Originally Posted by peterlngh
To put it very simply...
A small prop spinning fast will help a plane dive fast while a big prop spinning slower will make a plane climb fast. Since the motor in a powered glider is just a means to gain altitude fast, big slow props are better. Mostly it's due to blade area.
What's more important on a prop - the length or the pitch? If you get a bigger/larger motor with a higher KV then you want a smaller prop, right? When you get a smaller prop, what's more important - a smaller length or pitch?