Two kiters have had peak speed of over 60knots and several at over 58knots:
http://www.gps-kitesurfing.com/default. ... peedType=9

So it is possible, however, the right conditions to sustain this for 500m are hard to find.
Yes more efficiency is required.
Kite speed sailors are by far the most efficient on a knot per $ ranking though:) which to me is way more impressive than a knot per wind strength ratio

For ultimate speed and efficiency records I think speed kiter's should change how they ride.

Let's think parachuting for a moment (at normal altitudes )
- Gravity is big force and strong acceleration
- Air resistance (friction) limits terminal velocity to about 200km/h when flat
- With diving you can achieve faster speeds, up-to 320km/h
- source: http://en.wikipedia.org/wiki/Parachuting

Now back to kiting. Kite pull is vectored so only small portitition of kite line pull is transferred to forward speed of the kiter and normal kite force is less than gravity. Kiter standing up has big factor to air resistance. Then there is water resistance to beat.

What I am thinking is to use something like "air chair" (hydrofoil chair) with aerodynamic hull. I remember seeing a youtube video disabled man kiting with special chair. IMO kite speed buggies "prove" the point.

I have seen this video quoted before as being of the run where Seb hit 61.25 knots for 2 seconds in October 2009.

It shows that the channel is open to the sea.

I had a quick tot up of the price of windsurf speed gear.

NP 5.4m EvoV sail £850
Carbon Boom £650
100% carbon 4m mast £525
Mistral speed board about £1200
Mast base and ext. about £100
Fin about £150

Total about £3500

Kitesurf
Genetrix 7m Hydra with bar 1150 Euro (£930)
Only production speedboard I could find was the 2010 Underground at $700 without straps. (£440) Most top guys use customs so probably more expensive. At a guess £700?
Pads straps and fins about £150

Total about £1750?

So roughly half the price of windsurf speed.

Meh, I have got to 42 knots on a stock twintip and 9m Fuel.

[quote="Tone]

Meh, I have got to 42 knots on a stock twintip and 9m Fuel.

[/quote]

That's going some on that gear.

Tilmann - hitting 54 knots on a bit of plywood.

I consider myself, told.

Anything over 30 knots is impressive to me.

While we were talking about costs, I just thought it worth mentioning that Tilmann can shape a bit of wood and for 25euro and the cost of a standard wave kite, he can do 54 knots.
In speed, you cant beat kiteboarding in bang for the buck.

Sorry, thats not true. He did NOT use his canal when he did 61 kn. As you can see here:

Thanks for correcting that Tilmann.

I had seen that video titled with 115 kph in the past, but this video from October 2009 and this article show they were running on open water - which makes the speed seem even more impressive.

http://translate.google.co.uk/translate ... CHYQ7gEwBw