Fastest sailboat: Two wild designs(newatlas.com)
newatlas.com
Fastest sailboat: Two wild designs
https://newatlas.com/marine/syroco-sp80-testing/
92 comments
That is accurate, however, once within the same high wind and weight, hydroplaning gets ahead. That is due hydrofoil drag effect being so much higher than a regular fin. Same reason why windsurf speed record is 55kts while the windfoil record is somewhere near 37kts today.
IIRC Thomas Goyard hit 41kts on the foil, but may not be "official".
The speed canals where they hit really high speeds on fins are in special areas that most people will never be able to experience that have no wind disruptions and are very shallow canals to keep the chop down like in Luderitz, it isn't an open water speed: https://www.youtube.com/watch?v=jt3DQNUJXkc
The races, which have fin and foil against each other, have been in open water state (more real world for 99% of windsurfers), and in those conditions fin vs. foil are very competitive, with foils pulling ahead in the turns due to a lot less resistance and better ability to get back upwind compared to a fin. There's been a lot of debate on even allowing them to compete in the same races as they currently are allowed. They can both do 30ish knots in the same conditions, with the foilers getting away with smaller sails. https://www.youtube.com/watch?v=jsUDkg2d5tE
The speed canals where they hit really high speeds on fins are in special areas that most people will never be able to experience that have no wind disruptions and are very shallow canals to keep the chop down like in Luderitz, it isn't an open water speed: https://www.youtube.com/watch?v=jt3DQNUJXkc
The races, which have fin and foil against each other, have been in open water state (more real world for 99% of windsurfers), and in those conditions fin vs. foil are very competitive, with foils pulling ahead in the turns due to a lot less resistance and better ability to get back upwind compared to a fin. There's been a lot of debate on even allowing them to compete in the same races as they currently are allowed. They can both do 30ish knots in the same conditions, with the foilers getting away with smaller sails. https://www.youtube.com/watch?v=jsUDkg2d5tE
Do I understand correctly that 40 knots is about 75 km/h? That sounds like a pretty dangerous speed on just a surfboard with no protective gear.
Yup, that's the speed. It can be dangerous. During races they are required to wear impact vests and helmets.
Another innovation is a new kind of harness for the connection to the sail that releases above a certain force. A lot of the injuries are related to still being attached to the sail and being thrown into it during the crash, where you hit the hard carbon boom or mast instead of being flung clear into the water. That harness prevents that kind of catapult.
Another innovation is a new kind of harness for the connection to the sail that releases above a certain force. A lot of the injuries are related to still being attached to the sail and being thrown into it during the crash, where you hit the hard carbon boom or mast instead of being flung clear into the water. That harness prevents that kind of catapult.
For the one design, a supercavitating foil is mentioned. There have been torpedoes that use supercavitation sustained by onboard gas-generators feeding strategically located ports on the skin.
But that begs the question- would that type of cavitation induction be considered 'cheating' in the sense of being used on a sailboat that is supposed to be solely powered by the wind? The gas bubbles wouldn't be providing thrust, but a stored bottle of gas or electric pumps or any other stored energy device is just that....
The line between what tech gets used and what isn't allowed in these completely unsanctioned 'record attempts' is interesting to ponder.
In this case, it seems they are using a passive system (it is possible to get a foil to supercavitate without extra powered manipulation).
But that begs the question- would that type of cavitation induction be considered 'cheating' in the sense of being used on a sailboat that is supposed to be solely powered by the wind? The gas bubbles wouldn't be providing thrust, but a stored bottle of gas or electric pumps or any other stored energy device is just that....
The line between what tech gets used and what isn't allowed in these completely unsanctioned 'record attempts' is interesting to ponder.
In this case, it seems they are using a passive system (it is possible to get a foil to supercavitate without extra powered manipulation).
A number of offshore records don’t allow the use of stored power not generated by a human. It’s common to see electric winches and hydraulic controls on 100 footers, with the diesel running the whole race to power the winches and hydraulics, saves on bodies. However the 100 footers designed to beat ocean records have more people and more winches as they must be entirely human powered.
See Comanche. After she broke a bunch of records her winches and grinding pedestals got pulled and hydraulics installed.
See Comanche. After she broke a bunch of records her winches and grinding pedestals got pulled and hydraulics installed.
A lot of large ships use air lubrication systems to reduce fuel use, it's typically a system of compressors connected to ports with lots of tiny holes at the bottom of the hull. As I understand it, it reduces effective wetted area and thus surface tension drag.
So if you used a wind turbine to drive the compressor then it's fair game I guess? Maybe that makes it more of a windmill ship than a sailboat though.
So if you used a wind turbine to drive the compressor then it's fair game I guess? Maybe that makes it more of a windmill ship than a sailboat though.
You could just have a dude on an exercise bike powering the compressor too. A well-conditioned athlete can sustain 300 watts, which is 0.4 HP, or enough to drive something like 2.5 cfm?
Some AC75 designs (The British one I believe), used cyclists as their grinders, to drive the onboard hydraulics.
Depends on the competition. The 2024 RRS disallow hull lubricant, but as you said, this is an unsanctioned record attempt.
If the pressure on the upper surface of the foil is below atmospheric, this could be used to suck air down a tube. I have no idea if this is feasible, or would be useful if it were.
I wonder if they are going fast enough for ram-induction to generate the pressures needed?
You could always generate the power for the compression using wind.
I always wonder: At those speeds, the occupants risk life and limb. In the videos everything is fine, of course; they don't usually show the failures. But if you're an occupant, how do you know whether to trust the machine?
It is new technology without a track record, on a bespoke machine without a track record. It's safety is unregulated and unresearched. The builder doesn't have the resources to do anything like the safety engineering, prototyping, testing, etc. that someone like Toyota or Airbus does. Even if the design is safe, the construction also lacks those resources.
I can imagine taking the risk if I knew the risk. I could imagine doing it if someone else I relied on knew the risk (e.g., as a test pilot for a major company or military air force). I'm not risk-averse; I've taken more than my share, including risking life and limb. How does someone decide to ride one of these?
It is new technology without a track record, on a bespoke machine without a track record. It's safety is unregulated and unresearched. The builder doesn't have the resources to do anything like the safety engineering, prototyping, testing, etc. that someone like Toyota or Airbus does. Even if the design is safe, the construction also lacks those resources.
I can imagine taking the risk if I knew the risk. I could imagine doing it if someone else I relied on knew the risk (e.g., as a test pilot for a major company or military air force). I'm not risk-averse; I've taken more than my share, including risking life and limb. How does someone decide to ride one of these?
The 150km/h they target is nothing compared to the speed records in motorboats. https://www.youtube.com/watch?v=nloF0eF-zFs
Here's some difference to the motorboats,those pointy tubes sitting on the water surface with a big (jet) engine in your back pushing you. The Vestas has its sail off to the side and even a foil still in the water which will give it stability. The sailboats with the kites are being pulled and I imagine in a situation where you cut the rope, the impact into the water is quite predictable and in a straight line, very different from the wild accidents of high speed motorboats.
Here's some difference to the motorboats,those pointy tubes sitting on the water surface with a big (jet) engine in your back pushing you. The Vestas has its sail off to the side and even a foil still in the water which will give it stability. The sailboats with the kites are being pulled and I imagine in a situation where you cut the rope, the impact into the water is quite predictable and in a straight line, very different from the wild accidents of high speed motorboats.
The motorboats have all that engineering, testing, and regulation I talked about. Airplanes go even faster, but I know how safe they are.
Out of the 13 people who have attempted the motorboat speed record since 1930, 7 have died in the attempt.
I guess those numbers explain why so few have tried.
Mind you, these are much higher speeds. I looked it up, and the motor boat speed record is over 500 km/h.
Mind you, these are much higher speeds. I looked it up, and the motor boat speed record is over 500 km/h.
They do now but not when they first reached those speeds.
Perhaps by riding other super-fast sailboats and surviving so far.
Analogously that is the only way I could rationalize the Wright brothers attempting an airplane flight (after surviving many glider flights), which otherwise would seem an insane proposition.
Analogously that is the only way I could rationalize the Wright brothers attempting an airplane flight (after surviving many glider flights), which otherwise would seem an insane proposition.
The Wright brothers were developing a major advance for humanity; I might take more risks for that. Also, their airplane was moving quite low and slow - much less risk than these boats, I would guess.
Finally, they were the engineers of their plane - they probably knew the risks well. Maybe that describes these watercraft pilots too.
Finally, they were the engineers of their plane - they probably knew the risks well. Maybe that describes these watercraft pilots too.
Syroco describes their attempt the same way. Sea transport has a huge environmental footprint and has changed very little in the last 50 years.
The Wright Brothers' plane carried neither passengers nor cargo, yet it presaged an entire industry of air travel. Likewise, these speed-record boats will only demonstrate a new technology. But likewise, they might transform an enormous industry.
The Wright Brothers' plane carried neither passengers nor cargo, yet it presaged an entire industry of air travel. Likewise, these speed-record boats will only demonstrate a new technology. But likewise, they might transform an enormous industry.
That's true. I've been hearing a lot about using kites for large cargo ships. They'll never be going that fast, but the tech does serve a very valuable purpose.
> Finally, they were the engineers of their plane - they probably knew the risks well. Maybe that describes these watercraft pilots too.
I think that is the key here. Don’t compare these to a reliable production airplanes, they are more akin to a prototype plane.
With prototype airplanes we call the pilots a special name: “test pilots”. But that is just because with most airplane designs there is an expectation that they once will graduate out of testing and will be piloted by regular pilots. But some airplanes never do that. They were only ever meant to demonstrate some principle or explore some new frontier. Same with these sailboats, their crew are “test pilots”, and they perform a test program to gradually validate the performance and safety of the craft. And most likely they will be only ever crewed by the crew who did that program.
So what does it mean that they are “test pilots”. They all probably have a lot of experience with all kind of sailboats and especially fast ones, and then they have a proven track record of having a good intuitive understanding of the physics involved. If all you ever did is to capsize a dingy on a local lake you are probably not getting this job.
And then test pilots get access to the engineers designing the craft and they talk a lot about expected performance. There are all kind of curves and diagrams one can inspect to understand how the craft is likely going to handle.
And then they don’t just leave the pier for the first time and run a world record speed. They first go relatively slow, and only when they are certain they understand how the craft behaves do they try to go faster and faster. This might also mean that they are initially very picky about the conditions they launch into, and as they gain more experience they can “expand the envelope” and try gnarlier weather.
Then of course they prepare for adverse events. They wear appropriate personal protective equipment, have a plan what they do if they are thrown overboard or capsize, and they also most likely have rescue boats at the ready to save them if something goes wrong.
And then on top of all of that they all probably have a psychological makeup where they value going fast, and being the first more than being safe. Even with all the safety precautions and mitigations and good design activities like these are risky. People who all above wish for a long and peaceful and slow life are probably not going to gravitate towards these jobs.
I think that is the key here. Don’t compare these to a reliable production airplanes, they are more akin to a prototype plane.
With prototype airplanes we call the pilots a special name: “test pilots”. But that is just because with most airplane designs there is an expectation that they once will graduate out of testing and will be piloted by regular pilots. But some airplanes never do that. They were only ever meant to demonstrate some principle or explore some new frontier. Same with these sailboats, their crew are “test pilots”, and they perform a test program to gradually validate the performance and safety of the craft. And most likely they will be only ever crewed by the crew who did that program.
So what does it mean that they are “test pilots”. They all probably have a lot of experience with all kind of sailboats and especially fast ones, and then they have a proven track record of having a good intuitive understanding of the physics involved. If all you ever did is to capsize a dingy on a local lake you are probably not getting this job.
And then test pilots get access to the engineers designing the craft and they talk a lot about expected performance. There are all kind of curves and diagrams one can inspect to understand how the craft is likely going to handle.
And then they don’t just leave the pier for the first time and run a world record speed. They first go relatively slow, and only when they are certain they understand how the craft behaves do they try to go faster and faster. This might also mean that they are initially very picky about the conditions they launch into, and as they gain more experience they can “expand the envelope” and try gnarlier weather.
Then of course they prepare for adverse events. They wear appropriate personal protective equipment, have a plan what they do if they are thrown overboard or capsize, and they also most likely have rescue boats at the ready to save them if something goes wrong.
And then on top of all of that they all probably have a psychological makeup where they value going fast, and being the first more than being safe. Even with all the safety precautions and mitigations and good design activities like these are risky. People who all above wish for a long and peaceful and slow life are probably not going to gravitate towards these jobs.
The Wright brothers were involved members of an international “glider” community and, yes, they won the race to be the first to successfully strap an engine to one and fly it.
But remember that the Wright brothers didn’t even try to patent “the airplane”. Their achievement (and patent) was about safely controlling an airplane so that it could fly. More than two years before their 1903 flight, Wilbur Wright gave a presentation in Chicago where he said “ As long ago as 1884 a machine weighing 8,000 pounds demonstrated its power both to lift itself from the ground and to maintain a speed of from 30 to 40 miles per hour, but failed of success owing to the inability to balance and steer it properly. This inability to balance and steer still confronts students of the flying problem, although nearly eighteen years have passed. When this one feature has been worked out, the age of flying machines will have arrived, for all other difficulties are of minor importance.”
But remember that the Wright brothers didn’t even try to patent “the airplane”. Their achievement (and patent) was about safely controlling an airplane so that it could fly. More than two years before their 1903 flight, Wilbur Wright gave a presentation in Chicago where he said “ As long ago as 1884 a machine weighing 8,000 pounds demonstrated its power both to lift itself from the ground and to maintain a speed of from 30 to 40 miles per hour, but failed of success owing to the inability to balance and steer it properly. This inability to balance and steer still confronts students of the flying problem, although nearly eighteen years have passed. When this one feature has been worked out, the age of flying machines will have arrived, for all other difficulties are of minor importance.”
> In the videos everything is fine, of course; they don't usually show the failures
I’m not sure they can keep video secret if accidents happen that cause serious injuries or death.
There are plenty of failure videos for the gigantic trimarans used in the America’s cup (search term “America's cup trimaran capsize”), and I think not all of them were in public races.
I’m not sure they can keep video secret if accidents happen that cause serious injuries or death.
There are plenty of failure videos for the gigantic trimarans used in the America’s cup (search term “America's cup trimaran capsize”), and I think not all of them were in public races.
People have died in F50 cat crashes.
Is it that much risker than mountainbiking, offtrack skiing or base jumping? Relatively few people would take the risk of practicing extreme sport either, but there are still thousands of people that do.
It's not too different from people testing the first hot air balloons, planes or helicopters (albeit much less risky, still).
It's not too different from people testing the first hot air balloons, planes or helicopters (albeit much less risky, still).
Comparing this to off-piste skiing or mountain biking is not fair at all. You can view avalanche predictions, sample the snow pack, and take safe and slow lines that go perpendicular to the faults when skiing. Biking you can use hydraulic disk brakes, deliberately lay the bike down and slide out, plus you should be wearing a full face helmet, spine + neck protector, and other armor.
Unless you are actively trying to set a speed record or win a race there is far less danger.
> Unless you are actively trying to set a speed record or win a race there is far less danger.
Well, that's also exactly what we are talking about here…
Also you're talking to someone who broke his own shoulder earlier this year while doing some very easy off-piste skiing earlier this year so I can absolutely assure you that danger is just a small mistake away even if you aren't doing insane stuff.
Well, that's also exactly what we are talking about here…
Also you're talking to someone who broke his own shoulder earlier this year while doing some very easy off-piste skiing earlier this year so I can absolutely assure you that danger is just a small mistake away even if you aren't doing insane stuff.
My concern is not the amount of risk, but that the amount of risk is unknown.
Someone who has done a lot of skiing / parachuting can estimate well the risks of offtrack skiing and base jumping, plus lots of people have done it before and can inform you, plus the technology used (skiis / parachutes) have very long track records and known performance.
(Mountain biking doesn't seem to be in the same category, but whatever.)
> It's not too different from people testing the first hot air balloons, planes or helicopters (albeit much less risky, still).
Yes, good analogies.
Someone who has done a lot of skiing / parachuting can estimate well the risks of offtrack skiing and base jumping, plus lots of people have done it before and can inform you, plus the technology used (skiis / parachutes) have very long track records and known performance.
(Mountain biking doesn't seem to be in the same category, but whatever.)
> It's not too different from people testing the first hot air balloons, planes or helicopters (albeit much less risky, still).
Yes, good analogies.
> My concern is not the amount of risk, but that the amount of risk is unknown.
It's not really unknown: it's really high and you better hope you don't mess up or you're dead/maimed. Sure here the “don't mess up“ happens mostly at design/build time instead of during the execution, but at the end of the day you're risking your life hoping you're not making a mistake. That's definitely not for everyone.
It's not really unknown: it's really high and you better hope you don't mess up or you're dead/maimed. Sure here the “don't mess up“ happens mostly at design/build time instead of during the execution, but at the end of the day you're risking your life hoping you're not making a mistake. That's definitely not for everyone.
It's a kite surf, but with a boat instead of a table. They are starting with small kites, so I would try it.
Risk is a continuum. When it is unknown the people interested in risk accept it. Eventually people learn the risk model and change behavior based on that. As an example of newly known:
All models of Onewheel electric skateboards are being recalled after the maker Future Motion received reports of four deaths of users between 2019 and 2021 and multiple reports of serious injuries.
https://www.cnn.com/2023/10/01/us/onewheel-electric-skateboa...
All models of Onewheel electric skateboards are being recalled after the maker Future Motion received reports of four deaths of users between 2019 and 2021 and multiple reports of serious injuries.
https://www.cnn.com/2023/10/01/us/onewheel-electric-skateboa...
Real source:
https://sp80.ch/
https://syro.co/en/speed-record/
https://sp80.ch/
https://syro.co/en/speed-record/
NewAtlas kinda looks like a PR reposter at a glance, but they are actually a great site. They are proper journalists with a soul, who reach out to the sources, test things, hunt down leads, and generally write stuff like its not written by a LLM.
What I am saying is that I don't feel bad about "skipping" the original source like most soulless cloners you see on the written internet these days.
What I am saying is that I don't feel bad about "skipping" the original source like most soulless cloners you see on the written internet these days.
1. No proper citing.
2. The site looks like a hot mess because of their use of Taboola links.
2. The site looks like a hot mess because of their use of Taboola links.
Its just minor Google banner ads for me and a Taboola bar at the very bottom. That's about as good as it gets these days, even on sites like APNews.
Yes, the Taboola hot mess is also on CNN. How did this awful clickbait platform become so ubiquitous even on sites where you expect a level of content scrutiny.
Written online journalism has been on the decline for like a decade because of video, social media, the ad/spam arms race, SEO exploitation and such. They have to use Taboola to pay the bills, they have no other choice.
Any personal favorites for news and current events?
I read Axios pretty regularly because the site is exceptionally clean.
Other than that, I tend to stick to niche sites.
Other than that, I tend to stick to niche sites.
I cannot comprehend how people are using web in 2023 without ad-blocking.
I used to have a sloop (J/109) and once I got it up to 17 knots surfing* downwind. It was exhilarating but terrifying. There’s no way I would ride on a sailboat going 60kts+.
* even displacement hull boats can surf - you let a wave come up behind you then you turn down the face of the wave and accelerate - it’s a blast surfing a 5 ton boat.
* even displacement hull boats can surf - you let a wave come up behind you then you turn down the face of the wave and accelerate - it’s a blast surfing a 5 ton boat.
It also depends on the size of the boat. I've been on a large yacht catamaran[0] that did 16 knots. It was fast, but not terrifyingly so on a boat that big. I bet it could go quite a bit faster if the owner was willing to push it, but he wasn't because it was also his home.
[0] 15m long and 7m wide.
[0] 15m long and 7m wide.
That first one (the current record holder?) still looks surprisingly traditional, with a recognisable mast and all. A couple of decades ago I read about a record targeting "sailing boat" that really stretched the definition of both sailing and boat; it looked more like a glider plan on a central stilt that would flip over on every tack and was only able to sail upwind. (Perhaps counter-intuitively, these speeds are only possibly upwind; you can't go downwind faster than the speed of the wind.)
So I'm a bit surprised to see the current record holder still looking recognisably like a sailing boat. That trimaran contender still looks pretty normal, although if it uses a kite, that's definitely interesting.
But that Syroco! That's really pushing the definition of sailing and boat beyond recognition. It looks closer to kite surfing. Or a glider with a kite instead of wings that only seems to be touching the water because otherwise it wouldn't count as a sailing boat anymore but as a plane. Though I suspect that board/hydrofoil is still necessary to control the course.
So I'm a bit surprised to see the current record holder still looking recognisably like a sailing boat. That trimaran contender still looks pretty normal, although if it uses a kite, that's definitely interesting.
But that Syroco! That's really pushing the definition of sailing and boat beyond recognition. It looks closer to kite surfing. Or a glider with a kite instead of wings that only seems to be touching the water because otherwise it wouldn't count as a sailing boat anymore but as a plane. Though I suspect that board/hydrofoil is still necessary to control the course.
This is incorrect, for a long time now the latest sailing yachts have been able to sail downwind faster than the speed of the wind, in fact averaging 1.8X the speed of the wind with peaks of 2.0X the speed of the wind. There has been considerable research in this area. See here: https://en.wikipedia.org/wiki/High-performance_sailing#Multi...
Is that straight downwind or broad reach? Broad reach I can understand, because there's still a sideways component to the wind. If it can also be done straight downwind, I'd love to understand how.
I doubt this is how sailboats are doing it (if they're doing it) but one way is (I think) to make the airfoil itself cut across the wind while the "boat" goes straight downwind. See these videos:
https://www.youtube.com/watch?v=jyQwgBAaBag
https://www.youtube.com/watch?v=yCsgoLc_fzI
https://www.youtube.com/watch?v=jyQwgBAaBag
https://www.youtube.com/watch?v=yCsgoLc_fzI
The explanation in that first video with ships sailing on a cylindrical ocean being analogous to a propeller was really great. But from what I understand, that's not how their car actually works, because they're actually powering the propeller from the wheels and expecting the propeller blowing backward to push the car forward, and not the wind moving past the blades in just the right way to pull it forward.
I think my analogy still holds: the vehicle in the video wouldn't work if the wheels were used through a mechanism to simply push the air directly backward. That would be like having a square-rigger-style sail and using a fan to blow air at it.
Instead, the thing that makes the vehicle work is the ability to use the mechanical(?) advantage of the prop slicing through the air at an angle to improve efficiency. Just as regular sails working at an angle to the wind can move downwind faster than a balloon (illustrated in the video) the angled prop can be used to move the vehicle downwind faster than the wind, but only by moving at an angle to it.
Instead, the thing that makes the vehicle work is the ability to use the mechanical(?) advantage of the prop slicing through the air at an angle to improve efficiency. Just as regular sails working at an angle to the wind can move downwind faster than a balloon (illustrated in the video) the angled prop can be used to move the vehicle downwind faster than the wind, but only by moving at an angle to it.
I assume that these are like the rocket motor cars* that race a straightaway on the salt flats. I.e. not steerable boats that can travel outside a narrow point of sail.
Would be great if I were misunderstanding!
* I struggled to find a better word than this obsolete phrase, but I’m talking about vehicles far beyond a stock car with a rocket attached.
Would be great if I were misunderstanding!
* I struggled to find a better word than this obsolete phrase, but I’m talking about vehicles far beyond a stock car with a rocket attached.
Correct. Dont use them on anything but flat water.
Check out the Foiling IMOCA 60s. They regularly top 30 knots in the middle of the ocean. Highly maneuverable.
The 100 foot foiling ocean Trimarans are a bit faster with top speeds over 40 and 24 hour averages in the high 30s with a crew of 5 or 6, often sailed Solo.
Check out the Foiling IMOCA 60s. They regularly top 30 knots in the middle of the ocean. Highly maneuverable.
The 100 foot foiling ocean Trimarans are a bit faster with top speeds over 40 and 24 hour averages in the high 30s with a crew of 5 or 6, often sailed Solo.
There were attempts at hydrofoil windsurfers in the '80s but the materials technology wasn't yet good enough so they would usually break after one or two uses. Some good reports in SAIL back then.
About 30 years ago my Dad’s friend Nils Muench did this competition. He built a hydrofoil catamaran that would only sail on a reach, so a power boat would tow it into position. I think Nils’ sailboat got up to about 45 MPH.
I suppose these are technically sailboats by some definition, but they look like oversized kite boards to me, with one having more structure to the "sail" than the other.
It's not actually a sailboat speed record, it's a sailing in water speed record. It's gone back and forth a couple times between boats, windsurfers, and kite boarders.
I wonder if it's possible to do a sailboat that lifts above the water entirely and stays in ground effect.
Yes, but.
You have to remember that speed sailing is effectively an efficiency competition. The theoretically perfect sailing machine would a foil in the air and a foil in the water connected by something with as little weight and drag as possible. Syroco are alarmingly close to making this happen.
An interesting choice to use a supercavitating foil. "Back in the day" there was an assumption that hydrofoils could never run above 50 knots due to cavitation, but the America's Cup people seem to do that (just). There are nice consistent supercavitating surfaces but they're called propellers.
Either which way, my money is on syroco.
You have to remember that speed sailing is effectively an efficiency competition. The theoretically perfect sailing machine would a foil in the air and a foil in the water connected by something with as little weight and drag as possible. Syroco are alarmingly close to making this happen.
An interesting choice to use a supercavitating foil. "Back in the day" there was an assumption that hydrofoils could never run above 50 knots due to cavitation, but the America's Cup people seem to do that (just). There are nice consistent supercavitating surfaces but they're called propellers.
Either which way, my money is on syroco.
My precise thought was "Aw, Syroco's got this, if it doesn't murder everything that gets bolted inside of it.". It's like the engineers made a force vector diagram and just stopped there.
Funny that nobody mentioned it so far, but yes, you can do that indeed. And it is almost certainly even now already the fastest type of sailing. It is called ice-sailing :) Even hobbyists reach 80-100 km/h ice wind sailing. (Note though that technically no ground effect is involved)
For a sailboat to work at all, you need a part of it that “stick” in the water.
Wind-powered “planes” can't work for that reason (and no, gliders aren't powered by the wind, and you can't have a ground-effect glider either)
So the best you can do is have just a foil that sticks in the water while having everything else out, which is basically what every modern race boat is doing.
Wind-powered “planes” can't work for that reason (and no, gliders aren't powered by the wind, and you can't have a ground-effect glider either)
So the best you can do is have just a foil that sticks in the water while having everything else out, which is basically what every modern race boat is doing.
Once it lifts above the water there's no lateral resistance, so it's not going to make way abeam or beating, just downwind. Having said all that, I think WIG is a factor in the CFD sims of Sailrocket 2, just not anything like the primary lifting force.
No, you need lateral resistance from something in contact with the water. Otherwise you just get blown downwind until the point your speed relative to the wind (apparent wind) drops away and you're not getting enough lift any more.
There are already hydrofoil sailboats - is that what you mean? https://en.m.wikipedia.org/wiki/Sailing_hydrofoil
No, ground effect is (AFAIK) when the depth of the wing (fore-aft) is greater than the distance above the surface it is flying over. The leading edge of the wing creates a pressure wave that reflects back from the surface and provides lift to the whole wing. You can see it with birds like pelicans which skim the water for a long way without needing to flap at all. I don't know if this would enhance the speed at all though, there are presumably other effects involved with going faster.
I think they mean like flying as in not touching the ground/water. Sounds doable: these speeds are usually ground speeds so the applied wind speed (ground speed+wind speed) could reach 100kmh which is enough for a sail plane.
As other replies have mentioned, you need to push against the water to position the windfoil to produce thrust. Otherwise you're just being pushed by air, and you're limited by windspeed.
Sailboats can go many times the speed of the wind they're in.
Sailboats can go many times the speed of the wind they're in.
Hydrofoils don't lift entirely out of the water.
So, like, a wing-in-ground-effect craft using sails for thrust, or a hovercraft that uses sails for (horizontal) thrust?
Seems like the sails would be too big of an aerodynamic compromise for the former, but the latter might work (though it would be kind of silly).
Seems like the sails would be too big of an aerodynamic compromise for the former, but the latter might work (though it would be kind of silly).
Downwind: probably.
Otherwise, no, because it's the interaction between the keel and water which allow you to sail other points i.e. broad reach.
Otherwise, no, because it's the interaction between the keel and water which allow you to sail other points i.e. broad reach.
Downwind wouldn't work, you'd just be a very fancy leaf moving with the breeze with no control. It's really the differential between the wind and the water (not so much the keel) that allows the sail to exert a force on the vehicle. Once you're going downwind at the speed of the wind with no reference to the water, you might as well be in still air.
Wind speed typically increases with height and wind direction varies, so you could have a sail or kite that’s in faster wind, but I doubt the difference is large enough in practice.
(in theory, I think a kite up in the jet stream and a fairly large sail near ground level would work for some definition of ‘work’)
(in theory, I think a kite up in the jet stream and a fairly large sail near ground level would work for some definition of ‘work’)
Two sail planes on a tether should be able to do it. How the pilots are going to get good at it without getting killed is probably a bigger problem than constructing it.
It's the keel that makes it possible to sail upwind in any useful sense. There are functional equivalents possible e.g. a catamaran can have very narrow-but-deep hulls, but it's the the fact that a keel provides very little drag straight ahead and a lot at 90 degrees which allows you to sail close-hauled.
I remain unconvinced it's impossible downwind, given gliders and parasailing work.
I remain unconvinced it's impossible downwind, given gliders and parasailing work.
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Only if there's enough wind shear between the aircraft and kite altitudes... kinda like dynamic soaring [0] but without the need for the aircraft to jump back and forth between the two regions. You'd probably need to use a sailplane or something to get high efficiency flight at low speeds. I think it would be super dangerous, b/c in order to access the strongest differential wind speed, the craft would need to be very low to the ground (just a few meters).
[0] https://en.wikipedia.org/wiki/Dynamic_soaring#Manned_aircraf...
[0] https://en.wikipedia.org/wiki/Dynamic_soaring#Manned_aircraf...
Fundamentally, sailing is extracting movement from the relative movement of two fluids. This is done by putting an vehicle at the boundary of the fluids with a wing in each fluid in such a way that the vehicle moves.
If you use wing-in-ground-effect then you are in a single fluid, where there is no relative movement, so you cannot extract energy from the relative movement.
Put more simply, you need something to push against, so you need at least part of the vehicle in each fluid.
If you use wing-in-ground-effect then you are in a single fluid, where there is no relative movement, so you cannot extract energy from the relative movement.
Put more simply, you need something to push against, so you need at least part of the vehicle in each fluid.
You can also extract energy by moving between two fluids in relative motion.
If you count that as sailing, this is the fastest sailing vessel.
https://youtube.com/watch?v=4eFD_Wj6dhk
If you count that as sailing, this is the fastest sailing vessel.
https://youtube.com/watch?v=4eFD_Wj6dhk
That must be the most amazing RC vehicle flight I have ever seen footage of; thank you for the link!
Sail boats and trebuchets are two of the all time best constrained optimization problems. Such diversity!
Trebuchets? Tell me more :-P
All spinnaker all the time. How do they go into the wind?
Can we finally get rid of those ridiculous Americas cup yachts? Using a bunch of humans on board to generate hydraulic power either by hand cranking or pedaling is plain ridiculous. One skipper, the rest of the crew 'grinding'... that shouldn't make me chuckle but it does. At least when they were pulling ropes it wasn't just braun involved.
The sport is much more interesting for spectators when the top speed is 50-70km/h than when it’s 10-20km/h
But, they've been pushing the windsurf gear to 40kts on hydrofoils. That's without adjustable control surfaces like these boats, just steering with body weight and sail trim. I personally have gone 23kts or so and it feels much much faster than when you're on a fin, and you are constantly moving your weight to keep from slapping the water or getting too high for the foil then crashing.