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9 minutes ago, Horn Rock said:

I was referring to when the original limits were set, way back yonks ago.

True, just strange to change them last week then be out with a set up using a sail that’s very much not a light air choice. 
 

 

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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

After many hours of consideration, a lot of in-depth research on the SA technical threads, extensive computational modelling and a few quick & dirty minutes in Photoshop, I have produced this anal

They towed out around 11am and the breeze was light and puffy to start with. Foiled down the Channel and headed out to the Bays. The breeze started to build around midday and they got some long runs i

Posted Images

7 hours ago, Lickindip said:

image.png.9d840c19bb07af895d170eef2b2dcd89.png

they tryed to put up a fake mainsail to cover up this doozy ... look at the gap on that thing

Rudder length can be set for each day, as long as measurer checks it. Long for chop, short for flat. 
https://docs.google.com/a/acofficials.org/viewer?a=v&pid=sites&srcid=YWNvZmZpY2lhbHMub3JnfGFjMzYtb2ZmaWNpYWwtbm90aWNlYm9hcmR8Z3g6ZGM0OGE0ZjZhNmFjOTQ1

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39 minutes ago, Mozzy Sails said:

Good idea, not hard to copy though

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2 minutes ago, JALhazmat said:

that's the one for what has just appeared on ETNZ.

 

there is one earlier that was for AM 

Thanks for that, good to know 

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The bat wing is not exactly a lucky charm. But it could be worse, it could be a bat wing with some green on top of it. :D I would put that thing back in the bat cave! :D

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11 hours ago, The_Alchemist said:

You need to spend some time hauling bodybags out to the refrigerator trucks in a hospital parking lot

It has been reported that in Indonesia, those found not wearing masks where appropriate are sentenced to digging graves for Covid victims and then burying the bodies.

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7 hours ago, JALhazmat said:

Which bit is hardly?

it wasn’t an AM idea?

they didn’t spend any money and it doesn’t work

Or no one had a word in anyone’s ear? ( will give you the last point as no one needed too as it was visible as soon as AM tried their version) 

it wasn’t an AM idea

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11 hours ago, Nutta said:

At some point the borders need to reopen. The vaccine mitigates effects of the virus, not stops transmission, nor eliminate the wee beastie.

When the borders do open, we need to be prepared to manage some level of infection, the significant illness that can result, and possibly deaths. 

There is sweet fuck all going on to prepare for that. Just a perception that the virus will solve it all and then things will return to normal.

 

I hate to keep going off topic, but the borders will open when people stop dying from an uncontrolled virus.  It is actually a very simple and well understood concept.  The problems continue when people want to open up when they see a drop in infections, but it is still out of control. 

Here is a chart that shows the effectiveness of vaccines on other diseases.  We do not have to live with a certain level of deaths and infections.  The virus dies when there are no hosts (we may have to ensure that it doesn't remain in some animals, etc...)

1054250400_ScreenShot2020-07-03at12_56_02PM.thumb.png.9762cd53d3514a007e4c8ef42b0accf7.png.bc2825c51a30c536a970ca9378e190bf.png

The Pfizer and Moderna vaccines are 95% effective.  We do not know for how long the immunity will last, maybe we will need an annual booster shot.  Here is another quick chart that shows herd immunity thresholds for vaccine preventable diseases:

1628244289_ScreenShot2020-07-03at12_52_13PM.png.cf82819f81c74e31a81fef58ed7c7f08.png.50e90f7defb4269f8c6ccbfd1cff9987.png

Covid-19 has a herd immunity in the 80% range.  That is in the smallpox range, a disease that has been "eliminated" from most countries (prior to the rise of the anti-vaxxers).  We may need annual booster shots for Covid-19, but who knows...  But we should be able to return to a mostly normal life within the next year or so (need worldwide vaccinations to take place before all barriers are removed).

Now back to sailing....

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2 hours ago, strider470 said:

The bat wing is not exactly a lucky charm. But it could be worse, it could be a bat wing with some green on top of it. :D I would put that thing back in the bat cave! :D

Or with bananas on board... Ineos... hello?

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8 hours ago, Salty Seacock said:

Half your population voted in a fucking madman that put the world on edge for four long years. Once the virus struck, the people refused to wear masks or limit social contact because it was, "an infringement of our God given rights". This was encouraged by the President. The USA has 1,000 deaths a day because too many of their people are a bunch of arrogant idiots! Your former President cancelled the US's contribution to the WHO for fucks sakes. 

Israel spends four times the USA on medical research and has come up with their own vaccines that they're giving freely to the world.

Save us all from your fucking sanctimonious bullshit. 

I am not being sanctimonious.  The investments were in spite of the fckg orange pumpkin who did his best to destroy things.  I was just pointing out that the Covid vaccines are being made available around the world.  The US did invest billions ($1.95 billion to Pfizer) to speed up the production of them before they were approved (July 2020).  They took the chance the human trials would be positive.

Oh, by the way, Israel is using the Pfizer vaccine and the Israel Ministry of Health gave approval based upon the US FDA approval.  And the US has returned to the WHO.

https://ijhpr.biomedcentral.com/articles/10.1186/s13584-021-00440-6

Hey, I agree with all of your characterizations of the those idiots.  It was a cult that many followed and hopefully it is fading in the rearview mirror.

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50 minutes ago, JALhazmat said:

go on... who implemented it first on an AC75?

 

The swedes implemented bikes on a boat first, yet it didn't work.

AM implemented a "Batwing" main but it hindered them more than it helped.

Its not about who uses it first, its about who gets it right first.

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8 hours ago, Priscilla said:

According to the Herald Te Rehutai has been reaching never seen before speeds.

America's Cup 2021: Team New Zealand appear to trial new 'batwing' mainsail design, mirroring that of American Magic 
https://www.nzherald.co.nz/sport/news/article.cfm?c_id=4&objectid=12421888

It make sense.  Terry said in one of the press conferences that in heavy winds, they get just as much power and less drag with he batwing.

I still remember Terry in an interview with Gary Jobson back on Jan 12th.  Gary asked Terry how fast Patriot can go, and Terry said that they would pass him on US Route 50 (near Annapolis the speed limit is 65 mph (56.5 knots)).

I have no doubt that NZ is building speed and getting very fast.  Hopefully for their sake, they haven't sacrificed too much stability or light wind capabilities.

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28 minutes ago, Forourselves said:

The swedes implemented bikes on a boat first, yet it didn't work.

AM implemented a "Batwing" main but it hindered them more than it helped.

Its not about who uses it first, its about who gets it right first.

hi Indio... :)

no what Indio batted away was that it had been seen on AM before it was just shown on ETNZ.

that is an absurd position to take.

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17 minutes ago, Forourselves said:

The swedes implemented bikes on a boat first, yet it didn't work.

AM implemented a "Batwing" main but it hindered them more than it helped.

Its not about who uses it first, its about who gets it right first.

So now you come around.  So how do you know it hindered AM more than helped?  The announcers were attributing all of the control problems to a sail they did not understand.  We all know now that the AM had problems with some of the foils and control on the rudder, not really related to the batwing.

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23 hours ago, kiwin said:

I can't imagine why a genius such as yourself is not employed by the Government instead of all those tedious scientists with medical qualifications and PhD's and decades of experience. After all what can a collection of people who have spent 30 years studying this exact subject offer that a semi literate sailing forum troll can't after a few minutes at a keyboard.

Depends WHICH scientists you listen to.  There are any number of equally qualified scientists that are not being listened to.  Why?  

Key advisors Professor Michael Baker, Professor Nick Wilson, Dr Matthew Boyd and Dr Osman Mansoor.  Google "Dr Matthew Boyd NZ" and then do the same for Mansoor who is an active member of the Green Party.  That's who is advising the Government.  It is driven by ideology not science. 

Boyd, M., Mansoor, O. D., Baker, M. G., & Wilson, N. (2018). Economic evaluation of border closure for a generic severe pandemic threat using New Zealand Treasury methods. Australian & New Zealand Journal of Public Health, 42(5), 444-446. doi: 10.1111/1753-6405.12818

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6 hours ago, strider470 said:

The bat wing is not exactly a lucky charm. But it could be worse, it could be a bat wing with some green on top of it. :D I would put that thing back in the bat cave! :D

It's from the covid-19 bats, so watch out during the upwind legs!:ph34r:

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2 hours ago, The_Alchemist said:

.......................The announcers were attributing all of the control problems to a sail they did not understand.  ................................

If only ETNZ had someone in their program who understood this sort of sailplan :)

I wonder....?

image.thumb.png.ff9876c3059b30898444fad536ef453f.png

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2 minutes ago, Indio said:

It's from the covid-19 bats, so watch out during the upwind legs!:ph34r:

Better if we ( or the Brits) will stay well ahead then ;)

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3 hours ago, JALhazmat said:

if you hate it stop bloody doing it...

 

anyway I want to hear how @Indio thinks that AM didn't implement the bat wing on their AC 75 before anyone else

It was politically sensitive given the trumpscum-promoted origin of covid-19 from the Wuhan bats, and of course the team principals in AM. I thought you all knew that..B)

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3 hours ago, The_Alchemist said:

So now you come around.  So how do you know it hindered AM more than helped?  The announcers were attributing all of the control problems to a sail they did not understand.  We all know now that the AM had problems with some of the foils and control on the rudder, not really related to the batwing.

Are you saying a guy who is president of North Sails, is a former America’s Cup competitor, and who has also skippered offshore campaigns, doesn’t know what he’s looking at?

Are you saying one of the top foiling and 49er sailors of this generation doesn’t know what he’s looking at? Really?

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40 minutes ago, Forourselves said:

Are you saying a guy who is president of North Sails, is a former America’s Cup competitor, and who has also skippered offshore campaigns, doesn’t know what he’s looking at?

Maybe he had a vested interest in not saying the AM mainsail looked a good idea (it was made by a rival sailmaker)?

Oops. No, he would be more likely to say it was a great idea. Then the three other teams would be buying new North mainsails, as ETNZ have now done!

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16 hours ago, The_Alchemist said:

Wow, if someone gave you a new shitter, you would complain that is smells too nice....  the US gave a billion $'s to each of the major vaccine producers to help them scale up the testing and production.  It takes time to scale up the vaccine and get is distributed to the people.   The US has started vaccinations and is not on a pace of 1.5 million/day.  I am 64 and in the last "Bernal population" category and most likely will not get vaccinated until maybe July.  You in NZ will be vaccinated way before us.  Our cases have dropped dramatically since the holiday gatherings, but we still have over 1,000/day dying from Covid.

You guys live in a bubble of normality that no one else in the world enjoys.  You have a few hiccups and use them as excuses to claim the sky is falling.  You need to spend some time hauling bodybags out to the refrigerator trucks in a hospital parking lot (because the morgue is full) to give your a dose of reality!

My comments are not just direct to you, but the chorus of posters that just do not understand.

Yeah - Kiwi here and we know we have had it pretty good.  While the current three day lock-down is a pain (lets hope its 3 days - the weather is great today!), it pales in comparison to what's happened in the US and UK.  The US is at about 16% vaccinated as of today however, where NZ has a total of 0 vaccinated - the first 30,000 doses arrived 2 days ago, and the first 100 border workers will get the first jab here this weekend.  General population wont start to get vaccinated until July. https://ourworldindata.org/covid-vaccinations

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3 minutes ago, SiC said:

The US is at about 16% vaccinated as of today however, where NZ has a total of 0 vaccinated - the first 30,000 doses arrived 2 days ago, and the first 100 border workers will get the first jab here this weekend.  General population wont start to get vaccinated until July. https://ourworldindata.org/covid-vaccinations

Don't forget to vaccinate the laundry staff washing the sheets of the layover aircrew on the private jets flying in with the billionaires!

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1 hour ago, Kate short for Bob said:

Depends WHICH scientists you listen to

And clearly, NZ has listened to the right scientists. I am in the UK at the moment. It's a fucking disaster. It's an economic disaster as well as an epidemiological disaster. NZ, unlike the UK is not going to suffer the worst recession since the 18th century, nor does it have 40% of it's frontline medical staff suffering from PTSD, nor is it having to build special facilities to cater for thousands suffering from "long Covid". NZ has done it right, and you, Bob or Kate or Dick or whatever your name is, are an insufferable cretin.

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53 minutes ago, winchfodder said:

Don't forget to vaccinate the laundry staff washing the sheets of the layover aircrew on the private jets flying in with the billionaires!

I thought the rich fucks and their servants just burned the dirty clothes and put on clean ones every day.  That's what I do anyway, no stinking laundry required.

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2 hours ago, Forourselves said:

Are you saying a guy who is president of North Sails, is a former America’s Cup competitor, and who has also skippered offshore campaigns, doesn’t know what he’s looking at?

Are you saying one of the top foiling and 49er sailors of this generation doesn’t know what he’s looking at? Really?

that commentary made me wince.

Firstly, it seemed like bad form from Ken, regardless of what he really thought. 

Secondly, yes, they seemed unstable using it in the semis... but it was also the strongest winds. I think one of the other commentators said they looked unstable with it in practice as well (Nathan?). But again, it's AM windy sail... so is it the sail that causing the instability, or just that when they use it it's 20 knots and the boat is doing 40-50? 

Perhaps the commentary team had inside info that it caused stability issues? If so they (commentators) didn't explicitly say that. 

I mean, it' hardly like we saw AM dead stable with a normal main in the same conditions. 

Who knows if ETNZ will use it, but I don't think we've seen enough based on AM to write it off as a concept. 

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3 minutes ago, Mozzy Sails said:

that commentary made we wince.

Firstly, it seemed like bad form from Ken, regardless. 

Secondly, yes, they seemed unstable using it in the semis... but it was also the strongest winds. I think one of the other said they looked unstable with it in practice as well. But again, it's their windy sail... is it the sail that causing the instability, or just that when they use it it's 20 knots and the boat is doing 40-50? 

Perhaps they had inside info that it caused stability issues? Is so they (commentators) didn't explicitly say that. 

I mean, it' hardly like we saw AM dead stable with a normal main in the same conditions. 

Who knows if ETNZ will use it, but I don't think we've seen enough based on AM to write it off as a concept. 

Agree, I wondered if ETNZ had it all along, only deciding now to bring it out to mess with heads. 

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2 minutes ago, southseasbill said:

Supposed to hear late this afternoon. The Health dept usually give an update at 1pm on any new cases detected. It's 11:47am here right now.

Nice one, thanks for the info Bill 

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Can you see the faint marks of where the logos (emirates fly better) used to be before the recut? 

Suggests they're just trialling AMs idea, but with a bit more radical with the further mainsail interpretation.

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7 minutes ago, Mozzy Sails said:

Can you see the faint marks of where the logos (emirates fly better) used to be before the recut? 

Suggests they're just trialling AMs idea, but with a bit more radical with the further mainsail interpretation.

Fair point

 

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6 hours ago, The_Alchemist said:

I hate to keep going off topic, but the borders will open when people stop dying from an uncontrolled virus.  It is actually a very simple and well understood concept.  The problems continue when people want to open up when they see a drop in infections, but it is still out of control. 

Here is a chart that shows the effectiveness of vaccines on other diseases.  We do not have to live with a certain level of deaths and infections.  The virus dies when there are no hosts (we may have to ensure that it doesn't remain in some animals, etc...)

1054250400_ScreenShot2020-07-03at12_56_02PM.thumb.png.9762cd53d3514a007e4c8ef42b0accf7.png.bc2825c51a30c536a970ca9378e190bf.png

The Pfizer and Moderna vaccines are 95% effective.  We do not know for how long the immunity will last, maybe we will need an annual booster shot.  Here is another quick chart that shows herd immunity thresholds for vaccine preventable diseases:

1628244289_ScreenShot2020-07-03at12_52_13PM.png.cf82819f81c74e31a81fef58ed7c7f08.png.50e90f7defb4269f8c6ccbfd1cff9987.png

Covid-19 has a herd immunity in the 80% range.  That is in the smallpox range, a disease that has been "eliminated" from most countries (prior to the rise of the anti-vaxxers).  We may need annual booster shots for Covid-19, but who knows...  But we should be able to return to a mostly normal life within the next year or so (need worldwide vaccinations to take place before all barriers are removed).

Now back to sailing....

A year? 

"Tell him he's dreaming".... 

I'm hearing five at the least. 

images (14).jpeg

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19 hours ago, Gissie said:

I am happy to agree we have lucked out. Some due to our leaders, but mainly due to our spread out style of living and lack of the unlicensed transport. An example is this last escape, meant to be much more virulent yet no other cases appearing at the moment. This lack of further cases has zero to do with our leaders. 

The reality is they have done okay. Yet the they have been put on a pedestal and treated as gods walking amongst us. Especially by the media who fawn all over Jacinta and Bloomfield. This blind adulation is a dangerous thing and could well end in tears. 

Anyway, back to the boats. 

But i bet if it got out of hand with hundreds or thousands of cases along with deaths, it would then be entirely the fault of our leaders?

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You've gotta hope nothing goes wrong with their runner pre-sets .

That's a couple of great points to get one hooked around .

Shit like that can take awhile to sort once they're snagged .

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2 hours ago, winchfodder said:

Maybe he had a vested interest in not saying the AM mainsail looked a good idea (it was made by a rival sailmaker)?

Oops. No, he would be more likely to say it was a great idea. Then the three other teams would be buying new North mainsails, as ETNZ have now done!

Or maybe he just knows what he’s talking about.

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4 minutes ago, Forourselves said:

Or maybe he just knows what he’s talking about.

I would like to agree but they way he said it lacked conviction and as Mozzy said, made me wince. He can’t help himself being smarmy every now and then.

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14 hours ago, Mozzy Sails said:

Much has been made of ETNZ inversion, yet they must see merit in reduced sail area aloft. Inversion might be a good idea with unwanted sail area, but second perhaps to just reducing sail area. 
I am looking forward to hear what Ken Read has to say about this after dissing AM batwing (quantum) sails. 

In a webinar some months ago, Burns Fallow (ETNZ's principal and North sail designer) made mention of there is merit in inverting the top of the mainsail in terms of righting moment, but it comes at very significant drag penalty.

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50 minutes ago, JJD said:

But i bet if it got out of hand with hundreds or thousands of cases along with deaths, it would then be entirely the fault of our leaders?

No necessarily, I have this ability to be open in my thinking, becoming a lost art it would seem.

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2 minutes ago, Barnyb said:

ETNZ Batwing & the modification that was missed

But, on a day when all eyes were on the new mainsail, did anybody notice the newly adjusted rudder post?

https://www.livesaildie.com/etnz-batwing-the-modification-that-was-missed/?fbclid=IwAR2hBE5hoaPq8-pE9CcdU0x2Pp_Sk-AJrqJ1ge6TE8WLTIuJnPnaxL8teNQ

Yes :-) Also discussed are relevent interpretations :-D

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15 hours ago, Mozzy Sails said:

Much has been made of ETNZ inversion, yet they must see merit in reduced sail area aloft. Inversion might be a good idea with unwanted sail area, but second perhaps to just reducing sail area. 
I am looking forward to hear what Ken Read has to say about this after dissing AM batwing (quantum) sails. 

Having tried a 7.2sqm sail on a moth, it'll be a rocket upwind, but barely functional off the breeze, even in 15+ knots. But ETNZ will find the balance point.

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7 hours ago, The_Alchemist said:

I am not being sanctimonious.  The investments were in spite of the fckg orange pumpkin who did his best to destroy things.  I was just pointing out that the Covid vaccines are being made available around the world.  The US did invest billions ($1.95 billion to Pfizer) to speed up the production of them before they were approved (July 2020).  They took the chance the human trials would be positive.

Oh, by the way, Israel is using the Pfizer vaccine and the Israel Ministry of Health gave approval based upon the US FDA approval.  And the US has returned to the WHO.

https://ijhpr.biomedcentral.com/articles/10.1186/s13584-021-00440-6

Hey, I agree with all of your characterizations of the those idiots.  It was a cult that many followed and hopefully it is fading in the rearview mirror.

We all hope so. America used to lead the world in politics and betterment contributions. The rise of the Right has everyone freaking the fuck out. 

The vaccine isn't free for countries to help themselves to. There is an ROI on the costs incurred in the development.

New Zealanders I talk to are exceptionally appreciative of our position and have their own opinions as to why we're so sheltered from the plague. 

One difference is that, our Government put rules in place and we agreed and complied with very very few exceptions. 

We are free.

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1 hour ago, Forourselves said:

Or maybe he just knows what he’s talking about.

Maybe from his racing and business career,  though I still think he missed the point in claiming that the reason for the AM capsize was the leeward running backstay holding the main up.

 

"I am looking forward to hear what Ken Read has to say about this after dissing AM batwing (quantum) sails."

Not invented here!

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20 hours ago, Nutta said:

At some point the borders need to reopen. The vaccine mitigates effects of the virus, not stops transmission, nor eliminate the wee beastie.

When the borders do open, we need to be prepared to manage some level of infection, the significant illness that can result, and possibly deaths. 

There is sweet fuck all going on to prepare for that. Just a perception that the virus will solve it all and then things will return to normal.

 

Basically most of what you said about the vaccine is bullshit. The vaccine will effectively stop transmission by siloing the remaining cases or at-risk people away from each other enough to curb it. It can also eliminate the virus too if it's effective.

And when there is enough vaccine uptake there doesn't need to any significant preparation for new infections any more than there is for the seasonal flu in terms of healthcare measures. As for wider measures like ongoing border caution of varying types - well that is well underway and will be fine-tuned ongoing.

How you could get so much so wrong in the space of one post is fairly impressive.

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38 minutes ago, Stingray~ said:

low speed steering problems? 
 

:) 

Nah, just practicing going slow enough to make the match look like a race...

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5 hours ago, Forourselves said:

Are you saying a guy who is president of North Sails, is a former America’s Cup competitor, and who has also skippered offshore campaigns, doesn’t know what he’s looking at?

Are you saying one of the top foiling and 49er sailors of this generation doesn’t know what he’s looking at? Really?

No, where did you make that up from?

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5 hours ago, Flags said:

If only ETNZ had someone in their program who understood this sort of sailplan :)

I wonder....?

image.thumb.png.ff9876c3059b30898444fad536ef453f.png

I was a little surprised someone in AM beat GA to the punch on this. Reduced drag, more RM worked well for the foiling (and non foiling) A Cat, why not and AC75. Sails look much nicer than the fat heads IMHO

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3 minutes ago, NZL3481 said:

Provided the engineering for the rudder is up to it...

I doubt any design team would have difficulties  to copy this specific part

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Just now, strider470 said:

I doubt any design team would have difficulties  to copy this specific part

I'ts a task certainly easier if the rudders are steel. There are some engineering considerations if they're composite.

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Just now, NZL3481 said:

I'ts a task certainly easier if the rudders are steel. There are some engineering considerations if they're composite.

Of course. I'm not saying it's easy in general.

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3 hours ago, NZL3481 said:

In a webinar some months ago, Burns Fallow (ETNZ's principal and North sail designer) made mention of there is merit in inverting the top of the mainsail in terms of righting moment, but it comes at very significant drag penalty.

Ever since all the discussion of inversion, I've been looking at sail upper sections during races but haven't seen any sign of it.  Not that we get much in the way of suitable overhead shots though.

Has anyone actually spotted inversion during a race?

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6 minutes ago, MaxHugen said:

Ever since all the discussion of inversion, I've been looking at sail upper sections during races but haven't seen any sign of it.  Not that we get much in the way of suitable overhead shots though.

Has anyone actually spotted inversion during a race?

Ever since first mooted in SF there has been very little evidence. However, Nathan O has said it’s an important factor for the F50s, so it is used even if difficult to see. 

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4 minutes ago, RobG said:

Ever since first mooted in SF there has been very little evidence. However, Nathan O has said it’s an important factor for the F50s, so it is used even if difficult to see. 

I think it's more practical with the F50's wing sail, since it's shape is not determined by air pressure. 

I check out the top draft stripe of the AC75 main, as it's not that far from the sail head, for any sign of being at least flat (no camber).  I think it would have to be if the top is inverted.  No visible sign of that even in the strongest winds we've seen in races.

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50 minutes ago, MaxHugen said:

Ever since all the discussion of inversion, I've been looking at sail upper sections during races but haven't seen any sign of it.  Not that we get much in the way of suitable overhead shots though.

Has anyone actually spotted inversion during a race?

Skiff sailors have used mainsail inversion to increase RM for over 20 years, especially when power reaching with the asy flying.

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2 hours ago, The_Alchemist said:

No, where did you make that up from?

You said the commentators based their assertions on "a sail they didn't understand"

One would think they both understand exactly what they're looking at, how it works, and the pro's and cons of that sail.

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2 minutes ago, Don said:

Skiff sailors have used mainsail inversion to increase RM for over 20 years, especially when power reaching with the asy flying.

Yes, I've seen the pic that Mikko posted of the Finns. That was done by a lot of mast bend, laterally I believe.  Way beyond what the AC75 mast can achieve.

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4 hours ago, Don said:

Skiff sailors have used mainsail inversion to increase RM for over 20 years, especially when power reaching with the asy flying.

True, and something I am aware of myself. When the top batten pop inverted it's much nicer... until it pops back again. It's very hard to control.

With the control lines they have up at the top, they can 'hold inversion' in place better. Which would be nice, if not anything more than stopping flogging.

However, classes with multiple rig sizes (18s) still downsize when the breeze is up. 

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I'm still suprised they are not using snub tailed aero helmets like the kask bambino et-al, especially the grinders.  There are significant aero gains to be had.  

 

https://www.evocycles.co.nz/Product/308179/kask-bambino-pro-aero-helmet?variationId=308182&gclid=CjwKCAiAmrOBBhA0EiwArn3mfI5YfVWlpxXviHKZ-TrVA6dHq07RXDBHjSrOS9OXArdMt8kYONq1KRoCWl4QAvD_BwE

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