[HN Gopher] Fastest sailboat: Two wild designs
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Fastest sailboat: Two wild designs
Author : clouddrover
Score : 119 points
Date : 2023-10-08 13:00 UTC (9 hours ago)
(HTM) web link (newatlas.com)
(TXT) w3m dump (newatlas.com)
| wolverine876 wrote:
| 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?
| adolph wrote:
| 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...
| TomK32 wrote:
| 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.
| wolverine876 wrote:
| The motorboats have all that engineering, testing, and
| regulation I talked about. Airplanes go even faster, but I
| know how safe they are.
| is_true wrote:
| It's a kite surf, but with a boat instead of a table. They are
| starting with small kites, so I would try it.
| littlestymaar wrote:
| 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).
| wolverine876 wrote:
| 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.
| littlestymaar wrote:
| > 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.
| Someone wrote:
| > 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.
| medymed wrote:
| 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.
| wolverine876 wrote:
| 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.
| mk_stjames wrote:
| 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).
| trillic wrote:
| 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.
| moffkalast wrote:
| 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.
| hadlock wrote:
| 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.
| zardo wrote:
| 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.
| hbarka wrote:
| Real source:
|
| https://sp80.ch/
|
| https://syro.co/en/speed-record/
| brucethemoose2 wrote:
| 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.
| hbarka wrote:
| 1. No proper citing.
|
| 2. The site looks like a hot mess because of their use of
| Taboola links.
| brucethemoose2 wrote:
| 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.
| hbarka wrote:
| 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.
| brucethemoose2 wrote:
| 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.
| hbarka wrote:
| Any personal favorites for news and current events?
| brucethemoose2 wrote:
| I read Axios pretty regularly because the site is
| exceptionally clean.
|
| Other than that, I tend to stick to niche sites.
| gumby wrote:
| 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.
| trillic wrote:
| 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.
| gumby wrote:
| 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.
| mechhacker wrote:
| Hydrofoils have been exploding in popularity in watersports. It
| used to be seen as a thing to do on light wind days, because it
| lets you go faster than the board usually limits you if you can't
| get hydroplaning. Hydroplaning takes a lot more wind power than
| hydrofoiling.
|
| 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.
| jimnotgym wrote:
| 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.
| tharax wrote:
| The sport is much more interesting for spectators when the top
| speed is 50-70km/h than when it's 10-20km/h
| philips wrote:
| Personally as long as there are graphic overlays and good
| commentators I think it can work at a lower speed.
| mark_l_watson wrote:
| 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.
| sand500 wrote:
| I wonder if it's possible to do a sailboat that lifts above the
| water entirely and stays in ground effect.
| binarymax wrote:
| There are already hydrofoil sailboats - is that what you mean?
| https://en.m.wikipedia.org/wiki/Sailing_hydrofoil
| clort wrote:
| 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.
| dragonwriter wrote:
| Hydrofoils don't lift entirely out of the water.
| yread wrote:
| 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.
| DelaneyM wrote:
| 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.
| dragonwriter wrote:
| 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).
| lambdatronics wrote:
| 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...
| coryrc wrote:
| 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.
| LeifCarrotson wrote:
| 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.
| Someone wrote:
| 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')
| coryrc wrote:
| 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.
| RantyDave wrote:
| 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.
| twp wrote:
| 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.
| antod wrote:
| 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.
| [deleted]
| patall wrote:
| 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)
| littlestymaar wrote:
| 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.
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(page generated 2023-10-08 23:00 UTC)