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general_kalle
09-13-2006, 02:14 PM
hi i need some information on how to use pitch.

when to have much when to have little
which buttoms is smartest to use
other important things about pitch is also welcome

general_kalle
09-13-2006, 02:14 PM
hi i need some information on how to use pitch.

when to have much when to have little
which buttoms is smartest to use
other important things about pitch is also welcome

CAF96th_Sillyak
09-13-2006, 02:20 PM
prop pitch is like gears in a car. 1st gear would be 100% prop pitch and would increase he rpm of the engine. find out what the best rpm range is for the specific plane you are flying and keep the rpm in that range by increaseing or decreasing the pitch.

horseback
09-13-2006, 02:54 PM
What kind of controller setup do you have? If you're not using a HOTAS type system (or at least some kind of joystick plus control axis/button system), it strikes me as more trouble than it's worth.

I only use it for non-German a/c, and with my CH Pro Throttle, I assigned the Increase PP and Decrease PP buttons to the up-down points of the lower 4-way hatswitch nearest my thumb. That means 5% increments up or down, and I also found it useful to assign buttons to PP 0% and PP 100% for emergencies as well.

Hope this helps.

cheers

horseback

Jaws2002
09-13-2006, 02:57 PM
<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by CAF96th_Sillyak:
prop pitch is like gears in a car. 1st gear would be 100% prop pitch and would increase he rpm of the engine. </div></BLOCKQUOTE>

It only works this way in BF-109's. Bf-109 had a variable pitch prop. You had direct control over the actual pitch of the prop. This only when used on manual.

The rest of the planes are using constant pitch propellers. With this system you have control over RPM and not the prop pitch. You change the RPM and the system is automatically adjusting the pitch to maintain that RPM. In planes with CPS what you have as 100% prop pitch is actually 100% RPM. in other words the maximum RPM for that engine. when you lower the so called "prop pitch " you are lowering the RPM.

Manual PP is useful in few situations and it should be mandatory in some. You need to lower the prop pitch in dives to avoid overreving the engine (in variable prop pitch planes), or prop runaway (in the CSP planes). The later doesn't really happen in the game unless you dive with ridiculous speeds.

In the 109's you can go manual for climbs if you are desperate and need extra juice to survive. This comes with a serious danger to blow your engine. You have to know what rpm is ok for your engine and how much of that abuse it can take.
In other planes with the constant speed props you need to lower the PP a little at high speeds. Many planes are faster on straight runs at high speed, with lower then 100% PP. For acceleration higher is better usually.

One strange case is the FW-190. In game it has some sort of hybrid prop pitch system that I still don't understand. It needs manual to reach It's rated speed and you have to use it on manual in combat most of the time.


About controls for Prop pitch. I the game if you assign increase/lower prop pitch to buttons you get increments of 5%. If you use a slider or rotary dial (assigned in HOTAS section of the controls), you get smooth movement in increments of 1%. If you have enough sliders the later is much better way to use prop pitch.

Al aircraft are different so you have to experiment with them a little. Just have to know what kind of prop pitch system they have. Only 109's, 110's have variable prop pitch. all other planes use CSP.

NonWonderDog
09-13-2006, 03:10 PM
Jaws2002 beat me to it, but the gearshift analogy is a poor one. Car engines and aircraft engines operate in completely different modes. Thinking of the pitch as a gear shift will give you completely the wrong idea of its use.


Firstly, propeller pitch is rarely directly controlled. The only plane in the sim that even has direct control is the 109, and even then only in manual mode.

What is really controlled is RPM. You set the desired RPM with the "prop pitch" control, and the governor on the propeller hub will do its best to keep that RPM no matter how fast or slow you fly or how high or low your throttle setting. Of course, it does have limits, so you will lose RPM at very low speed or very low throttle, and you can overspeed the prop at very high speed. (I think every CSP-equipped plane in the sim will disintegrate before the prop overspeeds, though.)

What you want to do is choose the best RPM for your flight conditions. For takeoff, climb, or combat, use 100% RPM. This will in just about every case be the RPM setting that delivers the greatest horsepower. There are only two time you need to reduce RPM: cruise and if your engine dies. Reducing RPM for cruise will greatly decrease fuel consumption. It will also keep the engine cool. The most efficient engine settings are usually about 65% throttle and 70% RPM, although that does vary significantly between types. If your engine dies, you should either feather the blades, if the propeller supports it, or you should set the "prop pitch" to 0%. This will create the least drag.

The big difference between an aircraft engine and a car engine leads to the next point: always, always, always use 100% RPM for landing. Engine power and engine sound aren't nearly as correlated as they are in a car. At 10% throttle and 100% pitch, you are effectively using the (still rather loud) propeller as a giant airbrake. During landing you want to keep about 30% power on and 100% RPM. You want to be able to stabilize the plane in ground effect before going for a 3-point landing, and you want engine power to be immediately available in case you need to go-around.

NonWonderDog
09-13-2006, 03:14 PM
The 190 system is a bit odd. It has a CSP system as its "manual" mode, and the CSP has a higher maximum RPM than the automatic control. Using the "manual" mode you can boost RPM to 110% or so, giving you greater power at the expense of reliability.

I don't know if any of this is historical, particularly since it appears that the 190 doesn't meet spec unless you use maximum RPM in the CSP mode.

Reducing RPM at high speeds should not be beneficial. In fact, reducing RPM at high speeds without first reducing throttle can be extremely damaging to your engine in real life. If it makes you go faster in the sim, it's simply a bug in the flight model.

Xiolablu3
09-13-2006, 03:21 PM
Surely 100% pitch would be more like top gear on a car?

Its taking the biggest 'bite' out of the air and so is like running at full speed.

Wouldnt first gear be a very low prop pitch, so that its easier for the prop to spin, but not taking as big 'bites' of air?

I would have thought that a lower prop pitch would make it easier for the egine to turn the prop, becasue there is less air resistance.

Maybe I understand wrongly how it works. I never actually use it.

Viper2005_
09-13-2006, 04:36 PM
"Prop pitch" in game is actually really rather a misleading term.

If you've got a constant speed prop, 100% "prop pitch" has the effect of asking the engine for 100% rpm.

If you've got a manual prop, 100% "prop pitch" puts the prop into fine pitch, whilst 0% "prop pitch" puts the prop into coarse pitch.

If you fly the Fw-190A in game you really need to use prop pitch to get full performance. I use 100% for takeoff and slow flight, and 90% the rest of the time. It makes quite a big difference to your top speed; without it the engine doesn't give full rpm and you're down on power. Since I fly the Fw-190A a lot, I have a hat switch devoted to prop pitch control.

I always fly the Dora in manual.

Whatever you're flying, if you lose the engine and can't feather the prop you'll find that glide performance improves if you set prop pitch 0%. Remember to close the radiator too; it can make all the difference.

WB_Outlaw
09-13-2006, 05:44 PM
The car gearbox is a poor analogy since the prop actually slips through the air. A better analogy is to imagine a car that only has one gear and that the pitch controls the amount of traction the tire has. So with fine pitch your tires spin more than they do in coarse pitch.

With direct prop pitch control 100% (or fine) pitch takes the least "bite" out of the air allowing the engine to turn faster and thus generate more horsepower (note that the prop also turns faster but it is geared to turn slower than the engine-not sure of the ratio). Depending on the conditions, the smaller "bite" is made up for in RPM. As you increase altitude, the density of the air drops calling for more pitch to produce the same thrust.

If you stand in front of the aircraft and look at the prop set at fine pitch, you will see nearly the full width of the blade. As you coarsen the pitch, the blade will twist so you see less and less of it until it is feathered where you will be looking at the edge of the blade (or nearly the edge since the prop blade is shaped just like a wing).

With fine pitch set, as the blade is turned by the engine, it moves a smaller amount of air. Now, what happens when you pull the power off? The prop is now being turned by the air, not the engine. The flat of the blade deflects the air away, thus turning the prop. So, let's say that your max safe RPM is 3,000 at and your max speed at that RPM is 200 knots at 10,000 feet with fine pitch. If you dive and exceed 200 knots with fine pitch, your RPM will increase above 3,000 even if you have the engine off (give or take). So, with direct pitch control (or fixed pitch), it is easy to overspeed the engine and/or gearbox by going too fast. If you're in a multi-engine aircraft you can even exceed the safe RPM without diving because of additional power from the other engines. The biggest danger of not feathering an engine in a 4 engine bomber is not the extra drag, it's the induced RPM. If you lost an engine and couldn't feather it, you had to slow down (and drop out of formation) to keep from overspeeding the prop. In a crowded formation you can't just drop out whereever you want to so there were many cases where the prop actually tore itself off before the crew could slow down enough. Having the prop come off in flight is a bad thing. If you are heavily loaded and can't maintain altitude below the safe RPM speed, you are in big trouble.

A properly working constant speed prop will adjust the prop pitch automatically so that the engine never exceeds the "set" RPM. The "set" RPM is what you are changing when you change the pitch in a CSP setup. The 100% condition is the max safe RPM for the engine.

I'll shut-up now.

--Outlaw.

TeufelHund84
09-13-2006, 06:30 PM
General_K, I think there's a file somewhere in your Il2 install that details recommended engine settings for all (or at least most) of the aircraft in different situations i.e. combat, cruising, takeoff, landing, etc etc.

But this is only rumor to me as I now have 4.04m and can't find the damn file anywhere and lord knows I could use it!!!!!!!!!! http://forums.ubi.com/images/smilies/sadeyes.gif

Anyone know where such a file exists? Neural Dream's aircraft PDF is a good start but it's not all encompassing.


Speaking from my personal experience, using prop pitch does precisely...nothing. I do indeed have it on 100% for combat, takeoff, and climb, and I try to turn it down for low key activity, but I notice exactly ZERO change in anything I do beyong the noise of the engine and my RPM needle. Granted, I don't have many hours logged of a variety of a/c (just the 109 which says something) but seeing as how I'm becoming a convert to the FW190/ BnZ side, I suppose I can see where it would be useful.

I hear people complain that CEM in this game is not as sim-like as it should be. If it was, would people like me more readily notice differences when using prop pitch?

JG53Frankyboy
09-13-2006, 06:44 PM
<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by TeufelHund84:
General_K, I think there's a file somewhere in your Il2 install that details recommended engine settings for all (or at least most) of the aircraft in different situations i.e. combat, cruising, takeoff, landing, etc etc.

But this is only rumor to me as I now have 4.04m and can't find the damn file anywhere and lord knows I could use it!!!!!!!!!! http://forums.ubi.com/images/smilies/sadeyes.gif

Anyone know where such a file exists? Neural Dream's aircraft PDF is a good start but it's not all encompassing.


Speaking from my personal experience, using prop pitch does precisely...nothing. I do indeed have it on 100% for combat, takeoff, and climb, and I try to turn it down for low key activity, but I notice exactly ZERO change in anything I do beyong the noise of the engine and my RPM needle. Granted, I don't have many hours logged of a variety of a/c (just the 109 which says something) but seeing as how I'm becoming a convert to the FW190/ BnZ side, I suppose I can see where it would be useful.

I hear people complain that CEM in this game is not as sim-like as it should be. If it was, would people like me more readily notice differences when using prop pitch? </div></BLOCKQUOTE>

well, i think your crewchief would be thankfull if he and his men would not need to change the engines so often !
and in real range/endurance was much more important than in game.

do you think a real 109 could fly with 103% power, MW50 enabled, Cooler open for 26minutes (than the MW50 is emtpy).
or a P-51 could fly from england to Berlin and back with alwasy Military power setting (100%) and 100% pitch (means maximum engine revolutions)..................



in general, in some planes in game you have to care about the CEM more , in others less.

think about that a B-25J or F4U are overheating in game with cooler open, pitch 100%, power 100% !
to avoid this, reduce the settings http://forums.ubi.com/groupee_common/emoticons/icon_wink.gif


or if you flying online as a leader, you have to reduce both, power AND pitch to slow enough down that your wingmen can catch up formation - im doing mostly 70% power and 80% pitch than.
sure , in a Bf109, Fw190 or Spit IX/VIII (all in auto mode), you only have to reduce the throttle.