Human-powered hydrofoil
Encyclopedia
A human-powered hydrofoil is a small hydrofoil
watercraft
propelled entirely by the muscle power of its operator(s). Human-powered hydrofoils may be driven by pedals, as in a hydrocycle
, by paddles, as in a Flyak
, or by bouncing, as in a trampofoil. Hydrofoils are the fastest water-based vehicles propelled solely by human power. They can reach speeds of up to 34 km/h (21 mph; 18 knots), easily exceeding the world records
set by competitive rowing
which stand at about 20 km/h. This speed advantage is achieved since hydrofoils lack a submerged body to provide buoyancy
, greatly reducing the drag
force.
. A common design for human powered hydrofoils consists of a large hydrofoil at the stern
end that is used both for propulsion and keeping the vehicle above the water, connected to a smaller foil at the bow
used for steering. Riders operate the vehicle by bouncing up and down on a small platform at the stern, whilst holding onto a steering column.
The Trampofoil is started and landed from the shore, or preferably from a jetty, and requires a bit of experience. When the Trampofoil is moving too slowly, it will sink, so no one has managed to get it started in the water. The Swedish and German navies have indicated their interest in the Trampofoil, but the problem with getting it started in the water continues to make it unsuitable for maritime use.
Originally developed in Sweden
, the inventor was not successful with its marketing and has discontinued it. There is a new product, Aquaskipper, being made in the USA, and some private developments in Europe and other places.
Hydrofoil
A hydrofoil is a foil which operates in water. They are similar in appearance and purpose to airfoils.Hydrofoils can be artificial, such as the rudder or keel on a boat, the diving planes on a submarine, a surfboard fin, or occur naturally, as with fish fins, the flippers of aquatic mammals, the...
watercraft
Watercraft
A watercraft is a vessel or craft designed to move across or through water. The name is derived from the term "craft" which was used to describe all types of water going vessels...
propelled entirely by the muscle power of its operator(s). Human-powered hydrofoils may be driven by pedals, as in a hydrocycle
Hydrocycle
A hydrocycle is bicycle-like watercraft. Power is collected from the rider via a crank with pedals, as on a bicycle, and delivered to the water or the air via a propeller. Seating may be upright or recumbent, and multiple riders may be accommodated in tandem or side-by-side...
, by paddles, as in a Flyak
Flyak
The Flyak is a hydrofoil adaptation to the conventional kayak. It uses twin hydrofoils designed to raise the hull out of the water to increase the speed. Speeds of up to 27.2 km/h can be achieved on calm water....
, or by bouncing, as in a trampofoil. Hydrofoils are the fastest water-based vehicles propelled solely by human power. They can reach speeds of up to 34 km/h (21 mph; 18 knots), easily exceeding the world records
Rowing World Records
The Rowing World Records are the fastest times set over the international rowing distance of 2000 m. They are believed to be correct as of November 2011.-On Water Records:...
set by competitive rowing
Rowing (sport)
Rowing is a sport in which athletes race against each other on rivers, on lakes or on the ocean, depending upon the type of race and the discipline. The boats are propelled by the reaction forces on the oar blades as they are pushed against the water...
which stand at about 20 km/h. This speed advantage is achieved since hydrofoils lack a submerged body to provide buoyancy
Buoyancy
In physics, buoyancy is a force exerted by a fluid that opposes an object's weight. In a column of fluid, pressure increases with depth as a result of the weight of the overlying fluid. Thus a column of fluid, or an object submerged in the fluid, experiences greater pressure at the bottom of the...
, greatly reducing the drag
Drag (physics)
In fluid dynamics, drag refers to forces which act on a solid object in the direction of the relative fluid flow velocity...
force.
Trampofoil
Trampofoil, also known as Hydro-bike, HydroSlide, Hydrothopter or Aquaskipper, is a light, one-person hydrofoilHydrofoil
A hydrofoil is a foil which operates in water. They are similar in appearance and purpose to airfoils.Hydrofoils can be artificial, such as the rudder or keel on a boat, the diving planes on a submarine, a surfboard fin, or occur naturally, as with fish fins, the flippers of aquatic mammals, the...
. A common design for human powered hydrofoils consists of a large hydrofoil at the stern
Stern
The stern is the rear or aft-most part of a ship or boat, technically defined as the area built up over the sternpost, extending upwards from the counter rail to the taffrail. The stern lies opposite of the bow, the foremost part of a ship. Originally, the term only referred to the aft port section...
end that is used both for propulsion and keeping the vehicle above the water, connected to a smaller foil at the bow
Bow (ship)
The bow is a nautical term that refers to the forward part of the hull of a ship or boat, the point that is most forward when the vessel is underway. Both of the adjectives fore and forward mean towards the bow...
used for steering. Riders operate the vehicle by bouncing up and down on a small platform at the stern, whilst holding onto a steering column.
The Trampofoil is started and landed from the shore, or preferably from a jetty, and requires a bit of experience. When the Trampofoil is moving too slowly, it will sink, so no one has managed to get it started in the water. The Swedish and German navies have indicated their interest in the Trampofoil, but the problem with getting it started in the water continues to make it unsuitable for maritime use.
Originally developed in Sweden
Sweden
Sweden , officially the Kingdom of Sweden , is a Nordic country on the Scandinavian Peninsula in Northern Europe. Sweden borders with Norway and Finland and is connected to Denmark by a bridge-tunnel across the Öresund....
, the inventor was not successful with its marketing and has discontinued it. There is a new product, Aquaskipper, being made in the USA, and some private developments in Europe and other places.