The Scubster is a vehicle designed by Stephane Rousson, it is a pedal-powered submarine that allows you explore the ocean with more speed and greater range compared with scuba diving.
Thanks to its two ducted propellers mounted on rotating arms this underwater human-powered vehicle handles like a plane, going back and forth, side to side, up and down.
The aim of the "muscular propulsion submarine" is to reach 10kph of top speed while allowing longer and deeper explorations, since the Scubster can accommodate additional scuba tanks and lights.
Here is a demonstration of the Scubster
If it sees production (Stephane Rousson expects two more years of development) the Scubster could get an electric motor...