm sure we'll find interesting answers in here.

So nothing wrong with being ignorant, you may find that in nearly all of my threads, I then had time to discuss & make measurements & investigates on the topic. It's all right naturally.

Redroach
05-28-2011, 01:59 PM
well, I HAVE the manual right here, you know? So, conditions for lean mixture flight are known to me, at least for the fighters. And that's where the confusion starts: It doesn't seem to be that way ingame. No issue here due to lack of reading, sorry. Or maybe there is? If you would be so kind, please point me to a thread where FM issues (not lack of knowledge when it SHOULD be lean mixture - I'm aware of that). about Mixture are explained.
I'd still suggest you do some reading before throwing yourself into the fray.
If you've posted RL-Gliding ratio for the He111, compared with your test results, we could have had an enlightening discussion back then, instead of me being crazy about you cooking up issues which could probably upset the develeopers (Merlin g-cutouts and the likes come to my mind...).
Besides that, I've even found the subforum, so nothing new here for you to exploit, I'm afraid.

P.S.: You lay in wait for that, didn't you? Cool! :cool:

Back OT:
To reformulate my issue into another question:
Do I actually have to assign keybindings for setting mixture? Or could I get along without even bothering in CoD?

jf1981
05-28-2011, 04:06 PM
Hi,

I made similar observations. This deserves some tests (I may do & post back in this thread later). I prefer from far the soft (or should I say lean) Redroach to the coarse one so to say.

Regards

Ze-Jamz
05-28-2011, 04:10 PM
sorry if I've expressed myself wrongly, but that wasn't the point of my question(s). Viper's got the point, though (I think).

So it seems that for the RAF, there are close to zero useful 'lean mixtures'. What about the Luftwaffe? Does anyone know or does anybody fly a lean mix at altitude; i.e. a non-forced one?

edit: Oh, @ze-jamz: When you were adjusting your mix to blue-ish exhaust flames, did that make your engine/plane shake or vibrate? Which plane did you fly anyways?

Hi Red sry mate just seen that post..

No it didnt make any difference to the performance etc nor did it make the plane shake which is strange...anyway it was boht the Hurri and SpitIa

RE77ACTION
05-28-2011, 05:55 PM
I think the mixture thing isn't worked out very well in this game. My real world experiences with changing mixtures are the following and I don't see it represented in CloD:

Lean mixture should give less power but more RPM. It also should run a lot hotter because of various reasons.

Rich mixture should give more power in lower RPM but lacks the ability give as much RPM as with a lean mixture. Rich mixture should also spill some fuel to the exhaust system.

I hope they will take care of it in future updates.

Skoshi Tiger
05-29-2011, 01:03 AM
I think the mixture thing isn't worked out very well in this game. My real world experiences with changing mixtures are the following and I don't see it represented in CloD:

Lean mixture should give less power but more RPM. It also should run a lot hotter because of various reasons.

Rich mixture should give more power in lower RPM but lacks the ability give as much RPM as with a lean mixture. Rich mixture should also spill some fuel to the exhaust system.

I hope they will take care of it in future updates.

I also think that there are issues with the mixture system in the game. From my flying days (It's beenmany moons since I actually got in the left hand seat of a plane) Most of the time you want the mixture in the rich position.

When you are flying with a rich mixture you have excess fuel in your fuel air mix. As you lean out your mixture, lets say for a cruise, your reducing the ammount of fuel in the mix.

The closer you get to a chemically perfect mixture the more efficient the combustion process is and you will find that your RPM, combustion chamber temperature and power increases. This is good except that as you get closer to the chemically correct ratio of fuel and air the chance of pre-ignition and detonation also increases.

Pre-ignition is when the fuel air mix spontainiously ignites befor the spark plug fires and leads to rough running. Detonation being when the fuel air mix in the combustion chamber explodes instead of burns in a controlled manner. Detonation causes rough running and can damage the engine.

When leaning for the cruise in the cessna the procedure (if I remember correctly) was to lean the mixture until you find your maximum RPM (close to the chemically correct ratio) and then push the mixture in a bit to give a richer but safer mixture. Nearly all the other checks I remember were to put the mixture in the rich position (less efficient but less chance of damaging the engine)

In the Spitfires in COD we only have a two settings, Rich and Weak. Unless your flying for maxium range the manual tells us to make sure the mixture is in the Rich (rear) position.

I guess this is for safety. In COD I haven't had a mission that I've had to worry too much about fuel yet. This is probably a major issue for the boys in the 109's trying to get a few extra minutes over London.

I think I'm safe in saying we all want the mixture system in the game to be working in an historically correct and accurate fashion for all aircaft modeled in the game.

Cheers!

Blackdog_kt
05-30-2011, 04:04 AM
Generally speaking, lean is used to save fuel during cruise at lower boost/RPM.

Even in late war hotrods like the P47, pilots are advised to run auto-rich in combat to help the engine take the higher manifold pressure and RPM values with less chance of overheating and all the other problems mentioned by previous posters.

Also, there are cases when chopping the throttle might lead to fuel starvation, which is why the mixture lever is backwards in the RAF planes to make it compatible with the inter-locking pins: you chop the throttle and it pulls the mixture lever back into rich so you don't have to think about it.

Long story short, lean is for fuel economy when moving along at a leisurely pace, not for use during combat ;)

The luftie birds usually don't have mixture controls, definitely not the 109/110 and if i'm not mistaken, the 88,Stuka and 111 also lack them, so i guess they are all automatic.

TomcatViP
06-12-2011, 11:11 AM
The luftie birds usually don't have mixture controls, definitely not the 109/110 and if i'm not mistaken, the 88,Stuka and 111 also lack them, so i guess they are all automatic.

They are indeed. Thx to the integrated dev system they bring in when they had to rebuilt their aircraft industry.

Full automation in eng ctrl came indeed first with the 190 so let's say 1941/42. A FADEC alike but with no Digital and Electronics inside :rolleyes: