It's great to know that most of the technology that is used in the "Flyboard" was created by Model Engineers and Aeromodellers.
Kurt Schrekling was amongst the first to build a successful miniature gas turbine using a compressor made from plywood strengthened its carbon fibre to stop it from disintegrating at the 100,000 or so revs that the small turbines develop the turbine blade was cut using a grinder and Dremel type tool to shape the blades..
Aeromodellers and electronics geeks developed small gyros to make the flying of model helicopters easier. They are taken for granted.
YvesRossy is worth looking up onYoutube, he starts on a wing with a couple of turbines attached and does some amazing flights.