Running Faster than the Wind

It’s one of the great ironies of sailing. Going dead downwind, arguably the “easiest” angle of sail, is also the slowest. Thanks to the phenomenon of apparent wind, modern boats regularly sail faster than the true wind speed on a reach. But on a run, there’s no getting around the fact that the faster you go, the less pressure there is on your sails—until now.

DDWFTTW #1 from Rick Cavallaro on Vimeo.

According to Rick Cavallaro, chief scientist at Sportvision Inc.—a company founded by renowned navigator Stan Honey—the exercise began as a fun brainteaser, namely “can you build a wind powered-vehicle that goes directly downwind, faster than the wind, steady state?” The result has been a “huge raging debate across literally dozens of internet forums” and a somewhat ungainly looking vehicle affectionately named the BUFC, for “big ugly cart.” (Yes, we know that’s just three words, none of which starts with “F.” You’ll have to fill in the blanks yourself!)

In March, the BUFC, which is sponsored by Google and the airborne wind turbine company Joby Energy, made a first set of runs at the North American Land Sailing Association (NALSA) Americas’ Cup meeting on the dry lakebed in Ivanpah, Nevada. While Cavallaro and Sportvision director of manufacturing John “JB” Borton, had set an initial goal of 2X the true wind speed, the BUFC had no problems going 2.5X the wind speed, and the team now has its eyes set on 3X the wind speed.

Cavallaro says the BUFC works—even when there is a stiff apparent wind blowing in the driver’s face—because of the apparent wind being created by the spinning blades as they move at an angle to the true wind, like a sailboat sailing on a reach. The team is not revealing precise top speeds at this time, but is planning to make an official NALSA-sanctioned run in the near future.

To learn more about the project, click here.

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