February 10, 2009 The Foiljet MR1 is a new personal watercraft concept that takes the best features of a motocross bike and jetski, throws in two hydrofoils plus a silent, energy efficient electric motor to create what would have to be a surefire recipe for outrageous fun. The design looks something like a motocross bike, but instead of wheels there are beams with small hydrofoil wings mounted at the ends that can be raised or lowered. The concept would use a 15 kW (20 hp) electric motor housed at the end of the rear beam with its instant electric torque lifting the craft out of the water to become "foil borne".
To cope with shallow water the beams can be raised at the flick of a switch. The electric motor runs off a 48V battery that should see three hours of full load running with the possibility of a theoretical 10 min recharge time.
While still at the purely concept stage Matt De Bellefeuille & Robert Vandenham have come up with an original design that most definitely deserves to reach the prototype stage.
The designers have selected a T-shaped fully submerged foil system which, while not affected by surface waves is not self stabilizing, so it needs constant adjustment of the angle of attack of the front foil to keep the craft level with the surface. Front foil angle adjustment on the Foiljet MR1 is made manually by what would conventionally be the clutch lever on a motorcycle. In larger applications this sea-keeping function is automated with a computer system that measure either surface height or pitch and roll to make constant fine adjustments to the front foil.
Hydrofoils produce relatively no wake and electric propulsion is near silent, so if the Foiljet MR1 makes it into production it may allow current laws against jetski’s on inland water ways to be relaxed around residential areas.