Competition hang gliders have been using twin skin soft surface wings for a number of years now. Glad to see the idea is catching on in the high performance sailing world.
Fascinating wing tip engineering ....This brings me back to the original "winged" keel breakthrough when Australia won the cup...Like to see how these racing machines perform in ultra - light breeze
@@davidho2977 they have a minimum amount of wind approximately 6 knots and a maximum of approximately 20 knots. Reason for these limits feels so that they are finished within 45 minutes or it is terminated. So they don't sit out there all day doing nothing. Also sailboat races have a time limit for the same reason. The maximum wind is set so that the boats aren't broken to pieces.
so does the rear foil act as a down force to keep to boat from sinking forward? or does the mid section foil just produce so much more upforce that it causes the front to lift?
I wonder what would happen if they just said “you know what? Go crazy. See what kind of crazy sci-fi stuff you can come up with. Everything is allowed besides completely going out of the water.”
Allowing the windward foil to be in the water would allow teams to generate additional righting moment and hence more power - arguably too much that would create serious structural issues. The other reason is that the defenders in any cup cycle want to be able to to limit the amount of righting moment and hence know the max power of all of the challengers. Creating rules that place a cap on righting moment by preventing the use of a foil that pulls down on the windward side one way of doing this and easy to police
5:15 It appears the animation has the pitch the trailing edge opposite of the movement of the wing and is shown incorrectly. When the trailing edge flap goes up the wing should go up when the trailing edge flap goes down the wind should go down. At least it does in aircraft maybe it’s the opposite with this underwater wind for some reason
The animation is correct. Pitching the flaps down increases the camber of the foil which results in a higher lift force to raise the boat out of the water. Think of flaps used for takeoff and landing in an aircraft, they are used to increase lift at lower flight speeds.
@@jackdavies5784 agreed, but then I’m curious, how do you control the global pitch of the vessel? Done topside, somehow? Edit: oh I think I’ve got it; the horizontal control surfaces of the rudder could act to control vessel pitch
It’s not a rule. Quote often they use both. But in general, at high speed, when foil lift comes over and the boat actually flies, the wind torque can be balanced only by one foil in the water. If there are two foils in the water you have not the force equilibrium. It’s a very simple engineering exercise.
The boats look like they are pretty stable when they're up on the foils. I thought maybe they would want to have the windward foil still in the water and angled to produce downforce.
That would increase drag. They are stable without having both foils in the water and if you watch the first few runs, the teams already look pretty confident with their boats already.
As I drive around my Tesla, or rather as it does a lot of the 'driving,' sometimes I think about sail boats. How soon will there be blue water sailing cruisers with foils? I'm sure someone must be already sketching out some ideas. Dolphin windows (please credit me for this neologism) on the hull so people in the saloon can look down and see them zipping along. I'm sure that when I see videos of sailboats I feel what Slocum feels, but when I see those foil boats that thrill is brand new.
Big foils like these don't work so well in ocean waves. Imoca 60 already have foils but they are not flying like this since the drop down would be too destructible...
@@jussimaristo8979 Yeah true. The Imoca 60 foil boats are not fully flying like this. But they do lift quite a bit of the hull out of the water much of the time from what I can tell. The aft section of the hull is almost always in the water, though.
@@andrewmitchell5807The pressure required to compress a volume of liquid water by 1% is 2 x 10^8 Pa... So basically in normal conditions is really incompressible.
What control surfaces are the AC 75 boats wings? Does the tail just have a rudder, rudder and elevator, or rudder, elevator and ailerons? Ok, ailerons. No, rudder or elevator? No elevator, these boats are going to pitch pole violently, not a very intelligent design. How do they change the lift on the stern from positive to negative to keep the nose out of the water?
@@allentobolewski7273 Thanks but please elaborate. The energy is stored in a battery? On a normal yacht, the winch is turned manually which rolls in the sail and jib at the same time. All I see is the grinders continuously grinding to no end. Surely they aren't always trimming??
@@skeche . There are two types of Grinders. one is direct drive to turn spindles for trimming the sails. The second kind is hydraulic to move the Mainsail and lift and lower the Water wings.
I have sailed, racing and cruising, many classes of boats, center board, keel and catamaran, since 1962. These America's Cup things are NOT BOATS! Just as the 3 wheelers with sails are not.
I watched a video where Team NZ said they had a comp programme they told them what was the optimal way to sail and it was up to the sailors to get there.
These machines have NO relationship to the sailing that 99% of us enjoy. These technical devices are expensive advertising gimmicks.. Monohull, cats, and multi hulls are fine but not these "flying machines". Let's see them perform in force ten conditions and the consequent rough seas!
Sailors are so conservative. It is so stupid. Has really held the state of the art back. The single skin sails with wire stays should have been left behind a decade ago or more. Anyway, the latest ocean racers are using foils and they will be in plenty rough seas for the Vendee Globe race. So we won't have to wait long to see how that works out. Mind you, I would not want to go cruising on a foil boat. But there is a lot of room for improvement in the rigs. I think it is only conservatism that has held us back.
Sailing is stupidly expensive when you consider the huge amount of capital that rarely gets used and quickly deteriorates. I sail on other people's boats rather than be guilty of the same waste. And I would oh so gladly sail on these other people's boats. Maybe one day when the price of any such technical devices drop due to them becoming more commonplace I might get a chance. The sailing that 99% of us enjoy all too often involves snobbery towards others that have spent either less or more than we have.
What a stupid comment. It's like saying F1 racing is not the driving 99% of us enjoy, I'd love to see an F1 car drive on an off road trail... they're a specific machine developed for a specific purpose. Horses for courses.
You may not be excited to see these technological marvels race for real but a lot of us are. I don't care that I'll never get to race an AC75 (although if someone wants to offer me a ride I could be persuaded) but I'm really looking forward to seeing what these boats can do and I know I'm not alone.
I am so tired of watching videos I think I am going to get a detailed look, or even a steady look and the entire video is made up of 2 second shots edited together. WTF? Fail.
