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Ace_Eloff
03-13-2005, 05:00 PM
Can anyone help me out here? I want to fly with complex engine management on (not because its more effective but because its more fun) but I don't know where to begin. How do I use prop and mixture controls? What do I need to know in order to properly change mixtures and prop pitch? Perhaps some of you know a site I can go to that explains how to use prop and mixture controls? Thanks all!

Jon E.

Ace_Eloff
03-13-2005, 05:00 PM
Can anyone help me out here? I want to fly with complex engine management on (not because its more effective but because its more fun) but I don't know where to begin. How do I use prop and mixture controls? What do I need to know in order to properly change mixtures and prop pitch? Perhaps some of you know a site I can go to that explains how to use prop and mixture controls? Thanks all!

Jon E.

civildog
03-13-2005, 05:01 PM
You can find scads of info on it all here:


http://people.ee.ethz.ch/~chapman/il2guide/cemguide/intro.htm

BaldieJr
03-13-2005, 05:05 PM
<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>Originally posted by Ace_Eloff:
I want to fly with complex engine management on (not because its more effective but because its more fun) but I don't know where to begin.
<HR></BLOCKQUOTE>

But how do you know if it is more fun?

Ace_Eloff
03-13-2005, 05:06 PM
Awsome! Thanks a lot http://forums.ubi.com/groupee_common/emoticons/icon_biggrin.gif.

Ace_Eloff
03-15-2005, 12:20 AM
Well, i've studied the whole guide on CEM you gave me, and i've started implementing what i've learned, but there is somthing supicious happening.

I seem to be able to stay within recommended rpm 95% of the time without having to change my prop. pitch. Is this normal? I do some pretty steep dives but by throttleing back I find I don't even need to reduce prop. pitch %.

Occasionally in an extended steep dive I need to throttle back and lower the pop. pitch % but most of Il2 FB dogfights occur within a fairly narrow range of altitude and thus, there are no real extended steep dives to speak of.

So I find myself mostly modifying prop. pitch to make more efficient use of the engine during cruise - then when transitioning from cruise to climb I somtimes need to increase prop. pitch % and throttle to maintain a more constant rpm. Is there somthing i'm not getting, or is prop. pitch not really somthing you need to change very often?



Also i've noticed that in the LaGG-3 1941 I can go through a turn without any sideslip requireing correction with rudder. I looked at the slip ball in the turn and bank indicator on the LaGG-3 1941 all through some pretty tight turns and nothing, the ball stayed center the whole time without any use of the rudder... anyone know anything about that?

F19_Ob
03-15-2005, 03:09 AM
The prop pitch works a bit differently depending on wich plane u fly because there are different systems.

The 109 engines are the ones quickly damaged by minor mistakes with the adjustment in manual mode and therefore should be left on auto exept for economycruise.
The germans recommended to use manual pitch on landings but the Finns seemingly disobeyed this rule after some damaged engines and flew on auto all the way.

Earlier there has been some discussion on the forum about the use and benefits of manual prop-pitch in combat, but mainly in the 109.
I haven't yet heard about any 109 pilot using manual prop pitch in dogfights, although I still investigate this and have got some help from researchers and people who have interviewed surviving 109 pilots (nothing yet but auto though).
(if anyone have info or tip on this plz PM me or post a link)

Atleast regarding the 109 From atleast F-model and up U can safely use the autosettings to be historically accurate. Still dont feel too sure if the E-models had auto-pitch function, although I have been told Both yes and no.

The Finns used the 109 like this:
1. Radiator fully opened while taxiing and take-off so u dont overheat.

2 after take-off set radiator to auto and leave it there for the rest of the flight. (adjust only in emergency)

3. Prop-pitch left on auto from start to landing. Set only to manual pitch if u cruise longer periods so u save fuel.

Sounds too simple? This is one reason why the 109 had such success and remained dangerous until the end. The autofunctions helped the pilots to concentrate on the important matters.
It was modern.

-----------------------------------------

Golodnikov gives some examples of a problem with a linked system in allied fighters:


"A. S. What about the propeller?

N. G. The P-40 had two types of propeller. With the electric propeller, the pitch was regulated by an electric motor, and with the mechanical propeller, conventionally with levers and rods. The electric propeller was automatic, with combined control by the throttle and pitch. The throttle quadrant had a rheostat and the movement of the lever automatically regulated the pitch. The Tomahawk had the electric propeller, while the latest Kittyhawks had mechanical propellers. Both types of propeller were reliable.

I did not fly with the mechanical propeller because by this time I had transitioned to the Cobra. Regarding the linked control I can say the following: sometimes this linked control was a hindrance.

A. S. Strange. German fighters had a system of linked control of throttle and pitch. In fact, this system was considered a great advantage of German fighters. The pilot was less distracted in combat.

N. G. So they say. Normally, pitch and throttle are coordinated in the following manner: more RPMsāā‚¬"reduce pitch. This is how the linked system worked. However, when we were trying to overtake the enemy in a dive or conversely to break away, for maximum acceleration we needed to increase RPMs sharply. Initially the propeller was loaded up and only later was pitch reduced. If in a dive, with the increase of RPMs the propeller pitch was reduced immediately, the propeller would begin to function as a brake. German aircraft were good in the dive. In a fighter with a linked throttle-pitch system in a dive we either fell back or he caught up to us. Therefore we always preferred a separated or de-linked system."
-------------------
The Golodnokov articles give some insight regarding I-16, hurricane, p40's, p39 and some others.
Read all 4 parts here:
http://lend-lease.airforce.ru/english/articles/golodnikov/part1.htm
------------------

There is a good site explaning the different propellers and pitch-systems but I cant find it at the moments....

A few thoughts....

Tully__
03-15-2005, 03:26 AM
<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>Originally posted by Ace_Eloff:
Well, i've studied the whole guide on CEM you gave me, and i've started implementing what i've learned, but there is somthing supicious happening.

I seem to be able to stay within recommended rpm 95% of the time without having to change my prop. pitch. Is this normal?.... <HR></BLOCKQUOTE>

If you're in an aircraft fitted with a "Constant Speed" propellor, yes. Most (all?) of the allied aircraft are so fitted. An article that includes some history and a brief description of the various types of propellor control can be read here. (http://www.avweb.com/news/columns/182082-1.html)

F19_Ob
03-15-2005, 03:54 AM
Thnks Tully that was one of the the sites I was looking for.

Ace_Eloff
03-15-2005, 09:55 AM
I don't know how to figure out if its a CSP prop, but I suspect the LaGG-3 1941 is a CSP?

Thanks for the tip, looks like my particular craft doesn't need a tonne of prop adjustment... somthing i'm not too clear on tho:

Is there any problem with reducing the throttle % well below the rpm %?

If you create a low throttle high rpm situation with the thottle and prop. pitch controls is there any realistic engine damage, or engine explosion modelled in Il2:FB? In PF?

How rigid are the highest recommended rpm settings? I suppose that depends on the craft, but in Il2:FB is engine damage from overspeeding the engine accurately modelled? In PF?

Thanks, also, from the CEM guide, I was lead to believe that mixture should basically stay 100% unless you're flying at altitude at which point you should lean the mixture (lower %) and 120% is somtimes used for take off and cooling the engine. There was also some talk about leaning the mixture to save fuel, and enriching it to cool the engine, is this basically the application for mixture?

Thanks all http://forums.ubi.com/groupee_common/emoticons/icon_smile.gif. The prop guide (http://www.avweb.com/news/columns/182082-1.html) you linked was very interesting, mostly the same info that was already present in the CEM guide tho.

ColoradoBBQ
03-15-2005, 11:05 AM
The only engine damage modelled is when you overheat your engine for too long. You don't get engine damage if you set the wrong prop pitch and throttle combination. Going over your combat RPM, using WEP constantly, 120% fuel, or closing radiator on liquid cooled engines would lead to overheating.

Ace_Eloff
03-15-2005, 11:46 AM
So the absolute only time i'm damaging my engine is when that "Engine: Overheat" HUD sign pops up?

ColoradoBBQ
03-15-2005, 12:41 PM
I'm not sure if you lose performance after an overheat but when you overheat that plane for too long, the engine will get damaged.

fireman196988
03-15-2005, 12:50 PM
ColoradoBBQ, Wrong. You can damage the engine in the Bf-109 easily if you over rev the engine by incorrectly using the manual prop. pitch and throttle settings.

Fireman

Ace_Eloff
03-15-2005, 12:55 PM
Ok, good to know then, i'll watch my rpms. Here is somthing I was curious about tho:

"Detonation
An interesting feature of separate rpm and torque control in constant-speed props is that at low rpms and a high throttle setting, the charge cannot be absorbed at the slower engine speed. In addition, the engine timing is thrown off, and the combustion in the engine builds tremendous pressures that severly damage or destroy the engine. For this reason, in high-powered props pilots are instructed to reduce power by first reducing the throttle and then reducing rpm, and to increase power by first increasing rpm and then advancing the throttle. In this way a high-pressure, low-rpm condition is avoided. In addition, it is a very good idea to make smooth power changes, since engines generally cannot handle jumps in manifold pressure, which can also lead to detonation.

However, much to our collective regret, such engine damage appears to not have been modeled in Forgotten Battles."

Does this mean that in Il2:FB I don't need to decrease power by first decreasing throttle then rpm and increase power by first increasing rpm and then throttle? I can change Prop. Pitch independently of the throttle with no worries?

Ace_Eloff
03-15-2005, 05:16 PM
bump.

Anyone?

ZG77_Lignite
03-15-2005, 07:11 PM
Correct Eloff, no 'detonation' effects are modeled in FB/PF. Hopefully for the new sim, Battle of Britain. However, there is no reason you shouldn't still attempt to fly correctly http://forums.ubi.com/groupee_common/emoticons/icon_smile.gif (by maintaining proper manifold pressure/RPM states).

Also remember there are about 5 (4 to 7, depending upon how you look at it) different prop systems in FB, with the Constant Speed Prop being the most common (and most effective); so different aircraft can behave quite (radically even) different.

civildog
03-15-2005, 07:32 PM
Correct, but if you don't take care with mixture and supercharger settings you can easily damage your engine. The game just doesn't send you any messages about it other than the audio and performance cues. And smoking if you don't lean it at altitude.

Ace_Eloff
03-15-2005, 09:59 PM
Ah, thanks all. The only reason I wondered about adjusting Prop. Pitch independent of throttle was because on a CPS prop plane if I have to reduce throttle first to lower my rpm, I usually don't even need to bother with the prop. pitch. So I figured maybe I could play with prop pitch to control engine rpms rather than play with the throttle, and then in those super steep dives, reduce both.

Is there any advantage in Il2:FB to reducing prop. pitch instead of throttle as a means of controlling rpm? Or does it not really matter so long as you keep your rpms under the safe limit?

Ace_Eloff
03-16-2005, 12:31 PM
bump.

JoachimvMayern
03-16-2005, 01:33 PM
I can tell you this much. With regards to prop pitch, it's more sensitive on the bf109 than it is on the fw190. I find that when flying the fw, I leave the prop pitch on auto. It doesn't seem to make a whole lot of difference. The 109, on the other hand, I manually adjust. Cruising, I like like to keep the prop pitch so that the rpms are usually at or around the low 2000 range. In a dog fight, 2500-2700 is usually the norm, but occaisionally I go as high as 3000, but not for long. Anything higher than that and your asking for engine problems.
When cruising in the bf or fw, I prefer to keep the rads fully open, if it is a short distance or medium distance mission and I have plenty of fuel to keep the engine as cool as possible before any possible air to air engagements. During combat in the 109, the rad gets moved to auto. On the way back, if I'm low or way low on fuel, the rads are fully closed and my prop pitch is a little lower to prevent overheating.