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FatBoyHK
05-07-2004, 07:48 AM
My TM Cougar is half-dead now, and while waiting for my U2 Mod, I freed myself from active duty and back to the flight school.... to learn CEM.

I started in USAAF planes first. I found that instead of playing with prop pitch directly I am actually given control of the RPM governor... After some trial I found that, if I need power, I can just leave it on the MAX setting, and that is.....I can't find any use of changing it... Am I wrong?

Also, seem I can't change the fuel mixture, even after I assigned the key in the control menu...I did something wrong?

FatBoyHK
05-07-2004, 07:48 AM
My TM Cougar is half-dead now, and while waiting for my U2 Mod, I freed myself from active duty and back to the flight school.... to learn CEM.

I started in USAAF planes first. I found that instead of playing with prop pitch directly I am actually given control of the RPM governor... After some trial I found that, if I need power, I can just leave it on the MAX setting, and that is.....I can't find any use of changing it... Am I wrong?

Also, seem I can't change the fuel mixture, even after I assigned the key in the control menu...I did something wrong?

BaldieJr
05-07-2004, 07:51 AM
Get in QMB all by yourself. Trim for level flight with 80% throttle and 100% pitch.

Once everything settles, retrim as needed and record your speed.

Do it again at 75% pitch and record your speed after trimming etc.

Now open the manual on CD2 and look up the plane you were in. It'll tell you what RPM you should be at for MAX POWER, which does not always equate to 100% pitch.

I REPEAT: MAX POWER DOES NOT ALWAYS EQUAL 100% RPM. OVER.

<pre class="ip-ubbcode-code-pre">
Specs:
More expensive than the dining set.
Less expensive than the couch.
Smaller than the dishwasher.
Just as noisy as the refridgerator.
Faster than the cars' computer.
Less practical than the car.
Face it, people who put thier computer specs in thier signature are pretty ****ing wierd.

</pre>

FatBoyHK
05-07-2004, 08:14 AM
<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>Originally posted by BaldieJr:
I REPEAT: MAX POWER DOES NOT ALWAYS EQUAL 100% RPM. OVER.

<HR></BLOCKQUOTE>

Max RPM does mean max power, it is what I read from the manual... may be I get it wrong? or you actually mean prop pitch?

BaldieJr
05-07-2004, 08:29 AM
Its not safe to say "max power = max rpm" because in a dive, max rpm can kill your engine.

In the P-51 you can over-rev in level flight if you aren't carefull, and the german birds, well, they'll over-rev if you look at them funny http://ubbxforums.ubi.com/infopop/emoticons/icon_smile.gif

I wish there was more of a penalty for WEP abusers and constant over-heaters. Engines of the time were running on the ragged edge of thier performance envelope, but thats not the case in FB. We can run an engine hard for very long periods before it finally gives up.

<pre class="ip-ubbcode-code-pre">
Specs:
More expensive than the dining set.
Less expensive than the couch.
Smaller than the dishwasher.
Just as noisy as the refridgerator.
Faster than the cars' computer.
Less practical than the car.
Face it, people who put thier computer specs in thier signature are pretty ****ing wierd.

</pre>

FatBoyHK
05-07-2004, 08:42 AM
<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>Originally posted by BaldieJr:
Its not safe to say "max power = max rpm" because in a dive, max rpm can kill your engine.
<HR></BLOCKQUOTE>

Yes it is true. But I found that the RPM governor actually is doing a good job of keeping the RPM constant even in a dive. It won't last forever (as there is a physical limit for prop pitch adjustment), and I need to cut throttle in a prolonged dive eventially, but the RPM governor give me a big margain for error http://ubbxforums.ubi.com/infopop/emoticons/icon_smile.gif

<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>Originally posted by BaldieJr:
In the P-51 you can over-rev in level flight if you aren't carefull<HR></BLOCKQUOTE>

I can't overrev a Mustang.....As I just said, I think the RPM governor is working well.... It keeps the RPM for me at whatever RPM I set, even I engage WEP.... May be I still have some system running in Auto, so I can't do that?

BaldieJr
05-07-2004, 08:50 AM
Pardon my mistake, I think I recall not over-reving the 51 since AEP. I don't fly that thing much, but I recall it being easily over-reved in one of the earlier versions.

The P40 will over-rev though. Its one of the reasons why its a good plane: if you ride the pitch in a steep dive, she'll haul butt.

I think the mixture is stuck in auto on the 51. I never get a lot of altitude so I rarely have to tinker with it.

<pre class="ip-ubbcode-code-pre">
Specs:
More expensive than the dining set.
Less expensive than the couch.
Smaller than the dishwasher.
Just as noisy as the refridgerator.
Faster than the cars' computer.
Less practical than the car.
Face it, people who put thier computer specs in thier signature are pretty ****ing wierd.

</pre>

ZG77_Lignite
05-07-2004, 09:28 AM
You've got it right FatBoyHK, well done, CEM is a complex subject and is difficult to grasp (and thus is hotly debated). For other experiences, Polish P.11c for a 'fixed' prop (not constant speed like the American aircraft) or the FW190 series for a 'full auto' (Kommandergerat) system, or the Bf-109 series in 'manual mode' with its directly pilot adjustable pitch.

Though far from perfect (what simulation could ever be perfect?), FB simulates prop pitch better than any other sim to date, in my humble opinion at least.

FatBoyHK
05-07-2004, 12:03 PM
Can I make a (bold) statement here?

The major objective of CEM is to achieve the desired RPM by variating Prop Pitch.

If I am wrong, pls *** in my face directly to set me straight http://ubbxforums.ubi.com/infopop/emoticons/icon_smile.gif

El Turo
05-07-2004, 12:14 PM
The objective is to provide added fidelity to the simulation experience.

Really, it's not that complicated.

You have control over mixture (used rarely), supercharger (used rarely), radiator (used sparingly) and prop-pitch/RPM which is used quite a bit.

So, really.. the only thing that's changing is that you have more radiator options over the non-CEM version and you have control over your prop-pitch/RPM which MAY result in some increases in performance in certain situations.


Here's the simple version:

Allied aircraft: What is called "pitch" is actually just setting your desired RPM and letting governors take care of the rest.

Axis aircraft: Auto-pitch unless you select "manual" control. Fw190 is like Allied Aircraft while Me109 is actually controlling your pitch. Ironically, this is the ONLY situation in which you are actually modifying your "prop pitch".

With the actual prop-pitch situation you will have to use the pitch to keep your RPM within acceptable limits. This also means that you can push beyond your "red-line" for very very short periods of time (seconds) and get a small amount of extra performance... it's like the difference between driving an automatic and a manual shift in a car. Generally, the stick-shift is going to produce better acceleration and fuel economy while the automatic will keep you from over-revving the engine.

BTW.. you spent the money on a Cougar but never used CEM before?

http://ubbxforums.ubi.com/images/smiley/blink.gif

CEM is WELL worth the small effort required in added fun, realism and fidelity.

Callsign "Turo" in IL2:FB & WWIIOL
______________________
Amidst morning clouds
Fork-tailed devil hunts its prey
Lightning strikes, süsse träume.

BaldieJr
05-07-2004, 12:23 PM
You are correct.

But what you fail to realize is this has been covered in over 500 other posts, and that every time someone makes a general statement about prop pitch, 15 people realize that they still dont get it and start the whole ball of confusion rolling again.

I was not yelling at you, I was merely attempting to keep 5 CEM posts from happening today. I do appologize for that as I really and truely meant no harm to you.

3000 RPM is where the mustang makes max power. If you go over that you waste the engine and don't put best torque to the prop. Thats all anyone needs to know about CEM in this game (except for the fact that each plane makes max power at a different RPM, and this information can be obtained in the manual on CD2).

<pre class="ip-ubbcode-code-pre">
Specs:
More expensive than the dining set.
Less expensive than the couch.
Smaller than the dishwasher.
Just as noisy as the refridgerator.
Faster than the cars' computer.
Less practical than the car.
Face it, people who put thier computer specs in thier signature are pretty ****ing wierd.

</pre>

FatBoyHK
05-07-2004, 12:28 PM
H_Butcher, I am new to FB, joined recently after the release of AEP.... it is a shame, right? http://ubbxforums.ubi.com/infopop/emoticons/icon_redface.gif

Reason? Just like other, I have less interest with eastern front... but now, tried Yak, La, even IL2, and I simply love them as much as my favoite Mustang....Indeed, I regret what I had missed in the last 2 years... The god of simulation! pls forgive me! http://ubbxforums.ubi.com/images/smiley/35.gif

LeadSpitter_
05-07-2004, 01:56 PM
If anyone watched the chn tournment track you can see they were overheating the majority of the time. then a simple 0 pitch and 0 trottle for a few seconds and back to normal

http://img14.photobucket.com/albums/v43/leadspitter/newsig.jpg

FatBoyHK
05-07-2004, 02:22 PM
<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>Originally posted by LeadSpitter_:
If anyone watched the chn tournment track you can see they were overheating the majority of the time. then a simple 0 pitch and 0 trottle for a few seconds and back to normal
<HR></BLOCKQUOTE>

Oh? I just know they used manual prop pitch to overrev for a short period but repeatedly to enable them to climb much faster... IMO it is an exploit.... but I am no expert in CEM hence I have no say in this issue http://ubbxforums.ubi.com/infopop/emoticons/icon_biggrin.gif

LeadSpitter_
05-07-2004, 02:42 PM
yeah they over rev then switch to manual in the climb, you can see with the online islands map the one with the huge tarmac, the 109s and bf110 are out running every single plane off the ground, next are the 120 mix aircraft then the us econo mods are left far behind even the p38 which had a very quick take off and excellent accelaration. The 190a's seem like they are in econo mod with super slow accelaration off the ground as well even with manual pitch, talke a look at the dora vs the me262 takeoff run

http://img14.photobucket.com/albums/v43/leadspitter/newsig.jpg

El Turo
05-07-2004, 02:52 PM
<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>Originally posted by FatBoyHK:
H_Butcher, I am new to FB, joined recently after the release of AEP.... it is a shame, right? http://ubbxforums.ubi.com/infopop/emoticons/icon_redface.gif

Reason? Just like other, I have less interest with eastern front... but now, tried Yak, La, even IL2, and I simply love them as much as my favoite Mustang....Indeed, I regret what I had missed in the last 2 years... The god of simulation! pls forgive me! http://ubbxforums.ubi.com/images/smiley/35.gif<HR></BLOCKQUOTE>

Wasn't trying to rag on you.. it was just a bit of an odd combination to see a top of the line HOTAS and no-CEM is all. http://ubbxforums.ubi.com/images/smiley/16x16_smiley-very-happy.gif

I made the assumption that you've been in IL2 all along and not using CEM.. my mistake!

I've just recently (last 4-5 months) made IL2 my full-time flight simulator. No flight simulator is without flaws, including this one, but I enjoy my time here more than anywhere else right now.

!S

Callsign "Turo" in IL2:FB & WWIIOL
______________________
Amidst morning clouds
Fork-tailed devil hunts its prey
Lightning strikes, süsse träume.

Locust_
05-07-2004, 02:54 PM
The other day i was flying with a friend

I was @ 100 Throttle & 100 Pitch we were bolth @ 6000m in p51 the early model....

He started pulling away preaty good & I asked him his PP setting he sayes 100PP I said what the heck is your throttle @ he sayes 70% throttle....

This makes me think that possibly lower throttle in p51 & high alt might be a good thing
need to test this theory more extensivaly!

http://img20.photobucket.com/albums/v61/AFJ_Locust/161ssig.jpg

FatBoyHK
05-07-2004, 03:01 PM
Locust_ i think it is quite impossible.... if you both were on 109s I may believe your story, because you can set the PP directly on a 109 and you may achieve better result with different TH/PP combination.... but on a Mustang, you can control TH and RPM only, the fact is that higher TH and higher RPM always equal to higher power.....

El Turo
05-07-2004, 03:07 PM
Could have been radiator settings as well... that can make a significant difference in top speeds.

Callsign "Turo" in IL2:FB & WWIIOL
______________________
Amidst morning clouds
Fork-tailed devil hunts its prey
Lightning strikes, süsse träume.

FatBoyHK
05-07-2004, 04:42 PM
yes I found that having your rad closed is way better than pushing the throttle all the way to 110%....

Locust_
05-07-2004, 09:02 PM
a rgr I alwayes have my rad open so maybe he had his closed.....

http://img20.photobucket.com/albums/v61/AFJ_Locust/161ssig.jpg

El Turo
05-07-2004, 09:07 PM
The higher your speed gets, the more of an impact drag has on your flight envelope. I'm not 100% sure, but I believe it is an exponential curve..

So, the faster you're going, the more benefit you're going to get from a clean airframe (like closed radiator).

Give it a try in the QMB. Set yourself up for level flight at 110% throttle, WEP and Rads full open, record max speed attained.

Try again (after quick acceleration at 110% throttle to near full speed) with radiator at 2 or closed, throttle at 90-100% and take note of your top speed reached and heat buildup.

You may be suprised by the results.

!S

Callsign "Turo" in IL2:FB & WWIIOL
______________________
Amidst morning clouds
Fork-tailed devil hunts its prey
Lightning strikes, süsse träume.

FatBoyHK
05-08-2004, 11:00 AM
I heard someone suggest that when I need power, I should check my speed first. If I am slow, go for WEP and full rad, if I am fast, 90% throtle w/ rad closed should be a better choice.