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Viper_61
03-04-2004, 05:20 PM
Just checking what sort prop settin is normal?! Using the Bf109 E/7b in the barbarossa campaign and was going fine but then engine seized again. Me with the prop all wrong again! http://ubbxforums.ubi.com/infopop/emoticons/icon_rolleyes.gif

The manual says this variant is best at 2100rpm cruise (i think) so do you select the desired throttle and then set the prop pitch till the rpm = 2100 (or whatever is desired)? Is this the general practise or is there another 'method'?

Is there any warning as to when engine seizes (I say seizes but I really mean starting to run rough) as I am checking the temp gauges and they seem fine and now I make sure that manifold pressure is around about the 1.2 mark on the gauge? Seems to just do it without warning!

Also, I noticed the prop pitch dial with the two needles. Just wondering what these actually represent as there are no real markings around the dial.

Cheers for the help but really wanna understand this 'complex' http://ubbxforums.ubi.com/images/smiley/35.gif procedure in its entirety!

Cheers all, the help is much appreciated!
http://ubbxforums.ubi.com/images/smiley/11.gif
Rob

Viper_61
03-04-2004, 05:20 PM
Just checking what sort prop settin is normal?! Using the Bf109 E/7b in the barbarossa campaign and was going fine but then engine seized again. Me with the prop all wrong again! http://ubbxforums.ubi.com/infopop/emoticons/icon_rolleyes.gif

The manual says this variant is best at 2100rpm cruise (i think) so do you select the desired throttle and then set the prop pitch till the rpm = 2100 (or whatever is desired)? Is this the general practise or is there another 'method'?

Is there any warning as to when engine seizes (I say seizes but I really mean starting to run rough) as I am checking the temp gauges and they seem fine and now I make sure that manifold pressure is around about the 1.2 mark on the gauge? Seems to just do it without warning!

Also, I noticed the prop pitch dial with the two needles. Just wondering what these actually represent as there are no real markings around the dial.

Cheers for the help but really wanna understand this 'complex' http://ubbxforums.ubi.com/images/smiley/35.gif procedure in its entirety!

Cheers all, the help is much appreciated!
http://ubbxforums.ubi.com/images/smiley/11.gif
Rob

mike_espo
03-04-2004, 05:38 PM
the Emil is more trikey to use manual prop pitch than the other variants. Keep the RPMs below 2500 and you should be OK. I usually keep it on auto unless I need to get away or climb. A chandelle is easy with manual prop pitch.

ColdWarrior1
03-04-2004, 05:55 PM
The most important thing to watch is your rpm gauge. The prop pitch and throttle need to be adjusted constantly to keep rpm's in optimal range. For example, if you dive, your prop spins faster causing your rpm's to increase. If you dont decrease prop pitch you'll fry your engine.

ZG77_Lignite
03-04-2004, 07:51 PM
I believe you have it basically right for setting prop pitch and throttle (in 'manual' mode). You must make SURE the RPM's are not going over the max rated RPM though (2100 should be a safe cruise, even on 109E models I believe). It doesn't take long to ruin an engine when running over the 'redline'.

Also, in case you mis-typed the model, the Bf109E7/Z has GM-1 (nitrous oxide I believe) system, on the War Emergency Power button. This CANNOT be engaged below 6000m, ever.

The prop pitch dial is a general indicator, and not particularly usefull for anything as your engine RPM/proppitch relationship varies with speed. I believe 12:00 (as if the guage was a clock, which is how it is read) is 'full fine', also known as '100%' for the Bf109 series. 'Full coarse' (0%) is about 5:30, forgive me as I don't remember that exactly. The clock dial varies directly related from full fine to full coarse (meaning the prop blade pitch angles) between these two numbers.

There are two temperature guages, with one of them being the more important (forgive me as I don't know whether it is coolant, cylinder head, or oil temp, assume it is coolant). Overheat on these engines is usually at about 120deg I believe (guage will be pegged unless I'm mistaken, its pegged on FW190's which I am more familiar with). Too long at this point and the engine will be damaged. Other than that there should be no reason for your engine to be damaged, barring battle damage of course.

P.S. There is a historical relationship as to setting throttle (manifold pressure) and engine RPM. I hope I get this right (I'm sure I'll be corrected if not): When Increasing power, first increase engine RPM, then manifold pressure. When Decreasing power, first lower manifold pressure, then engine RPM. I believe this is to avoid over boosting the engine (too high manifold pressure). This is not modeled in FB.

Viper_61
03-05-2004, 02:46 PM
Cheers guys, this helps. Will stop bothering you about prop questions now http://ubbxforums.ubi.com/infopop/emoticons/icon_wink.gif

Thanks.