Kite-boards -- more about
14 November 2010
Speaking of kite-boarders frequently keeping it under control, I recommend a visit to You Tube and search "Rob Douglas record run 50.54" and "Taro Niehaus SA record run 8th Oct". Note that in both cases the runs end in impressive crashes; I understand that Douglas did break his wrist in a later crash (by then he had upped the record to 55.65 knots).
When we look at a kite-boarder powered up (either on video or a still photo) we can see the relationship between the airfoil (kite) and the hydrofoil (board). That relationship is very close to what I've been advocating for years with Sailien. Their vertical mis-alignment of the sailing forces is about 2 feet (the distance the control lines are above the board). That unbalance is compensated by the sailors' weight hiked out to windward and heavier sailors will have an advantage. Additionally, the sailor has to hold all the power of the kite and transfer it to the board, so strength is a major factor in high-power conditions.
For those of you who have had doubts about the workability of a "force-aligned" craft, such as I have been advocating with Sailien, take note of the above. My view at this time is that windsurfers are no longer competitive because their vertical misalignment is too great (the distance from the center of effort of the sail to the board).
Kite-boarders could easily increase their speed (with no increase in wind-speed) by figuring out how to attach the kite control lines to the board, so the pull is directly at the board. By doing that, weight and strength would no longer be an issue and all the power of the kite could be applied to the board at all times. Naturally some means of control and balance would have to be worked out. The next step would be to enclose the kite-sailor's body in a streamline fairing and kite-boarders would be nearly unbeatable in smooth water conditions (assuming they survive the run -- lol). Note that Richard Jenkins is essentially doing just that with his record seeking sailboat Windjet (Greenbird, if his current sponsors stay with him for a sail record attempt. His ice record attempt apparently fell through due to poor ice this last winter, but I sure wish he'd give us an update on his website.)
I'd get involved with the above described kite-board set-up if I could earn money at it (essentially replace my current job). My main interest, however, is to develop a practical sailboat that can be sailed under "any" wind condition and which can be scaled to any size. My interest in the sailing speed record with Sailien is to ideally make a craft that can break the record on one tack and then jibe and break it again on the opposite tack. Those of you that have been reading this blog for a while, know that I've been claiming I've already developed how to do this, both at the model stage (as demonstrated on my You tube video) and with my full-sized prototypes (I haven't published video or stills of the advanced prototypes). All I'm lacking is a more efficient prototype, which has been hampered by limited funds.