639 replies to this topic

[mad]

Just agree to differ guys, we really don't need another pissing match about this. Thanks

...taking exception to a comment does not a pissing match make!

but in 5 more posts I guarantee thats where we'll be

[JMD]

I would think now would be a good time for the kiters to get their own designation as some other craft, not touching this speed, EVER!

Never say never.

Rob Douglas set the most recent kite record using a 9m off-the-shelf Cabrinha Switchblade kite. Yours, for the low price of $1,339.00 in your choice of three(3) different colors with free shipping (bar and lines cost extra): http://jupiterkitebo...ade-p-3517.html

You don't think some kind of hard or semi-hard wing kite that's optimized for 50+ instead of for usage by the general populace would change things a bit? All it takes is money.

[couchsurfer]

Just agree to differ guys, we really don't need another pissing match about this. Thanks

...taking exception to a comment does not a pissing match make!

but in 5 more posts I guarantee thats where we'll be

[mad]

Just agree to differ guys, we really don't need another pissing match about this. Thanks

...taking exception to a comment does not a pissing match make!

but in 5 more posts I guarantee thats where we'll be

Go for it that's what you want, just thought we could have one thread that didn't devolve into the standard SA shitfest.

[couchsurfer]

Just agree to differ guys, we really don't need another pissing match about this. Thanks

...taking exception to a comment does not a pissing match make!

but in 5 more posts I guarantee thats where we'll be

Go for it that's what you want, just thought we could have one thread that didn't devolve into the standard SA shitfest.

[us7070]

I would think now would be a good time for the kiters to get their own designation as some other craft, not touching this speed, EVER!

Never say never.

Rob Douglas set the most recent kite record using a 9m off-the-shelf Cabrinha Switchblade kite. Yours, for the low price of $1,339.00 in your choice of three(3) different colors with free shipping (bar and lines cost extra): http://jupiterkitebo...ade-p-3517.html

You don't think some kind of hard or semi-hard wing kite that's optimized for 50+ instead of for usage by the general populace would change things a bit? All it takes is money.

There is huge room for development in kiting gear, and I would not be surprised to see kites reclaim the record within a few years.

[Tucky]

I would think now would be a good time for the kiters to get their own designation as some other craft, not touching this speed, EVER!

Never say never.

Rob Douglas set the most recent kite record using a 9m off-the-shelf Cabrinha Switchblade kite. Yours, for the low price of $1,339.00 in your choice of three(3) different colors with free shipping (bar and lines cost extra): http://jupiterkitebo...ade-p-3517.html

You don't think some kind of hard or semi-hard wing kite that's optimized for 50+ instead of for usage by the general populace would change things a bit? All it takes is money.

One of the interesting requirements of the contest in this regard is the requirement to self start and finish with all the equipment you start with. The number that jumps out in this discussion is the efficiency of each approach, i.e. the wind strength required to set a record

[shaggybaxter]

I just did some quick comparisons to other teams, and this gives you an idea of what an achievement these guys have made.
In a sport where we crave that elusive 0.1kn, following is a quick summary of what VSR2 have done to sailing.
This is a team truly worthy all the accolades.

Following subject to ratfication (and a few bourbons)...

500m. 65.45kn. Increase of 10 kn.
B Class. Increase of 12kn.
Aus record . Increase of 9kn.
World speed record. 68.01. Increase of 10kn.
Nautical mile. Increase of 3kn.

I need to check em again, but even if it's close, well, fuck me, that simply incredible.
SB

[OZCAT]

Please, most kite boarders are just hacks who know nothing of sailing, rights of way on the water or racing. Just reach back and forth, jumping into the air to impress the uneducated. They are the wind equivalent of jet skiers.

[Cavandish]

Please, most kite boarders are just hacks who know nothing of sailing, rights of way on the water or racing. Just reach back and forth, jumping into the air to impress the uneducated. They are the wind equivalent of jet skiers.

Give that time, the sport is still young. Kite bouy racing especially, but they have some serious numbers in participation and continue to grow. To get (back) into the olympics they have just started to seriously organize, give it another few years of development and i would be both surprised and disappointed if they didn't have thier shit together.
I would think their RRS would be a bit different to account for the massive application of running rigging and virtual impossability of determining an overlap with a fast moving tiny board. I dunno, but with some thought by those that do and ....go ahead and start the flames...a restricted one design class.
I hate to say it, but racing i think would grab them a sizable number of dinghy sailors that shit looks like fun. Except the thought of some asshole charging the fleet on port tack with their kite low at 30 knots. 14' of stupid can be avoided 100+ not so much.

[tilmann]

End of quote.

So where is the purity in your run, Larso ? During your run you used more than only wind and water to go fast. By running alongside the shore as close as possible. In order to have waves as small as possible. So the proximity of the shore had a clear effect on your record.

Apart from that I like you very much :)/>
Cheers
tilmann

I don't think anyone has ever considered in 'unpure' to try to eliminate waves. (by sailing close to the shore)
the 'impurity' referred to is the huge reduction in drag which occurs when a planing surface is working at a depth of less that 50cm.

If you allow any depth, then the logical extension is to just use an iceyacht, since while moving they 'float' on a thin film of water, so that counts.... right?
In fact lets propose that, if the WSSR ever remove the depth restriction just adapt the sailrocket design to work on ice and add sensors to detect the water film level under the blades.

For kiters the ground is what the shore is for Sailrocket: It reduces wave height.

It´s true that there are several investigations which found out that flat bottoms have less drag in shallow water. But in all these investigations they "ride" the board flat. Kiters however ride their boards on the edge
A kiteboard is not a windsurfboard - kiteboarders use their board as a foil. A kiteboard is a kind of ventilated foil with extremely low aspect. Like any other foil it needs a minimum water depth to generate sufficient lift (ca. 5 cm) On 1 cm (using water only as a lubricant) you just slide around without any control. So it´s selflimiting - a rule is superfluous.

So don´t worry - after the removal of the depth rule speedkiters would stay what they are: just vessels on water driven by wind.

Well I suggest you do some investigative work on this an demonstrate that in 5cm of water a kiteboard is acting in the same way as in terms of fluids and ground interaction as in is in 50cm of water, I'm sure if you do so, the WSSRC will reconsider the rules. Some simple tank tests should be sufficient to do this, or at least challenge the current state of knowledge on this.

Personally I doubt that a kiteboard in 5cm of water is not being substantially affected by ground effects, especially of that 5cm is over a fine silt, (like burnham on sea for example). I know that boards are riden on the edge, but that still leaves a substantial wetted area of board, as the effective beam, I would be surprised if you could generate enough lateral resistance without the effective beam of the board being greater that 10cm so we would still be in the regime of the depth less that 1/2 the beam.

As noted no-one has suggested that the purity of the record is affected by waveheight, and the rules were not altered because of concerns about waveheight, the rules where set because of concerns that the physics of vessel-water interaction where very different at very shallow depths (like 5cm).

A kiteboard operating in very shallow water, where the edge of the board is very close to the bottom, will benefit from the "end plate" effect of the bottom--inhibiting the tip vortex and increasing the effective aspect ratio of the board (which is actually a foil, as I pointed out some time earlier). Because the board is very inefficient--due to ventilation and low aspect ratio--the effect of constricting the tip vortex can be expected to be significant. In fact I posit this effect is of far greater importance than the improved planing effect of shallow water.

Maybe, maybe not. Maybe a ventilated foil has not as much induced drag at the tip as a normal foil - nobody knows. Nothing is proven yet.

But this is not the question.

Given that "purity" doesn´t exist in speedsailing (look at the canal in Lüderitz !): Why should we ban hydrodynamical effects on the board caused by the ground ? (if they exist)

[couchsurfer]

Please, most kite boarders are just hacks who know nothing of sailing, rights of way on the water or racing. Just reach back and forth, jumping into the air to impress the uneducated. They are the wind equivalent of jet skiers.

Give that time, the sport is still young. Kite bouy racing especially, but they have some serious numbers in participation and continue to grow. To get (back) into the olympics they have just started to seriously organize, give it another few years of development and i would be both surprised and disappointed if they didn't have thier shit together.
I would think their RRS would be a bit different to account for the massive application of running rigging and virtual impossability of determining an overlap with a fast moving tiny board. I dunno, but with some thought by those that do and ....go ahead and start the flames...a restricted one design class.
I hate to say it, but racing i think would grab them a sizable number of dinghy sailors that shit looks like fun. Except the thought of some asshole charging the fleet on port tack with their kite low at 30 knots. 14' of stupid can be avoided 100+ not so much.

....and who says that racing around a set of cans,,,,in places that relate more to location of yachtclubs than good sailing ,,regardless of wind,,,is even a sport??!
...........I admire the purity of kiteboarding,,,not to mention the portability

[tilmann]

Pure nature - and a quite natural way of sailing. If you have ever done this you feel there is nothing wrong with shallow water ...

[tilmann]

Here another thought which just came into my mind:
If ground effect exists, would it be good for speed if you use a kite ?
Sailrocket shows us: As it has a "sail" similar to a kite which pulls upwards 30 degrees it needs a counteracting force which pulls it down.
Therefore they use that L-shaped foil which works like a hook and forces them down.
So the worst case for them (and for kiters, too) would be a ground effect which pushes them up.

[tackoften]

Tilmann,,,
mate you guy's are fast but you will never EVER get to Larso's pace,,,someone will get hurt trying and thats a given,,,Paul was peaking out,,,on the edge of spinning out,,waiting for his craft to blow up,,,at those speeds he and his team did not know what was going to happen,,,just good prep pushed him thru,,,his record will stand for a long long time,,,,

[boomer]

.I admire the purity of kiteboarding,,,not to mention the portability

Yup!

But I only see the Sailrocket as the real deal at this point....it'll do a horizon job on the kites.

[JMD]

I would think now would be a good time for the kiters to get their own designation as some other craft, not touching this speed, EVER!

Never say never.

Rob Douglas set the most recent kite record using a 9m off-the-shelf Cabrinha Switchblade kite. Yours, for the low price of $1,339.00 in your choice of three(3) different colors with free shipping (bar and lines cost extra): http://jupiterkitebo...ade-p-3517.html

You don't think some kind of hard or semi-hard wing kite that's optimized for 50+ instead of for usage by the general populace would change things a bit? All it takes is money.

One of the interesting requirements of the contest in this regard is the requirement to self start and finish with all the equipment you start with. The number that jumps out in this discussion is the efficiency of each approach, i.e. the wind strength required to set a record

Define "self start." I don't think Paul raised the wing himself, launched with a Seitech, and then cruised it over to the starting area so it looks to be pretty broad.

Agree that kites are way behind from an efficiency standpoint, which I think is where having equipment that's designed to go 60 knots instead of 20 would make a big difference, both from an outright speed and from a safety standpoint. The efficiency of VSR is much more impressive than having to wait for 45 knots of breeze to get to 55 knots of boatspeed. Elegance vs. brute force.

[Big Show]

Please, most kite boarders are just hacks who know nothing of sailing, rights of way on the water or racing. Just reach back and forth, jumping into the air to impress the uneducated. They are the wind equivalent of jet skiers.

Too funny ozcat. Wife actually had to ask me what's so funny?

But you have to admit it does look like a lot of fun and in terms of purity, I think it's as good as it gets. I'll always want to race sailboats but I MUST learn to kite.

However, the speed record is now impossible for kiting in its present configuration. As long as the power is transferred THROUGH the sailor/kiter it's simply impossible and frankly dangerous to get to Sailrocket's speeds. The limit - to me - is the physiology of the athlete.

Speedsailing has taken a quantum leap past this and I suspect Rob Douglas knows 65 is impossible until they come up with a foil and energy transfer configuration powered by a kite but NOT transferred through the kiter to the water.

Can't wait to see it. I think people forget that 65+ is #$%&ing insane fast. Geometrically faster than 55 f-a-s-t...

Let the carbon grip it and rip it. Not bone, flesh and muscle. Falling off a motorboat at Crossbow speeds is one thing. Give falling off a motorboat at 65+ a try.

People break.

[Tom Ray]

Give falling off a motorboat at 65+ a try.

People break.

True. I have wiped out at speeds above 40 knots while water skiing. It's no fun at all. I would not want to crash above 65 knots.

[edt]

However, the speed record is now impossible for kiting in its present configuration. As long as the power is transferred THROUGH the sailor/kiter it's simply impossible and frankly dangerous to get to Sailrocket's speeds. The limit - to me - is the physiology of the athlete.

Speedsailing has taken a quantum leap past this and I suspect Rob Douglas knows 65 is impossible until they come up with a foil and energy transfer configuration powered by a kite but NOT transferred through the kiter to the water.

I think our boards are fine, we have done a lot of experimenting with them but our kites are like the other guy said off the rack cabrinha switchblade. The problem with our current kites is that we have all this force pressing directly downwind. With a more efficient kite, that pulls upwind, you don't have to be nearly as strong and you can go much faster.

Kiters might just give up on it, the kite buggies after all don't try to chase the greenbird, which rocked out a 126 mph run. The greenbird looks much like the sailrocket except the wing is on the main body not the leeward pod. Kitebuggies are up to 84mph.

The problem with a 65knot record is that it's far away and tantalizingly close. I think with a bit of kite R&D we can break it.

the Sailrocket looks like she has some more speed in her with more tweaks. She'll need another huge run to put it completely out of reach like the greenbird did on land.

[couchsurfer]

Tilmann,,,
mate you guy's are fast but you will never EVER get to Larso's pace,,,someone will get hurt trying and thats a given,,,Paul was peaking out,,,on the edge of spinning out,,waiting for his craft to blow up,,,at those speeds he and his team did not know what was going to happen,,,just good prep pushed him thru,,,his record will stand for a long long time,,,,

.I admire the purity of kiteboarding,,,not to mention the portability

Yup!

But I only see the Sailrocket as the real deal at this point....it'll do a horizon job on the kites.

Please, most kite boarders are just hacks who know nothing of sailing, rights of way on the water or racing. Just reach back and forth, jumping into the air to impress the uneducated. They are the wind equivalent of jet skiers.

Too funny ozcat. Wife actually had to ask me what's so funny?

But you have to admit it does look like a lot of fun and in terms of purity, I think it's as good as it gets. I'll always want to race sailboats but I MUST learn to kite.

However, the speed record is now impossible for kiting in its present configuration. As long as the power is transferred THROUGH the sailor/kiter it's simply impossible and frankly dangerous to get to Sailrocket's speeds. The limit - to me - is the physiology of the athlete.

Speedsailing has taken a quantum leap past this and I suspect Rob Douglas knows 65 is impossible until they come up with a foil and energy transfer configuration powered by a kite but NOT transferred through the kiter to the water.

Can't wait to see it. I think people forget that 65+ is #$%&ing insane fast. Geometrically faster than 55 f-a-s-t...

Let the carbon grip it and rip it. Not bone, flesh and muscle. Falling off a motorboat at Crossbow speeds is one thing. Give falling off a motorboat at 65+ a try.

People break.

.......aww C'mon !!...you trolls are just trying to get the kiteboarders riled-up enough to try!!!

.........it's true that it'll be 'interesting' to see kites try to get the record back
,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,and I don't relish to see the failures,,,

..........but it's pretty amazing to think about the accessibility,,,portability,,,simplicity,,,purity of their equipment

[boomer]

.......aww C'mon !!...you trolls are just trying to get the kiteboarders riled-up enough to try!!!

Not at all.... it is what it is....

[couchsurfer]

I think our boards are fine, we have done a lot of experimenting with them but our kites are like the other guy said off the rack cabrinha switchblade. The problem with our current kites is that we have all this force pressing directly downwind. With a more efficient kite, that pulls upwind, you don't have to be nearly as strong and you can go much faster.

...........very good point!.....surely some tweeking could be done on kiteshape,,,
..........and probably specialized waterski with long 'edge',,,


..........but as said above,,,I sure don't want to watch the failures

[fastyacht]

However, the speed record is now impossible for kiting in its present configuration. As long as the power is transferred THROUGH the sailor/kiter it's simply impossible and frankly dangerous to get to Sailrocket's speeds. The limit - to me - is the physiology of the athlete.

Speedsailing has taken a quantum leap past this and I suspect Rob Douglas knows 65 is impossible until they come up with a foil and energy transfer configuration powered by a kite but NOT transferred through the kiter to the water.

I think our boards are fine, we have done a lot of experimenting with them but our kites are like the other guy said off the rack cabrinha switchblade. The problem with our current kites is that we have all this force pressing directly downwind. With a more efficient kite, that pulls upwind, you don't have to be nearly as strong and you can go much faster.

Kiters might just give up on it, the kite buggies after all don't try to chase the greenbird, which rocked out a 126 mph run. The greenbird looks much like the sailrocket except the wing is on the main body not the leeward pod. Kitebuggies are up to 84mph.

The problem with a 65knot record is that it's far away and tantalizingly close. I think with a bit of kite R&D we can break it.

the Sailrocket looks like she has some more speed in her with more tweaks. She'll need another huge run to put it completely out of reach like the greenbird did on land.

Kiteboards don't have a snowball's chance in hell of beating Sailrocket. Not a chance. Over 40% of the kite area is wasted--just drag-producing. The board is an inefficient low AR ventilated foil. Compare to sailrocket which has efficient aero and efficient hydro.

As I said a week or 2 back, the only way to go faster on a kite, is to essentially build a "kite" sailrocket. That means a rigid kite--not this floppy thing that rolls up in a bag. It means a harness system that goes directly to a steerable hydrofoil platform. It isn't "kiteboarding" in the "traditional" sense (as if there can be a tradition after only 10 years) but it would be a kite.

However, the stability and control is tricky. What the kiteboard gives up in efficiency (they are less efficient than an F18 cat...) it gains in control.

Furthermore, somebody is going to get killed--snapped neck or something--if the kiteboards keep trying this.

[couchsurfer]

.......aww C'mon !!...you trolls are just trying to get the kiteboarders riled-up enough to try!!!

Not at all....

.........aww,,,let's make tacking a requirement!!!

[couchsurfer]

.......aww C'mon !!...you trolls are just trying to get the kiteboarders riled-up enough to try!!!

Not at all.... it is what it is....

Kiteboards don't have a snowball's chance in hell of beating Sailrocket. Not a chance. Over 40% of the kite area is wasted--just drag-producing. The board is a inefficient low AR ventilated foil. Compare to sailrocket which has efficient aero and efficient hydro.

As I said a week or 2 back, the only way to go faster on a kite, is to essentially build a "kite" sailrocket. That means a rigid kite--not this floppy thing that rolls up in a bag. It means a harness system that goes directly to a steerable hydrofoil platform. It isn't "kiteboarding" in the "traditional" sense (as if there can be a tradition after only 10 years) but it would be a kite.

However, the stability and control is tricky. What the kiteboard gives up in efficiency (they are less efficient than an F18 cat...) it gains in control.

Furthermore, somebody is going to get killed--snapped neck or something--if the kiteboards keep trying this.

........I'd say yer guys are probably right,,,,Sailrocket probably is safe with the outright record for a good long time-and well deserved!

,,,thank gawd sailrocket,,in all it's complexity,
.........was finally able to beat the ''available on open market,,,tackable speedcraft'' record!!!

[boomer]

Furthermore, somebody is going to get killed--snapped neck or something--if the kiteboards keep trying this.

Had some spectacular crashes in shallow water at speeds of 40+ kts ....luckily only ended up with busted equipment or a bent boom in a few of those crashes.

At 60+ kts....could be a big hurt.

[edt]

It means a harness system that goes directly to a steerable hydrofoil platform. It isn't "kiteboarding" in the "traditional" sense (as if there can be a tradition after only 10 years) but it would be a kite.

From a standing position Rob can pull about 1,000 with his legs through the 500 meter course, if that force is directed towards the finish, he will be able to withstand about 3 and a half G's worth of acceleration more force than the space shuttle launching. The human is not the weak link here. The problem is that the kite at 50 knots is all drag, so we just end up plowing up a huge rooster tail and not getting any more speed. With a better kite (a wing), I think this record is in reach. But, I don't think Cabrinha is interested in building one because there's no money in it. We are stuck at something like 1.2x wind speed.

Our lite wind kites and race boards by contrast can get 2x or more wind speed in 10 knots. That's where the R&D is.

[Reht]

It means a harness system that goes directly to a steerable hydrofoil platform. It isn't "kiteboarding" in the "traditional" sense (as if there can be a tradition after only 10 years) but it would be a kite.

From a standing position Rob can pull about 1,000 with his legs through the 500 meter course, if that force is directed towards the finish, he will be able to withstand about 3 and a half G's worth of acceleration more force than the space shuttle launching. The human is not the weak link here. The problem is that the kite at 50 knots is all drag, so we just end up plowing up a huge rooster tail and not getting any more speed. With a better kite (a wing), I think this record is in reach. But, I don't think Cabrinha is interested in building one because there's no money in it. We are stuck at something like 1.2x wind speed.

Our lite wind kites and race boards by contrast can get 2x or more wind speed in 10 knots. That's where the R&D is.

If the human connected to the kite trips up and crashes (and don't tell me it won't happen, it definitely will), how much do you think will be left of them after hitting the water at 60knts? That's like hitting the water after jumping nearly 50m, like jumping off a 20 story building. After seeing that, how many people do you think would be willing to try it again?

[nroose]

So, I don't quite understand how a more efficient kite would be faster. It seems to me that the kite provides the force vector on the boarder. Does more efficient mean the direction or magnitude changes, or both?

Also, how can a kiteboard go from low aspect ratio to a more hi aspect ratio foil? Perhaps a foiling kiteboard? If the foil is a foot or so below the board, does that give them leverage and more power?

Also, the vids I have seen of kiteboard record runs, ita always looked to me like they were constantly powering on and off, with their lean going on and off. Is thre room to be leaning more consistently?

The 10 kts that SailRocket has put into the record means that something significant needs to change in how the kiters are operating to match the new record, and I think more wind is lust not enough, and evolutionary changes are probably not going to result in enough improvement fast enough to make it any time soon. And I think it's probably going to take several pretty revolutionary ideas to make up the full amount.

[fastyacht]

So, I don't quite understand how a more efficient kite would be faster. It seems to me that the kite provides the force vector on the boarder. Does more efficient mean the direction or magnitude changes, or both?

Also, how can a kiteboard go from low aspect ratio to a more hi aspect ratio foil? Perhaps a foiling kiteboard? If the foil is a foot or so below the board, does that give them leverage and more power?

Also, the vids I have seen of kiteboard record runs, ita always looked to me like they were constantly powering on and off, with their lean going on and off. Is thre room to be leaning more consistently?

The 10 kts that SailRocket has put into the record means that something significant needs to change in how the kiters are operating to match the new record, and I think more wind is lust not enough, and evolutionary changes are probably not going to result in enough improvement fast enough to make it any time soon. And I think it's probably going to take several pretty revolutionary ideas to make up the full amount.

Efficiency is faster because it means a greater multiplier of windspeed. Right now, kites need to go out in a storm to go any faster. More efficiency means going out in 35 knots. Sailrocket did it in high 20s. In other words ordinary wind.

Yes, a foiling kiteboard, But not like you might think. I should put a sketch up.

[edt]

So, I don't quite understand how a more efficient kite would be faster. It seems to me that the kite provides the force vector on the boarder. Does more efficient mean the direction or magnitude changes, or both?

Just think about how the polar diagram works for all sailing craft and you'll see why improving the kite efficiency is so important.

There is a loss of control going from a higher aspect to a lower aspect foil on kites. I think our boards are about as close to that as we want to take it.

Kiters are constantly flying their kites and adjusting their center of gravity in response to the wind just the same as the sailrocket is constantly adjusting his sail rudder, it's just that it's more easy to see on a kite.

The sailrocket has potental to get up to 80 or 90 knots. Right now I think we can catch them with mere design changes in the kites.

[DJL]

It means a harness system that goes directly to a steerable hydrofoil platform. It isn't "kiteboarding" in the "traditional" sense (as if there can be a tradition after only 10 years) but it would be a kite.

From a standing position Rob can pull about 1,000 with his legs through the 500 meter course, if that force is directed towards the finish, he will be able to withstand about 3 and a half G's worth of acceleration more force than the space shuttle launching. The human is not the weak link here. The problem is that the kite at 50 knots is all drag, so we just end up plowing up a huge rooster tail and not getting any more speed. With a better kite (a wing), I think this record is in reach. But, I don't think Cabrinha is interested in building one because there's no money in it. We are stuck at something like 1.2x wind speed.

Our lite wind kites and race boards by contrast can get 2x or more wind speed in 10 knots. That's where the R&D is.

That's like arguing that a M32 or Moth isn't fast enough to break the record, so sailboats should have been stuck too. How badly do you want to break the record? Do you think that Sailrocket was bought off-the-shelf? To advance the state-of-the-art in any discipline takes dedication, ingenuity, perseverance, funding, and any number of other qualities. Showing up at a ditch once a year and trying to go really fast with someone else's equipment is impressive, but isn't going to get it done. The entire Sailrocket team has been at this for a long time and have had to overcome some significant challenges along the way. You are right - the kite manufacturers aren't likely to spend the R&D money required to drastically improve the efficiency of their designs. That said, there are engineers and builders out there who would relish the chance to push the limits, and I'm sure they will if/when given the time and opportunity.

[Cavandish]

Considering how much folks around here look to optimize shrowds to reduce windage...kites...they certainly have some serious windage. Also, the human body is not aerodynamic at all. Any one who has riden a motorcycle on the highway knows this and those ARE the speeds we are talking about.
From what i have found in maybe a couple hours dinking around the web, the new boards being used look pretty well optimized for the application. Entirely asymetrical, shaped to not only commit to only one tack, but to my untrained eye, capture/block vortexes on the rail. Also, take advantage of ground effect. They may be able to shunt and run in the opposite direction, but i'm very suspect of such a move working with the rocker.
As far as foils, the itty bity fins look to have been curved to create negative lift opposite the force from the kite at speed. If they are obvious in a picture i can only imagine the sheer stregth it takes to make it work if a gust takes it out of balance.
All the talk of solid wings and such may be more an undertaking than they appear. While losing efficiency, a curved foil is more stable and when that instability is directly transfered to a human it would take even more skill to balance.
Not to mention additional weight aloft, provided gliders do it and a guy pedaled an aircraft acrossed the english channel. It is possible i would think, but just like sailrocket it is going to take equal parts sponsorship, craftmanship, engineering genuis and a pair of massive brass balls to pull off.
All the money in the world means nothing without the dedication and skill of those who pursue the impossible.
Having spent some time lurking on various kite forums, seriouly considering taking up snow kiting, i have found it rather strange reading threads about how traditional sailing is all about throwing money around to achieve new technology from the America's Cup to Hydrophere and sailrocket. Perhaps i am just being naive, but when i see a new craft breaking the mold i see the architects, engineers and builders first well before the sponsors who pay their bills. As far as the sailors who get to operate them, well for them i have a great deal of envy tainted respect.
Hopefully the more of the kiters will come to find out that we have a HELL of alot more in common than they often acknowledge. Also discovered they now have a kite specific RRS ... are they prepaired for a dinghy/beachcat racer invasion? I am a middle aged weekend hack, ie the largest group in sailing, given the choice of a Laser or a couple kites, a raceboard and people to race. That is a tough choice. To build an olympic team, that is damn solid ground, because while hacks such as i aren't winning shit the generation behind us will grow up with the sport. Big pools are greater than small, sailing is sailing on a board, a dinghy or a lead dragging team effort.

[OZCAT]

Lol. My other past time is fishing, but I don't own a rod.

I have done a bit of kiting but my passion is mainly windsurfing and sail boat racing. Did not really enjoy the kite (hacks) crowd. I know there are some serious kite sailors / racers out there, but they are few and far between.

As for coming off a board at 70 knots, racing water skiers have been coming off at in exces off 100 knots for a couple of decades.

[boomer]

As for coming off a board at 70 knots, racing water skiers have been coming off at in exces off 100 knots for a couple of decades.

Try doing that in 18" of water or less and come do an abrupt stop when the bottom comes up doing 40+ on a windsurfer, which results in a head and shoulder plant....and let me know how it feels...from experience at 40+ plus knots, I haven't had any serious injuries in such shallow waters, but didn't always walk away without a good bruise or two...I've also been hooked in and hit bottom and gone over the handlebars, for a head and shoulder plant a couple times...even with my helmet on it rung my bell and a good neck wrench....much more then 50 hooked in and over on a windsurfer, could have been a big hurt.

Kiteboarders don't usually get the head plants that a windsurfer occasionally experiences in shallow water on a speed run....but kiteboarders can and have been seriously hurt, when things got beyond their control. Fortunately most kiteboarders, just like most windsurfers who know how to sail overpowered, usually do quite well overpowered, or at least better then the average person who's not accomplished at overpowered conditions....I consider myself quite accomplished at overpowered conditions and maintaining control....but when things go to schitt, bad thing can and do happen....and it can be a crap shoot.

[OZCAT]

At those speeds, depth is not so much the issue as it is like skimming across cement. Yes, it does hurt but you survive.

[dogwatch]

racing (kites) i think would grab them a sizable number of dinghy sailors that shit looks like fun.

Given that around here kiting is banned most places dinghies operate, I kind of doubt it.

[fastyacht]

racing (kites) i think would grab them a sizable number of dinghy sailors that shit looks like fun.

Given that around here kiting is banned most places dinghies operate, I kind of doubt it.

Banned? Wow. That hasn't happened here. Not even sure how it could happen here. Then again we don't have any dinghies anyway.

[dogwatch]

^

Where's "here" for you?

A lot of British dinghy sailing is on inland waters. Most ban kites.

A major British dinghy sailing area is Chichester Harbour. There's half a dozen clubs, including HISC which runs many international regattas. Harbour bye-laws ban kitesurfing. That means HISC can't host kitesurfing from the club (although it could use nearby beaches which are popular for kites).

I'm told kitesurfing is banned in Sydney Harbour.

etc.

[Big Show]

It means a harness system that goes directly to a steerable hydrofoil platform. It isn't "kiteboarding" in the "traditional" sense (as if there can be a tradition after only 10 years) but it would be a kite.

From a standing position Rob can pull about 1,000 with his legs through the 500 meter course, if that force is directed towards the finish, he will be able to withstand about 3 and a half G's worth of acceleration more force than the space shuttle launching. The human is not the weak link here...

Clearly the human IS the weak link here if he's required to squat/transfer 1000lbs of force and pull 3.5 Gs over 500 meters. What's that going to look like at 65+ knots?

Because that's what we're talking about here. 65-70 knots... Insane.

I'll say it again, it is IMPOSSIBLE for kiting to get to those speeds in present configuration. You'd need to train someone of Olympic Weightlifting strength to be even better than Rob Douglas. Not going to happen - and I'd wager the top kiters know it full well.

Now something utilizing a kite directly transferring the power to some sort of foiling craft. My bet is if we see kites try for 65-70, this will be how it's done. Can't wait to see it tried seriously by a team with that singleminded focus Sailrocket's team has shown.

[fastyacht]

Lol. My other past time is fishing, but I don't own a rod.

I have done a bit of kiting but my passion is mainly windsurfing and sail boat racing. Did not really enjoy the kite (hacks) crowd. I know there are some serious kite sailors / racers out there, but they are few and far between.

As for coming off a board at 70 knots, racing water skiers have been coming off at in exces off 100 knots for a couple of decades.

I just looked that up. Crazy! One girl skier ate it at like 100 MPH and she's back up and racing in a few minutes. And it looks like they have the rope around their waists! How's that work? Do they have some sort of "breakaway" link?

Looking at the kite crashes at the ditch, it gets really ugly, the way the kite keeps dragging the guy.

[boomer]

At those speeds, depth is not so much the issue as it is like skimming across cement. Yes, it does hurt but you survive.

Sometimes you do skim, but usually if it's that much of an out of control launch, it's more of a rag doll crash or getting flung. When your windsurfing on the edge of control or get that way overpowered gust, the board wants to lift, sheet out and your gonna lift more, so it's actually better to sheet in and stall the sail. If it's a totally overpowering gust and and it's almost impossible to sheet in to stall the sail, if you have time you unhook and step off the back of the board. If you have enough strength hold on to the boom as you step off,because quite often if you stepped off on the weather side, you can waterstart in deeper water, and be merrily on your way again. Stepping off in shallow water you don't have this option, so quite often it's best to let go of your rig, as you go into a recline and hope for a slide. Doesn't always work out this way though, especially if your still hooked in, because your either gonna get flung, rag dolled or over the handlebars planted, and when lucky if you can get unhooked skim. If your board goes up, or your fin cavitates and the board goes sideways, your basically fucked unless you can turn your board downwind and reattach the flow to the fin, and stop the cavitation. Sometimes you can lay your sail down on the leeward side, but this usually results in going off the front of the board and swimming back to the rig in deep water, in shallow water do this and could end in a rag doll.

Crashes start at 2:29 in the first vid.

https://www.youtube....h?v=H3qffZALcnI

https://www.youtube....h?v=HIJ1jZQcSSY

Mostly just pure speed on this one as you get as close to the edge of the ditch as possible.

https://www.youtube....h?v=z727NSVQ1nA

[dogwatch]

^
Thanks for those. So are the boards going right up to the bank for the flattest water or is there another reason?

[boomer]

Precisely....the flattest water for the most speed. The key with speed in windsurfing, is maintaining just enough board contact with the water with the aft end of the board,maintain just a slight nose up attitude of the board, without having the nose bounce up and down to much, load the fin with your rear foot and heel with pressure, use the front foot as an accelerator pedal by pressing down, and maintain control of the sail and board with little movement to so fin doesn't ventilate.

Sometimes the rear foot will cramp up because your pressuring up so much,especially after a bunch of speed runs, but you deal with the pain of the cramp and keep going, sometimes the front foot will cramp, but usually it's the rear foot only cramping, best to rest well between speed runs to eliminate cramping, but when it's nuking you get back up the line and take your run when your number is called, trying to make as many runs as possible.

[Big Show]

Great videos Boomer. Also great description of the control required and how it can go wrong. Seeing Bjorn Dunkerbeck ventilate and face plant is something else. Chilled guy - he said something like 'it's no fun if it's not dangerous.'

These windsurfers and kiters are amazing athletes. I just think the concept of sheeting in and holding onto that power 1:1 isn't going to get any of them close to Sailrocket. They need too much wind and, well... People break. And Sailrocket is simply too efficient.

On her three record breaking runs Sailrocket's wing WAS flying and that foil did so much bloody work. A thing of beauty. Hope we someday get to see pics of the foil mod.

[boomer]

The speed and the thrill to me, is indeed what makes it fun.

In the future I think the kiters and the windsurfers will eventually go for records in their own class. Pretty much in essence what the windsurfers are doing now.


The Sailrocket is in a league of it's own, and I'm very happy for what they've been able to accomplish as team.

Everything they've been through, it's nice to see it paying off in spades.


I'm also looking forward to what the Hydroptere will continue to achieve over distances.

It's all good in my book...and I wish the best for everyone.

[edt]

Clearly the human IS the weak link here if he's required to squat/transfer 1000lbs of force and pull 3.5 Gs over 500 meters. What's that going to look like at 65+ knots?

rite now the speed kiters are pulling 50-100 pounds and accelerating at less than half a G. We aren't even close to human limits. The kites however are like giant sky anchors. Kite lines snap at between 600 and 800 pounds and you shouldn't put more than 300 pounds on them.

[Tom Ray]

It's all good in my book...and I wish the best for everyone.

+1 to that. And I do mean everyone.

[nroose]

So, I don't quite understand how a more efficient kite would be faster. It seems to me that the kite provides the force vector on the boarder. Does more efficient mean the direction or magnitude changes, or both?

Also, how can a kiteboard go from low aspect ratio to a more hi aspect ratio foil? Perhaps a foiling kiteboard? If the foil is a foot or so below the board, does that give them leverage and more power?

Also, the vids I have seen of kiteboard record runs, ita always looked to me like they were constantly powering on and off, with their lean going on and off. Is thre room to be leaning more consistently?

The 10 kts that SailRocket has put into the record means that something significant needs to change in how the kiters are operating to match the new record, and I think more wind is lust not enough, and evolutionary changes are probably not going to result in enough improvement fast enough to make it any time soon. And I think it's probably going to take several pretty revolutionary ideas to make up the full amount.

Efficiency is faster because it means a greater multiplier of windspeed. Right now, kites need to go out in a storm to go any faster. More efficiency means going out in 35 knots. Sailrocket did it in high 20s. In other words ordinary wind.

Yes, a foiling kiteboard, But not like you might think. I should put a sketch up.

So a more efficient kite just gives you more power for the same wind? And then it's up to the board and person to handle it?

[edt]

So a more efficient kite just gives you more power for the same wind? And then it's up to the board and person to handle it?

It's all related to the polar of your sailing craft, draft and lift. You might have noticed as you sail faster and faster the angle of apparent wind moves upwind into your direction of travel. A more efficient sail lets you sail closer to the wind and go faster. Right now kiters are bound by the inefficient kites at 1.2x wind speed. Now of course you can build a stronger boat and just make the sail bigger, and force the kiter to pull harder, but what good does it to go build everything bigger for incremental improvements, when you can almost double the efficiency with a better kite.

[Reht]

My biggest worry would not be the initial impact when the kiter goes for a crash, unless they're able to release themselves completely from the kite it'll just keep dragging. All these kites have safety systems that depower them pretty quick, thing is that at 50knts of wind there's a hell of a lot of drag on anything, even a depowered kite. That drag will keep dragging the kiter until they release or the kite shreds itself, after the first impact they keep bouncing, these trenches aren't so wide and suddenly you're not bouncing on water at 50knts you're bouncing on earth at 30. That's gotta hurt...

[dogwatch]

pull 3.5 Gs over 500 meters.

A bit of maths will show that 3.5G acceleration over 500 metres from a standing start has you travelling around 360 knots at the end. I think we are a little way away from that.

[couchsurfer]

My biggest worry would not be the initial impact when the kiter goes for a crash, unless they're able to release themselves completely from the kite it'll just keep dragging. All these kites have safety systems that depower them pretty quick, thing is that at 50knts of wind there's a hell of a lot of drag on anything, even a depowered kite. That drag will keep dragging the kiter until they release or the kite shreds itself, after the first impact they keep bouncing, these trenches aren't so wide and suddenly you're not bouncing on water at 50knts you're bouncing on earth at 30. That's gotta hurt...

.............that's why they smoke da big spliffs mon!!

 bigjoint.jpg   14.99K   5 downloads  bigjoint.jpg   14.99K   5 downloads

[OZCAT]

Ski racers have 2 handles. Once they pull themself up and settle, they pull them behind their back and grib with 1 hand whilst the second hand grabs the line in front. FYI 125 mph crashes are not gracefull, often face plants and cartwheels but you still skim. Perhaps you need to go faster boomer.

This crash is over 100 mph.
http://m.youtube.com...h?v=FN2IZvQjTPA

[Big Show]

pull 3.5 Gs over 500 meters.

A bit of maths will show that 3.5G acceleration over 500 metres from a standing start has you travelling around 360 knots at the end. I think we are a little way away from that.

Not my #s. From EDT's earlier post. And it's not the G's really - it's the dynamic, not static, loading/squatting required imho.

Regardless, looking at Rob Douglas' former WR run, there's a great deal of strength being used to harness the power of the kite and transfer the power to the edge of the board. Not surprisingly RD is built like an NFL linebacker (or a flanker for that matter).

I don't buy that kites can get to 65+ in this configuration. I would hazard a guess that those select few that have been over 50 on a kite would agree.

Spaceballs said it all: Ludicrous Speed.

[Tom Ray]

Spaceballs said it all: Ludicrous Speed.

They need plaid kites.

[hoom]

So anyway, WSSRC has been working their way through the records.

59.23 kts Outright 500m record from 16th Nov
http://www.sailspeed...d-27/11/12.html

59.37kts Outright 500m & 55.32kts 1nm record from 18th Nov
http://www.sailspeed....-02/12/12.html

So its now properly officially fastest

Next one should be the big mother of god 65kts record, I guess a couple more days for them to crunch that one.

[boomer]

Ski racers have 2 handles. Once they pull themself up and settle, they pull them behind their back and grib with 1 hand whilst the second hand grabs the line in front. FYI 125 mph crashes are not gracefull, often face plants and cartwheels but you still skim. Perhaps you need to go faster boomer.

I haven't done a speed trial for a long time. Most of my speed sailing is for my own pleasure at Kline Spit about a 45 minute drive from my house. Mostly just kiters up there anymore. The NWWSA hasn't run a windsurf speed trial there for years. We also used to have speed runs down in the Gorge at the Klickitat River bar, but the sand bar got washed out in '96. The sandbar is reforming, but it's only about a 100 meters which isn't long enough for a ratified event.

Maybe next year I'll go to Luderitz and have a go at it and try and set a record for the fastest old man on the course. Anders and Bjorn are looking pretty old these days, I'd probably fit right in.

The 50+ kt. speeds being obtained now are in winds of almost 45 kts. You'll only see incremental increases in Antoine Albeau windsurf record of 52.05, and it's gonna take over 45 kt. winds to do it. .The wind speed was 43 knots on his record run. In winds maxing at 45 kts. that day his streak was 5 runs over 50 knots and 6 runs over 51 knots. Anders Bringdal followed not far behind with a best of 51.45 which is also a new World Record on Production boards.

https://www.youtube....e=results_video

https://www.youtube....Ssqfgfo&list=UL

[High Flow]

no helmet?

[Fasterdamnit]

Nautical mile record is official!

http://www.sailspeed....-02/12/12.html

[Fasterdamnit]

Nautical mile record is official!

http://www.sailspeedrecords.com/wssr-newsletter-no-218.-vestas-sailrocket.-outright-and-nm.-02/12/12.html

AND the new 65 knot outright!!!!

Killer!

http://www.sailspeedrecords.com/wssr-newsletter-no-219.-vestas-sailrocket-2-outright-sailing-speed-record-04/12/12.html

[JohnMB]

pull 3.5 Gs over 500 meters.

A bit of maths will show that 3.5G acceleration over 500 metres from a standing start has you travelling around 360 knots at the end. I think we are a little way away from that.

and a little common sense will remind you that G can be acceleration or force per unit mass.
at which point 'pulling 3.5G' can mean holding 3.5x your body weight on the harness system....

ask yourself which is a more reasonable interpretation.

[fastyacht]

pull 3.5 Gs over 500 meters.

A bit of maths will show that 3.5G acceleration over 500 metres from a standing start has you travelling around 360 knots at the end. I think we are a little way away from that.

and a little common sense will remind you that G can be acceleration or force per unit mass.
at which point 'pulling 3.5G' can mean holding 3.5x your body weight on the harness system....

ask yourself which is a more reasonable interpretation.

Huh?

Let's just for a moment assume (incorrectly in this case) that 1 of those 3.5 g is supporting the mass. The other 2.5 are accelerating it. (standing on the ground you are accelerated at 1 g).

After 500 meters with that kind of acceleration, you are still going too fast. It just doesn't happen. Rather, there is rapid acceleration for a moment, followed by a high steady-state load. Force due to acceleration versus force due to resistance. The standing still thing of course confuses people because we live in an accelerated reference frame!

[tamaozy]

pull 3.5 Gs over 500 meters.

A bit of maths will show that 3.5G acceleration over 500 metres from a standing start has you travelling around 360 knots at the end. I think we are a little way away from that.

and a little common sense will remind you that G can be acceleration or force per unit mass.
at which point 'pulling 3.5G' can mean holding 3.5x your body weight on the harness system....

ask yourself which is a more reasonable interpretation.

Huh?

Let's just for a moment assume (incorrectly in this case) that 1 of those 3.5 g is supporting the mass. The other 2.5 are accelerating it. (standing on the ground you are accelerated at 1 g).

After 500 meters with that kind of acceleration, you are still going too fast. It just doesn't happen. Rather, there is rapid acceleration for a moment, followed by a high steady-state load. Force due to acceleration versus force due to resistance. The standing still thing of course confuses people because we live in an accelerated reference frame!

ANYWAY, all too confusing for my little brain. How bought that Sailrocket, it rocks. Wicked fast and now it is official. Yippee.

[hoom]

Fasterdamnit got the link in first but here is the text of official record:

The WSSR Council announces the the establishment of a new World Record.
Record: Outright World and World “B” Division Sailing Speed Record
Venue: Walvis Bay. Namibia.
Name: Paul Larsen. AUS.
Equipment: Vestas SailRocket 2. Inclined rig Hydrofoil Proa.
Date: 24th November 2012. @ 13.32 hrs
Course length: 500 metres
Current: Nil
Elapsed time: 14.85 secs
Speed: 65.45 kts

Comments: Previous Outright and “B” Division Record: 2012. Vestas SailRocket 2. Paul Larsen AUS. Walvis Bay NAM. 59.37 kts

John Reed
Secretary to the WSSR Council

65.45kts

[nroose]

So a more efficient kite just gives you more power for the same wind? And then it's up to the board and person to handle it?

It's all related to the polar of your sailing craft, draft and lift. You might have noticed as you sail faster and faster the angle of apparent wind moves upwind into your direction of travel. A more efficient sail lets you sail closer to the wind and go faster. Right now kiters are bound by the inefficient kites at 1.2x wind speed. Now of course you can build a stronger boat and just make the sail bigger, and force the kiter to pull harder, but what good does it to go build everything bigger for incremental improvements, when you can almost double the efficiency with a better kite.

To me it seems like a kite is a bit different, because the kite and person/board are relatively independently steered and move relatively independently. Can you try to adress my question? How does it affect the force vector that the kite is producing relative to true wind?

And how are kites going to change the basic physics to produce significantly more speed?

[Guitar]

Gentlemen,
A little respect for the thread please.

Take it to Speed Kiting.

Live Long and Prosper

SailRocket

[shanghaisailor]

First thing is the WSSC ratification needs to be on the front page - SCOT ARE YOU UP AND AWAKE?

This news is as big as Chuck Yaeger going through the sound barrier, seriously the solving of the ventilation on the foil enabled larso to go through an equivalent barrier where control surfaces became ineffective - if i read it right, i am not a phsycist or naval architect.

As far as the dreamers who think kites will take this back any time soon I see 3 problems (maybe I am being too simplistic)

1. A kite doesn't float with the crew on board, couple this to the talk about fancy kites - which presumably be fragile and complex shapes and materials - the need to be able to start, from rest, unassited leads me to think problem one would be to get the whole thing out of the water and to on top of the water.

2. I have driven a speedboat at 60kts sitting in a nice padded seat, (30ft Phantom with 400hp on the back) yet when you hit a bump it feels like your spine is coming up through your head. If the kites remain in the current configuration with the human body as part of the drive chain there will be real issues with even small waves especially on real water rather than artificial cqanals.

3. You need to find someone with either the balls or stupidity to risk a 65kt unprotected impact with water should a run go wrong. At that speed it would be like hitting concrete. I have impacted at a mere fraction of that (about 25-30kts) and it knocks the shit out of you.

So if you can find a kite boarder who has the skill, the physical strength and the VERY low regard for the potential dangers along with the kiting ability to control a complex aerodynamic kite at those sorts of speed and know enough to give the required developmental input to the design team along the way you could have a new record breaker - but not this year!

In the meantime, let's not take anything away from Paul, Helena, Malcolm and all the team - this is so much more than just a speed increase, it is a genuine breakthrough.

See ya on the water, but at much lower speeds than these guys

SS

[Varan]

First thing is the WSSC ratification needs to be on the front page - SCOT ARE YOU UP AND AWAKE?

This news is as big as Chuck Yaeger going through the sound barrier, seriously the solving of the ventilation on the foil enabled larso to go through an equivalent barrier where control surfaces became ineffective - if i read it right, i am not a phsycist or naval architect.

... snip snip...

You can read about it at http://www.sail-world.com The mythical front page is exactly that if you have an original iPad (never again). Crashes Safari ever time.

[nroose]

First thing is the WSSC ratification needs to be on the front page - SCOT ARE YOU UP AND AWAKE?

This news is as big as Chuck Yaeger going through the sound barrier, seriously the solving of the ventilation on the foil enabled larso to go through an equivalent barrier where control surfaces became ineffective - if i read it right, i am not a phsycist or naval architect.

... snip snip...

You can read about it at http://www.sail-world.com The mythical front page is exactly that if you have an original iPad (never again). Crashes Safari ever time.

Yeah. The front page is notoriously invalid. I've offered my services to no avail.

[dogwatch]

and a little common sense will remind you that G can be acceleration or force per unit mass.

It wasn't taught that way in my physics class and:

"The term g-force is technically incorrect as it is a measure of acceleration, not force." http://en.wikipedia....g/wiki/G-force"

[JMD]

First thing is the WSSC ratification needs to be on the front page - SCOT ARE YOU UP AND AWAKE?

This news is as big as Chuck Yaeger going through the sound barrier, seriously the solving of the ventilation on the foil enabled larso to go through an equivalent barrier where control surfaces became ineffective - if i read it right, i am not a phsycist or naval architect.

As far as the dreamers who think kites will take this back any time soon I see 3 problems (maybe I am being too simplistic)

1. A kite doesn't float with the crew on board, couple this to the talk about fancy kites - which presumably be fragile and complex shapes and materials - the need to be able to start, from rest, unassited leads me to think problem one would be to get the whole thing out of the water and to on top of the water.

2. I have driven a speedboat at 60kts sitting in a nice padded seat, (30ft Phantom with 400hp on the back) yet when you hit a bump it feels like your spine is coming up through your head. If the kites remain in the current configuration with the human body as part of the drive chain there will be real issues with even small waves especially on real water rather than artificial cqanals.

3. You need to find someone with either the balls or stupidity to risk a 65kt unprotected impact with water should a run go wrong. At that speed it would be like hitting concrete. I have impacted at a mere fraction of that (about 25-30kts) and it knocks the shit out of you.

So if you can find a kite boarder who has the skill, the physical strength and the VERY low regard for the potential dangers along with the kiting ability to control a complex aerodynamic kite at those sorts of speed and know enough to give the required developmental input to the design team along the way you could have a new record breaker - but not this year!

In the meantime, let's not take anything away from Paul, Helena, Malcolm and all the team - this is so much more than just a speed increase, it is a genuine breakthrough.

See ya on the water, but at much lower speeds than these guys

SS

I see a number of people pointing out why the "kites are dead forever" crowing is a bit misplaced given the equipment currently being used but I haven't seen anybody taking anything away from the achievements of the SailRocket team.

Why would the kite itself need to be able to be started from the water? Cite the specific rule from the WSSRC: http://www.sailspeed...rules-2010.html It would be like requiring SailRocket to pass a capsize test. "Just stand on the foil and bounce a little bit, Paul, she'll come right up."

[JohnMB]

and a little common sense will remind you that G can be acceleration or force per unit mass.

It wasn't taught that way in my physics class and:

"The term g-force is technically incorrect as it is a measure of acceleration, not force." http://en.wikipedia....g/wiki/G-force"

the CONSTANT g
can express two functionally equivalent ideas
either the acceleration of a free body close to the surface of the earth or
the body force per unit mass on a mass close to the surface of the earth

now i would disagree with your wiki article about whether i is technically correct or not to use the term g-force but since you where the first to use the term here that is pretty irrelevent
even your article starts with the sentence

g-force (with g from gravitational) is a term for noticable and measurable acceleration. It is not a force, per se, but a force per unit mass.

in engineering (and physics) g is used ion many many ways
I very much doubt your physics teacher insisted that this constant could only be used when a body was accelerating, And I have little doubt that he knew that there was no sensible difference between a body force/unit mass of g and an acceleration of g below relativistic speeds.

[mad]

[Big Show]

Fasterdamnit got the link in first but here is the text of official record:

The WSSR Council announces the the establishment of a new World Record.
Record: Outright World and World “B” Division Sailing Speed Record
Venue: Walvis Bay. Namibia.
Name: Paul Larsen. AUS.
Equipment: Vestas SailRocket 2. Inclined rig Hydrofoil Proa.
Date: 24th November 2012. @ 13.32 hrs
Course length: 500 metres
Current: Nil
Elapsed time: 14.85 secs
Speed: 65.45 kts

Comments: Previous Outright and “B” Division Record: 2012. Vestas SailRocket 2. Paul Larsen AUS. Walvis Bay NAM. 59.37 kts

John Reed
Secretary to the WSSR Council

65.45kts

Amazing. Simply amazing.

Roughly a 10% jump from their recent 8% jump.

Hope to see pics of the foil mods that made it happen but understand it's closed doors right now while - hopefully - the team figures out how to monetize 10+ years of work.

[edt]

Can you try to adress my question? How does it affect the force vector that the kite is producing relative to true wind? And how are kites going to change the basic physics to produce significantly more speed?

modern kites have tons of drag that's why they can't get more efficient vectors, they fall backwards into the wind window a typical leading edge is 6 inches to a foot in diameter

[us7070]

The boards seem to have tons of drag too..

i'm not sure why they aren't using boards more like raceboards for speed attempts - boards with good fins.

[edt]

The boards seem to have tons of drag too..

i'm not sure why they aren't using boards more like raceboards for speed attempts - boards with good fins.

The entire board is a ventilating fin, the actual fin on a speed board is there only for stabilization. While a formula kite racing board will start out flat and then foil up off the fins a speed board uses the edge of the board to foil. I'm convinced the boards are very well designed. The best kind of R&D has gone into them, the trial and error at high speed kind.

There has been zero R&D for kite design at high speed. I'm not sure kiters actually need to get to 65 knots. So dangerous, I would hate to lose someone over this.

[Steve Clark]

Can you try to adress my question? How does it affect the force vector that the kite is producing relative to true wind? And how are kites going to change the basic physics to produce significantly more speed?

modern kites have tons of drag that's why they can't get more efficient vectors, they fall backwards into the wind window a typical leading edge is 6 inches to a foot in diameter

You need to improve the L/D ratio of the kite.
That may be easier said than done.
The wing on Sailrocket acts an awful lot like a very efficient kite on a very short and very rigid string.
SHC

[JohnMB]

Can you try to adress my question? How does it affect the force vector that the kite is producing relative to true wind? And how are kites going to change the basic physics to produce significantly more speed?

modern kites have tons of drag that's why they can't get more efficient vectors, they fall backwards into the wind window a typical leading edge is 6 inches to a foot in diameter

You need to improve the L/D ratio of the kite.
That may be easier said than done.
The wing on Sailrocket acts an awful lot like a very efficient kite on a very short and very rigid string.
SHC

interesing

I was just making the same point when this reply arrived

the difference between sailrocket and a kite board is principally that the airfoil is attached rigidly to the board and the foil is supported by a stable platform

at optimum efficiency both are hydro airfoils (thanks for the references to that Larso, very cool reading )
to get the best out of each you need to optimize the airfoil (rigid sail or kite) optimize the hydrofoil (foil or board acting as a foil) and control the connection between the two

The nice thing about the sailrocket is it is sufficiently stable to allow detailed experimentation, precise changes in the angle and shape of the wing, or the foil and their relative orientation
for kites there is the benefit of being able to get into higher windspeeds aloft, but eventually the same issues will hit, indeed any attempt at over 60kts will required boards to address the issues of ventilation at the back edge of the foil, and the associated losses that sailrocket found when they hit their 50kt wall.

[edt]

You need to improve the L/D ratio of the kite.
That may be easier said than done.
The wing on Sailrocket acts an awful lot like a very efficient kite on a very short and very rigid string.
SHC

Actually it is very very easy to improve the L/D ratio of kites. Right now kites run an L/D ratio of somewhere around 3 or 4 to 1 tho of course L/D is not just a number but a function of wind speed.

Personally I like to ride Fuels, which has an even worse L/D ratio. The advantage of low L/D's in wakestyle is that when you load to pop out of the water, the kite has further to travel to the edge of the window giving you better pop and better slack for your handle pass. Also when the kite stays deeper in the wind window it is much less likely to hindenberg and fall out of the sky. Now it's true a better L/D ratio helps you go upwind better and gives you a better top speed, but it doesn't really matter, you go upwind so you can do a trick downwind it doesn't matter, what you want is good handling. Kites with high L/D also are really awful doing megaloops, they don't give you a big yank downwind.

Anyway, there are a bunch of other reasons, but even with racing kites like the cab kites that tend to win all the races, the L/D ratio at 65 knots is not that important because when we go kite racing, it's always about 10 knots. When the wind picks up to 20 knots, racing is called off for that day and we switch to freestyle.

There is simply a tremendous amount of improvement that could be done to the kites. Will it be done? Do we really want to go 65 knots in a kite? I dunno. Our boards are not where the improvement needs to be it's in the kites. We could easily get up to 10 or 15 to 1 L/D ratio's but you couldn't use that kite for freestyling, only for racing, and it wouldn't help normal racing, only high speed racing.

[Raked aft \\]

You need to improve the L/D ratio of the kite.
That may be easier said than done.
The wing on Sailrocket acts an awful lot like a very efficient kite on a very short and very rigid string.
SHC

Actually it is very very easy to improve the L/D ratio of kites. Right now kites run an L/D ratio of somewhere around 3 or 4 to 1 tho of course L/D is not just a number but a function of wind speed.

Personally I like to ride Fuels, which has an even worse L/D ratio. The advantage of low L/D's in wakestyle is that when you load to pop out of the water, the kite has further to travel to the edge of the window giving you better pop and better slack for your handle pass. Also when the kite stays deeper in the wind window it is much less likely to hindenberg and fall out of the sky. Now it's true a better L/D ratio helps you go upwind better and gives you a better top speed, but it doesn't really matter, you go upwind so you can do a trick downwind it doesn't matter, what you want is good handling. Kites with high L/D also are really awful doing megaloops, they don't give you a big yank downwind.

Anyway, there are a bunch of other reasons, but even with racing kites like the cab kites that tend to win all the races, the L/D ratio at 65 knots is not that important because when we go kite racing, it's always about 10 knots. When the wind picks up to 20 knots, racing is called off for that day and we switch to freestyle.

There is simply a tremendous amount of improvement that could be done to the kites. Will it be done? Do we really want to go 65 knots in a kite? I dunno. Our boards are not where the improvement needs to be it's in the kites. We could easily get up to 10 or 15 to 1 L/D ratio's but you couldn't use that kite for freestyling, only for racing, and it wouldn't help normal racing, only high speed racing.

I agree w/ Edt, Kite efficiency is the answer to stay in the hunt, and it's only going to happen with private/sponsored r&d. The industry doesn't have interest in anything non-marketable, which is what this would be.

I'm envisioning a rigid wing in a delta shape with two panels (front & back) to create a somewhat trimable wing as your speed increases.
Where the rider would launch and accelerate with max camber, then flatten the wing out for top speed.

The bitch would be controlling the beast from the launch point, as it would be extremely unstable from the get go, and any type of grouding of the wing would spell destruction.

on the board side, i envision going more toward a waterski type arangement, either slalom or double, but designed for speed. The speed racing waterskiers are reaching speeds in excess of 100 mph, so that technology is there. (albeit being pulled by a fossil burner)
A more efficient kite like i described, would pull more upwind, so as you burn downwind in the course you wouldn't need near as much side resistence, it would look much more like a boat pulling a skier.

[fastyacht]

A more efficient kite like i described, would pull more upwind, so as you burn downwind in the course you wouldn't need near as much side resistence, it would look much more like a boat pulling a skier.

I'm afraid that part is a logical fallacy. Look at how hard sailrocket's main foil is working.
Remember, going *upwind* in the apparent wind. That means 90% or more of the force is sideforce.
The boards are just as much a problem here as the kite, in my opinion.

[JimC]

To change topic a bit, been keeping a vague eye on the Luderitz Speed Challenge website, and am distinctly amused by much talk about records yet apparently trying to ignore the 65.45 knot elephant in the room...

[edt]

To change topic a bit, been keeping a vague eye on the Luderitz Speed Challenge website, and am distinctly amused by much talk about records yet apparently trying to ignore the 65.45 knot elephant in the room...

That's because the best kiters in the world are in france rite now waiting for the mistral rob douglas alex caizergues etc. Luderitz is more about looking at some nice national records. Rob just did a 53 in an easy practice run at salins du midi, in less than ideal wind. don't expect to hear about this from the ludertiz site they are competitors for the best speed kiting location.

"As regards the outright World Speed Sailing record, recently set by Sailrocket, that’ll take time but we’ll get there." -- morgan douglas rob's little bro

[Munter]

Kites have the added difficulty of needing to fly their sail into the right part of the window to generate the optimum lift drag. This isn't impossible and is done by kite flyers all the time, but a low drag kite is going to need some pretty good controlling to be able to develop 60kts +

[tilmann]

It´s very simple: All we need are thinner tubes (at least half the diameter than now) and less belly in the sail.

First advantage: the the kite would have less drag.

Second advantage: the kite can eat the gusts better - you don´t have to power on...power off...power on...power off all the time.
Similar to a modern windsurfsail you would have to move it at the start, but once you have reached a certain speed it would generate constant pull. Even in gusts. No depower needed anymore. Power-on all the time. Means more speed.

Third advantage: You can use better boards if you have better kites. Current speedboards are built in the way they are because they must equalize the unconstant pull of the kite ! With constant pull you can use stiffer boards with more grip and longer and stiffer fins, because the gusts don´t pull you over anymore. Means more speed.
(Reminds me of the development in windsurfing 30 years ago.)

Fourth advantage: If no depower is needed, it means less "work" at the bar for the average rider, too. So kiting becomes way easier - you just have to lean back and let the board go !
So it´s interesting for the whole kite industry.

Technically we just need more air pressure in the tubes to reduce diameter. So the tubes must be enforced - we need a completely new tube technology !

[yowie]

Some recognition for Sailrocket in Australian media.
This is Warwick Hadfield giving a brief report this morning on Radio National.
It can be found after the cricket, golf and hockey, and before the rugby and AFL.

[hump101]

Back in 1999 I built and flew a solid wing kite as part of the development of my speedsail design. It was small (2.4m x 0.8m) and we flew it several times in 10-12kts of wind. It was brutal. Zero force at take off (I had to run upwind) then with the very low drag it would accelerate across the window so rapidly it was impossible to control (I had a three line setup, but it traversed the window in around 1 second on 40m lines, and I couldn't react fast enough). The force generated at these speeds was so great that I was snatched back down the sand for 20m or so, really viciously.

The inertia of the kite at this speed, and the low drag, meant that it didn't stop at the top of the window, but continued flying to windward 10-15m or so until it had sufficient negative angle of attack that it would plunge back to earth until the lines went slack, then it would flutter back towards me. This gave me a couple of seconds to scrabble back to windward, and the kite then either hit the ground, or if it drifted downwind enough, the lines would become tight and the nightmare would repeat itself until my shoulders or hands gave up.

I also have modern power kites, and this little solid wing kite of less than 2 sqm was far more powerful than my 20sqm Naish because the flight speed was so high.

The construction was a hollow foam core with composite skin, so we cut large portions of the skin away and replaced it with film. The theory was to try and reduce the inertia so the the over-flying would be reduced, permitting some kind of control, but of course the initial acceleration was even greater and the available time to react on the control line was nowhere near enough for me.

We eventually removed so much structure that the wing tips broke on landing. With broken tips the drag increased to such a point that the kite could be controlled, but couldn't make power because it was now slow. After enough crashes it would no longer fly.

We moved to a rigid wing on a long beam, as Steve says, a kite on a rigid stick, as a means of controlling the wing, as we couldn't see a way of controlling the wing in free flight in a manner that would satisfy the WSSRC. I have thought a lot about that solid kite since then, and I think, with an electronic closed loop control system operating on a second flap, it could be managed. The power available is just staggering, as it is not constrained to boat speed, and the low drag means that the power can be generated at angles that are useful for speed sailing, even when the kite is yawing around.

Attached Files

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•  wingcrsh.jpg   26.86K   27 downloads

[nroose]

Can you try to adress my question? How does it affect the force vector that the kite is producing relative to true wind? And how are kites going to change the basic physics to produce significantly more speed?

modern kites have tons of drag that's why they can't get more efficient vectors, they fall backwards into the wind window a typical leading edge is 6 inches to a foot in diameter

Can you try to adress my question? How does it affect the force vector that the kite is producing relative to true wind? And how are kites going to change the basic physics to produce significantly more speed?

modern kites have tons of drag that's why they can't get more efficient vectors, they fall backwards into the wind window a typical leading edge is 6 inches to a foot in diameter

I guess I'm not convinced. If the angle of the lines are like that, then as you are moving, you are effectively letting the kite go up relative to its lift. I am pretty sure to get any real power, the lines need to be relatively close to perpendicular to the direction of travel.

[Tom Ray]

Back in 1999 I built and flew a solid wing kite as part of the development of my speedsail design. It was small (2.4m x 0.8m) and we flew it several times in 10-12kts of wind. It was brutal. Zero force at take off (I had to run upwind) then with the very low drag it would accelerate across the window so rapidly it was impossible to control (I had a three line setup, but it traversed the window in around 1 second on 40m lines, and I couldn't react fast enough). The force generated at these speeds was so great that I was snatched back down the sand for 20m or so, really viciously.

Not sure I'm understanding this right. In 10-12 knots of wind, that little kite dragged you 20 meters?

[edt]

I guess I'm not convinced. If the angle of the lines are like that, then as you are moving, you are effectively letting the kite go up relative to its lift. I am pretty sure to get any real power, the lines need to be relatively close to perpendicular to the direction of travel.

that's not the angle of the kite lines it's the angle of the pull from the kite which is also dependent on angle of attack. This particular diagram is when the rider is going 50 knots, so for current kites there is almost no extra speed it can take. For the more advanced kite you can see that you can add another 20 or 30 knots before apparant wind shifts so that the kite pull is perpendicular to the direction of travel. The diagram is just a snapshot at a particular speed

[hump101]

Back in 1999 I built and flew a solid wing kite as part of the development of my speedsail design. It was small (2.4m x 0.8m) and we flew it several times in 10-12kts of wind. It was brutal. Zero force at take off (I had to run upwind) then with the very low drag it would accelerate across the window so rapidly it was impossible to control (I had a three line setup, but it traversed the window in around 1 second on 40m lines, and I couldn't react fast enough). The force generated at these speeds was so great that I was snatched back down the sand for 20m or so, really viciously.

Not sure I'm understanding this right. In 10-12 knots of wind, that little kite dragged you 20 meters?

Forget anything you know about inflatable traction kites. Powerful as they may be, compared to a solid wing, they are docile and slow, and they don't make power at the high angles of the flight window. That little solid wing could accelerate to 75kts in 12 kts of wind (9 deg AoA), and the momentary force generated was around 2.5kN peak (my calc, not measured). Because the force is generated so high in the flight window, it is not possible to dig your feet in, it just lifts you up and throws you downwind.

I was using a cruciform control bar, which in retrospect was a mistake, because as the wing shoots up it applies more and more angle of attack, which doesn't stall the wing as it was going faster and faster, until I was pulled off the ground and rotated by the control line, but the wing still continued climbing and arcing to windward until the AoA is lost and drag, plus me hitting the ground to leeward, prevent it going any further.

The photo is with the wing flying on very short lines (5m or so) in an attempt to limit speed and hence add some control, but it was like holding on to a bucking bronco and no better controlled, though less dangerous as the forces were lower. In the photo the wing is fluttering back to leeward having already overshot me, and looks like it is about to crash with so much roll. It was very hard to get pictures of it soaring, as the soaring portion happened so fast. Somewhere in the old tapes there may be some video.

[Steve Clark]

If you follow it ll the way down the rat hole, you end up with Sailrocket.
The kite s made larger and more efficient an brought closer to home so it can be more accurately controlled and more tightly linked to the payload.
It might be possible to build a less massive Sailrocket, which might lead to some efficiency, but frankly it seems that the waves ( or lack of them) becomes a bigger and bigger problem the smaller you get. So there is some merit in going the other way ( a la Hydrotere) and building a large vessel that can operate in more normal conditions.
Like these guys : http://project.kiteboat.com/
SHC

[moody frog]

http://project.kiteboat.com/

As an early leading Kite designer Don Montague knows one thing or two about kites.

Interestingly he has now moved to tethered-wings carrying wind turbines. Going fast in loops and not in a straight line, but certainly teaching them a lot about rigid-wings behaviour..

http://www.makanipower.com/

[edt]

i cant wait until kite designers make changes. There hasn't been any change in kite design since the Legaignoux brothers invented the kite bridle in 2004 or so. Kite manufacturers have needed a kick in the nuggets for a while now to get them out of their comfort zone. I know I said, why would kite manufacturers build this, but I realized they have needed this sort of challenge for a long time, they just never knew it.

Thanks sailrocket. We needed that.

[JohnMB]

http://project.kiteboat.com/

As an early leading Kite designer Don Montague knows one thing or two about kites.

Interestingly he has now moved to tethered-wings carrying wind turbines. Going fast in loops and not in a straight line, but certainly teaching them a lot about rigid-wings behaviour..

http://www.makanipower.com/

this is the way I was thinking would be the most interesting step forward
if you can get the kite flying a stable loop around the center of the window you eliminate the overflying instability issue, and can create a very fast very powerful kite.

its sole purpose would be to go downwind fast, forget any reasonable control or use, but it has potential to do something interesting if the physics can be worked out properly.

It may be that such a system is self limiting and can only generate reasonable power at a static platform, but it's definitely worth looking into.

[moody frog]

I do not think any of the kite manufacturers, supposing they are ready and/or able to spend the money, have access to the forward thinking designer required.

[mad]

You never know, seems this might become a record to chase! Its caused a lot of interest, its been covered by a quite a few engineering news sites/blogs.
There must be a smart aero guy and or sponser to take it on.