Zapata, a French jet ski (or waterski, depends on the web page !) champion, had already come up with the Flyboard, which was launched in 2011. Swimmers were sent skywards by a jet of water from a pack on their back.
Now a jet ski or similar is 18 metres behind the board, connected by a hose that couples under the board. This supplies the force so that the rider of the hoverboard can safely (for the jet ski driver) soar up to 10 metres upwards, propelled by a powerful jet. It won't be cheap -- about $6000 plus the cost of the jet ski. Here is the main drawing from the US patent, Device and system for propelling a passenger...
Yet another variation on the surfboard concept. So many twists have been done, mainly from Californians. Not in this case.
There is also a Maneuvering and stability control system for jet-pack patent application.
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