109 prop pitch (rpm) and the supercharger

[Robo.]

Originally Posted by macro

so RPM doesnt stay constant if pilots increase RPM at higher alts for more speed?

Of course it does. Best thing of keeping something unchanged is to change it, obviously.

I am trying hard to figure out why is this happening - reading this:

In a selectable pitch propeller, this is done manually by coarseing the pitch to maintain a constant rpm.

...I reckon Crumpp is not aware of the fact that by coarseing the pitch in the 109 the rpm drops accordingly.

Crumpp wake up!

[Crumpp]

I reckon Crumpp is not aware of the fact that by coarseing the pitch in the 109 the rpm drops accordingly.

Not if you are using it right.

Rpm will drop as the speed increases and the propeller begins to drive the engine. Coarsen pitch as the rpm begins to drop to maintain it.

[macro]

Originally Posted by Crumpp

Not if you are using it right.

Rpm will drop as the speed increases and the propeller begins to drive the engine. Coarsen pitch as the rpm begins to drop to maintain it.

eh?

rpm will increase as speed increases not drop, until you adjust pitch, at least my 109 does anyway lol

[Crumpp]

rpm will increase as speed increases not drop, until you adjust pitch, at least my 109 does anyway lol

OOPs, yes it should increase and you coarsen the pitch to keep rpm constant.

You must maintain that rpm setting at a constant rate.
- You must pursue that (efficient) rpm setting at a continuous rate (by manual pitch)

Correct.

They are changing rpm to an overboost condition, adjusting pitch to maintain the overboost rpm setting, and then reducing it let things cool down.

When they reduce rpm, they also adjust the pitch to maintain the new rpm setting as the aircrafts speed changes.

[Crumpp]

NZtyphoon

Maybe it is time for your stability and control documents.

You know, the ones with the picture of the Spitfire and the general comments that have nothing to do with the Spitfire?

[kohmelo]

Originally Posted by Crumpp

Is that hard to understand or something? It must be as we have multiple pages on this simple concept.

Originally Posted by Robo.

...I reckon Crumpp is not aware of the fact that by coarseing the pitch in the 109 the rpm drops accordingly.
Crumpp wake up!

I really start to believe we are losing something in translations or then I am only one. (Honestly I needed to take dictionary on my hand)

You must maintain that rpm setting at a constant rate.
- You must pursue that (efficient) rpm setting at a continuous rate (by manual pitch)

Its like Bouy rocking after a wave.
Wave hits Buoy -> it must maintain its stability at a constant rate

I really believe that most of us are speaking of the same thing but everybody have their eyes fixed on one single point of this issue

[ACE-OF-ACES]

Originally Posted by kohmelo

I really start to believe we are losing something in translations or then I am only one.

Not really, Only thing that makes it hard to read is Crumpp's atempt at trying to redefine the word 'maintain'.. Clinton would be proud!

[NZtyphoon]

Originally Posted by ACE-OF-ACES

Not really, Only thing that makes it hard to read is Crumpp's atempt at trying to redefine the word 'maintain'.. Clinton would be proud!

Perhaps this might help



is different to



but, rather than keeping things



Crumpp likes to change context and words to maintain whatever argument he thinks he has.

[ACE-OF-ACES]

Originally Posted by NZtyphoon

Crumpp likes to change context and words to maintain whatever argument he thinks he has.

Bingo!