How does the aquaskipper work?

Question

I've read the basic stuff from the makers but am looking for more info: how does the back foil tilt back up after an impulse, why can't it go faster than it does (drag must be very low so you should be able to accelerate above 25 kph)...

Answer 1

Every time you jump, the force of your weight compresses the fiberglass spring, causing the back foil to change its angle. From the same impact of your jump, the angled back foil is pushed downward to generate the propulsion.

The front foil is locked to a constant height in the water by the skimmer, which planes on the surface of the water.

Even though hydrofoil's have very little drag, the amount of thrust you can generate via flapping wing propulsion is quite limited.  Pedal or paddle power is so much more efficient.  Either way, its rated 17mph speed seems pretty fast to me, but man, does all that jumping up and down look like a serious work-out.