I don't think there is an actual range for wingspan for park flyers or any other type aircraft. Usually, when the manufacturer says "park flyer" then that's what it is. For instance, you can't say 36 inches because the Little Something Extra has that wing span but is not a park flyer, yet a foamie that is very light, with a 36 inch wingspan may be considered a park flyer and designed to fly in more confined spaces (ball parks, soccer fields, and so on) than something that really needs a runway. A 40 size glow trainer is a trainer as is a 60 size glow trainer. Both are glow powered trainers, but one is larger than the other.. a wider wingspan and a bigger engine.

CGr.