To bad only max speed and not over 500m, but they will get there.

news here but only in french
http://www.hydroptere.com/

We've all seen a pelican gliding right at wave top height. Anyway to get that effect on a sailboat?

Yeah using molecular gravity effect displacing daggerboards. Your boat will no longer float ON the water but instead on TOP of the water.

A sail-powered ekranoplan?

http://en.wikipedia.org/wiki/Ground_effect_vehicle

Cool!

Unfortunately they seem to have been beaten to the magical first to break 50knots - official record over 500m - by the kitesurfers.
"Yesterday the Lüderitz Speed Challenge saw Sebastien Cattelan of France become the first human being to sail at more than 50 knots (93kph) – a world record he held for only 24 hours before compatriot Alexandre Caizergues snatched it away with not one but three runs over 50 knots – reaching a top speed of 50.57 knots (93.65kph)."
These speeds are verified, but are still subject to ratification by the WSSRC.
source : www.luderitz-speed.com

From Friday`s news : Coming into today’s event, he (Cattelan)was struggling with an unrelated small injury, requiring him to reduce his activity. “I’ve been in bed the last three days, concentrating on what I would do today. Then I just did it,” he says. According to Cattelan,
his record breaking run of today saw a maximum speed of 58 knots – 107kph – on the GPS, with an average of 54.5 knots over 200m.

Again, I would be more impressed by hydroptre than kite boards accoplishing this feat over the 500m mark. I do believe that the principles are different and am not sure that super-cavitaion applies to the boards in the same way it does boats.

I am surprised they aren't wearing helmets... they should be.

The principles of cavitation are universal for all vessels. When the pressure of the water reduces enough it will boil at the ambient temperature.

Designing to avoid or control the cavitation at those speeds is the important part.

Supercavitation is generally a term used when trying to induce cavitation in special circumstances, propellers and torpedoes and the main areas it is used.

http://en.wikipedia.org/wiki/Cavitation

ehh, that would have to be rephrased too :

... Yesterday the Lüderitz Speed Challenge saw Sebastien Cattelan of France become the first human being to sail at more than 50 knots (93kph) USING A WATERBORN CRAFT. ...

Even a nitwit like myself have been doing 500 mtr runs at or just over 50 knots using 20 year landyachts and a track only 10 mtr upwind from these Kite Dudes (the dry part of the beach right next to the 20 cm deep water they are using). My class 3 landyacht friends/collegea's are doing around 65 knots on the same track with homebuild rotating mast cars and 7.5 sq. mtr sail area. And lets not forget about the kings of sail speeds the iceyachters who laught at those speeds.

Wouter