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discovery_il_2
07-10-2008, 06:30 PM
What is relly prop pich and what it does? http://forums.ubi.com/groupee_common/emoticons/icon_rolleyes.gif

Tully__
07-11-2008, 06:34 AM
Propeller pitch is the angle of attack of the propeller blades (how big a bite they take out of the air). The higher the angle of attack (co**** pitch) the more air they grab but also they create more drag on the engine. Also, at a given pitch setting the engine will speed up as the aircraft speeds up (for example if you dive the aircraft) and vice versa.

In many aircraft in the game, the control called "Propeller Pitch" actually controls the speed setting (in revolutions per minute - RPM) of the propeller. It governs propeller (and engine) speed by adjusting the pitch towards course when the engine is running faster than the setting and adjusting the pitch towards fine when the engine is running too slow.

julian265
07-11-2008, 07:28 PM
All the info you'll need is in the above post, however, to summarise and prevent mis-use:

Prop pitch percentage controls engine RPM. Leave it at 100% for the most power, speed, and acceleration when at full throttle.

There are exceptions:

I've heard the tempest benefits from reduced prop pitch (85%) when in diving and with boost enabled (otherwise the engine revs past it's peak power RPM)

The 190's engine will over-rev and die when diving fast in manual mode at 100%.

In the 109's manual mode, the prop pitch percentage DIRECTLY controls prop pitch... so you'll have to change it continuously when your speed changes (like gears in a manual car)

PanzerAce
07-11-2008, 08:34 PM
Originally posted by julian265:

In the 109's manual mode, the prop pitch percentage DIRECTLY controls prop pitch... so you'll have to change it continuously when your speed changes (like gears in a manual car)

which is why you should just leave it on auto all the time http://forums.ubi.com/groupee_common/emoticons/icon_smile.gif

julian265
07-11-2008, 08:58 PM
Agreed.

DaddyAck
07-11-2008, 10:26 PM
yep, just another reason to fly the 109. http://forums.ubi.com/images/smilies/winky.gif Talk about a mount that is easy on it's rider. I cut my virtual aviation teeth on the 109, and would not trade her for nothing.

Xiolablu3
07-11-2008, 11:04 PM
Didnt 109E's in the battle of Britain have manual pitch?#

German pilot comments for mid-1940, they are talking about the 109E...

Oberleutnant Ulrich Steinhilper of III/JG 52 :

We began our climb almost immediately after take-off and he was
constantly using the radio to ask us to slow down so that he could keep
up. It was obvious that he wasn't manipulating the pitch control with
the skill of the more seasoned pilots to produce the same power as our
machines. We tried to tell him what to do on the radio but to no avail.
Eventually, about half way across the Channel at 4,000 metres Kühle told
him to leave the formation and return to base.'


Leutnant Erich Bodendiek, II/JG 53 :
'I was not flying my usual plane but, as I was the Technischer Offizier,
I had to fly a plane with a new automatic propeller just to test it.
That was my bad luck, having that bloody plane on that day for the first
time because that 'automatic thing' turned that angle of the propeller
so that an average speed was always maintained and not a kmh more! That
meant trouble when starting and trouble at high altitude as the plane
was nearly always unmanoeuvrable and swaggered through the air like a
pregnant duck.
It was fine weather with clouds at an altitude of about 8,300m and out
of this swung the RAF fighters when we were at 8,000m. They were
obviously directed by radar but just missed us as they came out of
clouds about a kilometre to the right of us. The Gruppen Kommandeur, Hpt
von Maltzahn, did the best he could by climbing and trying to hide in
the clouds. Everybody succeeded but me, thanks to my excellent
propeller. My aircraft could not climb like the others had and therefore
all the RAF fighters turned on me and I had no chance of escaping by
diving as that wonderful propeller would ensure that I would travel at
just 300 to 350kmh. Therefore I decided to fly straight ahead trying to
gain altitude a metre at at time, perhaps reaching cloud without being
shot down. I saw the Spitfires flying around me and shooting and my
plane was hit several times... He then hit my my fuel tank which caught
fire immediately. Within a second, my cabin was full of smoke and fire
and I had to get out.'

Manu-6S
07-12-2008, 01:43 AM
People in England could recognize who were the Germans and who were their pilots simply listening the sound of the engines.

Germans were used to change manually the prop pitch at higher altitude for the supercharger usage. Two steps every time:

1) Change the PP to have high RPM to fill the supercharger with air in lesser time (in IL2 something like PP > 90%)
2) Change the PP to optimal degree to use the supercharger and give a boost to the airplane.

So the plane was constantly an HIGh RPM, LOW RPM... HIGH RPM, LOW RPM... and so on.

England pilots had not this "problem".

WTE_Galway
07-13-2008, 06:47 PM
Originally posted by Xiolablu3:
Didnt 109E's in the battle of Britain have manual pitch?#


Indeed that is correct. in fact Emil's in this game had only manual pitch around the time of the FB release as well.

If I recall correctly, someone presented Oleg with data that showed by the time of Barbarossa (the period our Emil's are meant to model) most Emils had converted to auto pitch and he then changed it in the game.