Prop Pitch question...

[revi]

Im with you Flyby...I cant read anymore theory on the pp (though what I have read is interesting). Can somebody now tell me how and when they use pp in IL2?

[Rama]

Originally Posted by BSS_Sniper

He also stated that input from the throttle does NOT change prop pitch.

.../...

You may be saying that introducing more throttle (power) will cause the governor change the prop pitch to take a bigger bite of air to hold the RPM's the pilot set. Am I getting close to what you mean?

The later is correct (and what I allways said).

You can see the contradiction with the first sentence?

You can also look at the text quoted by Loco-S.... especially this part:

Once a specific r.p.m. is selected, a governor automatically adjusts the propeller blade angle as necessary to maintain the selected r.p.m. For example, after setting the desired r.p.m. during cruising flight, an increase in airspeed or decrease in propeller load will cause the propeller blade angle to increase as necessary to maintain the selected r.p.m. A reduction in airspeed or increase in propeller load will cause the propeller blade angle to decrease.

Which is also what I allways said.

[Ironman69]

ok guyz, to help you all with PP settings as they relate TO THIS GAME, is this:

Automatic props ( german, british ) don't worry about them.

CSP equipped planes ( USA, USSR, Japan ): Take off: Full throttle 110%/ PP= 100%

Ballz-to-the-wall full on speed run: Full throttle/ PP=95-90%
why 95 to 90? try this: take a p38L late and go full throttle and fly as fast as you can on the deck....the plane hits a brickwall at about 470kph IAS and refuses to go any faster. Now keeping full throttle, adjust your prop pitch to 95-90% and watch your speed jump to about 570kph IAS.

Dogfight: Full throttle 110%/ PP=100% Since dogfighting takes place at slower speeds ~300kph and lower....you'll need max power and ur prop blades grabbing the most air as possible to keep you from stalling at high angles of attack.

Cruise: throttle 50-60%, PP=60% . A good rule of thumb that I go by when cruising is if I throttle back power to say...50%...I also pull my pp lever to nearly 50%. Keep ur throttle and pp levers on same % and you'll be doing good.

Dives: Throttle back and pp back to nearly 50%. The game's aircraft dive rate is incredible and they all pick up speed very fast...no need to overwork ur motor by keeping it at 100 throttle and pitch..this actually hinders ur initial dive rate. Pull ur prop pitch back during a dive and you'll dive like the devil @!!@

AND THAT'S ALL YOU NEED TO KNOW ABOUT PROP PITCH IN THIS GAME.

[Rama]

Agree with all Ironman.

I could also add (also strictly for IL2):
- if your engine is damaged, reduce PP, it will last longer
- if you're low fuel, reduce PP to 0%-5%, your engine will heat, but you will save maybe enough fuel to reach base (against, it's IL2.. real thing is different)

In fact, all planes in IL2 are equiped with CSP, except a few with fixed pitch (TB3, Gladiator, CR42, maybe a few others...)
There are also those with fully atomatized CEM, like:
- Bf109/Bf110 (if auto is off, then pitch is fully manual... don't use it without strong experience)
- FW190 (if auto is off, then pitch is CSP controlled)

[II./JG1_Krupinski]

This is always a source of confusion for many reasons. First, there is many types of prop pitch setups in IL-2, as there were in the real planes. Second, people have a misconception about the idea of changing the pitch of a prop.

After reading the first page and a half, I just have to post and hopefully clear the air.

First, adjustable pitch props are just like transmissions in a car. BUT, this is in the sense of ALLOWING the driver or pilot to set the engine RPM. In a race car, the transmission is geared to put the RPMs at or close to where the engine produces maximum power.

In a sedan, the transmission is not geared the same way, and a balance between power and efficiency is made.

When an engine is producing power, it doesn't do so linearly across the RPM and power output doesn't just keep going up with RPM. There is a curve where at low RPMs its producing a low amount of power, at higher RPM the engine will be producing more power; BUT at max RPM the engine MAY NOT be producing max power. However, power output is directly related to RPM. There is a POWER CURVE related to RPM.

Since the above paragraph is true, you want some tool to allow the pilot to set the RPM of the engine. In combat situations, he would want to set the RPMs where ever the engine produces most power, at the peak of the power curve. In cross country situations, the pilot would favor efficiency over power output so he may set the engine RPMs lower than peak so to save on fuel and engine life.

There are a handful of types of adjustable props in the game. The best is a CONSTANT SPEED PROP. This term is misleading as it really dictates the speed of the engine, not the speed of the prop. This type is found mostly on the US birds such as the P51. What happens is the pilot finds the RPM he wants to use (ie 2500) and sets the pitch to keep the engine @ 2500 rpms. The neat part now is, no matter what throttle settings he uses the governor will dynamically adjust the pitch of the prop so the engine maintains a constant speed of 2500 RPM. Now, at really power settings, the engine just can't produce enough power and the governor is set to NOT go to a 0° propeller AoA, so the RPMs will drop at low settings. The big payoff with this system, is the RPMs will be constant at all airspeeds, without intervention from the pilot.

The next type of adjustable pitch propeller is just that; The Adjustable Pitch Propeller or Variable Pitch Propeller. The german fighters are built like this, IN GENERAL! (I say in general because 190 & 109 prop systems are similar they are really different) In this system, the pilot has direct control over the pitch of the prop. But again, the pilot would want to set the pitch to dictate the engine RPM's for he given situation. BUT... BUT... BUT... He must constantly change the pitch as his airspeed changes. In a climb, he has to apply a finer setting (closer to 100%), in a dive he has to apply a coarser setting (closer to 0%). Else in the former case he'll stall out or in the latter burn his engine up due to the high RPMs. Even straight and level flight needs attention as generally the airspeed increases so therefore you must use a coarser setting to maintain the same RPMs. In this system the RPMs will change also with throttle setting. Its a relationship between throttle, pitch setting and air speed; if any of these change, so does the RPMs. Therefore the pilot must constantly manually change the pitch setting.

NOTE: 100% PITCH DOES NOT EQUAL 100% POWER AT ANY THROTTLE SETTING! More RPMs does not mean go faster. It's all about setting the engine to the RPM at which it produces the maximum power for any throttle setting*.

*Even if the throttle isn't @ 100% or above, the engine still has a power curve, it's peak is the same RPM at max power, but it's just not putting out max power.

Note: 190 is NOT a Constant Speed Propeller.
Petition to get power curves published!

[Rama]

Originally Posted by II./JG1_Krupinski

Note: 190 is NOT a Constant Speed Propeller.

It is IN GAME, when kommandogerät is OFF (once you set the automatism off).
When automatism is on, then of course the kommandogerät drives the pitch along with mixture, turbo, etc....

[II./JG1_Krupinski]

Originally Posted by Rama

It is IN GAME, when kommandogerät is OFF (once you set the automatism off).
When automatism is on, then of course the kommandogerät drives the pitch along with mixture, turbo, etc....

kommandogerät is not a CSP, CSP will maintain a constant engine rpm regardless of throttle.(within reason)

This is not true with kommandogerät. Reduce your throttle, your RPMs will also reduce.

kommandogerät is really just an automatic VPP system tying pitch and throttle to rpms.

-Raven

[Rama]

Originally Posted by II./JG1_Krupinski

kommandogerät is not a CSP, CSP will maintain a constant engine rpm regardless of throttle.(within reason)

This is not true with kommandogerät. Reduce your throttle, your RPMs will also reduce.

kommandogerät is really just an automatic VPP system tying pitch and throttle to rpms.

-Raven

You're absolutly right.... but it doesn't contradict what I said
Read what I said.... I never said Kommandogerät is CSP.

When Kommandogerät is ON, then it manage the whole stuff (including pitch)
BUT.... when Kommandogerät is OFF (one you turned it OFF), THEN (and only then) Pitch is CSP controlled.
Try it in game, first turn the kommandogerät OFF, then you will see RPM will be fixed for a given position of the PP lever.

[II./JG1_Krupinski]

Originally Posted by Rama

When Kommandogerät is OFF (one you turned it OFF), THEN (and only then) Pitch is CSP controlled.

On or off, the 190 is never a CSP. CSP maintains a constant engine rpm regardless of throttle setting (within reason). That is why it's called constant speed propeller.

Again, reduce your throttle (Kommandogerät OFF) and your RPMs reduce. That is NOT CSP that is VPP.

[Rama]

Originally Posted by II./JG1_Krupinski

On or off, the 190 is never a CSP. CSP maintains a constant engine rpm regardless of throttle setting (within reason). That is why it's called constant speed propeller.

Again, reduce your throttle (Kommandogerät OFF) and your RPMs reduce. That is NOT CSP that is VPP.

You obviously haven't tried with Kommandogerät off..... try and you'll see I'm right (reduce or increase throttle, and RPM wont move).
I'm of course talking in game, not real.