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!