PARTNERS - SkySails : Towing a vessel with a kite
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- čas přidán 21. 08. 2024
- SkySails is a partner of the Race for Water, thanks to their knowledge the vessel is equiped with a kite which allows the Race for Water to cross oceans notably with the wind.
The Race for Water Foundation is dedicated to the preservation of the water and the oceans in particular. Today, seriously under threat from plastic pollution, it is imperative that this essential resource for life is protected.To prevent plastic waste from reaching the waterways and oceans by developing social models and business models that give value to plastic waste and hence encourage its collection.
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To those concerned that their wasting power by flying in a figure eight. They’re not. Flying the kite like that makes it travel faster relative to the wind. This greatly increases the thrust it generates. A bit like how those America’s Cup boats can actually sail faster than the wind, because moving the sail across the wind increases the effective wind speed.
Was more concerned that theyre wasting power by not having a bigger sail on the ship itself.. 🤔
@q.e.d.,
Any one that's "concerned" about wasting anything on this planet is delusional enough to think it really matters.
They believe they'll get a medal and accolades when they return to the Universe. Dreams are nice . . . ☆
Making sailing more difficult than it has been for thousands of years in order to protect the oceans that are taking care of themselves. Good job kids.
Since when has sailing not been extremely tedious and difficult as is? Constantly relining shit and re-attaching things to different places because the wind changed a tiny bit.
or catch the greater winds higher up and without all the rigging. Sounds easier to me.
Propulsing is not a word. Propelling is the one you searched so long and hard for
The different between sounding and being smart.
@@11kungfu11 "difference"
@@weatheranddarkness touch type fail.
Twas my first thought, though propulsing is in fact a word just the wrong word...
propulse. Verb. (third-person singular simple present propulses, present participlepropulsing, simple past and past participlepropulsed) (obsolete) To repel; to drive off or away.
Yup.. These people just proved that for ~ 5mln$ it's possible to attach kite to the boat..!
Yet failed to learn the words to describe what they actually intended to do..!
Kevin Costner in waterworld already did this and his was way better being shot out of a cannon and no wasteful figure eight robotic pattern, and he designed and built his in a post-apocalyptic water wasteland... Smooookers!!
The figure-8 is the opposite of "wasteful" - it generates a lot more power.
True Story, my wife and I lived on the Big Island and were married by Sheldon Weldon, who fabricated much of Costner's boat in Water World. We visited his home and he was fascinating.
@@haroldrhodes2610 I know Sheldon ~ He got me a job making props for Mike Milgrem on set. We were extras , my wife and I. She even had a line in the movie which she never got any extra pay for. She fills the screen and says "Kill him kill him kill him ! " Pretty funny. The star of that film was the BOAT which I never got tired of studying up close. All my friends from Malibu were the stunt crew from Stunts Unlimited. That was a fun job...Costner shamed himself and ruined some lives over there. Everybody knew what was happening. I found out a little late. The movie business is a squalid seedy affair... But I dug lots of the crew... like a high school reunion.
thank you so much for this excessive engineering feat. this is an idea ive kicked in my head for so many years, it's amazing to see the answers in front of me so clearly... the figure 8, the strobe light, the ship-based localisation.... truly you've saved me countless hours of mental wrangling and i feel like buying a winch and arduino for my boat!!!
I had this same idea. I can see now it's not practical. I'm glad someone with money tried this concept and this video is very valuable in demonstrating the drawbacks of such a concept. The old way of capitalizing on wind power with a jib and main sail is still the best way in my opinion.
Perhaps it just needs a bigger sail for the boat size
Not practical, you say... czcams.com/video/pYv6k5A-kHg/video.html
@@MrFurriephillips I know right! I've seen some screaming kiteboats
There are circumstances where mast and sails are not practical. Try modern cargo handling methodology with a couple of masts in the way. This device can be fitted to a ship’s forecastle, folds away completely and is used as a fuel saving device. The ship steams to her normal schedule with the kite used when conditions are suitable. I read somewhere that given a fuel reduction of about 10%, the device could pay for itself in under 2 years. That could be bullshit for all I know but I don’t think you should regard this as designed to be anything more than auxiliary power.
Apart from not impeding cargo handling as masts do, kites have other advantages over sails. Depending on where you attach the line, you can completely eliminate any heeling moment. You can fly the kite at altitudes where the wind is both stronger and steadier.
There’s a video of a short race between a number of different vessels including a windsurfer, a foiling cat a three-man-trapezing cat and a foiling kite boarder. Not only did the kite board win by a country mile, but he was both footing faster and pointing higher than any of the rest when hard on the wind.
yesssssssssssssss , make it bigger. 25knots go go
I've been trying to figure out the recovery procedure and finally figured it out. Looks like that recovery line on the leading edge of the sail going to the top of the mast, stays attached to the sail at all times. You can just make it out in a slack state at 2:13. Very cool technology.
Great work, I can see the 'ahead vision'. Dont get stuck in "this is what we've done before". Keep it up.
Fantastic technology! Keep going ! I am very impressed. Now that you have the knowledge put 3 or more together and I bet that boat cruises for a long time a good speed! Go for it ! What a break through in sailing Tech. Good for you !
Umm no Gary it's an answer to a non existent problem .. I sail full time both kites and my liveaboard sailboat .. there are so many more efficient methods to move a large displacement vessel via the wind with NO technology required
I'm a little late to this conversation but "no technology" is an overstatement, for sure. Can you explain what you meant, Mitch? I kite and sail as well, and I'm sure kites are tools that haven't been used to their potential in displacement hull sailing. The right aspect ratio kite with a large area and suitability long line lengths may not have been attempted yet (even now 2 years after you wrote your post).
It’s like normal sailing but harder, slower, & more expensive! I like it👍
There is a good use for that idea, they do this same concept in the sport of “kite boarding.” So my question is. Why don’t they add an appropriate size kite to all life rafts in eluding it also in the survival gear of our navy pilots. An appropriate sized controllable kite would propel a survival raft more efficiently against an unfavorable current or towards a known land mass or away from drifting into enemy hands. Its compact and folds up neatly in a small space as part of the survival kit. Turns the raft into a sailboat instead of a drifting log.
william Burgos
Wonderfully obvious, or should be. 👍
Similar but different......why doesn’t every over-big-water aircraft have a device just under it’s skin that automatically deploys when submerged, inflates buoyancy devices, deploys a tethered helium balloon equipped with an antenna transmitting GPS coordinates of the impact location while a super-bright strobe light flashes from said balloon at several hundred feet altitude. Come to think of it, an almost identical device would be a nice addition to your suggestion.
You cannot tack or travel upwind at all with a kite while sitting on a raft. At a minimum, you would need a keel and rudder that can hold its position while you loop the kite. For snowkiting, the edges on our skis/board allow us to tack and travel upwind. For kiteboarding, our heel edge digs into the water to provide the resistance needed to tack. I have put 5m - 14m kites up over kayaks and can tell you from experience it will not work. Traveling downwind, on the other hand, works just fine for a few seconds until you approach wind speed, and the kite luffs and loses its power. You will fight to keep the kite looping, power will pick up, and be quickly lost as you speed up. Watch kiteboarders and snowkiters closely, and you will see they are traveling perpendicular to the kite at all times. In this video, it is clear they are also traveling (or attempting to travel) downwind. Why didn't the kite luff in this video as the vessel picked up speed? Two possibilities; either they only showed clips of the kite fully powered, or the kite never moved the vessel enough.
Because you need a keel for a kite to work. Otherwise its simply a parachute dragging you down wind. as long as there is resistance to keep them inflated. Kites aren't magic or new.
You don’t need a keel per se any lateral resistance works. Like the edge of a kiteboard, the hulls of a hobie 16 etc. A dedicated keel/centreboard is not necessary if the hull is shaped in certain ways
Thank god someone has finally found an emissions free way to harness the wind for maritime transport! Keep it up guys
Nothing new it call a sail boat, being around a few thousand year
@@JohnLee- you learn something new every day. Thanks!
That’s a UFO at night if I ever saw one. What a great and beautiful vessel that is
The original name of the boat was planetsolar and he do a world tour in 2012
Qui a inventé se concept c une idée de génie absolue
Look at the boat’s wake, totally not moving! Am i wrong?
I Think it is just aquadynamc Shaped
sailing doesn't make that big of a wake anyways. and its says the average speed is 5 knots which is 10kmh that wont make a much of a wake and on such a big boat its almost like not moving at all
Yea! Its not going anywhere!!! Lol!
Florian V.D.
Even at 5 there should be a wake. The waves are less then a foot! During a tack I slow down almost half speed about 4ish knots and I still can see a wake.
It seems that way to me too. The question I have is, With all those solar panels doesn’t it completely power the boat and charge a huge battery bank at the same time so you can run at night?
Wow! I am blown away. Never seen anything like this! Wow! Wow!
With all that performance I thought I was going to see the most massive kite. If you looked at the waves the boat wasnt even moving through them.
They're typically used to decrease consumption, not the sole mode of mobility. The newish Silent catamaran can reach their cruise speed of 8 knots with a combination of solar and one of these kites, without depleting their batteries. Large ocean going container ships use them as well.
Because the kite is moving through the air doing figure 8s it experiences true wind but also apparent wind (what you feel when you stick your hand out the window of a car on the highway) these two winds combine in strength and direction to make the wind the kite experiences up to 4x stronger than the real wind. This combined with the more efficient 3d wing shape makes kits about 10x more powerful than traditional sails given the same area
@@CrispyOkra The vessel is equipped with a lot of PV panels. Does it move by using electric motors and skysail wind power?
@@drzavahercegbosnaponosna5974
Yes.
As a kite-surfer myself, it looks like they are wasting a lot of energy doing figure eights. Get it going then park it at 45 degrees or somewhere around that.
That's one of the points I was trying to make in another thread. That and the foil on this vessel is only 40m2, it doesn't seem to catch enough wind to move the boat.
As kiteboarder you should know that moving and looping the kite generates enormous amount of energy. Also figure 8 because most of the time the kite was downwind and the boat would quickly catch up with the kite. It's basically like doing downwinder on kiteboard - constant looping and figure 8 or else the kite falls in the water. The kite is too small for the boat for any practical use and it would be too dangerous to run a larger overpowering kite without very responsive and sophisticated kite depower and control system.
search for kite-boat system online there is a commercial version for sale.. I think its a brilliant idea
The kite is just a lil bit small for that boat
and it it were bigger the way it was going it would pull the bow all over the place !!! giving a rough ride
Can't compare these 1:1, for two reasons: a) the kite is higher up where wind is about twice that closer to sea level, and b) the kite is moving in figure-8s which means it goes about 5x faster than the boat. Aerodynamic lift is proportional to airspeed - so mentally multiply the kite area by factor of 10 - seems big enough now?
They've achieved 20-30% fuel savings on ocean crossing *freighters* with this technology, I think you can trust them to size the kite correctly for this boat. :)
@@linolinco Would this work on a foiling catamaran?
@@HansKeesom I don't see why not. A kite causes far less heeling so a larger area can be flown than with conventional sails. Needs to be actively flown so (unless you have the fancy SkySails autopilot) probably be more of a racing thing. I reckon the next speed sailing world record could be taken by a foiling kiteboat.
I mean considering you can make the kite as big as the sky itself that is no reason why you shouldn't be able to go the exact speed af the wind on any given day. This is a baby kite though.
Experiments are great and these people deserve credit. The wide flat boat could have trouble in big wind/waves.
Wow. 2 minutes and 40 seconds but didn't tell us what it does. Oh, figure eights and has strobey lights?
Why figure 8's? Why can't it go higher and be stationary
Brilliant idea, With multiple computer controlled sails this could be expanded to multiple sails and work for all shipping, passenger and commercial. With commercial it would cut down on fuel costs and for passenger it could be the sole source of power when combined with solar. Good job.
Then it get hit with a bolt of lightining, on a dark broody sky, now they fucked, hang on dont worry, riase the kite an er avoid the lighting bolts and they er waves, and set a course for a safe harbour laughing my black as off, you must be in a warm room conceptualisng theorums about sextants watching your barometer,,,, get the actual fuck out of hear, those lilly livered deck swabs would buckle in a mild roister, real sailors use sials as they work, all this isak newton shit is just laughable, laughable on a stable flat clam sea, mind you yul get a good earth for the lightinening if you lick the tether and wear rubber boots :) lol good luck..........
That's working with your planet! Keep up the good work!
In just a few minutes one can understand the simplicity of sailboat and it’s inherent advantages without even bring up its upwind sail capacity.
A sailboat isn't simplistic at all. We're just used to it. Most of all: keep in mind that in this example the additional kitesail is nothing but a little optional gimmick for some extra power, on top of its main propulsion system. This is first and foremost a SOLAR boat (and the fist boat to have completed a circumnavigation under sun power alone) - and yes, by nature it can point as high to the wind as you want and is 10times more simplistic than a sailboat. What drives maintenance and costs up in a sailboat? Basically everything that has moving parts and/or is exposed to the elements. Sailing vessels have A LOT of that. Sails, including multiple sailplans, running + standing rigging, Diesel engine, winches... On the other hand: solar panels, charge controllers and brushless electric motors are highly reliable and almost maintenance-free. In other words: the solar(!) vessel is the part with the real merits, at least as long as the overall vessel is light enough (and in this regard, i.e. when you look at displacement per solar peak power, many other solar boats are actually doing better than the PlanetSolar Turanor). I admit that solar vessels don't work when you need to carry a lot of cargo, but for simple cruisers (e.g. have a look at the Sun Concept 12.0 Cruise!), they actually make more sense than sailboats which are motoring or motorsailing half of the time anyways because the wind isn't in their favor.
@@___Chris___ Trimarans and performance cruising catamarans seem to solve that "wind isn't in their favor"-part...
It wasn’t moving or am I wrong
you are wrong
That boat isn’t going fast at all. I suppose they’re testing out the theory and scale up. I could see that, potentially, the kite cold be much bigger than any sail. Can it tack?
Yes, however the tack angle is 179deg. If the whole world is an ocean then they are set! Perhaps this is an ad for more ocean and less land.
Jk, can't knock innovators for trying!
Of course kites can tack, ask any kitesurfer. Perhaps not 45 degrees off the wind, but 60-70 is certainly possible. But even leaving that aside, this makes one badass spinnaker. Bow kite designs have a huge wind range, you could essentially make it self-reefing.
Large freighters will all use enormous kites in the coming years. Reduction in fuel costs, greater efficiency and lower emissions mean they will be upscaled. Wing sails are already appearing on cargo ships, kites have even more potential.
Yes, it looks cool, but there's a reason our ancestors didn't use kites to cross the oceans. It's the surface area of the sail that gives the power and that kite is like trying to pull a train with a horse and carriage.
Fantastic! They got it to work😁
Not from what I saw.
Sounds like sailing with more steps
less steps though. you have almost no care of wind direction and its fully automated.
no rigging, lines, or tacking. sounds like less steps to me
Looks like a lot of work.
Its a great idea. No power use at all
not sure what they trying to achieve, but Captain Sparrow was sailing long time ago using sea shells on dry land ..arrrrr
Now let’s see it go UPWIND 🤓🤓🤓
Amazing 🤩
You know it's crap when they put up figures but leave out the distance travelled,
Ah let's try mast, boom, stays, sheets...... actual control.
AHRRRR
Would be great start if they stopped the kite from rolling left and right to reduce the loss of power and direction.
I think the idea is to increase the apparent wind speed over the foil, and therefore the lift. Same way a kitesurfer finds speed
Simply awesome.
Uhhhhhhhh...maybe because they were too busy looking up flying the “kite” but did they realize that they weren’t moving? Was the kite generating energy to be stored for propulsion later? I can’t imagine that kite would be ideal for physically pulling the boat in anything but flat water on sunny perfectly windy days??
By your reasoning a sail on a mast wouldn't be ideal for physically pulling a boat in anything but flat water either... more dangerous actually as the heeling moment is much larger.
What does Nds stand for? 1:10
Kingjeffkoch
Not doing shit!
curtismayne1 haaaaaaaaaa Lol gold , yeah didn’t look like it was doing much , was a big boat though . Be interesting to see it on a 30 footer
Genius. Pioneers. Leaders. (102 sheep.)
top speed 9.8 Nds what does Nds stand for? is Nds better than knots, kilometers per hour. miles per hour?
knots in French
@@LuigiSimoncini Grazie!
It would be nice to know the wind angles it can be used
Also the min and max wind speed it's safe to fly.
depends on the kite and hull. sailing kites is awesome. its all about apparent wind.
Wow these guys are really good at wasting money
@Woobie I love sarcasm!!Brillant!I was thinking of the whalers from Nantucket when I read your words.LOL
It said automated pilot. Is that only for the rudder or does it include flight control?
Was the boat suppose to move at some point? Did I miss something?
Wow amazing...
Is it more efficient than a regular sail
Saw 9 knots indicated somewhere! It looked like the yacht was standing still!
But why does it have a nonstop flight time?
What unit is nds, knots?
I had this idea when was 9 years old and that was a long long time ago now.
maybe it should be used to charge the ship battery during the day while solar panel power the propeler. so during the night the battery is full and can be used or just keep the kite to powerup powur the motor.
What is the advantage?
It looks logical but is it practical? Of course, practicality is what you are trying to build into it!
Why is the flight time only limited to 9 hours?
Green energy+ blue heart 💙
this is it man kind not priorities
Wind 💨 🌬 headmost leading✅👍🐚
Imagine fouling those lines in a near Hurricane conditions, 😜
Nah you leave them out and boom you got yourself a big ass paraglider
You hit 35 knots haha
@@clouclouc
Haha 😄
If you are out in a small boat in hurricane conditions then your parasail is the LEAST of your worries.
You have to CHECK every single second.. harder than sailing and just some benefits...
Herd of sea turtles would pull it faster.
The kite needs to be at least 5 times that size. For a hull that big.
This craft has "huge" solar panels - they even extend, and a computer-designed hull, yet generates a maximum of 165 HORSEPOWER under IDEAL conditions giving a 5.5 MPH top speed (unassisted by the battery reserve, which is needed to run systems at night) This is roughly like putting a MEDIUM SIZE jet-ski engine on board to "Propulse" a many ton Yacht.
What the sail adds is prolly barely noticeable, but it would be at least SOME thrust at night.
For y'all stuck in the Metric system.....123KW.....8.85kph.....
Good idea but boats too big for the wing and they are not controlling the attitude or altitude of the wing.
Looks like a waste of time to me .
How can 1 line pull a boat that big & make progress the Ariel shot of the little boat passing on the right now thats progress
I'm really puzzled as to why would anyone show this vid & think it'll catch on DOH !!!!
I prefer my sailboat ~6kts , max speed 11,7kts (with 35kts wind) Why not use a big sailboat like a ocean liner for passenger transport ?
needs a box kite trial. or a really large standard triangular kite. i built a 15 foot triangular kite. it lifted off extremely stable. i did not have the line for it. it sat on the side of 330 pelton. scrz
Seems Seeing solar ship sun supply stops short so sinceforth suppling
Support some sorta sail sent soaring
Can you do it? Sure.
Would that be practical especially for short handed sailing? I doubt that.
Be very careful that thing doesn't hit the water and you run over it. I'm assuming there is a rudder and a propeller from your solar electric motors. That could be very dangerous if things go wrong.
you know, sails work a sheet load better
Any reason one can't rig a 42' or 52' sail boat with this sail on front to give more speed? Love it. I guess I love the technology just as much as the added speed going across oceans.
Why would you ? A spinnaker is more efficient as it has a larger sail area and is directly coupled to the boat which means it would be more efficient.
You can ... Theres a chap who rigged a round chute to his yatch off a stub mast ..
@@pentachronic
Actually a kite sail flying in a figure of 8 is many times more powerful for a given area and because it can fly above the turbulent surface layer the wind speed is more constant and is higher generally.
@@clivestainlesssteelwomble7665 Ok, I stand corrected, but I don't understand why it would be. From my understanding of physics on a kite vs a spinnaker you have a smaller surface area, even if the wind is faster due to being above the ground attraction, the PSI will still not outstrip a larger sail area. Please show me the math/physics as I'm intrigued.
@@pentachronic
The power is generated because the kite formes a 3dimensional aerofoil with the tube Spar forming the leading edge, the other contributing factor is the speed of the kite flying in its figure of 8 pattern the angle of the wing is akin to the pitch and speed of a propeller in the air rather than a passive primitive hang gliders wing. There are also Ram air kites..
As for the numbers i will try to find you some links ... the largest kite systems have been deployed on cargo ships.
At large size they do have limits like tacking into the wind but the figures are on a par with some poor conventional sailing vessels.
The other is if you are faced with weak intermittent winds ...
You do have the option of going higher though to find more consistent airs. When it drops completely you have to haul it back in at the moment ..a stub mast can keep it ready above the fore deck in a calm but ..I suggested a larger kite with helium ballonets to provide enough bouyancy to support the kite and its harness on pehapse a minimal length of line till it picks up.
czcams.com/video/yLDb9w6X9eo/video.html
Theres a basic area traction force diag.
czcams.com/video/DwiXTye681M/video.html
This is a performance foiling kite boat near 37 kts czcams.com/video/qrkrepYd_uI/video.html
A kite boat hull... Tacking... Moving up and down wind.
czcams.com/video/64J0-etds5E/video.html
Brief History.. czcams.com/video/LpQb0PZx2BA/video.html
New Atlantic record
czcams.com/video/deq-opacVUM/video.html
This guy might be able to give you the numbers Sam Light czcams.com/video/Idd9ATteoWM/video.html
Фантастика 👏👏👏👍
Isn't the kite shedding power with all its looping back and forth crazily? What is the engineering reason for that motion, rather than taming it to pull steadily in one position?
apparent wind
would like to see this in a stormy sea..................................
Stuart Brown Lol right? There’s no reefing on that is there!
I bet you’d just have to pull it in when that weather was coming.
How big is kite surfese m2 and how much dos the boat weight kg?
amazing idea for our future!!! thanks ❤️
Admirável mundo novo!
Fantástic!
why not having sails instead ?
I don’t get it.. how tidi you steer / control it
Wouldn't it be better to have it down lower?,i mean normal sails that inflate can pick up more air ,with the kite pulling up,there is zero to hardly any forward momentum by the looks,apologies in advance if it appears i don't know what i'm talking about,i'll go back to my beer now,carry on. ;-)
Fantastic! !
how is up wind or close reach?
How well does it work without a computer?
The kite is going in all directions so effectively reducing the speed and we can see from the video that the boat is hardly moving (if at all) so it is good to test a concept but I don't think it is better than the proven technology of the sails.
It's not meant to replace sails, only to improve the speed by a few % while not having to steer it
@@Aeradill Too much junk and equipment for only a few percent. Even with that a frame thing you could have rigged a couple of sails wing and wing and got a lot more power for lots less money using simple gear. As a test of concept, OK. In practice, FAIL.
@@kolsen6330 You'll be blocking the sunlight, in effect lowering the power from the panels. By that point you might as well build a sailing cat as it is much faster than this. in wind speeds ranging from 3-6 knts a kite like this will get you another knot or two. And going, say, on a transatlantic with the trade winds not changing for days, that 1-2 knots will amount to substantial less travel time in the end.
Yes it has specific uses. it's not meant to replace sailing but rather offer alternative travelling methods while, as you mentioned, also having this concept tested out to perhaps iterate upon.
Interesting test - the figure 8 pattern seems unnecessary waste of power but I am sure someone has put a lot of thought into this - definitely keep experimenting and trying this in more variations
The figure 8 generates *more* power, as any kitesurfer can tell you. Think of it this way: the lift of an airfoil is proportional to its airspeed. If the kite travels 5x as much as the boat due to the figure 8 patttern, then its average airspeed is 5x the boat speed, hence 5x the power.
It's the most efficient way known today, try kite surf and you'll see for yourself.
How fast is a Nds? What does that even mean?
It’s not Kts (knots aka nautical miles per hour)
It’s not kmph
It’s not mph
It’s not mps
It’s not fps
It’s not anything google recognizes
It’s not even that weird way to abbreviate knots (kn) yuck
So what is it?
Non Defined Speed?
noeuds is knots in french
Feeling like watching WATERWORLD now
WTF is propulsing? Do you mean propelling?
This PULLS the boat where sails push the boat , correct?
Very cool! You meant "propelling," right?
why can it only fly 9.5 hours? What happens if you go over?
OH! Go fly a kite!
M-Kay.
This is amazing, but I have to ask, why such a small kite, a spinacle would have almost same size, the fact you go high means you could have bigger sails then regular ! Also, if you put Hydrofoil under your boat so it got no drag while it is lifted by the sea while being lifted by the kites.
Cost effectiveness
does it go only downwind? also sidewind? or also upwind?
Action against the keel(s) should be able to go a little into the wind
On aimerais voir la navigation avec kite contre le vent, c'est ce qui est le plus intéressant. En principe ça marche mais on aimerait le voir.
How do you know when to bring it down without it falling in the water?
...propulling???
LOL!
Has anybody attempted ocean crossing with skysails ?