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FI__Macca44
12-19-2003, 05:20 PM
Hi

can anyone give me good and extensive explanation how to use prop pitch in FB, esp in Russian planes? I don't know how to relate it to speed,alt ,and RPM,when the pitch should be 0 % and when100%



thx in advance

FI__Macca44
12-19-2003, 05:20 PM
Hi

can anyone give me good and extensive explanation how to use prop pitch in FB, esp in Russian planes? I don't know how to relate it to speed,alt ,and RPM,when the pitch should be 0 % and when100%



thx in advance

Weather_Man
12-19-2003, 05:28 PM
I don't bother with rpm and all that, but have found 85% seems to work in most situations. A bit higher may give an extra boost when running or climbing, but I generally don't bother to adjust it. Set it to 0% when try to slow quickly for landing or in prolonged dive.

antifreeze
12-21-2003, 06:53 PM
Here is a good document about engine management, which also explains prop pitch:
CEM document (PDF file) (http://www.forgotten.battles.pulpo.co.uk/CEM.pdf)

Engines are built to work within certain limits of power and revolutions; use prop pitch to keep the engine within these limits. How much pitch depends on your speed, altitude and climb/dive rate. The working RPM of each plane is given on one of the FB CD's (Flyable Aircraft Guide PFD file).

Generally lower pitch (smaller percentage) when diving, flying at higher altitudes or trying to coax top speed during level flight. Raise the pitch (larger percentage) when climbing.

How much raising and lowering depends on the plane. OKL planes need a lot more adjustment than VVS (which can usually be toggled between 90-100%). Just listen to the engine noise (rumbling too low or whining too high?) and you'll probably do OK. It's exactly like using bicycle gears to go up and down hills.

http://forgotten.battles.pulpo.co.uk/il2logo.gif

Vgamer_248th
12-21-2003, 09:25 PM
I read that PDF file, but a few things don't work correctly in the sim. Where it says that lowering the prop pitch will allow you to go faster, i just tried that and it doesn't work. 100% prop pitch and 100% throttle is close to max rpm (in the P47 at least) and if you lower the prop pitch you will slow down. The other thing is that i've never been able to overrev any allied aircraft, ever, even in a dive. Everything in the PDF makes sense and sounds correct, so is it just me then, or is prop pitch still not 100% correct in FB?

Vgamer
XO 248th Diamond Dogs VFS
CO Forgotten Battles Division
http://www.248th.com

The_Community
12-21-2003, 09:51 PM
The B-239 will suffer damage in 100% pitch if you exceed about 500km/h. Reduce to 60-70% when in a dive. All other situations, use 100%.

I think P-40 can damage engine too if left in 100%.

AirBot
12-22-2003, 06:45 AM
Most allied aircraft have CSPs (Constant Speed Props) which maintain a selected RPM automatically. Good luck trying to overrev these suckers http://ubbxforums.ubi.com/infopop/emoticons/icon_wink.gif
I usually don't bother with prop pitch. I just keep it at 100% on Allied planes (max RPM) and on auto on German planes (I'm one happy puppy since the auto-pitch finally started working properly after 1.21 http://ubbxforums.ubi.com/infopop/emoticons/icon_smile.gif ).

<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>Originally posted by Vgamer_248th:
I read that PDF file, but a few things don't work correctly in the sim. Where it says that lowering the prop pitch will allow you to go faster, i just tried that and it doesn't work. 100% prop pitch and 100% throttle is close to max rpm (in the P47 at least) and if you lower the prop pitch you will slow down. The other thing is that i've never been able to overrev any allied aircraft, ever, even in a dive. Everything in the PDF makes sense and sounds correct, so is it just me then, or is prop pitch still not 100% correct in FB?

Vgamer
XO 248th Diamond Dogs VFS
CO Forgotten Battles Division
http://www.248th.com<HR></BLOCKQUOTE>

antifreeze
12-22-2003, 09:05 AM
VVS planes (in the game):
It depends what you mean by 'go faster'. It isn't a turbo boost. For clarity:
You can maybe get an additional 20-25kmph out of your plane flying level at around 3000m, by decreasing the prop pitch 5% (from 100%), waiting 20 seconds until your speed climbs slightly, and then when you are sure the speed has levelled off again, decrease it by another 5%. If at 90% the plane's engine can't handle shoving that much extra air behind it, the plane will slow down about 5kmph rather than speed up, so put the pitch back up to 95%.
The percentage of pitch that your engine can handle depends on your load-out and fuel, as well as varying from plane to plane. So it may be optimum at 100%, 95%, or 90%. Perhaps 85% in a light, unladen plane. You just have to play with it for a few minutes and keep watching for your top speed.
Return it to 100% for climbing. If you are diving to try to outrun an enemy, put it down to about 40%-60% for the duration of the dive.

What about flying at 5000m and above? Less air density. You need to push more air behind you to get the same performance experienced at lower altitudes. And because it is less dense, the engine is able to handle pulling a larger volume of air, so your optimum speed may now lay at a lower prop pitch percentage; 90%, 85%, or 80% depending on altitude, plane, loadout and fuel.

In the game, a player using CEM does have a small advantage regarding performance at varying heights over a player who uses auto.

OKL planes (in the game):
Don't fly them much, but you have to use prop pitch a lot more to keep the engine at its working load. Sometimes going as low as 30%. Hardly ever at 100%. The auto-prop and auto-mixture seem fairly good though; I think you would need to practise quite a bit to get a better performance than they can give you.

http://forgotten.battles.pulpo.co.uk/il2logo.gif

Maple_Tiger
12-22-2003, 10:01 AM
<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>Originally posted by Vgamer_248th:
I read that PDF file, but a few things don't work correctly in the sim. Where it says that lowering the prop pitch will allow you to go faster, i just tried that and it doesn't work. 100% prop pitch and 100% throttle is close to max rpm (in the P47 at least) and if you lower the prop pitch you will slow down. The other thing is that i've never been able to overrev any allied aircraft, ever, even in a dive. Everything in the PDF makes sense and sounds correct, so is it just me then, or is prop pitch still not 100% correct in FB?

Vgamer
XO 248th Diamond Dogs VFS
CO Forgotten Battles Division
http://www.248th.com<HR></BLOCKQUOTE>


Start this way:

1) German air craft and Allied air craft's prop pitch is differant.

For the allied planes 100% prop pitch is combat rpm. 75% is about cruize or about 2500RPM.

Also Alied planes have a Constant Speed Proppeler. The reg or governor will automaticaly change the prop pitch so it will stay at certain RPM. All you need to do it set it to a certain RPM and it will stay there.

What i do when im in a long coop is i lower the RPM down to 3000RPM(90% prop pitch). Keeps the engine cooler, saves on fuel and dosent over heat as quick. Shure youl will lose a few kmh but in real live they didnt run there planes at Combat rpm all the time lol. if Im just cruizen around ill sometimes change the prop pitch to 75%(2500RPM) and throttle back to 75%.

When i get into a fight i use Combat RPM(100% prop pitch)

Youl need to read up on it to fully understand it. Im lucky if i just no the basics lol. I bet i dont even know that lol.

Vgamer_248th
12-22-2003, 11:06 AM
Ok, that clears it up. Thanks for the reply antifreeze.

Vgamer
XO 248th Diamond Dogs VFS
CO Forgotten Battles Division
http://www.248th.com

ZG77_Lignite
12-22-2003, 11:18 AM
I disagree with what Antifreeze is saying. Vgamer, I believe you are correct (both historically and in FB).

Antifreeze, with a constant speed prop (which is used by most all American and VVS aircraft) you (the pilot) cannot directly affect Prop Pitch. When the On-Screen message says 'prop pitch' it is actually refering to an RPM setting (both historically and in FB). The prop is constantly adjusting itself (it's pitch) to compensate for speed and altitude. Again, in a CSP, changing 'prop pitch' only adjusts RPM governor, and the prop automatically attempts to maintain that RPM setting.

So, by setting a lower RPM (in a CSP) you are actually using less horsepower (as aircraft engines are designed to run at maximum horsepower at 'max' RPM) and therefor technically (at least historically, and imho in FB) you can go faster at '100%', or more specifically maximum engine RPM.

As a side note, there may be something to what Antifreeze is saying, if an engine is running above its 'max' RPM, horsepower begins to fall off again, thus if the pilot reduces the engine to the correct RPM, it may actually go faster. For example I believe the Mustang should run at 3000RPM (historically); going over this (and I believe FB does) should technically reduce horsepower slightly and thus top speeds. I do not know if FB models this in-depth of an engines horsepower curve.

P.S. Bf109's are a whole different story, so is the TB-3 bomber.

tttiger
12-22-2003, 11:43 AM
I have a feeling some of you have not flown all of the Allied planes very much. Particularly the lend lease pieces of junk http://ubbxforums.ubi.com/infopop/emoticons/icon_smile.gif

With a few of Allied planes you CAN blow the engine in a dive by running the RPMs past the redline. The Hurricane in particular. Nice they put the tach in easy view. I've blown P-39 engines several times. I fly both between 90-95% and drop pitch in dives. The P-40 is even more vulnerable. I use 85% for max RPM.

With the late war US planes and all the VVS planes, it's pretty hard to blow an engine, impossible in many. But I keep an eye on the Tach, anyway. Most US planes have a redline. The VVS planes mostly have a max RPM of 2,800 or 3,000, except the Sturmo which is about 2,100, the Chaika at 2,200 and the Rata (best plane in the game!) at 2,500.

(One of the things that is particularly confusing is that there is no such thing in RL flying as pitch percentage. I have no idea why Maddox set up a percentage system that doesn't exist anywhere else).

I never fly LW but my understanding is, historically, they used manual pitch control for takeoff and landing and put it in automatic for everything else including combat. I think that works in FB, too. But I do hear a lot of Hitler Youth complaining they have blown their engines in a fight.

Tailspin has done a wonderful job of putting all the data on spreadsheets. The link is below. Go to the Air-to-Air page and waaaaay down to the botton of the page and there are links to pdf spreadsheets on all aircraft. Tells you when to switch the supercharger, max RPM. I printed them out and keep them on my desk for quick reference when I fly a plane I have little experience in. Heres the addy and thanks, Tailspin:

http://mywebpages.comcast.net/Tailspin/index.htm (http://mywebpages.comcast.net/Tailspin/imdex.htm)

(I can't get that link to work -- this new format has some serious drawbacks. But cut and paste that addy into a new browser page and you'll go right to it).

Many other great resources on his pages as well.

Bottom line: Once you know the max RPM, either because there's a red line or from the data available in the game, just keep an eye on your tach as you would in a sports car. And listen to you own engine. The sound it is making will tell you what to do (it screams "slow down!" when you over-rev the prop http://ubbxforums.ubi.com/infopop/emoticons/icon_smile.gif)

Aloha,

ttt

"I want the one that kills the best with the least amount of risk to me"

-- Chuck Yeager describing "The Best Airplane."

[This message was edited by tttiger on Mon December 22 2003 at 11:18 AM.]

[This message was edited by tttiger on Mon December 22 2003 at 11:22 AM.]

gates123
12-22-2003, 01:01 PM
Naw... I fly the p-40 with 100% prop pitch and 99% throttle in combat and it wont overheat, once I redline it due to diving or going over 99% throttle I'll flip to 90-95% prop pitch and sometime cowl flaps to 2-6 depending on if I got a trailer on me. American planes really seem to have a high stress level on the motors you can really push them compared to LW A/C. They cool down quick if you cut your prop pitch to 90% or lower, but I'll usually disengage if I've been redlining it for too long to gain alt for more bnz fun.