OK, so the inside fairing of the beams consists of the tender hulls. So the tender cat needs to be assembled for use each time. I guess the tender beams are tubes wrapped in trampoline tissue and kept in the box parallel to the ww hull. Could use the light fighter beach cat in a smaller Steinar proa configuration for quick setup and double use the wing sail of the cat as a mizzen of the sailwing proa - Thanks, Fedor.