When and What do I use prop pitch for?
#16

Guys,

Wow! Thanks for all the info. I am a bit of a laymen when it comes to the prop pitch but I get it (for the most part. I would like to explore the different optimal pitch/Rpm ranges for the different planes in Il-2.

Thanks again
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#17

Hi all

I always use prop pitch when I fly the 190. I assume the additional RPMs I get on 100% pp (200-300 from memory) translates into more power= speed and climb. I think I remember doing some really basic speed tests and IAS did increase. I use 80% or 70% for cruise on the assumption that less RPM = less heat and therefore an ability to fly faster for longer. I think there is some basis for believing this but I'm not absolutely sure of it. If anyone actually knows I'd be interested to hear about it. I also use 80% pp when I do extended dives but I'm not sure that it does much other than maybe help to cool the motor. I haven't done any testing based around altitude but from what I can see, going from 100% to 80% PP results in a reduction in speed. I find this a bit surprising but that seems to be what happens. I have heard people say that pp isn't modelled correctly in the game but I'm not qualified to make that sort of judgement. My experements with pp on other aircraft have met with less success. No change in performance with the Spit and almost certain engine failure (over reving) with the 109. The D9 is an interesting one and I'm still experementing with it. You do get more power when combining 100% pp with WEP and you can utilize this extra power for hard climbing - but you have to be very careful not to over rev as the motor will fail within seconds of exceeding 3500 rpm. In a combat situation it really doesn't seem to be worth it because invariably you will blow your motor. On one occasion I used the 100% pp/WEP combination at about 7 or 8 K and I think it worked ok in level flight. Not sure why that would be given the rarefied air at that alt. but I 'm fairly sure it worked. The only think I think I can say with absolute confidence is that the 190 works a bit better with pp than without, and frankly, I think the 190 needs all the help it can get. :wink:

cheers
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#18

I thought the Fw190 had an automatic prop pitch?
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#19

Yes, the 190 series had an auto-pp feature in RL but this could be over-ridden by the pilot. The over-ride/manual change device is situated on the throttle.

I don't know if LW pilots relied on auto settings in combat or whether they preferred the greater level of control that was probably available on manual. My suspicion is that when things got really hairy, you'd want all the control and power you could get.

In the sim world, the reality is that you do get a bit more power if you manage pp yourself (on the 190). It also, in my view, adds to the fun.
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#20

terrorfleiger Wrote:Hi all

I always use prop pitch when I fly the 190. I assume the additional RPMs I get on 100% pp (200-300 from memory) translates into more power= speed and climb. I think I remember doing some really basic speed tests and IAS did increase. I use 80% or 70% for cruise on the assumption that less RPM = less heat and therefore an ability to fly faster for longer. I think there is some basis for believing this but I'm not absolutely sure of it. If anyone actually knows I'd be interested to hear about it. I also use 80% pp when I do extended dives but I'm not sure that it does much other than maybe help to cool the motor. I haven't done any testing based around altitude but from what I can see, going from 100% to 80% PP results in a reduction in speed. I find this a bit surprising but that seems to be what happens. I have heard people say that pp isn't modelled correctly in the game but I'm not qualified to make that sort of judgement. My experements with pp on other aircraft have met with less success. No change in performance with the Spit and almost certain engine failure (over reving) with the 109. The D9 is an interesting one and I'm still experementing with it. You do get more power when combining 100% pp with WEP and you can utilize this extra power for hard climbing - but you have to be very careful not to over rev as the motor will fail within seconds of exceeding 3500 rpm. In a combat situation it really doesn't seem to be worth it because invariably you will blow your motor. On one occasion I used the 100% pp/WEP combination at about 7 or 8 K and I think it worked ok in level flight. Not sure why that would be given the rarefied air at that alt. but I 'm fairly sure it worked. The only think I think I can say with absolute confidence is that the 190 works a bit better with pp than without, and frankly, I think the 190 needs all the help it can get. :wink:

cheers

viewtopic.php?t=11419

Low pitch or fine pitch\high rpm = max horsepower and manifold pressure but also maximum wear and tear on the powerplant. To reduce these effects after takeoff the rpm,s are reduced by adding more blade angle to the propeller and the manifold pressure is reduced by slightly closing the throttle. This is standard procedure when using an aircraft to get from point A to point B. Most flight manuals will give you a throttle and prop setting for both climb and cruise. Under ACM you should probably have your prop at the high rpm setting so you can pull max horsepower when jockeying the throttle. Mixture is used to acheive higher effeciency as you climb in altitude since a slightly leaner mixture will develop more power but as you lean the cylinder head temps start to climb so this is normally monitored as you reduce your mixture. Whenever you are at full throttle you should probably be at full rich or autorich as the additional fuel helps to cool the cylinder heads. On some WWII aircraft is was also necessary to shift your blower into high as you passed through a certain altitude as this also controls your manifold pressure. Feathering turns the prop blade in the direction of flight and is used to minimize the drag of a dead engine. In a normal configuration the prop blades would be large airbrakes on the front of the aircraft when the prop is not turning.

I guess the answer would be stay in the 8 to 10 range. Personally I mapped the pitch change functions to my left and right mouse buttons. Put it at 10 for takeoff. Pull the prop back to 9 for climbout and back to eight for cruise. I think under combat I would probably just leave it at the high rpm setting. Thats where you are going to pull the most hp out of the power plant and acheive your best rate of climb. The 51 in the game will give a 1500 rpm drop at max manifold pressure which is probably a bit high. Probably should be 600 to 800 rpm. I would need to go look at the TO to see what drop should be at max manifold pressure. You can see by the figures below you are normally working in a 700 RPM range depending on what youre doing with the aircraft
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