Just getting started with my Kadet LT-40.......

using an OS .46 AX
with various size APC props....

any reason why I can't use a 3 blade prop....?
and if I can, what size....

I just really like the looks of them..

is there a reason I "shouldn't" use a 3 blade????

Just curious
Thanks!!!
Exeter

There are positive and negative things about using a 3 blade on your LT-40.

On the plus side, they do look nice, even unusual.
They're less efficient, in the small sizes we use, and that's good for a trainer. Keeps it a little slower, more time to react, while providing a good load for the engine, to keep the glow plug warm, less stalling.

On the negative side, they're expensive, and sometimes we break a prop on landing. And, the spinner costs a bit more.

Welcome aboard, and enjoy your plane!
Dave Olson

For models, there are no positive things about a 3-b prop, except ground clearance & appearance. Your LT 40 has ample ground clearance, so use a 2-b prop --- 11-5, 11-6, or 12-4. The 3-b will give you poorer flight performance from every aspect.