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It's pissing down outside and yes, we are back to Level 3. To all those moaning and bitching about it and calling the PM childish names, get a grip, we are the luckiest people in the world right

Yes, quite light but I didn't see all the afternoon's sailing, can only comment on later in the day, when Britannia 2 was running a #1 jib and foiling around no problem. They look quite quick at times

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9 minutes ago, Stingray~ said:

Does anyone else here think we could see more extreme versions of the Bat Wing sported in the Match? 

Interesting interview with NO and Slingsby.  Batwing discussed - their view was ETNZ were just 'ticking the box' by testing it but didn't seem to have invested much in it so didn't think we would actually see it in the match.  If it's not geoblocked then interview is here: https://www.newshub.co.nz/home/podcasts/2021/02/the-cup-podcast-what-s-got-the-aussies-cheering-for-team-nz.html

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2 minutes ago, 1eyedkiwi said:

Interesting interview with NO and Slingsby.  Batwing discussed - their view was ETNZ were just 'ticking the box' by testing it but didn't seem to have invested much in it so didn't think we would actually see it in the match.  If it's not geoblocked then interview is here: https://www.newshub.co.nz/home/podcasts/2021/02/the-cup-podcast-what-s-got-the-aussies-cheering-for-team-nz.html

Thanks for the link.. That audio is working for me.

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4 minutes ago, Stingray~ said:

Thanks for the link.. That audio is working for me.

No worries.  Certainly some interesting stuff in there - like their take on Burling... that he's more of a boat speed focused sailor.  Guess that  isn't a surprise and obviously all sailors are focused on boat speed - but it sounds like maybe his influence on ETNZ's boat speed (giving feedback and ideas to the designers) is a key factor to their success...

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19 minutes ago, 1eyedkiwi said:

No worries.  Certainly some interesting stuff in there - like their take on Burling... that he's more of a boat speed focused sailor.  Guess that  isn't a surprise and obviously all sailors are focused on boat speed - but it sounds like maybe his influence on ETNZ's boat speed (giving feedback and ideas to the designers) is a key factor to their success...

Yes, cool interview, thanks again for the link. 
 

A lot is predicated upon the idea that ETNZ will be the faster boat and so about if LR can win starts and defend their early lead. But we don’t actually know if these assumptions are correct, it could even be the other way round.. 

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3 hours ago, southseasbill said:

Wut?

B9C37028-4C6C-406E-9142-BA1839BFDEDC.jpe

 

The rumor goes this is actually NZL20 in disguise.

Remember that NZL32 was a real dog, they had to paint NZL20 black and ship it out to race?

:P

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1 hour ago, 1eyedkiwi said:

Interesting interview with NO and Slingsby.  Batwing discussed - their view was ETNZ were just 'ticking the box' by testing it but didn't seem to have invested much in it so didn't think we would actually see it in the match.  If it's not geoblocked then interview is here: https://www.newshub.co.nz/home/podcasts/2021/02/the-cup-podcast-what-s-got-the-aussies-cheering-for-team-nz.html

Cheers for the link, good interview. Then again, not sure I would like it if they were all picking LRPP 

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22 minutes ago, Stingray~ said:

Yes, cool interview, thanks again for the link. 
 

A lot is predicated upon the idea that ETNZ will be the faster boat and so about if LR can win starts and defend their early lead. But we don’t actually know if these assumptions are correct, it could even be the other way round.. 

I think there is some basis for assuming that ETNZ will be faster, but not a lot since the pre-xmas regattas were next to meaningless.

I also don't think Slingsby's assessments of Burling's starts in Bermuda was remotely correct. He absolutely smoked Jimmy in the start box although to be fair some of that was due to a more manouvreable boat (race 8 in particular).

Personally I think that the speed difference between ETNZ and LR will be VERY substantial. Far more than the difference between LR & INEOS.

I will undoubtedly get completely fucking skewered for stating that, but I will give my reasons below (not that this would stop the skewering):

 

1. They have that sexy sail that adds several square metres of area right the fuck down low where its most important.

2. They carry a significant advantage into the cup by virtue of having the most advanced wing in Bermuda.

3. They have managed to get sneaky and furtive with the rules for the foils by placing much of the mass on the foil arm faring.

4.By slimming down the foils, they leave more options for remoding because the flaps (which CAN be swapped out) form a relatively MUCH larger portion of the lifting surface, meaning they  can manipulate the level of lift/drag proportionally much more than LR can.

5. They have installed a flux capacitor in the boat (my uncle told me).

 

Let the skewering begin! Don't let me down guys! LOL!

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1 hour ago, Stingray~ said:

Yes, cool interview, thanks again for the link. 
 

A lot is predicated upon the idea that ETNZ will be the faster boat and so about if LR can win starts and defend their early lead. But we don’t actually know if these assumptions are correct, it could even be the other way round.. 

Definitely possible that LR could be quicker.  Pretty much all predictions/expectations have been wrong so far...

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I have never seen ETNZ sounding as confident about their speed as this round of the AC. I think that speaks volumes about how fast they really are, when their usual method is to downplay any potential speed advantage. Their speed is the thing they are worried least about. 

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9 minutes ago, uflux said:

I have never seen ETNZ sounding as confident about their speed as this round of the AC. I think that speaks volumes about how fast they really are, when their usual method is to downplay any potential speed advantage. Their speed is the thing they are worried least about. 

Where have you seen that uflux? I don't remember seeing anything to that effect.

Links would be wunderbar.

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2 hours ago, Stingray~ said:

Does anyone else here think we could see more extreme versions of the Bat Wing sported in the Match? 

Most likely not. The cut-outs between mainsail battens/measurement points being curved, have a higher drag coefficient than the standard leech profile. Which is not what you want in higher wind conditions.

There is a limit to reducing sail area in the leech of the mainsail versus increased trailing edge drag.

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6 minutes ago, uflux said:

I have never seen ETNZ sounding as confident about their speed as this round of the AC. I think that speaks volumes about how fast they really are, when their usual method is to downplay any potential speed advantage. Their speed is the thing they are worried least about. 

Not sure I have heard ETNZ being confident about their speed? Others are saying it but that doesn't really mean much.

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Just now, 1eyedkiwi said:

Not sure I have heard ETNZ being confident about their speed? Others are saying it but that doesn't really mean much.

Have a look at recent PB interviews.

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2 minutes ago, jaysper said:

Where have you seen that uflux? I don't remember seeing anything to that effect.

Links would be wunderbar.

Any PB interview in the last couple of weeks...Keep up :rolleyes:

He is never overt but confident.

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Just now, uflux said:

Any PB interview in the last couple of weeks...Keep up :rolleyes:

He is never overt but confident.

Sorry! Haven't seen them.

Bad dobbie! bad dobbie! :P

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2 hours ago, jaysper said:

I think there is some basis for assuming that ETNZ will be faster, but not a lot since the pre-xmas regattas were next to meaningless.

I also don't think Slingsby's assessments of Burling's starts in Bermuda was remotely correct. He absolutely smoked Jimmy in the start box although to be fair some of that was due to a more manouvreable boat (race 8 in particular).

Personally I think that the speed difference between ETNZ and LR will be VERY substantial. Far more than the difference between LR & INEOS.

I will undoubtedly get completely fucking skewered for stating that, but I will give my reasons below (not that this would stop the skewering):

 

1. They have that sexy sail that adds several square metres of area right the fuck down low where its most important.

2. They carry a significant advantage into the cup by virtue of having the most advanced wing in Bermuda.

3. They have managed to get sneaky and furtive with the rules for the foils by placing much of the mass on the foil arm faring.

4.By slimming down the foils, they leave more options for remoding because the flaps (which CAN be swapped out) form a relatively MUCH larger portion of the lifting surface, meaning they  can manipulate the level of lift/drag proportionally much more than LR can.

5. They have installed a flux capacitor in the boat (my uncle told me).

 

Let the skewering begin! Don't let me down guys! LOL!

Everything sounds true and correct!

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ACWS day three race 12.

it’s worth a watch, with hind sight it showed how good Prada were in light air

they won the start but on the first upwind leg they were consistently pointing higher than ETNZ and despite NZ being faster it 3-4 kts  just couldn’t close down the gap. tacking was just better on Prada and they just pointed higher.  Down wind Prada were again deeper And extended right until they both came off the foils. 

when The wind returned ( maybe a touch stronger?) it hit ETNZ first and they managed to stay in it overtake and pull away and ultimately take the win.  as a potential warning shot it does indicate the different philosophies in the boats and quite how good Prada could be.  Should there be a series of very light air races because if the wind hadn’t dropped completely they would’ve won by a mile 

This isn’t to stir anybody up but it was an interesting comparison and although a lot has changed since then in terms of performance the design philosophy of each team hasn’t interms  of foils if anything the gap has grown between the teams in that area
 

 

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26 minutes ago, JALhazmat said:

ACWS day three race 12.

it’s worth a watch, with hind sight it showed how good Prada were in light air

they won the start but on the first upwind leg they were consistently pointing higher than ETNZ and despite NZ being faster it 3-4 kts  just couldn’t close down the gap. tacking was just better on Prada and they just pointed higher.  Down wind Prada were again deeper And extended right until they both came off the foils. 

when The wind returned ( maybe a touch stronger?) it hit ETNZ first and they managed to stay in it overtake and pull away and ultimately take the win.  as a potential warning shot it does indicate the different philosophies in the boats and quite how good Prada could be.  Should there be a series of very light air races because if the wind hadn’t dropped completely they would’ve won by a mile 

This isn’t to stir anybody up but it was an interesting comparison and although a lot has changed since then in terms of performance the design philosophy of each team hasn’t interms  of foils if anything the gap has grown between the teams in that area
 

 

One was a boat that had little time on the water.   What was the result ? 
American Magic also looked good too I recall even beat the kiwis 

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9 minutes ago, Zeusproject said:

One was a boat that had little time on the water.   What was the result ? 
American Magic also looked good too I recall even beat the kiwis 

Yeah missing the point completely and on the offensive/defensive immediately. Brilliant. 
 

 

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4 hours ago, uflux said:

I have never seen ETNZ sounding as confident about their speed as this round of the AC. I think that speaks volumes about how fast they really are, when their usual method is to downplay any potential speed advantage. Their speed is the thing they are worried least about. 

Speed is one thing but can they point higher  into the wind and reach deeper?

Also what about tacking speed .

Spittal could win every start and then cover them and put them into a down speed tactical battle.... Or could he?

  

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3 minutes ago, JALhazmat said:

Yeah missing the point completely and on the offensive/defensive immediately. Brilliant. 
 

 

No just saying kiwis running different foils and relatively newish boat on foils half the size won by a mile . yes completely different set ups by both boats different ends of development. I’d say all racing until now is worthless viewing regarding the cup races.   Both teams will still be developing all aspects of the packages . 

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2 minutes ago, Baconator said:

Speed is one thing but can they point higher  into the wind and reach deeper?

Also what about tacking speed .

Spittal could win every start and then cover them and put them into a down speed tactical battle.... Or could he?

  

The kiwis in most racing so far have had better vmg up and downwind . If I were Luna Rossa I would be pushing to knock them off there foils restart 

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52 minutes ago, JALhazmat said:

ACWS day three race 12.

it’s worth a watch, with hind sight it showed how good Prada were in light air

they won the start but on the first upwind leg they were consistently pointing higher than ETNZ and despite NZ being faster it 3-4 kts  just couldn’t close down the gap. tacking was just better on Prada and they just pointed higher.  Down wind Prada were again deeper And extended right until they both came off the foils. 

when The wind returned ( maybe a touch stronger?) it hit ETNZ first and they managed to stay in it overtake and pull away and ultimately take the win.  as a potential warning shot it does indicate the different philosophies in the boats and quite how good Prada could be.  Should there be a series of very light air races because if the wind hadn’t dropped completely they would’ve won by a mile 

This isn’t to stir anybody up but it was an interesting comparison and although a lot has changed since then in terms of performance the design philosophy of each team hasn’t interms  of foils if anything the gap has grown between the teams in that area
 

 

I agree with your observations from that  light air race.LRPP also acknowledged ETNZ superiority in 12 knots plus and have been trying to close that gap at what expense to their light air advantage?

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5 hours ago, jaysper said:

5. They have installed a flux capacitor in the boat (my uncle told me).

Shit! Who the hell set September 19, 2013! Stop the flux capacitoooooooor

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5 minutes ago, strider470 said:

Shit! Who the hell set September 19, 2013! Stop the flux capacitoooooooor

IDK, theres a few things people could be warned about if you went back to 2013 :lol::lol:

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1 hour ago, Kiwicupfan said:

I agree with your observations from that  light air race.LRPP also acknowledged ETNZ superiority in 12 knots plus and have been trying to close that gap at what expense to their light air advantage?

Don’t Think it takes much breeze to get the small foils up and working properly and they certainly will have done a lot of work since then.  
to be honest That race was more of a sign of things to come for the Prada a cup final whether it translates to the AC final remains to be seen

What you can compare though is the up wind speeds from that first leg to the cup final light air  races.  Both teams we’re doing 30 kts up wind at higher angles than in this race so huge performance gains have been found across the board 

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9 hours ago, 45Roller said:

it was great at the time, all the black heart stuff was going on etc 

GD: Loyal (to be fair he wasn't involved then)

Also GD: eat-shit while we shop the hosting around.

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So, just caught up with this thread after a while:

ETNZ is:

- trying out AM's batwing

- experimenting with LR's dual helmsman set up

- getting back to code 0s, even using it together with the jib

 

Running out of ideas to actually make the boat faster?

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7 minutes ago, alphafb552 said:

So, just caught up with this thread after a while:

ETNZ is:

- trying out AM's batwing

- experimenting with LR's dual helmsman set up

- getting back to code 0s, even using it together with the jib

 

Running out of ideas to actually make the boat faster?

Nope just ideas and making them better and faster :D

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8 minutes ago, alphafb552 said:

So, just caught up with this thread after a while:

ETNZ is:

- trying out AM's batwing

- experimenting with LR's dual helmsman set up

- getting back to code 0s, even using it together with the jib

 

Running out of ideas to actually make the boat faster?

No, more likely best described by either Natan Outteridge or Tom Slingsby in a good recent interview: "they are ticking all the boxes".

So even if they don't think something will prove to be useful, they'll still check it out.

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1 minute ago, MaxHugen said:

No, more likely best described by either Natan Outteridge or Tom Slingsby in a good recent interview: "they are ticking all the boxes".

So even if they don't think something will prove to be useful, they'll still check it out.

I'm just surprised they think they have time to test these more or less off the wall ideas at this point in time

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Smoke and mirrors? After all the bat wing was also tried during with there "adjustable" rudder.

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10 minutes ago, alphafb552 said:

I'm just surprised they think they have time to test these more or less off the wall ideas at this point in time

I like to think of it as "leaving no stone unturned".  :)

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https://www.sail-world.com/news/235432/Playing-the-long-game

The article has an intriguing point with 62 kn being fastest reported speed by ETNZ. Was sure to find the response here somewhere with the speed being the explanation for flipping a seagull passing nearby the boat on some video. Anyone knows where this number is coming from? Pretty impressive if confirmed.

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11 minutes ago, Lakrass said:

https://www.sail-world.com/news/235432/Playing-the-long-game

The article has an intriguing point with 62 kn being fastest reported speed by ETNZ. Was sure to find the response here somewhere with the speed being the explanation for flipping a seagull passing nearby the boat on some video. Anyone knows where this number is coming from? Pretty impressive if confirmed.

It's a pity author Mark Jardine did not qualify the claim of 62 knots!

Especially as this speed should put them well into foil cavitation territory.

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4 hours ago, alphafb552 said:

So, just caught up with this thread after a while:

ETNZ is:

- trying out AM's batwing

- experimenting with LR's dual helmsman set up

- getting back to code 0s, even using it together with the jib

 

Running out of ideas to actually make the boat faster?

Well, everyone knows warp factor 10 is maximum theoretical speed and they've already done warp factor 15, so you'll pardon them if they kick back and take it a little easier.

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3 hours ago, MaxHugen said:

It's a pity author Mark Jardine did not qualify the claim of 62 knots!

Especially as this speed should put them well into foil cavitation territory.

62 knots smells like bullshit. Perhaps just Perhaps on a reach but even then.

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1 minute ago, jaysper said:

62 knots smells like bullshit. Perhaps just Perhaps on a reach but even then.

Yes, I tend towards your conclusion as well.

If it were real, it would be screeching around the entire AC circuit like a scalded cat!

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3 hours ago, MaxHugen said:

Yes, I tend towards your conclusion as well.

If it were real, it would be screeching around the entire AC circuit like a scalded cat!

Well, not really cos even if it were capable of 62 knots on a reach it doesn't say a while lot about how fast it goes up or down wind.

Artemis were generally fastest on the reach start in Bermuda but were slower on all other points of the compass than ETNZ and likely no faster than Orifice.

Which begs the question as to why would ETNZ insiders (if this is where 62 knots came from) make mention of a speed that cannot be attained in the race course?

I suspect they were all given a number to tell their mates so they leave them the fuck alone. A bit similar to giving your kids an ice cream so they shut up.

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10 hours ago, JALhazmat said:

Don’t Think it takes much breeze to get the small foils up and working properly and they certainly will have done a lot of work since then. .................... .................................................... ...................................

There has to be a sweet spot for that --- drag v takeoff lift. I"m guessing ETNZ started on the small side of that, and the others started on the large side. Back in the 1987 cup, Stars and stripe did the same with their keel wings.

Other teams started small and were working their way larger and S/S started really large and worked their way smaller. Turns out the S/S  approach got to the right size quicker.

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8 hours ago, alphafb552 said:

So, just caught up with this thread after a while:

ETNZ is:

- trying out AM's batwing

- experimenting with LR's dual helmsman set up

- getting back to code 0s, even using it together with the jib

 

Running out of ideas to actually make the boat faster?

It seemed weird to me that they came out on social media a few days ago saying that now the focus was on sailing & race practice... and then they go and trial a batwing, & code zero.  Both options are, I think, extremely unlikely to come out in races.  If it is just 'ticking the box' as NO and Slingers say, it seems really late to be doing that.  Not sure what's going on.  

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22 minutes ago, jaysper said:

Which begs the question as to why would ETNZ insiders (if this is where 62 knots came from) make mention of a speed that cannot be attained in the race course?

I suspect they were all given a number to tell their mates so they leave them the fuck alone. A bit similar to giving your kids an ice cream so they shut up.

Agreed.  ETNZ knows that top speed is irrelevant.  My guess is  that they're excited about their boat speed and reaching 62 knots just adds to that.  I can imagine one of the team members talking to someone and saying how happy they were with their boat speed and that they even hit 62 knots...  The 62 knots is then the easy thing for that person to pass on - and the rumor starts. 

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9 minutes ago, 1eyedkiwi said:

It seemed weird to me that they came out on social media a few days ago saying that now the focus was on sailing & race practice... and then they go and trial a batwing, & code zero.  Both options are, I think, extremely unlikely to come out in races.  If it is just 'ticking the box' as NO and Slingers say, it seems really late to be doing that.  Not sure what's going on.  

Confusion and subterfuge for the excitable Italians' sake...normal AC transmission has resumed.

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I disagree. The 62 knts is an important number. Even if it was reached during bear-away (which is likely) that number would have been noted and it would not have escaped the notice of everyone.

62 is considerably faster than 54 which I think is the fastest recorded during a race. For the foils to be capable of 62 is significant and implies that they can be capable of sitting comfortably in the mid 50's.

All will be revealed soon.

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9 minutes ago, Barnyb said:

I disagree. The 62 knts is an important number. Even if it was reached during bear-away (which is likely) that number would have been noted and it would not have escaped the notice of everyone.

62 is considerably faster than 54 which I think is the fastest recorded during a race. For the foils to be capable of 62 is significant and implies that they can be capable of sitting comfortably in the mid 50's.

All will be revealed soon.

It’s not the number I’m questioning but the manner in which the information has supposedly entered the public domain. If the number is true, then LRPP have bigger problems than they thought.

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The world sailing speed record is only a touch over 65.4 knots.

I seriously doubt any AC75 has cracked 55 knots, let alone 60.

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5 minutes ago, Paddywackery said:

It’s not the number I’m questioning but the manner in which the information has supposedly entered the public domain. If the number is true, then LRPP have bigger problems than they thought.

We have big problems even if it is much less than that!

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1 hour ago, Barnyb said:

I disagree. The 62 knts is an important number. Even if it was reached during bear-away (which is likely) that number would have been noted and it would not have escaped the notice of everyone.

62 is considerably faster than 54 which I think is the fastest recorded during a race. For the foils to be capable of 62 is significant and implies that they can be capable of sitting comfortably in the mid 50's.

All will be revealed soon.

I agree with your inference that ETNZ will be faster (I think by a lot) but disagree with the reasoning.

For me 62 knots is like selling a product at a loss of $100 per unit but making it up on volume.

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3 minutes ago, The Advocate said:

Have any of them tried to tow to a top speed or to find where the cavitation point is?

Doubt that any team has the capacity to tow at 50 knots plus, could be wrong though.

 

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4 minutes ago, The Advocate said:

Have any of them tried to tow to a top speed or to find where the cavitation point is?

It wouldn't surprise me to find out that there maybe a VNE in place.

They have electronic speed limiters, don't they?

I think maybe, Herbie provides a fix though - or was it Revo?

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5 hours ago, mauriciogfj said:

Proof.
America's Cup: Emirates Team New Zealand christen their first AC75

:):D:lol: good one mauri!                A lot has been said about Te Rehutais’ designers attempts to reduce aero and this photo would seem to support that but in reality her bow is a hell of a lot chunkier than LRPP. (Not really visible in this photo)  I’m not sure what her designers were thinking when adding that above w/line flare up forward? It would be interesting to see wind tunnel comparisons between the 2 boats.  

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Just now, he b gb said:

:):D:lol: good one mauri!                A lot has been said about Te Rehutais’ designers attempts to reduce aero and this photo would seem to support that but in reality her bow is a hell of a lot chunkier than LRPP. (Not really visible in this photo)  I’m not sure what her designers were thinking when adding that above w/line flare up forward? It would be interesting to see wind tunnel comparisons between the 2 boats.  

That one is Te Aihe not Te Rehutai

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Just now, he b gb said:

...  I’m not sure what her designers were thinking when adding that above w/line flare up forward?...

When the boat was rolled out, my conclusion was that that shape was intended to avoid heading for a pitch pole should the boat fall off the foils. In the early days of the AC75 of say 4 months ago, that might have seemed a sensible solution. However, since then we have seen that barring the occasional catastrophe, such nosedives do not happen that often, and when they do, they do not pose too many problems - LR has had a few in the last few weeks of racing - and continued merrily on her way without too much time loss.

As you said, would be interesting to know what the comparative aero performance is between LR and ETNZ

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My thoughts exactly, it may just be to fair the hull lines into the crew aero but looks draggy to me.

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20 hours ago, jaysper said:

Gotta be photoshopped. Everyone knows ETNZ can foil at 0 knots boat speed.

 

6 hours ago, mauriciogfj said:

Proof.
America's Cup: Emirates Team New Zealand christen their first AC75

If this is the speed, I feel much more relieved! :D

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1 hour ago, Sailbydate said:

The world sailing speed record is only a touch over 65.4 knots.

I seriously doubt any AC75 has cracked 55 knots, let alone 60.

Why? A French bloke on a kite has done 57 so why shouldn’t an aC75 be capable of 55? 

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Just now, JALhazmat said:

Why? A French bloke on a kite has done 57 so why shouldn’t an aC75 be capable of 55? 

Foil cavitation??  Was the kite surfer reliant on foils?

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11 minutes ago, JALhazmat said:

Why? A French bloke on a kite has done 57 so why shouldn’t an aC75 be capable of 55? 

 

Because there is no French bloke at the helm of any AC75 at the moment.

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43 minutes ago, alphafb552 said:

When the boat was rolled out, my conclusion was that that shape was intended to avoid heading for a pitch pole should the boat fall off the foils. In the early days of the AC75 of say 4 months ago, that might have seemed a sensible solution. However, since then we have seen that barring the occasional catastrophe, such nosedives do not happen that often, and when they do, they do not pose too many problems - LR has had a few in the last few weeks of racing - and continued merrily on her way without too much time loss.

As you said, would be interesting to know what the comparative aero performance is between LR and ETNZ

The hull aero is largely irrelevant.  We've seen proof of that when viewing the relative performances of each boat with widely varying hull shapes.  The key difference between AM+IN vs LR+ETNZ is main control.  The key is being able to fly as much sail as possible for a given wind velocity and being able to handle the variances in that velocity.  To do that they need control systems that allow the ability to depower when and as required.  When you crack that nut you can fly with smaller foils and therefore less drag.

Perhaps the biggest "trickle down" component of this AC will be the twin skin boom-less mains.  They are a damn sight safer and more efficient than what the average sailor has been used to.  

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1 hour ago, The Advocate said:

Have any of them tried to tow to a top speed or to find where the cavitation point is?

It wouldn't surprise me to find out that there maybe a VNE in place.

The power required to tow one of these up to over 50 knots would be well beyond the current chase boats I reckon.  They can only just get to those speeds without anything in tow...

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16 minutes ago, Kate short for Bob said:

Perhaps the biggest "trickle down" component of this AC will be the twin skin boom-less mains.  They are a damn sight safer and more efficient than what the average sailor has been used to.  

Only TR is actually boomless

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7 minutes ago, DickDastardly said:

The power required to tow one of these up to over 50 knots would be well beyond the current chase boats I reckon.  They can only just get to those speeds without anything in tow...

Am thinking the most power required would be used getting the boat onto the foils, but if the chase boats already top out around 50, then that settles that.

I imagine that is a suitable boat was brought in, it would have been noticed. A fun thought though having a full size tow model, very Bethwaite.

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46 minutes ago, strider470 said:

 

Because there is no French bloke at the helm of any AC75 at the moment.

Good answer, Strider! ;-)

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55 minutes ago, Kate short for Bob said:

The hull aero is largely irrelevant.  We've seen proof of that when viewing the relative performances of each boat with widely varying hull shapes.  The key difference between AM+IN vs LR+ETNZ is main control.  The key is being able to fly as much sail as possible for a given wind velocity and being able to handle the variances in that velocity.  To do that they need control systems that allow the ability to depower when and as required.  When you crack that nut you can fly with smaller foils and therefore less drag.

Perhaps the biggest "trickle down" component of this AC will be the twin skin boom-less mains.  They are a damn sight safer and more efficient than what the average sailor has been used to.  

I'm not so sure it's that simple.  At 35 plus knots I'm sure that drag is very, very important. Drag from, crew, sails, foils, hulls etc. It's almost as if ETNZ and LR care more about drag than power they generate from their rig.

 

 

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1 hour ago, DickDastardly said:

I just spat out my cornflakes

I didn't say it wasn't important.  However the point is that at the end of the day all of these boats have a pointy bit at the front and a square bit at the back.  The gains made from changing the hull shape are marginal compared to those that can be gained from sail management.

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4 minutes ago, Kate short for Bob said:

I didn't say it wasn't important.  However the point is that at the end of the day all of these boats have a pointy bit at the front and a square bit at the back.  The gains made from changing the hull shape are marginal compared to those that can be gained from sail management.

I think you need to look up the meaning of irrelevant.

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26 minutes ago, Clapham said:

I'm not so sure it's that simple.  At 35 plus knots I'm sure that drag is very, very important. Drag from, crew, sails, foils, hulls etc. It's almost as if ETNZ and LR care more about drag than power they generate from their rig.

Draw an analogy with a racing car.  If you have a car that has more power therefore higher speed and more gears than another car then who wins?

The marginal gains in terms of hull shape is minimal.  We have seen that so far in this AC.  The hull shape wasn't the cause of AM or Ineos's demise.  With AM it was their inability to depower (drop down a gear or three) when required and with INEOS an inability to power-up when needed.

So if more sail area equals power (more gears) then the ability to control that power (change gears) must have more marginal gains than hull shape. 

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6 minutes ago, jaysper said:

I think you need to look up the meaning of irrelevant.

It is irrelevant in terms of a boat.  Centuries of boating has proven that it is better to have a pointy bit at the front and a square bit at the back.  Although the square bit at the back is probably only relevant so you can have enough room for sailors to control the beast.

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7 minutes ago, Kate short for Bob said:

Draw an analogy with a racing car.  If you have a car that has more power therefore higher speed and more gears than another car then who wins?

The marginal gains in terms of hull shape is minimal.  We have seen that so far in this AC.  The hull shape wasn't the cause of AM or Ineos's demise.  With AM it was their inability to depower (drop down a gear or three) when required and with INEOS an inability to power-up when needed.

So if more sail area equals power (more gears) then the ability to control that power (change gears) must have more marginal gains than hull shape. 

I like the gullwing hull on ETNZ.

Wind flow under hull can create lift therefore meaning less foil area. I used to own a gullwing hull and trapping air beneath hull and water gave a soft ride.

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8 minutes ago, Kate short for Bob said:

It is irrelevant in terms of a boat.  Centuries of boating has proven that it is better to have a pointy bit at the front and a square bit at the back.  Although the square bit at the back is probably only relevant so you can have enough room for sailors to control the beast.

These boats have one purpose which is to make it faster than the opposition around the course.

At these speeds, aero of the hull has a significant impact on that so how can that not be relevant???

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8 minutes ago, Kate short for Bob said:

Draw an analogy with a racing car.  If you have a car that has more power therefore higher speed and more gears than another car then who wins?

The Mercedes F1 team expends a huge amount of effort to squeeze out every last scrap of drag reduction they can, as do the other teams.

Apparently they are not confident that more power alone will win races.

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