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Noxx0s
06-06-2010, 10:09 AM
I searched and there's a bunch of threads but most have to do with the hurri.

I'm asking for the yak and lagg. At what altitudes do I use which mixtures? Thanks.

TinyTim
06-06-2010, 10:25 AM
At low altitudes use 100% (this is the default misture setting when you spawn, regardless of the altitude). When climbing, you don't need to know exactly when to change mixture - at certain altitude your engine will start loosing power and emitting brown smoke trail due to mixture being to rich - it is then time to reduce the mixture. Repeat when happens again at higher altitude.

Noxx0s
06-06-2010, 11:00 AM
Wwhat about the 120%?

Zeus-cat
06-06-2010, 11:37 AM
I've used 120% to get extra power at low altitudes. It does heat up the engine faster so I only use it for things like takeoff from a carrier with a heavy load. You could use it for extra speed to shake an enemy from your tail, but since it heats up the engine faster you better get away quickly or you will pay for it.

TinyTim
06-06-2010, 11:45 AM
Originally posted by Zeus-cat:
You could use it for extra speed

I have tested this on a couple of planes and it didn't increase max. speed.

JtD
06-06-2010, 11:52 AM
From what I found you can set it to 80% on take off and leave it that way for all altitudes Yaks and LaGGs usually fly at with no ill effect.

Zeus-cat
06-06-2010, 06:04 PM
Originally posted by TinyTim:
I have tested this on a couple of planes and it didn't increase max. speed.

Very interesting. I never tested it myself; I just assumed...

WTE_Galway
06-06-2010, 07:32 PM
My understanding is 120% mixture IRL provides ...
- combined with priming, easier starting in very cold conditions
(not relevant in game everything just fires up first go as if they were turbines)
- additional engine cooling possibly useful when taxi-ing unsure on this one
(probably not modelled in game, never tested it)
- an additional safety factor when taking off and landing as over-lean engines cause engine failure
(also probably not modelled in game)


My hunch is the 120% setting is there for historical correctness but probably does little or nothing in game. It may potentially let the engine run a little cooler in game but I have never tested this.

BM357_Sniper
06-07-2010, 02:06 AM
Originally posted by Zeus-cat:
I've used 120% to get extra power at low altitudes. It does heat up the engine faster so I only use it for things like takeoff from a carrier with a heavy load. You could use it for extra speed to shake an enemy from your tail, but since it heats up the engine faster you better get away quickly or you will pay for it.

In reality more fuel should provide a cooler engine. I have yet to have an engine overheat because of a higher mixture setting. Yours most likely overheated because of the WEP setting.

ytareh
06-07-2010, 04:17 AM
Has anyone REALLY done proper testing on this ?Would be very interesting As rule of thumb I think I change to 80% at 2.5km and 60% at 5km ...maybe 40% at 7.5-8km .Theres no doubt that the optimal alts vary with planes ....La5s definitely seem to prefer waiting till closer to 3km for supercharger and maybe 80% mix too...Im sure if smoke is showing its (way ) too late ...

120% mix REALLY any use ?-or just a red herring like 'magnetoes'?

julian265
06-07-2010, 05:40 AM
FWIW I've read that reducing mixture has no effect on fuel efficiency in Il-2, regardless of altitude.

rfxcasey
06-07-2010, 05:40 AM
I was thinking about this same thing just the other day. Now I feel I must test it. I'm guessing that you should see a performance. At higher altitudes the air is less dense and hence NOT changing your takeoff setting (100%) will yield a rich condition meaning you have too much fuel per volume of oxygen in your cylinders. Having a rich condition will not provide optimal performance in real life. Now how this works in IL-2 I don't know but aim to find out.

Erkki_M
06-07-2010, 05:43 AM
Originally posted by julian265:
FWIW I've read that reducing mixture has no effect on fuel efficiency in Il-2, regardless of altitude.

Whoever wrote that, was wrong. Use full power and RPM, and lower the mixture from 100% to 40 or 20, and see what happens.

Having flown nothing but Russian crates for 3 years(not the 3 last years though), I can say the mixture is very important, one easily lowers it too low and doesnt get full out of his aircraft.

EDIT, the required mixture and supercharger stage depends on the engine your Soviet crate has.

LaGG-3 s4, s29, s35 and Jak-1, Jak-7A, Jak-7B are one group,
LaGG-3 s66, Jak-1B, Jak-7BPF, Jak-9 series(Except U and UT), Jak-3
Jak-9U, UT, Jak-3 VK107
La-5
La-5F, FN
La-7

For the two first, supercharger stage change altitude is about 2400m. Mixture 80% alt is roughly 2900. I might remember them wrong by a few hundred meters, though, lower mix when the brown exhaust fumes appear, and keep trying the supercharger(eyes on manifold pressure).

K_Freddie
06-07-2010, 09:48 AM
Keep an eye on your manifold pressure http://forums.ubi.com/groupee_common/emoticons/icon_wink.gif