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Fangio11
03-10-2004, 09:12 PM
Is this a bug?

When I fly the 109, most recently the Emil, it will not run at higher power / rpm settings at all without instantly overheating.

I took off on a mission offline in a campaign game. After takeoff, i throttle back to power at 90%. Prop pitch is set to auto. RPMs are only pulling about 2200. The other planes in my flight start to vanish into the distance, I cannot keep up. I increase power to 100%, but only get a slight speed increase. RPMs only go to 2500. Temp guages both say normal, middle of the dial. Im wondering WTF ? So I switch to manual prop pitch, and run it up to 90% and power at 90%.... the engine noise races and within 3 seconds I get an engine overheat message. If I dont throttle back the rpms to 50% or less, the engine will self destruct within seconds. Both temp guages still read normal.

I cannot get the emil to run at any rpm over 2500 without getting an instant overheat, even with the radiator on full open?

Is this a bug? Am I missing something here?


Fang

Fangio11
03-10-2004, 09:12 PM
Is this a bug?

When I fly the 109, most recently the Emil, it will not run at higher power / rpm settings at all without instantly overheating.

I took off on a mission offline in a campaign game. After takeoff, i throttle back to power at 90%. Prop pitch is set to auto. RPMs are only pulling about 2200. The other planes in my flight start to vanish into the distance, I cannot keep up. I increase power to 100%, but only get a slight speed increase. RPMs only go to 2500. Temp guages both say normal, middle of the dial. Im wondering WTF ? So I switch to manual prop pitch, and run it up to 90% and power at 90%.... the engine noise races and within 3 seconds I get an engine overheat message. If I dont throttle back the rpms to 50% or less, the engine will self destruct within seconds. Both temp guages still read normal.

I cannot get the emil to run at any rpm over 2500 without getting an instant overheat, even with the radiator on full open?

Is this a bug? Am I missing something here?


Fang

ucanfly
03-10-2004, 09:43 PM
The combat RPMs on the Emil are supposed to be low - 2200 RPM I think, and emergency power I believe was limited to 2700 RPM or less. THis is what I remember from original README.

Jetbuff
03-10-2004, 10:11 PM
Also, keep in mind that the 109's CEM is a direct prop-pitch control, not a governor like the Antons or the VVS aircraft. i.e. you're not setting the desired RPM, you're setting the blade angle directly.

Once more: the 109 is a variable prop aircraft while the 190A's and VVS aircraft have constant speed props.

Therefore, when you go to 90% you're basically setting a VERY flat pitch angle on the blade. At full throttle and/or speed this means that you have next to nothing to load the engine and it will just run wild and that's what you're experiencing. Try setting pitch lower and adjusting continually by monitoring RPM. It's hard work.

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Von_Hoffmann
03-11-2004, 12:13 AM
do you have AEP?
this was a feature in V1.0. In V122 it should have been gone, perhaps they repatched it to V1.0 with the AEP.

DeerHunterUK
03-11-2004, 05:41 AM
Hmm if you're flying the 109 E7 you can't fly with the WEP engaged below 6,500 meters without instantly frying your engine.

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Fangio11
03-11-2004, 02:06 PM
I do have AEP.

My 109 engine is instantly fried anytime I run the pitch over an indicated 60% which shows the rpms as exceeding about 2600. How can that be right?

Even if it is direct pitch control... why would the maximum allowed setting be only 60% of the provided movement?

Also... when I am running at 2600rpm and full throttle settings... all the AI flight members are walking off into the distance. I cannot keep up with my formation. How are they managing to climb and run so much faster than me?

Ill check the readme. As it is, I cannot fly the 109 at all. http://ubbxforums.ubi.com/infopop/emoticons/icon_frown.gif


Fang

ucanfly
03-11-2004, 02:16 PM
First of all if your using CEM you should look at the tachometer and not worry too much about what the prop pitch percentage is.

Secondly it is unfortunately a well known fact that the AI does not have to worry about overheats and that if the mission you are flying requires max power to achieve the waypoints then the AI will do it and never overheat, whereas you will. Either tweak the mission to have more realistic waypoints, let the AI take over for awhile, or catch up later by not climbing as steeply at first.

Jetbuff
03-11-2004, 02:56 PM
An engine will over-rev and overheat if it is not properly loaded. Increasing pitch % (flattening the prop blades) decreases the bites it takes out of the air and hence the workload of the engine. Furthermore, the faster you're going the lower the engine load. Other factors include air density, temperature, humidity, etc.

Taking these two variables (speed and prop-angle) into account means that 100% pitch (practically flat blade) will only be of use when flying slowly (>200kph) at a high AoA. In almost all other situations this is too flat a setting for the engine to handle. OTOH, try 100% pitch on the ground and you will find you can get more out of your engine for less throttle. e.g. take-off rolls are much shorter at 85% pitch.

The simplest way I can put it is you should constantly manipulate throttle and pitch to achieve the desired rpms (2500 for combat climb and take-off, 2300 for combat cruise, 1900 for econo-cruise and 2700 for sporadic bursts of WEP). This only applies to planes that are equipped with direct control of pitch and not governors (the 109s, 110 and Doras).

For the other planes, which have governors, you are setting the desired rpms directly through the prop pitch % (i.e. it is actually a misnomer) and actual prop-pitch will vary automatically to maintain the appropriate rpms given the throttle, speed and air density. That is why the behaviour of the 109, (all variants) is so different from the rest of the planes. The only time the effect will be replicated in other planes is if you suffer governor damage.

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Vortex_uk
03-11-2004, 03:00 PM
Most BF-109s will overheat if u set the boost after u have started the engine,the E series r very ***ile,u need to keep a low prop pitch and thottle,with later versions with the MW50 boost,set the boost before u start up the engine.

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Jetbuff
03-11-2004, 03:00 PM
<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>Originally posted by Fangio11:
My 109 engine is instantly fried anytime I run the pitch over an indicated 60% which shows the rpms as exceeding about 2600. How can that be right?<HR></BLOCKQUOTE>
It's right because the 109E's engine just can't handle any more than 2600rpm for a prolonged period of time.

<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>Even if it is direct pitch control... why would the maximum allowed setting be only 60% of the provided movement?<HR></BLOCKQUOTE>
60% is not the maximum, it is the maximum under the settings you subjected it to. (probably level flight with open throttle) At slower speeds and/or less throttle you can go much higher on the prop-pitch.

<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>Also... when I am running at 2600rpm and full throttle settings... all the AI flight members are walking off into the distance. I cannot keep up with my formation. How are they managing to climb and run so much faster than me?<HR></BLOCKQUOTE>

That's different, the AI use a simplified flight model and don't suffer overheat. They will always outrun you if the mission builder gives them target speeds and altitudes that are too high for a human to achieve.

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Jetbuff
03-11-2004, 03:03 PM
BTW, the only time I find 100% pitch to be useful is at the latter stages of a zoom climb when my plane is slowing down below 150kph. At that speed, 100% pitch will allow you to 'hang' in the air just a little bit longer but you must remember to decrease percentage as soon as you hammerhead and start picking up speed.

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Cdn.401GATOR
03-11-2004, 03:20 PM
Jetbuff that is a very good explanation..

You must be an engineer.

Excellent work Sir..

The Flying Reptilian

GATOR

p1ngu666
03-11-2004, 03:32 PM
just use auto http://ubbxforums.ubi.com/infopop/emoticons/icon_smile.gif
fixes headaches u know http://ubbxforums.ubi.com/infopop/emoticons/icon_wink.gif

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Jetbuff
03-11-2004, 10:08 PM
Tx Gator. http://ubbxforums.ubi.com/infopop/emoticons/icon_smile.gif

Not an engineer though; if one came along I'm sure he'd put my simplistic explanation to shame. I'm just a very inquisitive guy is all and was fascinated by CEM when FB was first released so I did some reading.

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