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vlieg1982
02-08-2006, 03:06 PM
Hello all ,

a have a question of Prop pitch , of some airplanes in the game ,for example the Heinkel 111,
you rise the pitch to 100 / 90 % no deal, engine runs smooth.
but why fall the pitch each time back to 30% and cut out the engine performance ?

Chuck_Older
02-08-2006, 03:54 PM
I don't know, I have never flown the He 111. I guess I'll have to try it

Prop pitch is a little odd in the sim.. I don't know much about the type of propeller on the He 111 we have, but it is possible that there are really only two settings: "fine" and "co****". Of course, we have to choose a setting 1-100%... many aircraft, especially early in the war, had only two pitch choices. I wonder if this is the issue in this case

Chuck_Older
02-08-2006, 03:57 PM
OK, this is <span class="ev_code_YELLOW">stupid</span>

if I want to discuss propeller theory, on a forum dedicated to a flight sim, I'm gonna have to use the word
"c o a r s e"
once in awhile. I can type the word '***' until I'm blue in the face, but I can't use the term that's the opposite of 'fine' concerning propeller pitch. That's friggin stupid http://forums.ubi.com/groupee_common/emoticons/icon_mad.gif

dravisar
02-08-2006, 04:00 PM
ROTFL it censored A R S E

Akronnick
02-08-2006, 05:03 PM
[pounds head on desk]

someone needs to get thier head out of their ***.

It will make it easier to bugger them!!! http://forums.ubi.com/images/smilies/784.gif

Akronnick
02-08-2006, 05:08 PM
Okay back to topic.

one reason you would want to decrease rpm is when you are in a power off situation, say you want to descend but not reduce airspeed, lower rpm will give you less drag and allow for a more effiecient glide.

dbillo
02-08-2006, 05:11 PM
Originally posted by vlieg1982:
a have a question of Prop pitch , of some airplanes in the game ,for example the Heinkel 111,
you rise the pitch to 100 / 90 % no deal, engine runs smooth.
but why fall the pitch each time back to 30% and cut out the engine performance ?
At 100% pitch, the propeller blades are flattest and meet the air at a small angle. When you change the pitch to 30%, the angle of the blade increases. As you increase the propeller blade angle, it becomes harder for the engine to spin the propeller, because it creates more air resistance.

There, I did it without typing a r s e!

Swivet
02-08-2006, 06:09 PM
What's the advantages/disadvantages of Prop Pitch in this sim..i never use it.

Jaws2002
02-08-2006, 07:39 PM
Originally posted by dbillo:
<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by vlieg1982:
a have a question of Prop pitch , of some airplanes in the game ,for example the Heinkel 111,
you rise the pitch to 100 / 90 % no deal, engine runs smooth.
but why fall the pitch each time back to 30% and cut out the engine performance ?
At 100% pitch, the propeller blades are flattest and meet the air at a small angle. When you change the pitch to 30%, the angle of the blade increases. As you increase the propeller blade angle, it becomes harder for the engine to spin the propeller, because it creates more air resistance.

There, I did it without typing a r s e! </div></BLOCKQUOTE>


This is wrong for most planes. This only applies to BF 109 (variable pitch). For the rest of the planes (constant speed propeler) you change the RPM. what you see as prop pitch is actually % fron the maximun RPM. You change the RPM and the propelor governor changes the pitch to meat the required rpm. So in HE-111 if you set prop pitch to 30% you set the engines RPM to 30% from the maximum RPM and the governor is adjusting the pitch for that RPM.

Heavy_Metal1982
02-08-2006, 07:50 PM
http://forums.ubi.com/images/smilies/88.gif

dbillo
02-08-2006, 08:01 PM
Jaws, I understand what you are saying...that there is a governor involved. I would say that I wasn't completely wrong, though, since the effect is the same...i.e. the propeller pitch changes and that, in turn, changes the engine rpm. The governor, however, will continue to alter the pitch as required to maintain the engine at the set rpm (within limits).

vlieg1982
02-10-2006, 07:31 AM
am understanding the prop pitch theory but my problem is : for example the Ju-88A4 from the new patch , why does the game (or plane) reset the prop pitch again and again to 43% if a increase it to 100% the plain rest it to 43% , and it result in a plain crash , is ther samphing wrong with my game profile or wat ?

WOLFMondo
02-10-2006, 07:35 AM
Noticed how the default lettering on the Mosquito is A R S?

Nigel_Woodman
02-10-2006, 08:39 AM
Here's how a constant speed propeller works. This info does not apply to other types of variable pitch props as found on earlier WW-2 aircraft.

The prop lever controls the RPM at which the propeller governs the engine speed. If for example the RPM is set to 2400, no matter what the airspeed, the propeller will change pitch to keep the engine RPM at 2400 (assuming no reduction gearing is involved). As airspeed increases, the prop pitch will increase, but the RPM will remain the same. As airspeed decreases, the prop pitch will decrease, but the RPM will remain the same.

Why would a pilot want to change RPM of the engine if the prop is working at it's most efficient pitch all the time? The answer is that at some RPMs, the engine will deliver more power, and at other RPMs, it will be more efficient. For example, for the R-1820, an engine with which I am familiar, and which I think was used in the B-17, cruise RPM is something like 1800, climb RPM 2400, and max power RPM 2600 or maybe 2800 (memory fails).

Another consideration is what's called "overboost" which is not simulated in the game. At low RPM if the throttle is opened all the way on a supercharged engine, the engine will quickly blow up. Higher engine RPMs are required to handle the increased pressure. In RL, going to 50% pitch with the throttle all the way to the firewall would blow the head off most high performance recip engines.

Jaws2002
02-10-2006, 09:00 AM
Originally posted by vlieg1982:
am understanding the prop pitch theory but my problem is : for example the Ju-88A4 from the new patch , why does the game (or plane) reset the prop pitch again and again to 43% if a increase it to 100% the plain rest it to 43% , and it result in a plain crash , is ther samphing wrong with my game profile or wat ?

Do you have the prop pitch on a slider? Did you check the slider positiom at take off?
I think your problem is in the controls area.Check if you have both engines selected and check your controls for prop pitch. The problem should be somewhere there.
Sounds like you have a slider for prop pitch set to 43% that you forgot about.

My Ju88 works perfect, I have the prop pitch on a slider on the throttle.

vlieg1982
02-10-2006, 12:59 PM
Originally posted by Jaws2002:
?

Do you have the prop pitch on a slider? Did you check the slider positiom at take off?
I think your problem is in the controls area.Check if you have both engines selected and check your controls for prop pitch. The problem should be somewhere there.
Sounds like you have a slider for prop pitch set to 43% that you forgot about.

My Ju88 works perfect, I have the prop pitch on a slider on the throttle.


Thanks Jaws ! it was the slider on my keybord,
that was the problem ,

Jaws2002
02-10-2006, 02:52 PM
Cool. Now go blow up something. http://forums.ubi.com/groupee_common/emoticons/icon_biggrin.gif

russ.nl
02-10-2006, 03:49 PM
I use the proppitch for gliding down on a strafing run and to get the engine to run smooth. Usely when you run your engine at a high power it gets some kind of ritm. So I adjust the power and proppitch so it runs smooth. I also use it to get the gauges in the green. You can see this very well in the b-25.

Is proppitch something you can or hear about your engine or see at the gauges?
Or is it something that you have to learn for every a/c at every speed and alt.?