America’s Cup 37

Slingsby says the flight controls aren’t working well enough, but cos of design decisions taken months ago, they can’t be changed.

I agree that the recumbent cyclors just don’t look as efficient…they did seem to run out of hydraulic power in one of the round robin races (allegedly)

Well done INEOS! Sf2 is looking tense, especially after the traveller broke today on LRPP

So day one of the LV Cup finals was interesting!

Race 1 in max wind conditions and Ineos looked a handful and comfortably beaten – Race 2 in the same conditions and all of a sudden Ineos looks much more manageable and takes the win.

Rumour has it they have a live data feed back to Mercedes F1 in Brackley who analyse the data and then give feedback re the foils. Bonkers!

Hopefully it’s going to be a good series regardless of the winner.

I was reading they might have adjusted  where & how the hydraulic  pressure was used. More biased to sail trim rather than foil trim. Apparently (and I know nothing about sailing a foiling boat) fine control of foiling height is better controlled via loading the foils from sail pressure.

Did seem from the 2 races that the 2 teams are evenly matched, hopefully that will also be the case in the lighter winds forecast for Saturday.

Amazing, amazing, AMAZING!!!

[lots of hand clappy emoji’s]

Really enjoyed that, especially The Inside Track Analysis Show on the Ineos Britannia YouTube channel.  For a layman like me it put a lot more colour into the racing.

🙂

Yes, I only understand about 5% of what they talk about but it’s pretty impressive tech.

Yeah fantastic win.  Bring on NZ!

(Saw that NZ have been training against Alinghi and Alinghi managed to capsize…oops).

Really enjoyed that, especially The Inside T(r)ack Analysis Show on the Ineos Britannia YouTube channel.  For a layman like me it put a lot more colour into the racing.

As I said, layman!

So, ineos beat luna rosa. An epic final series with the italians more fragile but quicker. Ineos more reliable and able to grind out the wins.  First tine since i was a dot that a uk boat has made the final. Now how do we stack up against the kiwis?

That is going to be the interesting thing, all will be answered on Sat I suspect. I’m disappointed the Swiss have been warming up the Kiwis..

I thought that wasn’t allowed (racing outside of competition)?

The competition has been fantastic so far – the inaugural women’s AC starts tomorrow with Hannah Mills skippering for GB.

Now how do we stack up against the kiwis?

They look fast and consistent….

An epic final series with the italians more fragile but quicker.

There’s no data that says that Luna Rossa was faster.

If anything Ineos had consistently slightly better VMG and seemed better through the manoeuvres.

23 minutes and we find out what the delta is.

Not if there’s no wind!

I know less than nothing about sailing, I can’t fathom how you can turn a boat and sail back the way you came? I mean if the wind blows one way surely that’s the only way you go? How can you then turn and sail into it? Anyway…….I have to say despite not understanding the first thing about, the rules, tactics or how you win, I have been weirdly sucked in to watching it and finding myself enjoying it.

I can’t fathom how you can turn a boat and sail back the way you came?

its a bit like how you can get a bike up a slope thats a bit too steep – you zig zag your way up. Its inefficient, but you get there in the end.

I can’t fathom how you can turn a boat and sail back the way you came? I mean if the wind blows one way surely that’s the only way you go?

Think about an aircraft wing. It creates lift at 90 degrees to the airflow by creating a higher pressure on the bottom surface than on the top, this causes airflow to be deflected downwards, creating enough lift to keep the aircraft flying. A yacht can sail crosswind by deflecting the airflow sideways. Conservation of momentum means that the airflow deflection creates thrust in the opposite direction to the airflow so yachts can create thrust at 90 degrees to the wind direction, and they can sail crosswind much faster than the windspeed. Because they have a keel or centerboard to stop them from just skidding across the surface of the water, that thrust can be used to sail upwind.

Race 1 summary. Light airs. Poor start by ineos who were delayed by a battery change. NZ quicker upwind than Ineos and covered well. Game over after first beat. Ineos faster downwind but not enough to make up for upwind losses. Not a massive loss but not what you’d call tight. NZ to win in 9.

Oh dear. Second race a little closer but…

7-0 a possibility

NZ will probably win

But it’s too early to right off Ineos.

There were 2 related problems today

Shifts and variation in wind speed meant it really mattered where you are on the course and being in phase with the shifts

Once you are ahead or just level pegging and in phase or on the correct side then you’re going to win

I know less than nothing about sailing, I can’t fathom how you can turn a boat and sail back the way you came?

It’s worse than you think. It’s voodoo in both directions. They sail away from the wind faster than the wind. So they aren’t blown along in either direction. They are so fast they can see wind ahead on the water and catch up with it

Sort of answering Andy4d:
Sailing progressed slowly for thousands of years. Stick a big keel on a boat to stop it getting blown downwind, make an aerodynamic sail that can generate forward force and hey presto, you can sail back and forth at right angles to the wind.
Some refinement and you can head upwind (where the wind is blowing from) at the expense of speed.
A bit more experimentation and you find different combinations get more speed, more upwind.
Then people found that if there was a way to get the big draggy hull up out of the water you could sail much faster, and go upwind more. Windsurfers really popularised this. As a windsurfer myself since the mid 1980s I’ve witnessed massive and rapid change. We can go faster than the wind, at 90 degrees to it. In fact there have been times in strong winds that I’ve gone a long way upwind, really bloody fast (maybe 20 degrees upwind, which is nothing compared to a yacht with a keel, but I’ve just got a 40cm fin at the very back) because its the only way to slow down.
We go that fast because we’re planing, all but 10% of the board is out of the water so most of the drag is gone. And water is very draggy. Speedboats have massive engines and do about 10 mpg to belt along at 30mph. (25 knots – think of a knot as mph plus vat, (not quite, but near enough).
Then someone thought “why don’t I put a hydrofoil on the bottom of my fin?”. So now we have little aeroplanes stuck to the end of a one metre fin (now confusingly called a mast) which raise the whole kit and caboodle up clear of the water, eliminating nearly all the drag and they whiz along in really low wind, and get upwind like you wouldn’t believe.
So now you don’t even need a mast and sail, just an inflatable wing that you can hold in one hand, and a board the size of an ironing board. About £1,500 will get you as much fun on the water you can have with your wetsuit on.
But on the other hand spend another hundred million or so and you can adapt the same principles to a catamaran and get to compete in the Americas Cup. With the added bonus of seasickness.

Rumour has it they have a live data feed back to Mercedes F1 in Brackley who analyse the data and then give feedback re the foils. Bonkers!

It’s not a rumour, they have live data feed to and from Mercedes HQ, so they get actual analysis on the fly, which is borderline voodoo, from a competition sailing pov!

they have live data feed to and from Mercedes HQ, so they get actual analysis on the fly,

Does the driver have a public whinge on radio about strategy and how he knew all along it was wrong and the team are to blame for ****ing it up for him?

Re shifts and wind speed changes over the course; in light to moderate conditions there is a significant increase in AC75 boat speed for a small increase in true windspeed. As a result, sailing into the gusts, both upwind and down, is gaining significantly and almost certainly more than using the shifts. On a related note, it takes ineos longer to get back up to speed after a tack than NZ which really isn’t helping tactics. I think mozzy did a video that mentioned this a week or so ago.

As @ampthill said earlier – the lead boat has a significant advantage in picking what wind to sail in and in dumping dirty air all over the following boat. It’s tough being second in these races.

I liked how a commentator called it a design competition that ended with a race. I guess that how a lot of these elite races (F1 etc) are these days.

I liked how a commentator called it a design competition that ended with a race.

Any technology driven sport is the same. The designers and team managers have to juggle numerous variables and try to find the best overall compromise. The best thing for the sport is when you get very changeable conditions and different teams are faster in different conditions.

It’s not a rumour, they have live data feed to and from Mercedes HQ

I could be wrong but I don’t think the data feed from HQ is live to the boat….certainly the chase boats aren’t allowed to communicate with the AC75 during a race, so is be surprised if HQ were.

No coms’ to the boat during the race, not even audio

An ex student of mine was interviewed in a video dock side . He’s on the data team. I think his team is looking at the data from a sailing point of view. He said they package the data for the coaching team

There’s a good video in boat prep. They start at 5 in the morning with one guy scanning the structure. They tend to do software updates after the race to reduce the risk of mucking things up

A big thing this year is linked controls. So there might have a preset to bear away. As you adjust the sail angle it’ll auto adjust the sail depth. In wonder if that’s what they are doing in Brackley

As I understand it, the way the F1 teams use the data is they run test programs during practice then upload that data to HQ overnight and run simulations to find the optimum setup. In that case, they need to decide on a suitable compromise between one-lap pace for qualifying and race pace, especially when following other cars. I assume AC will be similar, analyzing the data to try to optimize the boat for the expected conditions and also to respond to any strengths or weaknesses of the other boat.

I like how they’ve copied the ‘race is determined at the start but you struggle on watching in case the leader makes a catasrophic error which almost never happens because they are very good’ part of F1 too

Looking like it’s going to be a bit of a walkover. Maybe if the wind picks up it might change things but at the moment, as a competition, it’s a non-event.

NZ faster and tactically better. Game over. 7-0. F1 analogy is good.

Once we had the penalty it was game over. But on the water it seemed like the performance differential was in NZs favour. More so than races 1 and 2

The big hull must pay a penalty on the tacks. Your heading into a strong wind unpowered.

Maybe like F1 they should be made to use 2 different sails during the race

Maybe like F1 they should be made to use 2 different sails during the race

Back in the AC75 cat days they did use an asymmetric / code zero for the downwind leg. But with them going faster than the wind it didn’t work as effectively as it does on a displacement boat so they dropped it pretty quickly.  Basically the jib is now just there to do it’s job of pushing air over the main quicker.

Sadly Kiwi boat just looks too fast. IB won the start today but couldn’t keep a lead. Zero mistakes from the kiwis.

sadly a competition where the holder gets to set the racing rules and technological class rules for the boat to their advantage just seems a bit pointless. Roll on sail GP.

Disregarding penalties, starts etc, the Kiwi boat just has more boatspeed on all points.

I hope it blows tomorrow…