Instead of kicking, PowerSwim calls for a kind of undulation as its hinged foils pivot up and down. Similar to the way a dolphin or tortoise pumps its fins, this motion generates both lift and thrust. And while artificial fins operate within the swimmer’s own wake (they form a kind of expanding cone, starting at a swimmer’s shoulders), the PowerSwim’s lead foil–or propulsor foil–sweeps through the water just outside that wake.
When used properly, the device allows swimmers to cover a given distance up to 150 percent faster than with fins, while using the same amount of energy.
The idea is to get swimmers such as special operators to shore more quickly with less effort. The units may be fielded as early as next year.