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Woke_Up_Dead
10-02-2008, 06:45 PM
Among the many good tables, guides, and advice related to engine management on this forum I can't seem to find one thing: a guide for the RPM "sweet-spot" of different airplanes. I usually try to keep the RPM's in the 2400-2700 range for all the planes I try to fly, but I suspect that some eninges have their optimum performance at slightly different speeds.

Does a table with such info exist? If not, what is your specific experience for particuar airplanes?

WTE_Galway
10-02-2008, 07:16 PM
Originally posted by Woke_Up_Dead:
Among the many good tables, guides, and advice related to engine management on this forum I can't seem to find one thing: a guide for the RPM "sweet-spot" of different airplanes. I usually try to keep the RPM's in the 2400-2700 range for all the planes I try to fly, but I suspect that some eninges have their optimum performance at slightly different speeds.

Does a table with such info exist? If not, what is your specific experience for particuar airplanes?


Go to the following link, create an account and download either Hardball's program or Il2 Wingman or possibly Il2 Compare or even all of them.

They all have databases of aircraft performance.


http://www.mission4today.com/index.php?name=Downloads&c=550

mortoma
10-02-2008, 07:24 PM
He is asking about peak power RPM. Neither Hardball's or IL2 Compare address that.

That said, in most planes it just seems like you get the most power at max RPM or manifold pressure, depending on whether the plane has a fixed pitch prop or CSP/auto pitch. Not realistic but I think Oleg took the easy way out on this one.

The only exception I have seen personally is the KI-27. This plane is an early fixed prop job and it seems to have more power at less than max RPM.

M_Gunz
10-02-2008, 08:38 PM
There is no single best for any plane even without including cruise and fuel savings.

Your best prop rpm is based on your plane, speed and power -- all together.
In fact, your best power setting also depends on plane, speed and prop rpm.
There is no simple "do this", just as in reality it takes skill and knowledge.

Woke_Up_Dead
10-02-2008, 09:21 PM
Originally posted by WTE_Galway:

Go to the following link, create an account and download either Hardball's program or Il2 Wingman or possibly Il2 Compare or even all of them.

They all have databases of aircraft performance.


http://www.mission4today.com/index.php?name=Downloads&c=550

Hi Galway, I was familiar with IL-2 compare, thanks for the links to the other two. I will check them out, but from mortoma's post it sounds like they won't give me the info I'm looking for here. The reason I ask is that I read somewhere (don't remember where now, but it may even have been in the IL-2 readme file), that different engines have different optimum rpm ranges, and I was hoping that someone already went through the effort of figuring out exactly what those are. But then maybe they all just work best at max rpm like mortoma says.

M_Gunz
10-03-2008, 04:21 AM
You can go to spitfireperformance.com and look at the performance charts for some planes there,
they list prop rpms for different test like top speed and climb. BTW, another variable is
altitude (it affects available power) though for the P-47 with turbocharger it's pretty
simple since speed is near constant.

Try diving well past level top speed with prop rpm at different settings and see what's best.

For accelerating .... just slamming the engine and prop to full may or may not be the answer
but if it doesn't turn out "like real" no matter how many 1000 times the same thing is done
then consider that in real the pilot knew the the plane before blaming the simulation for
not giving real results for unreal actions. NOT saying that you do! Just that with so many
here the next step is to declare the sim unreal and Oleg to be biased.