Duotone Diversity Magazine No.02 2020

Ralf, you built a kite prototype one and a half years ago implementing all kinds of innovations completely free of any technical limitations. What was your motivation for that? RALF With this ULW-study (Ultra Light Wind) my aim was to push the technological limits in kite-construction. Together with Hannes Knoll of our production facility at GSL Lanka, I’m in permanent contact with our raw material suppliers, who exclusively offer us their most innovative materials. These are non-commercial materials still in the testing phase and thus not in series production yet, which nobody else has access to. I wanted to put the current status of research and development in one prototype to test. TILL Innovative power is all about thinking outside of the box. Ralf built a kite out of materials that everybody said wouldn’t last. The kite is notoriously light, too light in fact. The shape was designed so that the kite would deform in only 12 knots. Ralf implemented features that are unthinkable of in a commercial kite. But that’s exactly how you bring innovations to life! By pushing existing boundaries you gain a vision and insight into what could possibly be done. In other words, by studying the shape of a super light kite that would not survive a hard impact on the water and also would instantly deform with a heavy rider you are able to gain valuable insights. You might take a few steps back to look for solutions for individual details or new materials that can be implemented into a new production run. Ralf, what kind of kite did you design? RALF I was curious to find out what the very lightest weight you could possibly build a 13m2 kite for was and what the minimal wind needed was to get the hydrofoil up and going. Due to the experimental materials and the construction, the ULW prototype weighs only 1.95 kg. And what did you find? What’s the lowest wind range? RALF With my weight of 82 kg and with the Duotone Carve 950 wing, I can get going in four knots in Langebaan, South Africa. The shape of the ULW prototype has been designed so that it has maximum launching abilities. Because of its large wingtip areas, I can reverse launch it with the backlines like a soft kite when it is lying on the leading edge both on the water or the beach. That works incredibly well. The ULW only needs two or three knots to smoothly come up above your head soundly aligned with the airflow. Once the kite is up, all is good: By moving the kite, you can now easily generate the lift that pulls you out of the water and onto your board. Keep it in the correct position in the power zone and off you go on your Foil Board. TILL Ralf is of the opinion that tube kites are more efficient than soft kites. Generally speaking, in the past the soft kites had more stability and performed better in light winds. However, that just changed with the ULW. In light wind this kite is more stable than any soft kite has been before. At Duotone we also have a soft kite model in our range, the Capa, and we continually prototype both types with our three designers – Kari is in charge of soft kites and Ralf and Ken are our tube kite specialists. As the market leader our intention and objective is clear: We want to engineer the best kite for the lowest possible wind range. Ultimately whether that is a tube or a soft kite remains to be seen. RALF Contrary to a soft kite, the weight distribution of a tube kite is ideal for the “lowest wind limit” requirement: A tube kite always has the tendency to fly forward without back stalling. A super light kite just sits there up in the air and doesn’t move. Besides, the handling of a tube kite is much better in light wind. Its turning radius is on the tip, with the soft kite it’s outside the tip. That’s why the ULW never feels like it’s about to fall out of the sky regardless of its position in the wind window. Also, soft kites are not ideal in terms of the lifting work, as 2 KNOTS The 13m2 ULW proto needs only two knots to be smoothly reversed launched and to sit there above your head soundly aligned with the airflow. 4 KNOTS Four knots is all it needs – fly a few sine curves and you’re up and riding away on a Foil Board. Newmaterials facilitate new shapes and innovative construction with wider ranges of use of kites. Has kite design moved up to the next rung on the evolutionary ladder in 2020? A conversation with Till Eberle, CEO of Boards &More, and Ralf Grösel, Kite Designer at Duotone in charge of the Vegas, Dice, Evo and Juice. Interview Bernd Zerelles Photos Daniel Deak Bardos, Toby Bromwich, Marian Hund T E C H N O L O G Y 80 81 T E C H N O L O G Y I N N O V A T I O N