For slopememo
My plank has a pw75 profile. 1,2 mt wing span, 16 cm tip and 20 cm root.
It flies great even if it's so small. I did it with some spare foam sheets I had, just to try. I think to build next one about 3 mt wing span.
I have to check if will it be better use pw51 rather than pw75.... Don't know now.