RPM and manifold menaging in p51 and in f4ux

[lulu]

Let's discuss pls.

 

[olds442]

Let's discuss pls.

 

RPM= prop pitch

manifold pressrue: is the air entering the engine

[lulu]

That's quite known. TY

Which value for both during ACM?

Some values seem better then others or not?


 

[colmbo]

Maximum RPM with Maximum Manifold pressure will give you maximum power.

Real life you avoid very high manifold settins with reduced RPM to keep pressure reasonable within the cylinder...that isn't modeled in AH.

[lulu]

"Real life you avoid very high manifold settings with reduced RPM to keep pressure reasonable within the cylinder...that isn't modeled in AH."

CC.

I think that we have something like that in AH too with different options for different planes, because
under some circumstances some planes seem to work better with less or much RPM and less or much manifold.

Is it my impression only?


  

[MachFly]

"Real life you avoid very high manifold settings with reduced RPM to keep pressure reasonable within the cylinder...that isn't modeled in AH."

CC.

I think that we have something like that in AH too with different options for different planes, because
under some circumstances some planes seem to work better with less or much RPM and less or much manifold.

Is it my impression only?


  

What do you mean by "better"?
You get higher fuel economy with loser RPMs and lower MP, but if you want power you want max RPMs & MP.

[Soulyss]

The only time I touch the RPM controls is to increase fuel duration between combats.  During a fight I leave RPM maxed out, adjusting the throttle (manifold pressure) can be desirable depending on the situation.

[Wiley]

One other effect I thought was in here-  If you're dead stick and gliding, doesn't lowering RPM to the bottom decrease drag?  Or is my old nemesis the placebo effect once again making me see things that aren't there?

Wiley.

[GNucks]

One other effect I thought was in here-  If you're dead stick and gliding, doesn't lowering RPM to the bottom decrease drag?  Or is my old nemesis the placebo effect once again making me see things that aren't there?

Wiley.

Yes, I believe that is the case. There was a thread about ideal glide speed and conditions to achieve maximum distance not too long ago. The best things you can do for yourself if you know you're going to be deadstick before you can reach friendly tarmac is to start climbing as high as you can before your engine gives out. Then you lower your RPM's and shut off or engine at a slow enough speed that the prop stops rotating completely (not windmilling). Yesterday I was able to glide all the way from Rook City to Bishland using these procedures.

[321BAR]

Yes, I believe that is the case. There was a thread about ideal glide speed and conditions to achieve maximum distance not too long ago. The best things you can do for yourself if you know you're going to be deadstick before you can reach friendly tarmac is to start climbing as high as you can before your engine gives out. Then you lower your RPM's and shut off or engine at a slow enough speed that the prop stops rotating completely (not windmilling). Yesterday I was able to glide all the way from Rook City to Bishland using these procedures.

agreed. by lowering your RPMs and feathering your prop you do glide better. no matter which plane you use <S>

[MachFly]

One other effect I thought was in here-  If you're dead stick and gliding, doesn't lowering RPM to the bottom decrease drag?  Or is my old nemesis the placebo effect once again making me see things that aren't there?

Wiley.

That is correct but if you manage to stop the prop completely your glide distance will significantly increase.

Read the first post in this thread: http://bbs.hitechcreations.com/smf/index.php/topic,308176.0.html (specifically pay attention to the 7th test)

[RTHolmes]

I think that we have something like that in AH too with different options for different planes, because under some circumstances some planes seem to work better with less or much RPM and less or much manifold.

Is it my impression only?

quite right. eg. the spits' merlins give much better cruise endurance at reasonable speeds if you keep full throttle and wind the rpms down until you reach the desired boost (just like the real thing.) this does not work well in a jug (just like the real thing). I very much doubt many people fly by-the-book this way, but its impressive that its modelled so you can

I'd suggest picking up a copy of the pilot's notes for your favorite aircraft and trying the by-the-book settings for economical flying, my guess is they will generally work.


if you mean settings while in combat, always use max rpm. this gives you max thrust at full throttle, and max drag to decelerate the aircraft when off the throttle