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freakvollder
03-12-2009, 01:15 PM
When I drive the bf109 (all models) I ask me what are the best radiator settings on this plane. Can you tell me how do you use radiator settings on the 109?
I need a general rule to set the radiator and the throttle on the 109s to archive the best speed and the best economy.
My general information about power settings comes from the eastern skies website and I must say that these information sounds good for me.

How do you set the radiator at various flight conditions?
fore example:

- for cruise speed at around 60-80% throttle?
- for “normal” climbing settings at around 75-90% throttle?
- for combat climb settings above 100% throttle (+WEP)?
- For maximum speed at level flight (maximum long term performance)?

How can I get the best out of it? http://forums.ubi.com/groupee_common/emoticons/icon_biggrin.gif

I think that the “radiator closed” setting is always a good choice (low drag)< = 100% throttle.

When should I use the AUTO-setting on this plane and how does it work? Is it ever useful?

Can you tell me something about the induced drag from the radiator in relation to high power settings (>100% throttle + WEP)? In other words “is it useful to drive the engine hard and open the radiator to cool the engine, ore can I get the same ore better results with lower power settings (< = 100% throttle) and “radiator closed” fore example?
What is more effective to get the maximum speed for a long time?


I am from Germany and my English is not very good, but I hope you understand what I mean! http://forums.ubi.com/images/smilies/blush.gif

Thanks and nice greetings
Freak…

freakvollder
03-12-2009, 01:15 PM
When I drive the bf109 (all models) I ask me what are the best radiator settings on this plane. Can you tell me how do you use radiator settings on the 109?
I need a general rule to set the radiator and the throttle on the 109s to archive the best speed and the best economy.
My general information about power settings comes from the eastern skies website and I must say that these information sounds good for me.

How do you set the radiator at various flight conditions?
fore example:

- for cruise speed at around 60-80% throttle?
- for “normal” climbing settings at around 75-90% throttle?
- for combat climb settings above 100% throttle (+WEP)?
- For maximum speed at level flight (maximum long term performance)?

How can I get the best out of it? http://forums.ubi.com/groupee_common/emoticons/icon_biggrin.gif

I think that the “radiator closed” setting is always a good choice (low drag)&lt; = 100% throttle.

When should I use the AUTO-setting on this plane and how does it work? Is it ever useful?

Can you tell me something about the induced drag from the radiator in relation to high power settings (&gt;100% throttle + WEP)? In other words “is it useful to drive the engine hard and open the radiator to cool the engine, ore can I get the same ore better results with lower power settings (&lt; = 100% throttle) and “radiator closed” fore example?
What is more effective to get the maximum speed for a long time?


I am from Germany and my English is not very good, but I hope you understand what I mean! http://forums.ubi.com/images/smilies/blush.gif

Thanks and nice greetings
Freak…

Treetop64
03-12-2009, 01:52 PM
The real 109 had an electro-mechanical system that automatically regulated the supercharger, propeller pitch, fuel mixture, and radiators. It is extremely useful. Use it. Let the plane do the work. All you should worry about is the throttle, the guns, and the enemy.

Optimal cruise settings is about 2100-2300 rpm, depending on the model. The old Emils usually cruised at about 1800-2000 rpm. MCT (max continuous power) is the point where the manifold pressure indicator stops moving as you advance the throttle. When pushing the throttle forward and that needle stops moving, stop pushing the throttle. You can get good power there all day without ruining the engine. You can advance the throttle a bit further to the stops, but I would only reserve that for extreme emergency, immediate life-or-death situations, and only if you have a bit of spare room on the temp indicator. The temps will rise dramatically once you do this, and you will want to trottle back down to MCT soon or you risk damaging the engine.

Regarding the 109 series, discussing the fine details of the effects of the radiators being fully open at full power, and at high temps, becomes purely academic once you're engaged in a combat situation. You shouldn't have to worry about it, and that's how the systems on the 109 were designed. Most other planes, particularly Russian ones, required manual intervention with most, or all, engine settings, and could be quite a handful to manage as you fight your way across different altitudes and speeds! The MiG-3 was an exception for Russian fighters as the engine had automatic supercharger and mixture settings; the pilot only had to adjust the throttle and propeller settings.

Combine this engine management with sound flying tactics, and you should do well. It will take a lot of practice to get this right.

DKoor
03-12-2009, 02:02 PM
<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by Treetop64:
It will take a lot of practice to get this right. </div></BLOCKQUOTE>This is where it begins and ends.

BTW this radiator thing is like binary system: 0 (closed) = good for your flight performance, 1 (any kind of open really) = bad for your performance.

And this is where a game kicks in... just how more bad is the position 4 compared to position 2 I don't know. I guess you could always run your aircraft at full speed at deck or something and find out by comparison.

Freiwillige
03-13-2009, 04:35 AM
I did those tests not to long ago. I found that if you fly the 109 like they did in real life the performance is pretty good.

The ATA/Boost gauge has markers built into it from the G2 model on up. Those were boost limits by time. The first part of the guage markings is for cruise the second part up to the white arrow is for combat. Both of those can be flown all day long with the radiator setting closed as was done by the real pilots.
Anytime you exceeded that heat built up quickly and engine damage\extreme wear was rapid but in an emergancy it was authorised.

Now for the facts: At sea level my first test was full 100 percent throttle with flaps fully open. Result:::Was only 11 Kmh faster than with throttle set to white marker on boost gauge (85%)with flaps closed!

So for me I fly flaps closed and never exceed the 1.4 ata limit unless combat emergancy dictates and then it is quite brief.

The use of MW-50 or the fuel injected supercharger boost sytems both cool the engine and help offset overheating so in such case I will let it exceed 1.4 limit and be faster than a 109 going 110% and MW-50 with rads open!

Freiwillige
03-13-2009, 04:47 AM
Here is the post with the exact test results.


http://forums.ubi.com/eve/foru...471074517#2471074517 (http://forums.ubi.com/eve/forums/a/tpc/f/23110283/m/2471074517?r=2471074517#2471074517)

Skarphol
03-13-2009, 05:07 PM
When I look at pictures of planes that has a radiator stuck out in the airstream, and some sort of flap regulating the amount of air passing through the radiator gills, it seems logic to me that it will produce less drag if you open the flap, than if it is closed. Especially for a type of radiator like the one on the Bf-109. But this seems not to be the case. And I really don't understand why.

Skarphol

Freiwillige
03-13-2009, 06:05 PM
Well its simple aerodynamics. Radiator flaps on the 109 open so wide that they almost become air brakes! Plus the radiator itself offers considerable resistance to the flow of air and it has to slow the air down drastically to squeeze through creating drag.

Now with the radiator closed (although on the 109 its always open just a crack even in the closed poition) The air that cannot pass through the radiator stals in front of the radiator creating a buffer for the other air to go around. Since that buffer is compressable by the force of the oncoming air it can be shaped by the force into an aerodynamic ramp if you will shooting the excess air over the radiator and back into the airstream.

Aaron_GT
03-13-2009, 06:51 PM
If the flap is closed the air doesn't transit through and pools up. The air flowing over the radiator tends to flow past this 'pooled up' air.

If the flap is open the air goes through all the radiator structure which has a lot of drag due to pressure changes, etc (which good design seeks to minimise whilst still achieving the required cooling).

freakvollder
03-21-2009, 10:28 AM
hallo all

first I will thank you fore your answers http://forums.ubi.com/groupee_common/emoticons/icon_smile.gif

I have had some time for testing the Bf109: with radiator closed the 109 ist 10-15 km/h faster in level flight as with radiator on outo ore open.

you are right Freiwillige http://forums.ubi.com/images/smilies/16x16_smiley-wink.gif

Treetop64: I agree also with your post! during air combat it is verry hard to manipulate the radiator settings. I schould need my full intention fore watching the enemy closly.

can someone tell me how the AUTO-Setting ist working in the 109? It seems to be very accidental.

How can I get the best out of the engine during combat manövers like boom and zoom?

nice greetings

freak...

VW-IceFire
03-21-2009, 01:12 PM
<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by Skarphol:
When I look at pictures of planes that has a radiator stuck out in the airstream, and some sort of flap regulating the amount of air passing through the radiator gills, it seems logic to me that it will produce less drag if you open the flap, than if it is closed. Especially for a type of radiator like the one on the Bf-109. But this seems not to be the case. And I really don't understand why.

Skarphol </div></BLOCKQUOTE>
I assume you're thinking of the style of radiator the Spitfire/Hurricane/Yak/LaGG uses right? Creates more drag by opening up the radiator because air is now flowing through that section and becoming rather turbulent. Which means its going to cause drag. If its closed then the air will flow around with less turbulence than when its being forced into the radiator section (with all of the bits and pieces used for cooling in there). There is drag both ways but moreso if its open.

I'm sure there is a much more complicated aerodynamics answer so it but thats what I have locked away in my head http://forums.ubi.com/groupee_common/emoticons/icon_smile.gif

K_Freddie
03-22-2009, 01:42 PM
The Mustang designers found that it's radiator design actually increased thrust - venturi effect, when the input area &gt; output area.
The same can be done with most radiators, but I don't think this is modelled.

This extra thrust is in addition to the cleaner airflow lines resulting from closing the radiator flaps
http://forums.ubi.com/groupee_common/emoticons/icon_cool.gif

WTE_Galway
03-22-2009, 06:38 PM
<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by K_Freddie:
The Mustang designers found that it's radiator design actually increased thrust - venturi effect, when the input area &gt; output area.
The same can be done with most radiators, but I don't think this is modelled.

This extra thrust is in addition to the cleaner airflow lines resulting from closing the radiator flaps
http://forums.ubi.com/groupee_common/emoticons/icon_cool.gif </div></BLOCKQUOTE>


My understanding is the positive thrust built into the design canceled most of the drag but the P51 was still better with the radiator shut.

For an example of a plane that flies really really bad at low speeds with radiator open take the Lagg for a spin.

UgoRipley
03-23-2009, 03:25 AM
<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by freakvollder:
...during air combat it is verry hard to manipulate the radiator settings. I schould need my full intention fore watching the enemy closly... </div></BLOCKQUOTE>
It also depends on how your settings are configured, what kind/brand of joystick software you run, and if you have some "spare" buttons available.
I have one button that normally outputs one "R" key to open the radiator in small steps, and the same button (in its shifted-state) that repeatedly outputs the "R" key a few times in order to go from "full-closed" to "full-open" with only one click.
When you are in combat, twisting and turning, you bleed LOTS of energy in so many ways that for me is pretty useless to be concerned by the radiator induced drag.

freakvollder
03-23-2009, 11:33 AM
Yes UgoRipley I can understand what you mean. I personaly use no Joystick-Software - I hate the SST Software from Saitek http://forums.ubi.com/images/smilies/16x16_smiley-tongue.gif
Puch the button fore radiator on my X52 fore 5 ore 6 times to open the radiator need some conzentration but it works very good.

Lots of energy is bleeding in many ways right - in the future I will use the Auto Setting and can take my full atention on maneuvering in the 109.

Thanks