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Kiwi led world speed record


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...knot that I should be encouraging a Kiwi record....

but foilers seem to be the logical next step. Reducing the water drag.....sails are gone...solid wing sections.

 

I need to find out more, but I have been told that there is a 26 foot tri that is a foiler. It (i have been told) will do 26 knots in 10 knots...

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Hmmm, Foils are hardly a next step. They have been around for as many years as solid wings for sails or maybe even longer. The trick now is to get daimensions down to a fine edge of balance between making it powerful enough and yet maintain the least friction. And that is for both Sail and Foil. That is why they can go from Speed machine to Train wreck in an instance.

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forget the sailing - I'll go with the Green Command pod of girls !

 

Well, there are my ideas anyway. I think I need to find somebody who is some sort of a design specialist, who understands the forces involved - and Really understands how to determine C of E for etc, for sort of craft, and can 'model' it using software.

 

Can anybody recommend such a person pse ??

 

Meanwhile, take a look at these pics .. and tell me this sort of stuff isnt exciting :D

post-11548-141887189815_thumb.jpg

post-11548-14188718983.jpg

post-11548-141887189833.jpg

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To model C of E, you first have to have data to input. Sure you can have a good educated guess if you are an experienced enough designer. But it will never be accurate enough to make the fine detailed calculations playing with the toys in the Pictures. So you need to build a model and then test and then scale up. That's why they spend so much time in wind tunnels. Then once you have the data, you can start changing things on a computer model and see the differences. The more data you can input, the greater the accuracy in the output.

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Right .. Agreed - that a mix of skills is required - and they dont have to (or rather, is unlikely to) reside in one person. So far then, for Design phase we need:

 

- Aeronautical / marine engineering design skills

- Software modelling skills - for something like 'Solidworks' ..

 

What other skills are required, in a team to design a potential, world beating craft ??

 

Assumptions (for now): Wish to:

1) Use proven configuration (e.g Longshot), as basis for design

2) Use 2 x Windsurfer sails (like Longshot) because of cost factors

3) Use foils - like http://carafinohydrofoilboard.com/development

4) Consider use of modern 'glider pod', as basis for crafts aerodynamic pilot pod, craft controls, and craft attachment points for craft outriggers (rather than wings).

 

OK Can anybody recommend such a person / persons, or design consultancy, which might have the right 'smarts', skills, and pragmatic mindset ??

 

Cheers DHRB

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2) Use 2 x Windsurfer sails (like Longshot) because of cost factors

Wellllllll, there's a problem right there. Two problems actualy. The words "cost factor" is problem no.1. You can't have a limit to "cost factor" when designing these kind of things. No2 is you can't start the entire design with limiting the most essential part of the design right from the get go. Think of it this way, the Dream Liner didn't get designed because someone said, we have this wing sitting out the back of the workshop that should do, it's worked OK on the 747 aircraft we biult, so lets start with that and work backwards. You just end up with a slightly different version of the 747. You have to start with want you want to achieve. That would be "speed". Then what on. That would be Water or Sand. One requires wheels and the other requires a Hull. Both have different ways of providing the Friction, so you have to engineer then means of least frisction with greatest speed. And that is where all the designs come unglued. At some point, the design will reach a speed where the speed equals the coefficient of Friction and the craft wants top change from a ground based design to an air based design. Lots of other design issues and restraints fill the gaps between that and the end result which is the wing to power it all. So in reality, unless you can do a lot of it yourself, you need to have boatloads of cash and the means of digging up even more boatloads when needed. So often the guys behind such projects are very good at finding thiose Boatloads. Hence a great deal of time Grant Dalton spends is in finding money for Team NZ.

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Point taken .. Thanks man .. forces us to think critically ..

 

Cost is a contributing reason. However, the main reason for planning on using windsurfer sails is based on the observation that the (outright) record has swung back and forth between Massive craft / budget (i.e. Yellow Pages and Hydroptere) - and windsurfers. The point being that a well designed, highly efficient simple craft can match a huge budget, big craft. So I have chosen to go the 'simple and efficient' route ..

 

The other reason is back to this principle of developing an already good / proven idea. This makes sense to me. Longshot still has the 'Class A record' which it set in 1992. And of course it used old fashioned windsurfer sails. I reckon the Longshot type configuration is a good one - so reckon it makes sense to use it - and make it better ..

 

See, I am putting it out there on the forum, cos I want to be instrumental in generating some excitement round this - and gathering a team of like-minded people, with the right skills and abilities to actually 'do something' .. so there you are: wearing my heart on my sleeve ..

 

So folks: do you have any professional skills / expertise which you would be (potentially) willing to bring to the table ? You can always email me. dhrbernard@gmail.com or ring me on 027 6660904

 

Cheers DHRB

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The problem with a windsurfer Sail is, think about how a windsurfer works. The surfer is connecting the driving Force from the sail to the board. He is holding the sail at the Mid point ruffly, so the cut is such that the sails power is developed at around that balance point. If to much energy was developed high up, the Surfer would be pulled over. Too far back, and the Surfer would struggle to pull the sail toward him. Too low down and the board would be pushed sideways too much. The design suits the purpose. A Windsurfing sail would prbably not work well on a Sailing Dingy for instance. So for the speed machine, you have to design the sail as part of the package. Where do you want the CoE and so on. It is all quite complex. I understand enough of the process to understand that I don't know enough about being a good yacht designer.

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I think though the suggestion is solid foil sails but using the configuration of Longshot which happened to use windsurfer sails. So a bi-plane rigged foil/sail (aka AC45's for want of a better phrase) on foils. Clearly the concept will work and just replacing the old windsurfer sails with foils should result in an improved performance.

 

I've got no skills to offer you other than encouragement and best wishes. Trifoilers are awesome and I love the concept!

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hey thanks guys. I hear the message re the windsurfer / CE / design factor .. And, I know enough to know that I dont know enough about this area either .. actually its half the reason I am looking to identify some smarts With this sort of knowledge .. So, point well taken chap - and your response reinforces that .. Thats cool.

 

Re the AC45 mention. Once again - Thanks! The main point I take, is that there already is HUGE knowledge out there for extreme craft .. OK, I shall contact the AC team directly, and see whether there is some resource who could potentially be available ..

 

I am also concerned about cavitation effect on foils - so I shall contact Fastacraft / Wotrocket

 

As you say; magine a twin rigged Longshot / AC45 type craft .. Geezz !!

Hey thanks chaps. Need your enthusiasm .. Cheers DHRB

post-11548-141887189944.jpg

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what about a trifoiler with a couple of these new type of cavitating foils being used by vestas sailrocket, the sails replaced with wing masts/sails as seen on the ac 45, of course shaped to handle the speed range you want to achieve.... and longshot is the forerunner of the trifoiler,it was designed and built by the Ketterman brothers in california.

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The lowest drag and lightest fuselage

Yes and no. Lowest Drag...well drag comes from Friction in soime way. Friction is what allows the thing to remain controllable. No friction at all and you would be off with the wind and no faster than that wind. Lightest....well that is also part and parcel. If you get too liught, then you are no going to "hold" onto the water and create a resistance to the effort created by the wind and thus once again, get blown across the sea by the wind with no movement in the direction you want.

So looking at it another way, the resistance (which includes weight) is also what allows you to use a "wing" to give you speed and direction. For a yacht in water, even the Hull/keel and Rudder are a wing. It is also the "vane" that allows the sail to be trimmed to a certain direction.

For a land yacht, the Hull is not neccesarily a wing, But it acts as a Vane to control the direction of the sail.

If you look at the scenario like this.

 

.................................(0).............................................

-10 -9 -8 -7 -6 -5 -4 -3 -2 -1.... +1 +2 +3 +4 +5 +6 +7 +8 +9 +10

Lets say (0) is the ultimate speed to wind that can physicaly be achieved by the laws of physics that Only God knows the final number for. Man is trying to achieve it.

(O) is purposely placed above the other numbers, because it floats along either - or + lines slightly. The negative numbers are all the factors like Friction, weight, wrong design etc that naturally slow the craft down. The positive numbers are the points at which control is lost and the craft losses the Friction that keeps it coupled to planet Earth. For a short time before that point of lost control, zero may move in either direction breifly. But because it is not a controlled and repeatable speed, it is will aways want to come back to it's centre point of whatever that actual theoretical maximum possible speed is. Or ion other words, the carft may reach it without knowing in a very brief moment as the craft is out of control and crahsing.....maybe.

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Simple AA. Those oh so many times you know you have no control, then you are approaching that "zero" point.

 

Broaches are only a meer starting point. Waves are only 1 to 2 meters for most.

 

Now a broach off a 10 meter wave is far more exciting and has more intimate feelings and knowledge of losing control.

 

Yes there are rogue waves so much bigger. Off South Africa there is an area where they occur more frequently. There was a map somewhere showing that a few years ago.

 

So imagine a broach off a 20 meter wave. You will be a lot closer to the "ZERO" now, and the speed of free falling increases with height and the oh so much more loss of control.

 

No good crying for mummy then :lol:

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OK I get it, but then we must be talking about a different set of criteria for "0" if we're talking outright speed in waves of around 2 cm. The crying to mummy thing would still apply though.

 

I'd be keen to be the test pilot for this project but I aint a boatbuilder, or mathematical theoritician, or nuclear physicist, or aeronautics engineer or whatever is needed.

 

Actually I just love trifoilers!

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Know what you mean - I have been fascinated with them for years too, hence ..

I mean - check out how much faster than a Hobie catamaran this one is going. Awesome - and note that there are no white caps !!

 

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I didn't realise the zero hadn't lined up. Man did that take some doing. It looks fine before I submit and then is all different once I view it.

Anyway, Zero is the "sweet spot" of maximum controlled speed possible, Which everyone is trying to achieve. Negative numbers are slow return of speed, but safe. Positive numbers are out of control and letting go or already has and you have a train wreck on your hands.

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Know what you mean - I have been fascinated with them for years too, hence ..

I mean - check out how much faster than a Hobie catamaran this one is going. Awesome - and note that there are no white caps !!

 

http://crew.org.nz/forum/viewtopic.php?f=47&t=17842

Think you have Youtube hyperlink issues as your link is to a crew forum! Can you have another go?

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