Amazing Underwater Flight!

I've been looking at the pictures trying to figure out how it goes together and what makes it work. How you get it to reverse seems so obvious now, I feel foolish I asked the question. I've never picked one up, I just read about it on the web this week. From what I've seen and read, I want to try one. I've asked Innerspace how much they cost with a view to buying one. Although after reading your post, I'd guess unless there's one or two in the back of their stores somewhere, theres not likely to be one for sale, so I expect if I want one I better figure out how to make one.

I was wondering how the foils were retained on the axle. I guess I know now.

Instead of damaging the wood, how about two fishing rod eyelets bound back to back, to the tubular shaft. For quick change forward/reverse I wondered if I could string the foils with light bungy cord and fasten it with a dog lead clip top-side eyelet/ forward. To change direction release and pass the bungy over the foil and fasten it base side for reverse. If it works, I'm not sure about the foil security. If I wasn't happy with my two hands, I might try using one of those cord clips most fleece jackets and outdoor clothing have and slide it up to the foils first.