ORIGINAL: flycatch
I have read most of the post concerning prop size and all of the poster have neglected to realize that prop clearence is the driving factor in this airplane. Using the assumption that this is a typical trike gear trainer style model most 11" and 12" diameter props are ill suited for ground clearence. I would recommend a 10x6W for this airframe.
In my post I did mention that I changed the main and nose gear to go with the larger prop diameter. I did fail to mention that you will need to do this for the ground clearance or you had better never land hard as the music wire will give and then instant prop strike (Ask me how I know).