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 Post subject: Re: Back to the drawing board- how will we beat Sail Rocket?
PostPosted: Fri Nov 30, 2012 4:31 pm 
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Location: Denmark
Race boards can not go really fast, because of two things:

1. The big and multiple fins and size are useless and way too much drag compared to small single fins as on speed boards.

2. Control is almost impossible with such a fin size on such wide boards :o


So a raceboard is not a speed board, but an "upwind" board, that still has reasonably good speed on deep reaches and halfwind because of a flat rockerline - but still restricted hugely compared to "faster" boards, because of the fin size and lack of control.

:D Peter


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 Post subject: Re: Back to the drawing board- how will we beat Sail Rocket?
PostPosted: Fri Nov 30, 2012 6:40 pm 
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Location: The Naki
golf ball bottoms to the boards?
aerodynamic latex gimp suits.
skelton board that you lie down on?

I think the key is finding a perfect location with clean howling wind and perfect water conditions.


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 Post subject: Re: Back to the drawing board- how will we beat Sail Rocket?
PostPosted: Fri Nov 30, 2012 7:53 pm 
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Location: Ford Lake, Michigan
plummet wrote:
golf ball bottoms to the boards?
aerodynamic latex gimp suits.
skelton board that you lie down on?

I think the key is finding a perfect location with clean howling wind and perfect water conditions.


sailrocket is doing 2x wind speed, kiters are doing 1.2x wind speed and the faster we go, the lower our multiplier.

To get to 70 knots with our current gear, kites are going to be doing 1x wind speed. We can probably get to 60 knots at 1.1x wind speed, so we can break 60 knots at 55 knot wind speed with our current gear.

I dont know about you but I dont really consider it sailing when all you do is hold onto a kite, and go directly downwind in a hurricane. It's like saying the high dive record belongs to people that failed to suicide after jumping off the golden gate bridge.

We need to get up to 1.7x wind speed, at 45 knots then we can do 77 knots (89mph). There's no question we need a more efficient kite to do this. The cabrinha switchblade has too much drag to get more than 1.2x at 50-60 knots.


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 Post subject: Re: Back to the drawing board- how will we beat Sail Rocket?
PostPosted: Fri Nov 30, 2012 8:20 pm 
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Location: The Naki
got to reduce line/bridle drag. carbon nano lines?

shorter lines.

I agree a solid carbon bat wing kite. it will slice you in half if it hits you but dang it will go fast.

maybe a squirell suit so the person can generate there own power.

train up midgets to fly kites? less surface area?

purpose build 1" deep lake for perfect wind angle.

hover board? design a board that will just float about the surface of the water once at speed.... no resistance.....


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 Post subject: Re: Back to the drawing board- how will we beat Sail Rocket?
PostPosted: Fri Nov 30, 2012 8:30 pm 
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Location: south east pa PKF SUX!!!
Looking to the land speed record again

They did 84 MPH in 15-30 gusting to 55.
If we take 55 that would be 1.52 X wind speed
If we take 40 that would be 2.1X wind speed
30 would be 2.8 X wind speed

I would say there are already kites that are efficient and fast, So they might not be water relaunchable but we only care about the speed right. That sailrocket can obviously only go in one direction but it goes fast. Sure kite designs can be tweaked to get more speed but why not get the most of whats out there.

Sailrocket spent tons of money on that thing. Wouldnt it take the wind out of their sails if a kiteboarder with a few thousand in gear beat their record.

I think more "outside of the box" thinking about board design can get that extra speed. Everything thats fast on the water has very little actually IN the water. How about some sort of tunnel hull that almost flys at speed. Only thing that needs to be in the water is the fin to counteract the downwind pull.


Last edited by snobdr on Fri Nov 30, 2012 8:31 pm, edited 1 time in total.

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 Post subject: Re: Back to the drawing board- how will we beat Sail Rocket?
PostPosted: Fri Nov 30, 2012 8:31 pm 
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plummet wrote:
purpose build 1" deep lake for perfect wind angle.hover board? design a board that will just float about the surface of the water once at speed.... no resistance.....


i no ur joking but according to the rules you cant hover and the depth has to be at least 50cm otherwise wont be ratified


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 Post subject: Re: Back to the drawing board- how will we beat Sail Rocket?
PostPosted: Fri Nov 30, 2012 8:39 pm 
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I'm not sure about the wind speed to board speed ratios mentioned above. In winds up to around 25 knots it is possible "from experience" to almost double the wind speed. That starts to reduce with more wind thus proving it is a drag problem. I believe it's more a problem of kite drag than board. It is also apparent that heavier riders do better in stronger winds so again it's the downwind drag/pull in stronger winds that may be the problem. Lighter riders like myself at about 11.5 stone do better in moderate winds for wind to speed efficience on smaller kites, the smaler kite will always be faster than the bigger kite that the heavier rider needs so do you really need to be overpowered? I think not but on a square course it's a different story to when the wind is at a better angle to allow release of the board edge, when on a good angle the power soon dissapears as soon as you start to release edge and go further down wind. I think kicking some ideas around are really good for progression but there are probably only a dozen riders in the world with the experience to put some new ideas to the test and feed back. Rob has a top team around him so unless someone has a Eurika moment I would be taking a lot of notice of what them guys are up to. On the subject of foils, I'm not convinced they are better than single skin kites for speed on water, they may be good on land in stable wind but take the average 35 knot UK gusty wind......... No thanks.


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 Post subject: Re: Back to the drawing board- how will we beat Sail Rocket?
PostPosted: Fri Nov 30, 2012 9:13 pm 
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Location: south east pa PKF SUX!!!
http://peterlynn.com/world-kitebuggy-sp ... rd-broken/

just going from their numbers.


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 Post subject: Re: Back to the drawing board- how will we beat Sail Rocket?
PostPosted: Fri Nov 30, 2012 9:15 pm 
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Location: Ford Lake, Michigan
snobdr wrote:
Looking to the land speed record again. They did 84 MPH in 15-30 gusting to 55.


yeah the land speed record is a good example of just how inefficient kites are. You cant really compare land kites to water kites. Even the best sailboat on water only gets 2x up to 70 or so knots on water. But on land, the record is held by this thing called the Greenbird, which looks exactly like like a proa like the sailrocket but for land and they put the sail on the main tube instead of the leeward pod. It got 126 mph in 30, at more than 4x wind speed. A mere 2x wind speed on land means kites have way too much drag. Should be at least 3x on land, and somewhere between 1.5x to 2.0x on water.

84mph is so far behind the 126mph record . . . . We need more efficient kites. Wings that you unfold and build like a hangglider, not ones you pump up.


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 Post subject: Re: Back to the drawing board- how will we beat Sail Rocket?
PostPosted: Fri Nov 30, 2012 9:19 pm 
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Joined: Sun Oct 21, 2007 7:24 pm
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Location: Utah ish
Kiterocket...Sail rocket with a kite and not a sail.


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