Yeah they are fixed wing and external propeller. I think they make them "in house" with their own equipment. The ones i saw loked like they were made of regular styrofoam. A little clunky but they flew. I also know of someone who has a foam one like the foam you used but the wings are still fixed its abut 2/3 the size of the sv. From what i see around here the SV-51 would be considered LARGE for a park flyer. The largest park one i have seen is 1/32 scale at the most.