Is this new foil asymmetrical? Short answer: no Long answer: it looks asymmetrical as the images I have offered up to the rule box are not always perfectly square. I try to play with the tilt and pan of the images to present the best representation, but this also increase distortion in other ways. There is a small possibility of asymmetry which I cannot rule out, but I personally believe it's just a side effect of the image manipulation. 👌
I understand they can only have three foils in the cup, and they have to be the same design. Assuming one is a spare and may have to fitted on either port or starboard if used, that basically rules out using asymmetrical foils
Worth beating in mind they’re still validating their design tools, this “backwards step” may just be them testing the extremes of their cfd program to make sure any extreme designs they’re working on are going to give them the benefits the design team think they will team nzl have proven to be able to work at the cutting edge, I’d be very surprised if they dropped the ball on something as critical as foil design
Potentially - ETNZ may be looking at a partial span flap. There the chord is fatest/biggist, that would have a big flap, with a big deflection, to aid in 'starting' (getting foil-bourne at low speeds). The outbound section of the foil wouldn't have any flap, and is a much narrower chord, and that section is much more optimised for high speed/low drag. That could also aid with tip vortex drag losses.
Another aspect I wonder about is the difference between dynamics at speed. With aircraft at slower speed things are rounded... higher speed they often get harsher edges, and not just for stealth reasons.
Not sure that the wind speed in Barcelona in October is playing a role here (it can also blow quite hard!), one always wants the greatest lift versus minimum drag, and you can control the speed input via the sails. Perhaps what they are thinking about is how they are able to control the 'control surfaces' on a low drag wing. But to be honest one would have to be in their design office to understand their thinking!
Yes, there does appear to be more curvature on the right but it's slight if it's there. I don't fully understand the rationale behind asymmetrical foil design to tell you the truth. Specifically, the Alinghi new tubercle foil. I'm no foil or wing expert but why not apply the tubercle design across the whole foil?
I think the difference is just in photo distortion. The race foil will have to ultimately be symmetrical, that's a class rule. So any asymmetry is purely for testing purposes.
Thank you! Always fascinated by what the teams are up to. And when we can’t make sense of something it seems also likely that they’re ahead of us in their thinking. That makes each change all the more tantalising. Good luck next week!! 💨💨🌊🌊🇬🇧🇬🇧
I would say that building it for the opposite side to the banana is wise. They can now test it against the 1 design for a base, and then against the banana next.
looking at available weather statistics, the average wind speeds and gusts in October are higher than the previous months. Overall however, there is a high probability of only a light breeze. Is ETNZ therefore focusing on a foil that promotes early lift off versus ultimate speed? As we saw in the last Cup cycle, staying on the foil versus floating around can make a huge difference in a very short time.
I think you’ve nailed it on the foil aspect ratio being related to the time of year. Team NZ have been very clever to write rules that have given them a huge advantage by designing a foil for just one set of conditions while the challengers can only run one design of foil for two very different set of conditions. Unfortunately, it could be another runaway win for Team NZ who have optimised foils for lower wind conditions only. I can picture the final having one boat that can only ‘fly’ in say 8 knots of breeze while Team NZ can get up and ‘fly’ in 6 knots which means it could end up as yet another final whitewash. I sincerely hope the wind conditions are unseasonal and give Team NZ a real challenge unlike the last very one sided final.
Detail and analysis is fascinating, and honestly is beyond me now. If we are down to the last and looks like the 1 percentage that makes the difference to winning the Americas cup, whats happening above the water line and who has the best crew driving these boats?
1) What do you call the flaps on the trailing edges of the main lifting foils? I believe on airplanes they are called ailerons. And the flaps on the aft or rudder wings on airplanes are called elevators. 2) Do the AC foils have elevators on their rudder foils? TIA
Regarding the square tips, maybe the clue is in the rule that foils may be modified by 20%. Perhaps ETNZ will be fairing the tips to a more aerodynamic shape after recording performance with the square tips. Regarding the fairing around the bulb. I believe the accepted wisdom is just not to fair or blend the joint. It is best to just leave it as a tight corner. Any blending is just lost aerodynamic wing area and thus increased parasitic drag.
Do you have any information that can help us understand foil thickness or volume? It seems that everyone is near max span, and area is pretty clear, but the other variables are really important as well!
Good luck in Garda! The foil planform is largely elliptical, which is potentially the most efficient shape. Lower A.R. means lower pitch sensitivity. Having a more discrete bulb suggests that a blended form doesn't give much benefit, maybe we'll see a trend in the foils used by the other teams.
The ETNZ new foils look stiffer to my eye, more in the cord dimension. Perhaps the aspect ratio of the older foils produced a minor flutter which adversely affected the control surfaces.
I think we're also seeing in other foil sports a balancing of aspect ratio IMO leading to an overall faster package at more points of sailing and in rougher sea conditions. Perhaps this is what TNZ is thinking?
I would assume that they probably do most of their comparison on their sims. If the sims are accurate enough and their data collections are also accurate then they won't need to race compare them at this stage.
Possibly TeamNZ has a bit less money than they had planned for. The government decided not to help fund them this time and sponsorship was a bit thin through covid times. They may not be able to do all the things they had hoped/planned. With the new foil the pronounced bulb edge was interesting. It lets them have a more effect wing section near the root, although interference drag would possibly be higher.
@@Mrlang74 haha there is fine and there is flush. They are just fine. They did buy 10 boats but those boats cost less than a foil control system. Indeed about a years salary for an athlete. I think we are talking about 1 million in boats for the youth league. And that's assuming retail pricing for a charity buying multiple hulls from a prestigious team. But bloody good on them, I see the young guys out in the harbour all the time and that's the next generation of athletes out there.
Can anyone explain how a curved flap fixed to a curved foil can hold its curve while flexing through its range .Down deflection requires that the trailing edge becomes shorter while upward deflection means the trailing edge becomes longer if the foil itself remains at a constant curve.
Can you do a video on how they are rotating the rigs with multiple hard points and spreaders? It's breaking my brain, definitely not a standard rotating rig with diamonds and one set of shrouds
Its not able to building at a foils different shapes from inner to outside flap ? How many they able to building on testboats? And how many they able building for AC boat, chooses one before race?
The race foil have to be symmetrical about the arm. They are allowed four test boat foils. For the AC75 race boat they can build 3, but they all have to have the same design (but can be modified by 20%). One they have their three AC75 foils they can choose which to race with when.
What is the density variance? I've never thought of that.. Mind you, is suspect the water temperature would make a bigger difference than salinity. (Very small numbers either way, but numbers all the same)..
@@derekstannett8477 Rocket Lab only care about aerodynamics for -- at most -- between 60 and 80 seconds after liftoff. Maybe less: from 65 to 75 seconds.
Could it be that this design is intended to be as vanilla possible so that it can work as a gold standard to test against? I presume it's really difficult to make comparisons between foils when so many variables are at play.
This is their first bulbed foil to date. It may be that they’re after some experimental confirmation of whether they had left anything on the table by avoiding bulbs. But considering the minimal allotment and long lead time we should expect that all teams have multiple test aims for each foil design they build and launch.
It got me thinking about the Ukraine war and the debate over depleted uranium, it is much more dense than lead. The bulb on the foil is smaller but probably the same weight. Do they have a new material in there.
@@losvedese78 I think the wording is something like: "no structural materials shall be of a density greater than" at least that was the case in the prior class rule.
A few people have commented the same. I think it's distortion from the photo's not being completely square. I try to correct as much as possible in the imaging editing but it's not perfect
How much are you scaling each foil to fit in the AC75 Box? What's the weight&volume of each foil compared to a AC75 foil. What's the weight of each leq12? How are the teams going to scale these designs, could they use the same effective bulb and transition and increase the wingspan or does everything need to scale up xyz ... so many variables.
I have scaled these so that their span matches the AC75 rule. So it assumes all teams will / are basing their design on maximum foil span. That was certainly a pretty good assumption in the last cup, but until they launch their race boats next year we won't know for sure
@@MozzySails if a team can run a full sized AC75 bulb and cord length "center section" on an leq12 so all they have to do is extend wingspan later I would assume they would be getting more "realworld" data then a team that will Need to increase cord and blub volume when building an AC75 foil
Yesterday ETNZ mentioned that they had a new high speed of 57 knots on day one of using that new foil. So yeah I don't think that they need to worry about their speed. 😶
well, they mentioned that. There's no reason to believe either way. It's an incredible speed. Must mean that one design AC40 rudder is pretty capable too...
Looking at the Alinghi video today I would guess there must be a huge amount of thinking going into how to handle lumpier conditions as we know how damaging dropping off foils is to overall result. 57 though is amazing even if just briefly.
Hi! Your videos are often very different interesting thank you. But they’re also generally too long, you could clearly focus more, or edit more. I know i would watch them more if you concentrated them. Or you could have two versions, à focused 3min w the key bits, and a 10-15min for people with time to kill 😉 thanks!
I understand what you're saying and will look to try more 'headlines only' videos. The flip side is I think a lot of people come to my videos for more discussion, and so the reasoning to why I think X or Y helps when they join the conversation in the comments below
Is this new foil asymmetrical? Short answer: no
Long answer: it looks asymmetrical as the images I have offered up to the rule box are not always perfectly square. I try to play with the tilt and pan of the images to present the best representation, but this also increase distortion in other ways. There is a small possibility of asymmetry which I cannot rule out, but I personally believe it's just a side effect of the image manipulation. 👌
I understand they can only have three foils in the cup, and they have to be the same design. Assuming one is a spare and may have to fitted on either port or starboard if used, that basically rules out using asymmetrical foils
Worth beating in mind they’re still validating their design tools, this “backwards step” may just be them testing the extremes of their cfd program to make sure any extreme designs they’re working on are going to give them the benefits the design team think they will team nzl have proven to be able to work at the cutting edge, I’d be very surprised if they dropped the ball on something as critical as foil design
Potentially - ETNZ may be looking at a partial span flap. There the chord is fatest/biggist, that would have a big flap, with a big deflection, to aid in 'starting' (getting foil-bourne at low speeds). The outbound section of the foil wouldn't have any flap, and is a much narrower chord, and that section is much more optimised for high speed/low drag. That could also aid with tip vortex drag losses.
Another aspect I wonder about is the difference between dynamics at speed. With aircraft at slower speed things are rounded... higher speed they often get harsher edges, and not just for stealth reasons.
Need to get Rob and Tom back in for a chat with you
I've been trying... Trust me! Life and work commitments make side project like RUclips difficult
Great reporting. Looking forward to the next video on the new INEOS and radical Alinghi foils. Godspeed in Garda!
Not sure that the wind speed in Barcelona in October is playing a role here (it can also blow quite hard!), one always wants the greatest lift versus minimum drag, and you can control the speed input via the sails. Perhaps what they are thinking about is how they are able to control the 'control surfaces' on a low drag wing. But to be honest one would have to be in their design office to understand their thinking!
Great video as usual. Thanks for all the effort you put in! 👍
Good luck in the competition and thanks for the content. All good.
Thanks!
Cool video and analysis. Yes, October must surely be a factor. Best wishes for Garda!
Thanks for the foil update. All the best for Garda, Tom.
The new wing seems asymmetrical, more pronounced curve on the right, at least against the image grid.
Yes, there does appear to be more curvature on the right but it's slight if it's there. I don't fully understand the rationale behind asymmetrical foil design to tell you the truth. Specifically, the Alinghi new tubercle foil. I'm no foil or wing expert but why not apply the tubercle design across the whole foil?
I think the difference is just in photo distortion. The race foil will have to ultimately be symmetrical, that's a class rule. So any asymmetry is purely for testing purposes.
Would be good to see that rule change
Thank you! Always fascinated by what the teams are up to. And when we can’t make sense of something it seems also likely that they’re ahead of us in their thinking. That makes each change all the more tantalising. Good luck next week!! 💨💨🌊🌊🇬🇧🇬🇧
I would say that building it for the opposite side to the banana is wise. They can now test it against the 1 design for a base, and then against the banana next.
looking at available weather statistics, the average wind speeds and gusts in October are higher than the previous months. Overall however, there is a high probability of only a light breeze. Is ETNZ therefore focusing on a foil that promotes early lift off versus ultimate speed? As we saw in the last Cup cycle, staying on the foil versus floating around can make a huge difference in a very short time.
I think you’ve nailed it on the foil aspect ratio being related to the time of year. Team NZ have been very clever to write rules that have given them a huge advantage by designing a foil for just one set of conditions while the challengers can only run one design of foil for two very different set of conditions.
Unfortunately, it could be another runaway win for Team NZ who have optimised foils for lower wind conditions only. I can picture the final having one boat that can only ‘fly’ in say 8 knots of breeze while Team NZ can get up and ‘fly’ in 6 knots which means it could end up as yet another final whitewash.
I sincerely hope the wind conditions are unseasonal and give Team NZ a real challenge unlike the last very one sided final.
This is a red herring for the challenges to be bedazzled. Given the new Kiwi boat will be a glider, not a boat then you would only need small foils
Detail and analysis is fascinating, and honestly is beyond me now.
If we are down to the last and looks like the 1 percentage that makes the difference to winning the Americas cup, whats happening above the water line and who has the best crew driving these boats?
Plenty to think about.. thanks Mozzy.. good luck in Garda
There has to be limits to small size and lift coefficients.
Cavitation still has to be questioned and smaller may have its limits there too.
very true, and what we can't see in these foils, despite the excellent recon photos, is the section shapes and surface features
Mozzy, thanks for the excellent videos. Don't forget cavitation! Particularly high speed. This explains some of what you mentioned. Thanks again
Thanks for commenting. I'm a big admirer of your work!
@@MozzySails good luck in Garda. I'll be there in 1 month...
1) What do you call the flaps on the trailing edges of the main lifting foils? I believe on airplanes they are called ailerons. And the flaps on the aft or rudder wings on airplanes are called elevators. 2) Do the AC foils have elevators on their rudder foils? TIA
Good luck in Garda- We loved sailing there.
Regarding the square tips, maybe the clue is in the rule that foils may be modified by 20%. Perhaps ETNZ will be fairing the tips to a more aerodynamic shape after recording performance with the square tips.
Regarding the fairing around the bulb. I believe the accepted wisdom is just not to fair or blend the joint. It is best to just leave it as a tight corner. Any blending is just lost aerodynamic wing area and thus increased parasitic drag.
Yes its ALL interesting to me and Goodluck with your Sailing this weekend
Enjoy Garda, one of the best sailing venues I have seen!!
Just hoping the weather improves. Italy has had a lot of rain recently!
New Zealand is the innovator and never shows all its cards leaving the rest of the field scratching their heads guessing.
Do you have any information that can help us understand foil thickness or volume? It seems that everyone is near max span, and area is pretty clear, but the other variables are really important as well!
Fantastic insight. Best of luck at Lake Garda!
Good luck in Garda! The foil planform is largely elliptical, which is potentially the most efficient shape. Lower A.R. means lower pitch sensitivity. Having a more discrete bulb suggests that a blended form doesn't give much benefit, maybe we'll see a trend in the foils used by the other teams.
The ETNZ new foils look stiffer to my eye, more in the cord dimension. Perhaps the aspect ratio of the older foils produced a minor flutter which adversely affected the control surfaces.
Best of luck at Garda 👏👏👍👍
I think we're also seeing in other foil sports a balancing of aspect ratio IMO leading to an overall faster package at more points of sailing and in rougher sea conditions. Perhaps this is what TNZ is thinking?
I would assume that they probably do most of their comparison on their sims. If the sims are accurate enough and their data collections are also accurate then they won't need to race compare them at this stage.
Possibly TeamNZ has a bit less money than they had planned for. The government decided not to help fund them this time and sponsorship was a bit thin through covid times. They may not be able to do all the things they had hoped/planned. With the new foil the pronounced bulb edge was interesting. It lets them have a more effect wing section near the root, although interference drag would possibly be higher.
They are fine didn’t they just buy ten boats for the rnzyc
@@Mrlang74 haha there is fine and there is flush. They are just fine. They did buy 10 boats but those boats cost less than a foil control system. Indeed about a years salary for an athlete. I think we are talking about 1 million in boats for the youth league. And that's assuming retail pricing for a charity buying multiple hulls from a prestigious team. But bloody good on them, I see the young guys out in the harbour all the time and that's the next generation of athletes out there.
Does one side look flatter than the other? is it designed for one side of the boat only?
Can anyone explain how a curved flap fixed to a curved foil can hold its curve while flexing through its range .Down deflection requires that the trailing edge becomes shorter while upward deflection means the trailing edge becomes longer if the foil itself remains at a constant curve.
Good luck in the RS racing!!
Is that asymmetrical? Might make sense for keeping the tip from breaking the surface.
Hi. Do you have any idea where LRPP Ac40 is? They are still working on their LEQ12
They have received it. I can’t remember if they sailed more than one day though.
They recieved it a while ago, bit have only done a week or so.sailing on it ruclips.net/video/lRLSSan8w_Q/видео.html
Can you do a video on how they are rotating the rigs with multiple hard points and spreaders? It's breaking my brain, definitely not a standard rotating rig with diamonds and one set of shrouds
Its not able to building at a foils different shapes from inner to outside flap ?
How many they able to building on testboats?
And how many they able building for AC boat, chooses one before race?
The race foil have to be symmetrical about the arm.
They are allowed four test boat foils.
For the AC75 race boat they can build 3, but they all have to have the same design (but can be modified by 20%).
One they have their three AC75 foils they can choose which to race with when.
The curvature looks asymmetric, is that true and or legal. Or is it just a photo illusion?
the photo's are a 'best fit'. There is always some distortion due to the shots not being square on
I wonder if they ever take consideration the different water density in another part of the globe when it comes to design?
What is the density variance? I've never thought of that..
Mind you, is suspect the water temperature would make a bigger difference than salinity. (Very small numbers either way, but numbers all the same)..
All the best for the Euros !
Sometimes less is more.
Is NZL using any kind of aerospace or F1 support to design/develop/analyze their foils?
AFAIK the only f1 partnerships this cup are ineos/mercedes and alingi/redbull
Maybe they are using Rocket Lab, they're only just up the road and the Kiwis are quick 😊
@@derekstannett8477 Rocket Lab only care about aerodynamics for -- at most -- between 60 and 80 seconds after liftoff. Maybe less: from 65 to 75 seconds.
Good luck in Italy!
Thanks!
Could it be that this design is intended to be as vanilla possible so that it can work as a gold standard to test against? I presume it's really difficult to make comparisons between foils when so many variables are at play.
You would think the one design would be the vanilla option.
This is their first bulbed foil to date. It may be that they’re after some experimental confirmation of whether they had left anything on the table by avoiding bulbs. But considering the minimal allotment and long lead time we should expect that all teams have multiple test aims for each foil design they build and launch.
Good luck for Garda
Cheers Claire!
It got me thinking about the Ukraine war and the debate over depleted uranium, it is much more dense than lead. The bulb on the foil is smaller but probably the same weight. Do they have a new material in there.
Part of the rules for the foils is that they can’t have a density greater than lead. So no tungsten or DU ballast this time.
^this
@@weatheranddarkness Does the rule refer to the 'foil density' or the density of materials used in the foil, that could make some difference
@@losvedese78 I think the wording is something like: "no structural materials shall be of a density greater than" at least that was the case in the prior class rule.
keep thinking that, we'll show otherwise.
enjoy Garda!
thanks!
HA HA reporting from New Zealand GB will always be 12 hours behind
Additionally, planning for weather a year from now in this era of climate change, must have meteorologists sweating.
I bet you climate change so called makes no difference other then in your imagination.
Enjoy garda!
thanks! Fingers crossed for some good weather and fair breeze!
Each side looks different from the centre line
A few people have commented the same. I think it's distortion from the photo's not being completely square. I try to correct as much as possible in the imaging editing but it's not perfect
But "anhedral foil" sounds better than "banana foil" 😂😂
that is true!
How much are you scaling each foil to fit in the AC75 Box? What's the weight&volume of each foil compared to a AC75 foil. What's the weight of each leq12? How are the teams going to scale these designs, could they use the same effective bulb and transition and increase the wingspan or does everything need to scale up xyz ... so many variables.
I have scaled these so that their span matches the AC75 rule. So it assumes all teams will / are basing their design on maximum foil span. That was certainly a pretty good assumption in the last cup, but until they launch their race boats next year we won't know for sure
@@MozzySails if a team can run a full sized AC75 bulb and cord length "center section" on an leq12 so all they have to do is extend wingspan later I would assume they would be getting more "realworld" data then a team that will Need to increase cord and blub volume when building an AC75 foil
Yesterday ETNZ mentioned that they had a new high speed of 57 knots on day one of using that new foil. So yeah I don't think that they need to worry about their speed. 😶
well, they mentioned that. There's no reason to believe either way. It's an incredible speed. Must mean that one design AC40 rudder is pretty capable too...
Looking at the Alinghi video today I would guess there must be a huge amount of thinking going into how to handle lumpier conditions as we know how damaging dropping off foils is to overall result. 57 though is amazing even if just briefly.
What do you call the polar opposite of sandbagging?
Disingenubragging?
The commentator in F1 is fond of saying “flattered to deceive” particularly when comparing apparent pace on test days versus race days.
This was subsequently corrected to 50.7 knots. Which is still impressive, bit more plausible
Lol they just went 56 knots... ok
No they didn't, it was a misspeak by Blair, corrected to 50.7knots later. Which is still impressive.
@@MozzySails "misspeak"? There's a Tui beer saying here in NZ. "Na.. yeah right!"
I see something else....
To much thinking bro
Hi! Your videos are often very different interesting thank you. But they’re also generally too long, you could clearly focus more, or edit more. I know i would watch them more if you concentrated them. Or you could have two versions, à focused 3min w the key bits, and a 10-15min for people with time to kill 😉 thanks!
I understand what you're saying and will look to try more 'headlines only' videos. The flip side is I think a lot of people come to my videos for more discussion, and so the reasoning to why I think X or Y helps when they join the conversation in the comments below