Kymera powered body board gets electrified, approaches commercial release
By Darren Quick
September 26, 2012
It’s been over 20 months since we last looked at the Kymera jet-powered body board and it’s great to see that its creator, Jason Woods, has stuck with his dream of developing a compact and lightweight personal watercraft. In the time since our last story, Woods has continued to plug away in his garage refining the Kymera, which now sports a new hourglass shape, has made the switch from gasoline to electric power, and has attracted the interest of search and rescue (SAR) teams. Most importantly, the Kymera is nearing commercial availability, with Woods aiming for a release in 2013.
Woods came to the realization that his Kymera body board had applications beyond simply being a fun way to spend some time on the water after he was inundated with emails from rescue swimmers and lifeguards around the world in the wake of initial unveiling the Kymera. He realized that the Kymera, with its one-hour plus run time, would be even better suited to water rescue applications as opposed to recreational users that would be looking to run the device for longer periods. His creation would also be much cheaper and convenient than the boats and jet skis commonly used for rescue purposes.
Thankfully, Woods hasn’t abandoned his original vision of bringing the thrill of powered water transportation to the masses. The Kymera will still be targeted at recreational users, but the interest from the SAR arena gave him renewed inspiration to tailor a model to such users. It also prompted the switch from a gasoline engine to an electric motor, which he felt could be counted on to start much more reliably than a gasoline-powered engine.
The switch, which required a redesign of the Kymera’s conventional “jet drive” to maximize efficiency, also addresses noise and pollution concerns. The current electric motor outputs peak power of 3.4 kW and is powered by a lithium ion battery pack that will provide around an hour of use. The battery pack can be recharged from a standard wall outlet in around two hours and the whole board, including the battery, weighs in at 48 lbs (21 kg). This meets Woods’ aim of creating a personal watercraft that can be transported in a car without requiring a trailer and carried under an arm to the water.
But with electrical outlets not easy to come by on the shore, Woods has also developed a solar charging station for the Kymera. Measuring 4 x 6 feet (1.2 x 1.8 m), the charging station can fully recharge a Kymera in eight hours and is designed to be mounted on the roof of a lifeguard tower to ensure the board is always ready for action. Woods is also working on a combination roof rack/charger that can also pull power from a vehicle as it makes the trip to the water.
To take better advantage of the superior torque provided by an electric motor, Woods also modified the Kymera’s drive system. Woods was reluctant to provide specific details about the patent-pending system, but did reveal it is similar to the jet pump system used in the early Kymera prototypes, only far more efficient.
However, Woods hasn't ditched the fossil fuel option completely with a propane-powered model also in the works. While the current electric and propane models are largely identical and the majority of their components are interchangeable, the propane-powered unit boasts a three-hour runtime and increased power compared to the electric model.
The Kymera will come in two different sizes aimed at the recreational market, with each offering a choice of two different power options. A 5’6” (1.67 m) model will come with a choice of a 5 hp propane engine or a 2 kW electric motor, while a larger 6’6” (1.98 m) board has the option of a 10 hp propane engine or 3.5 kW electric motor.
The current electric models top out at around 18 mph (29 km/h), while the propane-powered models can reach speeds of up to 25 mph (40 km/h). As any go-karter will tell you, the sensation of speed is much enhanced when the rider is positioned closer to the ground – or, in this case, the water surface – so riders can expect to feel like they are shooting across the surface of the water much faster than they are.
Woods is also working on integrating an optional radio fence into these boards that could be operated by a parent or rental operator. This would limit the range of the board by reducing the throttle until the board returns to within a safe distance of the shore.
A third “Rescue” model aimed specifically at SAR users is a modified version of the 6’6” large board and boasts a high-end electric drive. The Rescue board can also be towed by rope or remotely controlled to bring distressed swimmers back to safety. With this in mind, the board features additional grab handles and its deck also doubles as a fold out deployable rescue sled. Its light weight would also allow it to be transported by truck or car, or even repelled over a cliff or lowered from a helicopter to swimmers in trouble.
Woods also teased us with mention of a “top-secret project” code named E.C.R.B. but is keeping details under his hat for now, revealing only that this board ups the power to 20 hp while reducing weight to 38 lbs (17 kg). Testing on this model is set to start “soon.”
Since we last looked at the Kymera, Woods has also given the board a new parabolic shape. Rather than just giving it a sexy hourglass figure, the new shape actually forms the board’s patent pending steering system. When the board is ridden at speed, the “hips” in the rear ride out of the water so that when the rider shifts their weight from side to side, the resistance of the board varies and the rider can carve through the water to change direction.
Woods says the new hull shape also controls the rate with which water is displaced by the board to act as a kind of shock absorber. As the water is displaced outwards in a controlled fashion, the board lays into the waves rather than slapping into them as is the case with a contemporary hull.
“This shape took years to perfect but has proven to be extremely stable and surprisingly agile requiring no other means of steering,” Woods says. “This reduced the systems complexity, further reducing the craft’s overall weight.“
Preliminary testing of the Kymera Rescue board has been completed with plans to move onto real world testing with SAR users in the near future. Woods expects to have the Kymera on the market for general consumers by (northern hemisphere) summer 2013 at a retail price of around US$5,000 for the base consumer model. However, he hopes that demand will allow him to increase volume and eventually get the price down to around $2,000. This would put the Kymera in closer competition to kayaks and paddleboards rather than much more expensive powered competitors, such as jet skis.
The electric Rescue Kymera bodyboard can be seen in operation in the video below. One of the biggest dangers we can see is people faking drowning just to get a ride on one.
Source: Kymera Body Boards
Update: This story was modified on Feb. 25, 2013, to correct the size of the solar charging station.