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High-Tech Hydrofoil
An anonymous submitter sent in links to a super-sophisticated hydrofoil/catamaran which intends to break various water speed records for wind-powered vessels. Max speed: 45 knots. A couple of fansites have more photos of the craft in action.
Yellow Pages Endeavour is a planing vehicle which is VERY different to a hydroplane based craft. One skims the water and the other lifts as much as possible entirely out of it. Wetted surface area on both is TINY, and so both are theoretically fast, but the hydroplane has got to be able to handle at least some waves whereas YPE would no doubt disintegrate. YPE ran for (and got) the speed record in a depth of <1m of water after all. So under real conditions Hydropetre is more promising - especially for the 24hr distance record which it looks like they're going for.
Big cats and tris are WILD, so one that's largely out of the water(!) is definitely the regime of those French nutter who are brave enough to push these things hard (and Grant Dalton of course :)
The cats in The Race were routinely at 35 knots so I don't think 45 is out of the question for a radical craft. This has been under development for a long time after all.
Hey, didn't many of the Formula40 cats and tris have some sort of hydroplane appendages? They were way cool... Are there pics of them anywhere? I only have one Becken calendar... :-/
You can't cross the atlantic in 5 days on a calm sea. You need wind and lots of it. I talked to a swedish guy (can't remember the name) who was in a crew that attempted the atlantic record a few years back. They waited weeks for the right weather conditions : a typhoon ! Gog
This was built just down the road from my office.
It is the second version - the first one broke during testing.
It is on beautifull piece of carbon fiber under sail. As long as it doesn't hit anything hard in the water (whale, container, tree trunk...) it will hold the new transatlantic record.
It is not meant to beat the outright speed sailing record, but it possibly could under the right conditions.
realkiwi
The beauty of the canted main foils is that they automatically counter heeling. As the boat heels, the lee foil is immersed further and consequently generate more lift; meantime the weather foil is immersed less deeply, and generates less lift. Additionally, leeway causes the lee foil to have an increased angle of attack and the weather foil a decreased, or even negative, angle (although lift from the lee foil acts counter to leeway, and it's possible to tune a hydrofoil to sail with very little leeway at all).
For totally neutral heeling the resultant vectors of the lateral foils should cross at exactly the centre of effort of the rig; if the resultant vectors cross above the centre of effort, you'll get negative heeling!
So, sorry, your Linux box isn't needed - not for that anyway!
I'm old enough to remember when discussions on Slashdot were well informed.
Even ocean going sailing hydrofoils aren't new, and they are a lot harder to design than 'round the bouys' boats. Dave Keiper's Williwaw did a number of offshore passages in the 1960s - my memory is he did San Francisco - Hawaii, but I can't find any confirmation of this just now.
For me the problem with the Hydroptere design is rear steering. The risk is that with the centre of effort of the rig being high, the stern of the boat will be lifted out of the water leading to a forwards capsize - this is why, for example, ice yachts and land yachts no longer rear steer. Still, lovely boat.
I'm old enough to remember when discussions on Slashdot were well informed.
looks to me like a single rudder on the middle hull, which is normal for a trimaran. what looks like small rudders on the foils are more likely analogous to the fin on a surfboard, which is used for directional stability. another option would have been 2 rudders (analogous to most catamarans), 1 on each outer hull. only the rudder on the leaward(?) side (away from the wind, lijzijde in dutch) hits the water and is used for steering. That said.. I've done some sailing and it's quite possible to completely loose control at high speed. this is NOT a fun thing. as someone mentioned though.. a forward flip would be worse(I know.. I've done a forward flip once, although not in any of this hightech stuff. An Optimist at 10+ beaufort will do just nicely) don't plow your bow into a wave at 40 knots!
No one can understand the truth until he drinks of coffee's frothy goodness.
--Sheikh Abd-Al-Kadir, 1587
when this trimaran (three hulls, trimaran. two hulls, catamaran) hits a whale at about 40 knots, I do not only see a big repair bill. probably the lifting planes will instantly disintegrate, and there's this sliced and diced whale in its wake. big mess. hit whale, whole boat drops down about about a meter, which may not be such a smart idea at 40 knots downwind with the gennaker up. still pretty cool thing though, but I would have used rigid sails for a real speeddemon. btw.. anyone found a pic with the 240 m^2 gennaker?
//rdj
No one can understand the truth until he drinks of coffee's frothy goodness.
--Sheikh Abd-Al-Kadir, 1587
hmm... cool, you can actually attend regular races with a hydrofoiling moth.
for the non-sailers: the Moth is an international class which is VERY loose in its design. overall length of the single hull(on waterline), mastlength, surface area of the single sail, and effective mastlength are most of the requirements.
It will probably become a strict class though, which has happened before with Moth designs. the olympic Europe class was originally a Moth design, which turned out so good that that particular design won most races. This design is now the Europe.
//rdj
No one can understand the truth until he drinks of coffee's frothy goodness.
--Sheikh Abd-Al-Kadir, 1587
it scares the crap out of me. This thing just looks unstable. They are talking about doing a trans-Atlantic race. All I have to say is the crew of that thing has some cajones. Sure is beautiful though.
If a fully submerged object can break mach 1 due to cavitation (sp?) why couldn't a hydrofoil blade do so as well?
tcd004
Piceze
According to www.speedsailing.com the current record for 10 sq metre sail craft over a 500 metre course, is 45.34 knots - in 1993. As the site's name suggests, there is more infomation on most aspects of speedsailing - including hydrofoil design - at the above address.
Mod up (+1 Iwant1)
134340: I am not a number. I am a free planet!
No really... there is a hydrofoil type sail boat that looks very similar to the one shown out for a while now. It's a Trimaran. The official product page is here: http://www.windride.com/wrrave.shtml (I think that's the official one) These things get out of the water at about 18 knots I beleive. I've seen them at one of the local marinas where my friend has his sailboat. The go much faster than a sail boat and that's before the rise above the water.
--- tracer.ca
Hydrofoils are nothing new but I have to say, this thing looks pretty slick. I'd love to take it out for a spin.
/. It's not something I'd have associated with the /. crowd. Perhaps I need to reconsider the site demographics...
I have to question though, why is is being posted on
About the hydrfoil... it's a nice evolutionary step, building on an established technology. Not quite as inspiring at the earlier article on the newest entrant in the cement canoe race.
--
--Got Lists? | Top 95 Star Wars Line
Check out some of those picture, you can really pop a wheelie (well, a rudder) with those things!
But you touch on why I don't think they'll break the Trans Atlantic Record, any kind of chop is just murder on this kind of boat. Although if they plan on doing the crossing in less than five days, they'll sit and watch the forecasts until they figure they'll have five days of relatively calm seas and go for it then. Not just any five days will do!
This hydrofoil looks incredibly awesome, I wish I could take a trip in it. It's not quite such new technology however. Hydrofoils have been around forever, this is just a more perfectioned version of it all.
here is one that you can actually afford. this thing rocks !! take a look - i am salivating now
I was going to mention Yellow Pages Endeavour - the truely exotic Australian "Speed pod" as they call it. (That particular "boat" is almost impossible to define as anything but an "it") Of course, Yellow Pages can only sail on one tack, which makes it rather limited.
I also seem to recall the TriFoiler was getting close to that speed, though it suffered from cavitation problems.
While we may never see 45 knots on a cruising foil, it should be possible to cram some accomodations into a sailing foil - even if it would never be practical as a production boat. (You have a better background in this than I do though. I'm just an ME and avid sailor)
And, just for the record, this boat is NOT a catamaran. Cats have two hulls. This is (loosly) a Tri.
Never attribute to malice what can as easily be the result of incompetence...
Does anyone have any web pages that are more specific about the technical aspects of construction, such as material composition and so forth? The fact that this craft looks to be capable of 50 knots (92.60000000000001 km/h or 53.895mph thanks to Suntron Velocity Conversion) means that it would have to be constructed out of some pretty space-age type of materials (Carbon Steel, Titanium alloys and Carbon Fibre Composite come to mind here). The problem with the link provided by Slashdot is, besides the grammar difficulties involved in the translation from French (or any other language for that matter) to English, is that the details are sketchy and therefore it amounts to little more than your average press release. So if anyone has any interesting info they can post here, then go right ahead.
At any rate, I think the fact that this design was assisted by such large organisations as EADS (European Aeronautic Defence and Space Company) and CNES (Center National Space Studies) means that there's some pretty serious money being invested in this project. Also, the expertise being invested here is also amazing, given that the project has backgrounds in such high-tech fields as aeronautical and space engineering. So it's very likely that this will be more than a flash in the pan and that this will pave the way for bigger and more ambitious projects.
Self Bias Resistor
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When the pin is pulled, Mr. Grenade is no longer our friend.
OK, I have to go soon, so just a quick note:
, so 45 knots won't even get them the speed record. YPE claims a top speed of 54 knots, and to be honest I believe them. Even if they are Australians.
45 knots on a sailing hydrofoil with, like, cabin and somewhere to make a cup of coffee? I think not. Without going into details just accept that I went to University *just* to study this problem (I came to computing through writing fluid dynamics code) and you can take it from me that it won't be happening.
Thing 2: Current speed sailing record is 46.52 knots, held by Yellow Pages Endeavour (http://www.mko.freesurf.fr/innovoile/YPE_e.html)
Dave
I write a blog now, you should be afraid.
I love it, maybe we can make the foil into semiconducters, write an assembler language, then port linux and cluster it
"If a man watches 3 football games in a row he should be declared leagaly dead" - A
It's an interesting thought, but I think you're missing the point of supercavitation. Supercavitation is only truly effective (and truly possible) with vessels that are completely submerged in water (eg. submarines, torpedoes and the like). It works by creating a renewable pocket of air around the vessel, so that very little of the liquid touches the surface of the vessel. This reduces the vessel's viscous drag (bearing in mind that the resistance of water is somewhere in the order of 1400 times that of air) and allows it to travel much faster. This isn't the sort of thing that can't be done with a partly submerged vessel, as is the case here.
If you're interested in learning more about the specifics of supercavitation, then is an article on the Scientific American website and two articles on Slashdot (here and here). It should be interesting to see what the possible future applications of this technology would be. As always any constructive criticism is welcome.
Self Bias Resistor
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When the pin is pulled, Mr. Grenade is no longer our friend.
There is a page on the Alstom site (an official sponsor of the project) here.