Introducing our Bungee 2.0 hydrofoil launching - pulling - towing system. Lot's of fun, and enough towing power to get us all up on a prone foil board, I weigh about 200 pounds and there was enough pull for me to fly. The two big additions to our bungee are the hand crank winch for pulling back the bungee and a quick release attachment.
We used a 16 pound anchor I found on craigslist. Some of the recommendations are at minimum a 25 pound Danforth anchor. Our bungee in this video ended up being 100 feet, we made our own braiding three lengths of 3/8" thick 100 foot bungee cords. We winched the bungee back far enough that the anchor gave way a few times. When it did the anchor would move through the water relatively slowly, maybe 20 feet or so and then settle on the bottom, we still had tension on the bungee but not a very much. Our setup has enough weight to it that there is little chance of the bungee or anchor from flying back towards us, we felt safe even when the bungee was really tight and we could barely crank it back any further.
We also had an inflatable buoy to let us know where the anchor was and hopefully serve as a barrier if the anchor came loose. The other function of the buoy was to keep the bungee up and mostly out of the water. My thinking was that a raised straighter pull would help us lift the foil, whereas a downward underwater pull might make it harder. The buoy also helped other folks on the water see us and our bungee line and go around it. Using a longer rope (100 feet) between our buoy and the anchor helped the anchor stay put, so the anchor had a more horizontal pull rather than being pulled slightly up.
The trickiest part of our first Bungee test was getting up on the board and staying balanced in he first few seconds while launching the bungee. Water starting seemed to difficult, so we set a 2x4 board in between two ladders and used this as our "dock" starting platform. I suspect some kind of floating "dock" would work, maybe an inflatable inter-tube or raft.
One of my motivations for this is to find a human powered affordable way to practice and have fun foil surfing.
These sessions were on a smaller wing (around 120), prior to the winch addition on a bigger wing (160) lift was much easier. So I suspect a bigger wing on this bungee setup would enable some long rides, and give newbies another way to try foiling.
I hope this helps!
And below is a members only longer version of this how to video, 10 minutes and 10 seconds:
Also available for members are more video tips and info on our setup and some details that allowed us to have more pulls faster and easier: